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81.
The influence of sward height at the time of slurry application on sward responses to slurry was investigated using perennial ryegrass ( Lolium perenne )/white clover ( Trifolium repens ) mini-swards under greenhouse conditions. Pig slurry, cattle slurry and a fertilizer control were applied either to: swards cut 1 d before slurry application to heights of 2, 4 or 8 cm (CH2, CH4 or CH8); or to swards cut to 4 cm with regrowth intervals of 1, 4 or 8 d before slurry application (RI1, RI4 and RI8). Scorch, smother and growth of marked clover stolons and grass tillers were monitored after slurry application. Dry-matter yields of both species were recorded over two harvests. Electrolyte leakage from leaves was used to assess leaf damage. Both slurries increased leakage, which was greatest from clover leaves, with biggest increases caused by pig slurry. Yield responses to slurry application varied with plant species and sward height. Reduced grass growth after slurry application to long swards (CH8, RI4, RI8) was probably caused by greater smother. In short swards (CH2), grass leaf growth was not depressed following slurry application but grass yields were reduced. Ammonia volatilization losses may have been greater in both long and short swards, contributing to yield reductions. Yield responses to slurry were greatest in swards cut to 4 cm, 1 d before application. 相似文献
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Hughes KJ Nicolson L Da Costa N Franklin SH Allen KJ Dunham SP 《Veterinary immunology and immunopathology》2011,140(1-2):82-89
Inflammatory airway disease (IAD) is a common disorder of performance horses and is associated with poor performance and accumulation of mucus and inflammatory cells in lower airway secretions. Horses with IAD frequently have increased relative counts of neutrophils in bronchoalveolar lavage fluid (BALF); less commonly relative counts of eosinophils and/or mast cells may be increased. The aetiopathogenesis of IAD is unknown and may involve innate and/or acquired immune responses to various factors including respirable dust constituents, micro-organisms, noxious gases and unconditioned air. The molecular pathways and role of the immune system in the pathogenesis of IAD remain poorly defined and it is unknown whether polarised T cell responses occur in the disease, as have been reported to occur in equine recurrent airway obstruction and asthma in humans. Elucidating cytokine responses that develop in horses with IAD may allow a greater understanding of the possible aetiopathological pathway(s) involved and could contribute to development of novel treatments. We compared the mRNA expression of tumour necrosis factor-alpha (TNF-α), interferon-gamma (IFN-γ), interleukin (IL)-1β, IL-2, IL-4, IL-8, IL-13, IL-17 and IL-23 in cell pellets extracted from BALF of horses with IAD (n=21) and horses free of respiratory tract disease (n=17). Horses with IAD had significantly increased levels of TNF-α, IL-1β and IL-23 mRNA; no significant differences in the other cytokine mRNAs were detected. The results of this study indicate that IAD of horses is associated with increased mRNA expression of pro-inflammatory cytokines in BALF cells, which may reflect stimulation of the innate immune responses to inhaled antigens. There was no evidence of a polarised T-cell cytokine response suggesting hypersensitivity responses may not be involved in the aetiopathogenesis of IAD. 相似文献
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Carlson JC Linz GM Ballweber LR Elmore SA Pettit SE Franklin AB 《Veterinary parasitology》2011,180(3-4):340-343
To investigate the relationship between European starlings and bovine coccidiosis we collected samples from European starlings, cattle feed bunks, cattle water troughs, and cattle feces within concentrated animal feeding operations (CAFOs). These samples were screened for coccidia spp. to investigate (i) the prevalence of coccidia in starlings using CAFOs; (ii) if there is a relationship between bovine coccidiosis and starling numbers; (iii) if coccidia contamination of cattle feed and water is related to the number of starlings observed on CAFOs. Coccidia belonging to the genus Eimeria were detected in cattle feces and one water sample but no Eimeria spp. were detected in European starlings or cattle feed. However, many European starling samples were positive for Isospora. Starling use of CAFOs did not appear to be associated with coccidia spp. shedding by cattle and there was no correlation between starling numbers and contamination of cattle feed and water, suggesting that starling do not contribute to the amplification and spread of Eimeria in CAFOs. 相似文献
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One hundred and fifty-six plant accessions, including susceptible checks, from the IR-1 collection were evaluated for resistance/immunity to bacterial ring rot (BRR). Each accession selected had been previously rated as highly resistant to BRR based on symptom expression but, in our tests, 57 of them yielded no plants which failed to produce symptoms. However, the remaining 99, represented by a total of 2589 inoculated plants, yielded 1000 plants which failed to produce BRR symptoms after eight weeks. Immunofluorescent antibody stain testing showed that 679 of the symptomless plants supported detectable numbers ofCorynebacterium sepedonicum cells. Comparison of root-inoculated and tuber-inoculated accessions showed that root-inoculations yielded significantly fewer symptomless and bacterial cell-free plants. No significant differences were found in BRR reactions of fiveSolanum spp. when inoculated with two different strains ofC. sepedonicum. Appreciable numbers of symptomless plants were obtained from inoculated progeny of crosses with resistant cultivars but none of those retested proved to be immune. 相似文献
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Tubers of Kennebec, Netted Gem and four seedlings treated with MH30 made acceptable chips after storage for 9 months at 55 F. After treatment with CIPC and storage at 46 F for nine months tubers of Kennebec and three seedlings made chips of acceptable colour; at 52 F Kennebec and two seedlings were acceptable. When reconditioned at 70 F for two weeks after storage at 40, 46 and 52 F, CIPC-treated samples of Kennebec made acceptable chips, plus one seedling from 40 F, two from 46 F and one from 52 F. 相似文献
90.
Daproma System AB 《林产工业》2000,27(3):44-45
全球农民每年都会面对一项挑战——在不致造成生态问题或额外开支的情况下,清除农田上过量的谷物残余物。 以在农田焚烧的方式来清除麦秸稻草的惯例在许多地方均引起关注。这是由于焚烧麦秸对泥土和环境均有损害,且会导致健康和交通问题。 小麦、大麦、稻谷、玉米和蔗渣等残余物的价值基本上均微不足道。Daproma可以将这些废料纤维转化成一种制造工业用优质刨花板和中密度纤维板的主要原材料。 一家装备Daproma设备的工厂可将一年生植物废料加工成作家具和柜子用的板材。而由于农业废料的成本远较木纤维的成本低,农业残余… 相似文献