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31.
The long-term probability of soil moisture stress in rainfed crops was mapped at 0.5° resolution over the Krishna River basin in southern India (258,948 km2). Measurements of actual evapotranspiration (Ea) from 90 lysimeter experiments at four locations in the basin were used to calibrate a non-linear regression model that predicted the combined crop coefficient (KcKs) as a function of the ratio of seasonal precipitation (P) to potential evapotranspiration (Ep). Crops included sorghum, pulses (mung bean, chickpea, soybean, pigeonpea) and oilseeds (safflower and sunflower). Ep was calculated with the Penman–Monteith equation using net radiation derived from two methods: (1) a surface radiation budget calculated from satellite imagery (EpSRB) and (2) empirical equations that use data from meteorological stations (EpGBE). The model of Ks as a function P/Ep was combined with a gridded time series of precipitation (0.5° resolution, 1901–2000) and maps of EpSRB to define the probability distributions of P, P/Ep and Ks for sorghum at each 0.5° cell over the basin. Sorghum, a C4 crop, had higher Ea and Ks values than the C3 plants (oilseeds, pulses) when precipitation was low (P < 1 mm d−1) but lower maximum Ea rates (3.3–4.5 mm d−1) compared with C3 crops (oilseeds and pulses, 4.3–4.9 mm d−1). The crop coefficient under adequate soil moisture (Kc) was higher than the FAO-56 crop coefficients by up to 56% for oilseeds and pulses. The seasonal soil moisture coefficient (Ks) for sorghum ranged from 1.0 under high rainfall (July–October) to 0.45 in dry seasons (November–March), showing strong soil moisture controls on Ea. EpSRB calculated at the lysimeter stations was 4–20% lower than EpGBE, with the largest difference in the dry season. Kc derived from EpSRB was only slightly (2–4%) higher than Kc derived from EpSRB, because the maximum Ea occurred during the monsoon when the differences between EpSRB and EpGBE were small. Approximately 20% of the basin area was expected to experience mild or greater soil moisture stress (Ks < 0.80) during the monsoon cropping season 1 year in every 2 years, while 70% of the basin experienced mild or greater stress 1 year in 10. The maps of soil moisture stress provide the basis for estimating the probability of drought and the benefits of supplemental irrigation.  相似文献   
32.
A 5 week experiment was carried out with juvenile yellowtail kingfish Seriola lalandi to investigate the interactive effects of water temperature (21, 24, or 27°C) and dissolved oxygen regime (normoxic vs. hypoxic) on the growth rate, feed intake and digestive enzyme activity of this species. Specific growth rate (SGR) was highest at 24°C, regardless of oxygen regime, but the SGRs of the fish exposed to hypoxia at 21, 24 and 27°C were 13%, 20% and 17% lower, respectively, than the SGRs recorded for the fish reared under normoxic conditions. The digestive enzyme activities (i.e. trypsin, lipase and α‐amylase) were influenced by temperature but did not appear to be affected by dissolved oxygen concentration. Information about the effects of water temperature and dissolved oxygen on feeding, growth and digestive capacity of juvenile yellowtail kingfish could contribute to improving feed management decisions for production of this fish species under different environmental conditions.  相似文献   
33.
The nutritional profile of dorsal and ventral portions of fillets from farmed yellowtail kingfish (YTK) (Seriola lalandi, Valenciennes, 1833) was assessed in winter and summer months to evaluate if there were differential distributions of proximate constituents, fatty acid composition and mineral content seasonally and through the dorso‐ventral axis. The proximate composition of YTK fillets varied between the two anatomical locations examined. In particular, a relatively large variation was observed in crude fat content, which decreased significantly from ventral to dorsal portions of the fillet and was inversely proportional to moisture and protein content. Higher crude fat content was also observed in the fish sampled in summer, compared to those sampled in winter. The omega 3/6 ratio remained constant between fillet portions but was significantly different between seasons (summer > winter). The index of nutritional quality for EPA and DHA was markedly different regarding to fillet portion and season (summer > winter, ventral > dorsal), and significant differences in the levels of potassium, phosphorus, magnesium and iron were also evident between the seasons examined. This study clearly shows differences in nutritional profiles of fillets from farmed YTK in South Australia relative to anatomical location and season. The increase in knowledge gained from this study may lead to improved farm management practices of YTK, which may extend to other commercially relevant species to enhance the production of premium farmed products.  相似文献   
34.
