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121.
Marcotullio MC Pagiotti R Maltese F Oball-Mond Mwankie GN Hoshino T Obara Y Nakahata N 《Bioorganic & medicinal chemistry》2007,15(8):2878-2882
Two new cyathane diterpenes, cyrneine C (4) and D (5), were isolated from the mushroom Sarcodon cyrneus, along with previously isolated cyrneine A, B and glaucopine C. The structures of the novel diterpenoids were determined by the analysis of spectroscopic data. Effects of the cyrneines and glaucopine C on the NGF gene expression in 1321N1 cells and on neurite outgrowth on PC12 cells were evaluated. 相似文献
122.
Mantegani P Piana F Galli L Scarpellini P Codecasa L Lazzarin A Cirillo D Fortis C 《The new microbiologica》2007,30(3):291-294
Identification of individuals with a tuberculosis infection is a very important element for the control of tuberculosis. The currently used tuberculin skin test has poor sensitivity and specificity. Recently, an important advance in tuberculosis diagnosis occurred with the development of in vitro T cell-based IFN-gamma release assays. The aim of this study was to compare a RD1-based in-house ELISPOT-IFN-gamma assay with a commercial (T-SPOT.TB) assay for the diagnosis of tuberculosis infection. The results showed an almost complete concordance between the two assays, confirming that our restricted but highly selected pool of peptides is sufficient to detect tuberculosis infection. 相似文献
123.
Bottini M D'Annibale F Magrini A Cerignoli F Arimura Y Dawson MI Bergamaschi E Rosato N Bergamaschi A Mustelin T 《International journal of nanomedicine》2007,2(2):227-233
To enhance diagnostic or therapeutic efficacy, novel nanomaterials must be engineered to function in biologically relevant environments, be visible by conventional fluorescent microscopy, and have multivalent loading capacity for easy detection or effective drug delivery. Here we report the fabrication of silica nanoparticles doped with quantum dots and superficially functionalized with amino and phosphonate groups. The amino groups were acylated with a water-soluble biotin-labeling reagent. The biotinylated nanoparticles were subsequently decorated with neutravidin by exploiting the strong affinity between neutravidin and biotin. The resultant neutravidin-decorated fluorescent silica nanoparticles stably dispersed under physiological conditions, were visible by conventional optical and confocal fluorescent microscopy, and could be further functionalized with macromolecules, nucleic acids, and polymers. We also coated the surface of the nanoparticles with biotinylated mouse anti-human CD3 (alphaCD3). The resultant fluorescent nanoassembly was taken up by Jurkat T cells through receptor-mediated endocytosis and was partially released to lysosomes. Thus, quantum dot-doped silica nanoparticles decorated with neutravidin represent a potentially excellent scaffold for constructing specific intracellular nanoprobes and transporters. 相似文献
124.
MicroRNA-133 controls cardiac hypertrophy 总被引:23,自引:0,他引:23
125.
Periostin induces proliferation of differentiated cardiomyocytes and promotes cardiac repair 总被引:8,自引:0,他引:8
Kühn B del Monte F Hajjar RJ Chang YS Lebeche D Arab S Keating MT 《Nature medicine》2007,13(8):962-969
Adult mammalian hearts respond to injury with scar formation and not with cardiomyocyte proliferation, the cellular basis of regeneration. Although cardiogenic progenitor cells may maintain myocardial turnover, they do not give rise to a robust regenerative response. Here we show that extracellular periostin induced reentry of differentiated mammalian cardiomyocytes into the cell cycle. Periostin stimulated mononucleated cardiomyocytes to go through the full mitotic cell cycle. Periostin activated alphaV, beta1, beta3 and beta5 integrins located in the cardiomyocyte cell membrane. Activation of phosphatidylinositol-3-OH kinase was required for periostin-induced reentry of cardiomyocytes into the cell cycle and was sufficient for cell-cycle reentry in the absence of periostin. After myocardial infarction, periostin-induced cardiomyocyte cell-cycle reentry and mitosis were associated with improved ventricular remodeling and myocardial function, reduced fibrosis and infarct size, and increased angiogenesis. Thus, periostin and the pathway that it regulates may provide a target for innovative strategies to treat heart failure. 相似文献
126.
