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41.
42.
Haluk Topcuoglu Salim Hariri Dongmin Kim Yoonhee Kim Xue Bing Baoqing Ye Ilkyeun Ra Jon Valente 《Cluster computing》1998,1(1):81-93
Current advances in high-speed networks such as ATM and fiber-optics, and software technologies such as the JAVA programming
language and WWW tools, have made network-based computing a cost-effective, high-performance distributed computing environment.
Metacomputing, a special subset of network-based computing, is a well-integrated execution environment derived by combining
diverse and distributed resources such as MPPs, workstations, mass storage, and databases that show a heterogeneous nature
in terms of hardware, software, and organization. In this paper we present the Virtual Distributed Computing Environment (VDCE),
a metacomputing environment currently being developed at Syracuse University. VDCE provides an efficient web-based approach
for developing, evaluating, and visualizing large-scale distributed applications that are based on predefined task libraries
on diverse platforms. The VDCE task libraries relieve end-users of tedious task implementations and also support reusability.
The VDCE software architecture is described in terms of three modules: (a) the Application Editor, a user-friendly application
development environment that generates the Application Flow Graph (AFG) of an application; (b) the Application Scheduler,
which provides an efficient task-to-resource mapping of AFG; and (c) the VDCE Runtime System, which is responsible for running
and managing application execution and for monitoring the VDCE resources. We present experimental results of an application
execution on the VDCE prototype for evaluating the performance of different machine and network configurations. We also show
how the VDCE can be used as a problem-solving environment on which large-scale, network-centric applications can be developed
by a novice programmer rather than by an expert in low-level details of parallel programming languages.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
43.
Gaurav Patki Ankita Salvi Hesong Liu Fatin Atrooz Isam Alkadhi Matthew Kelly Samina Salim 《PloS one》2015,10(3)
We have published that pharmacological induction of oxidative stress (OS) causes anxiety-like behavior in rats. Using animal models, we also have established that psychological stress induces OS and leads to anxiety-like behaviors. All evidence points towards the causal role of OS in anxiety-like behaviors. To fully ascertain the role of OS in anxiety-like behaviors, it is reasonable to test whether the pro-anxiety effects of anxiogenic drugs caffeine or N-methyl-beta-carboline-3-carboxamide (FG-7142) can be mitigated using agents that minimize OS. In this study, osmotic pumps were either filled with antioxidant tempol or saline. The pumps were attached to the catheter leading to the brain cannula and inserted into the subcutaneous pocket in the back pocket of the rat. Continuous i.c.v. infusion of saline or tempol in the lateral ventricle of the brain (4.3mmol/day) was maintained for 1 week. Rats were intraperitoneally injected either with saline or an anxiogenic drug one at a time. Two hours later all groups were subjected to behavioral assessments. Anxiety-like behavior tests (open-field, light-dark and elevated plus maze) suggested that tempol prevented anxiogenic drug-induced anxiety-like behavior in rats. Furthermore, anxiogenic drug-induced increase in stress examined via plasma corticosterone and increased oxidative stress levels assessed via plasma 8-isoprostane were prevented with tempol treatment. Protein carbonylation assay also suggested preventive effect of tempol in the prefrontal cortex brain region of rats. Antioxidant protein expression and pro-inflammatory cytokine levels indicate compromised antioxidant defense as well as an imbalance of inflammatory response. 相似文献
44.
Maureen Njue Sassy Molyneux Francis Kombe Salim Mwalukore Dorcas Kamuya Vicki Marsh 《PloS one》2015,10(5)
BackgroundProviding benefits and payments to participants in health research, either in cash or in kind, is a common but ethically controversial practice. While much literature has concentrated on appropriate levels of benefits or payments, this paper focuses on less well explored ethical issues around the nature of study benefits, drawing on views of community members living close to an international health research centre in Kenya.MethodsThe consultation, including 90 residents purposively chosen to reflect diversity, used a two-stage deliberative process. Five half-day workshops were each followed by between two and four small group discussions, within a two week period (total 16 groups). During workshops and small groups, facilitators used participatory methods to share information, and promote reflection and debate on ethical issues around types of benefits, including cash, goods, medical and community benefits. Data from workshop and field notes, and voice recordings of small group discussions, were managed using Nvivo 10 and analysed using a Framework Analysis approach.
