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91.
92.
Marco?Costanigro Oana?Deselnicu Dawn?Thilmany?McFaddenEmail author 《Agriculture and Human Values》2016,33(3):597-609
This article examines quantitatively the determinants of purchase decisions based on corporate social responsibility (CSR), adopting a hierarchical conceptual model of decision making where the key factors are personal concern, information availability and financial considerations. We use best–worst methods to assess consumer priorities (personal concern) for CSR activities in milk production; and elicit consumer interpretation of four labels (organic, Validus, Colorado Proud and rBST free) in terms of CSR and other outcomes (information availability). We then elicit willingness to pay (WTP) for the labels (financial considerations), and estimate regression models to determine how predictive each label perceptual profile is of WTP for milk. Animal welfare and sustainable agricultural practices are the most important activities, and milk labels do convey CSR-related messages. With the exception of the pair animal welfare-Validus, the link between CSR messages and WTP is tenuous. The discussion emphasizes the central role of each label’s perceptual profile in triggering product differentiation among consumers. 相似文献
93.
Addiction profoundly alters motivational circuits so that drugs become powerful reinforcers of behavior. The interoceptive system continuously updates homeostatic and emotional information that are important elements in motivational decisions. We tested the idea that interoceptive information is essential in drug craving and in the behavioral signs of malaise. We inactivated the primary interoceptive cortex in amphetamine-experienced rats, which prevented the urge to seek amphetamine in a place preference task. Interoceptive insula inactivation also blunted the signs of malaise induced by acute lithium administration. Drug-seeking and malaise both induced Fos expression, a marker of neuronal activation, in the insula. We conclude that the insular cortex is a key structure in the perception of bodily needs that provides direction to motivated behaviors. 相似文献
94.
The possibility of arbitrarily "adding" and "subtracting" single photons to and from a light field may give access to a complete engineering of quantum states and to fundamental quantum phenomena. We experimentally implemented simple alternated sequences of photon creation and annihilation on a thermal field and used quantum tomography to verify the peculiar character of the resulting light states. In particular, as the final states depend on the order in which the two actions are performed, we directly observed the noncommutativity of the creation and annihilation operators, one of the cardinal concepts of quantum mechanics, at the basis of the quantum behavior of light. These results represent a step toward the full quantum control of a field and may provide new resources for quantum information protocols. 相似文献
95.
Perry SJ Baillie GS Kohout TA McPhee I Magiera MM Ang KL Miller WE McLean AJ Conti M Houslay MD Lefkowitz RJ 《Science (New York, N.Y.)》2002,298(5594):834-836
Catecholamines signal through the beta2-adrenergic receptor by promoting production of the second messenger adenosine 3',5'-monophosphate (cAMP). The magnitude of this signal is restricted by desensitization of the receptors through their binding to beta-arrestins and by cAMP degradation by phosphodiesterase (PDE) enzymes. We show that beta-arrestins coordinate both processes by recruiting PDEs to activated beta2-adrenergic receptors in the plasma membrane of mammalian cells. In doing so, the beta-arrestins limit activation of membrane-associated cAMP-activated protein kinase by simultaneously slowing the rate of cAMP production through receptor desensitization and increasing the rate of its degradation at the membrane. 相似文献
96.
