Ahmed Shafik

Summary

Affiliation: Cairo University
Country: Egypt

Publications

  1. 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
  2. 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
  3. 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
  4. 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
  5. 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
  6. 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
  7. ncbi request reprint Diverticular disease: electrophysiologic study and a new concept of pathogenesis
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 111231 Cairo, Egypt
    World J Surg 28:411-5. 2004
  8. 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
  9. ncbi request reprint Vesical pacing: pacing parameters required for normalization of vesical electric activity in patients with overactive bladder
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 9:995-9. 2004
  10. ncbi request reprint 'Objective' assessment of rectal sensation: a novel approach
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 9:159-63. 2004

Detail Information

Publications79

  1. 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...
  2. 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...
  3. 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...
  4. 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...
  5. 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...
  6. 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...
  7. ncbi request reprint Diverticular disease: electrophysiologic study and a new concept of pathogenesis
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 111231 Cairo, Egypt
    World J Surg 28:411-5. 2004
    ..The similarity between early DD and the irritable bowel syndrome suggests that DD is an advanced stage of the irritable bowel syndrome; studies are required to investigate this hypothesis further...
  8. 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...
  9. ncbi request reprint Vesical pacing: pacing parameters required for normalization of vesical electric activity in patients with overactive bladder
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 9:995-9. 2004
    ..Vesical pacing is suggested to be used as a therapeutic tool for the treatment of the OAB...
  10. ncbi request reprint 'Objective' assessment of rectal sensation: a novel approach
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 9:159-63. 2004
    ..Further studies are required to investigate the role of this reflex in defection and sympathetic disorders...
  11. ncbi request reprint The electrovaginogram: study of the vaginal electric activity and its role in the sexual act and disorders
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, 11121 Cairo, Egypt
    Arch Gynecol Obstet 269:282-6. 2004
    ..We investigated the hypothesis that the vagina generates electric waves which effect vaginal contraction during penile thrusting...
  12. ncbi request reprint Colonic pacing: a therapeutic option for the treatment of constipation due to total colonic inertia
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Surg 139:775-9. 2004
    ..The treatment of constipation caused by total colonic inertia is problematic and its results are unsatisfactory. We speculated that colonic pacing would initiate electric activity in the inertial colon and effect rectal evacuation...
  13. ncbi request reprint Does the crural diaphragm share in the contractile activity of the costal diaphragm? The concept of an "autonomous esophageal crus" and its role in esophageal competence
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Med Sci Monit 10:BR268-72. 2004
    ..We investigated the hypothesis that the esophageal crus (EC, part of the crus surrounding the esophagus) is an "individual muscle" and does not share in the contractile activity of the costal diaphragm (CD)...
  14. 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...
  15. ncbi request reprint Oviduct contractile response to vaginal distension: identification of vagino-tubal reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, 2 Talaat Harb Street, Cairo, 11121, Egypt
    Arch Gynecol Obstet 271:148-51. 2005
    ..We investigated the hypothesis that vaginal distension effects oviduct contraction, which assists in ovum transport along the oviduct...
  16. pmc Electroesophagogram in gastroesophageal reflux disease with a new theory on the pathogenesis of its electric changes
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Eygpt
    BMC Surg 4:13. 2004
    ....
  17. 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
    ....
  18. ncbi request reprint Electric activity of the gut in ulcerative colitis and Crohn's disease: electromyography as a tool for differentiating between the two conditions in the early stage
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Med Sci Monit 10:CR572-6. 2004
    ..We investigated the hypothesis that a difference in the electric pattern of the gut exists between UC and CD which may assist in the differentiation between the 2 conditions in the early stage...
  19. ncbi request reprint Electromotor activity of the cecum and ascending colon: the concept of 'individual pacemakers'
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Eur Surg Res 36:308-12. 2004
    ..This hypothesis was investigated in the current study...