Findings and Conclusions
The methods generated in-depth discussion with high levels of engagement. Particularly for the most-poor, under-compensation of time in research carries risks of serious harm. Cash payments may best support compensation of costs experienced; while highly valued, goods and medical benefits may be more appropriate as an ‘appreciation’ or incentive for participation. Community benefits were seen as important in supporting but not replacing individual-level benefits, and in building trust in researcher-community relations. Cash payments were seen to have higher risks of undue inducement, commercialising relationships and generating family conflicts than other benefits, particularly where payments are high. Researchers should consider and account for burdens families may experience when children are involved in research. Careful context-specific research planning and skilled and consistent communication about study benefits and payments are important, including in mitigating potential negative effects. 相似文献45.
46.
47.
Xunbao Duan Steve G. Kelsen Allen B. Clarkson Jr Rong Ji Salim Merali 《Proteomics》2010,10(11):2165-2174
To better understand lung oxidant stress responses, we examined A549 lung cells exposed to H2O2 using “stable isotope labeling by amino acids.” We identified 466 cytosolic and 387 nuclear proteins; H2O2 exposure produced ≥twofold differences in 31, all were downregulations. None were previously reported as oxidant stress response proteins, although they share common functions. One of the responders, treacle, was linked to p53, an important oxidative stress response. The Treacher Collins–Franceschetti syndrome can result from treacle mutation and insufficiency was suggested to cause increased p53 leading to the syndrome. However, results here indicate p53 and treacle responses to H2O2 are independent: treacle remains suppressed after p53 recovery; the threshold for treacle reduction is well above that for p53 induction; and treacle suppression by short interfering RNA does not modify the p53 response. Evidence of treacle antioxidant activity include reduction being driven by proteasome degradation independently of mRNA, typical for oxidant‐absorbing proteins, and increased sensitivity to H2O2 consequent to short interfering RNA suppression. Data here show a link between oxidative stress and treacle reduction, demonstrate that treacle does not control p53, provide evidence of a treacle oxidant defense role, support the hypothesis that oxidant stress plays a role in the Treacher Collins–Franceschetti syndrome, and raise the possibility that treacle plays an anti‐oxidant role in lungs. 相似文献
48.
Carotenoids are converted by carotenoid cleavage dioxygenases that catalyze oxidative cleavage reactions leading to apocarotenoids.
However, apocarotenoids can also be further truncated by some members of this enzyme family. The plant carotenoid cleavage
dioxygenase 1 (CCD1) subfamily is known to degrade both carotenoids and apocarotenoids in vitro, leading to different volatile
compounds. In this study, we investigated the impact of the rice CCD1 (OsCCD1) on the pigmentation of Golden Rice 2 (GR2),
a genetically modified rice variety accumulating carotenoids in the endosperm. For this purpose, the corresponding cDNA was
introduced into the rice genome under the control of an endosperm-specific promoter in sense and anti-sense orientations.
Despite high expression levels of OsCCD1 in sense plants, pigment analysis revealed carotenoid levels and patterns comparable
to those of GR2, pleading against carotenoids as substrates in rice endosperm. In support, similar carotenoid contents were
determined in anti-sense plants. To check whether OsCCD1 overexpressed in GR2 endosperm is active, in vitro assays were performed
with apocarotenoid substrates. HPLC analysis confirmed the cleavage activity of introduced OsCCD1. Our data indicate that
apocarotenoids rather than carotenoids are the substrates of OsCCD1 in planta. 相似文献
49.
Raed Salim Gali Garmi Zohar Nachum Eliezer Shalev 《Reproductive biology and endocrinology : RB&E》2010,8(1):81
Background
Variable decelerations are the most frequent fetal heart rate changes that are related to labor. The objective of the study was to estimate the impact of non-significant variable decelerations (NSV) appearing during the latent phase of labor on delivery mode and neonatal outcome. 相似文献50.