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61.
López A Sims DE Ablett RF Skinner RE Léger LW Lariviere CM Jamieson LA Martínez-Burnes J Zawadzka GG 《American journal of veterinary research》1999,60(12):1558-1561
OBJECTIVE: To determine the acute anti-inflammatory effects of topically applied emu oil. ANIMALS: 96 male CD-1 mice assigned randomly to 4 groups, each comprising 24 mice. PROCEDURE: To induce auricular inflammation, 50 microl of a solution comprising 10 microl of croton oil dissolved in 1 ml of acetone was applied to the inner surface of the left auricle (pinna). One hour later, 3 or 5 microl of emu oil (low- and high-dose groups, respectively) or 5 microl of porcine oil (oil-control) was applied to the left pinna. Control mice remained untreated. Six mice per group were euthanatized 3, 6, 12, and 24 hours after induction of inflammation. Specimens of auricular tissue (ear plugs) were obtained, using a 6-mm biopsy punch. Magnitude of swelling was calculated as the weight difference between left (inflamed) and right (noninflamed) ear plugs; degree of edema was determined as the difference between wet and dry weights of the left ear plug. RESULTS: Magnitude of swelling was significantly reduced at 6 and 12 hours in mice treated with emu or porcine oil, compared with controls. The greatest reduction in swelling was detected in the high-dose emu group at 6 hours. Compared with controls, degree of edema was significantly reduced at 6 hours only in the high-dose group, whereas by 12 hours, all groups treated with oils had significantly less edema than controls. At 24 hours, magnitude of swelling and degree of edema did not differ among groups. CONCLUSION: Topically applied emu oil significantly reduced severity of acute auricular inflammation induced by croton oil in mice. 相似文献
62.
Skinner MA Keen DL Parlane NA Hamel KL Yates GF Buddle BM 《Research in veterinary science》2005,78(3):1-236
Possums are a wildlife vector of bovine tuberculosis in New Zealand. Vaccination of possums with BCG is being considered as a measure to control the spread of bovine tuberculosis to cattle and deer. Delivery via oral bait is feasible but BCG is degraded in the stomach. The aim was to determine whether ranitidine (Zantac) would reduce gastric acidity and enhance the efficacy of intragastrically administered BCG. A dose of 75 mg reduced gastric acidity for at least 4 h. Thus, possums were vaccinated intragastrically with BCG after receiving 75 mg ranitidine or ranitidine or BCG alone, as controls, before challenge with virulent Mycobacterium bovis. Proliferative responses of blood lymphocytes to M. bovis antigens after vaccination were significantly higher in possums given ranitidine/BCG compared to controls and seven weeks after challenge they had significantly lower lung weights and spleen bacterial counts than ranitidine alone controls. Vaccination with BCG alone only gave a reduction in loss in body weight. Agents that reduce gastric acidity may be useful in formulating BCG for oral bait delivery to wildlife for vaccination against bovine tuberculosis. 相似文献
63.
Effects of respacing on young Sitka spruce crops 总被引:1,自引:0,他引:1
64.
Chromosomes from cultured fibroblasts of two southern African ground squirrel species, Xerus inauris (2n = 38) and X. princeps (2n = 38), were compared using G-banding, C-banding and silver nitrate staining for the detection of NORs (nucleolar organizer regions). The karyoptypes of the two species, whose taxonomic status is the subject of some uncertainty, are largely identical except for a subtle heterochromatic difference which affects a single autosomal chromosome pair in X. inauris. The species specificity of this marker in their zone of contact indicates an absence of gene flow between these taxa and gives credence to the recognition of X. inauris and X. princeps as two biologically distinct species. 相似文献
65.
Neodymium (Nd) isotopic data show consistent patterns in the sources of sedimentary rocks in North America at a continental scale. Between 600 and 450 million years ago (Ma), ancient continental shield sources dominated. Around 450 Ma, detritus from the Caledonian-Appalachian mountains overwhelmed sediment from all older sources, and is documented over large areas of the southern, western, and northern margins of North America. This material continued to dominate the sediment supply until about 150 Ma, probably due to cannibalistic recycling of sedimentary rocks formed earlier. Around 150 Ma, the rising western Cordillera delivered new and different detritus to the sedimentary system. 相似文献
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Summary Each row was weighed separately in 34 sugar-cane variety trials harvested from 1973 to 1976. The efficiency of weighing only the middle row(s) compared with the whole plot was estimated by calculating coefficients of variation and theoretical gains from selection.It was not efficient to weigh only the middle row in trials with 3-row plots. Gain from selection for true yield (that is, yield in the absence of competition from other varieties) was reduced by 7% and the coefficient of variation increased by 4%, this representing an increase of about 33% in the variability of the trials.It was efficient to weigh only the middle two rows of 4-row plots, especially for trials on commercial farms. This gave a 2% increase in gain from selection and the coefficient of variation was increased by only 0.9%. It reduces the weighing time and amount of cane weighed, minimizing the delay to commercial harvesting while trials are being weighed.On Experiment Stations where land is a limiting factor, the most efficient method is to continue the present practice of planting 3-row plots and weighing the whole plots. 相似文献
70.
JB Siqueira E Oba RO Pinho SEF Guimarães TM Neto JD Guimarães 《Reproduction in domestic animals》2014,49(5):851-857
The objective of this work was to verify that mothers classified as super precocious (M1) and precocious (M2) produce more precocious bulls than females classified as normal (M3). This study included 21 186 animals with an average age of 21.29 ± 1.77 months that underwent a breeding soundness evaluation from 1999 to 2008. Of these animals, 2019, 6059 and 13 108 were offspring of M1, M2 and M3 females, respectively. In the breeding soundness examination, the animals were classified as sound for reproduction, sound under a natural mating regime, unsound for reproduction and discarded. To compare the averages obtained for each category of mother within the individual breeding soundness classes, a chi‐square test with a 5% error probability was used, considering the effects of year and month of birth and farm. For the three classes of mothers (M1, M2 and M3), 67.26, 67.22 and 64.16% of bull calves were considered sound for reproduction and 19.71, 19.46 and 21.90% were considered unsound for reproduction, respectively. There was no difference in the frequency of animals that were sound for reproduction under the natural breeding regime between the three classes of mothers (8.87, 9.31 and 9.19%, respectively). There was a difference between the numbers of precocious and normal females that were discarded, with frequencies of 4.01 and 4.75%, respectively (p < 0.05). There were differences in year and month of birth and farm between super precocious and precocious cows in relation to the breeding soundness classification of the animals. It was concluded that the bull offspring of super precocious and precocious cows presented a higher percentage of approval in the breeding soundness examination than the bull offspring of normal cows, demonstrating that the selection for precocity of females has contributed to an increase in the sexual precocity of the herd in relation to the sexual maturity of bulls. 相似文献