  20. ncbi request reprint Electrocavernosogram in erectile dysfunction: a diagnostic tool
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Androl 50:317-25. 2004
    ..We suggest that electrocavernosography has the potential to function as an investigative tool in diagnosing the type of ED provided further studies are performed to verify the described findings...
  21. ncbi request reprint Vesical pacing in patients with overactive bladder: technique and results
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int Urol Nephrol 36:29-34. 2004
    ..We investigated the hypothesis that vesical pacing of the OAB might improve not only the vesical electric activity but also the symptoms...
  22. ncbi request reprint Response of the labia majora and minora to clitoral stimulation
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Int J Gynaecol Obstet 86:401-2. 2004
  23. ncbi request reprint Electric activity of the colon in irritable bowel syndrome: the 'tachyarrhythmic' electric pattern
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Gastroenterol Hepatol 19:205-10. 2004
    ..Because the condition is related to motility disturbance, the hypothesis that a disorder of the colonic electromyographic activity is responsible for the colonic motile disorders in irritable bowel syndrome, was investigated...
  24. 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...
  25. 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...
  26. 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...
  27. ncbi request reprint Identification of interstitial cells of Cajal in the human rectum
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 9:2848-51. 2004
    ..The role of these cells in normal physiologic and pathologic conditions of the rectum needs further studies...
  28. ncbi request reprint Videodefecography: a study of the rectal motile pattern
    A Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Surg Radiol Anat 25:139-44. 2003
    ..Two types of contraction waves were observed: "complete" which produced rectal evacuation, and "incomplete" which failed to effect evacuation. Physiologic intussusception or rectocele were seen in a few subjects...
  29. ncbi request reprint Colonic pacing in patients with constipation due to colonic inertia
    Ahmed Shafik
    Department of Surgery and Experimental Reseearch, Faculty of Medicine, Cairo University, Egypt
    Med Sci Monit 9:CR191-6. 2003
    ..We investigated the hypothesis that the absence of electric activity in TCI is due to non-functioning pacemakers and that their stimulation produces colonic motility and defecation...
  30. ncbi request reprint Role of sympathetic innervation in the defecation mechanism: a novel concept of its function
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Spinal Cord Med 26:150-4. 2003
    ..Because the role of sympathetic innervation in the defecation mechanism is still vague and unidentified, this study was performed to investigate this issue...
  31. ncbi request reprint On the pathogenesis of gastroesophageal reflux: the concept of gastroesophageal dyssynergia
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Egypt
    J Thorac Cardiovasc Surg 130:401-7. 2005
    ..We investigated the hypothesis that the esophagogastric junction incompetence results from failure of the gastric distention to produce the lower esophageal sphincter and crural diaphragm contraction caused by a disordered reflex action...
  32. 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)...
  33. ncbi request reprint Role of positive urethrovesical feedback in vesical evacuation. The concept of a second micturition reflex: the urethrovesical reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Urol 21:167-70. 2003
    ..The role of this reflex in the pathogenesis of micturition disorders needs to be studied...
  34. pmc Anorectal motility in patients with achalasia of the esophagus: recognition of an esophago-rectal syndrome
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    BMC Gastroenterol 3:28. 2003
    ..During my study of constipation, I encountered patients who had achalasia of the esophagus (AE) as well. The possibility of an existing relationship between the 2 conditions was studied...
  35. ncbi request reprint Transcutaneous electrocavernosography: a tool for recording the electromyographic activity of the corpora cavernosa
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Urol 174:629-31. 2005
    ..We investigated the hypothesis that transcutaneous electrocavernosography (ECG) would register electric waves similar to those recorded by the needle ECG but noninvasively...
  36. ncbi request reprint Electric activity of the colon in subjects with constipation due to total colonic inertia: an electrophysiologic study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Arch Surg 138:1007-11; discussion 1011. 2003
    ..The APs are claimed to be responsible for colonic motor activity...
  37. ncbi request reprint Physioanatomic study of the diaphragmatic crura: the identification of autonomous "gastroesophageal sphincter"
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Invest Surg 18:135-42. 2005
    ..We call this muscle "striated gastroesophageal sphincter"...
  38. 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...
  39. 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...
