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101.
102.
Paul A. Rees 《Journal of applied animal welfare science : JAAWS》2013,16(1):44-60
This study examined the distribution of 495 Asian elephants (Elephas maximus) and 336 African elephants (Loxodonta africana) in 194 zoos, most of which were located in Europe (49.1%) and North America (32.6%). Cows outnumbered bulls 4 to 1 (Loxodonta) and 3 to 1 (Elephas). Groups contained 7 or fewer: mean, 4.28 (σ = 5.73). One fifth of elephants lived alone or with one conspecific. Forty-six elephants (5.5%) had no conspecific. Many zoos ignore minimum group sizes of regional zoo association guidelines. The American Zoo and Aquarium Association recommends that breeding facilities keep herds of 6 to 12 elephants. The British and Irish Association of Zoos and Aquariums recommends keeping together at least 4 cows over 2 years old. Over 69% Asian and 80% African cow groups—including those under 2 years—consisted of fewer than 4 individuals. Recently, Europe and North America have made progress with some zoos no longer keeping elephants and with others investing in improved facilities and forming larger herds. The welfare of individual elephants should outweigh all other considerations; zoos should urgently seek to integrate small groups into larger herds. 相似文献
103.
Lena M. Jonsson Daryl D. Rees Thomas Edlund Stefan L. Marklund 《Free radical research》2013,47(7):755-758
Nitric oxide is a major vasorelaxant and regulator of the blood pressure. The blood vessels contain several active sources of the superoxide radical, which reacts avidly with nitric oxide to form noxious peroxynitrite. There are large amounts of extracellular-superoxide dismutase (EC-SOD) in the vascular wall. To evaluate the importance of EC-SOD for the physiology of nitric oxide, here we studied the blood pressure in mice lacking the enzyme. In chronically instrumented non-anaesthetized mice there was no difference in mean arterial blood pressure between wild-type controls and EC-SOD mutants. Extensive inhibition of nitric oxide synthases with N -monomethyl- l -arginine however resulted in a larger increase in blood pressure, and infusion of the nitric oxide donor nitrosoglutathione caused less reduction in blood pressure in the EC-SOD null mice. We interpret the alterations to be caused by a moderately increased consumption of nitric oxide by the superoxide radical in the EC-SOD null mice. One role of EC-SOD may be to preserve nitric oxide, a function that should be particularly important in vascular pathologies, in which large increases in superoxide formation have been documented. 相似文献
104.
Susan Rees Derrick Silove Teresa Verdial Natalino Tam Elisa Savio Zulmira Fonseca Rosamund Thorpe Belinda Liddell Anthony Zwi Kuowei Tay Robert Brooks Zachary Steel 《PloS one》2013,8(8)
Introduction
Women in conflict-affected countries are at risk of mental disorders such as posttraumatic stress disorder and depression. No studies have investigated the association between experiences of abuse and injustice and explosive anger amongst women in these settings, and the impact of anger on women''s health, family relationships and ability to participate in development.Methods
A mixed methods study including an epidemiological survey (n = 1513, 92.6% response) and qualitative interviews (n = 77) was conducted in Timor-Leste. The indices measured included Intermittent Explosive Disorder, posttraumatic stress disorder; severe distress; days out of role (the number of days that the person was unable to undertake normal activities); gender-specific trauma; conflict/violence; poverty; and preoccupations with injustice.Results
Women with Intermittent Explosive Disorder (n = 184, 12.2%) were more disabled than those without the disorder (for >5 days out of role, 40.8% versus 31.5%, X2 (2) = 12.93 p = 0.0016). Multivariable associations with Intermittent Explosive Disorder, controlling for the presence of PTSD, psychological distress and other predictors in the model, included the sense of being sick (OR 1.73; 95% CI 1.08–2.77); victimization as a result of helping the resistance movement (OR 2.33, 95% CI 1.48–3.68); war-related trauma specific to being a woman (OR 1.95, 95%, CI 1.09–3.50); ongoing family violence and community conflict (OR 1.88, 95% CI 1.27–2.77); extreme poverty (OR 1.23, 95%, CI 1.08–1.39); and distressing preoccupations with injustice (relating to 2/3 historical periods, OR 2.10, 95% CI 1.35–3.28). In the qualitative study, women elaborated on the determinants of anger and its impact on their health, family and community functioning, child-rearing, and capacity to engage in development. Women reflected on the strategies that might help them overcome their anger.Conclusions
Intermittent Explosive Disorder is prevalent and disabling amongst women in conflict-affected Timor-Leste, impacting on their health, child-rearing and ability to participate fully in socio-economic development. 相似文献105.
