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E MOLKE JENSEN K. A. THIESSEN AA. CHRISTENSEN 《Acta anaesthesiologica Scandinavica》1986,30(2):109-110
The effect of 4 mg oral naloxone on preoperative gastric volume and pH of gastric aspirate was studied in a double-blind, randomized study. Twenty patients received 10 ml of naloxone (4 mg) mixed with 10 ml of orange juice, and 20 patients received 10 ml of isotonic saline mixed with 10 ml of orange juice, 2 h before surgery. Gastric content was obtained immediately after intubation of the trachea. No significant difference in gastric volume and pH of gastric aspirate was found between the two groups. It is concluded that naloxone does not affect gastric emptying and gastric acid secretion to a degree great enough to protect against aspiration of gastric contents into the lungs. 相似文献
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H M Dashti H al-Sayer A Behbehani J Madda J T Christenson 《Journal of the Royal College of Surgeons of Edinburgh》1992,37(1):23-28
Repeated administration of carbon tetrachloride (CCl4) induces liver cirrhosis, possibly because it involves the production of free radicals. In order to evaluate the effect of free radical scavengers such as superoxide dismutase (SOD) and allopurinol in the pathogenesis of liver cirrhosis, rats were subjected to repeated CCl4 administration with and without scavengers. Four groups of animals were studied: CCl4 plus SOD (group 1), CCl4 plus allopurinol (group 2), CCl4 alone (group 3) and olive oil (group 4, normal controls). Analysis of plasma and tissue concentrations of trace elements was performed and histopathological patterns were studied in all groups after 7 weeks of repeated intraperitoneal administration of the solutions. Plasma levels of zinc and selenium were significantly lower in all experimental groups, with reciprocal elevation of manganese and copper. Copper and manganese content in the liver tissue was significantly higher in all three experimental groups. The zinc content was elevated in groups receiving CCl4 alone (group 3) or with allopurinol (group 2). The liver selenium, however, was significantly lower in these two groups. The copper:zinc ratio for plasma was 0.78 in the control group, 1.6 in the CCl4 group, 1.3 in the allopurinol group and 1.5 in the SOD group. For liver tissue, the ratio was 0.07 for controls, 0.17 for CCl4, 0.11 for allopurinol and 0.28 for the SOD group. The changes in trace element content correlated with the severity of cellular damage observed microscopically in the liver. The higher the copper:zinc ratio, the more advanced and extensive was the microscopic evidence of liver injury after CCl4 challenge. 相似文献
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Smoking and female infertility: a systematic review and meta-analysis 总被引:11,自引:10,他引:11
The high prevalence of smoking among women in their reproductive years
continues to be a matter of concern. The negative effects of smoking on
general health are well known, but smoking may also affect fertility. The
objective of the present study was to perform a systematic review of the
literature to determine whether there is an association between smoking and
risk of infertility in women of reproductive age, and to assess the size of
this effect. In the 12 studies used for this meta- analysis, the overall
value of the odds ratio (OR) for risk of infertility in women smokers
versus non-smokers was 1.60 [95% confidence interval (CI) 1.34-1.91].
Studies of subfertile women undergoing in-vitro fertilization (IVF)
treatment also show a reduction in fecundity among women smokers. A
meta-analysis of nine studies found an OR of 0.66 (95% CI 0.49-0.88) for
pregnancies per number of IVF- treated cycles in smokers versus
non-smokers. Despite the potential limitations of meta-analyses of
observational studies, the evidence presented in this review is compelling
because of the consistency of effect across different study designs, sample
size and types of outcome. However, continued reassurance is needed that
the calculated overall effect is not in fact due to confounding variables.
相似文献