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91.
The aim of this study is an analysis of the possible adaptive consequences of delivery of low birth weight infants. We attempt to reveal the cost and benefit components of bearing small children, estimate the chance of the infants’ survival, and calculate the mothers’ reproductive success. According to life-history theory, under certain circumstances mothers can enhance their lifetime fitness by lowering the rate of investment in an infant and/or enhancing the rate of subsequent births. We assume that living in a risky environment and giving birth to a small infant may involve a shift from qualitative to quantitative production of offspring. Given high infant mortality rates, parents will have a reproductive interest in producing a relatively large number of children with a smaller amount of prenatal investment. This hypothesis was tested among 650 Gypsy and 717 non-Gypsy Hungarian mothers. Our study has revealed that 23.8% of the Gypsy mothers had low birth weight (<2,500 g) children, whose mortality rate is very high. These mothers also had more spontaneous abortions and stillbirths than those with normal weight children. As a possible response to these reproductive failures, they shortened birth spacing, gaining 2–4 years across their reproductive lifespan for having additional children. Because of the relatively short interbirth intervals, by the end of their fertility period, Gypsy mothers with one or two low birth weight infants have significantly more children than their ethnic Hungarian counterparts. They appear to compensate for handicaps associated with low birth weights by having a larger number of closely spaced children following the birth of one or more infants with a reduced probability of survival. The possible alternative explanations are discussed, and the long-term reproductive benefits are estimated for both ethnic groups. 相似文献
92.
Servettaz A Guilpain P Camoin L Mayeux P Broussard C Tamby MC Tamas N Kaveri SV Guillevin L Mouthon L 《Proteomics》2008,8(5):1000-1008
In order to identify target antigens of anti-endothelial cell (anti-EC) antibodies (AECA) in healthy individuals, we have used a proteomic approach combining 2-DE and immunoblotting. Whole cell protein extracts obtained from human umbilical vein EC (HUVEC) cultures were used as a source of antigens. Serum IgG from 12 healthy blood donors were tested at a concentration of 200 microg/mL. Targeted spots were identified by MS. The HUVEC proteome was composed of 884 protein spots. Among these, 61 +/- 25.8 (mean +/- SD) spots were recognized by serum IgG from healthy individuals, with marked differences from one individual to another. Among these spots, 11 were recognized by serum IgG from all healthy individuals tested. These spots corresponded to six different proteins with several spots corresponding to different isoforms of the same protein. Target antigens were: cytoskeletal proteins (beta-actin, alpha-tubulin, and vimentin); glycolytic enzymes (glucose-3-phosphate-deshydrogenase and alpha-enolase); and prolyl-4-hydroxylase beta subunit, a member of the disulfide isomerase family. This study shows that the repertoire of IgG AECA is heterogeneous among healthy individuals. IgG from all of the healthy individuals tested recognized a restricted set of highly conserved ubiquitous proteins playing key roles in cell biology and maintenance of homeostasis. 相似文献
93.
Phosphoinositides account for only a tiny fraction of cellular phospholipids but are extremely important in the regulation of the recruitment and activity of many signaling proteins in cellular membranes. Phosphatidylinositol (PtdIns) 4-kinases generate PtdIns 4-phosphate, the precursor of important regulatory phosphoinositides but also an emerging regulatory molecule in its own right. The four mammalian PtdIns 4-kinases regulate a diverse array of signaling events, as well as vesicular trafficking and lipid transport, but the mechanisms by which their lipid product PtdIns 4-phosphate controls these processes is only beginning to unfold. 相似文献
94.
Estate M. Sokhadze Allan Tasman Rebecca Tamas Rif S. El-Mallakh 《Applied psychophysiology and biofeedback》2011,36(1):1-13
There appears to be a significant disconnect between symptomatic and functional recovery in bipolar disorder (BD). Some evidence
points to interepisode cognitive dysfunction. We tested the hypothesis that some of this dysfunction was related to emotional
reactivity in euthymic bipolar subjects may effect cognitive processing. A modification of emotional gender categorization
oddball task was used. The target was gender (probability 25%) of faces with negative, positive, and neutral emotional expression.
The experiment had 720 trials (3 blocks × 240 trials each). Each stimulus was presented for 150 ms, and the EEG/ERP responses
were recorded for 1,000 ms. The inter-trial interval was varied in 1,100–1,500 ms range to avoid expectancy effects. Task
took about 35 min to complete. There were 9 BD and 9 control subjects matched for age and gender. Reaction time (RT) was globally
slower in BD subjects. The centro-parietal amplitudes at N170 and N200, and P200 and P300 were generally smaller in the BD
group compared to controls. Latency was shorter to neutral and negative targets in BD. Frontal P200 amplitude was higher to
emotional negative facial non-targets in BD subjects. The frontal N200 in response to positive facial emotion was less negative
in BD subjects. The frontal P300 of BD subjects was lower to emotionally neutral targets. ERP responses to facial emotion
in BD subjects varied significantly from normal controls. These variations are consistent with the common depressive symptomology
seen in long term studies of bipolar subjects. 相似文献
95.
