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63.
SUSAN TAX FREEMAN 《American anthropologist》1968,70(1):34-49
The functional context of local religious practices within the structure of formal Catholicism in Spain has received little attention. Close examination of the ceremonial life of a Castilian village, and of the attitudes accompanying ceremonial and nonceremonial events, points to the existence of a complex of political and economic activities that are the chief objects of ritual sanctification and the arena in which religious sanctions function to maintain social control in the community. A survey of the ethnographic literature indicates that religious ceremonial may function in similar contexts in extended areas of the Iberian peninsula. The Castilian case and the available comparative data point to the crucial role of local religious traditions in strengthening territorial ties and in helping to define and integrate some of the fundamental units of the social structure. 相似文献
64.
Vestiges of an ancestral host plant: preference and performance in the butterfly Polygonia faunus and its sister species P. c‐album 下载免费PDF全文
SÖREN NYLIN LINA SÖDERLIND GABRIELLA GAMBERALE‐STILLE HÉLÈNE AUDUSSEAU MARIA DE LA PAZ CELORIO‐MANCERA NIKLAS JANZ FELIX A. H. SPERLING 《Ecological Entomology》2015,40(3):307-315
1. In the study of the evolution of insect–host plant interactions, important information is provided by host ranking correspondences among female preference, offspring preference, and offspring performance. Here, we contrast such patterns in two polyphagous sister species in the butterfly family Nymphalidae, the Nearctic Polygonia faunus, and the Palearctic P. c‐album. 2. These two species have similar host ranges, but according to the literature P. faunus does not use the ancestral host plant clade – the ‘urticalean rosids’. Comparisons of the species can thus test the effects of a change in insect–plant associations over a long time scale. Cage experiments confirmed that P. faunus females avoid laying eggs on Urtica dioica (the preferred host of P. c‐album), instead preferring Salix, Betula, and Ribes. 3. However, newly hatched larvae of both species readily accept and grow well on U. dioica, supporting the general theory that evolutionary changes in host range are initiated through shifts in female host preferences, whereas larvae are more conservative and also can retain the capacity to perform well on ancestral hosts over long time spans. 4. Similar rankings of host plants among female preference, offspring preference, and offspring performance were observed in P. c‐album but not in P. faunus. This is probably a result of vestiges of larval adaptations to the lost ancestral host taxon in the latter species. 5. Female and larval preferences seem to be largely free to evolve independently, and consequently larval preferences warrant more attention. 相似文献
65.
Changing demography and population decline in the Common Starling Sturnus vulgaris: a multisite approach to Integrated Population Monitoring 总被引:2,自引:1,他引:1
STEPHEN N. FREEMAN ROBERT A. ROBINSON JACQUIE A. CLARK BRIDGET M. GRIFFIN & SUE Y. ADAMS 《Ibis》2007,149(3):587-596
Understanding demography is critical for understanding the causes underlying population declines, and for initiating and monitoring policies to reverse them. A method of fitting demographic models directly to avian count data recorded at a sample of census sites is described. The model is applied to national and regional counts of Common Starling Sturnus vulgaris in Britain for the period 1965–2000. Starlings have declined markedly during this time and are now on the list of birds of highest conservation concern. Although there have been small changes in various aspects of breeding success over this time, the analysis shows that these are unlikely to have made much impact on the long-term status of the species. By incorporating estimates of survival, based upon recoveries of ringed birds, the model suggests that the pronounced national decline in Starling numbers since a period of stability in the 1970s is most likely to be due to changes in the survival of first-year birds. This narrows the candidate range of environmental factors which might influence the decline and implicates changes in resource availability. 相似文献
66.
