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991.
992.
Metastatic spermatocytic seminoma is an extremely rare disease with only one documented case in literature. We present another patient with metastatic disease confirmed by histological work-up after laparoscopic retroperitoneal lymph node dissection (L-RPLND).  相似文献   
993.
994.
OBJECTIVE: To evaluate the oncological efficacy of reducing cisplatin-based chemotherapy to two cycles in patients with low-volume retroperitoneal stage II nonseminomatous germ cell tumours (NSGCTs). PATIENTS AND METHODS: From October 1988 until January 2004, two cycles of cisplatin-based chemotherapy were administered in 59 patients with low-volume retroperitoneal clinical stage II NSGCT (retroperitoneal mass of <5 cm in diameter). Regardless of remission detected on computed tomography, 6 weeks after chemotherapy the patients had a retroperitoneal lymph node dissection (RPLND) to assess residual active tumour or mature teratoma (open modified bilateral RPLND until 1992, then laparoscopic unilateral template RPLND). RESULTS: The chemotherapy was effective, as no active tumour was found in any of RPLND specimens. Mature teratoma was present in lymphatic tissue in 23 of 59 patients (39%). In one patient there was a pulmonary recurrence, successfully treated with cisplatin-based salvage chemotherapy. One patient died from an accident but with no evidence of tumour, and 56 patients remained free of disease at a mean follow-up of 98.6 months. No patient died from disease. All patients had antegrade ejaculation after laparoscopic RPLND, as did 89% after open RPLND. CONCLUSION: In this pilot study, the oncological efficacy of two cycles of cisplatin-based chemotherapy was favourable, but this approach still cannot be recommended as a standard treatment for patients with low-volume retroperitoneal stage II disease. RPLND after chemotherapy has diagnostic (detecting active tumour) and therapeutic (removing mature teratoma) value and can be done laparoscopically. Based on the present results a prospective randomized trial seems reasonable.  相似文献   
995.
OBJECTIVE: To gain more insight into the histology of small incidental intratesticular lesions and evaluate the need for surgical management, as exploratory surgery is the only way to exclude malignancy in testicular tumours. PATIENTS AND METHODS: Between September 2000 and April 2005, incidental intratesticular masses of < or = 5 mm in diameter were found in 20 men undergoing scrotal ultrasonography for reasons other than suspected testicular tumour. After staging, an organ-sparing approach including frozen-section analysis was used to obtain histological data. RESULTS: The mean diameter of the detected tumour masses was 3.5 mm, and the mean (range) age of the patients was 36.4 (26-58) years. Four men (20%) had orchidectomy because the tumours were found to be malignant; the resected specimens yielded multifocal testicular intraepithelial neoplasia (TIN) in all patients and additional seminomatous tumour cells elsewhere in the testis in one. Frozen-section results were false-negative in one patient and he had orchidectomy after having established the definitive histological diagnosis. The 16 patients with benign lesions were correctly diagnosed and their testicles were not removed. CONCLUSIONS: Advanced and innovative ultrasonography technology allows the detection of increasingly small testicular masses. In the present series, most incidental intratesticular lesions were benign. In patients with malignant lesions, multifocal TIN and/or distant seminomatous foci were present despite the tumour being small. Therefore, it is essential to perform exploratory surgery as it is the only way to obtain accurate histological findings, thus providing oncological efficacy and precluding removal of a testicle bearing a benign lesion.  相似文献   
996.
Microsurgery is today an established technique in specialties such as plastic surgery, neurosurgery, and trauma surgery. However, specialized training is a prerequisite for mastering anastomosis of small-diameter vessels or coaptation of nerves in the operating room. The training should be as realistic as possible and thus, laboratory animals such as the rat are preferably used as a substitute. In an attempt to minimize the use of living animals without jeopardizing a realistic training setting, we developed a pulsatile perfused porcine coronary artery model for microsurgical education. The training model consists of a membrane pump that generates a pulsatile flow within a coronary artery of a porcine heart. The pump is commercially available with a dimension of approximately 130 x 100 x 60 mm and a weight of 190 g. The pump is energized by 220 B and the motor is run on a transformed power of approximately 12 V (range, 1.5-12 V). Different fluids from simple saline solution to theoretically whole blood can be used for perfusion. The membrane pump proved to be very reliable during microvascular training because of its convenient size and wide range of feed rate providing a very realistic training setting. A maximum fluid output of 850 mL/min can be achieved. The pump has a high acceptance in microsurgical trainees evaluated by questionnaires during several microsurgical courses. The pulsatile perfused porcine coronary artery system for microsurgical training enables the trainee to work under the most realistic training settings. It proved to be a valuable tool during microsurgical education, reducing the costs and sparing living laboratory animals. Thus, we can recommend this system to anyone who is involved in training and teaching microsurgical skills.  相似文献   
997.
