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21.
Recent studies have shown that antithrombin III (AT III)/heparin is capable of inhibiting the catalytic activity of factor VIIa bound either to relipidated tissue factor (TF) in suspension or to TF expressed on cell surfaces. We report studies of the mechanism of which by AT III inhibits factor VIIa bound to cell surface TF and compare this inhibitory mechanism with that of tissue factor pathway inhibitor (TFPI)-induced inhibition of factor VIIa/TF. AT III alone and AT III/heparin to a greater extent reduced factor VIIa bound to cell surface TF. Our data show that the decrease in the amount of factor VIIa associated with cell surface TF in the presence of AT III was the result of (1) accelerated dissociation of factor VIIa from cell surface TF after the binding of AT III to factor VIIa/TF complexes and (2) the inability of the resultant free factor VIIa-AT III complexes to bind effectively to a new cell surface TF site. Binding of TFPI/factor Xa to cell surface factor VIIa/TF complexes markedly decreased the dissociation of factor VIIa from the resultant quaternary complex of factor VIIa/TF/TFPI/factor Xa. Addition of high concentrations of factor VIIa could reverse the AT III-induced inhibition of cell surface factor VIIa/TF activity but not TFPI/factor Xa-induced inhibition of factor VIIa/TF activity. 相似文献
22.
Background
To determine differences among persons who provided blood specimens for HIV testing compared with those who did not among those interviewed for the population-based Zimbabwe Young Adult Survey (YAS). 相似文献23.
We measured total respiratory system compliance (Crs) before and after instilling 25 mg artificial surfactant in 1 ml saline down the endotracheal tube of preterm babies requiring resuscitation at birth, and compared results with data from 6 similar babies receiving saline only. Surfactant did not produce a significant improvement in Crs. 相似文献
24.
Sparks DL Connor DJ Browne P Sabbagh MN;AD Cholesterol-Lowering Treatment Trial Team 《Journal of molecular neuroscience : MN》2002,19(1-2):209-212
Elevated circulating cholesterol can have profound effects on the health of an individual. Such excess cholesterol can promote
coronary artery disease, production and accumulation of β-amyloid in the brain, and possibly Alzheimer’s disease (AD). In
a clinical trial evaluating the benefit of a cholesterol-lowering drug in the treatment of AD, mean cholesterol levels at
baseline among individuals participating in the trial were found to be relatively high. Based on this observation we suggest
that cholesterol levels should be actively monitored in the elderly, as many individuals with AD are over 65 years of age
and therefore excluded by currently accepted guidelines. 相似文献
25.
SE Daley AD Pearson AW Craft J Kernahan RA Wyllie L Price C Brock C Hetherington D Halliday K Bartlett 《Archives of disease in childhood》1996,75(4):273-281
Whole body protein synthesis and catabolism were measured using the [ring-2H5]phenylalanine and [1-13C]leucine primed constant infusion technique in 32 paediatric patients with cancer at different stages of treatment. Rates of synthesis (S) and catabolism (C) derived from the [ring-2H5]phenylalanine and [1-13C]leucine models were 4.7 (SD 1.3) (S) and 6.0 (1.5) (C) g/d/kg, and 5.5 (0.8) (S) and 6.8 (1.2) (C) g/d/kg, respectively. These results show that these two tracer techniques give similar results in this study population. Comparison of these values with results previously reported for groups of control children using the [ring-2H5]phenylalanine model (S = 3.69 and 3.93; C = 4.09 and 4.28 g/d/kg) and the [1-13C]leucine model (S = 4.32; C = 4.85 g/d/kg) show that rates of synthesis and catabolism were higher in cancer patients than in controls. Thus whole body protein turnover is increased in children under treatment for cancer. Other indices of metabolism such as plasma amino acids and intermediary metabolites were also measured and showed that, although subjects were in isotopic steady state, there were significant metabolic changes during the course of the primed constant infusions used to measure protein turnover. 相似文献
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Between June 1986 and April 1988, 86 sonographic examinations of the shoulder were performed on patients suspected of having rotator cuff tears. Major sonographic diagnostic criteria included (a) a well-defined discontinuity usually visible as a hypoechoic focus within the cuff, (b) nonvisualization of the cuff and (c) an echogenic focus within the cuff. Seventy-five patients underwent both sonography and arthrography. Compared with arthrography alone, ultrasound examinations enabled detection of 92% of rotator cuff tears (24 of 26 tears), with a specificity of 84% and a negative predictive value of 95%. Correlation was obtained in 30 of these patients who underwent surgery for rotator cuff tear or other soft-tissue abnormality. In this group, the sensitivity of sonography for detection of a tear was 93%, with a specificity of 73%, while for arthrography sensitivity was 87% and specificity was 100%. These data indicate that sonography is a useful, noninvasive screening procedure for patients suspected of having rotator cuff injury. 相似文献
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Mammary intraepithelial neoplasia outgrowths (MINO): MINO and human ductal carcinoma <Emphasis Type="Italic">in situ</Emphasis> 总被引:1,自引:0,他引:1
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Germ-line mutations in the BRCA1 tumour suppressor gene contribute to familial breast tumour formation, but there is no evidence for direct mutation of the BRCA1 gene in the sporadic form of the disease. In contrast, decreased expression of the BRCA1 gene has been shown to be common in sporadic tumours, and the magnitude of the decrease correlates with disease progression. BRCA1 expression is also tightly regulated during normal breast development. Determining how these developmental regulators of BRCA1 expression are co-opted during breast tumourigenesis could lead to a better understanding of sporadic breast cancer aetiology and the generation of novel therapeutic strategies aimed at preventing sporadic breast tumour progression. 相似文献