Ismail A Shafik

Summary

Affiliation: Cairo University
Country: Egypt

Publications

  1. ncbi request reprint The effect of external urethral sphincter contraction on the cavernosus muscles and its role in the sexual act
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Urol Nephrol 39:541-6. 2007
  2. ncbi request reprint Effect of straining on the muscles of the anterior abdominal wall. Identification of the 'straining-abdominal wall reflex'
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 11:2174-8. 2006
  3. ncbi request reprint Electromyographic study of the anterolateral abdominal wall muscles during ejaculation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    J Sex Med 4:1022-7. 2007
  4. ncbi request reprint Study of interstitial cells in the penis: human study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Sex Med 4:66-71. 2007
  5. ncbi request reprint Surgical anatomy of the perineal muscles and their role in perineal disorders
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Anat Sci Int 80:167-71. 2005
  6. doi request reprint The anterolateral abdominal wall muscles during vesical filling and evacuation: electromyographic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo, Egypt
    Urology 71:621-4. 2008
  7. pmc The hypoactive corpora cavernosa with degenerative erectile dysfunction: a new syndrome
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Urol 6:13. 2006
  8. ncbi request reprint Does the composition of voided urine reflect that of the renal pelvis?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, 11121, Egypt
    Urol Res 34:261-4. 2006
  9. ncbi request reprint The cavernoso-anal reflex: response of the anal sphincters to cavernosus muscles' stimulation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Asian J Androl 8:331-6. 2006
  10. ncbi request reprint Sperm DNA fragmentation
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:197-208. 2006

Detail Information

Publications148 found, 100 shown here

  1. ncbi request reprint The effect of external urethral sphincter contraction on the cavernosus muscles and its role in the sexual act
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Urol Nephrol 39:541-6. 2007
    ..We investigated the hypothesis that external urethral sphincter contraction induces cavernosus muscles' contraction...
  2. ncbi request reprint Effect of straining on the muscles of the anterior abdominal wall. Identification of the 'straining-abdominal wall reflex'
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 11:2174-8. 2006
    ..These findings suggest presence of a 'straining-abdominal wall reflex'...
  3. ncbi request reprint Electromyographic study of the anterolateral abdominal wall muscles during ejaculation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    J Sex Med 4:1022-7. 2007
    ..The anterolateral abdominal wall muscles (AAWMs) are composed of the external and internal oblique, transversus abdominis, and the rectus abdominis muscles...
  4. ncbi request reprint Study of interstitial cells in the penis: human study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Sex Med 4:66-71. 2007
    ..Specialized pacemaker cells, similar to the interstitial cells of Cajal (ICC) of the gut, have been detected in the urinary organs and are thought to pace their motile activity...
  5. ncbi request reprint Surgical anatomy of the perineal muscles and their role in perineal disorders
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Anat Sci Int 80:167-71. 2005
    ..Further studies to investigate the role of the perineal muscles in the functional disorders of the perineum are needed...
  6. doi request reprint The anterolateral abdominal wall muscles during vesical filling and evacuation: electromyographic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo, Egypt
    Urology 71:621-4. 2008
    ..We investigated the hypothesis that the AAWM exhibit increased electromyographic (EMG) activity on vesical distension and contraction that presumably assists in vesical evacuation...
  7. pmc The hypoactive corpora cavernosa with degenerative erectile dysfunction: a new syndrome
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Urol 6:13. 2006
    ..The electro-cavernosograms of these patients recorded a diminished activity. We investigated the hypothesis that diminished corpus cavernosum electromyography activity was the cause of erectile dysfunction in these patients...
  8. ncbi request reprint Does the composition of voided urine reflect that of the renal pelvis?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, 11121, Egypt
    Urol Res 34:261-4. 2006
    ..The composition of voided urine does not seem to compare to renal pelvic urine. This concept needs to be considered in urine analysis evaluation and its relation to renal function...
  9. ncbi request reprint The cavernoso-anal reflex: response of the anal sphincters to cavernosus muscles' stimulation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Asian J Androl 8:331-6. 2006
    ..To prove the hypothesis that cavernosus muscles' contraction during coitus affects the reflex contraction of anal sphincters...