Akkad T  Gozzi C  Deibl M  Müller T  Pelzer AE  Pinggera GM  Bartsch G  Steiner H 《The Journal of urology》2006,175(4):1268-71; discussion 1271
PURPOSE: We analyzed the risk factors and incidence of secondary TCC of the remnant urothelium in women following radical cystectomy for TCC of the bladder. MATERIALS AND METHODS: A total of 85 women with a mean age of 64.5 years with clinically localized TCC of the bladder underwent radical cystectomy between 1992 and 2004. Orthotopic bladder substitution was performed in 46 females, while 39 underwent nonorthotopic urinary diversion. Of the entire cohort 22 (26%) patients underwent cystectomy for multifocal or recurrent TCC. Followup examinations were performed at 6-month intervals. RESULTS: Mean followup in the entire cohort was 49.8 months (median 42). Intraoperative frozen sections obtained from the urethra and distal ureters were negative for TCC and CIS in all patients. Four women (4.7%) had TCC in the remnant urothelium at a mean of 56 months postoperatively. These patients had undergone cystectomy for multifocal or recurrent TCC (4 of 22 or 18%). No secondary TCC was seen in the 63 patients with solitary invasive or nonrecurrent bladder cancer (p <0.05). Urethral recurrence was found in 2 patients (4.3%) 65 and 36 months after orthotopic neobladder surgery, respectively. In the orthotopic group 1 patient (2.1%) had an upper urinary tract tumor 76 months after surgery, while in the nonorthotopic group 1 (2.5%) was found to have an upper urinary tract tumor 48 months postoperatively. CONCLUSIONS: Recurrent or multifocal TCC may represent a risk factor for secondary TCC of the remnant urothelium after cystectomy. In our series all recurrent tumors were late recurrences (more than 36 months postoperatively). Because the rate of urethral recurrence in the current series corresponds to that reported in men (2% to 6%), urethra sparing cystectomy with orthotopic bladder replacement does not appear to compromise the oncological outcome in women.  相似文献   
998.
Gamma surgery in the treatment of nonsecretory pituitary macroadenoma   总被引:9,自引:0,他引:9  
OBJECT: The authors report on a retrospective analysis of the imaging and clinical outcomes following gamma surgery in 100 patients with nonsecretory pituitary macroadenoma. METHODS: Between June 1989 and March 2004, 100 consecutive patients with nonsecretory pituitary macroadenoma were treated at the Lars Leksell Center for Gamma Surgery, University of Virginia Health System (Charlottesville, VA). Ninety-two patients had residual or recurrent macroadenoma following one or more surgical procedures. In eight patients, gamma surgery was the primary treatment. Ten patients received conventional fractionated radiotherapy before the gamma surgery. Sixty-nine patients required hormone replacement therapy for one or more deficits before gamma knife treatment. Peripheral doses between 5 and 25 Gy (mean 18.5 Gy) were administered. Imaging and endocrinological follow-up evaluations were performed in 90 patients; these studies ranged from 6 to 142 months (mean 44.9 months) and 6 to 127 months (mean 47.9 months), respectively. Tumor volume decreased in 59 patients (65.6%), remained unchanged in 24 (26.7%), and increased in seven (7.8%). The minimal effective peripheral dose was 12 Gy; peripheral doses greater than 20 Gy did not seem to provide additional benefit. Of 61 patients with a partially or fully functioning pituitary gland and follow-up data, 12 (19.7%) suffered new hormone deficits following gamma surgery. In patients with endocrinological follow-up data that had been collected over more than 2 years, the rate of new deficits was 25%. No neurological morbidity or death was related to treatment. CONCLUSIONS: Current experience suggests that gamma surgery is an appropriate means of managing recurrent or residual nonsecretory pituitary macroadenoma following microsurgery and a primary treatment in selected patients. To evaluate definite rates of recurrence and new endocrine deficiencies, long-term follow-up studies are needed.  相似文献   
999.
1000.
Dolinskas  CA; Zimmerman  RA; Bilaniuk  LT 《Radiology》1978,126(2):409-411
Of 109 children examined by cranial computed tomography soon after an acute head injury, a density in the region of the falx was identified in 24 patients, but disappeared on subsequent studies. The density measures in the range of blood and is thought to represent subarachnoid blood. It can be confused with falx calcification in adolescents and adults, but falx calcification is normally not seen in the pediatric population.  相似文献   
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