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41.
A Latin Square design has been used to test the responses of 24 relatively fit young women to 200 minute bouts of exercise performed over 5 day trials under each of three different ambient conditions: 15 degrees C (warm-warm; (WW)); -20 degrees C while inhaling, from a facemask, air heated to 18 degrees C (cold-warm; (CW)); and -20 degrees C (cold-cold; (CC)). In both of the cold environments, special clothing and boots were provided (insulation 0.47 degree C X watt-1 X m-2 and 0.62 degree C X watt-1 X m-2; (4 and 3 CLO units)). All three trials led to a small (0.6-0.7 degree C) rise of rectal temperature, but in the two cold environments mean body temperatures fell by over 1.0 degree C. A large increase of serum ketones occurred under all conditions, and the exercise respiratory quotient suggested some increase of fat utilization, WW (0.85) through CW (0.84) to CC (0.83). A fat loss of about 0.5 kg over the five days was confirmed by hydrostatic weighing and measurement of skinfold thicknesses. This was much less than the change previously observed in men, and moreover, it seemed to be independent of ambient conditions. Possible reasons why cold did not increase fat loss in these women include: a lower relative intensity of exercise; a greater stability of fat stores in women; avoidance of caffeine; a possible translocation of subcutaneous fat to deep fat depots; and a greater desire to "lose weight" irrespective of environmental conditions.  相似文献   
42.
The capsular polysaccharide of Klebsiella SK1 was investigated by methylation analysis, Smith degradation, and 1H NMR spectroscopy. The oligosaccharides (P1 and P2) obtained by bacteriophage ΦSK1 degradation of the polymer were studied by methylation analysis, and 1D- and 2D-NMR spectroscopy. The resulting data showed that the patent repeating unit is a branched pentasaccharide having a structure identical to the revised structure recently proposed for Klebsiella serotype K8 capsular polysaccharide.
The 2D-NMR data showed that one third of the glucuronic acid residues in the SK1 polymer are acetylated at O-2, O-3, or O-4. FABMS studies confirmed the presence of monoacetylated glucuronic acid residues. Thus, the relationship between the Klebsiella K8 and SK1 polymers is akin to that found for Klebsiella polysaccharides K30 and K33, which have been typed as serologically distinct yet their structures differ only in the degree of acetylation.  相似文献   
43.
NADPH-cytochrome c (P-450) reductase from liver microsomes of phenobarbital-treated rats has been purified in a single step by affinity chromatography on agarose-hexane-adenosine 2',5'-diphosphate. As determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, enzyme assay, and radioimmunoassay the protein obtained by this single step procedure is as pure as that isolated by multicolumn procedures.  相似文献   
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Using radioimmunoassay, the concentration of carbonic anhydrase III in the livers of adult male rats was found to be approx. 30-times greater than that observed in mature females. Castration of male rats led to a marked reduction in liver carbonic anhydrase III concentrations which could be partially restored to control levels by testosterone replacement. Administration of testosterone to ovariectomised female rats induced about a 5-fold increase in liver carbonic anhydrase III concentration. Immunoprecipitation analysis of the products of liver mRNA translation in vitro with antiserum specific for carbonic anhydrase III showed that hormonal control of the levels of carbonic anhydrase III in liver is mediated by changes in the amount of translatable carbonic anhydrase III mRNA. Marked changes in liver carbonic anhydrase III concentrations were also observed in developing and ageing male rats.  相似文献   
46.
Seventy patients with diverticular disease of the colon were treated with a high-residue, low-sugar diet including unprocessed bran. Follow-up for an average of 22 months showed marked relief of symptoms in 62 patients. Bowel habit was restored towards normal and abdominal discomfort relieved. Only seven patients were unable to give up the use of laxatives. Eight patients did not tolerate the bran diet, and one of these needed surgical treatment. None of the 62 patients who took the diet needed surgery.  相似文献   
47.
Spores of the Bacillus subtilis minicell-producing mutant div IV-B1 were germinated and grown to microcolonies in chambers which facilitate continuous observation of the developing clones with a phase-contrast microscope. Time lapse photographs were taken of 46 clones, covering the period from the beginning of outgrowth until at least two rounds of cell division had been completed. Cell lineages were constructed from contour length measurements of the photographs. These data include cell lengths, division site locations, and cell numbers in clones of various ages. From these data we have determined that the probability of a minicell being produced at any division by the div IV-B1 mutant is 0.31. The location of the abnormal division site which generates the first minicell produced in the outgrowing clone appears to be random with respect to the existing cell poles. In contrast, the location of the second abnormal division site, and hence the second minicell, is not random but rather occurs preferentially in proximity to the first minicell. This clustering of abnormal events suggests that division site location is related to pole age (generations), although other influences on minicell clustering cannot be ruled out at present.  相似文献   
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1. Lysosome-rich fractions were obtained from foetal liver tissues as early as 35 days uterine age. Foetal lysosomes showed the same ;structure-linked latency' and acid hydrolytic potentiality characteristic of their adult counterparts. 2. The osmotic stability of lysosome-rich fraction from foetal guinea-pig liver tissue was greater than that of the corresponding adult lysosome fractions, p-nitrophenyl-phosphatase being used as marker enzyme. 3. The observation was confirmed by using beta-glycerophosphatase and phenolphthalein beta-glucuronidase as alternative marker enzymes. p-Nitrophenyl phosphate and beta-glycerophosphate appear to act as substrates for the same enzyme. 4. By using p-nitrophenylphosphatase activity measurements it was shown that the osmotic stability of foetal lysosomal fractions decreased with increasing foetal age, but at no time achieved the degree of osmotic instability characteristic of adult lysosomal fractions. 5. The correlation of these findings with the intracellular environment of lysosomes is discussed.  相似文献   
50.
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