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91.
Sonography detected a paraaortic pulsatile tubular mass in a patient 10 years after “stump” nephrectomy, which was subsequently confirmed as a renal artery-renal vein fistula by computed tomography, angiography, and laparotomy.  相似文献   
92.
A boy aged 4.5 years with prune-belly syndrome (PBS) and associated urethral stenosis, oligohydramnios, imperforate anus and vesicosigmoid fustula is described. In contrast to the anticipated poor prognosis, vesicostomy and divided transverse colostomy performed after birth followed by prophylaxis of infection and bicarbonate supplementation have resulted in a good outcome. The vesicosigmoid fistula might have served in utero as a natural diversion protecting from pressure-induced renal damage. It is suggested that the main determinant of prognosis in PBS is the presence and degree of kidney dysplasia at birth as reflected by the neonatal renal function after performance of an indicated urinary diversion procedure rather than the presence of severe associated anomalies.Supported in part by grants from the National Institute of Health AM 37223-01 and the Medical School and Graduate School Research Committees of the University of Wisconsin and a Research Career Development Award KO4 AM 00421 (RWC), by the Pearl M. Stetler Foundation (SD) and by a National Kidney Foundation fellowship (IZ)  相似文献   
93.
Epidermal growth factor receptor (EGFR), determined by the Scatchard curve method, was found in 22 cases of a random series of 100 patients with breast carcinoma. Two groups of patients were identified, one (n = 16) with a low concentration (0–50 fm/mg protein) of EGFR but with a high affinity (Kd = 3.2 nM), and the other (n = 6) with a high concentration (90–210 fm/mg protein) of EGFR but with a lower affinity (Kd = 6.3 nM).A significant inverse relationship was found between the presence of EGFR and receptors for estrogen (p<0.001) and progesterone (p = 0.001). EGFR was found in no (0/8) tumors with Grade I histoprognostic grade, 17% (10/58) Grade II, and 38% (11/29) Grade III (p<0.05). EGFR is present therefore in poorly differentiated tumors and associated with other factors of poor prognosis. Ourin vivo analyses confirm results found in tissue culture derived from human breast carcinoma cells.With the technical assistance of J. Barraque.  相似文献   
94.
D-54 MG, a human glioma-derived continuous cell line growing as subcutaneous or intracranial xenografts in athymic mice, was found to be sensitive to the effects of D,L-buthionine-(SR)-sulfoximine, a selective inhibitor of gamma-glutamylcysteine synthetase. Intraperitoneal administration of one dose of buthionine sulfoximine (BSO, 5 mmol/kg) resulted in depletion of total intracellular glutathione to 57 and 47% of control 12 hr, and 73 and 23% of control 24 hr, after BSO in subcutaneous and intracranial xenografts respectively. Concurrent measurement of total glutathione in the contralateral (non-tumor-containing) cerebral hemisphere in mice bearing intracranial D-54 xenografts demonstrated insignificant depletion of glutathione. Multiple doses of BSO, at 12-hr intervals, resulted in further depletion to 27% (s.c.) and 16.5% (i.c.) of control 12 hr following the final dose of BSO. Quantitative analysis of BSO delivery to xenograft and contralateral brain tissue revealed transfer constants, K1, of 15.8-24.1 x 10(-3) and 2.4 x 10(-3) ml.g-1.min-1 for xenograft and "normal" brain respectively. This highly selective depletion of glutathione in neoplastic tissue versus surrounding non-neoplastic host tissue may have therapeutic implications for the rational use of chemotherapeutic and radiotherapeutic intervention.  相似文献   
95.
96.
