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191.
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193.
The metabolic origins of equine hyperlipaemia were investigated by analysing the concentration and composition of plasma lipoproteins in 18 ponies with the condition. The mean concentrations of cholesterol, triglyceride and very low density lipoproteins (VLDL) were increased by 4-, 52- and 19-fold, respectively, compared with a control group of 18 healthy ponies. These increases were due to the appearance of a buoyant VLDL fraction (VLDL1) not present in healthy ponies. The mean diameter of VLDL1 particles was 44% greater than control VLDL, and the particles were enriched in triglyceride and free cholesterol and depleted of cholesteryl esters, phospholipid and protein. The apolipoprotein (apo) B-100 content of VLDL1 was reduced and the ratio of apoB-100 to apoB-48 particles was 1:1, compared with 2:1 in control VLDL. The VLDL1 was also enriched in apoE, but had normal complements of apoC-II and apoC-III. The conventional VLDL (called VLDL2), LDL and HDL fractions were moderately enriched with triglyceride, and HDL contained increased amounts of apoE, apoC-II and apoC-III. The activities of lipoprotein lipase and hepatic lipase, the enzymes responsible for the catabolism of VLDL and their remnants, were increased by 2- and 3-fold, respectively, in response to the increased concentrations of their substrates. The composition of VLDL1 suggested that the liver was maximising the secretion of triglyceride by producing larger number of VLDL particles that accommodated a greater mass of triglyceride by having apoB-48 rather than apoB-100 as their structural protein. Plasma free fatty acid (FFA) concentrations were elevated in 17 of the 18 ponies, suggesting that increased FFA flux might be the stimulus for hepatic triglyceride synthesis and VLDL secretion. We conclude that overproduction, rather than defective catabolism, of VLDL was the cause of the hyperlipidaemia and that lipid lowering agents which reduce VLDL synthesis, by decreasing adipose lipolysis and FFA flux, are candidates for the management of hyperlipaemia. 相似文献
194.
Theoretical comparisons for quantitativetrait loci (QTL) mapping properties wereconducted among simulated recombinantinbred (RI) populations developed bysingle-hill (SH), complete bulk, and singleseed descent (SSD) procedures by MonteCarlo simulations based on variouspopulation sizes, heritabilities, and QTLeffects. Our simulations includedestimation of QTL effects, QTL positions,and statistical testing power in the RIpopulations by comparing the estimates withpreset values. The simulation resultsshowed that the single hill (SH) bulk andsingle seed descent RI populations weregenerally not significantly different withrespect to quality of estimated QTL effectsand positions. Furthermore, when each RIpopulation had 150 lines, each couldprovide desirable properties for QTLmapping. The results implied that a SH RIpopulation consisting of 75 or moreF2-derived families with two lines perfamily (corresponding population size of150 or above) was appropriate for QTLmapping and was not significantly differentthan a SSD RI population of 150. Thus, theSH method could be used to develop largenumbers of RI lines for achieving betterresults in QTL mapping. Simulations alsoshowed that there was no significantdifference between means using SH methodswith 10 and 100 fruits per family. However, RI populations developed by thecomplete bulk method where F2identities are lost were not suitable forQTL mapping. 相似文献
195.
Immunophysiological activity of supramammary lymph nodes of the ewe during the very early phase of staphylococcal mastitis 总被引:1,自引:0,他引:1
Efferent mammary lymph was collected from lactating ewes which were unimmunised (controls) or immunised during pregnancy with two doses of an attenuated live Staphylococcus aureus vaccine either in the hindlimb ("directly primed' supramammary nodes) or in the brisket ("indirectly primed' supramammary nodes). Mammary lymph was also collected from unimmunised animals in which the supramammary nodes had been extirpated several months before. Ewes in which the supramammary nodes had been directly primed by staphylococcal vaccination before challenge had a significantly greater output of IgM- and IgG2-containing cells in lymph and higher concentrations of IgG1 and IgG2 antibody against S aureus surface antigens than did other groups. Lymphadenectomised ewes had fewer leucocytes in mammary lymph but a much higher proportion of neutrophils than other ewes, indicating that afferent mammary lymph has an unusually high number of neutrophils and most of these cells are filtered out in the supramammary lymph nodes under normal circumstances. The results indicated that most of the leucocytes in efferent lymph were derived from the supramammary nodes. After induction of experimental staphylococcal mastitis there was a rapid drop in leucocyte output in lymph within one to four hours after infection; the data indicated that events within the supramammary nodes were responsible for this phenomenon. The output of immunoglobulin-containing cells was reduced during this phase. No significant increases in output of lymphoblasts, immunoglobulin-containing cells or specific antibody occurred during the six hours immediately following infection. 相似文献
196.
