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991.
Muñoz C López M Olivares M Pizarro F Arredondo M Araya M 《European cytokine network》2005,16(4):261-265
BACKGROUND: Copper (Cu) is an essential trace element for many biological processes including maintenance of both innate and acquired branches of immunity. OBJECTIVE: To measure the effect of copper supplementation on IL-2 and TNF-alpha production in subjects with lower and higher ceuloplasmin (Cp) values within normal range. DESIGN: Healthy adults (17 men and 16 women) with normal-low (low Cp) and normal-high Cp (high Cp) values were supplemented with 10 mg Cu/day (as CuSO(4)) during 2 months. METHOD: Before and after supplementation blood mononuclear cells were incubated in the absence or presence of phytohaemagglutinin or lipopolysaccharide for induction of IL-2 and TNF-alpha, respectively. The secretion of cytokines was measured by ELISA. Cu supplementation did not modify classical biochemical markers of Cu status. RESULTS: After supplementation, a significant increase in IL-2 production was found only in subjects with normal-low plasma Cp. Before and after Cu supplementation geometric mean and range +/- 1 SEM values were 1,566 (1,287-1,905) and 2,514 (2,159-2,927) pg/mL, respectively (two-way ANOVA for repeated measures: Cp level p < 0.001; time = NS; interaction Cp level and time p < 0.05). We did not observe changes in TNF-alpha production after Cu supplementation. CONCLUSIONS: Cu supplementation increased secretion of IL-2 and not TNF-alpha, which suggests an activation of proliferative but not inflammatory cytokines. These results support hypothesis that IL-2 may be a good indicator to identify a subgroup of individuals (polymorphism) who differs in Cu metabolism. 相似文献
992.
Radial glial cells defined and major intermediates between embryonic stem cells and CNS neurons 总被引:16,自引:0,他引:16
Radial glial cells have been identified as a major source of neurons during development. Here, we review the evidence for the distinct "glial" nature of radial glial cells and contrast these cells with their progenitors, the neuroepithelial cells. Recent results also suggest that not only during neurogenesis in vivo, but also during the differentiation of cultured embryonic stem cells toward neurons, progenitors with clear glial antigenic characteristics act as cellular intermediates. 相似文献
993.
The fascinating question of how the enormous diversity of neuronal and glial cells in the cerebral cortex is generated during development was recently discussed at a meeting on cortical development and stem cells in Greece. What emerged from this meeting is an equally fascinating answer, namely that precursor diversity at rather early stages of development anticipates later cell type diversity. 相似文献
994.
Czarniecka A Włoch J Jarzab M Krajewska J Kukulska A Roskosz J Puch Z Wróbel A Wollak M Turska M Stojcev Z Maka B 《Endokrynologia Polska》2005,56(5):758-765
The aim of the study was to analyze the clinical course and therapy in patients with differentiated thyroid carcinoma (DTC) diagnosed in Poland within the year 1995. The group of 478 patients with thyroid cancer (57.7% of all thyroid cancer cases diagnosed this year in Poland) was analyzed. Patients were diagnosed or treated in Maria Sk?odowska-Curie Memorial Cancer Center and Institute of Oncology, Gliwice Branch. Detailed analysis was performed in 352 patients with DTC who were treated by surgery. 292 patients (60%) received adjuvant radioiodine therapy. Hormonal (L-thyroxine) treatment was administered to all patients. In 37 patients (8.6%) local recurrence was observed. 10-year overall survival was 96.4% and disease-free survival was respectively 68%. The comparison of Polish data to analysis in German population published by Holtzer et al. (Cancer, 2000) was also performed in this study. We conclude that DTC therapy, currently recommended in our country, gives satisfactory results and that clinical outcome and therapeutic methods are similar both in Poland and Germany. 相似文献
995.
