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991.
Diaz D Chara L Chevarria J Carballido J Esteban E Navas V Monserrat J Prieto A de la Hera A Alvarez-Mon M 《Cancer immunology, immunotherapy : CII》2009,58(2):235-245
The peripheral blood lymphocytes of eight patients with metastatic renal cell carcinoma, and of eight healthy volunteers were
analyzed by four-color flow cytometry to characterize the immunophenotypic alterations manifested, determine the prevalence
of lymphocyte apoptosis, and detect evidence of the systemic effect of inhaled IL-2. The T, B and NK lymphocytes of untreated
patients were found to have undergone profound changes characterized by an increase in susceptibility to both spontaneous
and mitogen-induced ex vivo apoptosis, a modified distribution of the main lymphocyte populations in the peripheral blood,
and alterations in activation status. An increase in the proportion of regulatory T cells was also seen in these patients.
Treatment with inhaled IL-2, however, normalized the rate of apoptosis in all the lymphocyte subpopulations studied, as well
as their distribution and activation status. These findings demonstrate that inhaled IL-2 has systemic immunomodulatory effects. 相似文献
992.
Susana Delgado M. Carmen Collado Leonides Fernández Juan M. Rodríguez 《Current microbiology》2009,59(1):59-64
Lactational Raynaud’s syndrome may be misdiagnosed as infectious mastitis on the basis of the breast pain. The objective of
this work was to elucidate if microbiological analysis of milk may contribute to the differentiation of both conditions. Ten
lactating women clinically diagnosed by Spanish lactation consultants were included in the study. Of these, five suffered
from mastitis and the remaining five suffered from Raynaud’s syndrome. Breast milk samples were inoculated on diverse culture
media. Seventy isolates were selected and identified by 16S rDNA PCR sequencing. Parallel, PCR-DGGE and quantitative real-time
PCR were used to assess the presence of bacterial DNA in the samples. Neither bacteria nor yeasts could be detected in the
milk samples provided by the women suffering from Raynaud’s syndrome. In contrast, large numbers of bacteria were isolated
from those with infectious lactational mastitis. Globally, the levels of bacterial DNA were significantly higher in the milk
of mastitis-suffering women. Bacteriological analysis of milk can be an useful tool to facilitate the differential diagnosis
between the infectious mastitis and Raynaud’s syndrome during lactation. 相似文献
993.
Patrícia Nardin Lucas Tortorelli André Quincozes-Santos Lúcia Maria V. de Almeida Marina C. Leite Ana Paula Thomazi Carmem Gottfried Susana T. Wofchuk Rosario Donato Carlos-Alberto Gonçalves 《Neurochemical research》2009,34(9):1603-1611
Hippocampal slices have been widely used to investigate electrophysiological and metabolic neuronal parameters, as well as
parameters of astroglial activity including protein phosphorylation and glutamate uptake. S100B is an astroglial-derived protein,
which extracellularly plays a neurotrophic activity during development and excitotoxic insult. Herein, we characterized S100B
secretion in acute hippocampal slices exposed to different concentrations of K+ and Ca2+ in the extracellular medium. Absence of Ca2+ and/or low K+ (0.2 mM KCl) caused an increase in S100B secretion, possibly by mobilization of internal stores of Ca2+. In contrast, high K+ (30 mM KCl) or calcium channel blockers caused a decrease in S100B secretion. This study suggests that exposure of acute
hippocampal slices to low- and high-K+ could be used as an assay to evaluate astrocyte activity by S100B secretion: positively regulated by low K+ (possibly involving mobilization of internal stores of Ca2+) and negatively regulated by high-K+ (likely secondary to influx of K+). 相似文献
994.
Eduardo Cires Candela Cuesta Elena L. Peredo María Ángeles Revilla José Antonio Fernández Prieto 《Plant Systematics and Evolution》2009,281(1-4):193-208
Ranunculus parnassifolius is an orophilous plant distributed throughout Central and Southwestern Europe (Alps, Pyrenees and Cantabrian Mountains). Its evolutionary history and taxonomy are often complicated, having been little studied before now. The purpose of this article is to present flow cytometry measurements and multivariate morphometric analyses to ascertain cytotype distribution patterns and the morphological differentiation of R. parnassifolius s.l. from calcareous screes in the Northwest of Spain. DNA ploidy level and morphometric analysis were determined for plants of R. parnassifolius s.l. using flow cytometry (112 individuals) and multivariate analysis (152 individuals). Specimens were collected in eight localities in the Northwest of the Iberian Peninsula. Different sample preservation methods (fresh, frozen, and herbarium specimens) were employed as well as the use of various buffers and internal standards, in order to test the reproducibility of DNA flow cytometry. Three ploidy levels were detected in the study area (diploid, tetraploid, and pentaploid), and mixed-cytotype populations were also found. The mean nuclear DNA content of the R. parnassifolius group ranged from 7.43 ± 0.185 to 7.63 ± 0.339 pg/2C in diploids and from 15.09 ± 0.161 to 15.85 ± 0.587 pg/2C in tetraploids. The analysis of the monoploid genome sizes (1Cx) did not reveal a clear difference among cytotypes. These results suggest low intraspecific variation, at least among the populations studied. In addition, a comparison of different DNA reference standards was conducted. A new value for the chicken genome size was used as internal reference standard (2C = 3.14 ± 0.155 pg), with similar results found using both animal and plant standards (Pisum sativum and Solanum lycopersicum). Finally, herbarium vouchers and frozen tissue were proved to be suitable for DNA ploidy level measurements. This study provided a first assessment of C values in the R. parnassifolius group using flow cytometry. The weak morphological distinction of the cytotypes and the existence of mixed-cytotype populations in the Northwest of Spain are reported here for the first time. The different distribution pattern of the two cytotypes is discussed. 相似文献
995.
