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991.
992.
JR Harnes 《Canadian Metallurgical Quarterly》1976,236(4):346-347
993.
A patient with an anomalous insertion of the right hepatic duct into the cystic duct was noted during cholecystectomy and confirmed by operative cholangiography. This case and related anomalies of the bile ducts are of sufficient importance that, because of the technical difficulties and dangers incidental to their presence, no surgeon who operates on the gallbladder and bile ducts can afford to be unaware of their existence. Adequate exposure, careful dissection, and accurate knowledge of the regional anatomy plus a realization of the frequency and multiplicity of abnormalities of the extrahepatic biliary tree are requisites for safe biliary tract surgery. In addition, carefully performed operative cholangiography can be an indispensable aid in the clarification of anatomic variations. In case of recognized operative injury to the extrahepatic biliary tree, primary repair or biliary-intestinal anastomosis can usually be carried out with good results. 相似文献
994.
995.
'Eleven-plus' school examination scores were obtained for 851 Birmingham children residing since birth in a lead-polluted area and 1642 children residing in two similar but unpolluted areas. It was found that the children in the lead-polluted area actually scored higher on the average than children in the control areas. Within the area of lead contamination, children living closest to the source of pollution did not have significantly lower scores than children living further away. The results indicate that lead pollution of the magnitude reported in this investigation did not have a demonstrable effect on the mental capabilities of children in the affected community. 相似文献
996.
Biological role of alcohol dehydrogenase in the tolerance of Drosophila melanogaster to aliphatic alochols: utilization of an ADH-null mutant 总被引:1,自引:0,他引:1
The toxicity of the first eight primary alcohols and of four secondary alcohols was compared in a wild-type strain (having active ADH) and an ADH-negative mutant. Differences between LC50 measured in the two strains allowed an evaluation of the biological activity of the enzyme. In vitro, ADH is mainly active on secondary alcohols, while in vivo its main role is the detoxification and metabolism of ethanol. These observations suggest that originally ADH was involved in unknown metabolic pathways and that its utilization in ethanol metabolism could be a recent event. 相似文献
997.
C Gomez-Sanchez OB Holland JR Higgins DC Kem NM Kaplan 《Canadian Metallurgical Quarterly》1976,99(2):567-572
To investigate the control of aldosterone secretion, non-stress levels of serum aldosterone, corticosterone, and prolactin, and renin activity were determined at 4-h intervals during 24-h light-dark cycles in adult male rats on regular and low-sodium diets. Circadian rhythms of plasma aldosterone, prolactin, and corticosterone concentrations and of serum renin activity were demonstrated during a regular sodium diet. When the rats were on a low-sodium diet, a circadian rhythm of serum corticosterone and aldosterone concentration was observed, but there was no circadian variation in serum renin activity or in serum prolactin concentration. Serum aldosterone concentration correlated with serum corticosterone concentration (r = 0.48) and serum renin activity (r = 0.36) during a low-sodium diet. Serum prolactin concentration did not correlate with serum aldosterone concentration or serum osmolality. These data are compatible with a role for renin and ACTH, but not for prolactin, in the modulation of aldosterone secretion in the rat. 相似文献
998.
999.
1000.
Partial purification of rabbit aorta contracting substance-releasing factor and inhibition of its activity by anti-inflammatory steroids 总被引:1,自引:0,他引:1
Rabbit aorta contracting substance-releasing factor (RCS-RF) is found in perfusates from guinea pig lungs during anaphylaxis. It has been identified as a small peptide which releases arachidonic acid from lung tissue, thus generating prostaglandin endoperoxides and tbromboxanes and causing bronchocconstriction. Anti-inflammatory steroids block the release of arachidonate by RCS-RF. In this activity their relative potency is very similar to their relative anti-inflammatory potency, suggesting that the two actions may be related. 相似文献