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81.
Tonya A. Lander Etienne K. Klein Solenn Stoeckel Stéphanie Mariette Brigitte Musch Sylvie Oddou-Muratorio 《Landscape Ecology》2013,28(9):1769-1783
Widespread ecosystem change has led to declines in species world-wide. The loss of pollinators in particular constitutes a problem for ecosystem function and crop production. Understanding how landscape change affects pollinator movement, effective pollen flow, and plant and pollinator survival is therefore a global priority. In this study we investigated patterns of effective pollen flow, using wild cherry tree (Prunus avium) progeny arrays, to address two questions in three case studies: Do land-use types present different resistances to pollinator movement? Which pollinator travel path best explains the pollination data (straight lines, weighted straight lines, least cost paths or pair-wise resistance)? Trees and progeny arrays were genotyped and effective pollen flow and pollinator movement were estimated using the spatially explicit mating model. We found that pollinators did modify their travel paths in response to land-use type and arrangement, but the travel path that best described pollinator movement and the resistance rank of the land uses depended on the type and size of land-use patches and the landscape context. We propose a novel theoretical framework rooted in behavioural ecology, the resource model, for interpreting pollinator behaviour in heterogeneous landscapes. We conclude by discussing the importance and practicality of conservation and management strategies in which native and non-native land-use types together provide functional habitat and support ecosystem services across economic landscapes. 相似文献
82.
Geert J. W. Janssen Arend Van Norel Brigitte Verkerk-Bakker Richard Janssen 《Potato Research》1995,38(4):353-362
Summary Various methods of screening for resistance to root-knot nematodes were compared and evaluated. Seedling populations ofSolanum spp., grown in clay pots and plastic tubes with silver sand and inoculated with juveniles ofMeloidogyne chitwoodi andM. hapla, showed large differences in the number of egg masses on roots 7 weeks after inoculation. The differences were reproducible
when re-testing was done with cuttings and plants from tubers. No resistance toMeloidogyne spp. was observed with ten potato cultivars when grown in clay pots, plastic tobes or closed containers. Plants from tubers
in growth pouches developed a large two-dimensional root system, and after inoculation with juveniles the infection process
could be observed over 8 weeks.
A method of infecting potato tuber tissue withMeloidogyne is described, using tuber slices in Petri dishes as a potential screening test for tuber resistance. 相似文献
83.
84.
Ameet Singh DVM DVSc Diplomate ACVS Brigitte A. Brisson DMV DVSc Diplomate ACVS Stephanie Nykamp DVM Diplomate ACVR 《Veterinary surgery : VS》2011,40(6):762-767
Objective: To (1) describe computed tomographic (CT) popliteal lymphangiography; (2) compare the number of thoracic duct (TD) branches detected by CT and by radiography after popliteal lymphangiography; and (3) to compare the number of branches detected after left and right popliteal lymphangiography. Study Design: Experimental study. Animals: Adult dogs (n=6). Methods: A randomly selected popliteal lymph node was percutaneously injected with 12 mL iodinated contrast medium through a 25‐g butterfly catheter over 4–5 minutes. Lateral and ventrodorsal (VD) thoracic radiograph projections and thoracic CT were performed. The procedure was repeated using the contralateral lymph node after a 48–72 hours washout period. Results: One dog had TD branches visible on CT but not on radiographs. A significantly greater number of TD branches were observed with CT popliteal lymphangiography compared with lateral and VD radiographic popliteal lymphangiography (P=.003 and P<.001, respectively). The number of visible TD branches observed between the 6th thoracic and 1st lumbar vertebrae were not significantly different in these dogs (P=.146). A significant difference in number of TD branches observed was not found after left or right popliteal lymph node injection (P=.097). Conclusions: CT popliteal lymphangiography consistently identified a greater number of TD branches when compared with radiographic popliteal lymphangiography. Injection of either popliteal lymph node resulted in the same number of TD branches being observed. 相似文献
85.
