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991.
Four rhesus macaque (Macaca mulatta) mothers each spontaneously adopted and reared an abandoned, unrelated neonate in addition to their own neonate. Data on relative time spent in maternal contact and who maintained proximity were collected for the biological and adopted “twins” and singleton control infants using focal animal sampling. Infant weight gain and the subsequent conception history for each mother were obtained for the following year. Biological infants spent more time in maternal contact than their adopted “twin” siblings. When in contact with their mothers, biological “twins” spent more time in the ventro-ventral position and more ventral time alone than adoptees. Mothers initiated more contacts with their biological infants than their adopted infants, suggesting these differences may be due to differential maternal behavior. “Twins” gained weight at a slower rate than singletons, and mothers rearing “twins” produced significantly fewer offspring the following season. Am. J. Primatol. 43:259–264, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
992.
The endothelium forms a continuous monolayer at the interface between blood and tissue and contributes significantly to the sensing and transducing of signals between blood and tissue. New blood vessel formation, or angiogenesis, is initiated by the activation of endothelial cells and is an important process required for various pathological and physiological situations. This study used cleavable isotope-coded affinity tag reagents combined with mass spectrometry to investigate the molecular basis of a recently discovered angiogenesis-promoting steroid, sokotrasterol sulfate. Changes in the relative abundances of over 1000 proteins within human endothelial cells treated with sokotrasterol sulfate and vehicle-treated cells were identified and quantitated using this technique. A method that examines the entire ensemble of quantitative measurements was developed to identify proteins that showed a statistically significant change in relative abundance resulting from treatment with sokotrasterol sulfate. A total of 93 proteins was significantly up-regulated, and 37 were down-regulated in response to sokotrasterol sulfate stimulation of endothelial cells. Among the up-regulated proteins, several were identified that are novel to endothelial cells and are likely involved in cell communication and morphogenesis. These findings are consistent with a role for sokotrasterol sulfate in endothelial sprouting.  相似文献   
993.
ObjectivesTo assess the non-specific effect of Bacillus Calmette-Guérin (BCG) vaccination at birth on psychomotor development.DesignThis is a pre-specified secondary outcome from a randomised, clinical trial.SettingMaternity units and paediatric wards at three university hospitals in Denmark.ParticipantsChildren born at gestational age (GA) 32 weeks and above. All women planning to give birth at the three sites were invited during the recruitment period. Out of 4262 randomised children, 144 were premature (GA < 37 weeks). There were 2129 children (71 premature) randomised to BCG and 2133 randomised (73 premature) to the control group.InterventionsBCG vaccination 0.05 ml was given intradermally in the upper left arm at the hospital within seven days of birth. Children in the control group did not receive any intervention. Parents were not blinded to allocation.ResultsThe mean difference in ASQ score at 12 months adjusted for age and prematurity was -0.7 points (BCG vs. control, 95% confidence interval; -3.7 to 2.4), p = 0.67, corresponding to an effect size of Cohen’s d = -0.015 (-0.082 to 0.052). The mean difference in ASQ score for premature children at 22 months was -7.8 points (-20.6 to 5.0, p = 0.23), d = -0.23 (-0.62 to 0.15).ConclusionsA negative non-specific effect of BCG vaccination at birth on psychomotor development was excluded in term children.

Trial Registration

ClinicalTrials.gov NCT01694108  相似文献   
994.
In this report we present the identification and analysis of two Bacillus subtilis genes, yklA and ykzA, which are homologous to the partially RpoS-controlled osmC gene from Escherichia coli. The yklA gene is expressed at higher levels in minimal medium than in rich medium and is driven by a putative vegetative promoter. Expression of ykzA is not medium dependent but increases dramatically when cells are exposed to stress and starvation. This stress-induced increase in ykzA expression is absolutely dependent on the alternative sigma factor ςB, which controls a large stationary-phase and stress regulon. ykzA is therefore another example of a gene common to the RpoS and ςB stress regulons of E. coli and B. subtilis, respectively. The composite complex expression pattern of the two B. subtilis genes is very similar to the expression profile of osmC in E. coli.  相似文献   
995.
An intriguing study shows that, in epidermal progenitor cells, circadian genes are expressed in successive waves that modulate responses to differentiation signals.  相似文献   
996.

Objective

To investigate whether changes in the plasma level of soluble urokinase plasminogen activator receptor (suPAR) can be used to monitor tuberculosis (TB) treatment efficacy.

Design

This prospective cohort study included 278 patients diagnosed with active pulmonary TB and followed throughout the 8-month treatment period.

