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101.
In Escherichia coli, UV and many chemicals appear to cause mutagenesis by a process of translesion synthesis that requires some form of DNA polymerase III and the SOS-regulated proteins UmuD, UmuC and RecA. An analysis of SOS mutagenesis offers insights into the molecular basis of induced mutagenesis and into mechanisms of DNA damage tolerance.  相似文献   
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The authors present clinical and case material on two male triplets with aberrant gender identity. Their findings coincide with those of the few family studies reported in which there were two or more transsexual members; they also reveal patterns generally in keeping with the psychological determinants of transsexualism suggested by Stoller.  相似文献   
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Since it covers the lateral wall of the mastoid air system, the suprameatal triangle is of importance to otologic surgeons during mastoidectomy. Because of this clinical importance, topographic anatomy of the suprameatal spine and depression was studied on Anatolian skulls. In all, 363 male and 231 female skulls were studied. The most prevalent type of suprameatal spine resembled a crest and was found in both sexes on the right (77.6%) and left (80%) sides. The absence of a suprameatal depression was significantly higher in females (right 9.1%; left 8.7%) than in males (right 1.7%; left 2.5%). Suprameatal depressions were mostly shallow in female subjects, but were mostly observed in males to be at a medium depth or deep.  相似文献   
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Two models have been used to study the effects of ethanol on injuries of the central nervous system. The spinal cords of cats were injured by delivering a 200 gm-cm impact to the exposed dura mater. A second group of animals received a similar injury to the exposed dura mater overlying the cerebral hemispheres. The animals were divided into two groups, those that received an infusion of ethanol before injury, and control animals that received no ethanol. The parameters of injury used in this model produced small and insignificant lesions in those animals that received no ethanol; however, when the animals were pretreated with ethanol, a considerable increase in the extent of the injury was noted. These include alterations in membranes-bound enzymes and clotting mechanisms, and alteration of cell membranes through abnormal free radical reactions.  相似文献   
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A quantitative counterimmunoelectrophoresis technique has been applied to evaluation of RNA antibodies in serum and unconcentrated CSF. Serum anti-RNA antibodies have been found at high dilutions in some patients with infectious diseases, subacute panencephalitis and multiple sclerosis. RNA antibodies in CSF are significantly linked to oligoclonal aspect, i.e. to a synthesis of IgG inside the CNS.  相似文献   
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The Diabetes Association of greater Cleveland screened 307,000 individuals in the metropolitan area for diabetes with a 75-gm. oral load of carbohydrate. Of these subjects 12,600 (4.1 per cent) had a two-capillary blood glucose level of greater than 139 mg. per cent and were defined as positive. Seventy per cent of the positives were retested, and 65 per cent of these again had two-hour levels greater than 139 mg. per cent. Seventy-one per cent of the original screening values were between 104 and 199 mg. per cent. The rate of positivity on retesting increased with the original screening bracket reaching 90 per cent at an original screening level of 240 mg. per cent or higher. The frequency of positive retests also increased with age irrespective of whether the original screening level was less than or greater than 200 mg. per cent. The implications of this large detection experience for conducting future mass surveys for diabetes are discussed.  相似文献   
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