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排序方式: 共有2357条查询结果,搜索用时 15 毫秒
1.
Richard B Thompson Ewout J van den Bos Bryce H Davis Yoshihisa Morimoto Damian Craig Brad S Sutton Donald D Glower Doris A Taylor 《The Journal of heart and lung transplantation》2005,24(2):205-214
BACKGROUND: Pre-clinical and clinical studies suggest that transplantation of bone marrow-derived stem cells can improve global cardiac function. However, no quantitative assessment of regional systolic contraction and correlation with phenotype has been made. Therefore, we used our model of cryoinfarcted rabbit myocardium for intracardiac transplantation of a mixed population of bone marrow-derived cells and assessed both regional function and myogenic conversion of the cells. METHODS: Nineteen New Zealand white rabbits underwent cryoinjury of the left ventricle. Autologous bone marrow (BM) cells were expanded in vitro. After 2 weeks, either 1 x 10(8) mixed BM-derived progenitor cells (BM group, n = 11) or vehicle (control group, n = 8) were injected into the cryoinjured region. Regional systolic function was measured using micromanometry and sonomicrometry before and 4 weeks after cell injection; cell phenotype was evaluated histologically. RESULTS: All animals in the BM group significantly improved both systolic shortening (0.11 +/- 0.7 vs -0.05 +/- 0.05 mm in the control group, p < 0.05) and regional stroke work when compared with control (9.6 +/- 2.4 vs -1.2 +/- 1.2 mm . mm Hg, p < 0.003). In addition, the BM group had improved global diastolic function, as measured by minimum dP/dt and end-diastolic pressure. On histologic assessment, BM cells differentiated toward a myogenic phenotype. CONCLUSIONS: Transplanting a mixed population of marrow-derived cells that can adopt a myogenic phenotype improves regional contractility and diastolic relaxation after myocardial infarction. 相似文献
2.
Dissociated cell culture of rat cerebral cortical neurons in serum-free, conditioned media: GABA-immunopositive neurons. 总被引:1,自引:0,他引:1
The gamma-aminobutyric acid (GABA)ergic properties of embryonic (E15d) rat cortical neurons were studied in dissociated serum-free culture by immunohistochemical methods. GABA-like immunoreactivity was found in a subpopulation of neurons from the first day onwards. The number of GABA-positive neurons reached mature values (10.5-12.6%) within the first week, while their morphological differentiation was not found to be fully completed until the 11th day of culture and was characterized by several discrete developmental stages. First, GABA-positive neurons gained their mature complement of neurites at 3 days in vitro (DIV). Three days later somal maturation became evident, followed at least by the maturation of the neuritic arbor. Double-labelling studies revealed the coexpression of GABA and tyrosine hydroxylase within the same cells. The similarities of relative number, morphology, time course of development and biochemistry of cultured GABAergic neurons compared with those in situ suggest that the applied culture system is a useful model to investigate several aspects of GABAergic neurotransmission at the cellular level. 相似文献
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Thomas Patrick S. Jr; Fraley Gregory S.; Damian Vincent; Woodke Lillie B.; Zapata Francisco; Sopher Bryce L.; Plymate Stephen R.; La Spada Albert R. 《Human molecular genetics》2006,15(19):2972
Human Molecular 相似文献
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Xiao FX Yotova V Zietkiewicz E Lovell A Gehl D Bourgeois S Moreau C Spanaki C Plaitakis A Moisan JP Labuda D 《European journal of human genetics : EJHG》2004,12(4):301-311
Within Europe, classical genetic markers, nuclear autosomal and Y-chromosome DNA polymorphisms display an east-west frequency gradient. This has been taken as evidence for the westward migration of Neolithic farmers from the Middle East. In contrast, most studies of mtDNA variation in Europe and the Middle East have not revealed clinal distributions. Here we report an analysis of dys44 haplotypes, consisting of 35 polymorphisms on an 8 kb segment of the dystrophin gene on Xp21, in a sample of 1203 Eurasian chromosomes. Our results do not show a significant genetic structure in Europe, though when Middle Eastern samples are included a very low but significant genetic structure, rooted in Middle Eastern heterogeneity, is observed. This structure was not correlated to either geography or language, indicating that neither of these factors are a barrier to gene flow within Europe and/or the Middle East. Spatial autocorrelation analysis did not show clinal variation from the Middle East to Europe, though an underlying and ancient east-west cline across the Eurasian continent was detected. Clines provide a strong signal of ancient major population migration(s), and we suggest that the observed cline likely resulted from an ancient, bifurcating migration out of Africa that influenced the colonizing of Europe, Asia and the Americas. Our study reveals that, in addition to settlements from the Near East, Europe has been influenced by other major population movements, such as expansion(s) from Asia, as well as by recent gene flow from within Europe and the Middle East. 相似文献
8.
