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161.
Lopes-Lima M Bleher R Forg T Hafner M Machado J 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》2008,178(1):17-25
Early studies on the outer mantle epithelium (OME) cells of the freshwater bivalve Anodonta cygnea (Linnaeus, 1758) revealed high ionic calcium concentrations by electrophysiological methods and subsequently a high tendency
to reach an intracellular toxic condition. This toxicity could be neutralized by specific mechanisms in the cytosol of OME
cells of A. cygnea. The present immunocytochemistry studies of OME cells by light and transmission electron microscopy (TEM) clearly showed
a positive reaction of an antibody directed against the human plasma membrane Ca2+-ATPase 1 (PMCA-1) in the cytoplasm of OME cells. Also, western blot analysis of different fractions of OME cells with anti
human PMCA-1 and C28R2 antibodies confirmed the presence of a PMCA-like protein with an unusual topographical localization
and a molecular weight of only 70–80 kDa. These results lead us to speculate that this PMCA-like protein is distributed either
in the plasma membrane or in the entire cytosol, where it eventually regulates intracellular calcium levels. Interestingly,
the antibody reactions showed seasonal variations, being highest in OME samples prepared during summer when A. cygnea live under natural acidosis and absent in samples taken in winter conditions, which is in accordance with the seasonal variation
of shell calcification rates. During winter, PMCA-1 antibody reaction was also detected in OME cells of animals kept only
under experimentally induced acidosis conditions. Therefore, we assume that a functional role for this PMCA-like protein in
the intracellular calcium regulation of OME cells during the mineralization of the shells of A. cygnea can be speculated. 相似文献
162.
Greubel C Hable V Drexler GA Hauptner A Dietzel S Strickfaden H Baur I Krücken R Cremer T Friedl AA Dollinger G 《Radiation and environmental biophysics》2008,47(4):415-422
Several proteins are known to form foci at DNA sites damaged by ionizing radiation. We study DNA damage response by immunofluorescence
microscopy after microirradiation of cells with energetic ions. By using microirradiation, it is possible to irradiate different
regions on a single dish at different time-points and to differentiate between cells irradiated earlier and later. This allows
to directly compare immunofluorescence intensities in both subsets of cells with little systematic error because both subsets
are cultivated and stained under identical conditions. In addition, by using irradiation patterns such as crossing lines,
it is possible to irradiate individual cells twice and to differentiate between immunofluorescence signals resulting from
the cellular response to the earlier and to the later irradiation event. Here, we describe the quantitative evaluation of
immunofluorescence intensities after sequential irradiation. 相似文献
163.
Gutiérrez-Miceli FA García-Gómez RC Rincón Rosales R Abud-Archila M María Angela OL Cruz MJ Dendooven L 《Bioresource technology》2008,99(14):6174-6180
Leachate from vermicomposting contains large amounts of plant nutrients and can be used as liquid fertilizer, but normally diluted to avoid plant damage. The amount of nutrients applied is thus reduced so that an additional fertilizer is required. We investigated how dilution of vermicompost leachate combined with different concentrations of NPK triple 17 fertilizer, and polyoxyethylene tridecyl alcohol as dispersant and polyethylene nonylphenol as adherent to increase efficiency of fertilizer uptake, affected sorghum plant development. The vermicomposting leachate with pH 7.8 and electrolytic conductivity 2.6 dS m(-1), contained 834 mg K(+) l(-1), 247 mg NO(3)(-)l(-1) and 168 mg PO(4)(3-) l(-1), was free of pathogens and resulted in a 65 % germination index. Vermicompost leachate can be used as liquid fertilizer for the cultivation of sorghum without dilution and mixed with 140-170 g l(-1) of NPK triple 17 fertilizer and 2-3 ml(-1) of dispersant and 0-1 ml l(-1) adherent. It was found that vermicompost leachate stimulated plant development, but fertilization with NPK was required for maximum growth. 相似文献
164.
Alexandru-Lucian Curtu Reiner Finkeldey Oliver Gailing 《Plant Molecular Biology Reporter》2004,22(4):339-346
Microsatellites (simple sequence repeats [SSRs]) are highly variable molecular markers that are a rich and readily assayed
source of variation for population genetic studies. Cross-amplification between closely related species is possible when there
are no (or few) sequence differences in the primer binding sites. The occurrence of nonhomologous fragments of the same size
(size homoplasy) is a contraint of microsatellites. Size homoplasy can be caused by insertions/deletions (indels) in SSR flanking
regions. We found that size variation in locus ssrQZAG9 is due to different repeat numbers of the SSR motifs but also to indels
in SSR flanking regions. Indels were found within species belonging to sectionsRobur andCerris of genusQuercus and also between species of the 2 sections. In sectionRobur (Quercis robur L.,Quercus petraea [Matt.] Liebl.,Quercus pubescens Willd.), we detected rare alleles with an indel of 57 bp or 62 bp followed by a smaller indel of 12 bp in the SSR flanking
regions. These alleles show a size range overlapping with that of alleles amplified inQuercus cerris L. (sectionCerris). Multiple alignments with sequences of sectionRobur revealed the same SSR repeat motif but multiple indels in SSR flanking regions inQ. cerris. We discuss the effects of size homoplasy of SSR loci for the study of interspecific gene flow and on estimates of population
differentiation. 相似文献
165.