Results

Mortality during treatment was higher in the highest inclusion quartile of suPAR (23%) compared to the lowest three quartiles (7%), the risk ratio being 3.1 (95% CI 1.65–6.07). No association between early smear conversion and subsequent mortality or inclusion suPAR was observed. After 1 and 2 months of treatment, an increase in suPAR compared to at diagnosis was associated with a Mortality Rate Ratio (MRR) of 4.5 (95%CI: 1.45–14.1) and 2.1 (95%CI 0.62–6.82), respectively, for the remaining treatment period.

Conclusions

The present study confirmed that elevated suPAR level at time of initiation of TB treatment is associated with increased risk of mortality. Furthermore, increased suPAR levels after one month of treatment was associated with increased risk of mortality during the remaining 7-month treatment period.  相似文献   
997.
998.

Background

Knowing which proteins exist in a certain organism or cell type and how these proteins interact with each other are necessary for the understanding of biological processes at the whole cell level. The determination of the protein-protein interaction (PPI) networks has been the subject of extensive research. Despite the development of reasonably successful methods, serious technical difficulties still exist. In this paper we present DomainGA, a quantitative computational approach that uses the information about the domain-domain interactions to predict the interactions between proteins.

Results

DomainGA is a multi-parameter optimization method in which the available PPI information is used to derive a quantitative scoring scheme for the domain-domain pairs. Obtained domain interaction scores are then used to predict whether a pair of proteins interacts. Using the yeast PPI data and a series of tests, we show the robustness and insensitivity of the DomainGA method to the selection of the parameter sets, score ranges, and detection rules. Our DomainGA method achieves very high explanation ratios for the positive and negative PPIs in yeast. Based on our cross-verification tests on human PPIs, comparison of the optimized scores with the structurally observed domain interactions obtained from the iPFAM database, and sensitivity and specificity analysis; we conclude that our DomainGA method shows great promise to be applicable across multiple organisms.

Conclusion

We envision the DomainGA as a first step of a multiple tier approach to constructing organism specific PPIs. As it is based on fundamental structural information, the DomainGA approach can be used to create potential PPIs and the accuracy of the constructed interaction template can be further improved using complementary methods. Explanation ratios obtained in the reported test case studies clearly show that the false prediction rates of the template networks constructed using the DomainGA scores are reasonably low, and the erroneous predictions can be filtered further using supplementary approaches such as those based on literature search or other prediction methods.  相似文献   
999.
Variable chlorophyll a (Chl a) fluorescence is composed of a photochemical and a thermal phases of similar amplitudes. The photochemical phase can be induced by a saturating single turnover flash (STF) and reflects the reduction of the Photosystem II (PS II) QA primary electron acceptor. The thermal phase requires multiple turnover flash (MTF) and is somehow related to the reduction of the plastoquinone (PQ) molecules. This article aimed to determine the relative contributions of the QB-bound and the free oxidized PQ molecules to the thermal phase of Chl a fluorescence. We thus measured the interactive effects of exogenous PQ (PQex), of an inhibitor (DCMU) acting at the QB site of PS II and of an artificial quencher, 2-methyl-1,4-naphtoquinone, on Chl a fluorescence levels induced by STF (FF) and MTF (FM) in spinach thylakoids. We observed that: (1) the incorporation of PQex in thylakoids stimulated photosynthetic electron transport but barely affected FF and FM in the absence of DCMU; (2) DCMU significantly increased the amplitude of FF but slightly quenched FM; (3) 2-methyl-1,4-naphtoquinone quenched FM to a larger-extent than FF; (4) DCMU increased the quenching effects of PQex on FF and FM and also, of methyl-1,4-naphtoquinone on FF. These results indicate that: (1) the QB-bound and the free PQ molecules contribute to about 56% and 25%, respectively, to the thermal phase Chl a fluorescence in dark-adapted thylakoids; and (2) the thermal phase of Chl a fluorescence is more susceptible than the photochemical phase to the non-photochemical quenching effect of oxidized quinones. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
1000.
The effect of temperature on filtration and ingestion rates ofSalpa fusiformis Cuvier was determined over the temperature range 13–22°C at a constant algal concentration. Filtration and ingestion rates increased with temperature up to an optimum (19.7 to 20.2°C) beyond which they decreased. Food assimilation for this salp species was determined while fed onPhaeodactylum tricornutum Bohlin orHymenomonas elongata Stein at different algal concentrations. The percent assimilation varied between 28 and 39% (mean: 32%) with the diatomP. tricornutum as food, and between 39 to 81% (mean: 64%) with the flagellateH. elongata. Assimilation did not seem to depend on the algal concentration but it was greater with the flagellate than with the diatom, the latter having a higher ash content.  相似文献   
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