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51.
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Acidosis inhibits catecholamine-induced lipolysis in vivo and in vitro. The lipolytic response of canine subcutaneous adipose tissue to short (5 min) nerve stimulations at 4 Hz was, however, not influenced by hypercapnic acidosis (pH 7.0). The steady state outflow of glycerol during a prolonged nerve stimulation at 4 Hz was inhibited by 40 per cent (p less than 0.05) at pH 7.0. Similarly, glycerol outflow during vasodilatation induced by a 4 Hz stimulation in alpha-blocked adipose tissue was inhibited by 37 per cent (p less than 0.05). Post-stimulatory glycerol outflow was, however, not influenced by acidosis. This poststimulatory glycerol outflow, which may represent a complex wash-out phenomenon, forms the largest part of the response to short nerve stimulations. It is suggested that steady state, rather than poststimulatory lipolysis should be studied in order to see the influence of treatments such as acidosis on responses to nerve stimulation.  相似文献   
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The absence of summation of the rate of methylation of positionally analogous cytidine residues in tRNA1Val, tRNAPhe, and tRNAMet in the case of simultaneous presence of two substrates in the incubation mixture was demonstrated by the method of mixed substrates. The same result was also obtained in the methylation of A19 (counting from the 3' end of the molecule) in tRNA1Val, tRNAPhe, tRNAfMet, tRNASer, and tRNAGlu individually and in the case of their mixing in pairs. These data are evidence that positionally analogous nucleotides in different RNAs are attacked by the same enzyme. Yeast tRNASer, already possessing a methyl group at the cytidine residue studied, proved to be an effective inhibitor of methylase, forming m5C with valine and phenylalanine tRNAs. The results obtained are evidence that differences in the primary and secondary structures at the site of methylation are not the deciding factors in the interaction of tRNA with methylases.  相似文献   
55.
Ultrastructural changes were found to occur in the mycelium of Actinomyces hygroscopicus, strain 33x, which produced an exocellular proteolytic enzyme during submerged fermentation, in both laboratory and semiindustrial conditions (in 100-1 fermenters). In the course of the enzyme accumulation, numerous vacuoles appeared in the hyphae, some hyphae became wider, and the cell walls were more loose. The greatest structural changes were found in the intracytoplasmic membrane systems. The ultrastructural changes of the mycelium are not presumably connected with the accumulation of the enzyme, but are the result of the differentiation of cellular structures during aging of the cells and their transition to the stage of autolysis.  相似文献   
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The article describes monitoring systems for following critically-ill patients, and cardio-resuscitation complex, apparatus for defibrillation, and short-term anaesthesy, cardiostimulators. All these units have been elaborated and serially produced by the Radioelectronic Medical Equipment Association. Their importance and place in providing the patients treatment and diagnosis in resuscitation and intensive care departments of the cardiological service are shown.  相似文献   
58.
We have developed a computer program for the rapid assessment of the primary structure differences between a protein of unknown sequence and a homologous known protein. Both proteins are reduced, alkylated, and digested with the same hydrolytic agent. The unfractionated peptide mixtures are submitted to automatic sequence analysis. Based on the knowledge of the reference sequence, the program utilizes the analysis data to identify all the potential peptides present in the two mixtures, determining their primary structure, homology degree, and molecular weight calculated both as integer MH+ and average mass variables. These fingerprints allow the user to easily identify the structural differences between the two proteins and clarify possible doubts by a mass spectrometric analysis of the two mixtures. In order to verify the utility of the program, we provide an application example using the already reported data of two homologous proteins.  相似文献   
59.
In present manufacturing environment, the manufacturing flexibility has become one of the strategic competitive tools. Flexibility refers to the availability of alternative resources. These resources may have varied parameters, particularly related to physical and operating system. These physical and operating parameters of alternative resources may influence the system's performance with the changing levels of flexibility and operational control parameters such as scheduling rules. Is increase in a flexibility level provides desired improved performance output? If yes, than under what conditions of physical and operating parameters and under which control strategy (CS)? Is improved performance is present at all increasing levels of flexibility? Flexible manufacturing system (FMS) being consist of numerous physical and operating parameters and complex in nature, the solution to these questions can provide an understanding of the productive levels of flexibility for a given physical and operating parameters of an FMS. This paper establishes the need of modelling of the physical and operating parameters of flexible manufacturing system along with flexibility and presents a simulation study under Taguchi's method analysis of these parameters. The paper contributes an approach to study the impact of variations in physical and operating parameters of an FMS and to identify the level of these variations that do not restrict the advantages of flexibility. The results show that the expected benefits from increasing the levels of flexibility and a superior CS may not be achieved if the physical and operating parameters of alternative machines have variations. Taguchi's method analysis indicates that relative percentage contribution of variations in physical and operating parameters of alternative resources should be negligible or minimum in the performance of FMS. Their increasing relative contribution may restrict the advantages of flexibility. If these variations are higher than increase in flexibility level may be counter productive.  相似文献   
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