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A study was carried out to determine whether spirochaetes are frequently associated with digital dermatitis in United Kingdom (UK) dairy cattle. Histopathological examination of lesions using a silver stain showed a large number of unidentified spirochaete-like organisms present in digital dermatitis hoof skin tissue in all examined biopsies. Immunocytochemical staining demonstrated that spirochaetes in skin lesions were identified by polyclonal antisera to Borrelia burgdorferi, Treponema denticola and Treponema vincentii (again all biopsies were positively stained), whereas monoclonal antibodies to B. burgdorferi and any Treponema pallidum did not stain any organisms in all biopsies. A PCR of 16S rRNA, previously shown to be specific for a new treponeme, was employed and produced positive results from 82.4% of digital dermatitis tissues. It is concluded that this spirochaete (or related spirochaetes), which is similar to human oral treponemes, is frequently associated with, and may be responsible for, pathological changes in digital dermatitis.  相似文献   
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In 2009, a pandemic influenza A virus (pH1N1) spread globally in humans and infected a broad range of captive animals with close human contact. In February 2014, a pH1N1 virus was isolated from a sloth bear with respiratory signs at a US zoo, demonstrating that recurring epidemics present an ongoing threat to animals, including threatened species. This is the first report of pH1N1 infection in sloth bears. To understand the sloth bear virus within the global context of pH1N1, phylogenetic trees were inferred including full‐length sequences from available non‐human, non‐swine hosts, representing four families in the order Carnivora and one order of birds. A combination of phylogenetic and epidemiological evidence strongly suggests the sloth bear was infected with a human‐origin pH1N1 virus, supporting the implementation of biosecurity measures to protect human and animal health.  相似文献   
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A database of the clinical chemistry results from unwell animals referred to Glasgow University Veterinary School, by general practitioners, was studied. This database contains over 60,000 records, from more than 25,000 animals, obtained over a period of 18 years. A four-year period was selected during which the instruments and methods used for these analyses were unchanged. The biochemical analyses made on plasma from those dogs when first presented to the veterinary school were scrutinised in detail. These data have been summarised in a tabular form using the first, fifth, 10th, 25th, 50th, 75th, 90th, 95th and 99th percentiles. The distributions of these values differ for different analytes and in particular do not conform to a normal curve. These data can be used to provide estimates of rarity to indicate the frequency with which extreme values associated with disease can be expected. Thus an individual datum can be flagged as high*, high**, high***, or high**** depending on whether it lies in the top 25 per cent, top 10 per cent, top 5 per cent or top 1 per cent, respectively, of cases in the hospital database. Low values can be flagged in the same way. This approach can complement the use of reference ranges from healthy animals to aid the interpretation of clinical biochemistry results from a new patient.  相似文献   
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Cortisol responses of Dorset and Scottish Blackface lambs were investigated at six ages between birth and seven days. There were four treatments: control handling and blood sampling (n = 52), tail docking (T) (n = 57), castration plus tail docking (CT) (n = 54), and intravenous adrenocorticotrophin (ACTH) injection (n = 60). Most lambs exhibited transient rises in plasma cortisol concentrations after treatment and the results in individuals were expressed as the area under the cortisol curve (integrated response). Postnatal changes in the integrated responses of control, T and CT lambs differed significantly between the two breeds; in Dorsets they increased markedly between four hours and one day and then decreased, whereas in Scottish Blackface lambs there were no significant changes. The cortisol responses of ACTH lambs decreased markedly between four hours and seven days in both breeds. The results shed light on postnatal changes in the activity of the hypothalamic-pituitary-adrenal axis and suggest for both breeds that the average increments in ACTH secretion caused by noxious stimuli increased markedly during the first one to three days after birth. Whether this reflected parallel increases in the levels of distress experienced by the lambs remains to be clarified.  相似文献   
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Modulation of postendocytic sorting of G protein-coupled receptors   总被引:1,自引:0,他引:1  
Recycling of the mu opioid receptor to the plasma membrane after endocytosis promotes rapid resensitization of signal transduction, whereas targeting of the delta opioid receptor (DOR) to lysosomes causes proteolytic down-regulation. We identified a protein that binds preferentially to the cytoplasmic tail of the DOR as a candidate heterotrimeric GTP-binding protein (G protein)-coupled receptor-associated sorting protein (GASP). Disruption of the DOR-GASP interaction through receptor mutation or overexpression of a dominant negative fragment of GASP inhibited receptor trafficking to lysosomes and promoted recycling. The GASP family of proteins may modulate lysosomal sorting and functional down-regulation of a variety of G protein-coupled receptors.  相似文献   
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OBJECTIVE: To assess tracking of energy and nutrient intakes between adolescence and young adulthood. DESIGN: Longitudinal study of a random sample of adolescents (aged 15 years at baseline). The extent of tracking of dietary intakes (assessed by diet history) was investigated using weighted kappa statistics (kappa). SETTING: Northern Ireland population survey. SUBJECTS: Adolescents who participated in the Young Hearts Project, Northern Ireland at age 15 years, and subsequently at young adulthood aged between 20 and 25 years (n=245 males, n=231 females). RESULTS: Despite overall increases in height and weight (both P<0.001), increases in body mass index in males (P<0.001) and body fatness in females (P<0.001), median reported intakes of energy (kJ kg(-1) day(-1)), carbohydrate (g day(-1)) and fat (g day(-1)) decreased (all P<0.001) over time. Expressed as nutrient densities (per MJ), diets at young adulthood were overall richer in thiamin, vitamin B6, total folate (all P<0.001), vitamin C (P<0.01) and vitamin D (P<0.05). Whereas the nutrient density of the males' diets decreased over time for calcium (P<0.05) and vitamin A (P<0.001), iron and riboflavin densities increased in the females' diet (P<0.001). Tracking of energy (MJ day(-1)) and nutrient intakes (expressed per MJ day(-1)) at the individual level was only poor to fair (all kappa<0.25), indicating substantial drift of subjects between the low, medium and high classes of intake with increasing age. CONCLUSIONS: These data suggest that individual dietary patterns exhibited at 15 years of age are unlikely to be predictive of dietary intakes at young adulthood.  相似文献   
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