Summary The ganglioside patterns of medulloblastomas have never been established; in this study we report the ganglioside profile of the human medulloblastoma cell line TE-671 grown as a xenograft in nude mice. Gangliosides were isolated and structurally analyzed by fast atom bombardment mass spectometry following permethylation. Identification of individual gangliosides was also performed by immunostaining of high-performance thin-layer chromatography-separated bands. Total ganglioside levels of 0.20 mol/g of tissue were obtained, consistent with those reported for human glioma cell lines grown as xenografts; predominant monosialogangliosides of TE-671 xenografts were II3--NeuAc-LacCer (GM3) and II3--NeuAc-GgOse3 Cer (GM2) but there were also relatively large proportions of IV3--NeuAc-LcOse4Cer (3-isoLM1), IV3--NeuAc-nLcOse4Cer (3-LM1) and a further ganglioside of the neolactoseries with an extra lactosamine moiety. The only oligosialoganglioside detected was IV3, II3--NeuAc2-GgOse4Cer (GD1a).Abbreviations: The gangliosides have been designated according to Svenerholm [18] GM3 II3--NeuAc-LacCer - GM2 II3--NeuAc-GgOse3Cer - GM1 II3--NeuAc-GgOse4Cer - 3-LM1 IV3--NeuAc-nLcOse4Cer - 3-isoLMI IV3--NeuAc-LcOse4Cer - Fuc-3-isoLMI IV3--NeuAc, III4-Fuc-LcOse4Cer - GD1a IV3, II3--NeuAc2-GgOse4Cer - FAB-MS Fast atom bombardment-mass spectometry - GC-MS gas chromatography-mass spectometry Supported by NC1 RO1 CA11898 to Dr. Bigner and B8803X-00627-24B from the Swedish Medical Research Council to Dr. L. Svennerholm  相似文献   
97.
98.
The clinical and pathological features of 33 previously untreated patients with primary breast sarcoma were retrospectively analysed to evaluate the prognostic significance of histologic variables on survival. The series comprised 17 cystosarcomas phyllodes and 16 stromal sarcomas (excluding angiosarcomas).All tumors were reviewed and classified in similar fashion to extramammary soft tissue sarcomas. In addition, immunohistochemical studies were performed on paraffin sections with a panel of several antibodies directed against cytoskeletal filaments and cellular enzymes; five cases were also examined by electron microscopy.Most tumors were malignant fibrous histiocytoma (21 cases) and fibrosarcoma (6 cases) types. Surgery was the main therapy. Metastasis-free survival rate was significantly correlated only with histological grade, consisting of tumor differentiation, tumor necrosis, and mitotic activity. Courses and survivals of the cystosarcoma and stromal groups were identical, questioning the clinical value of this pathologic distinction. All local recurrence, metastasis, or death occurred within 30 months, though follow-up was much longer.Immunohistochemistry was disappointing for identification of specific histologic sub-types.  相似文献   
99.
PURPOSE: To document the current state of institutional review board (IRB) and conflict of interest committee policies regarding disclosures of financial conflicts of interest to potential research participants, and to use this information to identify and share models for effectively achieving disclosure. METHOD: The authors identified the 123 U.S. academic medical centers that have IRBs and sought their IRB and institutional policies regarding financial conflicts of interest. In February and March 2004, using manual and key word searches, each institution's Web site was searched to identify documents containing information regarding the disclosure of financial conflicts of interest. Letters were sent to 24 institutions that had either no information or incomplete information posted on their Web sites. To assess institutions' guidelines for disclosure, the authors extracted and content coded each institution's information on disclosure. RESULTS: Relevant information was obtained from 120 (98%) academic medical centers (AMCs), of which 57 (48%) mentioned disclosing financial conflicts to potential research participants. Of these 57, 33 (58%) included verbatim language that could be used in informed consent documents. AMCs' recommendations and requirements for disclosure included details of the financial arrangement, administrative management of conflicts of interest, and encouragement of dialogue between the investigator and the potential research participant. CONCLUSIONS: Considerable variability exists concerning the specific information that should be disclosed. Most of the AMCs' policies were consistent with the goal of protection from legal liability. Significant questions remain, however, concerning the goals of disclosure and the most effective methods for achieving those goals.  相似文献   
100.
Carriage of nuclear dehydrogenating clostridia has been associated with colon cancer and implicated in its aetiology. This study has compared the carriage of these organisms in a British population at high risk for the development of colon cancer with a low risk Nigerian population. Clostridia were found in all of the stools from both populations. Nuclear dehydrogenating clostridia were only found in the stools of the British subjects (32%). These results support the suggestion that the carriage rate of nuclear dehydrogenating clostridia in a population is related to the risk of colon cancer.  相似文献   
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