Pet dogs develop spontaneous cancers at a rate estimated to be five times higher than that of humans, providing a unique opportunity to study disease biology and evaluate novel therapeutic strategies in a model system that possesses an intact immune system and mirrors key aspects of human cancer biology. Despite decades of interest, effective utilization of pet dog cancers has been hindered by a limited repertoire of necessary cellular and molecular reagents for both in vitro and in vivo studies, as well as a dearth of information regarding the genomic landscape of these cancers. Recently, many of these critical gaps have been addressed through the generation of a highly annotated canine reference genome, the creation of several tools necessary for multi-omic analysis of canine tumours, and the development of a centralized repository for key genomic and associated clinical information from canine cancer patients, the Integrated Canine Data Commons. Together, these advances have catalysed multidisciplinary efforts designed to integrate the study of pet dog cancers more effectively into the translational continuum, with the ultimate goal of improving human outcomes. The current review summarizes this recent progress and provides a guide to resources and tools available for comparative study of pet dog cancers.  相似文献   
35.
Blood chemistry values for shovelnose and lake sturgeon   总被引:1,自引:0,他引:1  
Blood chemistry panels are commonly used for assessing the general health of vertebrate animals. Here, we present novel blood chemistry data for two North American sturgeon species, shovelnose sturgeon Scaphirhynchus platorynchus and lake sturgeon Acipenser fulvescens. Measurements were done using a portable chemistry analyzer (VetScan Analyzer; Abaxis). Among the plasma values measured (mean ± SD for shovelnose and lake sturgeon, respectively) were total proteins (3.7 ± 0.9 and 2.8 ± 0.4 g/dL), albumin (2.0 ± 0.5 and 1.1 ± 0.2 g/dL), globulin (1.7 ± 0.7 and 1.7 ± 0.3 g/dL), glucose (107 ± 46 and 62 ± 9.7 mg/dL), sodium (Na(+); 132 ± 3.6 and 150 ± 14 mEq/L), potassium (K(+); 3.5 ± 0.2 and 2.8 ± 1.7 mEq/L), phosphorus (10.4 ± 1.9 and 11.6 ± 3.6 mg/dL), and aspartate aminotransferase (AST; 676 ± 433 and 634 ± 234 IU/L). Higher values for total proteins, albumin, glucose, and Na(+) in shovelnose sturgeon than in lake sturgeon probably are the result of handling stress. In addition, the plasma of male shovelnose sturgeon had higher concentrations of AST, glucose, and globulin than did that of females, whereas the plasma of females had higher concentrations of albumin and K(+) than that of males. This study is the first to report blood chemistry data for shovelnose sturgeon. Robust blood chemistry databases can be used by aquaculturists and fish managers for monitoring sturgeon health.  相似文献   
36.
