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991.
Sułkowska-Ziaja Katarzyna Grabowska Karolina Apola Anna Kryczyk-Poprawa Agata Muszyńska Bożena 《Biotechnology letters》2021,43(5):1051-1061
Biotechnology Letters - This study analyzed the content of substances with cosmetologic properties in the extracts obtained from the mycelial cultures of Ganoderma applanatum, Laetiporus... 相似文献
992.
993.
Marta Vergnano Maja Mockenhaupt Natashia Benzian-Olsson Maren Paulmann Katarzyna Grys Satveer K. Mahil Charlotte Chaloner Ines A. Barbosa Suzannah August A. David Burden Siew-Eng Choon Hywel Cooper Alex A. Navarini Nick J. Reynolds Shyamal Wahie Richard B. Warren Andrew Wright 《American journal of human genetics》2021,108(4):757
994.
995.
The tumour suppressor L(3)mbt inhibits neuroepithelial proliferation and acts on insulator elements 总被引:1,自引:0,他引:1
In Drosophila, defects in asymmetric cell division often result in the formation of stem-cell-derived tumours. Here, we show that very similar terminal brain tumour phenotypes arise through a fundamentally different mechanism. We demonstrate that brain tumours in l(3)mbt mutants originate from overproliferation of neuroepithelial cells in the optic lobes caused by derepression of target genes in the Salvador-Warts-Hippo (SWH) pathway. We use ChIP-sequencing to identify L(3)mbt binding sites and show that L(3)mbt binds to chromatin insulator elements. Mutating l(3)mbt or inhibiting expression of the insulator protein gene mod(mdg4) results in upregulation of SWH pathway reporters. As l(3)mbt tumours are rescued by mutations in bantam or yorkie or by overexpression of Expanded, the deregulation of SWH pathway target genes is an essential step in brain tumour formation. Therefore, very different primary defects result in the formation of brain tumours, which behave quite similarly in their advanced stages. 相似文献
996.
Katarzyna Roguska Martin A Jünger Katja Köhler Irena Jevtov Hyungwon Choi Alexander Schmidt Alexey I Nesvizhskii Hugo Stocker Ernst Hafen Ruedi Aebersold Matthias Gstaiger 《Molecular systems biology》2011,7(1)
Genetic analysis in Drosophila melanogaster has been widely used to identify a system of genes that control cell growth in response to insulin and nutrients. Many of these genes encode components of the insulin receptor/target of rapamycin (InR/TOR) pathway. However, the biochemical context of this regulatory system is still poorly characterized in Drosophila. Here, we present the first quantitative study that systematically characterizes the modularity and hormone sensitivity of the interaction proteome underlying growth control by the dInR/TOR pathway. Applying quantitative affinity purification and mass spectrometry, we identified 97 high confidence protein interactions among 58 network components. In all, 22% of the detected interactions were regulated by insulin affecting membrane proximal as well as intracellular signaling complexes. Systematic functional analysis linked a subset of network components to the control of dTORC1 and dTORC2 activity. Furthermore, our data suggest the presence of three distinct dTOR kinase complexes, including the evolutionary conserved dTTT complex (Drosophila TOR, TELO2, TTI1). Subsequent genetic studies in flies suggest a role for dTTT in controlling cell growth via a dTORC1‐ and dTORC2‐dependent mechanism. 相似文献
997.
Jankowski J Juśkiewicz J Zduńczyk Z Smiecinska K Kwieciński P 《Archives of animal nutrition》2011,65(3):186-202
The effect of different concentrations of dietary Na from three Na salts (NaCl, NaHCO3 and Na2SO4) was assessed in two experiments carried out on broiler chickens aged from 1 to 35 days. In Exp. 1, diets were supplemented with 0.15, 0.20 and 0.25% Na, which increased the average Na content of the diets to 0.19, 0.24 and 0.30% respectively. In Exp. 2, the amounts of selected Na salts (NaCI and Na2SO4) were reduced and the estimated Na contents of experimental diets amounted to 0.10, 0.13, 0.15 and 0.19%. In view of the risk factors for the development of foot pad dermatitis, our aim was to find an optimum source of Na and to keep dietary Na intake at the minimum level sufficient to support normal growth and acceptable slaughter quality. The present results suggest that the amount of Na required for the undisturbed growth of broilers and adequate feed conversion is not less than 0.15% of additional Na in the starter period (1-14 d), and not less than 0.11% in the grower period (until day 35). Higher dietary Na levels did not lead to further production advantages, and were found to increase the moisture content of droppings. Dry matter concentration of excreta was also affected by Na source. In comparison with NaHCO3, Na2SO4 seemed to be a better alternative for NaCl. Na2SO4 also tended to surpass NaHCO3 as a dietary alternative for NaCl in terms of feed utilisation during the starter period. The applied additional Na levels (0.25 and 0.15%) and Na sources had no effect on the sensory profile and composition of breast meat. 相似文献
998.
