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61.
62.
In order to investigate the stability of testosterone (T) and androstenedione (Adione) in blood and plasma samples following study was undertaken. 1. Pooled blood samples were left unseparated at room temperature for varying time periods of up to 3 days before being centrifuged. Subsequent plasma T and Adione values measured by radioimmunoassay showed only small, insignificant variations. 2. Plasma, initially separated from the pooled blood sample, was left at room temperature for up to 24 h. There was no significant change in the levels of T and Adione measured over this period. There was also good correlation between steroid concentrations measured in blood and plasma. 3. T and Adione were measured in a pooled plasma sample after repeated freezing and thawing of the sample. All T values were well within the intraassay coefficient of variation; all Adione values were within the precision limits of the assay, although there was a considerable spread in individual values. It is concluded that the various handling procedures of blood or plasma have no significant effect on T and Adione levels.  相似文献   
63.
Two brush border peptidases have been isolated from the particulate fraction of the rat intestinal mucosa and purified to homogeneity as judged by polyacrylamide gel electrophoresis, starch gel electrophoresis, isoelectric focusing, and double immunodiffusion. For convenience, the peptidases have been designated peptidase F (fast) and S (slow) on the basis of their anodic mobilities. The isoelectric point of peptidase F was 4.76 and of peptidase S, 5.10. Both enzymes are glycoproteins. The amino acid compositions of the two peptidases are similar. The same carbohydrates are found in both enzymes, but there are differences in the molar concentrations of individual sugars. Peptidase S has greater concentrations of mannose and galactose and of hexosamines than peptidase F, while sialic acid is slightly greater in peptidase F. Carbohydrate accounted for approximately 19% and 23% of the weight of peptidases F and S, respectively. Estimates of the molecular weights of both enzymes by gel filtration gave values of 280,000. Electrophoresis of the enzymes under denaturing conditions on sodium dodecyl sulfate polyacrylamide gels indicated that each enzyme is a dimer consisting of two subunits of equal molecular weight, 140,000.  相似文献   
64.
Peripheral blood basophils from normal human subjects responded chemotactically to the complement component C5a and also to the supernatant fluid from cultured human lymphocytes stimulated by mitogens or specific antigen. Basophil chemotactic factor (BCF) was detected in stimulated lymphocyte cultures within 24 hr and increased for the first 3 days. BCF was found after stimulation of lymphocytes by B or T cell mitogens as well as by specific antigen. The amount of BCF in culture fluids was independent of cell proliferation. Monocyte chemotactic factor (MCF) and BCF could not be separated from one another by Sephadex or DEAE chromatography. Both activities were eluted from Sephadex G-100 columns in a m.w. region of about 15,000 daltons and were found after ion exchange chromatography on DEAE in a peak eluted by 0.1 M NaCl. These findings suggest that mitogen or antigen-stimulated lymphocytes secrete a molecule that is chemotactic for both monocytes and basophils. Thus, in the absence of a basophil-specific chemotactic molecule, the preferential accumulation of basophils in certain types of delayed hypersensitivity skin reactions must be due to additional factors such as basophil chemotaxis augmentation factor.  相似文献   
65.
The arteriographic diagnosis of spontaneous, nontraumatic dissection of the internal carotid artery was made in 19 patients and confirmed at operation in ten. The tapered narrowing beginning in or about the carotid bulb and ending at the bony canal was a consistent finding. Four patients had associated aneurysm formation. All but one patient developed an acute hemispheric neurologic deficit as the initial symptom. The deficit was transient in ten and prolonged in eight. The dissection occurred in the outer layers of the media. None of the surgical specimens showed atherosclerosis. Surgical methods of management included segmental resection and grafting, thrombectomy and intimectomy, dilation, and simple ligation. Considerable improvement of luminal diameter occurred in six of seven patients whose arteries were left undisturbed.  相似文献   
66.
Effect of charcoal-broiled beef on phenacetin metabolism in man   总被引:1,自引:0,他引:1  
When charcoal-broiled beef was fed to human volunteers, who were then given phenacetin orally, the concentration of phenacetin in the plasma was lowered, but its half-life in the plasma was not changed. The data suggest that feeding charcoal-broiled beef enhances the metabolism of orally administered phenacetin in the intestine or during its first pass through the liver, or both.  相似文献   
67.
Official physical examinations of migrant workers upon immigration are required before work permits are issued. The screening of 74,983 applicants during 1972 to 1974 revealed sera reactive to serological tests for syphilis in 0-8 per cent. (range 0-5 to 1-1 per cent.) of all persons concerned and fifteen cases of early syphilis. The incidence of recent infections among immigrants is lower than that reported among the inhabitants of Vienna. General statistics on the spread of venereal diseases among immigrant workers are not available after they start work. Some evidence is provided by those who had to be traced for compulsory examination because they had defaulted from treatment or follow-up, because they were suspected of clandestine prostitution, or because they were reported to be sources of infection. 257 (60-6 per cent.) of 414 individuals who were wanted for reasons of syphilis control could be located and eighteen (7 per cent.) of those who were examined had early infectious lesions.  相似文献   
68.
A series of [(2-nitro-1-alkenyl)aryloxy]acetic acids was synthesized and tested in dogs for saluretic and diuretic activity. A number of these compounds exhibit a high order of activity on iv or po administration; representative of these is (E)-[2,3-dichloro-4-(2-nitropropenyl)phenoxy]acetic acid (5). The most highly active compounds are qualitatively similar in action to [2,3-dichloro-4-(2-methylenebutyryl)phenoxylacetic acid (ethacrynic acid) in causing a prompt increase in the excretion of water and of sodium and chloride ions in approximately equimolar amounts but are three to five times as potent. Potassium ion excretion is increased but less markedly than sodium excretion.  相似文献   
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