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61.
PURPOSE: We review the results of 132 cases of congenital and acquired penile curvature corrected with our 16 or 24-dot, minimal tension technique using multiple parallel plications performed under papaverine induced erection. MATERIALS AND METHODS: Chart and telephone interviews were conducted on 132 consecutive patients 16 to 79 years old who underwent penile plication between December 1995 and November 2000. Patient data as well as outcomes were analyzed. RESULTS: We were unable to contact 8 patients. Of the patients 16 had congenital penile curvature, including 4 in whom the Nesbit procedure performed elsewhere had failed, and 116 had Peyronie's disease, including 8 in whom a previous Nesbit procedure had failed. Preoperative complaints included persistent penile pain with erection for more than 1 year in 15 of 132 cases, difficult intercourse or partner discomfort in 106 and poor self-image in 11. Curvature ranged from 30 to 120 degrees. Erections were evaluated preoperatively with duplex ultrasound after intracavernous injection and self-stimulation. Of the patients 63% had good erections, 25% moderate erections requiring sildenafil and 12% poor erections requiring injection therapy. Foreskin edema necessitating subsequent circumcision and an organized hematoma requiring evacuation occurred in 1 case each. At 6 months 93% of patients reported straight erections and 7% reported almost straight but acceptable erections. Recurrence of curvature was reported by 15% of patients at a mean of 2.6 years of followup. Four patients reported worsening of erectile function after the procedure. CONCLUSIONS: Penile plication is a simple, safe method to correct congenital and acquired penile curvature. Using a minimal tension parallel plication technique, excellent durable results can be attained. This simplified repair avoids the neurovascular bundles and has a minimal to no detrimental affect on erectile function. Preoperative counseling must be given regarding penile shortening and the palpable small bumps from the nonabsorbable sutures.  相似文献   
62.
PURPOSE: Using an animal model we studied the long-term effects of ovariectomy and simulated birth trauma in the development of apoptosis as well as the urodynamic, histological and ultrastructural findings 9 months after such procedures. MATERIALS AND METHODS: A total of 24 pregnant Sprague-Dawley female rats were used. Immediately after delivery 14 animals underwent vaginal ballooning and ovariectomy, while the remaining 10 served as controls. At 9 months the animals underwent urodynamic evaluation, which included the urethral pressure profile. The rats were then sacrificed and urogenital tissue was obtained for immunostaining using terminal deoxynucleotidyl transferase mediated deoxyuridine triphosphate nick end-labeling, histomorphometry evaluation and electron microscopy. RESULTS: Immunostaining demonstrated a significant increase in the apoptotic index in the urethra of castrated/ballooning rats with a predominance in the submucosa layer. Maximum urethral closure pressure was significantly lower in that group, although there was no correlation of apoptosis with maximum urethral closure pressure measurement. Urodynamic evaluation revealed only discrete alterations in cystometric parameters. Morphometric evaluation showed increased connective tissue in the vagina. Electron microscopy of urethral smooth muscle demonstrated altered cellular shape, increased intercellular space with collagen deposition and some degeneration of the mitochondria. CONCLUSIONS: Apoptosis in the urethra occurs 9 months after castration and simulated birth trauma. However, this finding was not seen in the muscle layers or in other urogenital tissues. Some ultrastructural changes also occurred that may explain some symptoms that women have after vaginal childbirth and menopause.  相似文献   
63.
