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Purpose

We evaluated the safety and efficacy of percutaneous testis biopsy by comparing the ultrasound appearance and histological status of testicular parenchyma obtained to those noted after open testis biopsy.

Materials and Methods

A total of 51 consecutive infertile men with azoospermia or severely impaired semen quality, in whom ductal obstruction was suspected, underwent percutaneous (31) or open (20) testis biopsy, with 58 and 34 procedures performed, respectively. Scrotal ultrasound was performed preoperatively, and at 2 weeks and 1, 3 and 6 months after biopsy. In addition, immunoglobulins G and A antisperm antibody assays were obtained preoperatively and postoperatively. Two biopsy specimens were obtained from each testis for formal histological evaluation. A touch preparation was also performed and examined immediately for mature spermatozoa using phase contrast microscopy.

Results

All biopsies yielded adequate tissue for diagnosis and morphometric analysis. Of 58 percutaneous biopsies 4 (7 percent) demonstrated sonographic evidence of intratesticular bleeding, characterized by a hypoechoic region within the testicular parenchyma, which resolved by 6 months postoperatively. In contrast, 10 of 34 open biopsies (29 percent) showed evidence of intratesticular bleeding or a new area of increased echogenicity at 1 month after the procedure (intraparenchymatous scar). All intraparenchymatous scars persisted to 6 months postoperatively. No patient undergoing percutaneous or open testis biopsy had antisperm antibodies in the seminal fluid or serum (azoospermia cases) or on sperm postoperatively. Of the 32 and 20 patients undergoing percutaneous and open testis biopsy 3 (9 percent) and 14 (70 percent), respectively, required narcotic analgesia. All patients returned to routine activities within 24 hours after percutaneous testis biopsy. No postoperative infections or extratesticular hematomas were noted. Pathological study was diagnostic in all specimens.

Conclusions

Percutaneous testis biopsy is well tolerated by the patient, with fewer apparent complications than and diagnostic value equal to open testis biopsy. Percutaneous testis biopsy should be considered an alternative to open biopsy.  相似文献   
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The influence on the structure-activity relationships (S.A.R.) of the stereochemistry and various alkyl, aryl, aralkyl and heterocyclic substituents at the two chiral centres in the dipeptide side-chain of a new series of penicillins was examined. In many cases the effects of these changes had a pronounced influence on the degree of activity against Gram-positive and especially Gram-negative bacteria. Several compounds indicated that the size, shape and spatial disposition of a substituent were the parameters of importance in influencing activity, rather than it lipophilic or electronic character. The most active homologues in the series provided broad-spectrum penicillins which in terms of their in vitro antibacterial properties showed improvements over certain of the marketed penicillins. Thus 6-[D-alpha(alpha'-ureidoacyl-amino)acylamino]penicillanic acids were found which had a carbenicillin-like profile, with improvements against Pseudomonas aeruginosa, Klebsiella aerogenes, sensitive and beta-lactamase-producing Gram-positive cocci.  相似文献   
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A program has been developed in Boston to bring together hospital and industrial biomedical engineers, BMETs, CEs, nurses, physicians, the Massachusetts Medical Devices Society, academic engineering technologists, and students. This program is headquartered at the Center for Clinical Engineering at the Wentworth Institute of Technology, and is designed to serve and support the interests of the participants for educational, professional, networking and interdisciplinary activities. Because of the availability of engineering technology programs at Wentworth, and the willingness of local professionals to participate, a comprehensive and unique program has been developed to train BMETs and CEs. This program emphasizes hands-on electronic technology, biomedical lectures and laboratories, management lectures and in-hospital preceptorships under the supervision of BMETs, CEs, biomedical directors and nurses.  相似文献   
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Presented in this article are aggregate utilization and financial data from the four social health maintenance organization (S/HMO) demonstrations that were collected and analyzed as a part of the national evaluation of the S/HMO demonstration project conducted for the Health Care Financing Administration. The S/HMOs, in offering a $6,500 to $12,000 chronic care benefit in addition to the basic HMO benefit package, had higher start up costs and financial losses over the first 5 years than expected, and controlling costs continues to be a challenge to the sites and their sponsors.  相似文献   
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