Sidhu G Li W Laryngakis N Bishai E Balla T Southwick F 《The Journal of biological chemistry》2005,280(12):11379-11386
Motile nonmuscle cells concentrate phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3) and phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2) in areas of new actin filament assembly. There is great interest in assessing the in vivo functional significance of these phosphoinositides, and we have used Listeria monocytogenes to explore the contribution of PtdIns(3,4,5)P3 and PtdIns(4,5)P2 to its actin-based motility. In Listeria-infected PtK2 cells Akt-pleckstrin homology (PH)-green fluorescent protein (GFP) and phospholipase C delta (PLC delta)-PH-GFP both first concentrate at the front of motile Listeria, subsequently surrounding the bacterium and then concentrating in the actin filament tail. Surprisingly, Listeria ActA mutant strains lacking the putative phosphoinositide binding site are also able to concentrate these probes. Reduction of available PtdIns(3,4,5)P3 by expression of Akt-PH-GFP and available PtdIns(4,5)P2 by expression of PLC delta-PH-GFP both significantly slow Listeria actin-based movement. Treatment of cells with the PI 3-kinase inhibitor, LY294002, dissociates Akt-PH but not PLC delta-PH, from the bacterial surface and cell membranes, and results in near complete inhibition of Listeria actin-based motility and filopod formation. Removal of LY294002 results in rapid and full recovery of Akt-PH localization, Listeria actin-based motility, and filopod formation. These findings suggest that PtdIns(4,5)P2 is concentrated at the surface of Listeria and serves as the substrate for PtdIns(3,4,5)P3 production, indicating a central role for PI 3-kinases in Listeria intracellular actin-based motility and filopod formation. 相似文献
96.
Xinshou Ouyang Sheng-Na Han Ji-Yuan Zhang Evangelos Dioletis Balazs Tamas Nemeth Pal Pacher Dechun Feng Ramon Bataller Joaquin Cabezas Peter Stärkel Joan Caballeria Rebecca LePine Pongratz Shi-Ying Cai Bernd Schnabl Rafaz Hoque Yonglin Chen Wei-hong Yang Irma Garcia-Martinez Wajahat Zafar Mehal 《Cell metabolism》2018,27(2):339-350.e3
97.
98.
Rita Skoda-F ldes Zita Cs kai L szl Koll r G bor Szalontai Judit Horv th Zolt n Tuba 《Steroids》1995,60(12):786-790
17-Iodo-Δ16 steroids undergo selective dimerization and carbonylative dimerization in the presence of palladium catalysts in dimethylformamide which result in 16–17′-coupled dienes and 17-carboxylic anhydrides, respectively. Moderate to good yields have been obtained for both types of dimers. 相似文献
99.
An evolutionary theory of socialization suggests that children from father-absent families will mature earlier, and form less-stable pair bonds, compared with those from father-present families. Using a sample of about 1,000 persons the recent study focuses on elements of father-absent children’s behavior that could be better explained by a Darwinian approach than by rival social science theories. As a result of their enhanced interest in male competition, father-absent boys were found to engage in rule-breaking behavior more intensively than father-present boys. Compared with father-present children, adolescents from widowed households (both boys and girls) showed a higher intensity of various kinds of noncompliant behavior, which can be linked to their earlier maturation. School attendance, age at marriage, and marital success proved to be influenced by the children’s early family experiences, governed by adapted evolutionary strategies. Father-absent daughters conceived more children than those whose fathers were present during their childhood. As evolutionary theory predicts, reproductive behavior of individuals from divorced households differed from that of individuals who grew up in widowed households. Finally, the strong correlation found between spontaneous abortion/stillbirths and family arrangement indicates that father absence has certain direct impacts on the neurohormonal processes of child development. 相似文献
100.
T. Kulinski Anders B. A. Wennerberg R. Rigler Stephen W. Provencher M. Pooga Ü. Langel Tamas Bartfai 《European biophysics journal : EBJ》1997,26(2):145-154
The structural dynamics of the flexible neuropeptide galanin in solution were studied by Förster resonance energy transfer measurements at different temperatures by time-resolved fluorescence spectroscopy to determine its conformational heterogeneity. Endogenous tryptophan at position 2 acted as the fluorescent donor and the non fluorescent acceptor dinitrophenyl or the fluorescent acceptor dansyl were selectively attached to lysine 25 in porcine galanin. The coexistence of different structures of the neuropeptide galanin in trifluoroethanol solution was revealed by the model independent analysis of the distribution of relaxation times from the time-resolved resonance energy transfer data. Multiple conformational states are reflected by distinct end-to-end distance populations. The conformations differ in mean donor-acceptor distance by about 15 Å, and are consistent with the extended and folded backbone conformations of two α-helical regions separated by a flexible hinge. The effect that the labelling of galanin has on binding to the receptor was also evaluated. DNP-galanin showed the same high affinity to galanin receptors as unlabelled galanin, whereas DNS-galanin had significantly reduced affinity. 相似文献