The induction of an antibody response to amyloid beta (Abeta) peptide has become a strategy for the treatment of Alzheimer's disease (AD). This has proven effective in reducing the plaque burden in transgenic mice that develop Abeta plaques similar to human AD patients. The mechanism for enhanced clearance of Abeta is partly due to the interaction of immunoglobulin Fcgamma receptor-expressing microglia and specific antibody-opsonized Abeta deposits. This interaction can stimulate Fcgamma receptor-mediated phagocytosis, but also results in inflammatory activation of these cells. Consequently, interaction of microglia with antibody-antigen complexes could exacerbate the existing inflammation in the brains of AD patients. In this study, we used substrate-bound Abeta and cultured human microglia from AD and non-demented cases to model interaction of microglia and antibody-opsonized plaques in AD brains. Enhanced production of tumor necrosis factor-alpha, macrophage colony stimulating factor, interleukin-10, and superoxide ions was detected. We also demonstrated enhanced uptake of opsonized Abeta by microglia, which was reduced significantly in the presence of excess IgG, indicative of the involvement of Fcgamma receptor-mediated mechanisms. Human microglia were shown in this study to express mRNA for Fcgamma receptors I, IIa, IIb, and III. The expression of Fcgamma receptor II was augmented by proinflammatory stimulation. These results suggest that initial interactions of human microglia with antibody-opsonized amyloid could result in increased inflammation. The consequence of this on inflammatory pathology in AD brains needs to be considered before immunization is used as a strategy for treating AD.  相似文献   
64.
65.
OBJECTIVE: To elucidate the effect of testosterone on penile innervation. Materials and methods Three groups of six rats each were assessed; two groups (1 and 2) were castrated and the third (group 3) underwent a sham operation (control). Eight weeks after castration, group 2 received a subcutaneous injection with testosterone. At 8 weeks, the rats in group 1 and 3 underwent a final functional analysis while those in group 2 did so at 12 weeks. The evaluation included a subcutaneous injection with apomorphine to study centrally mediated erection, and cavernosal nerve electrostimulation and papaverine injection to study peripherally mediated erection. At death a penile mid-shaft specimen was taken for NADPH-diaphorase staining. RESULTS: In the apomorphine study, castration resulted in significantly fewer yawns and erections than in the control, and those in group 2 significantly better central erectile function than in the controls. The mean (SEM) number of nitric oxide synthase (NOS)-containing nerve fibres in the corpora cavernosa and both dorsal nerves of castrated rats, at 46.2 (9.1) and 203 (32.1), respectively, were significantly lower than in rats in group 2, at 84.1 (11.2) and 300.6 (17.1), and than in the controls, at 88.6 (10.9) and 306.3 (22.9), respectively. The intracavernosal pressure decreased significantly in the absence of testosterone, both after electrostimulation and intracavernosal papaverine injection. However, there was no difference between the control and group 2 rats in either the number of NOS-containing nerve fibres or in the peripheral erectile functional study. CONCLUSIONS: Testosterone acts on the nervous system to mediate erection; when it is absent there may be down-regulation of both the production and activity of NO, thereby decreasing the response to peripheral stimulation via the NO pathway. The restoration of erectile function seen in rats in group 2 supports this phenomenon. Delayed testosterone replacement has no detrimental effect on the restoration of the erectile mechanism after castration.  相似文献   
66.
Summary With the advent of echocardiography, total anomalous pulmonary venous connection (TAPVC) can be readily diagnosed without much difficulty. However, noninvasive detection of the presence of pulmonary venous obstruction in TAPVC remains a difficult issue. During a 5.5-year period, 42 patients were found to have TAPVC by catheterization, surgery, and/or autopsy: 17 had supracardiac drainage, 13 paracardiac drainage, nine infracardiac drain-age, and three mixed drainage. Obstruction to pulmonary venous drainage was found in 24 patients (57%). Patients with right isomerism tended to have a higher incidence of pulmonary venous obstruction than those with the usual atrial arrangement (80% vs. 44%,p<0.05). Color Doppler combined with cross-sectional echocardiography provided accurate delineation of drainage sites in 93% cases (39 of 42). Among the 39 cases with correct echocardiographic delineation of the drainage site, obstruction was detected by echocardiography in 22 cases with a sensitivity of 100% (22 of 22) and a specificity of 85% (17 of 20). Therefore, complete echocardiography, including cross-sectional images and color Doppler proved to be a reliable tool in the detection of drainage sites and pulmonary venous obstruction in TAPVC.  相似文献   
67.