  10. ncbi request reprint Sperm DNA fragmentation
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:197-208. 2006
    ..Further research is needed to define the optimal test of sperm chromatin structure. The clinical application of this test will evolve as well...
  11. ncbi request reprint Demonstration of a physiologic sphincter at duodeno-jejunal junction
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 11:2790-4. 2006
    ..6+/-0.04 cm length was detected at the duodeno-jejunal junction. Together, the findings show that a high pressure zone exists at the duodeno-jejunal junction suggesting that this region might act as a physiological sphincter...
  12. ncbi request reprint Detection of predefecatory rectosigmoid wave activity for prevention of fecal soiling in infants
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 11:3096-9. 2006
    ..3+/-7.3 seconds, showed a significant increase in wave parameters and sounded the alarm. The findings show a method for early detection of defecation that can be used clinically to prevent fecal soiling in infants...
  13. ncbi request reprint Identification of the location of the colonic pacemakers: a histologic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    Front Biosci 10:1661-5. 2005
    ..In the rest of the colon, a chain of ICCs extended in the colonic wall in a linear fashion forming the 'pacemaker bundles' (PMBs). We postulate that the colonic electric waves start at the PMNs and spread in the colon along the PMBs...
  14. ncbi request reprint Interstitial cells of Cajal in erectile dysfunction
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:255-62. 2006
    ..ICC distribution was different in the various types of ED. It is suggested that this distribution interferes with SW discharge and the control of SMC activity with a resulting ED...
  15. ncbi request reprint Molecular andrology as related to sperm DNA fragmentation/sperm chromatin biotechnology
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:299-310. 2006
    ..Thus, these techniques are recommended for basic research rather than for routine andrology laboratories...
  16. ncbi request reprint Cavernosus muscle contraction during erection: is it voluntary or reflex, given the striated nature of the muscles?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Androl 27:695-9. 2006
    ..Cavernosus muscle contraction on corporal pressure elevation seems to be reflex and mediated through the corporo-cavernosal reflex (CCR). Changes in the evoked response amplitude would indicate a defect in the reflex pathway...
  17. ncbi request reprint Interstitial cells of cajal in patients with constipation due to total colonic inertia
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Invest Surg 19:147-53. 2006
    ..Further studies are needed to investigate the cause of Cajal-cell absence...
  18. ncbi request reprint Contractile activity of the prostate at ejaculation: an electrophysiologic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University Faculty of Medicine, Cairo, Egypt
    Urology 67:793-6. 2006
    ..Although it has been mentioned that the prostate contracts at ejaculation, a report of this finding could not be traced in published studies...
  19. ncbi request reprint Role of tunica albuginea in erection: is it a dynamic or a static role?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:81-6. 2006
    ..3 cmH2O, respectively. There was no significant difference between covered and non-covered corpora or between test and control animals. In conclusion, the TA seems to act as a cover to the corporal tissue. Its absence did not change ICP...
  20. ncbi request reprint The effect of esophageal and gastric distension on the crural diaphragm
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Surg 30:199-204. 2006
    ..We investigated the hypothesis that the crural diaphragm shares in the barrier function not only mechanically but also actively through a crural-esophageal-gastric reflex action...
  21. ncbi request reprint Urethral sphincters response to cavernosus muscles stimulation with identification of cavernoso-urethral reflex
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 51:335-43. 2005
    ..The cavernoso-urethral reflex can act a diagnostic tool in the investigations of patients with ejaculatory disorders...
  22. ncbi request reprint Electric activity of the testicular tunica albuginea during ejaculation: a canine study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Exp Biol Med (Maywood) 230:569-72. 2005
    ..The effect of pathologic conditions of the TA on ejaculation needs to be studied...
  23. ncbi request reprint Specialized pacemaking cells in the human Fallopian tube
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo, Egypt
    Mol Hum Reprod 11:503-5. 2005
    ..These cells may be responsible for initiating the slow waves (SWs) recorded from the SMC of the FT. This is a preliminary study, and further studies are needed to investigate the functional role of these cells...
