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991.
BACKGROUND: Several recent reports have described hypotensive transfusion reactions in patients receiving platelet concentrates (PCs) filtered through white cell-reduction filters. It is well known that a negatively charged surface activates the contact system, consisting of factor XII, prekallikrein, and high-molecular-weight kininogen. STUDY DESIGN AND METHODS: To clarify the mechanisms of these hypotensive reactions, the possibility that white cell-reduction filtration activates the contact system was examined. Venous blood plasma bradykinin levels were also measured in patients receiving PC transfusions through filters. RESULTS: None of the measured values were changed by filtration through a positively charged filter. However, filtration through a negatively charged filter resulted in a decrease in the amounts of prekallikrein and an increase in the amount of bradykinin generated, which indicated the activation of the contact system. The bradykinin level was inversely related to the activity of angiotensin-converting enzyme (ACE) in the PCs and was elevated by addition of an ACE inhibitor. Although the venous blood plasma bradykinin level did not change in two patients with a normal ACE activity during PC transfusion through the negatively charged filter, two patients who had decreased ACE activity, showed a significant increase in bradykinin during the transfusion. CONCLUSION: These results suggest that the generation of a large amount of bradykinin by filtration of PCs through a negatively charged filter might cause hypotensive reactions in patients with decreased ACE activity. The clinical significance of bradykinin generation requires further study.  相似文献   
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PSK, extracted from mycelia of a strain of Coriolus versicolor, was administered to groups of 20 male Wistar rats before and during treatment with 3'-methyl-4-dimethylaminoazobenzene (3-MDAB). After 24 weeks, the survival rates were significantly higher in the groups given PSK before or with the 3-MDAB than in groups not given PSK or given PSK after 12 weeks of 3-MDAB treatment. Blood alpha-fetoprotein levels, determined every four weeks, increased in all groups after 3-MDAB treatment, but were significantly lower in the groups given PSK before or with the 3-MDAB than in the other groups. The results indicate that PSK had a suppressive effect on 3-MDAB-induced hepatocarcinogenesis.  相似文献   
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Selection of treatment for ulcerative colitis is based on the definition of clinical severity. In those medication is a main course. Mild and moderate cases are treated mainly with salicylazosulfapyridine or mesalazine. Patients with proctitis-type are added betamethazone suppositories and those with left-sided and total colitis-type predonisolone enema therapy simultaneously. If there is no response, they are given additional oral predonisolone. Even after remission, patients should be carefully observed. A good patient-physician relationship, continuation of maintenance therapy, and periodic follow-up examinations using colonoscopy or barium enema are essential to successful long-term management of this disease. Patients who have repeated relapsing should receive the stronger treatment, according to the endoscopic findings and clinical course in addition to the clinical severity.  相似文献   
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The study was carried out to evaluate the therapeutic effects of zanamivir, a highly selective, potent and specific inhibitor of influenza A and B virus neuraminidases, in adult patients with acute influenza-like illness. Patients who presented within 36 h of the onset of influenza-like symptoms were randomly assigned to receive one of three treatments, twice daily, for 5 days: 10 mg zanamivir powder for inhalation (zanamivir inhalation group), 10 mg zanamivir powder for inhalation plus 6.4 mg zanamivir nasal spray (zanamivir inhalation plus intranasal group) or placebo (placebo group). The primary end point was the time to alleviation of the three major symptoms (fever, headache and myalgia). The secondary end point was the time to alleviation of five influenza symptoms (fever, headache, myalgia, cough and sore throat). One hundred and sixteen patients with influenza-like illness were recruited to the study. No differences were observed between the two groups of patients who received zanamivir (inhalation group or inhalation plus intranasal group). Patients who received zanamivir recovered significantly faster (median 3 days to recovery) than the patients in the placebo group (median 4 days to recovery; P < 0.01). Topically administered zanamivir was well tolerated. This study confirms that in adults, topically administered zanamivir is well tolerated and is effective in reducing the time to alleviation of influenza symptoms.  相似文献   
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