André S. Nakatani Marco A. Nogueira Admilton G. Oliveira José P. Sousa 《Soil biology & biochemistry》2011,43(1):106-114
The application of tannery sludge to soils is a form of recycling; however, few studies have examined the impacts of this practice on soil microbial properties. We studied effects of two applications (2006 and 2007) of tannery sludge (with a low chromium content) on the structure of the bacterial community and on the microbial activity of soils. We fertilized an agricultural area in Rolândia, Paraná state, Brazil with different doses of sludge based on total N content, which ranged from 0 to 1200 kg N ha−1. Sludge remained on the soil surface for three months before being plowed. Soils were sampled seven times during the experiment. Bacterial community structure, assessed by denaturing gradient gel electrophoresis (DGGE), was modified by the application of tannery sludge. Soon after the first application, there was clear separation between the bacterial communities in different treatments, such that each dose of sludge was associated with a specific community. These differences remained until 300 days after application and also after the second sludge application, but 666 days after the beginning of the experiment no differences were found in the bacterial communities of the lowest doses and the control. The principal response curve (PRC) analysis showed that the first sludge application strongly stimulated biological activity even 300 days after application. The second application also stimulated activity, but at a lower magnitude and for a shorter time, given that 260 days after the second application there was no difference in biological activity among treatments. PRC also showed that the properties most influenced by the application of tannery sludge were enzymatic activities related to N cycling (asparaginase and urease). The redundancy analysis (RDA) showed that tannery sludge’s influence on microbial activity is mainly related to increases in inorganic N and soil pH. Results showed that changes in the structure of the bacterial community in the studied soils were directly related to changes of their biological activity. 相似文献
97.
Pascucci I Capobianco Dondona A Cammà C Marcacci M Di Domenico M Lelli R Scacchia M Jago M Khaiseb S Hager AL Tjipura-Zaire G Caporale V 《Journal of zoo and wildlife medicine》2011,42(4):634-640
A capture operation to ascertain health status in free-ranging buffaloes from six different areas in the Caprivi Strip in the northeast corner of Namibia was conducted in October 2009. Basic information on the ticks and tick-borne pathogens normally found in wildlife from this area are scarce. The objective of this study was to assess the host status of African buffaloes, Syncerus caffer, for ixodid ticks and two selected tick-borne pathogens in the Caprivi Strip, a key area bordering Angola, Zambia, Botswana, and Zimbabwe. Four different tick species have been identified among the 233 collected specimens, and, of 95 tested buffaloes, 54 (57%) were positive for Theileria parva, whereas only 3 (3%) showed evidence of being infected with Ehrlichia ruminantium. 相似文献
98.
99.
Lamastra L Ferrari F Fait G Greco L Kennedy SH Capri E Trevisan M 《Pest management science》2011,67(11):1439-1445
BACKGROUND: 1,3‐Dichloropropene (1,3‐D, CAS No. 542‐75‐6) is a broad‐spectrum soil fumigant used to control numerous species of soilborne plant‐parasitic nematodes. 1,3‐D consists of two isomers, (Z)‐ and (E)‐1,3‐D. There are a number of low‐level chlorinated compounds that could potentially be produced as a part of the 1,3‐D manufacturing process. 1,3‐D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3‐D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty‐five wells were monitored in five Italian regions characterised by historical and existing use of 1,3‐D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 µg L?1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)‐1,3‐D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. Copyright © 2011 Society of Chemical Industry 相似文献
100.
Otmar Spring Thines Marco Stefanie Wolf Reinhard Zipper 《European journal of plant pathology / European Foundation for Plant Pathology》2011,131(3):519-527
Sequencing of partial cox2 (part of the mitochondrial cytochrome-c-oxydase (COX) gene) was performed with samples from the oomycete genus Pustula, the white blister rusts of Asteraceae and related families. Sequence comparison uncovered several single nucleotide polymorphisms
(SNPs) between P. spinulosa and host specific strains of Pustula isolated from Senecio vulgaris, Tragopogon pratensis and cultivated sunflower, Helianthus annuus. Based on these differences, specific primers were designed for PCR-based detection of white blister rust strains pathogenic
to sunflower. The specificity of the primers was confirmed by cross testing with DNA from various oomycetes occurring in the
same locality. The limit of detection for DNA of P. helianthicola was 10 pg. This allowed detection with DNA from single sporangia and single oospores. The PCR-based experiments allowed detection
of the presence of sunflower white blister rust in soil samples from fields on which infected plants had been cultivated several
months before. Moreover, the molecular tools were successfully applied to trace the pathogen in asymptomatic tissue of infected
plants, demonstrating the systemic nature of Pustula on sunflower. 相似文献