Polymorphisms within the C-Reactive Protein (CRP) Promoter Region Are Associated with Plasma CRP Levels
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Christopher S. Carlson Shelley Force Aldred Philip K. Lee Russell P. Tracy Stephen M. Schwartz Mark Rieder Kiang Liu O. Dale Williams Carlos Iribarren E. Cora Lewis Myriam Fornage Eric Boerwinkle Myron Gross Cashell Jaquish Deborah A. Nickerson Richard M. Myers David S. Siscovick Alexander P. Reiner 《American journal of human genetics》2008,82(1):251
166.
Reversible interruption of Giardia lamblia cyst wall protein transport in a novel regulated secretory pathway 总被引:2,自引:1,他引:1
To survive in the environment and infect a new host, Giardia lamblia secretes an extracellular cyst wall using a poorly understood pathway. The two cyst wall proteins (CWPs) form disulphide-bonded heterodimers and are exported via novel encystation-specific secretory vesicles (ESVs). Exposure of eukaryotic cells to dithiothreitol (DTT) blocks the formation of disulphide bonds in nascent proteins that accumulate in the endoplasmic reticulum (ER) and induces an unfolded protein response (UPR). Proteins that have exited the ER are not susceptible. Exposure to DTT inhibits ESV formation by > 85%. Addition of DTT to encysting cells causes rapid ( t 1/2 < 10 min), reversible disappearance of ESVs, correlated with reduction of CWPs to monomers and reformation of CWP oligomers upon removal of DTT. Neither CWPs nor ESVs are affected by mercaptoethanesulphonic acid, a strong reducing agent that does not penetrate cells. DTT does not inhibit the overall protein secretory pathway, and recovery does not require new protein synthesis. We found evidence of protein disulphide isomerases in the ESV and the surface of encysting cells, in which they may catalyse initial CWP folding and recovery from DTT. This is the first suggestion of non-CWP proteins in ESVs and of enzymes on the giardial surface. DTT treatment did not stimulate a UPR, suggesting that Giardia may have diverged before the advent of this conserved form of ER quality control. 相似文献
167.
A C Mullen A S Hutchins A V Villarino H W Lee F A High N Cereb S Y Yang X Hua S L Reiner 《Current biology : CB》2001,11(21):1695-1699
168.
Gwendlyn Kollmorgen Birgit Bossenmaier Gerhard Niederfellner Hans-Ulrich H?ring Reiner Lammers 《PloS one》2012,7(12)
Cub domain containing protein 1 (CDCP1) is strongly expressed in tumors derived from lung, colon, ovary, or kidney. It is a membrane protein that is phosphorylated and then bound by Src family kinases. Although expression and phosphorylation of CDCP1 have been investigated in many tumor cell lines, the CDCP1 features responsible for transformation have not been fully evaluated. This is in part due to the lack of an experimental system in which cellular transformation depends on expression of exogenous CDCP1 and Src. Here we use retrovirus mediated co-overexpression of c-Src and CDCP1 to induce focus formation of NIH3T3 cells. Employing different mutants of CDCP1 we show that for a full transformation capacity, the intact amino- and carboxy-termini of CDCP1 are essential. Mutation of any of the core intracellular tyrosine residues (Y734, Y743, or Y762) abolished transformation, and mutation of a palmitoylation motif (C689,690G) strongly reduced it. Src kinase binding to CDCP1 was not required since Src with a defective SH2 domain generated even more CDCP1 dependent foci whereas Src myristoylation was necessary. Taken together, the focus formation assay allowed us to define structural requirements of CDCP1/Src dependent transformation and to characterize the interaction of CDCP1 and Src. 相似文献
169.
Hermann-Josef Egger Josef Reiner Gerhard Spiteller 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1978,145(3):359-369
Urine steroid profiles of hirsute womenSteroid profiles of women suffering from idiopathic hirsutism show in more than 50% of the cases a 10–100 fold increase in the excretion of dehydroepiandrosterone (DHEA) compared with normal values.The excretion of DHEA was reduced much more than that of other 17-ketosteroids if the adrenals (NNR) were suppressed by dexamethasone (DXM). Within one week they reached values at the compound noise level of the gas chromatograms. If the ovaries were stimulated with human chorionic gonadotropin during continued suppression of the NNR with DXM no increase of DHEA could be detected. 相似文献
170.