  24. ncbi request reprint Effect of warming on the rectal motile activity: identification of rectal warming reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Surg Res 130:34-7. 2006
    ..Therefore, we investigated the hypothesis that rectal warming effects rectal dilation, which seems to indicate the existence of warm receptors...
  25. ncbi request reprint Oviductal motile response to penile cervical buffeting
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Gynecol Obstet 273:216-20. 2006
    ..We investigated the hypothesis that the oviduct exhibits increased motile activity during cervical buffeting...
  26. ncbi request reprint Conjoint corpora cavernosa and its role in erection
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 51:425-30. 2005
    ..However, further studies involving large number of cases are needed...
  27. ncbi request reprint Tunica albuginea overlapping: a novel technique for the treatment of erectile dysfunction
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Andrologia 37:180-4. 2005
    ..Microscopic examination of TA biopsies showed atrophy of the collagen fibres. Tunical overlapping aims at correction of TA flabbiness, corporal tissue support and improving of veno-occlusive mechanism...
  28. ncbi request reprint Changes in the urine composition during its passage through the ureter. A concept of urothelial function
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Urol Res 33:426-8. 2005
    ..These findings presumably indicate that the ureteral urothelium is a functioning epithelium and that the renal pelvic and ureteric urine are not identical...
  29. ncbi request reprint Effect of topical esophageal acidification on salivary secretion: identification of the mechanism of action
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo
    J Gastroenterol Hepatol 20:1935-9. 2005
    ..In the current study, the hypothesis that the salivary glands' response to esophageal acidification is a reflex was investigated...
  30. ncbi request reprint Histologic study of the tunica albuginea of the penis and mode of cavernosus muscles' insertion in it
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 52:1-8. 2006
    ..Considering the type of cavernosus muscles insertion into the TA, it appears that the fibrous belt exerts more CC compression than the other 2 types of insertion...
  31. ncbi request reprint Effect of external anal sphincter contraction on the ischiocavernosus muscle and its suggested role in the sexual act
    Ahmed Shafik
    2 Talaat Harb St, Cairo 11121, Egypt
    J Androl 27:40-4. 2006
    ..The reflex may prove of diagnostic significance in sexual function disorders, a point that needs further study...
  32. ncbi request reprint Study of the role of the transverse perineal muscles during rectal filling
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, 11121, Egypt
    Int J Colorectal Dis 21:698-704. 2006
    ..The function of perineal muscles at defecation is poorly addressed in the literature. We investigated the hypothesis that rectal distension effects reflex contraction of four perineal muscles...
  33. ncbi request reprint Role of the rectosigmoidal junction in fecal continence: concept of the primary continent mechanism
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Arch Surg 141:23-6. 2006
    ..We investigated the hypothesis that a continent mechanism seems to exist at the rectosigmoidal junction (RSJ), preventing the direct passage of stools from the descending colon to the rectum...
  34. ncbi request reprint Uterine effect of cervical buffeting: role of the cervicouterine reflex in coitus
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Reprod Med 50:837-43. 2005
    ..To investigate the hypothesis that cervical buffeting during coitus effects reflex relaxation and dilatation of the corpus uteri (CorU) smooth muscle; that mechanism acts to suck the ejected semen into the CorU...
  35. ncbi request reprint Electro-orchidogram: a non-invasive diagnostic tool in testicular pathologies
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Med Sci Monit 12:MT51-5. 2006
    ..We investigated the hypothesis that the transcutaneous electro-orchidogram (EOG) can act as a diagnostic tool in testicular pathological conditions...
  36. pmc Effect of micturition on the external anal sphincter: identification of the urethro-anal reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Spinal Cord Med 28:421-5. 2005
    ..We investigated the hypothesis that urine passage through the urethra effects EAS contraction to guard against possible flatus or stool leakage during micturition...
  37. ncbi request reprint A novel concept for the surgical anatomy of the perineal body
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Dis Colon Rectum 50:2120-5. 2007
    ..We investigated the hypothesis that perineal body is the site across which perineal muscles pass uninterrupted from one side to the other...