McGlinchey PG Spence MS Patterson CC Allen AR Murphy G Fogarty D Evans A McKeown PP 《Disease markers》2004,20(6):289-294
Matrix metalloproteinase-3 (MMP-3) has been proposed as an important mediator of the atherosclerotic process. The possible role of the functional -1612 5A/6A polymorphism of the MMP-3 gene in the susceptibility to ischaemic heart disease (IHD) was investigated in a well-defined Irish population using two recently described family based tests of association. One thousand and twelve individuals from 386 families with at least one member prematurely affected with IHD were genotyped. Using the combined transmission disequilibrium test (TDT)/sib-TDT and the pedigree disequilibrium test (PDT), no association between the MMP-3 -1612 5A/6A polymorphism and IHD was found. Our data demonstrate that, in an Irish population, the MMP-3 -1612 5A/6A polymorphism is not associated with IHD. 相似文献
9.
Thurman JM Kraus DM Girardi G Hourcade D Kang HJ Royer PA Mitchell LM Giclas PC Salmon J Gilkeson G Holers VM 《Molecular immunology》2005,42(1):87-97
Studies in gene-targeted mice have demonstrated that factor B of the alternative complement pathway plays an important role in several disease models, but an exogenous inhibitor of factor B has not previously been available. We have developed an inhibitory monoclonal antibody directed against a critical epitope on mouse factor B and have tested it in a model of antiphospholipid (aPL) antibody (Ab)-induced fetal loss. Gene-targeted factor B-deficient mice (fB-/-) were injected with a fusion protein comprised of the second and third short consensus repeat (SCR) domains of mouse factor B linked to a mouse IgG1 Fc domain. Hybridomas were made from splenocytes of the immunized mouse. One mAb, designated 1379, produced an IgG1 antibody that inhibited alternative pathway activation in vitro and in vivo by preventing formation of the C3bBb complex. Strikingly, this mAb inhibited alternative pathway activation in serum from mice, rats, humans, monkeys, pigs and horses. Fab fragments made from this mAb also inhibited alternative pathway activation. Epitope mapping demonstrated that this antibody binds to factor B within the third SCR domain. When mAb 1379 was administered to mice that also received human IgG containing antiphospholipid antibodies, it provided significant protection from antiphospholipid antibody-induced complement activation and fetal loss. Thus, this mAb to factor B has broad species reactivity and effectively inhibits alternative pathway activation. The mAb protects mice in an in vivo model of antiphospholipid antibody syndrome, demonstrating the therapeutic potential for the inhibition of factor B in this disease. 相似文献
10.
Florin Ciuprina Denis Mihaela Panaitescu Laura Enache Celina Maria Damian Ramona Marina Grigorescu Augusta Raluca Gabor Cristian Andi Nicolae Cristina Lavinia Nistor Roxana Trusca 《Materials》2022,15(21)
The structure–property relationship of dielectric elastomers, as well as the methods of improving the control of this relationship, has been widely studied over the last few years, including in some of our previous works. In this paper, we study the control, improvement, and correlation, for a significant range of temperatures, of the mechanical and dielectric properties of polystyrene-b-(ethylene-co-butylene)-b-styrene (SEBS) and maleic-anhydride-grafted SEBS (SEBS-MA) by using graphite (G) as filler in various concentrations. The aim is to analyze the suitability of these composites for converting electrical energy into mechanical energy or vice versa. The dielectric spectroscopy analysis performed in the frequency range of 10 to 1 MHz and at temperatures between 27 and 77 °C emphasized an exponential increase in real permittivity with G concentration, a low level of dielectric losses (≈10−3), as well as the stability of dielectric losses with temperature for high G content. These results correlate well with the increase in mechanical stiffness with an increase in G content for both SEBS/G and SEBS-MA/G composites. The activation energies for the dielectric relaxation processes detected in SEBS/G and SEBS-MA/G composites were also determined and discussed in connection with the mechanical, thermal, and structural properties resulting from thermogravimetric analysis, differential scanning calorimetry, Fourier-transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses. 相似文献