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91.
Paul S Chandra D Ray DD Tewari AK Rao JR Banerjee PS Baidya S Raina OK 《Veterinary parasitology》2008,153(1-2):143-146
A survey based on PCR assay of 18S SSU rRNA gene revealed a 30.2% infection with Cryptosporidium spp., out of 457 faecal samples collected from neonatal bovine calves across three different regions of India. The PCR-RFLP pattern of the gene in all the positive cases established the species as Cryptosporidium parvum. Highest prevalence was recorded in the monsoon months (37.3%) and in the calves showing acute diarrhoea (32.3%). The calves below 15 days of age were mostly affected (45.1%). The infection was more prevalent in the northern parts (35.4%) of the country than in the eastern or southern parts. Results indicated that C. parvum was the only species of Cryptosporidium prevalent in bovine calves in three different geographical regions of India. 相似文献
92.
Andrew O. Finley Sudipto Banerjee Alan R. Ek Ronald E. McRoberts 《Journal of Agricultural, Biological & Environmental Statistics》2008,13(1):60-83
This article investigates multivariate spatial process models suitable for predicting multiple forest attributes using a multisource
forest inventory approach. Such data settings involve several spatially dependent response variables arising in each location.
Not only does each variable vary across space, they are likely to be correlated among themselves. Traditional approaches have
attempted to model such data using simplifying assumptions, such as a common rate of decay in the spatial correlation or simplified
cross-covariance structures among the response variables. Our current focus is to produce spatially explicit, tree species
specific, prediction of forest biomass per hectare over a region of interest. Modeling such associations presents challenges
in terms of validity of probability distributions as well as issues concerning identifiability and estimability of parameters.
Our template encompasses several models with different correlation structures. These models represent different hypotheses
whose tenability are assessed using formal model comparisons. We adopt a Bayesian hierarchical approach offering a sampling-based
inferential framework using efficient Markov chain Monte Carlo methods for estimating model parameters. 相似文献
93.
94.
A blood cell type termed crystal cell in Drosophila functions in clotting and wound healing and requires Notch for specification and maintenance. We report that crystal cells express elevated levels of Sima protein orthologous to mammalian hypoxia-inducible factor-α (Hif-α) even under conditions of normal oxygen availability. In these platelet-like crystal cells, Sima activates full-length Notch receptor signaling via a noncanonical, ligand-independent mechanism that promotes hemocyte survival during both normal hematopoietic development and hypoxic stress. This interaction initiates in early endosomes, is independent of Hif-β (Τangο in Drosophila), and does not activate hypoxia response targets. Studies in vertebrate myeloid cells have shown a similar up-regulation of Hif-α protein in well-oxygenated environments. This study provides a mechanistic paradigm for Hif-α/Notch interaction that may be conserved in mammals. 相似文献
95.
96.
Banerjee RR Rangwala SM Shapiro JS Rich AS Rhoades B Qi Y Wang J Rajala MW Pocai A Scherer PE Steppan CM Ahima RS Obici S Rossetti L Lazar MA 《Science (New York, N.Y.)》2004,303(5661):1195-1198
The association between obesity and diabetes supports an endocrine role for the adipocyte in maintaining glucose homeostasis. Here we report that mice lacking the adipocyte hormone resistin exhibit low blood glucose levels after fasting, due to reduced hepatic glucose production. This is partly mediated by activation of adenosine monophosphate-activated protein kinase and decreased expression of gluconeogenic enzymes in the liver. The data thus support a physiological function for resistin in the maintenance of blood glucose during fasting. Remarkably, lack of resistin diminishes the increase in post-fast blood glucose normally associated with increased weight, suggesting a role for resistin in mediating hyperglycemia associated with obesity. 相似文献
97.