  38. ncbi request reprint Duodeno-jejunal junction: a histoanatomical study with the concept of the existence of an "anatomical" sphincter
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Surg Radiol Anat 29:661-5. 2007
    ..Duodenojejunal junction (DJJ) pressure decreased on duodenal contraction and increased on jejunal contraction. These findings postulated potential existence of anatomical sphincter at DJJ...
  39. ncbi request reprint Physiological considerations of the morphologic changes of the testicles during erection and ejaculation: a canine study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Urol Int 79:262-6. 2007
    ..We investigated the hypothesis that testicles and scrotal skin undergo morphologic changes that would serve the mechanism of erection and ejaculation...
  40. ncbi request reprint Electromyographic lag time and opening time: two novel noninvasive methods to investigate patients with anal outlet obstruction and their response to treatment
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Invest Surg 20:307-11. 2007
    ..They exhibited significant increase in anal outlet obstruction patients over the healthy volunteers. There was no significant difference between pelvic floor electromyographic lag time and opening time readings...
  41. ncbi request reprint Effect of urethral stimulation on vesical contractile activity
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Am J Med Sci 334:240-3. 2007
    ..We investigated the hypothesis that urethral stimulation effects vesical contraction...
  42. ncbi request reprint The electromyographic activity of the external and internal urethral sphincters and urinary bladder on vaginal distension and its role in preventing vaginal soiling with urine during sexual intercourse
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Gynecol Obstet 277:213-7. 2008
    ..We investigated the hypothesis that external (EUS) and internal (IUS) urethral sphincters and urinary bladder (UB) respond to penile thrusting (PT) of vagina in a way that prevents urinary leakage during coitus...
  43. doi request reprint A study of the effect of straining on the cavernosus muscles: identification of 'straining-cavernosus reflex' and its clinical significance
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Andrologia 40:23-8. 2008
    ..Meanwhile, the elevated intravaginal pressure presumably supports the rectovaginal septum against the concomitant high intrarectal pressure...
  44. ncbi request reprint Study of the effect of ileal distension on the motor activity of the jejunum, and of jejunal distension on the motor activity of the ileum
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    Hepatogastroenterology 54:2007-10. 2007
    ..We investigated the hypothesis that distension of either ileum or jejunum would affect the motile activity of the other...
  45. pmc Study of the response of the penile corporal tissue and cavernosus muscles to micturition
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Urol 8:4. 2008
    ..We investigated the hypothesis that the passage of urine through the urethra stimulates the corporal tissue and cavernosus muscles...
  46. ncbi request reprint Vaginal response to clitoral stimulation: identification of the clitorovaginal reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Reprod Med 53:111-6. 2008
    ..To investigate the hypothesis that glans clitoris (GC) penile buffeting effects contraction of the vaginal musculature and seems to increase arousal of the penis during coitus...
  47. pmc Effect of thermal cutaneous stimulation on the gastric motor activity: study of the mechanism of action
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo 11121, Egypt
    World J Gastroenterol 14:2226-9. 2008
    ..To investigate the mechanism of action of thermal cutaneous stimulation on the gastric motor inhibition...
  48. pmc Percutaneous perineal electrostimulation induces erection: clinical significance in patients with spinal cord injury and erectile dysfunction
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Spinal Cord Med 31:40-3. 2008
    ..We investigated the hypothesis that percutaneous perineal stimulation evokes erection in patients with neurogenic erectile dysfunction...
  49. doi request reprint An electrophysiologic study of female ejaculation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo, Egypt
    J Sex Marital Ther 35:337-46. 2009
    ..At orgasm, the electromyography of ischio-and bulbo-cavernosus muscles increased intermittently. The female orgasm was not associated with the appearance of fluid coming out of the vagina or urethra...
  50. ncbi request reprint The effect of gastric overfilling on the pharyngo-esophageal and lower esophageal sphincter: a possible factor in restricting food intake
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Med Sci Monit 13:BR220-4. 2007
    ..The authors hypothesized that gastric overdistension effects an increase in pharyngo-esophageal and lower esophageal sphincter activity aimed at inhibiting ingestion...
  51. pmc On the pathogenesis of penile venous leakage: role of the tunica albuginea
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Urol 7:14. 2007
    ..We investigated hypothesis that tunica albuginea atrophy with a resulting subluxation and redundancy effects venous leakage during erection...
