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排序方式: 共有648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.
Screening for early ovarian cancer 总被引:5,自引:0,他引:5
3.
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
4.
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
5.
Direct modulatory effect of C-reactive protein on primary human monocyte adhesion to human endothelial cells 总被引:8,自引:0,他引:8
C-reactive protein (CRP) is the prototypic acute phase serum protein in humans. The effects of CRP on primary human monocyte adhesion molecule expression and interaction with the endothelium have not been studied. Herein, we describe an investigation into the phenotypic and functional consequences of CRP binding to peripheral blood monocytes ex vivo. Peripheral whole blood was collected from healthy, non-smoking males. Mononuclear cells (MNC) and monocytes were isolated by differential centrifugation using lymphoprep and Dynal negative isolation kit, respectively. Cells were exposed to CRP from 0 to 250 micro g/ml for 0-60 min at 37 degrees C and analysed for (a) CD11b, PECAM-1 (CD31) and CD32 expression by flow cytometry and (b) adhesion to LPS (1 micro g/ml; 0-24 h) treated human umbilical vein endothelial cells (HUVEC). CD14+ monocyte expression of CD11b increased significantly up to twofold when exposed to CRP, compared to controls. There was no significant difference in CD32 expression, whereas CD31 expression decreased after exposure to CRP. CRP treatment of monocytes inhibited their adhesion to early LPS-activated HUVEC (0-5 h). However, the adhesion of CRP-treated monocytes to HUVEC was significantly greater to late activation antigens on HUVEC (24 h, LPS) compared to controls. We have shown that CRP can affect monocyte activation ex vivo and induce phenotypic changes that result in an altered recruitment to endothelial cells. This study provides the first evidence for a further role for C-reactive protein in both monocyte activation and adhesion, which may be of importance during an inflammatory event. 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.
10.
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