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OBJECTIVE: This study employed a multilevel design to test the contribution of individual, social and environmental factors to mediating socio-economic status (SES) inequalities in fruit and vegetable consumption among women. DESIGN: A cross-sectional survey was linked with objective environmental data. SETTING: A community sample involving 45 neighbourhoods. SUBJECTS: In total, 1347 women from 45 neighbourhoods provided survey data on their SES (highest education level), nutrition knowledge, health considerations related to food purchasing, and social support for healthy eating. These data were linked with objective environmental data on the density of supermarkets and fruit and vegetable outlets in local neighbourhoods. RESULTS: Multilevel modelling showed that individual and social factors partly mediated, but did not completely explain, SES variations in fruit and vegetable consumption. Store density did not mediate the relationship of SES with fruit or vegetable consumption. CONCLUSIONS: Nutrition promotion interventions should focus on enhancing nutrition knowledge and health considerations underlying food purchasing in order to promote healthy eating, particularly among those who are socio-economically disadvantaged. Further investigation is required to identify additional potential mediators of SES-diet relationships, particularly at the environmental level. 相似文献
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F. Binet L. Fayolle M. Pussard J. J. Crawford S. J. Traina O. H. Tuovinen 《Biology and Fertility of Soils》1998,27(1):79-84
The stimulatory effect of earthworms (Lumbricus terrestris L.) on soil microbial activity was studied under microcosm-controlled conditions. The hypothesis was tested that microbial
stimulation observed in the presence of a soil invertebrate would be due to the utilization of additional nutritive substances
(secretion and excretion products) that it provides. Changes in microbial activity were monitored by measuring simultaneously
CO2 release and protozoan population density. The increase in CO2 released in the presence of earthworms was found to result from both earthworm respiration and enhanced microbial respiration.
The stimulation of microbial activity was confirmed by a significant increase in protozoan population density, which was 3–19
times greater in the presence of earthworms. The respiratory rate of L. terrestris was estimated to be 53 μl O2 g–1 h–1. Earthworm respiration significantly correlated with individual earthworm weight, but there was no correlation between the
increase in microbial respiration and earthworm weight. This finding does not support the hypothesis given above that enhanced
microbial respiration is due to utilization of earthworm excreta. A new hypothesis that relationships between microbial activity
and earthworms are not based on trophic links alone but also on catalytic mechanisms is proposed and discussed.
Received: 26 August 1997 相似文献
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R P Crawford L G Adams B E Richardson 《American journal of veterinary research》1990,51(11):1837-1840
Yearling heifers were given SC injections of 10(8) (n = 40), 10(9) (n = 44), or 10(10) (n = 44) colony-forming units of Brucella abortus strain 19 (S19). The proportion of heifers with positive serologic test results at 1 month following vaccination increased as the dose of S19 increased. These proportions decreased with time, and all heifers had negative card, rivanol, and complement fixation test results within 4 months. Positive ELISA results persisted beyond 4 months in all three S19 dose groups; however, all heifers were ELISA-negative within 9 months after vaccination. Comparable lymphocyte transformation activity was stimulated by S19 dose of 10(9) or 10(10) and approximately half of the heifers in both groups had a positive stimulation index at 9 months. Immunity of the pregnant heifers was challenged 9 months after vaccination with 10(7) B abortus strain 2308 as follows: diluent controls (n = 69); 10(8) B abortus S19 (n = 40); 10(9) B abortus S19 (n = 39); and 10(10) B abortus S19 (n = 39). Tissue specimens from heifers were obtained at parturition and necropsy for culturing of B abortus. The proportion of heifers that developed brucellosis, ie, had positive culture results, increased as gestation days at challenge exposure increased. The effect of gestational age was controlled in the analysis using logistic regression. The relative risk of brucellosis was reduced to 0.38, 0.15, and 0.06 for B abortus S19 doses of 10(8), 10(9), and 10(10), respectively, compared with diluent controls at 1.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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K N MacLellan D G MacDonald W H Crawford 《The Canadian veterinary journal. La revue veterinaire canadienne》1997,38(4):226-228
A 4-month-old colt with stage I flexural deformity of the distal interphalangeal joint was diagnosed as having a type IV nondisplaced fracture of the extensor process of the 3rd phalanx. An inferior check ligament desmotomy and internal fixation of the fracture were performed. Favorable long-term results for internal fixation of extensor process fractures are presented. 相似文献
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M Crawford 《Science (New York, N.Y.)》1986,232(4746):15-16
Increasing opposition to field tests of genetically altered organisms is causing the biotechnology industry to look to some form of government regulation as a way to calm the public's fears. Industry leaders are concerned that future developments will be subject to costly legal delays unless an efficient regulatory system is in place, although neither the federal government nor industry has been able to determine what standards are needed or what classes of products should be regulated. The two biotechnology trade associations have begun to work on their positions, regulatory legislation has been introduced in Congress, and the roles of the Environmental Protection Agency and the Department of Agriculture are about to be defined. There is a divergence of opinion about federally-supported intermediate test facilities, which some industry spokesmen believe would be unnecessary. 相似文献