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Graefe's Archive for Clinical and Experimental Ophthalmology - Retinal microvascular endothelial dysfunction is thought to be of importance in the development of ocular vascular diseases....  相似文献   
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OBJECTIVES: We analyzed the methods and outcomes of urethroplasty in men with complex urethral disruptions. METHODS: The medical records of 40 men with complex urethral disruptions were analyzed. Surgical methods were individualized according to stricture location, severity and length of the stricture, bladder neck characteristics and presence of complicating factors. Patients were divided into four groups based on the above characteristics. RESULTS: End-to-end urethroplasty performed in six patients with short bulbar strictures (<3 cm) was successful in all. Elaborated perineal repair was performed in 10 patients with intermediate (3-6 cm) strictures with or without complicating factors. Elaborated perineal repair with urethral substitution was performed in nine patients with long segment stricture (>6 cm). Abdominal transpubic repair was successfully applied to patients with rectourethral fistula or lacerated bladder neck. Success rate of anastomotic urethroplasty was 95% while over all success rate was 85%. CONCLUSION: Guidelines for urethral reconstruction of complex urethral disruptions are predicated on stricture length, location, bladder neck characteristics and associated complicating factors. End-to-end urethroplasty with stricture excision is highly reliable for short strictures for which previous operative repair have failed. Elaborated perineal repair is extremely versatile for intermediate and longer strictures with associated complicating factors. Abdominal transpubic urethroplasty is effective for patients with rectourethral fistula or lacerated bladder neck.  相似文献   
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Spontaneous gall bladder perforation in infants is rare. We report a 3-month-old male infant who presented with progressive abdominal distension, low-grade fever, bilateral hydrocele and acholic stools. Ultrasonography showed free fluid in the peritoneal cavity, which was bile-stained on paracentesis. Surgical exploration revealed sterile biliary peritonitis and a gangrenous gall bladder. Partial cholecystectomy with external biliary drainage resulted in satisfactory recovery.  相似文献   
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OBJECTIVE: To develop biomechanical variable models for driver skull base injury mechanisms in motor vehicle collisions. STUDY DESIGN: Retrospective database review. METHODS: Biomechanical collision variables and safety restraint data were analyzed for Crash Injury Research and Engineering Network skull base trauma subjects enrolled during the recruitment period between 1996 and 2005. RESULTS: For drivers satisfying inclusion criteria (n = 26), injury resulted from contact with rigid vehicle structural elements in 82%, and occurred in 50% despite both seatbelt and air bags. Eight percent used neither seatbelts nor air bags. Seventy-two percent involved vector velocity changes greater than 30 mph. The relative morbidity of skull base injuries was also detailed. CONCLUSION: The majority of driver skull base injuries resulted from contact with rigid vehicle structural elements in high velocity crashes. Seatbelt and air bag use could not be definitively correlated with skull base injury. CLINICAL SIGNIFICANCE: Injury mechanism models can be developed that facilitate further investigations to determine impact and scope on a national scale.  相似文献   
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Objective. This prospective study was undertaken to evaluate the safety and efficacy of neodymium:yttrium-aluminium-garnet (Nd:YAG) laser for treatment of symptomatic benign prostatic hyperplasia (BPH).Methods. A total of 61 patients at a mean age of 71.6 years with symptomatic bladder outlet obstruction due to BPH underwent transurethral evaporation of prostate (TUEP) using Nd:YAG laser. Twelve of the patients were experiencing acute retention. Pre- and postoperative evaluation consisted of American Urological Association (AUA) symptom questionnaire and a sexual function questionnaire, uroflowmetry, postvoid residual urine, electrolytes, blood urea nitrogen, creatinine, hematocrit, and prostate volume estimation by transrectal ultrasound. TUEP was achieved by employing a side-firing Nd:YAG laser fiber with a durable quartz reflector and high-power density (Ultraline, Heraeus LaserSonics, Milpitas, CA) that was used in a contact mode.Results. All patients have been evaluated for three months, 26 for six rnonths, and 7 for twelve months. Mean prostatic size was 41.1 g. The mean improvement in symptom scores at one, three, six, and twelve months was 69.8 percent, 70.9 percent, 76.0 percent, and 70.9 percent, respectively (P = < 0.0001). The mean increase in maximum uroflow at one, three, six, and twelve months was 63.4 percent, 66.7 percent, 41.94 percent, and 164.52 percent, respectively (P = < 0.0001). There was no instance of significant fluid absorption or bleeding. The duration of postoperative catheterization was two days in 43 patients, three to seven days in 16 patients, and two to three weeks in 2 patients. There were no deaths. All patients evaluated by TRUS at six months had open channeling defects. Videocystoscopy performed in 16 patients at two to three months postoperatively revealed tissue slough. At repeat cystoscopy in these patients at six months, the prostatic fossa was completely healed with no evidence of tissue slough.Conclusions. It is concluded that the technique of TUEP using Nd:YAG laser is safe and, in preliminary results, appears apparently effective in the management of BPH.  相似文献   
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Cerebral blood flow (CBF) and other physiological variables were measured repeatedly for up to 10 days after severe head injury in 102 patients, and CBF levels were related to outcome. Twenty five of the patients had a reduced CBF [mean (SD) 0.29 (0.05) ml/g/min]; 47 had a normal CBF, (0.41 (0.10) ml/g/min); and 30 had a raised CBF (0.62 (0.14) ml/g/min). Cerebral arteriovenous oxygen differences were inversely related to CBF and averaged 2.1 (0.7) mumol/ml in the group with reduced CBF, 1.9 (0.5) mumol/ml in the group with normal CBF, and 1.6 (0.4) mumol/ml in the group with raised CBF. Patients with a reduced CBF had a poorer outcome than patients with a normal or raised CBF. Mortality was highest in patients with a reduced CBF, and was 32% at three months after injury, whereas only 21% of the patients with a normal CBF and 20% of the patients with a raised CBF died. There were no differences in the type of injury, initial score on the Glasgow Coma Scale, mean intracranial pressure (ICP), highest ICP, or the amount of medical treatment required to keep the ICP less than 20 mm Hg in each group. Systemic factors did not significantly contribute to the differences in CBF among the three groups. A logistic regression model of the effect of CBF on neurological outcome was developed. When adjusted for variables which were found to be significant confounders, including age, initial Glasgow Coma Score, haemoglobin concentration, cerebral perfusion pressure and cerebral metabolic rate of oxygen, a reduced CBF remained significantly associated with an unfavourable neurological outcome.  相似文献   
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A mother affected with Apert's syndrome was diagnosed by ultrasound scan at 16-17 weeks to have a fetus similarly affected. The typical features of acrocephaly and symmetrical syndactyly were seen. This is probably the first time that this condition has been diagnosed at such a gestation by ultrasound scan. The patient decided to continue the pregnancy, and intrauterine death occurred at 34 weeks. The diagnosis was confirmed by pathological examination.  相似文献   
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