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71.
Mapping of α- and β-globin genes on Antarctic fish chromosomes by fluorescence in-situ hybridization
Eva Pisano Ennio Cocca Federico Mazzei Laura Ghigliotti Guido di Prisco H. William Detrich III Catherine Ozouf-Costaz 《Chromosome research》2003,11(6):633-640
The pathways and mechanisms of genomic change that have led to the peculiar haemoglobinless phenotype of the white-blooded
Antarctic icefishes (16 species in the family Channichthyidae) constitute an important model for understanding the rapid diversification
of the Antarctic notothenioid fish flock. To provide complementary structural information on genomic change at globin-gene
loci in Antarctic fish species, cytogenetic studies and in-situ chromosomal mapping have been undertaken. Using a DNA probe containing one α- and one β-globin gene from the embryonic/juvenile
globin gene cluster of the red-blooded species Notothenia coriiceps, we mapped the cluster on the chromosomes of Antarctic teleosts by fluorescence in-situ hybridization. As anticipated on the basis of its molecular organization, the cluster was located on a single chromosome
pair in all of the red-blooded fish species probed (N. coriiceps, N. angustata, Trematomus hansoni, T. pennellii). In contrast, the α/β-globin probe did not recognize complementary sequences on the chromosomes of the white-blooded species
Chionodraco hamatus and Channichthys rhinoceratus. These results represent the first example of chromosomal mapping of embryonic/juvenile globin genes in teleostean fishes.
Beyond its relevance to the evolutionary history of Antarctic notothenioids, this work contributes to our understanding of
the evolution of the chromosomal loci of globin genes in fishes and other vertebrates.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
72.
Over the last 40 years, the prevalence of smoking in the United States has declined from a peak of approximately 40% in 1965
to 20.9% in 2005. However, the rate of decline has leveled in recent years such that between 2004 and 2005 there was no decline
in smoking prevalence. The prevalence of smoking varies across subpopulations. Among adults, smoking prevalence is currently
highest among those aged 18 to 24 years (24.4%) and those aged 25 to 44 years (24.1%). Women are less likely to smoke than
men; however, the gender gap has narrowed over time. In immigrant populations, smoking prevalence increases with acculturation.
Although smoking prevalence varies widely by state, most states have had a decline over time. Rural populations have a higher
smoking prevalence than urban populations. If further reductions in the prevalence of smoking are to occur, vigilance and
targeted interventions in specific subpopulations will be crucial. 相似文献
73.
74.
Mohand Mesbah Ilka Nemere Petros Papagerakis Jean-Raphael Nefussi Silvana Orestes-Cardoso Catherine Nessmann Ariane Berdal 《Journal of bone and mineral research》2002,17(9):1588-1596
The calciotropic hormone 1,25-dihydroxyvitamin D3 [1,25(OH)2D3] has been established to control skeletal tissue formation and biomineralization via the regulation of gene expression. This action involves the well-characterized nuclear 1,25(OH)2D3 receptor. However, it has been recognized that several cellular responses to 1,25(OH)2D3 may not to be related to the exclusive nuclear receptor. Indeed, this secosteroid is able to generate rapid responses that have been proposed to be mediated by interactions of the ligand, which is a putative cell membrane-associated rapid-response steroid (MARRS) binding protein for 1,25(OH)2D3 [1,25D3-MARRS]. The nongenomic pathway of 1,25(OH)2D3 was studied here in detail by immunolocalization of the 1,25D3-MARRS during the specific context of human prenatal development. Western blotting with proteins extracted from 4 week- to 27-week-old embryos was performed, evidencing a 65-kDa molecular species recognized by antibody Ab 099 generated against synthetic peptides corresponding to the N terminus of the 1,25D3-MARRS from chick intestinal basolateral membranes. Based on this biochemical conservation of protein in the human species, the temporospatial expression patterns were established in the craniofacial skeleton at the same ages. Comparative analysis was performed in teeth and bones from early morphogenesis to terminal cell differentiation and extracellular biomineralization. The data show the potential implication of 1,25D3-MARRS in the heterogeneous cell population including ameloblasts, odontoblasts, osteoblasts, and osteoclasts. The epithelial-mesenchymal cascade related to odontogenesis was coincident with a sequence of up- and down-regulation of immunoreactive 1,25D3-MARRS. Biomineralization was associated with a striking up-regulation in the adjoining secretory cells in all tissues. Finally, osteoclasts appeared also to express the 1,25D3-MARRS during these early phases of bone modeling. Previously obtained data of the nuclear vitamin D receptor (VDR) expression and this study on 1,25D3-MARRS suggest the existence of cross-talk between the genomic and nongenomic pathways during human development. 相似文献
75.
