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A number of flavonoids isolated from Lonchocarpus spp. were evaluated for their antiprotozoal and cytotoxic activity. Flavone 6 and chalcone 7 were found to be the most active against Leishmania parasites and against cell cultures of Leukemia P388DI and adenocarcinoma prostate PC-3.  相似文献   
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Nutrition plays a key role in many aspects of health and dietary imbalances are major determinants of chronic diseases including cardiovascular disease, obesity, diabetes and cancer. Adequate nutrition is particularly essential during critical periods in early life (both pre- and postnatal). In this regard, there is extensive epidemiologic and experimental data showing that early sub-optimal nutrition can have health consequences several decades later.  相似文献   
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Flow cytometer measurements were made of the basal variations in peripheral blood functional monocytes and granulocytes over the course of a training season (January to November) of a cycling team. Parallel determinations were made of plasma concentration of catecholamines (chromatography) and cortisol (RIA) in a search for neuroendocrine markers. The results showed the greatest phagocytic capacity to occur in the central months (March, May, and July), coinciding with the greatest number and highest level of competitive events with good correlation with a peak in epinephrine during these months (r(2) = 0.998 for monocytes and r(2) = 0.674 for granulocytes). No good correlations were found between phagocytosis and norepinephrine or cortisol. The highest values for phagocytosis and epinephrine concentration were found in May. These results suggest that blood epinephrine concentration could be a good neuroendocrine marker of sportspeople's phagocytic response.  相似文献   
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FTA® cards were used for long‐term storage of avian blood samples. Blood DNA was extracted by a simple method and used in PCR for sex identification of adult and nestling Great Grey Shrikes Lanius excubitor.  相似文献   
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When fibrin polymerizes in a strong magnetic field, it can be highly oriented. The structural diffraction study of the oriented polymer becomes thus possible. The magnetic birefringence can also be used to study the development of the polymer Fibrinogen in solution is weakly oriented in high magnetic fields. In this work we present complementary results and discussion. The validity of the comparison of the orientation parameters of fibrinogen and fibrin with those of other orientable known biological structures is discussed. The orientation of fibrin formed from fibrin monomer solution is compared to that of fibrin formed by the action of thrombin on fibrinogen. The conditions to obtain highly oriented fibrin gels suitable for three dimensional structure studies are also briefly discussed.  相似文献   
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