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41.
The formation of the components of the cell envelope of Acinetobacter sp. 199A was investigated by measuring the incorporation of [3H]leucine into protein, [14C]galactose into lipopolysaccharide, 32P into phospholipid, and [3H]diaminopimelic acid into peptidoglycan. Whereas the lipopolysaccharide and intrinsic protein of the outer membrane were stable, some of the regularly arranged surface protein, the alpha-protein, was lost into the growth medium. Only newly synthesized alpha-protein was lost. The peptidoglycan of the murein layer was also labile. Selective inhibition of the formation of individual components of the cell envelope with penicillin, chloramphenicol, and bacitracin showed that incorporation of protein into the outer membrane required the simultaneous formation of complete lipopolysaccharide. The converse was not true: protein synthesis was not required for lipopolysaccharide incorporation. Formation of the outer membrane and the murein layer proceeded independently.  相似文献   
42.
Diethylsulphate solution was injected intraperitoneally twice a week to male mice B10.C3H having the wild-type colour at a 5 mg/kg dose. The treatment lasted 10 weeks, so that the total dose administered was 5-20 = 100 mg/kg. In fifth week after the end of the treatment these males were crossed to YT females homozygous for seven recessive mutant genes. In the control group all the F1 descendants were of wild-type colour, while in the experimental group among 5042 F1 mice derived from DES-treated spermatogonia there was one mutant d and 4 mosaics (3 with respect to the locus c and 1 with respect to the locusa). These results are interpreted as the evidence of the mutagenic effect of DES.  相似文献   
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In this review of 7,464 consecutive infants born at North Carolina Memorial Hospital, hemolytic disease from ABO incompatibility was found to be two to three times as common in black infants as in white infants. The statistical significance of the difference remained high as more restrictive criteria for ABO hemolytic disease were applied. ABO disease, serious enough to cause an indirect serum bilirubin of 15 mg/100ml or higher, had an incidence in black newborns as great as the incidence of Rh hemolytic disease in whites. In contrast, the general prevalence and severity of hyperbilirubinemia was not found to be higher in black newborns than in white infants. The difference cannot be attributed to differences in the prevalence of ABO blood groups between the two races. Policies of early discharge of newborns could be affected by the finding that ABO erythroblastosis is two to three times as common in black infants as in white infants.  相似文献   
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Cognitive performance in conversion hysteria   总被引:1,自引:0,他引:1  
In order to test some neurobiologically based assumptions pertaining to attention and memory dysfunction in conversion hysteria, a series of tasks was given to 17 hospitalized patients with hysterical conversion reaction and to a control group of nonpsychotic patients under conditions of nonstress and stress. The results indicated significant differences in performance between hysteria and control subjects. The former group, in comparison to controls, had heightened suggestibility, greater field dependency, and greater impairment of recent memory and vigilance-attention. A discriminant analysis indicated the feasibility of using such tests as objective diagnostic criteria for hysteria.  相似文献   
48.
Serum and urinary myo-inositol and urinary glucose were estimated by means of gas-liquid chromatography in 54 patients with glomerulonephritis with and without renal failure. myo-Inositol clearance was calculated and an index was formulated which reflected changes in glomerular filtration, tubular reabsorption and catabolism of myo-inositol by the kidney. Serum and urinary myo-inositol levels were increased in glomerulonephritis with a close correlation to the degree of renal failure. In advanced forms of glomerulonephritis, glomerular filtration, tubular reabsorption and catabolism of myo-inositol were shown to be markedly deranged. Evidence obtained showed further that a derangement of tubular reabsorption and catabolism of myo-inositol also accompany milder forms of glomerulonephritis without decreased glomerular filtration. The myo-inositol index value, especially, was increased in patients with signs of disease activity as indicated by a histological examination of the kidney tissue. The index can also be regarded as a highly sensitive test of renal failure. Low grade glucosuria was shown to be frequently associated with glomerulonephritis with renal failure. Evidence was produced which suggested that the tubular reabsorption of myo-inositol was deranged earlier than glucose reabsorption in glomerulonephritis, although they may share a common step in the reabsorption process. The data suggest that the estimation of serum and urinary myo-inositol has advantages in the evaluation of kidney function.  相似文献   
49.
A theoretical model is developed to predict pressure changes and velocity profiles within the foetal lung during its sporadic bursts of activity. Because of the small volume flow rates and relatively high frequencies, the linearised, unidirectional Navier-Stokes equations are used to calculate these values. About 70% of the pressure drop occurs in the first four generations and is an order of magnitude higher than the equivalent Poiseuille pressure drop. Velocity profiles, pressure falls within each generation together with the total pressure drop at different times during the cycle are illustrated.  相似文献   
50.
The distressing nature of laryngeal papillomatosis and lack of clinical progress in its treatment are reviewed. Presently accepted and investigative methods of therapy are reviewed with special attention being given to immune therapy. Support for the concept of a viral etiology is discussed and other etiologic agents considered. Known and possibly significant roles of wart virus antibodies are discussed and the importance of complex interplay between maternal and fetal immune systems explored as a possible explanation for some puzzling aspects of laryngeal papillomatosis. Finally, a proposed experimental design is outlined, the purpose of which is to provide a useful animal model to investigate immune changes in laryngeal papillomatosis, as well as effects of surgical or medical therapy.  相似文献   
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