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51.
A highly potent penicillin inactivator has been extracted from 7 strains of Staph. aureus (coagulase positive), all of which were naturally penicillin resistant. No such inhibitor was present in extracts of 7 penicillin sensitive strains of Staph. aureus.  相似文献   
52.
Benzocaine, an ester-type local anesthetic, was believed responsible for apparent methemoglobinemia in a cat. The cat was admitted with acute respiratory distress, vomiting, and collapse, which began 15 to 20 minutes after topical application of the drug. Treatment consisted of supportive therapy and intravenous administration of methylene blue. The respiratory rate improved within 5 to 10 minutes of methylene blue administration and continued over a period of 2 hours. Benzocaine-induced methemoglobinemia has been reported in man, dogs, and cats. This report supports the findings of others regarding the potential toxicity of topical ester-type local anesthetics.  相似文献   
53.
Endenburg  Sarah  Mitchell  Greg W.  Kirby  Patrick  Fahrig  Lenore  Pasher  Jon  Wilson  Scott 《Landscape Ecology》2019,34(10):2385-2399
Landscape Ecology - Agricultural expansion is a principal driver of biodiversity loss, but the impacts on community assembly in agro-ecosystems are less clear, especially across regional scales at...  相似文献   
54.
Two questionnaires were completed by a selection of farms in Great Britain during 2008 and 2009 to ascertain the role of the National Fallen Stock Company (NFSCo) in fallen livestock disposal, the current disposal methods used for fallen livestock and other animal by-products (ABPs), and factors determining use of a particular method. The results demonstrated a significant difference (P<0.001) in NFSCo membership in relation to geographical location and a significant difference (P<0.001) in disposal choice. Farmers' perceptions as to why they did or did not join NFSCo, and why they used particular disposal methods are discussed. Disposal methods of other ABPs (aborted fetuses/stillborn animals and placentas) demonstrated the illegal disposal of aborted fetuses/stillborn animals (19.5 per cent of respondents) and placentas (57.6 per cent of respondents). Overall, 13.7 per cent of respondents used a variety of illegal disposal methods for fallen livestock carcases and other ABPs.  相似文献   
55.
AIMS: To determine current practices and attitudes towards vaccination of dogs and cats of veterinarians in New Zealand; the methods used for informing clients on which vaccines to use, and the preferred site for vaccination of cats.

METHODS: A postal questionnaire was sent to all 483 listed veterinary practices in New Zealand during February 2012. Some questions were specific to pet dogs, cats, or working farm dogs. Responses were categorised according to practice type and geographical region of the respondent. Factors associated with respondent recommendation of annual vaccination with modified live viral (MLV) vaccines were examined using logistic regression analysis. Vaccines that were considered to be essential for every animal were defined as core; those that may be recommended for animals whose location or lifestyle placed them at risk, were defined as non-core.

RESULTS: There were 204 useable returns, equivalent to a response rate of 42.2%, distributed across the country. Annual vaccination with MLV vaccines of dogs was recommended by 54/198 (27.3%) respondents, and of cats by 107/181 (59.1%) respondents. Factors associated with the recommendation of annual administration of MLV vaccines to dogs included being a companion animal practice, a desire for policies on vaccination to be left to individual clinics, and having one veterinarian in the practice. Administration of the final vaccination for puppies was recommended at ≥14 weeks old by 55/185 (29.7%) respondents, and for kittens at ≥13 weeks old by 42/183 (23%) respondents. Of respondents that administered MLV vaccines annually, 62/103 (60.2%) believed reducing the frequency of vaccination would reduce income, and 52/103 (50.5%) considered it would have a negative effect on animal health. Advice to enable clients to decide which non-core vaccines were administered was given by 181/199 (91%) respondents. Factors considered when recommending a vaccine included consideration of risk to individual patients (190/203; 93.6%), requirements of boarding kennels/catteries (165/203; 81.3%) and clinic vaccination policy (142/203; 70%). The preferred site for administering MLV vaccines to cats was the dorsal neck or inter-scapular region (137/198; 69.2%). Amongst respondents, 18 wanted disease surveillance information to allow for truly informed decisions to be made about vaccination.

