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91.
The utility of the mixed carboxylic-sulfonic acid anhydride stearoyl p-toluenesulfonate as a powerful, mild acylating agent for lipid synthesis is shown by the synthesis of rac 1,2-distearoyl-3-iodopropane, lecithin and a spin-labeled choline derivative from the corresponding alcohols. The method constitutes a significant improvement of earlier acylating methods. 相似文献
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The outdating of units of blood can be reduced by decreasing the amount of time they spend in an assigned or crossmatched status. This reduction can be achieved in a hospital by establishing a maximum surgical blood order schedule (MSBOS) which reduces the excessive number of units of blood crossmatched preoperatively for patients undergoing elective surgery. The various steps which occurred in the development of a MSBOS in a large general hospital are detailed and the projected reduction in the number of crossmatched units which can be achieved with the MSBOS is illustrated. illustrated. The projected number of units of blood transfused to patients during their hospitalization for 50 common primary surgical procedures in the United States during 1974 is presented as a basis for defining maximum blood orders for each procedure. 相似文献
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Cyclophosphamide therapy may occasionally cuase black pigmentation of the nails. We report five cases with this side effect and review the data on eleven cases in the literature. These changes start in the proximal nail beds and progress distally; on withdrawal of cyclophosphamide, clearing of the nail pigmentation proceeds in a similar fashion. The development of the nail pigmentation does not bear any relation to the primary condition for which cyclophosphamide was prescribed. The dose of the drug before the onset of pigmentation ranged from 1.2 to 12.3 g; the duration of treatment ranged from 10 days to 26 weeks. The mechanism of the nail pigmentation is unknown. 相似文献
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TR O''Brien WA Blattner D Waters E Eyster MW Hilgartner AR Cohen N Luban A Hatzakis LM Aledort PS Rosenberg WJ Miley BL Kroner JJ Goedert 《Canadian Metallurgical Quarterly》1996,276(2):105-110
Normal women produce small amounts of active androgens. When androgen levels are elevated, such as for example in the polycystic ovary syndrome, this is followed by the development of male physical characteristics and muscle mass, structure and function as well as android adipose tissue distribution and function. Psychological features and stress reactions also seem similar to those of men. Such women have an increased risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular disease. Recent data have shown that these physical, and psychological characteristics, as well as risk of ill health, are also found in the population of women selected at random. Women in the lowest quintiles of levels of sex-hormone-binding globulin--an indicator inversely related to active androgens--are at risk of developing hypertension, non-insulin-dependent diabetes mellitus and cardiovascular mortality. The mechanism probably includes muscular insulin resistance, following a relative androgen excess. It is thus apparent that androgens, even within the highest levels of the nonselected population of women, are powerful predictors of serious disease development. The population at risk might be as large as about 20% of middle-aged women. This is an area of female disease risk which requires more attention in screening and intervention procedures. 相似文献