  52. ncbi request reprint Identification of a vaginal pacemaker: An immunohistochemical and morphometric study
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Obstet Gynaecol 27:485-8. 2007
    ..Studies have shown that the greatest collection of ICCs occurred in the upper part of the posterior vaginal wall. The vaginal electric waves are suggested to originate from this 'centre' and spread caudally...
  53. ncbi request reprint Functional activity of the rectum: A conduit organ or a storage organ or both?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Gastroenterol 12:4549-52. 2006
    ..To investigate whether the degree of rectal distension could define the rectum functions as a conduit or reservoir...
  54. ncbi request reprint The "opening time" and "pelvic floor electromyographic lag time": two novel tools in the assessment of the anorectal evacuation time
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Invest Surg 19:307-11. 2006
    ..As there is no significant difference between opening time and pelvic floor muscles electromyographic lag time, it appears easier to apply the latter as it is simple, objective, and noninvasive...
  55. ncbi request reprint Study of the cremasteric muscle during erection
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 11121 Cairo, Egypt
    Surg Radiol Anat 28:569-72. 2006
    ..Mechanism of testicular elevation during erection is not known. We investigated the hypothesis that erection evokes reflex cremasteric muscle (CM) contraction which effects testicular elevation...
  56. ncbi request reprint Physioanatomical relationship of the external anal sphincter to the bulbocavernosus muscle in the female
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Urogynecol J Pelvic Floor Dysfunct 18:851-6. 2007
    ..Similarly, stimulation of the anesthetized GC produced no EAS or BCM response. The BCM and EAS apparently constitute a single muscle, which seems to play dual and yet synchronous roles in fecal control and sexual response...
  57. ncbi request reprint Mechanism of gastric emptying through the pyloric sphincter: a human study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Med Sci Monit 13:CR24-9. 2007
    ..The current view holds that gastric emptying is effected by the force of the antral peristaltic wave squeezing food particles through pyloric sphincter resistance. Whether this is accomplished by a reflex action was investigated...
  58. pmc Effect of rectal distension on vesical motor activity in humans: the identification of the recto-vesicourethral reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Spinal Cord Med 30:36-9. 2007
    ..Urinary retention may also occur after anorectal operations. We investigated the hypothesis that rectal distension affects vesical dilatation through a reflex action...
  59. ncbi request reprint Role of sacral ligament clamp in the pudendal neuropathy (pudendal canal syndrome): results of clamp release
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Surg 92:54-9. 2007
    ..Clinical manifestations and investigative results improved after SLC release in 80.9% of the cases. We assume that these results denote traumatization of the PN not only in the PC but also in the SLC...
  60. ncbi request reprint Electrophysiologic activity of the tunica albuginea and corpora cavernosa: possible role of tunica albuginea in the erectile mechanism
    Ahmed Shafik
    Faculty of Medicine Cairo University Department of Surgery and Experimental Research, Cairo, Egypt
    J Sex Med 4:675-9. 2007
    ..It is claimed that the tunica albuginea (TA) shares in the erectile mechanism by compressing the emissary veins passing through it. However, the TA does not contain smooth muscle fibers...
  61. ncbi request reprint The response of the corporal tissue and cavernosus muscles to urethral stimulation: an effect of penile buffeting of the vaginal introitus
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, Egypt
    J Androl 28:853-7. 2007
    ..quot; Sinusoidal and cavernosus muscles' response during coitus appears to effect a degree of tumescence for both male and female partners...
  62. ncbi request reprint Study of the duodenal contractile activity during antral contractions
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, Egypt
    World J Gastroenterol 13:2600-3. 2007
    ..To investigate the hypothesis that duodenal bulb (DB) inhibition on pyloric antrum (PA) contraction is reflex...
  63. ncbi request reprint Electromyographic activity of the anterolateral abdominal wall muscles during rectal filling and evacuation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Surg Res 143:364-7. 2007
    ..We investigated the hypothesis that the AAWMs exhibit increased electromyographic (EMG) activity on rectal distension, which presumably assists in rectal evacuation...
