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21.
R J Seiler 《The Veterinary record》1979,105(10):226-228
The mathematical relationships between the sensitivity and specificity of screening tests and the proportion of animals which are positive to the test, but which have no visible lesions (NVL) at subsequent examination or necropsy, are outlined briefly. NVL reactors may be defined as a proportion of the total number of reactors to the test (reactor NVL per cent) or of the total number of animals tested (herd NVL per cent). Neither the herd nor reactor NVL per cent can provide valid estimates of the efficacy of any particular test, unless the precise prevalence of disease in the tested herd is determined. However under conditions of low or moderate prevalence specificity is approximately equal in magnitude to 100-herd NVL per cent but sensitivity cannot be reliably estimated from either the herd or reactor NVL per cent. 相似文献
22.
The serological response of pigs to Erysipelothrix rhusiopathiae inoculation was monitored by a gel diffusion precipitin test (GDPT) using a crude, serotype-specific, autoclaved antigen and an enzyme-linked immunosorbent assay (ELISA) using a heat-extracted, alcohol precipitated and molecular seived antigen previously shown to react with serum from pigs infected with serotypes 1 or 2. All pigs receiving 3 or 5 weekly intravenous inoculations of either a highly virulent (VRS 229) or a lowly virulent isolate (VRS 252) produced GDPT-reactive antibody within 3 weeks, but only 44% were still reactive at 8 to 9.5 weeks. The ELISA response was significantly higher in pigs inoculated with the highly virulent strain, and was similar in pigs receiving 3 or 5 doses of either strain. In a dose-response trial, after 3 doses of VRS 229, GDPT reactivity occurred earlier and was stronger in pigs given higher doses of E. rhusiopathiae, but the response peaked 3 to 5 weeks after the start of challenge and was short lived. GDPT reactivity correlated with dose, but not with the severity of arthritis. The ELISA demonstrated specific IgG antibody was present by 2 weeks, and persisted to at least 11 weeks. The ELISA reactivity was significantly higher in pigs with arthritis than in pigs that received low doses and were not arthritic. Within groups of pigs with arthritis a significant, dose dependent, linear ELISA response developed but did not correlate with the presence or degree of arthritis at slaughter. Non-arthritic pigs had similar low ELISA responses to uninoculated controls. 相似文献
23.
The shape of and proportions between the surface areas of the medial coronoid process (MCP) and the fovea of the radial head were determined in 88 juvenile dogs and 146 adult dogs grouped as giant, large, mid-sized, chondrodystrophic, or small dogs. Thereby, the longitudinal (length) and transverse (width) extension of the MCP and fovea of the radial head have been measured. Original values were used to describe changes of the parameters attributed to growth. Normalized values (i.e. values expected in case of a width of the fovea of the radial head of 20 mm) were used to determine potential differences between constitutional types. All original values increased during growth (P < 0.05) except for the width and length of the MCP in chondrodystrophic and small breeds. Normalized values revealed a proportional decrease in width and length of the MCP during growth (P < 0.05) compared with the radial head. In adults, the normalized MCP was widest in giant dogs followed by large, mid-sized, small, and chondrodystrophic breeds. The MCP was also longest in giant dogs but shortest in large and chondrodystrophic dogs with those of large dogs being significantly (P < 0.05) shorter than those in giant, mid-sized and small dogs. Present results suggest that a deficiency in length-growth of the MCP--which has been present especially in large dogs--results in smaller humeral contact areas and decreased weight-bearing capacity of the MCP. Because loading forces acting on the MCP increase with body weight, the condition noted in large dogs might increase the risk of fragmentation of the MCP in these. 相似文献
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26.
The computed tomographic “tree‐in‐bud” pattern: Characterization and comparison with radiographic and clinical findings in 36 cats 下载免费PDF全文
27.
JE Lupton ET Baker N Garfield GJ Massoth RA Feely JP Cowen RR Greene TA Rago 《Science (New York, N.Y.)》1998,280(5366):1052-1055
The migration and evolution of a deep ocean hydrothermal event plume were tracked with a neutrally buoyant RAFOS float. The float remained entrained in the plume for 60 days, and the plume vorticity was calculated directly from the anticyclonic motion of the float. Concentrations of suspended particles, particulate iron, and dissolved manganese in the plume did not decay significantly during the 60 days, which indicates that event plumes would be easily detectable a year after formation. 相似文献
28.
Magdalene J. Seiler Robert B. Aramant† Mathias W. Seeliger‡ Ragnheidur Bragadottir§ Melissa Mahoney¶ Kristina Narfstrom 《Veterinary ophthalmology》2009,12(3):158-169
Purpose To investigate whether sheets of fetal retinal allografts can integrate into the dystrophic Abyssinian cat retina with progressive rod cone degeneration.
