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This study aimed to determine whether a weight-adjusted dose of subcutaneous enoxaparin is as effective and safe as oral acenocoumarol for the secondary prophylaxis of pulmonary embolism. Three hundred and eighty consecutive noncancer outpatients hospitalized with an episode of symptomatic pulmonary embolism selected treatment with acenocoumarol or enoxaparin at a dose of 1 mg/kg once daily after being informed of the type of administration and expected frequency of laboratory monitoring for both medicinal products. Endpoints were symptomatic recurrent thromboembolic events evaluated by standard objective testing, and a composite endpoint of recurrent venous thromboembolism, major bleeding, and death from any cause. One hundred and ninety-nine patients (52%) chose acenocoumarol therapy and 181 chose enoxaparin monotherapy. Four patients in the enoxaparin group (2.2%) and six patients in the acenocoumarol group (3%) had an objective thromboembolic recurrence (hazard ratio, 1.35; 95% confidence interval, 0.38-4.79; P = 0.64). Nine patients in the enoxaparin group (5.0%) had a hemorrhagic complication compared with 11 in the acenocoumarol group (5.5%) (P = 0.81). The hospital length of stay was shorter with enoxaparin compared with acenocoumarol (11 versus 16 days, P = 0.0001). Enoxaparin is as effective and safe as acenocoumarol in the secondary prevention of recurrent thromboembolic disease and is associated with shorter hospitalization.  相似文献   
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Chronic morphine treatment produced increases in [3H]-flunitrazepam binding in some hippocampal areas of the rat brain. The differences in binding were statistically significant in some cases. Both morphine-dependent and morphine-deprived (abstinence syndrome) animals showed an identical response in binding, which confirms a real, although small, increase in benzodiazepine binding sites in the hippocampus after morphine treatment, that is not affected by a naloxone-induced abstinence syndrome under the conditions studied. These findings support the hypothesis of a morphine-induced up-regulation of benzodiazepine binding sites in the hippocampus. A possible different response in benzodiazepine binding sites 1 and 2 could explain the different findings reported in the literature. Our data suggest that the detected increase in benzodiazepine binding would be mainly due to type 2 binding sites, since the hippocampus has a higher density of this type of benzodiazepine binding sites.  相似文献   
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We studied the plasminogen activation system in tumor tissue by measuring the antigen level of the 2 plasminogen activators, tissue-type (t-PA) and urokinase-type (U-PA) and their inhibitors, plasminogen-activator inhibitors type-1 (PAI-1) and type-2 (PAI-2) in the tissue extracts of 43 human benign and malignant ovarian tumors. U-PA levels were significantly higher in malignant than in benign tumors. In addition, U-PA antigen levels were higher in the metastatic tissue of advanced disease (FIGO stage III) than in the primary localized tumor (FIGO stage I/II). Also PAI-1 concentrations tended to be higher in malignant than in benign tumors, but this difference was not statistically significant. In contrast, t-PA levels were lower in metastatic than in non-metastatic tumors, whereas PAI-2 levels were unrelated to the stage of ovarian malignancy. These results were integrated in a plasminogen-activation-dependent malignancy index (U-PA × PAI-1/t-PA). This index distinguished the different groups of benign ovarian tumors, localized and metastatic ovarian carcinomas better than U-PA levels. It could be useful as a prognostic indicator in ovarian cancer © 1993 Wiley-Liss, Inc.  相似文献   
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An immunotoxin containing the B-B10 MoAb, directed against the CD25 determinant, and the ribosome-inactivating protein saporin, inhibits 3H-TdR incorporation in phytohemagglutin, allogeneic-stimulated lymphocytes (primary and secondary mixed-lymphocyte reaction), and in an alloreactive T cell clone. A lower degree of inhibition was obtained with the B-B10 MoAb, which is known to inhibit IL-2 activity, as well as with the unconjugated compounds. These results suggest that the in vivo administration of the conjugate might be a more effective tool in the treatment of patients affected by graft-versus-host disease than B-B10 alone, by inducing an efficient killing of allogeneic-reacting T lymphocytes.  相似文献   
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A direct in vitro tissue culture method is described for the quantitation of bovine leukemia virus, utlizing a feline S+L-- cell line.  相似文献   
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The association between the concentration of different plasma lipoproteins and plasma factor VII (F VII) was analysed by isolating plasma very low density lipoprotein (VLDL), low density lipoprotein (LDL), and high density lipoprotein (HDL) lipoproteins and assessing their in vitro interaction with F VII by immunoenzyme assay using peroxidase labelled anti-factor VII immunoglobulins to determine whether F VII coagulant activity is prognostic for cardiovascular mortality. F VII bound to triglyceride rich lipoproteins, the fixation being stronger on chylomicrons and VLDL fractions than on LDL fractions. In our experiments HDL did not bind to F VII. The fixation of coagulation factor X (FX) tested by the same method is comparable with that of F VII. The nature of this fixation seemed to arise from hydrophobic interaction as calcium was not necessary and the use of Tween 20 inhibited the interaction. The binding of factors VII and X was increased when lipids were previously treated by phospholipase C and the interaction seemed to be completely dependent on the lipid part of the lipoproteins. Hyrophobic fixation is a possible mechanism of interaction of plasma lipoproteins and F VII and X, and it may be of importance in the covariance of triglyceride concentrations and the activity of vitamin K dependent coagulation factors.  相似文献   
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Streptococcus pneumoniae is the major cause of bacterial meningitis. We report a case of meningitis due to a mixed infection with two distinct strains of S. pneumoniae: one penicillin-resistant strain of serotype 9V and one penicillin-susceptible strain of serotype 7. The two strains exhibited different pulsed-field gel electrophoresis profiles.  相似文献   
10.
Comparing bacterial genomes through conservation profiles   总被引:1,自引:1,他引:1       下载免费PDF全文
We constructed two-dimensional representations of profiles of gene conservation across different genomes using the genome of Escherichia coli as a model. These profiles permit both the visualization at the genome level of different traits in the organism studied and, at the same time, reveal features related to the genomes analyzed (such as defective genomes or genomes that lack a particular system). Conserved genes are not uniformly distributed along the E. coli genome but tend to cluster together. The study of gene distribution patterns across genomes is important for the understanding of how sets of genes seem to be dependent on each other, probably having some functional link. This provides additional evidence that can be used for the elucidation of the function of unannotated genes. Clustering these patterns produces families of genes which can be arranged in a hierarchy of closeness. In this way, functions can be defined at different levels of generality depending on the level of the hierarchy that is studied. The combined study of conservation and phenotypic traits opens up the possibility of defining phenotype/genotype associations, and ultimately inferring the gene or genes responsible for a particular trait.  相似文献   
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