  64. ncbi request reprint Effect of cooling on the rectal tone
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Eur Surg Res 39:291-5. 2007
    ..Hence the identification of cold receptors sensitive to cold temperature in the rectal wall has so far not been reported in the literature. We investigated the hypothesis that rectal cooling effected an increase of the rectal tone...
  65. ncbi request reprint Duodeno-jejunal junction dyssynergia: description of a novel syndrome
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Gastroenterol 13:4112-6. 2007
    ..To investigate the hypothesis that duodeno-jejunal dyssynergia existed at the duodeno-jejunal junction...
  66. doi request reprint Tunica albuginea reefing: a novel technique for the treatment of erectile dysfunction
    Olfat El-Sibai
    Department of Surgery, Faculty of Medicine, Menoufia University, Shebin El Kom, Egypt
    J Invest Surg 24:44-8. 2011
    ..This had led to loss of the veno-occlusive mechanism of the TA and venous leakage during erection...
  67. ncbi request reprint Straining-cremasteric reflex: identification of a new reflex and its role during increased intra-abdominal pressure
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo 11121, Egypt
    Surg Radiol Anat 28:387-90. 2006
    ..The SCR may prove of diagnostic significance in neurogenic disorders provided further studies are performed in this respect...
  68. ncbi request reprint Effect of micturition on clitoris and cavernosus muscles: an electromyographic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Urogynecol J Pelvic Floor Dysfunct 19:531-5. 2008
    ..The latter two actions occurring on micturition are suggested to be mediated through a reflex called "urethro-corporocavernosal reflex" and effect a mild degree of clitoral tumescence...
  69. doi request reprint Ileocecal junction: anatomic, histologic, radiologic and endoscopic studies with special reference to its antireflux mechanism
    Ali A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Surg Radiol Anat 33:249-56. 2011
    ..The aim of the study was to perform histomorphologic, endoscopic, and radiologic studies of the ileocecal junction (ICJ). A clearer understanding of the anatomical structure of the ICJ may shed some light on its function...
  70. ncbi request reprint Study of the effect of jejuno-ileal distension on the motor activity of the stomach with evidence of "entero-gastric inhibitory reflex"
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Hepatogastroenterology 50:1966-9. 2003
    ..The current study investigated the effect of ileal and jejunal distension on the gastric motility, aiming at elucidating the possible existence of a relationship and its role in the flow through the gut...
  71. ncbi request reprint Effect of straining on the lower esophageal sphincter: identification of the "straining-esophageal reflex" and its role in gastroesophageal competence mechanism
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Invest Surg 17:191-6. 2004
    ..quot; This reflex seems to be evoked during increased intra-abdominal pressure and to effect LES contraction, thus, sharing with other factors in prevention of gastroesophageal reflux...
  72. ncbi request reprint Effect of vesical contraction on the non-sphincteric part of the urethra: recognition of vesicourethral inhibitory reflex
    Ahmed Shafik
    Department of Surgery, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int J Urol 11:213-7. 2004
    ..In this study, the hypothesis that detrusor contraction effects dilatation of the non-sphincteric part of the urethra was investigated...
  73. ncbi request reprint The effect of vaginal distension on the female urinary bladder and urethral sphincters
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Acta Obstet Gynecol Scand 86:1398-403. 2007
    ..We investigated the hypothesis that, upon vaginal distension, UB undergoes inhibited activity, while external and internal urethral sphincters (IUS) exhibit increased activity in order to guard against urine leakage during coitus...
  74. ncbi request reprint Effect of straining on perineal muscles and their role in perineal support: identification of the straining-perineal reflex
    Ahmed Shafik
    Professor and Chairman, Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Surg Res 112:162-7. 2003
    ..We investigated the hypothesis that these muscles act to support the perineum during increased intraabdominal pressure (IAP)...
  75. ncbi request reprint On the mechanism of colonic motility: the electric activation theory of colonic contraction
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo
    J Surg Res 103:8-12. 2002
    ..Shafik and A. A. Shafik, 2000, Front. Biosci. 5, b5). In the current study, we investigated the mechanism of action of the two colonic muscle coats in the motility of the gut...