Methods Fetal retinal sheets (cat gestational day 42), incubated with BDNF microspheres, were transplanted to the subretinal space of four cats at an early disease stage. Cats were studied by fundus examinations, bilateral full-field flash ERGs, and indocyanine green and fluorescein angiograms up to 4 months following surgery. E42 donor and transplanted eyes were analyzed by histology and immunohistochemistry for retinal markers.
Results Funduscopy and angiography showed good integration of the transplants in two of four cats, including extension of host blood vessels into the transplant and some scarring in the host. In these two, transplants were found in the subretinal space with laminated areas, with photoreceptor outer segments in normal contacts with the host retinal pigment epithelium. In some areas, transplants appeared to be well-integrated within the host neural retina. Neither of these two cats showed functional improvement in ERGs. In the other two cats, only remnants of donor tissue were left. Transplants stained for all investigated cellular markers. No PKC immunoreactivity was detected in the fetal donor retina at E42, but developed in the 4-month-old grafts.
Conclusions Fetal sheet transplants can integrate well within a degenerating cat retina and develop good lamination of photoreceptors. Functional improvement was not demonstrated by ERG in cats with well-laminated grafts. Transplants need to be further evaluated in cat host retinas with a more advanced retinal degeneration using longer follow-up times. 相似文献
Methods Fetal retinal sheets (cat gestational day 42), incubated with BDNF microspheres, were transplanted to the subretinal space of four cats at an early disease stage. Cats were studied by fundus examinations, bilateral full-field flash ERGs, and indocyanine green and fluorescein angiograms up to 4 months following surgery. E42 donor and transplanted eyes were analyzed by histology and immunohistochemistry for retinal markers.
Results Funduscopy and angiography showed good integration of the transplants in two of four cats, including extension of host blood vessels into the transplant and some scarring in the host. In these two, transplants were found in the subretinal space with laminated areas, with photoreceptor outer segments in normal contacts with the host retinal pigment epithelium. In some areas, transplants appeared to be well-integrated within the host neural retina. Neither of these two cats showed functional improvement in ERGs. In the other two cats, only remnants of donor tissue were left. Transplants stained for all investigated cellular markers. No PKC immunoreactivity was detected in the fetal donor retina at E42, but developed in the 4-month-old grafts.
Conclusions Fetal sheet transplants can integrate well within a degenerating cat retina and develop good lamination of photoreceptors. Functional improvement was not demonstrated by ERG in cats with well-laminated grafts. Transplants need to be further evaluated in cat host retinas with a more advanced retinal degeneration using longer follow-up times. 相似文献
29.
We conducted a 1-year greenhouse experiment to assess the impact of nutrient manipulations on seedling growth, biomass partitioning, and leaf gas exchange between two fast growing Pinus taeda clones that differed in growth efficiency. After 1 year we observed significant treatment and treatment by clone effects on growth, biomass partitioning, and gas exchange parameters. Fertilization increased total seedling biomass 18% primarily through an increase in foliage and coarse-roots. Clones did not differ in total seedling biomass, however, clone 85 produced more stem than clone 93 leading to 37% greater stem:leaf, while clone 93 maintained more branch biomass. The logging residue treatment increased stem:leaf by 30%, but had no effect on total biomass or partitioning. Differences in leaf morphology resulted in significantly greater canopy leaf area in clone 93 than clone 85. Increased foliar N concentration from fertilization had only minor effects on specific photosynthesis under saturating light (ASat), but lowered stomatal conductance (gs), transpiration (E), and internal to external CO2 concentration ratio (Ci/Ca) as well as improved water use efficiency (WUE) independently of genotype. When gas exchange data was scaled to the canopy level both genotypes achieved similar canopy level CO2 assimilation rates, but our data suggests they did this by different means. Although we did see a small effect of nutrient limitations in total canopy photosynthesis under saturating light (ACanopy), ASat, and total leaf area (TLA), our foliar N concentration ([N]) indicated that our level of logging residue incorporation did not cause [N] to decrease below sufficiency limits. From a practical standpoint, a better understanding of strategies for capturing and partition C may lead to better selection of clonal material, thereby, optimizing productivity. 相似文献
30.
Hanno Zielke Thomas-Benjamin Seiler Sabine Niebergall Erik Leist Markus Brinkmann Denise Spira Georg Streck Werner Brack Ute Feiler Thomas Braunbeck Henner Hollert 《Journal of Soils and Sediments》2011,11(2):352-363