CONCLUSIONS AND CLINICAL RELEVANCE: Veterinarians can now compare their own vaccination practices and attitudes with those of veterinarians nationally, and internationally. There is a need for national surveillance information and for continued education of the public and commercial kennel and cattery owners for optimal vaccination strategies to be developed.  相似文献   

56.
The growth performance and endocrine responses of male weaner pigs (3 to 8 weeks of age) was evaluated in two different environments (clean and dirty) and housing (single or groups of 10 pigs/pen) conditions. The dirty environment contained significantly elevated ammonia, carbon dioxide and dust levels compared with the clean environment. Pigs grew faster and consumed more feed in the clean environment and this was associated with reduced plasma cortisol concentrations compared with pigs in the dirty environment. Pigs housed in groups in the dirty environment had increased β-endorphin and decreased IGF-I concentrations compared to group housed pigs in the clean environment. Feed conversion efficiency did not differ due to environment or group housing. Plasma concentration of cortisol, β-endorphin, IGF-I and IGF-II did not differ between single and group housed pigs. Activity of the hypothalamic-pituitary-adrenal (HPA) axis was greater in response to environmental conditions than group housing, and this was associated with reduced growth in weaner pigs.  相似文献   
57.
58.

Objective

To compare the performance of an alfaxalone constant rate intravenous (IV) infusion versus a 3-step IV infusion, both following a loading dose, for the maintenance of a target plasma alfaxalone concentration of 7.6 mg L–1 (effective plasma alfaxalone concentration for immobility in 99% of the population) in cats.

Study design

Prospective randomized crossover study.

Animals

A group of six healthy, adult male neutered cats.

Methods

Catheters were placed in a jugular vein for blood sampling and in a medial saphenous vein for drug administration. An IV bolus of alfaxalone (2 mg kg–1) was administered, followed by either 0.2 mg kg?1 minute?1 for 240 minutes (single infusion; SI) or 0.4 mg kg?1 minute?1 for 10 minutes, then 0.3 mg kg?1 minute?1 for 30 minutes, and then 0.2 mg kg?1 minute?1 for 200 minutes (3-step infusion; 3-step). Plasma alfaxalone concentration was measured at six time points during the infusions. Measures of performance were calculated for each infusion regimen and compared using the paired Wilcoxon signed-rank test.

Results

Median (range) absolute performance error, divergence, median prediction error and wobble were 15 (8–19)%, ?8 (?12 to ?6)% hour?1, ?12 (?19 to ?7)% and 10 (8–19)%, respectively, in the SI treatment, and 6 (2–16)%, 0 (?13 to 2)% hour?1, 1 (?16 to 4)% and 4 (3–6)% respectively, in the 3-step treatment and were significantly smaller in the 3-step treatment than in the SI treatment.

Conclusion and clinical relevance

After IV administration of a bolus dose, a 3-step infusion regimen can better maintain stable plasma alfaxalone concentrations close to the target concentration than a single constant rate infusion.  相似文献   
59.
Genetically matched pluripotent embryonic stem (ES) cells generated via nuclear transfer or parthenogenesis (pES cells) are a potential source of histocompatible cells and tissues for transplantation. After parthenogenetic activation of murine oocytes and interruption of meiosis I or II, we isolated and genotyped pES cells and characterized those that carried the full complement of major histocompatibility complex (MHC) antigens of the oocyte donor. Differentiated tissues from these pES cells engrafted in immunocompetent MHC-matched mouse recipients, demonstrating that selected pES cells can serve as a source of histocompatible tissues for transplantation.  相似文献   
60.
In some regions of the world, where the bioavailability of selenium (Se) in soil is low and/or declining (e.g., due to use of high-sulfur fertilizers), there is increased risk of adverse affects on animals and human health. In recent years, increased research attention has focused on understanding the relationships between Se contents in foods and supplements and their nutritional benefits for animal and humans. The objective of this study was to use a species-unspecific isotope dilution and reverse phase ion pairing-inductively coupled plasma-mass spectrometry techniques for the identification and quantification of Se species in biofortified grains (i.e., wheat and triticale), flour, and wheat biscuits. The information on Se species was used to gain an understanding of the bioavailability of Se in biofortified and process-fortified wheat biscuits used in a clinical trail. The major Se species identified in biofortified and process-fortified samples were selenomethionine (76-85%) and selenomethionine selenoxide (51-60%), respectively. Total plasma Se concentrations in the biofortified Se exposure group were found to increase throughout the 6 month trial period (mean=122 microg L(-1) at 0 months to 194 microg L(-1) at 6 months). In contrast, the trial group exposed to process-fortified Se biscuits showed little increase in mean total Se plasma concentrations until 4 months of exposure (mean=122 microg L(-1) at 0 months to 140 microg L(-1) at 4 months) that remained constant until the end of the trial period (mean=140 microg L(-1) at 4 months to 138 microg L(-1) at 6 months). The difference in total Se plasma concentrations may be due to the presence and bioavailability of different Se species in biofortified and process-fortified biscuits. An understanding of Se speciation in foods enables better understanding of pathways and their potential benefits for animals and humans.  相似文献   
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