  76. ncbi request reprint Study of the motile activity of the colon in rectal inertia constipation
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Gastroenterol Hepatol 17:270-5. 2002
    ..This effect was postulated to occur through the recto-colic reflex. As the colonic status in rectal inertia constipation was scarcely addressed in the literature, we investigated this point...
  77. ncbi request reprint The electrovesicogram in the overactive bladder: role in determining pathogenesis and diagnostic significance
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Urol Res 32:290-3. 2004
    ..Further studies are required to investigate the cause of the dysrhythmic pattern and the electrovesicogram is suggested as an investigative tool in OAB diagnosis...
  78. ncbi request reprint Stress urinary incontinence: new concept of pathogenesis and treatment by pudendal canal decompression
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University Faculty of Medicine, Cairo, Egypt
    Adv Exp Med Biol 539:415-40. 2003
  79. ncbi request reprint On the pathogenesis of rectocele: the concept of the rectovaginal pressure gradient
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 11121 Cairo, Egypt
    Int Urogynecol J Pelvic Floor Dysfunct 14:310-5; discussion 315. 2003
    ..A histopathologic study of the septum in rectocele seems necessary...
  80. pmc Effect of straining on diaphragmatic crura with identification of the straining-crural reflex. The "reflex theory" in gastroesophageal competence
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Gastroenterol 4:24. 2004
    ....
  81. ncbi request reprint Overactive corpus cavernosum: a novel cause of erectile dysfunction
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Andrologia 36:378-83. 2004
    ..This condition of 'overactive CC' should be considered in the diagnosis of ED. However, further studies in the pathogenesis of the condition are warranted...
  82. ncbi request reprint Mechanism of ejection during ejaculation: identification of a urethrocavernosus reflex
    A Shafik
    Department of Surgery and Experimental Research, Cairo University, Egypt
    Arch Androl 44:77-83. 2000
    ..The latter presumably propels the semen from the posterior to the pendulous urethra. It is suggested that the urethrocavernosus reflex be included in current andrologic investigations for patients with ejaculatory disorders...
  83. ncbi request reprint Study of the rectal electric activity of the uninhibited rectal detrusor (overactive rectum): a new concept of pathogenesis
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Spinal Cord Med 28:64-8. 2005
    ..We investigated the hypothesis that the abnormal rectal contractility in URDS may be caused by deranged rectal electric activity...
  84. ncbi request reprint Effect of lower esophageal sphincter distension and acidification on esophageal pressure and electromyographic activity: the identification of the "sphinctero-esophageal excitatory reflex"
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Ann Thorac Surg 79:1126-31; discussion 1131. 2005
    ..We investigated the hypothesis that lower esophageal sphincter (LES) dilatation rather than the refluxed acid affected reflex increase in the esophageal peristaltic activity aiming at clearing the esophagus of the refluxed acid...
  85. ncbi request reprint Effect of vaginal distension on anorectal function: identification of the vagino-anorectal reflex
    Ahmed Shafik
    Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Acta Obstet Gynecol Scand 84:225-9. 2005
    ..We investigated the hypothesis that the anal sphincters and the rectum respond to penile thrusting in a way that prevents gas and fecal leakage during sexual intercourse...
  86. ncbi request reprint Overactive bladder inhibition in response to pelvic floor muscle exercises
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Urol 20:374-7. 2003
    ..The results of the current study encourage the treatment of overactive bladder with PFM contractions...
  87. ncbi request reprint The motor efficacy of the artificial colonic pacemaker in colonic inertia patients
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 7:b6-13. 2002
    ..Ex-pacemaker stimulation presumably leads to local activation of interstitial cells of Cajal and segmental step-wise contraction...
  88. ncbi request reprint Role of the rectosigmoid pacemaker and electric activity in rectal motility: mechanism and clinical significance
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo
    Electromyogr Clin Neurophysiol 42:377-83. 2002
    ..We hypothesized that the RSP and electric waves are responsible for rectal motility. This hypothesis was investigated...
  89. ncbi request reprint Effect of urethral dilation on vesical motor activity: identification of the urethrovesical reflex and its role in voiding
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Urol 169:1017-9. 2003
    ..We investigated the hypothesis that mild urethral distention, which presumably occurs during the passage of urine through the urethra, stimulates stretch receptors in the urethral wall, leading reflexively to vesical contraction...
