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951.
OBJECTIVE: To compare efficacy and safety of paste formulations of firocoxib and phenylbutazone in horses with naturally occurring osteoarthritis. DESIGN: Randomized controlled clinical trial. ANIMALS: 253 client-owned horses with naturally occurring osteoarthritis. PROCEDURES: Horses were treated with firocoxib (0.1 mg/kg [0.045 mg/lb], PO, q 24 h) or phenylbutazone (4.4 mg/kg [2 mg/lb], PO, q 24 h) for 14 days. Physical examinations and lameness evaluations were performed prior to treatment and after 7 and 14 days. Clinical improvement was defined as a reduction of at least 1 lameness grade or a combined reduction of at least 3 points in scores for pain during manipulation or palpation, joint swelling, joint circumference, and range of motion. RESULTS: Proportion of horses clinically improved on day 14 for the firocoxib group (104/123 [84.6%]) was not significantly different from the proportion for the phenylbutazone group (103/119 [86.6%]). Proportion of horses that were improved on day 14 was significantly greater for horses treated with firocoxib than for horses treated with phenylbutazone with regard to score for pain on manipulation or palpation (P = 0.028), joint circumference score (P = 0.026), and range of motion score (P = 0.012), but not for overall lameness score or joint swelling score. No direct treatment-related adverse effects were detected during the study. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that overall clinical efficacy of a paste formulation of firocoxib in horses with naturally occurring osteoarthritis was comparable to efficacy of a paste formulation of phenylbutazone.  相似文献   
952.
953.
OBJECTIVE: To establish a safe and effective technique for the endoscopic examination and biopsy of snake lungs by use of a 2.7-mm rigid endoscope system. DESIGN: Clinical trial. ANIMALS: 17 adult ball pythons (Python regius). PROCEDURES: The right lung of each anesthetized snake was transcutaneously penetrated at a predetermined site. Endoscopic lung examination was objectively scored, and 3 lung biopsies were performed. Tissue samples were evaluated histologically for diagnostic quality. One year later, 11 of the 17 snakes again underwent pulmonoscopy and biopsy; specimens were placed in various fixatives to compare preservation quality. All 17 snakes were euthanatized and necropsied. RESULTS: No major anesthetic, surgical, or biopsy-associated complications were detected in any snake. In 16 of 17 pythons, ease of right lung entry was satisfactory to excellent, and views of the distal portion of the trachea; primary bronchus; intrapulmonary bronchus; cranial lung lobe; and faveolar, semisaccular, and saccular lung regions were considered excellent. In 1 snake, mild hemorrhage caused minor procedural difficulties. After 1 year, pulmonoscopy revealed healing of the previous transcutaneous lung entry and biopsy sites. Important procedure-induced abnormalities were not detected at necropsy. Diagnostic quality of specimens that were shaken from biopsy forceps into physiologic saline (0.9% NaCl) solution before fixation in 2% glutaraldehyde or neutral-buffered 10% formalin was considered good to excellent. CONCLUSIONS AND CLINICAL RELEVANCE: By use of a 2.7-mm rigid endoscope, lung examination and biopsy can be performed safely, swiftly, and with ease in ball pythons. Biopsy specimens obtained during this procedure are suitable for histologic examination.  相似文献   
954.
Methicillin-resistant Staphylococcus aureus (MRSA) colonization was not identified in any of 497 horses from Atlantic Canada. Methicillin-susceptible S. aureus (MSSA) was isolated from a subsample of 19/242 (7.9%) horses. Colonization with MSSA is relatively common in healthy horses in Atlantic Canada, but MRSA is currently rare or absent.  相似文献   
955.
We recently reported that blockade of the CD40-CD154 ligand interaction with the cross-reacting mouse anti-human CD154 antibody, 5c8, together with donor-specific transfusion led to enhanced but not completely successful engraftment in a canine model of DLA-identical marrow transplantation after 100cGy total body irradiation (TBI). In order to improve the transplantation outcomes, we sought to develop a canine-specific reagent. To that end, we fused the extracellular domain of the canine CD40 with a mouse IgG2a Fc tail and tested the immunosuppressive effectiveness of the fusion protein in mixed leukocyte reactions. The extracellular domain of canine CD40 was fused with the Fc portion of mouse IgG2a in a pcDNA3.1+vector. Dhfr-deficient CHO cells were co-transfected with the CD40-Ig vector and a dhfr-containing vector. Stable, high producing clones were selected under increasing methotrexate concentrations. The fusion protein was purified, tested in mixed leukocyte reactions, and its immunosuppressive effect compared to that of the anti-CD154 antibody 5c8. The transfected cell line produced a CD40-Ig dimer whose identity was confirmed by mass spectroscopy. The purified canine CD40-Ig blocked mixed leukocyte reactions at a concentration of 1nM, which was 10 times more effective than the anti-CD154 antibody. Canine CD40-Ig is more immunosuppressive than the anti-human CD154 antibody 5c8 in canine mixed leukocyte reactions and may be more effective in vivo in a model of marrow transplantation.  相似文献   
956.