Balbis E Patriarca S Furfaro AL Cottalasso D Pronzato MA Carlier P Botta F Marinari UM Fontana L Traverso N 《Redox report : communications in free radical research》2007,12(1):59-62
Results on oxidative markers during ageing are not consistent throughout the scientific literature; however, successful ageing may depend on better ability to cope with oxidative stress. A previous study of ours showed that successful ageing could actually be related to enhanced response to oxidatively modified proteins. In this study, a healthy nonagenarian population (OVER-90) was examined for various blood oxidative biomarkers and compared with a healthy population of blood donors (age range, 23-66 years). Blood glutathione, both total (tGSH) and oxidised (GSSG), and total plasmatic antioxidant status were maintained in the OVER-90 at a level similar to the control population. Sulphydryl (sulfhydryl) groups and glutathione peroxidase (GPx) were instead decreased. The results are discussed in a possible unifying view: the OVER-90 population could possess a globally preserved antioxidant ability, though some signs of oxidative damage are present and some structures could be 'sacrificed' in order to keep the redox equilibrium. 相似文献
127.
The Golgi apparatus in plants is organized as a multitude of individual stacks that are motile in the cytoplasm and in close
association with the endoplasmic reticulum (ER) (Boevink et al. in Plant J 15:441–447, 1998). These stacks operate as a sorting centre for cargo molecules, providing modification and redirection to other organelles
as appropriate. In the post-Golgi direction, these include vacuole and plasma membrane, and specialized transport routes to
each are required to prevent mislocalization. Recent evidence in plant cells points to the existence of post-Golgi organelles
that function as intermediate stations for efficient protein traffic, as well as to the influence of small GTPases such as
Rabs and ARFs on post-Golgi trafficking. This review focuses on the latest findings on post-Golgi trafficking routes and on
the involvement of GTPases and their effectors on the trafficking of proteins in the plant secretory pathway.
Sally L. Hanton and Loren A. Matheson have contributed equally to this work. 相似文献
128.
The performance of dental or orthopedic implants is closely dependent on surface properties in terms of topography and chemistry. A phosphated carboxymethylcellulose containing one phosphate group for each disaccharide unit was synthesized and used to functionalize titanium oxide surfaces with the aim to improve osseointegration with the host tissue. The modified surfaces were chemically characterized by means of X-ray photoelectron spectroscopy and Fourier transform infrared spectroscopy. The investigation of the surface topography was performed by atomic force microscopy measurements before and after the polysaccharide coating. In vitro biological tests using osteoblastlike cells demonstrated that functionalized TiO(2) surfaces modulated cell response, in terms of adhesion, proliferation,and morphology. Phosphated carboxymethylcellulose promoted better cell adhesion and significantly enhanced their proliferation. The morphology of cells was polygonal and more spread on this type of modified surface.These findings suggest that the presence of a phosphate polysaccharide coating promotes osteoblast growth on the surface potentially improving biomaterial osseointegration. 相似文献
129.
Francesca Ghirga Federica Aiello Sara Toscano Cinzia Ingallina Mariangela Siler Danilo Cucchi Agnese Po Evelina Miele Davide D'Amico Gianluca Canettieri Enrico De Smaele Elisabetta Ferretti Isabella Screpanti Gloria Uccello Barretta Maurizio Botta Bruno Botta Alberto Gulino Lucia Di Marcotullio 《The EMBO journal》2015,34(2):200-217
130.
Federica Accornero Jop H. van Berlo Robert N. Correll John W. Elrod Michelle A. Sargent Allen York Joseph E. Rabinowitz Andrew Leask Jeffery D. Molkentin 《Molecular and cellular biology》2015,35(12):2154-2164
The matricellular secreted protein connective tissue growth factor (CTGF) is upregulated in response to cardiac injury or with transforming growth factor β (TGF-β) stimulation, where it has been suggested to function as a fibrotic effector. Here we generated transgenic mice with inducible heart-specific CTGF overexpression, mice with heart-specific expression of an activated TGF-β mutant protein, mice with heart-specific deletion of Ctgf, and mice in which Ctgf was also deleted from fibroblasts in the heart. Remarkably, neither gain nor loss of CTGF in the heart affected cardiac pathology and propensity toward early lethality due to TGF-β overactivation in the heart. Also, neither heart-specific Ctgf deletion nor CTGF overexpression altered cardiac remodeling and function with aging or after multiple acute stress stimuli. Cardiac fibrosis was also unchanged by modulation of CTGF levels in the heart with aging, pressure overload, agonist infusion, or TGF-β overexpression. However, CTGF mildly altered the overall cardiac response to TGF-β when pressure overload stimulation was applied. CTGF has been proposed to function as a critical TGF-β effector in underlying tissue remodeling and fibrosis throughout the body, although our results suggest that CTGF is of minimal importance and is an unlikely therapeutic vantage point for the heart. 相似文献