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131.
Members of the Poxviridae family are particularly adept at avoiding the host immune system, encoding a plethora of immunomodulatory proteins that subvert host defense. With their large genome, poxviruses are also useful for studying the effect of exogenous genes on virus-host interactions and immune responses. The insertion of the Th2 cytokine interleukin-4 (IL-4) into several poxviruses significantly increases the efficiency of the recombinant virus as a pathogen by directly inhibiting the development of Th1 immunity, which is crucial for viral clearance. In an age in which the fear of genetically modified weaponized pathogens exists, the understanding of how to make viruses more pathogenic further blurs the distinction between fundamental academic research and bioweapons development. Here, the extent of immune evasion by IL-4-expressing poxviruses will be explored, as will the consequences of this increased pathogenicity on protective immune responses. 相似文献
132.
Gordon GR Baimoukhametova DV Hewitt SA Rajapaksha WR Fisher TE Bains JS 《Nature neuroscience》2005,8(8):1078-1086
Glial cells actively participate in synaptic transmission. They clear molecules from the synaptic cleft, receive signals from neurons and, in turn, release molecules that can modulate signaling between neuronal elements. Whether glial-derived transmitters can contribute to enduring changes in postsynaptic efficacy, however, remains to be established. In rat hypothalamic paraventricular nucleus, we demonstrate an increase in the amplitude of miniature excitatory postsynaptic currents in response to norepinephrine that requires the release of ATP from glial cells. The increase in quantal efficacy, which likely results from an insertion of AMPA receptors, is secondary to the activation of P2X(7) receptors, an increase in postsynaptic calcium and the activation of phosphatidylinositol 3-kinase. The gliotransmitter ATP, therefore, contributes directly to the regulation of postsynaptic efficacy at glutamatergic synapses in the CNS. 相似文献
133.
134.
Ryuichi Yatani Taizo Shiraishi Kaneyoshi Akazaki Takuji Hayashi Lance K. Heilbrun Grant N. Stemmermann 《Virchows Archiv : an international journal of pathology》1986,409(4):395-405
Summary The histological grades of prostatic carcinoma, as defined by Gleason, were correlated with three methods of morphometry in 254 step-sectioned prostates obtained at autopsy. The variables studied were 1) the number of tumours in each prostate; 2) bilaterality and 3) tumour volume. Each characteristic yielded a statistically significant correlation with histological grade. The strongest correlations were obtained using tumour volume. These autopsy studied help to explain the inconsistent results obtained from morphometric analyses of surgical material, and lend support to the Gleason system as a means of predicting tumour behavior.Supported in part by research contracts PH 64-10, NCI-72-3213, N01-CP-53521; Grant R01-CA-33644; and the Grant-in-Aid for Cancer Research (33) from the Ministry of Health and Welfare 相似文献
135.
136.
137.
C Callaway C Falcon G Grant D H Maurer A D Auerbach Z Rosenwaks M S Pollack 《Human immunology》1986,16(2):200-204
Like fetal fibroblasts and amniotic fluid cells, cultured chorionic villus cells can also be HLA typed with selected typing sera after preincubation with gamma interferon to promote better antigen expression. A modified procedure now in use would also allow any of these cell types to be tested for the presence or absence of all known HLA A,B,C, and DR antigens with standard preplated typing trays. This procedure was used to confirm that an on-going pregnancy had resulted from the successful in vitro fertilization and implantation of an anonymous donor's ovum and could also be of major use in rape or artificial insemination cases when the identity of the possible father(s) is not known. 相似文献
138.
We used the short-circuit current (I(sc)) and patch-clamp techniques to investigate the effects of methoxsalen (MTX) on the electrogenic Cl- secretion of the mouse jejunum. MTX stimulated a sustained increase in Isc that was dose dependent. Bumetanide inhibited MTX-stimulated Isc in a dose-dependent manner consistent with activation of Cl- secretion. MTX failed to stimulate I(sc) following maximal activation of the cAMP pathway by forskolin, but did increase Isc after a submaximal dose of forskolin. Glibenclamide, a blocker of the cystic fibrosis transmembrane conductance regulator (CFTR), reduced the MTX-stimulated increase of Isc by 59 +/- 6%. The cAMP-dependent K+ channel blocker 293B did not alter the MTX-activated I(sc); however, clotrimazole, an intermediate Ca2(+)-activated K+ channel (IK(Ca)) blocker, reduced the MTX-stimulated I(sc). MTX did not alter Na(+)-glucose cotransport across the mouse jejunum. In cell-attached membrane patches, MTX increased the open probability of the basolateral IK(Ca) channel of isolated crypts. These data suggest that the CFTR and IK(Ca) channels participate in the MTX-activated, sustained Cl- secretory response of the mouse jejunum. 相似文献
139.
Thomas L. Patterson Lawrence W. Smith Tom L. Smith Joel Yager Igor Grant 《Journal of behavioral medicine》1992,15(2):113-125
Experiencing adverse life events during childhood may increase vulnerability to physical illnesses and psychological disorders during adulthood. We developed an Early Life Events Questionnaire (ELEQ) with 12 scales and administered it to 92 relatively healthy elderly individuals (29 men and 63 women). A canonical-correlation analysis of the 12 ELEQ scales and physical and psychological symptoms revealed a significant canonical correlation. The results indicate that those who grew up in a family with a harsh climate and whose affiliation needs were not met tended to have more psychological and physical symptoms in old age. Regression analysis revealed that, in men, early life events accounted for 42% of the variance in physical symptoms and 39% in psychological symptoms. No significant relationship, however, was found between ELEQ scales and health outcomes in women. These results suggest that women may be less vulnerable than men to the adverse health consequences of childhood deprivation and other misfortunes.This work was supported by Award SA 325 from the Medical Research Service of the Department of Veterans Affairs. 相似文献
140.
Mutations in VMK1, a mitogen-activated protein kinase gene, affect microsclerotia formation and pathogenicity in Verticillium dahliae 总被引:4,自引:0,他引:4
Rauyaree P Ospina-Giraldo MD Kang S Bhat RG Subbarao KV Grant SJ Dobinson KF 《Current genetics》2005,48(2):109-116
Verticillium dahliae is an important soil-borne fungal pathogen that causes vascular wilt diseases in a large variety of important crop plants.
Due to its persistence in the soil, control of Verticillium wilt relies heavily on soil fumigation. The global ban on methyl bromide, a highly effective soil fumigant, poses an urgent
need to develop alternative control measures against Verticillium wilt; and these might be more forthcoming with a better understanding of the molecular and cellular mechanisms that underpin
the pathogenicity of V. dahliae. In this study, we assessed the role in growth, development, and pathogenicity of VMK1, a gene encoding a mitogen-activated protein (MAP) kinase (hence, Verticillium
MAP Kinase 1). Disruption of VMK1 via Agrobacterium tumefaciens-mediated transformation, in two V. dahliae isolates, one from lettuce and the other from tomato, resulted in severely reduced virulence in diverse host plants, suggesting
that VMK1 is essential for pathogenicity and that the MAP kinase-mediated signaling pathway has a conserved role in fungal pathogenicity.
The vmk1 mutants also exhibited reduced conidiation and microsclerotia formation, suggesting that the gene is important for multiple
cellular processes.
P.R. and R.G.B. equally contributed to the work 相似文献