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31.
The pattern of arterial supply to the various parts (clavicular, sternocostal and aponeurotic) of the pectoralis major muscle was studied in 7 cadaver dissections and 10 angiograms by injecting a radio-opaque substance. Three main arteries supplied the muscle, i.e. the pectoral branch of the thoracoacromial trunk (TAT-PB), the lateral thoracic artery and the perorating branch of the internal thoracic artery, supported by other branches of the TAT and the superior thoracic artery. It is observed that the TAT-PB, a chief vascular pedicle, anastomoses freely with other arteries and supplies most parts of the muscle. The present study is mainly focussed on the exclusion of the chief vascular pedicle of muscle to eliminate the confusion of previous studies and prevent the unnecessary hindrance and complications of the muscle flap. 相似文献
32.
S K Bhattacharya S R Tripathi C K Pradhan S K Kashyap 《Indian journal of experimental biology》1990,28(9):849-857
To examine the effects of heat and noise individually and jointly on certain physiological responses and cognitive and neuromotor based functions, 12 male participants were tested under 6 experimental conditions which resulted by combining 3 levels of heat (25 degrees, 30 degrees and 35 degrees C) and 2 levels of white noise (70 and 100 dB). The experiment was carried out in a controlled climatic chamber following two 6 x 6 latin square designs. The results indicated elevations in heart rate, oxygen uptake and body temperature due to the independent effect of heat or the combined effects of heat and noise. The independent action of noise was found to be depressive on the first two responses. On the neuropsychological effects, the heat adversely affected the speed in card sorting (by design configuration) and digit symbol tests, and also the accuracy and error rate in the reasoning ability test. The noise caused performance improvements in critical flicker frequency (simultaneous) and in error rates in card sorting (by design configuration). The combined effects of heat and noise indicated higher error rates in card sorting (by face value), decreased accuracy in reasoning ability and improvements in performance in accuracy scores and error rates in digit symbol test. 相似文献
33.
It is shown that and how it is possible to single out the chain fold which is thermo-dynamically most stable. The suggested approach is based on two physical ideas: A "molecular field" approximation permits to examine all protein structures which belong to the same "folding pattern". Only a limited set of the "potentially stable" folding patterns have to be examined. The general approach is illustrated by calculations of the stable folds for two beta-domains. 相似文献
34.
Effect of aflatoxin B1 on chromatin-bound ribonucleic acid polymerase and nucleic acid and protein synthesis in germinating maize seeds. 下载免费PDF全文
The treatment of germinating maize seeds (cv. Ganga 2) with aflatoxin B1 resulted in suppression of ribonucleic acid (RNA), protein, and deoxyribonucleic acid (DNA) synthesis at 3, 4, and 5 h, respectively. At or below the concentrations inhibitory for these in vivo syntheses, the toxin inhibited chromatin-bound DNA-dependent RNA polymerase activity. The synthesis of both polyadenylated and non-polyadenylated RNA was inhibited, but the effect on the former was more pronounced. Equilibrium dialysis and difference spectral and viscometric analyses showed a binding of aflatoxin B1 to DNA isolated from the seeds. It is proposed that the inhibition of RNA synthesis in maize seeds by the toxin is due to the interference with the RNA polymerase activity, which seems, at least partially, due to the impairment of DNA template functions. 相似文献
35.
James B. Orenberg Kristi M. Kjos Reva Winkler Joseph Link James G. Lawless 《Journal of molecular evolution》1982,18(2):137-143
Summary The interactions of Ni(II) cation with a representative suite of purine bases and the respective nucleosides and nucleotides have been studied by ultraviolet difference spectroscopy. Apparent association constants, Kapp, were determined for each system at pH 7.0, using computer linear regression coupled with an iteration technique. The specificity of binding of Ni2+ for the purine nucleotides studied at pH 7.0 was 5-GMP > 5-IMP > 5-AMP; a similiar ordering was also found for the respective nucleosides and bases. In this study binding was not observed for the suite of pyramidines used, although a Ni2+ - cytidine complex has been observed (Fiskin and Beer, 1965). It was also found that Ni2+ bound more strongly to the purine 5-nucleotides than to the respective nucleosides and bases. These trends are explained in terms of metal-ligand bonds and available bonding positions on the ligands. A role for metal-ion-nucleotide types of complexes is suggested in the processes that might have given rise to the origin of life. 相似文献
36.
Dr. D. P. Tripathi S. L. Mehta Professor Dr. N. G. P. Rao 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1981,59(2):113-116
Summary Amino acid composition of proteins from anthers of milo and Indian origin male steriles were determined. Comparison of amino acid between A and B lines showed lower contents of histidine, threonine, glutamic acid, glycine, leucine and phenylalanine and higher contents of alanine, serine, proline and tyrosine in line A compared to line B. Alanine content in anthers of A lines was more than two fold higher than that in the anthers from B lines. Marked differences in amino acid composition of anthers of A and B lines are suggestive of their involvement in male sterility. Cytoplasmic male steriles of Indian origin M35-1A and M31-2A showed greater similarity but differed from milo, VZM2A and B. 相似文献
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Action of trypsin on glycinin. Mixed-type proteolysis and its kinetics; molecular mass of glycinin-T
A D Shutov J Pineda V I Senyuk V A Reva I A Vaintraub 《European journal of biochemistry》1991,199(3):539-543
The formation of a relatively stable high-molecular-mass product on trypsin hydrolysis of glycinin (glycinin-T) is interpreted to be a result of 'zipper' proteolysis. Evidence of parallel one-by-one degradation of glycinin occurring after the formation of glycinin-T is presented. At a relatively low concentration of the substrate, the one-by-one proteolysis proceeds as a first-order reaction. A method of determination of the changes in the molecular mass of a protein during the mixed-type proteolysis and some other parameters of this process is developed on the basis of the analysis of the proteolysis kinetics. The value of the molecular mass of glycinin-T calculated by means of this method makes up 70% of the initial molecular mass and coincides with the result of direct determination by gradient gel electrophoresis. 相似文献
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