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941.
942.
Many of the conventional agarose phosphoglucomutase (PGM) subtyping systems presently in use fail to provide a good separation between the 1 + and 2- bands as well as the 2+ band and the more anodic moving bands. Use of a 1-mm-thick gel composed of 1% ISO GEL (FMC Corp.) and phosphate-citric acid gel and tank buffers with a pH of 5.3 provided exceptionally good separation between all four of the major subtyping bands. The additional criteria for this procedure is a voltage of 21 V/cm and a run time of 4 h. Utilization of this procedure using case samples of varied ages proved the reliability of the procedure. Also examined were the effects of several reducing agents on the enzyme band patterns and the use of this system for the simultaneous determinations of the adenosine deaminase (ADA), erythrocyte acid phosphatase (EAP), and adenylate kinase (AK) enzyme phenotypes. 相似文献
943.
944.
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946.
Isotachophoresis, a technique to separate components by constant current electrophoresis, was used to differentiate between bloodstains of male, female, menstrual, bovine, and ovine bloods on cotton cloth and filter paper. Bloodstain analysis by isotachophoresis of stains from male and female subjects showed identical cationic patterns, but gave different profiles in the anionic system. Plasma had one extra peak in the anionic system when compared to the profile of serum. This extra peak is due to the presence of fibrinogen in plasma. Some hemoglobin peaks overlapped with serum protein peaks, but these could be identified by comparisons at lower concentrations. Menstrual blood had a much different pattern than normal human blood as was expected since many more compounds are found in menstrual blood than in normally circulating blood. Human, bovine, and ovine bloodstains showed different profiles both in the cationic and anionic systems. These results indicate that isotachophoresis can be used for the rapid and simple analysis of bloodstains to differentiate reliably human male, female, and menstrual blood and also to distinguish human bloodstains from those of cattle or sheep. 相似文献
947.
948.
A method was developed for the specific determination of digoxin and digitoxin, as well as their semisynthetic derivatives and dependent cardioactive metabolites, in autopsy samples of heart and kidney. A collective of six patients on long-term treatment with therapeutic doses of beta-acetyldigoxin had a mean myocardial digoxin content of 46.1 +/- 25.0 ng/g (SD); kidney: 50.3 +/- 30.3 ng/g. Digoxigenin bisdigitoxoside represented the second most important metabolite in heart and kidney; digoxigenin monodigitoxoside and digoxigenin follow, respectively. In a collective of seven patients on maintenance treatment with digitoxin, the mean tissue levels were higher but the metabolic pattern was similar (myocardial digitoxin content: 78.9 +/- 38.4 ng/g, renal content: 104.1 +/- 44.1 ng/g). The amount of digoxin formed by hydroxylation under long-term treatment with digitoxin in heart and kidney were approximately 10 ng/g. A case of digoxin intoxication differed both in the tissue content and in the metabolic distribution. 相似文献
949.
950.
The intake of 0.51 of water glass (sodium metasilicate; colloid pH 12.5) led to death within 1-1.5 h. Autopsy revealed alkali burns of the stomach mucosa. The stomach contained a small amount of liquid with a pH of 11.5. Histologically, numerous bronchioles and alveoles were filled with amorphous material. This material was chemically proved to be condensed water glass. The obstruction of large parts of the lungs by water glass led to an inhibition of alveolar gas diffusion, which may have been the cause of death. The transformation of the water glass from liquid to solid occurred in the lungs by means of the carbonic acid of expiration air. This was made possible because the pH of water glass had been changed by gastric secretions from 12.5 to 11.5. Water glass starts to solidify around pH 11.4-11.3. 相似文献