Infection of six guinea pigs with up to 100 third-stage larvae of Elaphostrongylus cervi produced clinical signs of severe weight loss and ataxia or death in five. These signs occurred approximately eighty days after the larvae had been given per os. Single female E. cervi sub-adults were recovered from four affected animals and both a male and female E. cervi from one animal. Individual worms were found at the base of the brain against the internal surface of the dura mater. Histological and haematological parameters differed significantly between infected and control animals. 相似文献
197.
198.
Parker A. Watson Heather D. Alexander Jonathan D. Moczygemba 《Strength and Conditioning Journal》2019,72(2):275-282
Shrub encroachment into grasslands is a worldwide phenomenon with no signs of abating and numerous ecological consequences. In South Texas, honey mesquite (Prosopis glandulosa Torr.) and huisache (Vachellia farnesiana [L.] Wight & Arn.) are two shrubs encroaching into coastal prairies, reducing cover of the dominant native grass, gulf cordgrass (Spartina spartinae [Trin.] Merr. ex Hitchc.), and decreasing habitat for the endangered Aplomado Falcon (Falco femoralis), which requires grasslands or savannas for survival. To determine the best management approach for deterring shrub encroachment and restoring native grasslands, the US Fish and Wildlife Service used several shrub removal techniques within coastal prairies of the Bahía Grande Wetland Complex of the Laguna Atascosa National Wildlife Refuge, a core site for Aplomado Falcon reintroductions. Here, we assess native grass recovery over a 2-yr period in response to these shrub removal methods (mechanical plus prescribed fire and/or herbicide treatments) and degree of shrub encroachment before treatment. In general, areas with high levels of shrub encroachment before treatment had the highest amount of bare ground and lowest grass cover immediately following an initial mechanical treatment; this legacy effect persisted throughout the study irrespective of shrub removal treatment. Regardless of degree of shrub encroachment before treatment, grasses in areas treated with either mechanical or mechanical followed by herbicide methods recovered the slowest, likely due to residual woody material that hindered seed germination. Herbicide treatment following mechanical removal or mechanical removal plus fire effectively hindered shrub regrowth. Overall, mechanical treatment followed by prescribed fire and then herbicide application most effectively promoted grass recovery while hindering shrub regrowth. These findings suggest that grassland recovery following shrub encroachment into South Texas coastal prairies may be promoted through the application of shrub removal methods that combine mechanical, fire, and herbicide treatments. 相似文献
199.
K. Gray L. G. Alexander R. Staunton A. Colyer A. Watson A. J. Fascetti 《Journal of animal physiology and animal nutrition》2016,100(3):532-536
Low circulating taurine concentrations may be a risk factor for dilated cardiomyopathy (DCM) in dogs. Circulating taurine is typically measured in the clinic 4–5 h after feeding, largely because the impact of later sampling is not known. The objective of this study was to measure taurine in the blood during a 48‐h fast in 12 healthy adult Labrador Retrievers to refine sampling methodology for determination of taurine status. Plasma and whole blood (WB) taurine concentrations did not fall to levels indicative of clinical deficiency throughout fasting; WB was the more reliable indicator of taurine status. This study shows that blood samples can be taken for assessment of taurine status any time up to 48 h after ingestion of a meal in healthy adult dogs. 相似文献
200.
Prothrombin time and activated partial thromboplastin time using a point‐of‐care analyser (Abaxis VSpro®) in Bennett's wallabies (Macropus rufogriseus)
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BN Nevitt SK Chinnadurai MK Watson JN Langan MJ Adkesson 《Australian veterinary journal》2016,94(10):384-386
There are few reports of coagulation times in marsupial species. Blood samples collected from 14 Bennett's wallabies (Macropus rufogriseus) under anaesthesia during routine health assessments were analysed for prothrombin time (PT) and activated partial thromboplastin time (aPTT) using a point‐of‐care analyser (POC) (Abaxis VSPro®). The wallabies had an aPTT mean of 78.09 s and median of 78.1 s. The PT for all wallabies was greater than 35 s, exceeding the longest time measured on the POC. Although PT was significantly longer, aPTT was similar to the manufacturer's domestic canine reference range. 相似文献