J. Barrat Marie Jos Barrat Monique Picard M. F. A. Aubert collaboration technique Y. Gerard Chantal Patron Josiane Ambert B atrice Quillou 《Comparative immunology, microbiology and infectious diseases》1988,11(3-4):207-214
Mouse inoculation test (MIT) is a highly sensitive test for rabies diagnosis but slow and expensive. To detect rabies virus an in vitro technique using Neuro 2a cell culture (CC) was compared with MIT in two laboratories.
In one laboratory, CC appeared to be on the whole more sensitive than MIT, nevertheless MIT was the only one to detect some positive samples. In the other laboratory, MIT was more sensitive. These results justify the use of CC for epidemiological diagnosis but emphasize the interest of MIT (the reference technique) for special cases. 相似文献
86.
Brigitte Moreau J Christophe Vié Philippe Cotellon Ingrund De Thoisy Annie Motard Christian P Raccurt 《Journal of zoo and wildlife medicine》2003,34(2):159-162
Individuals of two porcupine species (Coendou prehensilis and Coendou melanurus) were translocated during the flooding of a forest at a hydroelectric dam site in French Guiana. Blood samples were collected for 11 mo to determine hematologic and serum chemistry reference mean values and ranges and to look for blood parasites. Male C. prehensilis had significantly higher hemoglobin levels, packed cell volumes, and creatinine and potassium values than did females of the same species. Coendou prehensilis had significantly lower amylase levels but higher creatinine, calcium, lactate dehydrogenase, and gamma glutamyl transferase levels than C. melanurus. 相似文献
87.
Double-sandwich enzyme-linked immunosorbent assay for determination of Escherichia coli heat-labile porcine enterotoxins 总被引:1,自引:0,他引:1
A "double-sandwich" ELISA for the detection and measurement of a heat-labile enterotoxin produced by porcine enterotoxigenic strains of Escherichia coli (LTp) is described. In contrast with other heat-labile toxins, LTp did not bind to agarose gels and exhibited a very low affinity for GM1 in the classical GM1-ELISA technique. The similarity of LTp with cholera toxin was confirmed by immunoblotting. This property allowed the binding of LTp to rabbit IgG anti-cholera toxin antibodies (covalently linked to polystyrene plates) and sheep anti-cholera toxin serum. The immunocomplex was revealed by anti-sheep immunoglobulin antibodies conjugated with peroxidase. Application of the "double-sandwich" ELISA to the quantitation of toxin production by two strains, which differ only in the presence or the absence of the K88ab antigen, showed that the Ent+, K88+ strain produced significantly less toxin than the Ent+, K88- derivative. 相似文献
88.
Purchase C Picard J McDonald R Bisschop SP 《Journal of the South African Veterinary Association》2008,79(1):39-43
This study was undertaken to establish whether the Onderstepoort Biological Products Fowl Typhoid (OBPft) vaccine registered as an injectable vaccine was effective and safe when administered orally to commercial layers. Its efficacy and duration of protection were compared with application by intramuscular injection. Commercial brown layer hens were used as they were found to be highly susceptible to Salmonella gallinarum infections. In the vaccine safety trial birds were euthanased at timed intervals spanning 4 weeks postvaccination. Necropsies were performed and samples were taken and tested. No clinical signs or mortalities could be attributed to the OBPft vaccine nor could active shedding of the vaccine strain be detected. Slight pathological changes were noted with both routes of vaccination; however, these changes were transient, returning to normal within the observation period. The injected groups showed a better serological response with the rapid serum plate agglutination (RSPA) test than the orally vaccinated groups. In the duration of protection trial, birds were challenged at 3-8-week intervals post-vaccination. All unvaccinated birds died. Protection 8 and 16 weeks after vaccination was above 60 %,by 24 weeks after challenge, the vaccine protection was below 30 %. It was found that there was no significant difference (P < 0.05) in the protection offered by either the oral or injected route of vaccination with the OBPft vaccine. 相似文献
89.
Evaluation of a method to assess digitally recorded surgical skills of novice veterinary students 下载免费PDF全文
90.
Mathilde Bettembourg Audrey Dardou Alain Audebert Emilie Thomas Julien Frouin Emmanuel Guiderdoni Nourollah Ahmadi Christophe Perin Anne Dievart Brigitte Courtois 《Rice》2017,10(1):45