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排序方式: 共有847条查询结果,搜索用时 31 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results   总被引:2,自引:0,他引:2  
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Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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4.
A national mail survey was performed that examined reports of recent residency graduates about hospital privileges for family physicians, perceptions of residency program directors about the percentage of their graduates who obtain privileges, and plans of third-year residents for seeking privileges. Privileges in medicine, pediatrics, surgery, obstetrics, and coronary care/intensive care units (CCU/ICU) were examined. Questionnaires were mailed to a random sample of 308 residency graduates aged 30 to 35 years, all 383 family practice residency directors, and a random sample of 319 third-year residents. Two mailings produced an 82 percent response rate. Most recent graduates had privileges in medicine (97 percent), pediatrics (95 percent), and CCU/ICU (87 percent). A majority (64 percent) had obstetric privileges, and a minority (36 percent) had surgical privileges. Directors were accurate in their perceptions of privileges attained by graduates in medicine, pediatrics, and CCU/ICU, but underestimated the percentage who had privileges in surgery and overestimated the percentage who had privileges in obstetrics. Residents planned on seeking privileges in medicine, pediatrics, and obstetrics at a rate similar to recent graduates, with lower percentages planning on seeking them in surgery and CCU/ICU. Privileges in surgery and obstetrics were more prevalent in the Midwest and West.  相似文献   
5.
Tumor vascular signals in renal masses: detection with Doppler US   总被引:3,自引:0,他引:3  
Ramos  IM; Taylor  KJ; Kier  R; Burns  PN; Snower  DP; Carter  D 《Radiology》1988,168(3):633-637
The vascularity of 49 renal masses (26 malignant and 23 benign lesions) was investigated with duplex Doppler ultrasound. Doppler signals obtained at the margins of renal masses were defined as "tumor signals" when the Doppler-shifted frequency of the lesion exceeded the frequency shift in the ipsilateral main renal artery. These exceeded 2.5 kHz with a 3-MHz insonating frequency. Among the 26 renal masses that subsequently proved to be malignant, tumor signals were obtained in 15 of 18 (83%) untreated renal cell carcinomas, in three of four Wilms tumors, and in two patients with metastases to the kidney, but not in the one patient with lymphoma. None of the 23 benign renal masses demonstrated tumor signals. Tumor vascularity in malignant lesions gives rise to abnormal, high-velocity, Doppler-shifted signals that can help in the differential diagnosis of renal masses.  相似文献   
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In human in-vitro fertilization (IVF)-embryo transfer, the in-vitro culture environment differs from in-vivo conditions in that the oxygen concentration is higher, and in such conditions the mouse embryos show a higher concentration of reactive oxygen species (ROS) in simple culture media. ROS are believed to cause damage to cell membranes and DNA fragmentation in somatic cells. This study was conducted to ascertain the level of H2O2 concentration within embryos and the morphological features of cell damage induced by H2O2. A total of 62 human oocytes and embryos (31 fragmented, 15 non-fragmented embryos, 16 unfertilized oocytes) was obtained from the IVF-embryo transfer programme. The relative intensity of H2O2 concentrations within embryos was measured using 2',7'-dichlorodihydrofluorescein diacetate by Quanti cell 500 fluorescence imaging and DNA fragmentation was observed with transmission electron microscopy and an in-situ apoptosis detection kit. The H2O2 concentrations were significantly higher in fragmented embryos (72.21 +/- 9.62, mean +/- SEM) compared to non-fragmented embryos (31.30 +/- 3.50, P < 0.05) and unfertilized oocytes (30.75 +/- 2.67, P < 0.05). Apoptosis was observed only in fragmented embryos, and was absent in non-fragmented embryos. Electron microscopic findings confirmed apoptotic bodies and cytoplasmic condensation in the fragmented blastomeres. We conclude that there is a direct relationship between increased H2O2 concentration and apoptosis, and that further studies should be undertaken to confirm these findings.   相似文献   
8.
The capacity of the peritoneal serosa to undergo metaplasia to müllerian-type epithelium is well recognized. We report a case of squamous metaplasia of the peritoneum that was studied by light microscopy. Immunohistochemical techniques, and electron microscopy. The pathogenesis of peritoneal squamous metaplasia is obscure, but may be a response to chronic irritation.  相似文献   
9.
Diagnostic value of citrate agar electrophoresis. Am J Clin Pathol 71:668-671, 1979. Of approximately three dozen hemoglobin variants that have greater than usual oxygen affinity, nearly half are inseparable from hemoglobin A by electrophoresis at pH 8.6. A comparison of hemoglobins Wood (alpha2beta297leu) and Malm? (alpha2beta297gln) is of interest from several standpoints. They represent similar substitutions at the identical locus in the beta chain. They result in identical clinical and hematologic manifestations. Oxygen affinities of these variants are identical. Both are poorly resolved from hemoglobin A by electrophoresis at pH 8.6. The position of each is identical when studied by isoelectric focusing in polyacrylamide gel. Finally, they are easily distinguished by citrate agar electrophoresis at pH 6.2. The excellent resolution of hemoglobins Malm? and Wood from each other results neither from difference in charge, nor size, nor in quaternary structure. This technic provides a simple but effective means for identifying and differentiating these hemoglobin variants. Comparison with the results of citrate agar electrophoresis of other high oxygen-affinity hemoglobins indicates that the findings for hemoglobins Malm? and Wood are unique and unambiguous.  相似文献   
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