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A B Edmundson K R Ely D A Sly F A Westholm D A Powers I E Liener 《Biochemistry》1971,10(19):3554-3559
44.
Eleanor A. Gidman M. Laurence M. Jones James A. Bussell Shelagh K. Malham Brian Reynolds Ray Seed David R. Causton Helen E. Johnson Dylan Gwynn-Jones 《Metabolomics : Official journal of the Metabolomic Society》2007,3(4):465-473
Developing effective, rapid and inexpensive methods for monitoring and conserving aquatic resources is an important issue
for environmental managers. This study focuses on Mytilus edulis, a keystone species of many coastal marine communities, which is frequently used as a biomonitor for a range of pollutants.
Recent advances in post-genomic technologies have provided new methods of biochemical screening, and Fourier transform-infrared
spectroscopy (FT-IR) is one such method that could enable bioindicator species to be used for environmental assessment. This
paper develops a methodology to apply the FT-IR approach to marine intertidal M. edulis and addresses three methodological issues: First, the optimum physical location for biofluid sampling is examined (i.e. laboratory
versus field). Secondly, the effects of transportation of frozen biofluid sampling from either the field-site or laboratory
to the analytical facility are considered. Finally, the effect of repeated FT-IR measurements on collected M. edulis haemolymph samples is examined. From these results we suggest sampling haemolymph from M. edulis at the top of the shore prior to immediate snap-freezing in liquid nitrogen. Sample transportation can occur on ice for up
to eight hours before storage at −80 °C. FT-IR measurements should occur within three months of collection and samples should
not be used or thawed more than twice. We show how this method can be used to differentiate successfully between four different
estuarine environments. Ultimately, through addressing these methodological questions, we provide a protocol to allow efficient
sampling and FT-IR measurement of M. edulis as collected from the intertidal areas of rocky and muddy shores. We conclude that due to current monitoring needs presented
by the European Water Framework Directive such an approach could prove to be an invaluable future tool for assessing coastal
water quality. 相似文献
45.
I Williamson R Eskeland LA Lettice AE Hill S Boyle GR Grimes RE Hill WA Bickmore 《Development (Cambridge, England)》2012,139(17):3157-3167
A late phase of HoxD activation is crucial for the patterning and growth of distal structures across the anterior-posterior (A-P) limb axis of mammals. Polycomb complexes and chromatin compaction have been shown to regulate Hox loci along the main body axis in embryonic development, but the extent to which they have a role in limb-specific HoxD expression, an evolutionary adaptation defined by the activity of distal enhancer elements that drive expression of 5' Hoxd genes, has yet to be fully elucidated. We reveal two levels of chromatin topology that differentiate distal limb A-P HoxD activity. Using both immortalised cell lines derived from posterior and anterior regions of distal E10.5 mouse limb buds, and analysis in E10.5 dissected limb buds themselves, we show that there is a loss of polycomb-catalysed H3K27me3 histone modification and a chromatin decompaction over HoxD in the distal posterior limb compared with anterior. Moreover, we show that the global control region (GCR) long-range enhancer spatially colocalises with the 5' HoxD genomic region specifically in the distal posterior limb. This is consistent with the formation of a chromatin loop between 5' HoxD and the GCR regulatory module at the time and place of distal limb bud development when the GCR participates in initiating Hoxd gene quantitative collinearity and Hoxd13 expression. This is the first example of A-P differences in chromatin compaction and chromatin looping in the development of the mammalian secondary body axis (limb). 相似文献
46.
Endocycles, which are characterised by repeated rounds of DNA replication without intervening mitosis, are involved in developmental processes associated with an increase in metabolic cell activity and are part of terminal differentiation. Endocycles are currently viewed as a restriction of the canonical cell cycle. As such, mitotic cyclins have been omitted from the endocycle mechanism and their role in this process has not been specifically analysed. In order to study such a role, we focused on CycA, which has been described to function exclusively during mitosis in Drosophila. Using developing mechanosensory organs as model system and PCNA::GFP to follow endocycle dynamics, we show that (1) CycA proteins accumulate during the last period of endoreplication, (2) both CycA loss and gain of function induce changes in endoreplication dynamics and reduce the number of endocycles, and (3) heterochromatin localisation of ORC2, a member of the Pre-RC complex, depends on CycA. These results show for the first time that CycA is involved in endocycle dynamics in Drosophila. As such, CycA controls the final ploidy that cells reached during terminal differentiation. Furthermore, our data suggest that the control of endocycles by CycA involves the subnuclear relocalisation of pre-RC complex members. Our work therefore sheds new light on the mechanism underlying endocycles, implicating a process that involves remodelling of the entire cell cycle network rather than simply a restriction of the canonical cell cycle. 相似文献
47.