Variability within a pea core collection of LEAM and HSP22, two mitochondrial seed proteins involved in stress tolerance 下载免费PDF全文
MARIE‐HÉLÈNE AVELANGE‐MACHEREL NICOLE PAYET DAVID LALANNE MARTINE NEVEU DIMITRI TOLLETER JUDITH BURSTIN DAVID MACHEREL 《Plant, cell & environment》2015,38(7):1299-1311
LEAM, a late embryogenesis abundant protein, and HSP22, a small heat shock protein, were shown to accumulate in the mitochondria during pea (Pisum sativum L.) seed development, where they are expected to contribute to desiccation tolerance. Here, their expression was examined in seeds of 89 pea genotypes by Western blot analysis. All genotypes expressed LEAM and HSP22 in similar amounts. In contrast with HSP22, LEAM displayed different isoforms according to apparent molecular mass. Each of the 89 genotypes harboured a single LEAM isoform. Genomic and RT‐PCR analysis revealed four LEAM genes differing by a small variable indel in the coding region. These variations were consistent with the apparent molecular mass of each isoform. Indels, which occurred in repeated domains, did not alter the main properties of LEAM. Structural modelling indicated that the class A α‐helix structure, which allows interactions with the mitochondrial inner membrane in the dry state, was preserved in all isoforms, suggesting functionality is maintained. The overall results point out the essential character of LEAM and HSP22 in pea seeds. LEAM variability is discussed in terms of pea breeding history as well as LEA gene evolution mechanisms. 相似文献
67.
INTRODUCTION It has been over twenty years since the onset of the AIDS epidemic, and in spite of the tremendous progress made towards the understanding of the disease, the virus that causes the disease and the development of highly ef- fective anti-retrov… 相似文献
68.
LM Harris L Blank RP Desai NE Welker ET Papoutsakis 《Journal of industrial microbiology & biotechnology》2001,27(5):322-328
The effect of solR inactivation on the metabolism of Clostridium acetobutylicum was examined using fermentation characterization and metabolic flux analysis. The solR-inactivated strain (SolRH) of this study had a higher rate of glucose utilization and produced higher solvent concentrations
(by 25%, 14%, and 81%, respectively, for butanol, acetone, and ethanol) compared to the wild type. Strain SolRH(pTAAD), carrying
a plasmid-encoded copy of the bifunctional alcohol/aldehyde dehydrogenase gene (aad) used in butanol production, produced even higher concentrations of solvents (by 21%, 45%, and 62%, respectively, for butanol,
acetone, and ethanol) than strain SolRH. Clarithromycin used for strain SolRH maintenance during SolRH(pTAAD) fermentations
did not alter product formation; however, tetracycline used for pTAAD maintenance resulted in 90% lower solvent production.
Journal of Industrial Microbiology & Biotechnology (2001) 27, 322–328.
Received 12 September 2000/ Accepted in revised form 21 July 2001 相似文献
69.
Estimation in parameter-redundant models 总被引:3,自引:0,他引:3
70.
Elevated CO2 decreases seed germination in Arabidopsis thaliana 总被引:2,自引:0,他引:2
CHRISTOPHE ANDALO BERNARD GODELLE † MADELEINE LEFRANC MARIANNE MOUSSEAU IRÉNE TILL-BOTTRAUD 《Global Change Biology》1996,2(2):129-135
The impact of elevated [CO2] on seed germination was studied in different genotypes of Arabidopsis thaliana from natural populations. Two generations of seeds were studied: the maternal generation was produced in the greenhouse (present-day conditions), the offspring generation was produced in two chambers where the CO2 concentration was either the present atmospheric concentration (about 350 ppm) or elevated (700 ppm). The seeds were tested for proportion of germinated seeds and mean germination time in both chambers to study the impact of elevated [CO2] during seed production and germination. Elevated [CO2] during maturation of seeds on the mother-plants decreased the proportion of germinated seeds, while elevated [CO2] during germination had no effect on the proportion of germinated seeds. However, when seeds were both produced and germinated under elevated [CO2] (situation expected by the end of next century), germination was slow and low. Moreover, the effect of the [CO2] treatment differs among genotypes of Arabidopsis: there is a strong treatment × genotype interaction. This means that there is ample genetic variance for a selective response modiying the effects of high levels of [CO2] in natural populations of Arabidopsis thaliana. The outcome at the community level will depend on what seeds are available, when they germinate and the resulting competition following germination. 相似文献