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981.
The method of choice to determine erythrocyte glutamate-pyruvic transaminase (GPT) including rare variants was starch gel electrophoresis. Methods using agarose as gel medium were not reported to our knowledge. We present an adapted method using the Tris/maleate buffer system and an agarose of low endosmosis. The common as well as rare variant types of GPT were quickly and reliably separated. In addition, a method for the consecutive determination of esterase D (ESD) and GPT on the same gel using the malic acid buffer system is described.  相似文献   
982.
983.
984.
985.
Congress plays a central role in national environmental policy formation but appears ill equipped to set policy priorities and devise integrative legislation. Fragmentation of authority among a multiplicity of committees and subcommittees, especially in the House, contributes to these problems. This pattern is evident in the evolution of Superfund, the national program to clean up abandoned hazardous waste sites. The prolonged process of reauthorization in the 1980s contributed to serious program delay and failed to resolve a number of fundamental questions concerning the national cleanup effort. Institutional reforms could contribute to a more effective congressional role in future environmental policy deliberations.  相似文献   
986.
Supravital electrical excitability of muscles   总被引:1,自引:0,他引:1  
A new method of postmortem electrical stimulation of muscles, measuring the force of the reaction against time, is presented. Preliminary investigations have yielded the following results: The maximum force of reaction in response to a definitive stimulation, measured by a sensitive force transducer, decreases in proportion to the post mortem interval. Using this method, the mechanical reactions of muscles by electrical stimulation can be demonstrated over a much longer postmortem period as these movements are visible. The duration of postmortem reaction of different muscles seems to be much more uniform than was previously assumed. Occasionally, reactions of the M. orbicularis oculi can be seen for the longest time. The basal muscular tonus changes relative to time. The time course of a single force reaction also changes relative to the postmortal interval: the reaction becomes slower. It has been theoretically established that measurement of influencing factors such as temperature and pH in the tested muscle will enable the time of death to be more precisely estimated.  相似文献   
987.
988.
A current Supreme Court case concerning lawyer advertising, In re R.M.J., is analyzed in the context of a discussion of the diverse state regulations governing lawyer advertising and solicitation. The article considers the regulations in terms of their constitutionality, their tendency to impede effective advertising, and the effect they have on the legal profession's provision of information to potential clients about the nature, availability, and cost of legal services. Analysis of the major commercial speech cases, from Virginia State Board of Pharmacy to Central Hudson, indicates that many state rules infringe on attorneys' First Amendment rights.  相似文献   
989.
990.
A method is described for obtaining nondiffusing, nonfading fluorogenic zymograms for erythrocyte acid phosphatase variants separated by isoelectric focusing. The synthetic substrate 4-trifluoromethylcoumarin phosphate was impregnated into cellulose diacetate membranes and air-dried overnight. After isoelectric focusing, the substrate overlay membrane was rehydrated in 0.05M citrate buffer, pH 4.0, lightly blotted, and overlayed on the gel. A 5- to 10-min incubation at 37 degrees C produced intensely fluorescing, light-blue bands on the diacetate membrane. Interaction of the trifluoromethyl group on the substrate with hydrophobic regions of the diacetate membrane impeded diffusion, yielding a permanent zymogram. There were no discrepancies in phenotype determinations using this method when compared with the 4-methylumbelliferyl phosphate assay approach. Further, an increased number of conclusive calls were obtained (91.8 versus 79.5% and 54.1 versus 34.9%) with this new assay when compared with the 4-methylumbelliferyl phosphate substrate on known liquid bloods and questioned dried bloodstains, respectively.  相似文献   
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