Tiago de Oliveira F Chanda A Banerjee D Shan X Mondal S Que L Bominaar EL Münck E Collins TJ 《Science (New York, N.Y.)》2007,315(5813):835-838
Iron(V)-oxo species have been proposed as key reactive intermediates in the catalysis of oxygen-activating enzymes and synthetic catalysts. Here, we report the synthesis of [Fe(TAML)(O)]- in nearly quantitative yield, where TAML is a macrocyclic tetraamide ligand. Mass spectrometry, M?ssbauer, electron paramagnetic resonance, and x-ray absorption spectroscopies, as well as reactivity studies and density functional theory calculations show that this long-lived (hours at -60 degrees C) intermediate is a spin S = 1/2 iron(V)-oxo complex. Iron-TAML systems have proven to be efficient catalysts in the decomposition of numerous pollutants by hydrogen peroxide, and the species we characterized is a likely reactive intermediate in these reactions. 相似文献
98.
Duck viral enteritis (DVE) was diagnosed in an outbreak of the disease in a resident population of Muscovy ducks (Cairina moschata domesticus) on a privately owned multispecies game bird production facility in Illinois, where it claimed 625 ducks. This disease condition had not been reported previously in domestic ducks in Illinois. Although other varieties and age groups of domestic waterfowl (i.e., black ducks, rhumen ducks, Pekin ducks, ducklings, and geese) were present on the game bird farm, the morbidity and mortality (100%) in this epornitic was solely limited to adult ducks of the Muscovy lineage. The clinical signs in the affected ducks were lethargy, diarrhea, dehydration, and death within 2-3 hr of onset of symptoms. Gross pathologic changes were nonspecific and included ecchymotic hemorrhage, effusion of fluid and blood within body cavities reflective of an acute systemic infectious disease. Light microscopic findings were necrosis of primarily digestive lining epithelium and variable lymphohistiocytic infiltration within mucosal and serosal connective tissues. Intranuclear inclusions resembling characteristic herpetic (i.e., Cowdry type A) inclusions were observed primarily in the digestive, respiratory, and reproductive tracts; liver; and spleen. Esophageal candidiasis, bacteriosis, and systemic Pasteurella anatipestifer infections, thought to be concurrent or opportunistic infections, were present in several ducks. DVE virus was demonstrated in infected Muscovy duck embryo fibroblast cells by direct DVE virus-specific fluorescent antibody staining. 相似文献
99.
Summary Inheritance of resistance to tomato leaf curl virus (TLCV) was studied in the progenies derived from interspecific crosses between TLCV resistant Lycopersicon hirsutum f. glabratum line B 6013 and five susceptible cultivars (HS 101, HS 102, HS 110, Pusa Ruby and Punjab Chhuhara) of L. esculentum. P1, P2, F1, F2, B1 and B2 progenies of the five crosses were artificially inoculated with local strains of TLCV by means of the vector whitefly, Bemisia tabaci (Genn.). and the disease reaction was studied in all the crosses. Reaction of parents, F1, F2 and backcrosses suggests that resistance derived from L. hirsutum f. glabratum B 6013 is based on two epistatic genes, one from the wild parent and one from the cultivated one, resulting in a 13:3 segragation in the F2. 相似文献
100.
S. K. Banerjee 《Euphytica》1971,20(3):430-434
Summary Some of the hybrid seeds obtained by interspecific crosses show lack of proper development of seed parts like embryo or endosperm. If such seeds are sown, no plant is usually obtained. However, if the internal details of the seeds are known prior to sowing, embryo culture method may be resorted to for the under-developed seeds and the unfortunate loss of hybrid plants may probably be avoided. The use of X-ray photography was found to be very promising and was employed to assess the internal condition of the hybrid seeds obtained from the interspecific crossing programme, viz, 1. Oryza sativa × O. officinalis, 2. Abelmoschus esculentus × A. moschatus, 3. Lycopersicum esculentum × L. pimpinellifolium and 4. Solanum melongena × S. testiculatum. The special advantages of this technique are, that a. it is possible to know the internal development of F1 seeds without causing any damage to them; b. knowing the condition of the seed, adequate care could be provided to individual seeds as judged by the radiographs; c. it is a very quick and sure method which could be used by the geneticists and breeders in their distant crossing programmes. 相似文献