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381.
Russian Journal of Bioorganic Chemistry - In this study, a new class of furochromone derivatives bearing β-naphthol was synthesized via one-pot multicomponent reactions. First, condensation...  相似文献   
382.
Plasmonics - The most of the present biosensors are concentrated on the electrochemical techniques. Here, a novel one-dimensional phononic crystal (1D PnCs) sensor, which is adequate for sensing...  相似文献   
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Tests were carried out to determine the effect of manufacturing procedures for a Camembert-type cheese from raw goats' milk on the growth and survival of Staphylococcus aureus organisms added to milk at the start of the process, and to study the possible presence of staphylococcal enterotoxin A in these cheeses. The initial staphylococcal counts were, respectively, 2, 3, 4, 5 and 6 log cfu ml−1. Cheese was prepared following the industrial specifications and ripened for 41 d. Detection of enterotoxins was done by the Vidas SET test and by an indirect double-sandwich ELISA technique using antienterotoxin monoclonal antibodies. Generally, numbers of microbes increased at a similar rate during manufacture in all cheeses until salting. During the ripening period, the aerobic plate count population and Staph. aureus levels remained stable and high. There was an approximately 1 log reduction of Staph. aureus in cheeses made with an initial inoculum of Staph. aureus greater than 103 cfu ml−1 at the end of the ripening period (41 d) compared with the count at 22 h. The level of staphylococcal enterotoxin A recovered varied from 1 to 3·2 ng g−1 of cheese made with an initial population of 103–106 cfu ml−1. No trace of enterotoxin A was detected in cheeses made with the lowest Staph. aureus inoculum used in this study.  相似文献   
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386.
Journal of Plant Research - Phelipanche aegyptiaca and Orobanche spp. are obligate plant root-parasitic weeds that cause extensive damage in agricultural crop plants. Their germination requires...  相似文献   
387.
The concentrations of 3 beta-hydroxy-5-cholestenoic acid, 3 beta,7 alpha-dihydroxy-5-cholestenoic acid, and 7 alpha-hydroxy-3-oxo-4-cholestenoic acid were determined in plasma from patients treated with cholestyramine or subjected to resection of the ileum or colon. The values were compared with those for conjugated and unconjugated C24 bile acids. Patients with an intact ileum but without colon had normal levels of cholestenoic acids. Patients treated with cholestyramine or with ileal resection had elevated levels of 7 alpha-hydroxy-3-oxo-4-cholestenoic acid (median values 189 and 233 ng/ml, respectively, compared to 85 ng/ml in controls). The levels of the other two C27 acids were normal in cholestyramine-treated and low in ileoresected patients and were positively correlated to each other but not to the 3-oxo-delta 4 acid. There were no consistent correlations between the levels of C27 acids and those of conjugated or unconjugated C24 bile acids. The results indicate an increased formation of 7 alpha-hydroxy-3-oxo-4-cholestenoic acid in subjects having a stimulated activity of cholesterol 7 alpha-hydroxylase.  相似文献   
388.
Exposure to cold caused an increase in AChE activity of the different brain regions of both Arvicanthis and Columbia and a decrease in the enzyme activity of Scincus midbrain. Heat exposure provoked variable changes in AChE activity of the various brain regions of the three experimental species. The changes in AChE activities may be one of the mechanisms by which birds and mammals tend to acclimatize themselves to various forms of stress. In reptiles, AChE activity varied with changes in ambient temperature and this is probably due to the adaptive significance of thermally directed changes in enzyme substrate affinity.  相似文献   
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Demographic and socioeconomic factors affecting infant mortality in Egypt   总被引:1,自引:0,他引:1  
This paper analyses the relative importance of demographic and socioeconomic factors with respect to their role in reducing infant mortality in Egypt. Logit analyses of data from a nationally representative sample of Egyptian households, and for urban and rural households separately, indicate that demographic factors have more effect on infant mortality than socioeconomic factors. The results also show the need to improve housing in urban areas and sewerage systems in rural areas in order to reduce infant mortality. One of the most important policy conclusions, however, concerns the importance of providing a vigorous educational campaign to enlighten mothers and prospective mothers in both rural and urban areas on the positive effects of breast-feeding, longer birth intervals, and fewer children on the survival of infants.  相似文献   
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