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排序方式: 共有727条查询结果,搜索用时 31 毫秒
721.
Oomah BD Tiger N Olson M Balasubramanian P 《Plant foods for human nutrition (Dordrecht, Netherlands)》2006,61(2):91-97
Eight lupin (Lupinus angustifolius L.) genotypes grown at four locations in south central Alberta in 2004 were evaluated for variability in phenolic constituents and antioxidant activity measured by a photochemiluminescence assay. Genotype was the main source of variation for content of phenolic compounds and antioxidant activities. Phenolic compounds in genotypes varied minimally from 11.9 to 14.7 mg catechin equivalent and 4.15 to 4.95 mg rutin equivalent g(-1) lupin for total phenolic and flavonoid contents, respectively. Lupin genotypes exhibited weak antioxidant activity based on water-soluble substances (ACW) of 0.54 to 1.07 micromole Trolox equivalent antioxidant capacities (TEAC)/g with lag time ranging from 70 to 153 s and an antioxidant index of 6.7 to 14.5 and 1.9 to 3.3 micromole TEAC/g based on measurements of lipid-soluble substances (ACL). Antioxidant activity of lupin genotypes was not related to phenolic contents of seeds. 相似文献
722.
INTRODUCTION: The International Physical Activity Questionnaire (IPAQ) was developed to measure health-related physical activity (PA) in populations. The short version of the IPAQ has been tested extensively and is now used in many international studies. The present study aimed to explore the validity characteristics of the long-version IPAQ. SUBJECTS AND METHODS: Forty-six voluntary healthy male and female subjects (age, mean +/- standard deviation: 40.7 +/- 10.3 years) participated in the study. PA indicators derived from the long, self-administered IPAQ were compared with data from an activity monitor and a PA log book for concurrent validity, and with aerobic fitness, body mass index (BMI) and percentage body fat for construct validity. RESULTS: Strong positive relationships were observed between the activity monitor data and the IPAQ data for total PA (rho = 0.55, P < 0.001) and vigorous PA (rho = 0.71, P < 0.001), but a weaker relationship for moderate PA (rho = 0.21, P = 0.051). Calculated MET-h day(-1) from the PA log book was significantly correlated with MET-h day(-1) from the IPAQ (rho = 0.67, P < 0.001). A weak correlation was observed between IPAQ data for total PA and both aerobic fitness (rho = 0.21, P = 0.051) and BMI (rho = 0.25, P = 0.009). No significant correlation was observed between percentage body fat and IPAQ variables. Bland-Altman analysis suggested that the inability of activity monitors to detect certain types of activities might introduce a source of error in criterion validation studies. CONCLUSIONS: The long, self-administered IPAQ questionnaire has acceptable validity when assessing levels and patterns of PA in healthy adults. 相似文献
723.
Olson EN 《Science (New York, N.Y.)》2006,313(5795):1922-1927
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726.
T L Grubb P D Constable G J Benson J H Foreman W O Olson J C Thurmon W J Tranquilli L E Davis 《American journal of veterinary research》1999,60(7):872-879
OBJECTIVES: To determine the most repeatable method for evaluating right ventricular relaxation rate in horses and to determine and compare effects of isoflurane or halothane with and without the added influence of intravenously administered calcium gluconate on right ventricular relaxation rates in horses. ANIMALS: 6 Thoroughbred horses from 2 to 4 years old. PROCEDURE: 6 models (2 for monoexponential decay with zero asymptote, 3 for monoexponential decay with variable asymptote, and 1 for biexponential decay) for determining right ventricular relaxation rate were assessed in conscious and anesthetized horses. The 2 methods yielding the most repeatable results then were used to determine right ventricular relaxation rates in horses anesthetized with isoflurane or halothane before, during, and after i.v. administration of calcium gluconate. Right ventricular pressure was measured, using a catheter-tip high-fidelity pressure transducer, and results were digitized at 500 Hz from minimum rate of change in ventricular pressure. RESULTS: 2 models that used monoexponential decay with zero asymptote repeatedly produced an estimate for relaxation rate and were used to analyze effects of anesthesia and calcium gluconate administration on relaxation rate. Isoflurane and halothane each prolonged right ventricular relaxation rate, with greater prolongation evident in halothane-anesthetized horses. Calcium gluconate attenuated the anesthesia-induced prolongation in right ventricular relaxation rate, with greater response obtained in isoflurane-anesthetized horses. CONCLUSIONS AND CLINICAL RELEVANCE: Right ventricular relaxation rate in horses is assessed best by use of a monoexponential decay model with zero asymptote and nonlinear regression. Intravenous administration of calcium gluconate to isoflurane-anesthetized horses best preserves myocardial relaxant function. 相似文献
727.
Integrating agroecology and landscape multifunctionality in Vermont: An evolving framework to evaluate the design of agroecosystems 总被引:3,自引:0,他引:3
Sarah Taylor Lovell S’ra DeSantis Meryl Breton Olson Hisashi C. Kominami Katlyn S. Morris 《Agricultural Systems》2010,103(5):327-184
Agroecosystems cover vast areas of land worldwide and are known to have a large impact on the environment, yet these highly modified landscapes are rarely considered as candidates for landscape design. While intentionally-designed agricultural landscapes could serve many different functions, few resources exist for evaluating the design of these complex landscapes, particularly at the scale of the whole-farm. The objective of this paper is to introduce an evolving framework for evaluating the design of agroecosystems based on a critical review of the literature on landscape multifunctionality and agroecology. We consider how agroecosystems might be designed to incorporate additional functions while adhering to agroecology principles for managing the landscape. The framework includes an assessment tool for evaluating farm design based on the extent of fine-scale land use features and their specific functions, to consider the present state of the farm, to plan for future conditions, or to compare alternative futures for the design of the farm. We apply this framework to two farms in Vermont that are recognized locally as successful, multifunctional landscapes. The Intervale Center, an agricultural landscape located within the city limits, serves as an incubator for new farm startups and provides unique cultural functions that benefit the local community. Butterworks Farm, a private operation producing organic yogurt and other food products, achieves important ecological functions through an integrated crop-livestock system. These farms and many others in Vermont serve as models of a framework that integrates landscape multifunctionality and agroecology in the design of the landscape. In the discussion section, we draw from the literature and our work to propose a set of important themes that might be considered for future research. 相似文献