  90. ncbi request reprint Treatment of irritable bowel syndrome with colonic pacing: evaluation of pacing parameters required for correction of the "tachyarrhythmia" of the IBS
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Hepatogastroenterology 51:1708-12. 2004
    ..In this communication we tried to define the adequate pacing parameters necessary for normalization of the tachyarrhythmic pattern of the electric waves in IBS...
  91. ncbi request reprint Role of positive anorectal feedback in rectal evacuation: the concept of a second defecation reflex: the anorectal reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Spinal Cord Med 26:380-3. 2003
    ....
  92. ncbi request reprint Do vesical and voided urine have identical compositions?
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Scand J Urol Nephrol 38:243-6. 2004
    ..In view of the concept that the urothelium is a functioning epithelium, we investigated the hypothesis that the composition of urine is modified as it passes through the urethra from the urinary bladder to the exterior...
  93. ncbi request reprint Rectal cooling test in the differentiation between constipation due to rectal inertia and anismus
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Tech Coloproctol 11:39-43. 2007
    ..Therefore, we studied the hypothesis that the rectal cooling test (RCT) can effectively be used to differentiate between those two forms of constipation...
  94. ncbi request reprint Transmission of rectal electric waves: is it through circular or longitudinal smooth muscle layers or both?
    A Shafik
    Department of Surgery and Experimental Research, Cairo University, Egypt
    Arch Physiol Biochem 109:127-34. 2001
    ..This concept is evidenced not only by the current findings but also by the histologic structure of the rectal musculature being of the unitary type of smooth muscles...
  95. ncbi request reprint Rectal inhibition by inferior rectal nerve stimulation in dogs: recognition of a new reflex--the 'voluntary anorectal inhibition reflex'
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Eur J Gastroenterol Hepatol 13:413-8. 2001
    ..The effect of inferior rectal nerve (IRN) stimulation on the rectum was studied, postulating that nerve stimulation might inhibit rectal contractility and could thus be used in the management of defecation disorders...
  96. ncbi request reprint Electromyographic study of ejaculatory mechanism
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int J Androl 32:212-7. 2009
    ..Changes in LET or evoked response would indicate a defect in the reflex pathway. The GCVR might act as an investigative tool in diagnosing erectile dysfunction, provided further studies are performed in this respect...
  97. ncbi request reprint Injured external anal sphincter in erectile dysfunction
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Andrologia 33:35-41. 2001
    ..Repair of the external anal sphincter provided a cure for faecal incontinence and erectile dysfunction. Anorectal disorders are believed to affect erectile function, a relationship that needs further investigation...
  98. ncbi request reprint Role of the enteric nervous plexus in rectal motile activity: an experimental study
    A Shafik
    Department of Surgery and Experimental Research, Cairo University, Egypt
    J Invest Surg 14:275-81. 2001
    ..This suggests that the enteric plexus has no direct action on the rectal motile activity but mediates the rectal reflex actions. This concept might explain some of the hitherto unknown mechanisms of rectal dyssynergia syndromes...
  99. ncbi request reprint Identification of c-kit-positive cells in the human prostate: the interstitial cells of Cajal
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 51:345-51. 2005
    ..The study of the integrity of these cells may prove to be a useful investigative tool in the diagnosis of prostatic diseases and in the planning of an appropriate treatment...
  100. ncbi request reprint Electrophysiologic identification of the location of the colonic pacemakers. A human study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 7:b1-5. 2002
    ..The electric waves appear to be responsible for conducting the colonic motor activity. We postulate that disordered colonic pacemakers may produce segmental or total colonic inertia, a proposition that needs further investigation...
  101. ncbi request reprint Study of the effect of cervix uteri buffeting on the vaginal musculature with identification of the cervico-vaginal inhibitory reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 11121 Cairo, Egypt
    Arch Gynecol Obstet 270:165-9. 2004
    ..During penile thrusting, the penis repeatedly buffets the cervix uteri (CU). We investigated the hypothesis that CU stimulation induces a change in the motor activity of the vaginal wall musculature...