Objective— To compare short‐ and long‐term outcome and complications of chest wall reconstruction in dogs using autogenous, prosthetic, and composite autogenous–prosthetic techniques. Study Design— Historical cohort. Animals— Dogs (n=44) with spontaneous tumors arising from or involving the chest wall. Methods— Medical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, intraoperative findings and complications, reconstruction technique (autogenous muscle flap, prosthetic mesh, or composite autogenous–prosthetic technique), and short‐ (≤14 days) and long‐term (>14 days) postoperative complications were determined from the medical records and telephone contact with owners and referring veterinarians. Associations between chest wall reconstruction technique and postoperative complications were tested with Cox proportional hazards. Results— Chest wall defects were reconstructed with autogenous muscle flaps (29 dogs), prosthetic mesh (3), and a composite technique of prosthetic mesh and either autogenous muscle or omental pedicle flap (12). Early postoperative complications were recorded in 8 dogs (18.2%) and included seroma (5) and pleural effusion and peripheral edema (3). One dog had a late complication (2.3%) with a mesh‐related infection 767 days postoperatively. Overall, complications occurred in 10.3% of autogenous, 25.0% of composite, and 66.7% of prosthetic reconstructions. Chest wall reconstruction with Marlex mesh alone was associated with a significantly increased risk of postoperative complications compared with autogenous reconstruction (P=.027). Reconstruction of sternal defects (3), 2 of which were performed with Marlex mesh alone, was associated with a significantly increased risk of complications compared with lateral chest wall reconstructions (P=.037). Conclusions— Large chest wall defects can be reconstructed with autogenous and composite techniques, but prosthetic mesh should be covered with well‐vascularized autogenous muscle or omentum to decrease the risk of postoperative complications. Sternal defects should be reconstructed with rigid techniques. Clinical Relevance— Chest wall reconstruction with autogenous muscle flaps or a combination of autogenous techniques with prosthetic mesh is associated with a low rate of infection and other complications.  相似文献   
957.
The role of contact parameters in a complex spatial simulation model of foot-and-mouth disease spread was determined by comparing predictions of number of infected premises, epidemic duration, and relative infection risk for different production sectors between a model that included the Full, heterogeneous (differing by production type) type-specific information about animal, vehicle and personnel movement between premises, and models that used partial and homogeneous (similar across production types) weighted-mean or proxy parameter sets for contacts between premises of all types. The model was run using a dataset of known premises locations in a three-county area in the Central Valley of California and categorized into 13 premises types and six production sectors.Results from models run with homogeneous contact parameters were always different from those obtained from the Full model, demonstrating that model predictions are affected by heterogeneity in contact parameters. Models simplified by using weighted-mean parameters predicted fewer infected premises. Models that were simplified by using medium dairy farm or large swine operation proxy parameters predicted longer epidemics with more infected premises, while those using small beef operation proxy parameters predicted shorter epidemics with fewer infected premises. Simplified-parameter models underestimated the impact on the economically important dairy sector, while overestimating the impact on beef and backyard operations. Results establish a need for heterogeneous, operation-specific contact parameters in complex stochastic simulation models that must be weighed against the cost of obtaining and coding premises type-specific contact information.  相似文献   
958.
If the prevalence of bovine spongiform encephalopathy (BSE) varies among cohorts within a population, stratified analysis of BSE surveillance data may allow identification of differences in BSE exposure that are important with respect to the design and evaluation of disease prevention and control measures. In low BSE prevalence populations, however, surveillance at levels that meet or exceed international guidelines may provide insufficient statistical power to distinguish prevalence levels among cohorts. Furthermore, overstratification to account for hypothetical variability in the population may inflate uncertainty in BSE risk estimates.  相似文献   
959.
The genome sequences of eight pigeon circoviruses (PiCV) were determined and compared with four previously published sequences. The viruses compared were from the USA, five European countries, China and Australia and included PiCVs from racing, feral, ornamental and meat pigeons and a Senegal dove (Streptopelia senegalensis). The 12 PiCV genomes, ranging from 2032 to 2040 nucleotides in length, displayed similar organizations. Pairwise comparisons showed that the genome nucleotide sequence identities ranged from 85.1% to 97.8% and that the amino acid identities of the putative replication associated (Rep) and putative capsid (Cap) proteins displayed ranges of 91.5-99.1% and 73.0-99.3%, respectively. Comparative analyses identified conserved nucleotide sequences within the Rep gene and 3' intergenic regions, which would be suitable for diagnostic PCR primers, and variable amino acid sequences within the capsid proteins, which should be considered when selecting virus isolates for vaccine development.  相似文献   
960.
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