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91.
The aim of the present study was to establish whether the inhibitory effect of fat feeding on fibre digestion has been underestimated due to the substitution of fat for corn starch. A high fat intake has been shown to lower total intestinal tract apparent digestibility of crude fibre in horses but, since fat was substituted for nonstructural carbohydrates, including starch, the specific effect of fat could not be ascertained. The possibility could not be excluded that starch also inhibits fibre digestibility, so that the fat effect observed earlier would have been underestimated. In this study, the intakes of iso-energetic amounts of soyabean oil, corn starch or glucose were compared as to fibre digestibility. Unlike starch, glucose is fully absorbed by the small intestine and, therefore, is not expected to influence fibre fermentation in the caecum and colon. Six trotters were fed rations high in soyabean oil (158 g/kg dry matter), corn starch (337 g/kg dry matter) or glucose (263 g/kg dry matter) according to a 3 x 3 Latin square design. Apparent crude fibre digestibility was similar for the rations with corn starch (mean +/- s.d., 70.7 +/- 3.06% of intake, n = 6) or glucose (71.0 +/- 1.90%), but was significantly depressed by fat feeding (56.5 +/- 7.65%). Similar observations were made for apparent digestibilities of neutral and acid detergent fibre and of cellulose. It was concluded that the addition of fat to the feed ration of horses has a specific inhibitory effect on fibre utilisation and, therefore, reduces the amount of energy provided by dietary fibre. 相似文献
92.
I. D. Wijnberg W. Ruitenbeek G. Jansen C. M. Westermann J. H. van der Kolk 《Equine Veterinary Education》2008,20(10):532-538
So far, the area of fat metabolism disturbances has been poorly explored in the horse but, as in man, deficiencies in the β‐oxidation of fatty acids (FAOX) and in carnitine metabolism or carnitine transport potentially can be a cause of myopathy. A 9‐year‐old Haflinger patient with recurrent rhabdomyolysis and 5 healthy horses of various breeds with a mean age of 16 ± 5.9 years were used as a comparison. Blood biochemical analysis revealed elevated aspartate amino transferase, lactate dehydrogenase and creatine kinase activities. Plasma vitamin E concentration was low and selenium was within the reference range. Quantitative electromyography was indicative of myopathy based on the short duration and low amplitude motor unit action potentials. Staining of muscle biopsies was suggestive for a myopathy based on a disturbance in fat catabolism. Carnitine, acylcarnitines, very‐long‐chain fatty acids and organic acids screening in blood and urine established no differences between these parameters in the patient and control horses. Even though this patient was negative on FAOX or carnitine disturbances, the potency of the applied methods seems large and indicates a potential diagnostic value. 相似文献
93.
Lyngstad TM Jansen PA Sindre H Jonassen CM Hjortaas MJ Johnsen S Brun E 《Preventive veterinary medicine》2008,84(3-4):213-227
Epidemiological information was summarized from 32 outbreaks of infectious salmon anaemia (ISA) on salmon farming sites in Norway in 2003–2005. Virus isolates from the outbreak sites were genotyped, and the genotyping was used to assess possible associations between outbreak sites due to adjacent location, sharing fish farming authorisation, sharing smolt suppliers or sharing broodfish origin of the fish. The ISA outbreaks were distributed along most of the Norwegian coast and showed a variable clinical picture. The virus genotypes clustered into three genogroups. Pairs of outbreak sites matched for adjacent location or registered under the same authorisation, all shared genogroup, which was a significantly higher number of corresponding genogroups than expected by chance. For outbreak sites sharing smolt suppliers, corresponding genogroups appeared in 7 out of 12 matched pairs, which was not significant. An evaluation of broodfish origin associated with genogroups did not support transmission linked to broodfish origin. In conclusion, genotyping of virus isolates from ISA outbreaks supports associations between adjacent outbreaks. This is consistent with horizontal transmission. The present study failed to find evidence for vertical transmission (patterns of genogroups related to smolt suppliers or broodfish companies were not identified). 相似文献
94.
This paper is a retrospective morphologic study of 7 young Boxer dogs, showing end-stage kidney lesions compatible with chronic pyelonephritis with severe segmental cortical atrophy and fibrosis, associated with chronic tubulointerstitial inflammation of varying degree. Azotemia was observed in 6 of the 7 cases. The gross kidney lesions were as follows: bilateral small kidneys with numerous segmental cortical scars causing depression of the renal cortical surface. Histologic examination revealed salient atrophy of nephrons, including paucity of glomeruli, glomerulocystic lesions, colloid-filled tubular microcysts, and a conspicuously increased occurrence of arteries with narrowed lumina caused by intimal thickening. These segmental abnormalities were accompanied by pronounced interstitial fibrosis. All but 1 dog showed salient tubulointerstitial lympho-plasmacytic infiltration, which in 3 cases also included diffuse infiltration of polymorphonuclear neutrophilic leukocyte (PMN)-cells and occurrence of tubular PMN-casts. Morphologic signs of abnormal metanephric differentiation (renal dysplasia) were observed in all cases in the form of atypical tubules or asynchronous nephronic development (immature glomeruli) or both. However, other morphologic primary dysplastic features were absent. Based on the morphologic features, it is concluded that the end-stage kidney disease in these young Boxer dogs was the result of chronic atrophic nonobstructive pyelonephritis, most probably caused by vesico-ureteral reflux, compatible with reflux nephropathy causing segmental hypoplasia (Ask-Upmark kidney) in man. It is proposed that atypical tubular epithelium in the form of adenomatoid proliferation of collecting duct epithelial cells should be considered an acquired compensatory lesion, rather than the result of disorganized metanephric development. 相似文献
95.
Noel M. Lacerna II Cydee Marie V. Ramones Jose Miguel D. Robes Myra Ruth D. Picart Jortan O. Tun Bailey W. Miller Margo G. Haygood Eric W. Schmidt Lilibeth A. Salvador-Reyes Gisela P. Concepcion 《Marine drugs》2020,18(12)
The bioactivity-guided purification of the culture broth of the shipworm endosymbiont Teredinibacter turnerae strain 991H.S.0a.06 yielded a new fatty acid, turneroic acid (1), and two previously described oxylipins (2–3). Turneroic acid (1) is an 18-carbon fatty acid decorated by a hydroxy group and an epoxide ring. Compounds 1–3 inhibited bacterial biofilm formation in Staphylococcus epidermidis, while only 3 showed antimicrobial activity against planktonic S. epidermidis. Comparison of the bioactivity of 1–3 with structurally related compounds indicated the importance of the epoxide moiety for selective and potent biofilm inhibition. 相似文献
96.
97.
Selectively working cation exchangers (® Lewatit OC 1029, OC 1030 and OC 1034, Bayer AG, Leverkusen) are very effective for the immobilization of ions of heavy metals (Zn2+, Cu2+, Pb2+). Applied at the calculated doses in a soil and/or substrate contaminated with ions of heavy metals, these cation exchangers withdraw the contaminants from the existing equilibrium system, which results in a neutralization of the fraction of the undesired phytotoxic identities. This method not only offers many possibilities in common peat and leaf mould soils, but gives a guarantee for plant-production in contaminated autochthonous areas and heterochthonous substrates. Ornamental plants and nursery trees developed well, especially in a terminated emission atmosphere, even in very strongly contaminated soils. 相似文献
98.
Experimental evidence is produced to justify abandoning the practice of subdividing Costridium botulinum Type C into type Calpha and Cbeta. 相似文献
99.
100.