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The effects produced by nine dihydro-beta-agarofuran sesquiterpenes isolated from Crossopetalum tonduzii (1-8) and Maytenus macrocarpa (9) (Celastraceae) on the reversion of the resistant phenotype on a multidrug-resistant Leishmania line and their binding to recombinant C-terminal nucleotide-binding domain of Leishmania P-glycoprotein-like transporter were studied. The structures of the new compounds (1-5) were elucidated by spectroscopic methods, including (1)H-(13)C heteronuclear correlation (HMQC), long-range correlation spectra with inversal detection (HMBC), ROESY experiments, and chemical correlations. The absolute configuration of one of them (1) was determined by CD studies. The structure-activity relationship is discussed.  相似文献   
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Colorectal cancer is a complex disease from a genetic point of view because both genetic and environmental factors interact in its development. Only familial adenomatous polyposis (FAP) follows mendelian genetics, in that mutations of the APC gene lead to development of the tumours. Lynch syndrome is the most frequent form of hereditary colorectal cancer and appears to be associated with other types of extracolonic cancers. The genetic basis has been established as a defect in DNA mismatch repair genes, and there is genetic heterogeneity due to the involvement of several genes in this system. Germinal mutations in these genes predispose to appearance of the syndrome. The aim of this study is to describe the tumoral spectrum of 10 families, comprising a total of 488 individuals, from the island of Tenerife (Canary Islands) and to assess whether the geographical isolation of this population has changed any features of the tumoral spectrum of the syndrome in comparison with studies that cover larger geographical areas with more genetic exchange. From our results we can conclude that the genetic drift and consanguinity in this population with a demographic history of isolation did not significantly alter the tumoral spectrum of the syndrome. Our data confirm that families affected by Lynch syndrome are a high-risk population and should be closely monitored, since their careful supervision has been shown to be useful in preventing cancer. We also emphasize the importance of developing a complete family history that permits these families to be identified together with a mutational screening of DNA mismatch repair genes (mainly MLH1 and MSH2 genes) with the aim of a possible identification of members of a family that should be carefully monitored (the carriers of germline mutations in these genes), whereas the remaining members, originally, are no more at risk than the general population.  相似文献   
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OBJECTIVE: To report an influenza B infection with associated myocarditis and severe skeletal myositis. DESIGN: Case report. SETTING: Cardiac intensive care unit in a university-affiliated children's hospital. PATIENT: A 4-yr-old girl. RESULTS: The patient was successfully supported with extracorporeal membrane oxygenation for profound myocardial dysfunction and a combination of plasmapheresis and continuous venovenous hemodialysis for rhabdomyolysis and acute renal failure. CONCLUSIONS: This case provides a reminder that patients presenting with viral illness or myoglobinuria accompanied by renal failure, with or without associated myocarditis, may be demonstrating symptoms of influenza B.  相似文献   
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