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Objectives To investigate the use of unguided bronchoalveolar lavage techniques in dogs without fibreoptic bronchoscopy, using an adapted single vascular catheter and a double-lumen catheter made from two single vascular catheters.
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 106 /L was calculated from 57 clinically and histologically normal dogs. The major residual effects of the technique were localised pulmonary oedema, and alveolar distension with collapse and congestion of distant parenchyma. Thoracic radiographs revealed increased lung opacity for at least up to 7 h after the procedure.
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献
Animals Sixty-nine dogs were examined with the single-catheter technique and 110 dogs with the double-catheter technique.
Design A prospective study.
Procedure Sixty-nine and 220 samples, collected with the single catheter and the double catheter respectively, were examined cytologically Lungs of 69 dogs were examined grossly and histologically. Radiographic examination was performed on 11 dogs.
Results The double-catheter technique produced samples with significantly higher cellularity (P < 0.01) and fewer red blood cells (P < 0.01) than the single-catheter technique. Repeat samples collected with a double catheter were not significantly different (P > 0.01) in any value. A reference range for nucleated cell counts of 62 to 1210 – 10
Conclusions The cellularity of the bronchoalveolar lavage fluid obtained was adequate and sufficient fluid was retrieved when the single catheter was located in a proper position. However, the double catheter obtained better samples more quickly and easily, with less damage to the respiratory tract. 相似文献
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Organic debris extracted from wheatfield soils was found to be significantly more infective following 2–3 yr continuous wheat than after the fifth successive crop. Plots with added nitrogen yielded more infective debris than those without. Short periods of contact with decline soil or its suspension, reduced infection of wheat roots by Gaeumannomyces when they were subsequently grown in non-decline soil. Hyphae emerging from previously infected root pieces or culture inocula showed a positive growth response to wheat roots or their exudates. This response was negatively correlated to the distance between root and inoculum. In the presence of decline soil, hyphal response was significantly reduced. This reduction can be related to the decreased infectivity of decline soil and may help to explain take-all decline. 相似文献
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A field strain of Cooperia oncophora resistant to oxfendazole was isolated from a commercial cattle rearing property in Waikato, New Zealand. Resistance to oxfendazole was assessed by means of a faecal egg count depression test and an in vitro egg hatch test. This is the first documented case of anthelmintic resistance in Cooperia spp. and the first report of anthelmintic resistance in cattle in New Zealand. 相似文献
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Martin A Stapanian Vaughn L Paragamian Charles P Madenjian James R Jackson Jyrki Lappalainen Matthew J Evenson & Matthew D Neufeld 《Fish and Fisheries》2010,11(1):34-56
Although burbot ( Lota lota Gadidae) are widespread and abundant throughout much of their natural range, there are many populations that have been extirpated, endangered or are in serious decline. Due in part to the species' lack of popularity as a game and commercial fish, few regions consider burbot in management plans. We review the worldwide population status of burbot and synthesize reasons why some burbot populations are endangered or declining, some burbot populations have recovered and some burbot populations do not recover despite management measures. Burbot have been extirpated in much of Western Europe and the United Kingdom and are threatened or endangered in much of North America and Eurasia. Pollution and habitat change, particularly the effects of dams, appear to be the main causes for declines in riverine burbot populations. Pollution and the adverse effects of invasive species appear to be the main reasons for declines in lacustrine populations. Warmer water temperatures, due either to discharge from dams or climate change, have been noted in declining burbot populations at the southern extent of their range. Currently, fishing pressure does not appear to be limiting burbot populations world-wide. We suggest mitigation measures for burbot population recovery, particularly those impacted by dams and invasive species. 相似文献
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Immunotherapy to prevent recurrence of clinical signs of atopic dermatitis (AD) is based on intradermal or serological tests that assist in identifying allergen-specific immunoglobulin E hypersensitivities. Unfortunately, the results of such tests can be negatively influenced by several factors, which include the age of the patients, the season of testing and the administration of anti-allergic drugs. Screening to predict when these expensive tests will be useful would benefit owners of dogs with AD. The objectives of this study were to determine whether a point-of-care allergen-specific immunodot assay (Allercept E-Screen, Heska Corp., Ft Collins, CO, USA) could predict results of either intradermal or Allercept full panel serological tests in atopic dogs. Thirty dogs living in the south-eastern USA were diagnosed with AD in accordance with current standards. Allergen-specific intradermal, serological and E-Screen tests were performed in all subjects. For flea, house dust mite and pollen allergens altogether, results of the E-Screen assay agreed with those of intradermal and serological tests in 26/30 dogs (87%) and 25/30 dogs (83%), respectively. In this group of dogs, the probabilities of obtaining intradermal or serological tests positive for these allergens were 70 and 67%, respectively. If either skin or serum tests were performed only in dogs with positive E-Screen tests, the probability of obtaining positive results would be increased from 70 to 95% and from 67 to 90%, respectively. In this population of dogs with AD, results of the E-Screen point-of-care immunodot assay was found to often agree with those of allergen-specific intradermal or Allercept tests for selected allergen groups. 相似文献
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Kidney BA Haines DM Ellis JA Burnham ML Jackson ML 《American journal of veterinary research》2002,63(1):60-63
OBJECTIVE: To evaluate a group of vaccine site-associated sarcomas (VSS) for the presence of feline foamy virus (FeFV) DNA, using polymerase chain reaction (PCR) methods. SAMPLE POPULATION: 50 formalin-fixed paraffin-embedded (FFPE) tissue blocks from VSS of cats. PROCEDURE: DNA was extracted from FFPE sections of each tumor, and regions of the gag and pol genes of FeFV were amplified by use of PCR methods, using 1 primer set for each region. Sensitivity of the method was compared between fresh and FFPE cells, using mouse kidney tissue that was injected with FeFV-infected cultured cells and using agarose-cell pellets. Results-Feline foamy virus DNA was not detected in VSS tissues. Sensitivity of the method was 10 times greater in fresh versus FFPE mouse tissues. Sensitivity of the method in fresh FeFV-infected cultured cells versus FFPE agarose-cell pellets was equal when fixation was 24 or 48 hours and 10 times greater when fixation was 72 hours or 1 week. CONCLUSIONS AND CLINICAL RELEVANCE: A PCR-based method can be successfully applied to FFPE tissues for FeFV DNA detection. Results suggest there is no direct FeFV involvement in the pathogenesis of VSS in cats. 相似文献