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排序方式: 共有782条查询结果,搜索用时 0 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.
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.
C-reactive protein in population samples 总被引:5,自引:0,他引:5
The significance of C-reactive protein (CRP) was studied in three different sets of specimens. Raised levels (greater than 10 mg/l) were detected in 2.0% of 380 healthy blood donors from whom two blood specimens, taken at an interval of half a year, were tested. Except for two cases, only one of the two specimens was positive. Raised levels were found three times as frequently (in 6.6%) in a random middle-aged population sample consisting of 531 subjects. More than 40% of the raised levels could be connected to acute respiratory infections, and about 20% to smoking. Five of the 35 subjects (14%) in the population sample with elevated CRP had rheumatoid arthritis. The third set of sera comprised pre-illness specimens from 22 subjects who developed rheumatoid arthritis a few months to five years later. Although it had previously been proved that the majority of these sera contained rheumatoid factors, the CRP concentration was increased in one specimen only. 相似文献
8.
Subtyping of hepatitis B surface antigen by radioimmunoassay. 总被引:1,自引:0,他引:1
A solid-phase radioimmunoassay used for HBsAg screening of blood donors at the Finnish Red Cross Blood Transfusion Service (FRC-RIA) was modified for subtyping of HBsAg. The anti-HBs coated test tubes of FRC-RIA served as the solid-phase anti-HBs. Monospecific 125I-labelled antibodies were prepared by absorption of the labelled anti-HBs used in FRC-RIA with partially purified HBsAg coupled to Sepharose 4B.Labelled anti-y detected 4 ng/ml of ay antigen and 160 ng/ml of ad antigen; the reagent was 40 times more sensitive for the homologous subtype. Labelled anti-d detected 3 ng/ml of ad antigen, but it did not bind to ay antigen. Thus, anti-d was completely monospecific. The standard FRC-RIA was only about 5 times more sensitive than the subtype RIA; 96% of HBsAg positive blood donor samples screened by FRC-RIA could by subtyped by RIA.The important feature of this method is the absorption of the antibodies in the presence of carrier protein after radioactive labelling. This has certain advantages: (1) No extra radioactive labelling is needed for subtyping, because the labelled anti-HBs of standard RIAs for HBsAg can be utilized. (2) Small amounts of labelled monospecific antibodies can be prepared at a time, which promotes economical use of reagents. (3) Only crude antigen preparation (e.g. polyethyleneglycol precipitate from plasma) is needed for the absorption of antibodies. 相似文献
9.
High expression of nitric oxide synthases is a favorable prognostic sign in non-small cell lung carcinoma 总被引:2,自引:0,他引:2
Puhakka A Kinnula V Näpänkangas U Säily M Koistinen P Pääkkö P Soini Y 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2003,111(12):1137-1146
Immunohistochemical expression of neuronal (n), endothelial (e), and inducible (i) NOS and their association with the type, grade, apoptotic index, proliferation of tumors and the survival of patients were investigated in 89 biopsies of non-small cell lung carcinoma (NSCLC). In tumor cells, expression of iNOS was detected in 35/89 (40%) cases, while 79/89 (89%) and 72/89 (81%) cases showed weak to intense positivity for eNOS and nNOS, respectively. Strong eNOS staining was seen significantly more often in adenocarcinomas than in squamous cells carcinomas (p=0.016), and iNOS immunoreactivity was seen more often in grade I-II tumors than in grade III tumors (p=0.024). There was no significant difference between the low and high apoptotic indexes or between the low and high proliferation rates of tumors in any instance of NOS staining. The patients with tumors showing high nNOS expression tended to have better survival than the others (p=0.06, log-rank; p=0.04, Bresow; p=0.048, Tarone-Ware). Similarly, the patients with tumors showing high expression of iNOS, eNOS and nNOS, as determined by a combined sum index, had a better survival than those with a low sum index for these enzymes (p<0.05). The results show intense expression of eNOS and nNOS, and moderate expression of iNOS in tumor cells of non-small cell carcinoma. Intense NOSs expression seems to be a favorable prognostic sign in non-small cell lung carcinoma. 相似文献
10.