Olszanecka-Glinianowicz M Waluszek-Kończakowska I Zahorska-Markiewicz B Janowska J 《Endokrynologia Polska》2005,56(2):174-178
INTRODUCTION: TNF-alpha is one with mediators insulin resistance. Previous study showed, that in obesity there is an increased synthesis of TNF-alpha by fat cells and serum concentrations of TNF-alpha. The aim of present study was: 1. To assess of serum concentrations of TNF-alpha and TNF soluble receptors sTNFRs in obese women with diabetes type 2 and obese women without additional disease. 2. To assess possible association between of manner treatment of diabetes type 2 and serum concentrations of TNF-alpha and TNF soluble receptors. MATERIAL AND METHODS: The study group's involved 23 obese women with diabetes type 2 - group A (age 63.6 +/- 8.2 lat; BMI 32.7 +/- 3,9 kg/m2) in this 12 treated of derivatives of sulfonylurea (age 65.1 +/- 6.6 lat; BMI 32.0 +/- 3.4 kg/m2) - subgroup AI and 11 insulin treated (age 62.1 +/- 9.7 lat; BMI 33.4 +/- 4.4 kg/m2) - subgroup AII and 23 obese women without additional disease and without any pharmacological treatment - group B (age 36.6 +/- 10.9 lat; BMI 36.6 +/- 5.6 kg/m2). Body weight and height were measured, body mass index was calculated with formula. Serum concentrations of glucose was measured by enzymatic procedure. Serum concentrations of TNF-alpha and it's soluble receptors sTNFR1 and sTNFR2 was measured by ELISA. and sTNFR2 were significant decreased (respectively p <0,005 i p <0,001) in group A when compared to group B. There are not significant differences serum concentration of TNF-alpha and its soluble receptors between subgroups AI and AII. CONCLUSIONS: 1. In obese women with diabetes type 2 serum concentration of TNF-alpha increased and concentrations of its soluble receptors decreased when compared to obese without additional disease. 2. The treatment meaner of diabetes type 2 not influence of serum concentration of TNF-alpha and sTNFR1 but application of insulin maybe a cause increase activity sTNFR2. 相似文献
996.
Urbanowicz A Alejska M Formanowicz P Blazewicz J Figlerowicz M Bujarski JJ 《Journal of virology》2005,79(9):5732-5742
Previously we demonstrated frequent homologous crossovers among molecules of the RNA3 segment in the tripartite brome mosaic bromovirus (BMV) RNA genome (A. Bruyere, M. Wantroba, S. Flasinski, A. Dzianott, and J. J. Bujarski, J. Virol. 74:4214-4219, 2000). To further our knowledge about mechanisms of viral RNA genome variability, in this paper we have studied homologous recombination in BMV RNA1 and RNA2 components during infection. We have found that basal RNA-RNA crossovers could occur within coding regions of both RNAs, although recombination frequencies slightly varied at different RNA sections. In all cases, the frequencies were much lower than the rate observed for the intercistronic recombination hot spot in BMV RNA3. Probability calculations accounted for at least one homologous crossover per RNA molecule per replication cycle. In addition, we have demonstrated an efficient repair of mutations within the conserved 3' and 5' noncoding regions, most likely due to error-prone BMV RNA replication. Overall, our data verify that homologous crossovers are common events a during virus life cycle, and we discuss their importance for viral RNA genetics. 相似文献
997.
Hu B Han SY Wang X Ottey M Potoczek MB Dicker A Huebner K Wang Y 《Journal of cellular physiology》2005,202(2):518-523
Fragile Histidine Triad (Fhit) gene deletion, methylation, and reduced Fhit protein expression occur in about 70% of human epithelial tumors and, in some cancers, are clearly associated with tumor progression. Specific Fhit signal pathways have not been identified, although it has been shown that Fhit overexpression leads to apoptosis in many cancer cell lines. We report in this study that Fhit-/- cells derived from gene knockout mice show much stronger S and G2 checkpoint responses than their wild type counterparts. The strong checkpoint responses are regulated by the ATR/CHK1 pathway, which contributes to the radioresistance of Fhit-/- cells. These results indicate an association of Fhit gene inactivation with increased survival after DNA damage, which is related to the over-active checkpoints regulated by the ATR/CHK1 pathway. These results also suggest the potential effects of Fhit-dependent DNA damage response on tumor progression. 相似文献
998.
The cell biology of neurogenesis 总被引:19,自引:0,他引:19
During the development of the mammalian central nervous system, neural stem cells and their derivative progenitor cells generate neurons by asymmetric and symmetric divisions. The proliferation versus differentiation of these cells and the type of division are closely linked to their epithelial characteristics, notably, their apical-basal polarity and cell-cycle length. Here, we discuss how these features change during development from neuroepithelial to radial glial cells, and how this transition affects cell fate and neurogenesis. 相似文献
999.
Bayer M Fischer J Kremerskothen J Ossendorf E Matanis T Konczal M Weide T Barnekow A 《BMC cell biology》2005,6(1):15
Background
The small GTPase rab1a and its isoform rab1b are essential regulating components in the vesicle transport between the ER and the Golgi apparatus. Rab1 is thought to act as a molecular switch and can change between an active GTP-bound and an inactive GDP-bound conformation. To elucidate the function of rab1, several approaches have been established to isolate effector proteins, which interact with the activated conformation of rab1. To date p115, GM130, golgin-84 and MICAL have been identified as direct interacting partners. Together with rab1, these molecules are components of a protein complex, which mediates and regulates intracellular vesicle transport. 相似文献1000.
Miguel L Soares Seiki Haraguchi Maria-Elena Torres-Padilla Tibor Kalmar Lee Carpenter Graham Bell Alastair Morrison Christopher JA Ring Neil J Clarke David M Glover Magdalena Zernicka-Goetz 《BMC developmental biology》2005,5(1):1-11