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Polymer-associated infection is a problem of increasing importance in modern medicine. In a new approach to prevent such infections we have modified polyvinylfluoride (TEDLAR) films by graft copolymerization with N-vinylpyrrolidone to which iodine can be complexed. Grafting reaction was performed by the preirradiation technique using an electron accelerator. Grafted films were then treated in Lugol's solution for at least 24 h. Release of free iodine from the films was determined either by titration or using the agar disc diffusion test, showing an iodine release for up to 4-5 days. The antimicrobial activity of the films was tested in bacterial adhesion measurements. Bacterial and fungal cells in the range of 10(3) to 10(6) cfu/cm2 polymer were found on control samples without iodine, whereas on iodine-complexed films no viable cells could be detected at least for 5 days or even longer. Thus, microbial adhesion and growth can be inhibited by iodine-containing polymers.  相似文献   
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A case report of a male aged 31 who, after a journey to Bangladesh, returned with a disease resembling acute hepatitis A. Closer study revealed a hepatitis E infection. He recovered in slightly over two weeks.  相似文献   
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Cerebrovascular responses to capsaicin in vitro and in situ.   总被引:4,自引:1,他引:3       下载免费PDF全文
1. The cerebrovascular effects of capsaicin have been examined in vitro, in feline isolated cerebral arteries (circular segments, 2-3 mm long, 300-400 microns extended diameter) and, in situ, in pial arterioles (diameter 40-200 microns) on the cortical surface of chloralose-anaesthetized cats. 2. In isolated middle cerebral arteries, low concentrations of capsaicin (10(-14)-10(-10) M) effected a concentration-dependent relaxation of vessels precontracted with prostaglandin F2 alpha. This relaxant response was markedly attenuated by repeated administration of capsaicin but was minimally affected by the presence of atropine, propranolol, cimetidine or spantide in the tissue bath. 3. In isolated middle cerebral arteries, higher concentrations of capsaicin effected a marked concentration-dependent contraction. This contraction was not modified by 10(-6) M phentolamine or 10(-6) M ketanserin. A markedly reduced contraction by capsaicin was found upon the removal of calcium ions from the buffer solution. Also the calcium entry blocker nimodipine reversed the capsaicin-induced contraction. 4. Subarachnoid perivascular microapplication of capsaicin around individual pial arterioles in situ elicited a biphasic response (an immediate vasoconstriction followed by a sustained vasodilatation). The maximum vasoconstriction was a 60 +/- 6% reduction in diameter from base line and the maximum vasodilatation a 38 +/- 7% increase in diameter. Vasodilatation occurred at lower concentrations of capsaicin (EC50, approximately 5 x 10(-8) M) than those required for vasoconstriction (EC50 3 x 10(-7) M). 5. Trigeminal ganglionectomy 10-16 days before the microapplication abolished the in situ vasodilator effects of capsaicin (10(-6) M) applied perivascularly, but was without effect on the vasoconstrictor actions of this agent.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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A standardized pharmacological model of biochemically induced osteoarthritis in the knee joint of laboratory animals was used for the study of a possible antidegenerative effect of ademetionine (S-adenosyl-methionine, active substance of Gumbaral) in-vivo. Four days after the initial induction of osteoarthritis by 2 intraarticular injections of 0.6 mg sodium iodoacetate into the left knee joint of adult hens, the therapy started with once-weekly intraarticular doses of 0.5 mg, 1.0 mg and 2.0 mg ademetionine over a period of 14 weeks. Quantitative monitoring of the intensity and progression of osteoarthritis was performed every 2 weeks by joint space measurements, topographic-radiological evaluations, and by a macroscopic post-mortem assessment of the joint cartilage and bone. These objective analytical parameters clearly demonstrated that weekly intraarticular doses of 1.0 mg ademetionine significantly reduced the intensity of degenerative processes compared to the placebo (saline) treated joints. The antidegenerative effect of doses of 0.5 mg or 2.0 mg ademetionine were less pronounced and of no statistical significance. Our findings indicate an interesting therapeutic potency of ademetionine in experimental osteoarthritis and confirm the positive clinical observations as well as in-vitro results with this new drug by other researchers.  相似文献   
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We studied the reported frequencies of clinical complaints of neuromuscular hyperexcitability (muscle cramps and fasciculations) in random samples of 527 Dutch adults, who were and 253 Dutch adults, who were not suffering from musculoskeletal pain and tenderness. Data were collected by telephone-interview and by self-administered questionnaire. Muscle cramps and fasciculations were recorded more frequently in the category that suffered from musculoskeletal pain (p less than 0.001). This association warrants further investigation into the possible intrinsic role of neuromuscular hyperexcitability in musculoskeletal pain and primary fibromyalgia.  相似文献   
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