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41.
ABSTRACT Managers and other stakeholders may rely on wildlife-related risk communication campaigns to prevent or reduce risks associated with human-wildlife conflict. The operating environment or the sphere of activity within which a campaign functions can influence a campaign's ability to achieve outcomes. Between 1 May 2005 and 30 October 2005, we studied human-black bear conflict in southeastern New York and the wildlife-related risk communication campaign, the New York NeighBEARhood Watch (NYNW). Based on the social amplification of risk framework, our goal was to determine whether mass media affected the operating environment of the campaign, and if so, identify the magnitude and direction of the effect. We used a self-administered mail survey (N = 2,800) in 4 southeastern New York, USA, towns to collect data about residents’ perceived black bear-related risks, bear-related behavior, and exposure to the NYNW. We also conducted a content analysis of mass media coverage about black bears. Exposure to the NYNW from newspapers was positively correlated (R = 0.39, P < 0.01) with respondents’ decreased acceptance of black bear-related risks. Our results showed a small social amplification of risk associated with black bears from exposure to mass media, specifically newspapers. Mass media can influence the operating environment of a wildlife-related risk communication campaign, including through amplification of risk perception. Characterizing the operating environment of campaigns is key to HWC-intervention planning, evaluation, and policy. Wildlife practitioners can consider media effects, as well as other biological and social factors, as potential influences on a campaign's operating environment and be aware that interaction effects may occur.  相似文献   
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The effects of some amino acid analogues (o-, m- and p-fluorophenylalanineand azetidine-2-carboxylic acid) on uptake of42K and 45Ca intothe roots and transport to the shoots of whole wheat and mungbean seedlings were measured. The effect of each analogue oneither K+ or Ca2+ movement could be placed into one of fourcategories: (1) No effect on either ion uptake or transport;(2) No effect on ion uptake, but a reduction in transport; (3)Similar reductions in ion uptake and transport; (4) A relativelygreater reduction in ion transport than in uptake. At leasttwo independent sites of protein involvement in ion movementwere required to account for all four types of analogue effectobserved; one site of protein involvement was probably at theplasmalemma of root cortex cells and the second site, involvinga protein that turned over more quickly, was within the stele.Some evidence was found that Ca2+ transport is a passive process.Light did not stimulate uptake. Key words: Triticum aestivum, Vigna radiata, Two pump hypothesis  相似文献   
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Spore Discharge in Deightoniella torulosa (Syd.) Ellis   总被引:1,自引:0,他引:1  
MEREDITH  D. S. 《Annals of botany》1961,25(3):271-278
Violent spore discharge in the Hyphomycete Deightoniella torulosais described. On drying, a negative pressure develops in thesolution inside the swollen head of the conidiophore. This causesthe thin wall at the top of the conidiophore to cave inwardsand to be brought into a state of tension. The sudden appearanceof a gas phase in the conidiophore head releases this tension,and the wall rapidly returns to its original rounded shape.The conidium, which is attached to the top of the conidiophore,is thus catapulted away. This appears to be the first recordof a gas phase being associated with violent spore dischargein a fungus.  相似文献   
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RNA and protein components of maize streak and cassava latent viruses   总被引:3,自引:0,他引:3  
Polyacrylamide gel electrophoresis indicated that maize streak (MSV) and cassava latent (CLV) viruses each contain one species of protein and two of RNA. The estimated protein mol. wt is 28000 for MSV and 34000 for CLV. The mol. wts obtained for the two RNA species using formamide-containing gels were the same for the two viruses: 17×108 and 1–3 × 106. It is suggested that the viruses have a two-part genome and that the tendency of their nucleoprotein particles to form pairs favours the delivery of complete genomes to sites of infection.  相似文献   
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In theory, one factor determining the rate and nature of the assembly of island biotas is the presence or absence of stepping stone islands, yet no field studies have demonstrated stepping stone function in practice. Krakatau, in Sunda Strait, is about equidistant from Java and Sumatra. Sebesi lies about half way between Krakatau and Sumatra, but no island intervenes between Krakatau and the nearest coast of Java. We assess the evidence that Sebesi has acted as an important stepping stone for Krakatau's recolonization since the devastating 1883 volcanic eruption. About a quarter of Krakatau's resident land birds, two-fifths of its reptiles, bats and land molluscs, and about two-thirds of its termites, pteridophytes, butterflies and spermatophytes are unknown on Sebesi, evidently having colonized without stepping stone involvement. Identifiable Sumatran taxa do not outnumber identifiable Javan ones on Krakatau, nor do historical distribution records indicate movement from Sebesi to Krakatau in animal groups. Krakatau's biota is not a subset of Sebesi's in predominantly anemochorous or thallassochorous plant groups, butterflies, reptiles or bats, and is only marginally so in termites. It is a subset in predominantly zoochorous spermatophyte groups, except Ficus species, and in birds and land molluscs. Comparison with a weaker stepping stone candidate, Panaitan, provides no evidence for a stepping stone role for Sebesi in butterflies or termites. We discuss the dispersal and establishment constraints on colonization by the groups involved, and conclude that, overall, Sebesi had little impact as a stepping stone. Instead, it is more probable that divergence of the environments of the two islands has led to an increasingly independent recolonization of Krakatau.  © 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 77 , 275–317.  相似文献   
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We compared the proportion of morphological variation accounted for by subspecies categories with the proportion encompassed by ecologically based categories in cutthroat trout ( Oncorhynchus clarkii ssp.), as a means of assessing the relative importance of each approach in identifying intraspecific diversity. We used linear and geometric morphometrics to compare measures of body shape, fin length, and head features between and within subspecies of cutthroat trout. Both categories accounted for a significant proportion of the variation between and within the subspecies; however, the larger proportion was explained by subspecific differences, with the greatest morphological divergence between coastal cutthroat trout ( Oncorhynchus clarkii clarkii ) and interior subspecies. Ecotypic categories within each subspecies also explained significant morphological differences: stream populations had longer fins and deeper, more robust bodies than lake populations. The largest ecotypic differences occurred between stream and lake populations of Yellowstone cutthroat trout ( Oncorhynchus clarkii bouvieri ). Given that many cutthroat trout subspecies are of conservation concern, our study offers a better understanding of intraspecific variation existing within the species, providing precautionary evidence of incipient speciation, and a framework of describing phenotypic diversity that is correlated with ecological conditions.  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 96 , 266–281.  相似文献   
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