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951.
The aim of this study was to evaluate the long-term results of apicoectomy and retrograde endodontic treatment in 12 horses with apical cheek teeth infections. The affected apices were removed using a diamond bur mounted on a dental drill, and after pulp removal the root canals were filed with Hedstrøm files and then alternately flushed with sodium hypochlorite, hydrogen peroxide and alcohol. The pulp canals were dried and filled with endodontic cement and gutta-percha points. An undercut was made in the apical aspect of the root canals that were then sealed with self-curing glass ionomer cement.Follow up information was obtained 38–67 months following treatment and indicated that the treatment had been successful in 7/12 horses (58%), partially successful in 2 horses (17%) and unsuccessful in 3 (25%). With good case selection, apicoectomy can preserve a proportion of apically infected cheek teeth. The use of advanced imaging techniques and improved surgical techniques could increase the success rate.  相似文献   
952.
The effect of biotin supplementation on various foot lesions and hoof ceramide composition of toe (wall) and sole portions of hooves was studied in crossbred dairy cattle. Biotin supplementation was done for five months in 14 cattle at a farm and the other 14 animals kept as control. A significant decline was observed in heel erosions and sole avulsions along with total disappearance of white line fissures and double soles in the biotin supplemented cattle resulting in decrease in the overall disease score. Thin layer chromatographs of the hoof lipids revealed 11 types of ceramides in sole lipids and 6 types of ceramides in toe (wall) lipids. The ceramides were typed and identified according to their Rf values. A qualitative increase in the density of thin layer chromatographs of sole lipids was observed in biotin supplemented cattle whereas a non-significant difference in density of thin layer chromatographs of toe lipids was observed after supplementation of biotin.  相似文献   
953.
壳聚糖(chitosan)是甲壳素脱乙酰基后的产物,是天然多糖中唯一的碱性多糖,其自然资源丰富、安全无毒、不产生耐药性、生产成本低,具有改善动物生长性能、增强机体免疫力、调节脂肪代谢、抗菌抑菌和抗氧化等多种生物学功能,被认为是具有广泛开发前景的绿色添加剂。本文就壳聚糖生物学特性、生理功能及其在畜禽生产中的应用现状进行综述,以期为其在畜禽生产中的应用提供参考依据。  相似文献   
954.
Whole blood pharmacokinetics of intratumourally injected naked plasmid DNA coding for equine Interleukin 12 (IL-12) was assessed as a means of in vivo gene transfer in the treatment of melanoma in grey horses. The expression of induced interferon gamma (IFN-g) was evaluated in order to determine the pharmacodynamic properties of in vivo gene transduction. Seven grey horses bearing melanoma were injected intratumourally with 250 μg naked plasmid DNA coding for IL-12. Peripheral blood and biopsies from the injection site were taken at 13 time points until day 14 post injection (p.i.). Samples were analysed using quantitative real-time PCR. Plasmid DNA was quantified in blood samples and mRNA expression for IFN-g in tissue samples. Plasmid DNA showed fast elimination kinetics with more than 99 % of the plasmid disappearing within 36 hours. IFN-g expression increased quickly after IL-12 plasmid injection, but varied between individual horses. Intratumoural injection of plasmid DNA is a feasible method for inducing transgene expression in vivo. Biological activity of the transgene IL-12 was confirmed by measuring expression of IFN-g.  相似文献   
955.
This study investigated the long-term survival of a calf with cervical ectopia cordis that grew normally, became pregnant, and calved normally. The cow showed normal cardiac function and absence of peripheral circulation abnormalities. This paper documents antemortem characteristics of the affected cow.  相似文献   
956.
957.
Anion exchanger 1 (AE1) is the most abundant integral membrane protein in red cells and is essential for maintaining red cell mechanical stability. However, the mechanism for the assembly of AE1 into the membrane skeletal network remains unknown. Several mutants of murine AE1 tagged with an N-terminal enhanced green fluorescent protein (EGFP) and/or an extracellular FLAG epitope inserted adjacent to the N-glycosylation site were prepared, and their expression was analyzed in HEK293 or COS-1 cells by immunofluorescence microscopy, biotinylation, and deglycosylation. The EGFP- and FLAG-tagged AE1 mutant, as well as the wild-type AE1, exhibited cell surface expression in transfected cells and showed a rapid internalization that appeared to occur through the early endosome into the Golgi apparatus. Interestingly, the form of the protein with an endoglycosidase H (endo H)-sensitive N-glycan was the major component of EGFP-tagged and wild-type AE1. By contrast, the polypeptide with an endo H-resistant oligosaccharide was the predominant form of FLAG-tagged AE1. These data demonstrate that the processing of N-glycan is not a prerequisite to cell surface expression of AE1 and suggest that the FLAG tag insertion altered the accessibility of the N-glycan to enzymes in the Golgi which facilitate processing of oligosaccharides. Although whether this structural alteration would affect the structural and functional properties of AE1 remains unknown, cell surface expression and endocytic internalization of FLAG-tagged AE1 mutants indicate that these mutants are suitable for studying the mechanisms of the assembly and plasma membrane insertion of AE1.  相似文献   
958.
959.
960.
ObjectiveTo characterize the cardiorespiratory and electrocardiographic effects of the combined administration of phenylbutazone and romifidine.Study designProspective four-period, four-treatment, blinded, randomized, crossover trial.AnimalsFive, healthy, mixed breed horses.MethodsPrior to treatment administration, a catheter was introduced into the intra-thoracic cranial vena cava via the jugular vein and a subcutaneously located carotid artery was catheterised. All treatments were administered intravenously (IV) and consisted of saline placebo (PLC), phenylbutazone (PBZ, 4.4 mg kg?1) romifidine (ROM, 80 μg kg?1) and a combination of phenylbutazone (4.4 mg kg?1) and romifidine (80 μg kg?1). There was at least a 1 week washout period between treatments. Heart rate (HR), respiratory rate (fR), systolic (SAP), diastolic (DAP) and mean (MAP) arterial pressures and central venous pressure (CVP) were recorded for baseline (prior to drug administration) and at 5 minute intervals thereafter for 30 minutes. Electrocardiographic abnormalities were recorded. Data were analyzed by anova.ResultsFor the cardiovascular variables there were no statistically significant (p > 0.05) differences between horses treated with ROM and PBZ_ROM. Statistically significant (p < 0.05) differences only occurred between treatments with romifidine (ROM and PBZ_ROM) and without romifidine (PLC and PBZ). Within treatments, for ROM, changes over time were statistically significant (p < 0.05) for HR, SAP, DAP, MAP and CVP. For PBZ_ROM, changes over time were statistically significant (p < 0.05) for CVP. Sino-atrial and atrio-ventricular blocks occurred in horses treated with ROM and PBZ_ROM.Conclusions and clinical relevanceThe combined IV administration of phenylbutazone and romifidine had no statistically significant effect on cardiorespiratory variables. These limited data suggest no evidence why both agents should not be included in a preoperative medication protocol for healthy horses but do not exclude the possibility of interactions occurring in a larger population.  相似文献   
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