Ramsland PA Terzyan SS Cloud G Bourne CR Farrugia W Tribbick G Geysen HM Moomaw CR Slaughter CA Edmundson AB 《The Biochemical journal》2006,399(3):473-481
An increase in circulating levels of specific NEFAs (non-esterified fatty acids) has been implicated in the pathogenesis of insulin resistance and impaired glucose disposal in skeletal muscle. In particular, elevation of SFAs (saturated fatty acids), such as palmitate, has been correlated with reduced insulin sensitivity, whereas an increase in certain MUFAs and PUFAs (mono- and poly-unsaturated fatty acids respectively) has been suggested to improve glycaemic control, although the underlying mechanisms remain unclear. In the present study, we compare the effects of palmitoleate (a MUFA) and palmitate (a SFA) on insulin action and glucose utilization in rat L6 skeletal muscle cells. Basal glucose uptake was enhanced approx. 2-fold following treatment of cells with palmitoleate. The MUFA-induced increase in glucose transport led to an associated rise in glucose oxidation and glycogen synthesis, which could not be attributed to activation of signalling proteins normally modulated by stimuli such as insulin, nutrients or cell stress. Moreover, although the MUFA-induced increase in glucose uptake was slow in onset, it was not dependent upon protein synthesis, but did, nevertheless, involve an increase in the plasma membrane abundance of GLUT1 and GLUT4. In contrast, palmitate caused a substantial reduction in insulin signalling and insulin-stimulated glucose transport, but was unable to antagonize the increase in transport elicited by palmitoleate. Our findings indicate that SFAs and MUFAs exert distinct effects upon insulin signalling and glucose uptake in L6 muscle cells and suggest that a diet enriched with MUFAs may facilitate uptake and utilization of glucose in normal and insulin-resistant skeletal muscle. 相似文献
48.
Towards a definition of a crop wild relative 总被引:4,自引:0,他引:4
Nigel Maxted Brian V. Ford-Lloyd Stephen Jury Shelagh Kell Maria Scholten 《Biodiversity and Conservation》2006,15(8):2673-2685
Crop wild relatives are an important socio-economic resource that is currently being eroded or even extinguished through careless
human activities. If the Conference of the Parties (COP) to the CBD 2010 Biodiversity Target of achieving a significant reduction
in the current rate of loss is to be achieved, we must first define what crop wild relatives are and how their conservation
might be prioritised. A definition of a crop wild relative is proposed and illustrated in the light of previous Gene Pool
concept theory. Where crossing and genetic diversity information is unavailable, the Taxon Group concept is introduced to
assist recognition of the degree of crop wild relative relatedness by using the existing taxonomic hierarchy. 相似文献
49.
Adriane Martin Hilber Suzanna C. Francis Matthew Chersich Pippa Scott Shelagh Redmond Nicole Bender Paolo Miotti Marleen Temmerman Nicola Low 《PloS one》2010,5(2)
Background
Intravaginal practices are commonly used by women to manage their vaginal health and sexual life. These practices could, however, affect intravaginal mucosal integrity. The objectives of this study were to examine evidence for associations between: intravaginal practices and acquisition of HIV infection; intravaginal practices and vaginal infections; and vaginal infections and HIV acquisition.Methodology/Principal Findings
We conducted a systematic review of prospective longitudinal studies, searching 15 electronic databases of journals and abstracts from two international conferences to 31st January 2008. Relevant articles were selected and data extracted in duplicate. Results were examined visually in forest plots and combined using random effects meta-analysis where appropriate. Of 2120 unique references we included 22 publications from 15 different studies in sub-Saharan Africa and the USA. Seven publications from five studies examined a range of intravaginal practices and HIV infection. No specific vaginal practices showed a protective effect against HIV or vaginal infections. Insertion of products for sex was associated with HIV in unadjusted analyses; only one study gave an adjusted estimate, which showed no association (hazard ratio 1.09, 95% confidence interval, CI 0.71, 1.67). HIV incidence was higher in women reporting intravaginal cleansing but confidence intervals were wide and heterogeneity high (adjusted hazard ratio 1.88, 95%CI 0.53, 6.69, I2 83.2%). HIV incidence was higher in women with bacterial vaginosis (adjusted effect 1.57, 95%CI 1.26, 1.94, I2 19.0%) and Trichomonas vaginalis (adjusted effect 1.64, 95%CI 1.28, 2.09, I2 0.0%).Conclusions/Significance
A pathway linking intravaginal cleaning practices with vaginal infections that increase susceptibility to HIV infection is plausible but conclusive evidence is lacking. Intravaginal practices do not appear to protect women from vaginal infections or HIV and some might be harmful. 相似文献50.
From the southern right whale hunting decline to the humpback whaling expansion: a review of whale catch records in the tropical western South Atlantic Ocean 下载免费PDF全文
Igor Oliveira Braga de Morais Daniel Danilewicz Alexandre Novaes Zerbini William Edmundson Ian B. Hart Guilherme Augusto Bortolotto 《Mammal Review》2017,47(1):11-23