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排序方式: 共有516条查询结果,搜索用时 15 毫秒
1.
Sonoelasticity imaging of prostate cancer: in vitro results 总被引:2,自引:0,他引:2
2.
This article reports the experience of a 15-person primary care group with two health maintenance organization/independent practice association (HMO/IPA) contracts. In 1986 the group received over $1.5 million in capitated payments from the plan to cover medical care of approximately 4,000 patients. The expenses exceeded the income for one plan. Analysis of primary care, specialty care, and ancillary services provides insight into factors that must be considered in evaluating HMO/IPA contracts. Eleven questions that should be asked before signing contracts and guidelines for utilization review and quality assurance are reviewed. 相似文献
3.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
4.
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
5.
Detection of reactive oxygen species (ROS) and apoptosis in human fragmented embryos 总被引:8,自引:2,他引:8
Yang HW; Hwang KJ; Kwon HC; Kim HS; Choi KW; Oh KS 《Human reproduction (Oxford, England)》1998,13(4):998-1002
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
6.
7.
Pathways to care for alcohol use disorders 总被引:1,自引:0,他引:1
8.
9.
A Hodgkin cell-specific antigen is expressed on a subset of auto- and alloactivated T (helper) lymphoblasts 总被引:21,自引:0,他引:21
A Hodgkin cell-specific antigen detected by the monoclonal antibody Ki- 1 was found on T helper lymphocytes after activation by autologous and allogeneic stimulator cells. About 50% of lymphoblasts generated by auto- and alloactivation reacted with the antibody. In contrast, only less than 6% of lymphoblasts stimulated with Con-A, phytohemagglutinin (PHA), or protein A, and none of lymphoblasts activated by oxidative mitogenesis, expressed this antigen. Among several permanent cell lines tested, the K562, MOLT-4, HL-60, and EBV transformed B lymphoblastoid cells reacted with the Ki-1 antibody. The results may indicate possible relationships between the autoreactive subset of T lymphocytes and the pathogenesis of Hodgkin's disease. 相似文献
10.
We investigated effects of hypertension and early development on myocardial energy metabolism as reflected by maximal enzyme activities, glucose transporter content, and endogenous substrates in female Wistar-Kyoto (WKY) rats and spontaneously hypertensive rats (SHR). Left ventricular hypertrophy and systolic hypertension were evident in SHR at 6 weeks of age and these differences increased at 14 and 22 weeks of age. 3-Hydroxyacyl-CoA dehydrogenase (HOAD) activity in the left ventricle was 18% lower in 6-week-old rats than both 14- and 22-week-old rats, but not different between WKY rats and SHR. Hexokinase activity was 15% lower in 6-week-old SHR than WKY rats and decreased progressively with age in both strains. Glucose transporter (GLUT) 1 content was nearly twofold greater in 6-week-old rats than both 14- and 22-week-old rats. We found no difference in citrate synthase activity or GLUT4 content among groups. Glycogen concentration was 44% lower in SHR than WKY rats, whereas triglyceride was slightly (16%) higher in SHR than WKY rats. Older animals had higher levels both glycogen and triglyceride than younger animals. We conclude that the left ventricle of both SHR and WKY rats may change from predominantly glucose to fatty acid oxidation for energy production during early development. 相似文献