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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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We report 2 patients with myonecrosis due to Clostridium septicum and associated colon carcinoma and have reviewed the English language literature for all reported cases of atraumatic C. septicum infection. A total of 162 cases of C. septicum infection have been reported. Eighty-one percent of these patients had an associated malignancy. Thirty-four percent of all patients had associated colon carcinoma, while 40% had a hematologic malignancy. Thirty-seven percent of reported patients had an occult malignancy at the time of their infection with C. septicum. In many patients, the portal of entry was found in the large intestine. In a particularly lethal form (79% mortality) of C. septicum infection, known as "distant myonecrosis," infection metastatic from the initial site of infection causes severe myonecrosis, gangrene, and often death within hours of clinical detection. Overall, survival of patients with C. septicum infection is only 35%. Review of all cases of C. septicum infection suggests several conclusions. 1) Patients with malignancy, particularly colonic or hematologic, and patients with cyclic neutropenia who develop signs and symptoms of sepsis, especially with associated findings of abdominal pain or pain in an extremity, should be treated for possible clostridial infection. 2) C. septicum infection does not appear to be a result of a single specific defect in either humoral or cell-mediated immunity. Rather, it may occur in patients who are granulocytopenic and therefore prone to an enterocolitis. 3) Patients in whom an infection with C. septicum is found must undergo a vigorous search for malignancy following acute therapy.(ABSTRACT TRUNCATED AT 250 WORDS)  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   
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