  40. 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...
  41. 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...
  42. 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'...
  43. 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...
  44. 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...
  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 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...
  47. 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...
  48. 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...
  49. 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...
  50. 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...
  51. ncbi request reprint Parasympathetic extrinsic reflex: role in defecation mechanism
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    World J Surg 26:737-40; discussion 741. 2002
    ..The difference between them in inducing defecation might be significant to our understanding the defecation act in the neurogenic rectum, a point that needs further study...
  52. 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...
  53. 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...
  54. 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...
  55. ncbi request reprint Colonic pacing in the treatment of patients with irritable bowel syndrome: technique and results
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Front Biosci 8:b1-5. 2003
    ..No complications were encountered and the method was well accepted and tolerated. Further studies on a large group of patients are required...
  56. 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...
  57. 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...
  58. ncbi request reprint Electrophysiologic identification of the location of the colonic pacemakers in humans: further study
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    J Invest Surg 16:289-97. 2003
    ..These suggestions need to be further studied...
  59. 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...
  60. 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...
  61. 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...
  62. 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...
  63. 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
    ....
  64. 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...
  65. 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...
  66. 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...
  67. 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...
  68. 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...
  69. 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...
  70. 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...
  71. ncbi request reprint Stress, urge, and mixed types of partial fecal incontinence: pathogenesis, clinical presentation, and treatment
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Cairo, Egypt
    Am Surg 73:6-9. 2007
    ..Each type has its own etiology and symptoms, and requires individual treatment. Biofeedback succeeded in treating the majority of SFI and UFI patients. Surgical correction of the anal sphincter was performed after biofeedback failure...
  72. pmc Electrophysiological study of the rectosigmoid canal: evidence of a rectosigmoid sphincter
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Anat 200:517-21. 2002
    ..The greater increase of the electrical activity and pressure of the rectosigmoid canal upon electrostimulation, compared to that of the SC or R, strongly supports the presence of a rectosigmoid sphincter...
  73. ncbi request reprint Role of the longitudinal smooth muscle coat in the ileal motile activity: evidence of ileo-ileal inhibitory reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faculty of Medicine, Cairo University, Egypt
    J Gastroenterol Hepatol 17:1267-71. 2002
    ..The role of the longitudinal smooth muscle of the small intestine in gut motility is poorly understood; this point was investigated in the current study...
  74. ncbi request reprint Effect of colonic distention on ileal motor activity with evidence of coloileal reflex
    Ahmed Shafik
    Department of Surgery and Experimental Research, Cairo University, Cairo, Egypt
    J Gastrointest Surg 7:701-5. 2003
    ..quot; Whenever the right colon is distended with a substantial volume of chyme that increases the intraluminal pressure, it is suggested that ileal relaxation occurs, which delays the emptying of chyme from the ileum...
  75. ncbi request reprint Effect of perineal compression on vesical motor activity
    Ahmed Shafik
    Department of Surgery and Experimental Research, Faulty of Medicine, Cairo University, Egypt
    Scand J Urol Nephrol 37:348-51. 2003
    ..It has been reported that digital pressure on the perineum inhibits bladder contraction; however, the mechanism is not fully understood. We investigated the hypothesis that this mechanism may be reflex in nature...
  76. 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
  77. 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...
  78. ncbi request reprint Rectocolonic excitatory reflex or rectocolonic inhibitory reflex?
    Ahmed Shafik
    Dis Colon Rectum 48:1671-2. 2005
  79. ncbi request reprint Colonic pacing in the control of colonic and rectal motile activity
    Ahmed Shafik
    Dis Colon Rectum 47:545-6; author reply 546. 2004