Xenogeneic plasmid DNA constructs have been developed and optimized for immunotherapies targeting cancer in both humans and dogs. Specifically, plasmid vectors containing the tumor antigen tyrosinase have demonstrated immunoreactivity and clinical benefit in the treatment of melanocytic tumors in these species. Overexpression of tyrosinase has also been noted in equine melanocytic tumors, supporting its role as a valid tumor antigen in the horse. Vaccination with plasmid constructs containing tyrosinase may thus have translational immunoreactivity in the treatment of equine melanomas. Here, we describe a methodology that is highly sensitive and specific for the detection of both humoral and cell-mediated immunoreactivity against tyrosinase in equine patients. These antigen-specific immunoassays are used to measure the humoral and cell-mediated responses in a cohort of horses vaccinated with xenogeneic plasmid DNA encoding human tyrosinase. Serum humoral responses were measured using standard enzyme-linked immunosorbent assay technique against the full-length recombinant human tyrosinase protein. Peripheral blood mononuclear cells were collected from vaccinated horses and stimulated with tyrosinase-specific peptides. Cell-mediated responses were then measured using a novel quantitative real-time-polymerase chain reaction technique to determine resultant interferon-γ expression. All horses developed significantly positive humoral and cell-mediated immune responses compared with their individual prevaccination values. No adverse reactions or signs of autoimmunity were detected. Vaccination with xenogeneic plasmid DNA expressing tyrosinase appears to elicit tumor antigen-specific reactivity and should be evaluated in a larger cohort of horses with melanocytic tumors.  相似文献   
37.
This article provides a brief overview of the process of outcomes assessment and examples of its application in professional health science education. The article is intended to provide a background for other articles in this issue describing ongoing activities in outcomes assessment in veterinary education and for programs considering developing a plan. The focus is on health professions other than veterinary medicine. The paper is not intended to be a comprehensive review of outcomes assessment; rather, it provides examples and models that may help clarify the outcomes assessment movement and identify trends in health care education.  相似文献   
38.
The efficacy of two systemically administered drugs for the treatment of equine joint injuries was assessed in a randomized blinded trial using the chemically induced equine carpitis model previously used to determine the dose and efficacy of both products. After a 10-day acclimation period, carpitis was induced by intracarpal injection of Complete Freund's Adjuvant (CFA) in twenty mature horses free of clinical and radiographic evidence of synovitis or DJD. Five days after model induction, the horses were stratified based on lameness evaluation and randomly assigned to 2 groups of 10 horses each.Parameters evaluated included lameness score, maximum range of carpal flexion, carpal circumference, stride length, and synovial fluid protein. These parameters were measured prior to model induction, 5 days after model induction (immediately prior to initial treatment) and once weekly for 6 weeks. Radiographs of the carpus were taken prior to model induction and 6 weeks. after treatment began. Treatment began 5 days after model induction. One group of 10 horses received 40 mg sodium hyaluronate by intravenous injection weekly for 3 weeks and the other group of 10 horses received intramuscular injections of 500 mg PSGAG every 4 days for 7 treatments.Both treatment groups showed significant improvement from pretreatment baseline values (based upon percent recovery to normal pre-model induction values) for lameness score, stride length and maximum carpal flexion (p<0.05) at each post treatment evaluation. The PSGAG treated group had significant improvement in synovial fluid protein at post treatment weeks 2 and 3. The improvement (percent recovery) in the PSGAG treated group was significantly (p<0.05) better than that of the intravenous sodium hyaluronate treated group for stride and flexion at post treatment weeks 1 through 6, for lameness score at post treatment weeks 1 through 3 and for carpal circumference at post treatment week 4.Both intravenous sodium hyaluronate and intramuscular PSGAG induced significant improvement in clinical lameness parameters; intramuscular PSGAG yielded consistently better results in this experimental model.  相似文献   
39.
40.
The use and efficacy of continuous rate infusion (CRI) of regular insulin intravenously for the treatment of feline diabetic ketoacidosis was retrospectively evaluated. The study focused on the rate of glucose decline, time to resolution of inappetence, time to long-term injectable insulin, and length of hospital stay. Review of medical records from 2009 to 2011 identified 10 cases that met the inclusion criteria. Six cats were existing diabetics, 3 of whom had recent insulin changes. Five cats had concurrent diseases. The mean time to long-term injectable insulin was 55 hours. The mean length of hospitalization was 3.8 days. Five cats survived to discharge. In 5 patients, an insulin CRI permitted a short hospital stay and transition to long-term injectable insulin. Many cats with diabetic ketosis or diabetic ketoacidosis are prior diabetics with concurrent disease and/or a history of recent insulin changes.  相似文献   
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