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441.
Pizzirani Stefania McLaren Sarah J. Forster Margaret E. Pohatu Pia Porou Tina Tangi Whaiora Warmenhoven Tui Aroha 《The International Journal of Life Cycle Assessment》2018,23(3):663-682
The International Journal of Life Cycle Assessment - Cultural indicators, although present in S-LCA subcategories, are fairly limited and are not compulsory; performing an S-LCA does not guarantee... 相似文献
442.
David G. McLaren Seongah Han Beth Ann Murphy Larissa Wilsie Steven J. Stout Haihong Zhou Thomas P. Roddy Judith N. Gorski Daniel E. Metzger Myung K. Shin Dermot F. Reilly Heather H. Zhou Marija Tadin-Strapps Steven R. Bartz Anne-Marie Cumiskey Thomas H. Graham Dong-Ming Shen Karen O. Akinsanya Shirly Pinto 《Cell metabolism》2018,27(6):1236-1248.e6
443.
R M Matossian M L McLaren C C Draper C M Bradstreet M W Dighero G J Kane L M Mackinlay M D Rickard 《Journal of helminthology》1979,53(4):287-291
Sixty-one serum samples selected on the basis of reactivity in the complement fixation (CF) and latex agglutination (LA) test, were further examined for sensitivity and specificity by indirect haemagglutination (IHA), enzyme linked immunosorbent assay (ELISA) and defined antigen substrate spheres (DASS). Twenty sera from healthy Europeans and 48 samples from patients with either schistosomiasis or trichinosis were also tested. Comparable levels of sensitivity were found between the CF and LA positive sera and IHA, ELISA and DASS. Of the CF positive LA negative group of sera, many were positive by DASS but only a few reacted in IHA and ELISA. Some cross reactivity was also observed in the schistosomiasis sera tested by IHA and ELISA. 相似文献
444.
Roland R. Regoes Paul J. McLaren Manuel Battegay Enos Bernasconi Alexandra Calmy Huldrych F. Günthard Matthias Hoffmann Andri Rauch Amalio Telenti Jacques Fellay the Swiss HIV Cohort Study 《PLoS biology》2014,12(9)
In ecology, “disease tolerance” is defined as an evolutionary strategy of hosts against pathogens, characterized by reduced or absent pathogenesis despite high pathogen load. To our knowledge, tolerance has to date not been quantified and disentangled from host resistance to disease in any clinically relevant human infection. Using data from the Swiss HIV Cohort Study, we investigated if there is variation in tolerance to HIV in humans and if this variation is associated with polymorphisms in the human genome. In particular, we tested for associations between tolerance and alleles of the Human Leukocyte Antigen (HLA) genes, the CC chemokine receptor 5 (CCR5), the age at which individuals were infected, and their sex. We found that HLA-B alleles associated with better HIV control do not confer tolerance. The slower disease progression associated with these alleles can be fully attributed to the extent of viral load reduction in carriers. However, we observed that tolerance significantly varies across HLA-B genotypes with a relative standard deviation of 34%. Furthermore, we found that HLA-B homozygotes are less tolerant than heterozygotes. Lastly, tolerance was observed to decrease with age, resulting in a 1.7-fold difference in disease progression between 20 and 60-y-old individuals with the same viral load. Thus, disease tolerance is a feature of infection with HIV, and the identification of the mechanisms involved may pave the way to a better understanding of pathogenesis. 相似文献
445.
446.
The uptake of C14-labeled proteins (lysozyme, hemoglobin, lactoglobulin, and ovalbumin) from solution by tomato plants with sterile roots was studied. It was found that C14-compounds (proteins and/or protein-degradation products) were translocated to the foliage if the roots had undergone minor mechanical injury or if the plants were subjected to temporary wilting, i.e., physiological damage. C14-lysozyme was not transported to foliar tissue in healthy plants; C14-hemoglobin showed radioactivity in leaves of both healthy and injured plants, but there was evidence of a breakdown of the molecule; C14-ovalbumin gave a faint labeling of foliar tissues of some plants in which wilting or mechanical damage was below the threshold of detection. It is concluded, however, that translocation of proteins from roots in nutrient solution to tomato leaves does not occur in significant amounts in healthy plants in spite of the large uptake of proteins by root cortex, as found in earlier studies. 相似文献
447.
448.
