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51.
Pfister GC  Puffer JC  Maron BJ 《JAMA》2000,283(12):1597-1599
Context  Sudden death in young competitive athletes due to unsuspected cardiovascular disease has heightened interest in preparticipation screening. Objective  To assess screening practices for detecting potentially lethal cardiovascular diseases in college-aged student-athletes. Design, Setting, and Participants  A total of 1110 National Collegiate Athletic Association member colleges and universities were surveyed between 1995 and 1997, with 879 (79%) responding to the questionnaire. Main Outcome Measures  Information on the administration and scope of the preparticipation screening process was obtained from the team physician or athletic director; preparticipation screening forms were evaluated for content and compared with 12 items recommended by the 1996 American Heart Association (AHA) consensus panel screening guidelines. Results  Preparticipation screening was a requirement at 855 (97%) of 879 schools, was performed on campus at 713 schools (81%), and was required annually by 446 schools (51%). Team physicians were responsible for examinations at 603 (85%) of 713 schools with on-campus screening, although 135 of these schools (19%) also approved nurse practitioners and 244 schools (34%) allowed athletic trainers to perform examinations. Of the history and physical examination screening forms analyzed from 625 institutions, only 163 schools (26%) had forms that contained at least 9 of the recommended 12 AHA screening guidelines and were judged to be adequate, whereas 150 (24%) contained 4 or fewer of these parameters and were considered to be inadequate. Smaller Division III schools were more likely than larger Division I schools to have inadequate screening forms (30% vs 14%; P<.001). Relevant items that were omitted from more than 40% of the screening forms included history of exertional chest pain, dyspnea, or fatigue; familial heart disease or premature sudden death; and physical stigmata or family history of Marfan syndrome. Conclusion  The preparticipation screening process used by many US colleges and universities may have limited potential to detect (or raise the suspicion of) cardiovascular abnormalities capable of causing sudden death in competitive student-athletes.   相似文献   
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Nipah virus (NiV) is an emerging zoonotic paramyxovirus that causes severe disease in humans and livestock. Due to its high pathogenicity in humans and the lack of available vaccines and therapeutics, NiV needs to be handled in biosafety level 4 (BSL-4) laboratories. Safe inactivation of samples containing NiV is thus necessary to allow further processing in lower containment areas. To date, there is only limited information available on NiV inactivation methods validated by BSL-4 facilities that can be used as a reference. Here, we compare some of the most common inactivation methods in order to evaluate their efficacy at inactivating NiV in infected cells, supernatants and organs. Thus, several physical and chemical inactivation methods, and combinations thereof, were assessed. Viral replication was monitored for 3 weeks and NiV presence was assessed by RT-qPCR, plaque assay and indirect immunofluorescence. A total of nineteen methods were shown to reduce NiV infectious particles in cells, supernatants and organs to undetectable levels. Therefore, we provide a list of methods for the safe and efficient inactivation of NiV.  相似文献   
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Pharmacological effects of green tea on the gastrointestinal system   总被引:11,自引:0,他引:11  
Green tea is rich in polyphenolic compounds, with catechins as its major component. Studies have shown that catechins possess diverse pharmacological properties that include anti-oxidative, anti-inflammatory, anti-carcinogenic, anti-arteriosclerotic and anti-bacterial effects. In the gastrointestinal tract, green tea was found to activate intracellular antioxidants, inhibit procarcinogen formation, suppress angiogenesis and cancer cell proliferation. Studies on the preventive effect of green tea in esophageal cancer have produced inconsistent results; however, inverse relationships of tea consumption with cancers of the stomach and colon have been widely reported. Green tea is effective to prevent dental caries and reduce cholesterols and lipids absorption in the gastrointestinal tract, thus benefits subjects with cardiovascular disorders. As tea catechins are well absorbed in the gastrointestinal tract and they interact synergistically in their disease-modifying actions, thus drinking unfractionated green tea is the most simple and beneficial way to prevent gastrointestinal disorders.  相似文献   
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The response of T cells in relation to the cell cycle has not been extensively studied. We have attempted to address this question using Jurkat T cells treated with cytostatic drugs known to arrest cells at various transition points of their cycle. We tested several concentrations of drugs that act at G1/S (hydroxyurea, lovastatin, thymidine), early S (aphidicolin, cyclosporin A, rapamycin) or G2+M (colchicine, nocodazole) in 24 h cultures. Cytofluorimetric analyses showed that cycling Jurkat cells were equally distributed between the G1 (44.9 ± 6.5%) and S (42.3 ± 8.0%) phases. Cell distribution in G2+M was 12.7 ± 2.8%. Hydroxyurea but not lovastatin increased the percentage of cells in S phase to ≈60–70% and both drugs decreased it to ≈30% in G1. Thymidine had no effects. Aphidicolin increased the distribution in S phase to ≈70% with a decrease in G1 to ≈30%. Cyclosporin A and rapamycin increased the percentage of the cells in G1 to ≈70% and decreased it to ≈25% in S phase. Nocodazole increased cell distribution in G2+M to ≈60% and induced a decrease in G1 to ≈10%. The effects of the drugs were not related to their toxicity and their limited efficiency raised the possibility that Jurkat cells possessed an intrinsic resistance to these xenobiotics. Time-course analysis showed (scanning electron microscopy) that the early morphological changes induced by colchicine were reversible. Drug efflux experiments (vinblastine) suggested that an ATP-dependent process could be involved. However, Northern blot analyses showed a weak signal for MDR1 (P-glycoprotein). In contrast, a probe for MRP (P-190) showed a strong signal in Jurkat and peripheral lymphocytes. The presence of drugs (cyclosporin A, nocodazole, thymidine) (24 h) did not upregulate its message and cell treatment with -butathione (S,R)-sulfoximine only moderately affected the efficiency of the glutathione S-conjugate MRP transporter. Our data suggest that the intrinsic multidrug resistance of leukemic Jurkat T cells does not appear to involve the MDR1 and MRP members of the ABC family of reverse drug transporters and these observations raise the possibility of the involvement of multifaceted mechanisms.  相似文献   
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Retained surgical sponges have been reported to occur after a diversity of surgical procedures, but transmural migration is a very unusual sequela. This article reports a case in which a retained surgical sponge eroded from the intra-abdominal space into the intestinal lumen, migrated distally, and spontaneously passed with defecation 12 weeks after the cesarean section. We performed a systematic review of the literature in Pubmed and found 64 cases of transmural migration of retained surgical sponges. Sixty-four cases have been reported of transmural migration, mainly after intra-abdominal surgery. The most frequent site of impaction is the intestine (75%), but we also found 2 cases that describe migration into the stomach and 7 into the bladder. Five more cases have been published describing transdiaphragmic migration. Only 4 cases describe a sponge spontaneously expelled through the rectum, whereas more than 93% needed re-intervention. We strongly advise only the use sponges with radiopaque markers during surgery and additional methodical wound/body cavity examination.  相似文献   
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