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71.
In India, interviews were conducted with 250 couples who had at least 2 living children and at least 1 son so researchers could examine the effect of child loss on contraceptive usage. The interviewees lived in the area served by the rural health center in Pohir. 67 couples had lost a child. The child loss group had an acceptance rate for contraception of 41.7% compared to 44.8% for the group who had not experienced child loss. The difference was insignificant. Caste, literacy, and parity did not affect contraceptive usage. These findings suggest that child loss does not play a crucial role in contraception acceptance. On the other hand, some studies show that it is a barrier to fertility limitation. Additional studies are needed to resolve the issue of child loss and fertility.  相似文献   
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A rapid and sensitive indirect enzyme-linked immunosorbent assay(ELISA) was developed for micrsomal epoxide hydrolase of ratliver. The assay, which is easily and readily performed, issignificantly more sensitive than most enzymatic epoxide hydrolaseassays routinely used and electroimmunoassays previously developed.The limit of sensitivity of the ELISA is between 2–5 ngof microsomal epoxide hydrolase. Using the ELISA microsomalepoxide hydrolases of mouse and rat liver were shown to be antigenicallyvery similar, while microsomal epoxide hydrolases of guineapig, monkey and human liver are antigenically distinct fromthose of rat and mouse. The ELISA developed here is capableof detecting microsomal epoxide hydrolase of rat and mouse livereven when significant enzymatic activity is lost. These resultsindicate that the antigenic sites recognized by the antibodiesused are distinct from the catalytic site of the epoxide hydrolase.Approximately 1.9% of rat microsomal protein was quantifiedas microsomal epoxide hydrolase by the ELISA. Low levels ofmicrosomal epoxide hydrolase were also detected in rat livercytosol (0.02% of the cytosolic protein) demonstrating thatmicrosomal epoxide hydrolase is not totally membrane bound orthat an immunologically related protein occurs in the cytosolof normal rat liver. The ELISA developed here will be valuablein investigating further the role of microsomal epoxide hydrolase.  相似文献   
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For steroid hormone function to occur, nuclear receptors interact with a series of coactivators including steroid receptor coactivator-1 (SRC-1). The SRC-1 binds the vitamin D receptor (VDR) in the presence of ligand in an activation function 2 (AF-2)-dependent manner. In order to understand the role of this interaction in 1,25-dihydroxyvitamin D3 [1,25(OH)2D3]-mediated gene expression, the level of SRC-1 expression was altered in MG-63 cells. Previous studies had demonstrated that MG-63 cells express the VDR and that 1,25(OH)2D3 regulates expression of alkaline phosphatase (ALP). Analysis of MG-63 cells demonstrated that SRC-1 is expressed. A full-length cDNA coding for SRC-1 was inserted in antisense orientation into an expression vector (anti-SRC-1). The MG-63 cells were transfected with anti-SRC-1 or mock vector and stable transformants were selected. Western blot analysis showed a 95% reduction in SRC-1 protein as compared with mock cells. We determined the effect of normal and reduced SRC-1 expression in MG-63 cells on 1,25(OH)2D3-mediated stimulation of ALP. Whereas 10−8 M 1,25(OH)2D3 produced a 3.6-fold stimulation in ALP in mock cells expressing normal levels of SRC-1, it did not alter ALP in cells expressing reduced levels of SRC-1. Thus, SRC-1 is required for 1,25(OH)2D3-mediated gene expression of ALP by human MG-63 cells. Received: 7 June 1999 / Accepted: 2 November 1999  相似文献   
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Pheochromocytoma coexisting with renal artery lesions   总被引:2,自引:0,他引:2  
PURPOSE: Physiologically significant renal artery lesions in the presence of a pheochromocytoma comprise a confounding factor which may impact on the hypertension cure following excision of the pheochromocytoma. We present 10 cases of these dual lesions and review the literature on this entity. MATERIALS AND METHODS: From 1952 to 1999, 269 patients were diagnosed with pheochromocytoma at our institution. Hospital charts of these patients were reviewed retrospectively to identify those with coexisting renal artery stenosis. A Medline search was performed to review the available literature. RESULTS: Of the 269 patients with pheochromocytoma 10 (3. 7%) had coexisting renal artery lesions, including renal artery stenosis in 8, renal artery aneurysm in 1 and postangiographic dissection occlusion in 1. Pheochromocytoma was adrenal in 8 cases and ectopic in 2. Of the patients 9 have been treated to date by adrenalectomy in 4, nephroadrenalectomy in 3, adrenalectomy plus lysis of renal artery adhesions in 1 and adrenalectomy plus renal autotransplantation with bench repair in 1. Both lesions were diagnosed preoperatively in 9 cases and a hypovascular adrenal lesion was missed preoperatively in 1. A review of literature revealed a total of 87 cases of coexisting pheochromocytoma and renal artery lesions. CONCLUSIONS: There are multiple mechanisms that can lead to renal artery stenosis and pheochromocytoma. A high index of suspicion is necessary to enable both entities to be diagnosed preoperatively and allow proper planning of surgical therapy. Incomplete diagnosis may lead to persistent hypertension postoperatively.  相似文献   
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PURPOSE: The aim of this study is to report the initial experience with needlescopic surgery (2-mm optics and instrumentation exclusively) for the cryptorchid testicle. METHODS: Ten patients (age 8 months to 37 years) underwent 12 needlescopic procedures: orchiopexy (n = 8), orchiectomy (n = 2), and diagnostic exploration with attempted excision of testicular remnant (n = 2). Two patients underwent bilateral needlescopic orchiopexy. Needlescopic (2 mm) optics and instrumentation were used exclusively in the pediatric patients. RESULTS: All procedures were completed successfully by needlescopic techniques. Mean surgical time was 110 minutes (range, 60 to 180 minutes), and blood loss was 6 mL (range, 0 to 20 mL). There were no intraoperative complications. All procedures were performed on an outpatient basis. In all 8 orchidopexies, the testis was successfully brought to a scrotal position. CONCLUSIONS: Needlescopic techniques allow safe performance of various procedures for a cryptorchid testicle. The cosmetic result is excellent.  相似文献   
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BACKGROUND: Assessment of axillary lymph node status is necessary for patients with invasive breast cancer. Sentinel node biopsy is a new minimally invasive technique that may provide accurate assessment of regional lymph node status while limiting the morbidity associated with axillary clearance. METHODS: A workshop conducted in Adelaide in November 1998 aimed to assess current sentinel node mapping and biopsy techniques, and make recommendations regarding its application in the surgical management of early breast cancer in Australia and New Zealand. RESULTS: At the conclusion of the workshop, a consensus was reached regarding indications, exclusions, sentinel node mapping/biopsy technique, nuclear medicine requirements, pathology and safety of sentinel node biopsy in breast cancer. It was agreed that a feasibility study according to an agreed prospective protocol was necessary to validate the technique by breast surgeons. Surgeons that satisfied validation criteria for the feasibility study could then consider a prospective randomized study comparing sentinel node biopsy with standard axillary dissection. CONCLUSIONS: Sentinel node biopsy in breast cancer involves close cooperation between members of a multidisciplinary team including surgeons, nuclear physicians, pathologists and radiologists. Although the technique has the potential to reduce morbidity associated with axillary surgery, surgical performance in this area will need to be closely monitored to ensure that the technique does not fall into disrepute by adversely affecting breast cancer prognosis.  相似文献   
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