Towards a reporter system to identify regulators of cross-talk between salicylate and jasmonate signaling pathways in Arabidopsis 总被引:1,自引:0,他引:1
Annemart Koornneef Adriaan Verhage Antonio Leon-Reyes Reinier Snetselaar LC Van Loon Corné MJ Pieterse 《Plant signaling & behavior》2008,3(8):543-546
The plant signaling hormones salicylic acid (SA) and jasmonic acid (JA) are regulators of inducible defenses that are activated upon pathogen or insect attack. Cross-talk between SA- and JA-dependent signaling pathways allows a plant to finely tune its response to the attacker encountered. In Arabidopsis, pharmacological experiments revealed that SA exerts a strong antagonistic effect on JA-responsive genes, such as PDF1.2, indicating that the SA pathway can be prioritized over the JA pathway. SA-mediated suppression of the JA-responsive PDF1.2 promoter was exploited for setting up a genetic screen aiming at the isolation of signal transduction mutants that are impaired in this cross-talk mechanism. The PDF1.2 promoter was fused to the herbicide resistance gene BAR to allow for life/death screening of a population of mutagenized transgenic plants. Non-mutant plants should survive herbicide treatment when methyl jasmonate (MeJA) is applied, but suppression of the JA response by SA should be lethal in combination with the herbicide. Conversely, crucial SA/JA cross-talk mutants should survive the combination treatment. SA effectively suppressed the expression of the PDF1.2::BAR transgene. However, suppression of the BAR gene did not result in suppression of herbicide resistance. Hence, a screening method based on quantitative differences in the expression of a reporter gene may be better suited to identify SA/JA cross-talk mutants. Here, we demonstrate that the PDF1.2::GUS reporter will be excellently suited in this respect.Key words: plant defense, salicylic acid, jasmonic acid, cross-talk, mutant screen, Arabidopsis 相似文献
449.
G. Durcova-Hills · J.F.-X. Ainscough · A. McLaren 《Differentiation; research in biological diversity》2001,68(4-5):220-226
Pluripotent stem cells termed embryonic germ cells (EGCs) have earlier been derived from pre- and post-migrating mouse primordial germ cells (PGCs). We have recently obtained four EGC lines from migrating PGCs of 9.5 days post coitum (dpc) embryos. All lines were male with normal karyotype and showed properties that are similar to previously established EGC lines, including colony morphology, expression of alkaline phosphatase (AP), and expression of SSEA-1 antigen. The developmental potency of two of these lines was tested in vivo. They contributed to a range of tissues in fetal chimeras including heart, lung, kidney, intestine, muscle, brain and skin. We also examined the methylation status of the imprinted genes: Igf2r, p57Kip2, Lit1, H19 and Igf2. Igf2r, p57Kip2 and Lit1 were unmethylated in all analysed EGC lines, whereas H19 and Igf2 showed significant hypo-methylation in the 9.5 dpc EGC-1 line when compared to previously derived 11.5 dpc male EGC lines. This suggests that imprint erasure in the male germ line occurs prior to 9.5 dpc for all imprinted genes examined. 相似文献
450.
Chanjief Chandrakumar Sarah J. McLaren Nihal P. Jayamaha Thiagarajah Ramilan 《Journal of Industrial Ecology》2019,23(4):906-917
Given the increasing environmental impacts associated with global agri‐food systems, operating and developing these systems within the so‐called absolute environmental boundaries has become crucial, and hence the absolute environmental sustainability concept is particularly relevant. This study introduces an approach called absolute sustainability‐based life cycle assessment (ASLCA) that informs the climate impacts of an agri‐food system (on any economic level) in absolute terms. First, a global carbon budget was calculated that is sufficient to limit global warming to below 2°C. Next, a share of the carbon budget available to the global agri‐food sector was estimated, and then it was shared between agri‐food systems on multiple economic levels using four alternative methods. Third, the climate impacts of those systems were calculated using life cycle assessment methodology and were benchmarked against those carbon budget shares. This approach was used to assess a number of New Zealand agri‐food systems (agri‐food sector, horticulture industries and products) to investigate how these systems operated relative to their carbon budget shares. The results showed that, in 2013, the New Zealand agri‐food systems were within their carbon budget shares for one of the four methods, and illustrated the scale of change required for agri‐food systems to perform within their carbon budget shares. This method can potentially be extended to consider other environmental impacts with global boundaries; however, further development of the ASLCA is necessary to account for other environmental impacts whose boundaries are only meaningful when defined at a regional or local level. 相似文献