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261.
262.
Preface   总被引:1,自引:0,他引:1  
Rotavirus diarrhea is the major cause of death of millions of children in developing countries besides causing economically significant malady in neonates of many domestic animals. In neonates, the infection is non-viremic, have very short incubation period, and manifests profuse diarrhea and severe dehydration. Concurrent infection with secondary pathogens may augment the disease severity. Diarrhea occurs due to virus-mediated destruction of absorption efficient enterocytes, activation of enteric nervous system, or due to a rotavirus enterotoxin. Diagnosis of the infection relies on conventional techniques like isolation in MA 104 cell lines, electron microscopy, electro-pherotyping, and various serological tests. Presently, diagnosis and molecular typing is performed using serotype specific RT-PCR, sequencing or genomic hybridization techniques. As the rotaviruses are known to exhibit extreme genetic diversity and outplay disinfection procedures, eradication of the pathogen is often difficult. Hence, for prevention, good management practices coupled with vaccination of dam for protecting young ones, has to be practiced. Recently, new generation prophylactic strategies including DNA vaccines, subunit vaccines, virus-like particles (VLPs) and edible vaccines have been found to induce sufficient levels of passive immunity. Aside to the infection in animals, zoonotic significance of the animal rotaviruses has to be further unearthed. In this review, efforts have been made to highlight the importance and prevalence of the disease in bovines, its pathogenesis along with preventive measures, salient features of rotaviruses and their inter-species transmission abilities, zoonotic implications, and a concise account of the infection in various domestic animals and poultry.  相似文献   
263.
alpha1-Adrenergic stimulation triggers glucose transport in the heart through the translocation of glucose transporter (GLUT) 1 and GLUT4 to plasma membranes, mediated by protein kinase C (PKC) isoforms. Evidence is emerging that dietary polyphenolic compounds may act not only as antioxidants but also by modulating PKC-mediated signaling. This study evaluated the ability of a green tea extract (GTE) to modulate alpha1-adrenoceptor-mediated glucose transport in rat cardiomyocytes. GTE supplementation decreased phenylephrine (PhE)-stimulated glucose uptake and GLUT4 recruitment. PhE stimulation activated PKC alpha, beta, delta, and epsilon, while GTE supplementation decreased the translocation of beta and delta isoforms, but not alpha and epsilon, supporting the notion that GTE directly affects PKC activation and is a beta and delta isoform-selective PKC inhibitor. Due to reactive oxygen species (ROS) involvement in pathological heart alterations, the observation that GTE is able to both inhibit effects originated by some PKC isoforms and counteract ROS deleterious effects could be important in the prevention/counteraction of these diseases.  相似文献   
264.
Modeling the relationships between environmental factors and the distribution at sea of species of conservation interest can be useful in predicting their occurrence from a local to a regional scale. This information is essential for planning management and conservation initiatives. In this study, generalized additive models (GAMs) were applied to investigate the influence of environmental, temporal and spatial variables on the catch rates of the twaite shad Alosa fallax (Lacepède) by the pelagic trawl fishery in the north‐central Adriatic Sea. Presence/absence and abundance [catch per unit effort (CPUE)] data between 2006 and 2012 were separately modeled, and the two models were then validated using a test data set. The most important factor influencing the presence and abundance of adult twaite shads was the spatial predictor (latitude × longitude). Two areas of major shads aggregations were observed, the most important of which being located near the estuaries of three main river systems of northern Italy. The twaite shad presence was also significantly affected by season, the largest and lowest occurrences being observed in autumn and spring, respectively. Among the environmental variables tested, only sea surface temperature was included in both models. Alosa fallax showed a wide thermal tolerance (6–27°C) with preference for temperature around 23°C. The model developed from the abundance data showed a moderate predictive power, whereas the accuracy of the presence/absence model was rather low. Some conclusions on the ecological requirements of A. fallax at sea arising from this study are useful to orient future monitoring and research programs and to develop effective conservation actions.  相似文献   
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