Fern Terris-Prestholt Kara Hanson Catherine MacPhail Peter Vickerman Helen Rees Charlotte Watts 《PloS one》2013,8(12)
Background
For the first time in the history of HIV, new bio-medical interventions have been shown to be effective in preventing HIV transmission. For these new HIV prevention technologies (NPTs) to have an impact on the epidemic, they must be widely used. This study uses a discrete choice experiment (DCE) to: understand the relative strength of women’s preferences for product characteristics, understand the implications for substitution away from male condoms, and inform realistic modelling of their potential impact and cost-effectiveness.Methods
A DCE was conducted among 1017 women in urban South Africa. Women were presented with choices between potential women’s NPTs (microbicides, diaphragm, female condom) and ‘what I did last time’ (use or not use a condom) with different HIV and pregnancy prevention effectiveness’ and prices. Choice probabilities are estimated using the nested logit model and used to predict uptake.Results
In this high HIV prevalence setting, HIV prevention effectiveness is the main driver of uptake followed by pregnancy prevention effectiveness. For example a microbicide with poor effectiveness would have niche appeal at just 11% predicted uptake, while a highly effective microbicide (95% effective against HIV and pregnancy) would have far wider appeal (56% predicted uptake). Though women who reported not using condoms were more likely to choose the NPTs, at current very high rates of male condom use in South Africa (60%), about half of microbicide uptake is projected to be among those currently not using condoms.Conclusions
Women are very interested in NPTs, especially if highly effective in preventing HIV and pregnancy. Women in greatest need were also most likely to switch to the new products. Where products are not yet available for distribution, proxy data, such as that generated by DCEs, can bring realism to overly optimistic uptake scenarios found in many current impact models. 相似文献106.
107.
Rees Burt Bridget M. Graves Ming Gao Chaunfu Li David L. Williams Santiago P. Fregoso Donald B. Hoover Ying Li Gary L. Wright Robert Wondergem 《Cell calcium》2013
It is well established that intracellular calcium ([Ca2+]i) controls the inotropic state of the myocardium, and evidence mounts that a “Ca2+ clock” controls the chronotropic state of the heart. Recent findings describe a calcium-activated nonselective cation channel (NSCCa) in various cardiac preparations sharing hallmark characteristics of the transient receptor potential melastatin 4 (TRPM4). TRPM4 is functionally expressed throughout the heart and has been implicated as a NSCCa that mediates membrane depolarization. However, the functional significance of TRPM4 in regards to Ca2+ signaling and its effects on cellular excitability and pacemaker function remains inconclusive. Here, we show by Fura2 Ca-imaging that pharmacological inhibition of TRPM4 in HL-1 mouse cardiac myocytes by 9-phenanthrol (10 μM) and flufenamic acid (10 and 100 μM) decreases Ca2+ oscillations followed by an overall increase in [Ca2+]i. The latter occurs also in HL-1 cells in Ca2+-free solution and after depletion of sarcoplasmic reticulum Ca2+ with thapsigargin (10 μM). These pharmacologic agents also depolarize HL-1 cell mitochondrial membrane potential. Furthermore, by on-cell voltage clamp we show that 9-phenanthrol reversibly inhibits membrane current; by fluorescence immunohistochemistry we demonstrate that HL-1 cells display punctate surface labeling with TRPM4 antibody; and by immunoblotting using this antibody we show these cells express a 130–150 kDa protein, as expected for TRPM4. We conclude that 9-phenanthrol inhibits TRPM4 ion channels in HL-1 cells, which in turn decreases Ca2+ oscillations followed by a compensatory increase in [Ca2+]i from an intracellular store other than the sarcoplasmic reticulum. We speculate that the most likely source is the mitochondrion. 相似文献
108.
