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S Sakakibara F D Wicks R K Gholson 《Biochemical and biophysical research communications》1977,76(1):158-166
contains two proteins (A and B) which together convert dihydroxyacetone phosphate and aspartate to quinolinic acid, a precursor of NAD. Although mammalian liver homogenate does not catalyze this reaction it contains a protein which will replace the B protein of the system. The behavior of the liver protein on Sephadex G-75 suggests it is much smaller than the B protein. Liver B protein also appears to contain tightly bound FAD while FAD is easily removed from the B protein. The pH optimum for the hybrid system A protein-liver B protein is 9.0 while in the pure system the optimum is pH 8.0. The hybrid system is inhibited by NAD to the same extent as the pure system. 相似文献
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Esophageal cancer involves multiple genetic alternations. A systematic codon usage bias analysis was completed to investigate the bias among the esophageal cancer responsive genes. GC-rich genes were low (average effective number of codon value was 49.28). CAG and GTA are over-represented and under-represented codons, respectively. Correspondence analysis, neutrality plot, and parity rule 2 plot analysis confirmed the dominance over mutation pressure in modulating the codon usage pattern of genes linked with esophageal cancer. 相似文献
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The association between advancing paternal age and increased risk of schizophrenia in the off-spring is well established. The underlying mechanisms are unknown. In order to investigate whether the psychosocial environment associated with growing up with an aged father explains the increased risk we conducted a study of all adoptive children in Sweden from 1955–1985 (n = 31 188). Their risk of developing schizophrenia or non-affective psychosis in relation to advancing age of their adoptive fathers’ was examined. We found no association between risk of psychoses and advancing adoptive paternal age. There was no support of psychosocial environmental factors explaining the “paternal age effect”. 相似文献