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81.
82.
There is no reported method for the quantification of methylglyoxal in ruminal fluid. The method reported here is based on the conversion of methylglyoxal to 6-methylpterin, followed by quantification of the resulting pteridinic compound by fluormetric detection using liquid chromatography. Ruminal fluid was collected and preserved with 1 M HCl at -20 degrees C. Cation exchange prior to derivatization was used to eliminate possible interfering peaks. The detection limit of 0.125 microg/mL was calculated. The recoveries were >80%, and the coefficients of variation were <15%. This method has proven to be rugged and accurate for the detection of methylglyoxal concentration in ruminal fluid collected from cows fed diets deficient in degradable intake protein as a marker. Methylglyoxal is produced by ruminal bacteria in response to low nitrogen levels in the rumen. The ruminal methylglyoxal concentration has the potential to be a useful marker to assess ruminal nitrogen status to aid in more accurate diet formulation.  相似文献   
83.
The EPRI Tailored Collaboration State-of-the-Art Cooling Water Treatment Research Program has been initiated with several electric utility participants. Started in January 1995, the program will provide O&M cost reduction through improved cooling water system reliability and operation. This effort is discussed along with the objectives and goals, the participants and project timetable. The program will provide three (3) main results to the participating utilities: cost effective optimization of cooling water treatment, production of a new Cooling Water Treatment Manual and updating of two (2) EPRI software products — SEQUIL and COOLADD. A review of the specific objectives, project timetable and results to date will be presented.  相似文献   
84.
Two domestic shorthair cats were presented with anorexia and dehydration following ingestion of caramelized onions. Shared key findings from a CBC (ADVIA 2120), serum biochemistry, and urinalysis included a spurious, marked leukocytosis with discordant basophil (BASO) channel and peroxidase channel WBC counts, normal manual leukocyte counts, mild, non-regenerative anemia with discrepancies between automated and manual reticulocyte counts, an abundance of large Heinz bodies (HBs), and highly irregular scattergrams. Case 1 also demonstrated a markedly elevated mean corpuscular hemoglobin concentration (MCHC) and discrepancies between RBC hemoglobin indices. Spurious leukocyte results were confirmed through re-analysis of samples (including the acquisition of a new sample, use of an alternate analyzer (Sysmex XT-2000iV; Case 1 only), and evaluation of scattergrams and blood films (Cases 1 and 2). Repeatedly discrepant reticulocyte counts were also identified. In both cases, the erroneous BASO WBC counts, discrepancies in reticulocyte counts and RBC indices, and atypical scattergrams were interpreted to result from various effects of the HBs. These cases emphasize the importance of reviewing blood films, interpreting scattergrams, and the usefulness of duplicate methods for determining various measurands on hematology analyzers.  相似文献   
85.
Norovirus constitutes the most frequently identified infectious cause of disease outbreaks associated with untreated recreational water. When investigating outbreaks related to surface water, a One Health approach is insightful. Historically, there has been a focus on potential contamination of recreational water by bird droppings and a recent publication demonstrating human noroviruses in bird faeces suggested this should be investigated in future water‐related norovirus outbreaks. Here, we describe a One Health approach investigating a norovirus outbreak in a natural playground. On social media, a large amount of waterfowl were reported to defecate near these playground premises leading to speculations about their potential involvement. Surface water, as well as human and bird faecal specimens, was tested for human noroviruses. Norovirus was found to be the most likely cause of the outbreak but there was no evidence for transmission via waterfowl. Cases had become known on social media prior to notification to the public health service underscoring the potential of online media as an early warning system. In view of known risk factors, advice was given for future outbreak investigations and natural playground design.  相似文献   
86.
以厚皮甜瓜哈密瓜‘早皇后’品种(CucumismeloL.var.inodorusJacq.EarlyQueen)为试材,研究BTH、Amistar和KDF在甜瓜生长期处理对果实品质、产量、抗病性的影响。试验采用完全随机区组设计,在甜瓜生长期,施用药剂,对其对甜瓜品质等指标进行评价。结果表明:三种处理能够提高甜瓜果实可溶性固形物的含量,对单果重量、单位面积的产量、果实硬度影响较小。BTH处理使果形指数下降,KDF提高了果实整齐度。各处理改善了果实色泽,减少了果皮裂纹。Amistar、BTH和KDF处理使果实病害指数分别下降了14.9%和12.4%,1级果率提高5.9%和5.2%。各处理均降低了甜瓜叶部白粉病病害指数。BTH处理的细菌性角斑病的发病指数比对照降低了0.95。BTH处理对甜瓜品质、产量没有影响,降低了甜瓜果实病害,抑制了白粉病和细菌性角斑病的发展。  相似文献   
87.
Commercial products containing peracetic acid (PAA) are strong disinfectants with a wide spectrum of antimicrobial activity and have been suggested as potential therapeutic agents in aquaculture. The aim of this study was to compare the in vitro reduction of growth on two fish pathogens, Flavobacterium columnare and Saprolegnia parasitica, by seven commercial PAA‐containing products. Flavobacterium columnare was exposed to 1, 2, 4, 6, 8 and 10 mg L?1 PAA and S. parasitica was exposed to 0.5, 1, 2, 4, 6, 8 and 10 mg L?1 PAA in petri dishes for 24 h incubation. The reduction of growth was measured in comparison to a PAA‐free control. A reduction of the growth was observed for both pathogens with increasing PAA concentration. Hydrogen peroxide (H2O2) possibly has a role in the effectiveness of the products, since products with lower PAA concentrations had a higher concentration of H2O2. The commercial products with a low concentration of PAA and a low PAA:H2O2‐ratio were generally more effective against pathogens. The practical application of the products with low PAA concentration should be prioritized.  相似文献   
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89.
Field experiments were conducted during successive rainy seasons in 2006 in the Chau Thanh district of southern Vietnam to evaluate the effects of an inoculant plant growth promoter product called “BioGro” and N fertiliser rates on yield and N and P nutrition of rice. The results indicated that inoculation with BioGro, containing a pseudomonad, two bacilli and a soil yeast, significantly increased grain and straw yields and total N uptake in both seasons, as well as grain quality in terms of percentage N. Nitrogen fertilisation increased grain and straw yields as well as total N and P uptakes significantly in both cropping seasons. The estimated grain yield response to added N was quadratic in nature with and without added BioGro. In the first crop, BioGro out-yielded the control up to 90 kg urea N ha?1 whilst in the second season the beneficial effect of BioGro was observed up to 120 kg urea N ha?1, indicating either an interaction of the inoculant with higher yielding seasonal conditions or a cumulative effect of BioGro application. In the first season, the estimated N rate for maximum grain yield was 103 kg N ha?1 with BioGro while it was 143 kg N ha?1 without BioGro. The maximum estimated grain yields were 3.21 and 3.18 t ha?1 with and without BioGro, respectively. This information indicates that BioGro was able to save 40 kg N ha?1 with an additional rice yield of 30 kg ha?1 in the season. In the second rainy season, the estimated N rates for maximum grain yields were 94 and 97 kg N ha?1 with and without BioGro, respectively. The estimated maximum grain yields were 3.49 and 3.25 t ha?1 with and without BioGro, respectively. The two seasons’ combined results indicate that application of BioGro improved the efficiency of N use by rice significantly, saving 43 kg N ha?1 with an additional rice yield of 270 kg ha?1 in two consecutive seasons at the experimental site. The extra efficiency was shown by the fact that the same yield of rice was obtained with about 40 and 60 kg less fertiliser-N that the maximum yields with urea alone in the two successive harvests on the same plots.  相似文献   
90.
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