Castration and erection. An animal study   总被引:1,自引:0,他引:1  
Castrated dogs (n = 3) need a much higher threshold level of energy to induce erection by electrical stimulation of the cavernous nerve than noncastrated animals (n = 24). In addition the resulting quality of erection, measured as maximal intracavernous pressure (pCC) versus peak systolic blood pressure (BP), was weaker in castrated dogs (pCC = 57% of BP on average) than in noncastrated dogs (pCC = 80% of BP on average). A high venous outflow from the corpora cavernosa in castrated dogs can also explain the shorter duration of erection. This experimental model excludes the interference of subjective factors, such as erotic stimuli and libido on erection, and it seems that androgen deficiency has a direct effect on the neurophysiology of the erectile tissues resulting in a higher tonus of the detumescence factors, which can be explained by an incomplete relaxation of the sinusoidal smooth muscle.  相似文献   
68.
During a 13-month period, 13 patients with asplenia syndrome were evaluated with MRI for cardiovascular and visceral anomalies. The MR images were reviewed for the presence of hiatus hernia which was found in three patients. One of the remaining ten patients with no MRI evidence of hiatus hernia was diagnosed as having gastro-oesophageal reflux and hiatus hernia by an oesophagogram and 24-h pH monitoring. This patient had undergone fundoplication prior to MRI. Out of the 13 patients (31%) with asplenia syndrome, 4 had hiatus hernia. It appears that among patients with the asplenia syndrome, hiatus hernia is a frequent finding. Recurrent pneumonia or bronchiolitis in patients with asplenia syndrome requires evaluation for the presence of hiatus hernia and gastro-oesophageal reflux.  相似文献   
69.
BACKGROUND: Intraoperative transesophageal echocardiography (TEE) is useful in evaluating the repair of lesions in patients with congenital heart disease. But the use of TEE in infants with total anomalous pulmonary venous connection (TAPVC) remains unclear. We reviewed the safety and efficacy of intraoperative TEE during TAPVC repair. METHODS: Twenty-eight consecutive 1 day to 7 month-old infants with TAPVC (14 supracardiac, six intracardiac and eight infracardiac type) had surgical repair with intraoperative TEE monitoring. RESULTS: Four patients received immediate surgical revision after primary surgery for residual anastomotic stenosis diagnosed by TEE. In addition, two unsuspected ventricular septal defects and three persistent ductus arteriosus were detected before surgery. Eight infants (29%) had hypotension and hypoxemia associated with TEE probe insertion before surgery, but this hemodynamic disturbance returned to baseline value after withdrawing the TEE probe from the esophagus. However, these eight patients had uneventful TEE probe insertion following sternotomy. The mechanism was probably because of the reduction of intrathoracic pressure when the chest was opened. CONCLUSIONS: TEE probe insertion in TAPVC patients may pose a potential risk of compression of pulmonary venous confluence resulting in hemodynamic instability. Therefore, we suggest that the use of TEE in such TAPVC patients appears to be safer after sternotomy.  相似文献   
70.
OBJECTIVE: To describe a technique of externally bulking the urethra with a soft-tissue graft before placing another artificial urinary sphincter (AUS), as when placing another AUS for recurrent male stress urinary incontinence (SUI) other manoeuvres, e.g. placing a tandem cuff or transcorporal cuff, must be used to obtain urinary continence in an atrophic urethra, and each is associated with morbidity. PATIENTS AND METHODS: From January 2003 to July 2004, five patients (mean age 74 years, range 62-84) treated by radical prostatectomy were referred for recurrent SUI after placing an AUS (four, including one with urethral erosion) or a male sling (one, with a resulting atrophic urethra). Each patient was treated with an external urethral bulking agent (Surgisis) ES, Cook Urological, Spencer, Indiana) and had an AUS placed. RESULTS: In each patient the greatest urethral circumference was <4 cm. To place a functional 4 cm cuff, the diameter of the urethra was enhanced by wrapping it with Surgisis ES. Continence was significantly improved in all patients except one 84-year-old man who had the replanted artificial sphincter removed because of erosion 14 months after surgery. CONCLUSION: In cases of severe recurrent SUI from urethral atrophy after placing an AUS, externally bulking the urethra with Surgisis ES before placing another AUS is well tolerated, and gives satisfactory results.  相似文献   
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