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排序方式: 共有272条查询结果,搜索用时 15 毫秒
61.
62.
Lipid peroxidation and susceptibility of low-density lipoprotein to in vitro oxidation in hyperhomocysteinaemia 总被引:4,自引:0,他引:4
H. J. BLOM H. A. KLEINVELD† G. H. J. BOERS† P. N. M. DEMACKER† H. L. M. HAK-LEMMERS† M. T. W. B. TE POELE-POTHOFF J. M. F. TRIJBELS 《European journal of clinical investigation》1995,25(3):149-154
Abstract. The pathobiochemical mechanism of arteriosclerosis in hyperhomocysteinaemia has not yet been elucidated. In vitro studies have shown that the cytotoxic properties of homocysteine can be ascribed to its generation of reactive oxygen species. We studied lipid peroxidation, both in vivo and in vitro , in 10 homozygous cystathionine synthase-deficient (CSD) patients and in a control group of 10 healthy subjects of comparable age and sex. The susceptibility of low-density lipoprotein (LDL) from hyperhomo-cysteinaemic patients to oxidation was determined in vitro by continuously measuring the conjugated diene production induced by incubation with copper ions. Oxidation resistance (expressed as lag time), maximal oxidation rate, and extent of oxidation (expressed as total diene production) of LDL from CSD patients were not significantly different from those of LDL from controls. Furthermore, the time needed to reach maximal diene production, i.e. t(max), was similar for LDL from patients and controls. In addition, the vitamin E concentrations in LDL of CSD patients and controls were similar. The mean concentration (± SD) of plasma thiobarbituric acid reactive substances (TBARS), an indicator of in vivo lipid peroxidation, was 2.2 ± 0.7 μmol L-1 in CSD patients, a lower value than that measured in the matched controls (50± 2.0 μmol L-1 ). Investigation of in vivo and in vitro parameters of lipid peroxidation shows that the increased risk of arteriosclerosis in hyperhomocysteinaemia is unlikely to be due to increased lipid peroxidation. 相似文献
63.
Diaphragmatic rupture: CT findings in 11 patients 总被引:7,自引:0,他引:7
64.
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66.
We investigated whether cigarette smoking, measured by follicular fluid
concentrations of cotinine (a major metabolite of nicotine), affects the
maturity of oocytes from women undergoing in-vitro fertilization (IVF) and
embryo transfer. In 234 women, follicular fluid samples were assessed for
cotinine and their 2020 oocytes were assessed for maturity stage. Data on
individual proportions of oocytes which were mature (OM) and were
fertilized (OF) were analysed by regression in relation to age and
follicular fluid cotinine. OF gave an independent assessment of oocyte
maturity. Both age and follicular fluid cotinine entered the OM and OF
regressions and were significant. The age-adjusted regression coefficients
for log cotinine were positive; greater cotinine concentrations usually
accompanied greater OM and OF. The cotinine effect on OM was positive in
younger women, but it became negative (decreased OM with increasing
cotinine concentrations) in older women (> or = 40 years). We further
found in older women an average reduction of approximately 50% in the
number of mature oocytes; this reduced number was lower than the number of
embryos usually transferred. Smoking can reduce the number of mature
oocytes even further, therefore risking a negative IVF-embryo transfer
outcome. This may be the reason why the negative effects of smoking become
clinically detectable in older women.
相似文献
67.
Percutaneous abdominal biopsy: cost-identification analysis 总被引:1,自引:0,他引:1
68.
Prognostic significance of HIV-associated oral lesions and their relation to therapy 总被引:1,自引:0,他引:1
W Birnbaum TA Hodgson PA Reichart W Sherson SW Nittayannanta TE Axell 《Oral diseases》2002,8(S2):110-114
The oral manifestations of HIV infection have been considered to be of value in assessing disease progression in the developed world. However, the potential use of oral lesions as prognostic markers in resource-poor countries has yet to be fully investigated. There is reasonably compelling evidence in the developed world for an association between oral lesions and viral load. However, the true nature of this association is less clear and there are few data available from the developing world. With the introduction of HAART, a change in prevalence of the oral manifestations of HIV infection has been observed, including regression of oral candidiasis, Kaposi's sarcoma and oral hairy leukoplakia. However, oral condylomata and herpes simplex virus infection appear to persist with HMRT therapy. Further research in partnership with resource-poor countries is required to document disease progression and the associated oral lesions in both adults and children. 相似文献
69.
70.
Determination of adhesion force between single cell pairs generated by activated GpIIb-IIIa receptors 总被引:2,自引:0,他引:2
A biophysical approach was used to directly determine the avidity of the junction between two Chinese hamster ovary (CHO) cells bearing recombinant GpIIb-IIIa in the presence and absence of fibrinogen. Micromanipulation was used to induce conjugation of the cell pairs with or without activating the GpIIb-IIIa molecules with monoclonal antibody (MoAb) 62. Activation of GpIIb-IIIa caused an increase in the force required to separate the conjugates. The molecular bonding force between cells bearing activated GpIIb-IIIa and fibrinogen molecules was found to be 2.1 x 10(-7) dyne, which is 3.7 times higher than that between nonactivated GpIIb-IIIa and fibrinogen (5.7 x 10(-8) dyne). The results provide a quantitative assessment of the molecular bonding force between fibrinogen and the GpIIb-IIIa expressed on cell surface. The findings indicate that the activation of GpIIb-IIIa leads to an increase in the adhesive force in CHO cell aggregation by increasing the strength of the GpIIb-IIIa-fibrinogen bonds rather than the number of these bonds. 相似文献