Darren S. Baldwin Matthew J. Colloff Gavin N. Rees Anthony A. Chariton Garth O. Watson Leon N. Court Diana M. Hartley Matthew j. Morgan Andrew J. King Jessica S. Wilson Michael Hodda Christopher M. Hardy 《Molecular ecology》2013,22(6):1746-1758
Floodplain ecosystems are characterized by alternating wet and dry phases and periodic inundation defines their ecological character. Climate change, river regulation and the construction of levees have substantially altered natural flooding and drying regimes worldwide with uncertain effects on key biotic groups. In southern Australia, we hypothesized that soil eukaryotic communities in climate change affected areas of a semi‐arid floodplain would transition towards comprising mainly dry‐soil specialist species with increasing drought severity. Here, we used 18S rRNA amplicon pyrosequencing to measure the eukaryote community composition in soils that had been depleted of water to varying degrees to confirm that reproducible transitional changes occur in eukaryotic biodiversity on this floodplain. Interflood community structures (3 years post‐flood) were dominated by persistent rather than either aquatic or dry‐specialist organisms. Only 2% of taxa were unique to dry locations by 8 years post‐flood, and 10% were restricted to wet locations (inundated a year to 2 weeks post‐flood). Almost half (48%) of the total soil biota were detected in both these environments. The discovery of a large suite of organisms able to survive nearly a decade of drought, and up to a year submerged supports the concept of inherent resilience of Australian semi‐arid floodplain soil communities under increasing pressure from climatic induced changes in water availability. 相似文献
109.
Jens T. Kaiser Douglas C. Rees 《Protein science : a publication of the Protein Society》2013,22(4):502-509
The mechanosensitive channel of small conductance (MscS) contributes to the survival of bacteria during osmotic downshock by transiently opening large diameter pores for the efflux of cellular contents before the membrane ruptures. Two crystal structures of the Escherichia coli MscS are currently available, the wild type protein in a nonconducting state at 3.7 Å resolution (Bass et al., Science 2002; 298:1582–1587) and the Ala106Val variant in an open state at 3.45 Å resolution (Wang et al., Science 2008; 321:1179–1183). Both structures used protein solubilized in the detergent fos‐choline‐14. We report here crystal structures of MscS from E. coli and Helicobacter pylori solubilized in the detergent β‐dodecylmaltoside at resolutions of 4.4 and 4.2 Å, respectively. While the cytoplasmic domains are unchanged in these structures, distinct conformations of the transmembrane domains are observed. Intriguingly, β‐dodecylmaltoside solubilized wild type E. coli MscS adopts the open state structure of A106V E. coli MscS, while H. pylori MscS resembles the nonconducting state structure observed for fos‐choline‐14 solubilized E. coli MscS. These results highlight the sensitivity of membrane protein conformational equilibria to variations in detergent, crystallization conditions, and protein sequence. 相似文献
110.
The invasive freshwater mollusc Dreissena bugensis (quagga mussel) sticks to underwater surfaces via a proteinacious ‘anchor’ (byssus), consisting of a series of threads linked to adhesive plaques. This adhesion results in the biofouling of crucial underwater industry infrastructure, yet little is known about the proteins responsible for the adhesion. Here the identification of byssal proteins extracted from freshly secreted byssal material is described. Several new byssal proteins were observed by gel electrophoresis. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was used to characterize proteins in different regions of the byssus, particularly those localized to the adhesive interface. Byssal plaques and threads contain in common a range of low molecular weight proteins, while several proteins with higher mass were observed only in the plaque. At the adhesive interface, a plaque-specific ~8.1 kDa protein had a relative increase in signal intensity compared to the bulk of the plaque, suggesting it may play a direct role in adhesion. 相似文献