76.
Christian J Streck Paxton V Dickson Catherine Y C Ng Junfang Zhou John T Gray Amit C Nathwani Andrew M Davidoff 《Clinical cancer research》2005,11(16):6020-6029
PURPOSE: Type I IFNs (IFN-alpha/beta) have shown significant antitumor activity in preclinical models but limited efficacy and significant toxicity in clinical trials. We hypothesized that the antitumor activity of type I IFNs could be enhanced by chronic, low-dose systemic delivery and sought to test this in murine neuroblastoma models. EXPERIMENTAL DESIGN: Continuous liver-generated expression of human IFN-beta (hINF-beta) was achieved through a gene therapy-mediated approach using adeno-associated virus vectors encoding hIFN-beta (AAV hINF-beta). Orthotopic localized retroperitoneal and disseminated models of neuroblastoma were established using three different xenografts. Immunohistochemical analysis and ELISA were used to evaluate the antiangiogenic effect of therapy. RESULTS: The development of both localized orthotopic (retroperitoneal) and disseminated neuroblastoma was prevented in all mice expressing hINF-beta. Continued growth of established retroperitoneal tumors, treated with AAV hINF-beta as monotherapy, was significantly restricted, and survival for mice with established, disseminated disease was significantly prolonged following administration of AAV hINF-beta. Analysis of treated tumors revealed a significant antiangiogenic effect. Mean intratumoral vessel density was diminished and expression of the angiogenic factors vascular endothelial growth factor and basic fibroblast growth factor were both decreased. Finally, combination therapy in which AAV hIFN-beta was used together with low-dose cyclophosphamide resulted in regression of both established retroperitoneal and disseminated disease. CONCLUSIONS: AAV-mediated delivery of hIFN-beta when used as monotherapy was able to restrict neuroblastoma growth due in part to inhibition of angiogenesis. When used in combination with conventional chemotherapy, AAV hIFN-beta was able to effect complete tumor regression. 相似文献
77.
G Lallement P Carpentier I Pernot-Marino D Baubichon A Collet G Blanchet 《Neurotoxicology》1991,12(4):655-664
Glutamate (GLU)-receptor subtypes, (quisqualate (QA)-, kainate (KA)-, N- methyl-D-aspartate (NMDA)-receptors) and the phencyclidine sites localized in the ion-channel associated to the NMDA-receptors, were studied by autoradiography in the hippocampus of rats subjected to a convulsive dose of the acetylcholinesterase inhibitor soman (0-, 1,2,2-trimethylpropyl methylphosphonofluoridate). In intoxicated rats, a significant increase in L-[3H]-GLU binding occurred within the first 40 min of seizures in the hippocampal CA3 and CA1 areas. Whereas binding to KA- and NMDA-receptors remained unchanged, L-[3H]-GLU binding to CA3 QA-receptors increased by 31 and 50% respectively after 10 and 40 min of seizures. In CA1, the change in QA-receptors was delayed (+30% after 40 min) and accompanied by an increase in the phencyclidine site binding capacity, reflecting the probable concomitant opening of NMDA ion-channels. These findings confirmed the previously suspected involvement of GLU in the earliest stages of soman-induced seizures, and suggested that, in hippocampus, the primary activation of QA-receptors in the CA3 region could lead to the secondary recruitment of combined non-NMDA (QA) and NMDA mechanisms in CA1. 相似文献
78.
I. Raynaud J. M. Biquard P. Chambard B. Fasciotto J. Samarut J. P. Blanchet V. Krsmanovic 《Archives of virology》1987,93(3-4):213-222
Summary A simultaneous decay of the expression of Im 140 kDa, Im 150 kDa and Im 160 kDa high MW membrane antigens, concomitant with the cell proliferation arrest, was observed during erythropoietin induced differentiation ofts 34 AEV-transformed erythroid cells cultivated at the restrictive temperature. Expression of embryo-immature antigens was maintained during induced differentiation of erythroleukemia cells, but their MW shifted from 50 to 48 kDa, which corresponds to the MW of embryo-immature antigens detected on normal erythroid cells. In the absence of erythropoietin at the restrictive temperature, conditions under which thets 34 AEV-transformed erythroid cells fail to differentiate and maintain their capacity to proliferate, the expression of high MW antigens as well as the expression of embryoimmature antigens remained unaffected. Therefore, it is shown that the expression of specific membrane antigens is modulated under conditions rendering the erythroleukemia cell differentiation process possible.With 3 Figures 相似文献
79.
80.