Reema Alag Nagakumar Bharatham Aiping Dong Tanya Hills Amaravadhi Harikishore Anissa Anindya Widjaja Susana Geifman Shochat Raymond Hui Ho Sup Yoon 《Protein science : a publication of the Protein Society》2009,18(10):2115-2124
Plasmodium falciparum FK506‐binding protein 35 (PfFKBP35) that binds to FK506 contains a conserved tetratricopeptide repeat (TPR) domain. Several known TPR domains such as Hop, PPP5, CHIP, and FKBP52 are structurally conserved and are able to interact with molecular chaperones such as Hsp70/Hsp90. Here, we present the crystal structure of PfFKBP35‐TPR and demonstrate its interaction with Hsp90 C‐terminal pentapeptide (MEEVD) by surface plasmon resonance and nuclear magnetic resonance spectroscopy‐based binding studies. Our sequence and structural analyses reveal that PfFKBP35 is similar to Hop and PPP5 in possessing all the conserved residues which are important for carboxylate clamping with Hsp90. Mutational studies were carried out on positively charged clamp residues that are crucial for binding to carboxylate groups of aspartate, showing that all the mutated residues are important for Hsp90 binding. Molecular docking and electrostatic calculations demonstrated that the MEEVD peptide of Hsp90 can form aspartate clamp unlike FKBP52. Our results provide insightful information and structural basis about the molecular interaction between PfFKBP35‐TPR and Hsp90. 相似文献
996.
Many reactions within the cell occur only in specific intracellular regions. Such local reaction networks give rise to microdomains of activated signaling components. The dynamics of microdomains can be visualized by live cell imaging. Computational models using partial differential equations provide mechanistic insights into the interacting factors that control microdomain dynamics. The mathematical models show that, for membrane-initiated signaling, the ratio of the surface area of the plasma membrane to the volume of the cytoplasm, the topology of the signaling network, the negative regulators, and kinetic properties of key components together define microdomain dynamics. Thus, patterns of locally restricted signaling reaction systems can be considered an emergent property of the cell. 相似文献
997.
998.
Nuno Pedroso Ana C. Matias Luísa Cyrne Fernando Antunes Carlos Borges Rui Malhó Rodrigo F.M. de Almeida Enrique Herrero H. Susana Marinho 《Free radical biology & medicine》2009,46(2):289-298
In Saccharomyces cerevisiae, the rate of hydrogen peroxide (H2O2) diffusion through the plasma membrane decreases during adaptation to H2O2 by a still unknown mechanism. Here, adaptation to H2O2 was observed to modulate rapidly the expression of genes coding for enzymes involved in ergosterol and lipid metabolism. Adaptation to H2O2 also alters plasma membrane lipid composition. The main changes were the following: (a) there was a decrease in oleic acid (30%) and in the ratio between unsaturated and saturated long-chain fatty acids; (b) the phosphatidylcholine:phosphatidylethanolamine ratio increased threefold; (c) sterol levels were unaltered but there was an increased heterogeneity of sterol-rich microdomains and increased ordered domains; (d) the levels of the sterol precursor squalene increased twofold, in agreement with ERG1 gene down-regulation; and (e) C26:0 became the major very long chain fatty acid owing to an 80% decrease in 2-hydroxy-C26:0 levels and a 50% decrease in C20:0 levels, probably related to the down-regulation of fatty acid elongation (FAS1, FEN1, SUR4) and ceramide synthase (LIP1, LAC1) genes. Therefore, H2O2 leads to a reorganization of the plasma membrane microdomains, which may explain the lower permeability to H2O2, and emerges as an important regulator of lipid metabolism and plasma membrane lipid composition. 相似文献
999.
John Panepinto Kazimierz Komperda Susana Frases Yoon-Dong Park Julianne T. Djordjevic Arturo Casadevall Peter R. Williamson 《Molecular microbiology》2009,71(5):1165-1176
The cell wall of pathogenic fungi such as Cryptococcus neoformans , provides a formidable barrier to secrete virulence factors that produce host cell damage. To study secretion of virulence factors to the cell periphery, sec6 RNAi mutant strains of C. neoformans were tested for virulence factor expression. The studies reported here show that SEC6 RNAi mutant strains were defective in a number of virulence factors including laccase, urease as well as soluble polysaccharide and demonstrated attenuated virulence in mice. Further analysis by transmission electron microscopy detected the production of abundant extracellular exosomes in wild-type strains containing empty plasmid, but a complete absence in the i SEC6 strain. In addition, a green fluorescent protein–laccase fusion protein demonstrated aberrant localization within cytoplasmic vesicles in i SEC6 strains. In contrast, i SEC6 strains retained normal growth at 37°C, as well as substantially normal capsule formation, phospholipase activity and total secreted protein. These results provide the first molecular evidence for the existence of fungal exosomes and associate these vesicles with the virulence of C. neoformans . 相似文献
1000.