Mohangoo AD Buitendijk SE Szamotulska K Chalmers J Irgens LM Bolumar F Nijhuis JG Zeitlin J;Euro-Peristat Scientific Committee 《PloS one》2011,6(11):e24727
Background
The first European Perinatal Health Report showed wide variability between European countries in fetal (2.6–9.1‰) and neonatal (1.6–5.7‰) mortality rates in 2004. We investigated gestational age patterns of fetal and neonatal mortality to improve our understanding of the differences between countries with low and high mortality.Methodology/Principal Findings
Data on 29 countries/regions participating in the Euro-Peristat project were analyzed. Most European countries had no limits for the registration of live births, but substantial variations in limits for registration of stillbirths before 28 weeks of gestation existed. Country rankings changed markedly after excluding deaths most likely to be affected by registration differences (22–23 weeks for neonatal mortality and 22–27 weeks for fetal mortality). Countries with high fetal mortality ≥28 weeks had on average higher proportions of fetal deaths at and near term (≥37 weeks), while proportions of fetal deaths at earlier gestational ages (28–31 and 32–36 weeks) were higher in low fetal mortality countries. Countries with high neonatal mortality rates ≥24 weeks, all new member states of the European Union, had high gestational age-specific neonatal mortality rates for all gestational-age subgroups; they also had high fetal mortality, as well as high early and late neonatal mortality. In contrast, other countries with similar levels of neonatal mortality had varying levels of fetal mortality, and among these countries early and late neonatal mortality were negatively correlated.Conclusions
For valid European comparisons, all countries should register births and deaths from at least 22 weeks of gestation and should be able to distinguish late terminations of pregnancy from stillbirths. After excluding deaths most likely to be influenced by existing registration differences, important variations in both levels and patterns of fetal and neonatal mortality rates were found. These disparities raise questions for future research about the effectiveness of medical policies and care in European countries. 相似文献999.
Spatial variations in phosphorus (P) fractionation, sediment geochemistry, and sorptive properties for P are assessed to test the hypothesis that these sediment properties vary within the lake and are governed by different land uses in the watershed. The dynamic equilibrium between P in sediment and water is investigated using sorption–desorption isotherms. Sediments in the littoral zone were rich in iron (Fe), aluminium (Al), and clay material in comparison to sediments from the lake proper and thus had better abilities to sorb and retain P. In the limnetic zone, there was an increasing abundance of primary minerals, and the fraction of apatite-P was high, while the level of total P was low. The amount of labile adsorbed P (LAP) in the littoral sediments varied because of contrasting land use in the sub-catchments draining into different parts of the lake. Sediments in areas where forest streams enter the lake contained significantly more LAP than sediments in areas impacted by agricultural influenced streams. Internal P loading from sediments predominantly originating from forest streams is mainly governed by sediment resuspension. The dominant P pool in sediments near the inlets of agriculturally influenced streams was non-apatite inorganic P, of which the Fe-bound is a potentially important source of P under anoxic conditions. 相似文献
1000.
Phytosterol—β-sitosterol promotes apoptosis in various cancer cells and inhibits their growth. Supplementation of cancer cells with this compound causes modifications in membrane composition, namely, substitution of cholesterol (Chol), decrease of sphingomyelin (SM) content and increase of ceramide (Cer) level. The aim of this work was to investigate the influence of partial replacement of cholesterol by plant sterol, substitution of sphingomyelin by ceramide and both these factors simultaneously on the properties of the monolayers composed of major lipids identified in breast cancer membranes, namely Chol/SM/GM3 mixtures. Brewster Angle Microcopy experiments and the analysis of the isotherms recorded during films compression and resulting parameters evidenced that β-sitosterol weakens the interactions between molecules, decreases films stability and condensation. The influence of ceramide on sterol/SM/GM3 films was reflected in strong modifications of their texture, however, the morphology of monolayer was determined by the structure of sterol present in the system. It was also found, that simultaneous replacement of 50 mol% of Chol and SM by phytosterol and Cer, respectively, induces lipids segregation, which is manifested in large diversity of phases observed in BAM images. To facilitate the analysis of the data collected for multicomponent monolayers, the properties of selected sterol/GM3, sterol/Cer, SM/GM3, Cer/GM3 binary films were also investigated. The obtained results evidenced that the studied herein modifications in the composition of Chol/SM/GM3 monolayer, reflecting compositional alterations induced by phytosterol in cancer membranes, strongly affect the organization of model system, therefore they should be considered in the studies on anticancer mechanism of β-sitosterol. 相似文献