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991.
Lipopolysaccharides from different bacterial sources elicit disparate cytokine responses in whole blood assays 总被引:2,自引:0,他引:2
Mathiak G Kabir K Grass G Keller H Steinringer E Minor T Rangger C Neville LF 《International journal of molecular medicine》2003,11(1):41-44
The stimulatory effects of different purified lipopolysaccharide (LPS) preparations from E. coli, S. typhosa, P. aeruginosa, and K. pneumoniae on cytokine and chemokine production were measured in whole blood assays by ELISA. Incubation of 0.5 ml whole blood with 10 ng/ml E. coli and S. typhosa resulted in a time-dependent production of TNF-alpha, IL-1beta, IFN-gamma, IL-10 and MCP-1. K. pneumoniae, however, showed preferential effects on IL-1beta, IL-10 and MCP-1 production with less potent effects on TNF-alpha and IFN-gamma. LPS derived from P. aeruginosa showed a similar potency to other LPS preparations on MCP-1 production, yet completely failed to elicit the production of other cytokines. To further investigate potencies of the different LPS preparations, mediator production was determined following stimulation with agonist concentrations of 0.1 ng and 1000 ng per ml over a 24 h time period. Dose-response curves were obtained with LPS derived from E. coli, S. typhosa and K. pneumoniae on all mediators apart from IL-1beta and MCP-1. Most strikingly though, was the ability of LPS derived from P. aeruginosa to selectively elicit a significant dose-response effect on MCP-1 production, despite its very weak stimulatory effects on all other cytokines. These data imply that the bacterial origin of different LPS preparations can exhibit disparate effects on inflammatory mediator production. Furthermore, the potent, selective dose-response effect of P. aeruginosa LPS on MCP-1 production could help to explain the preponderance of a relentless inflammatory cellular infiltrate in diseases such as cystic fibrosis (CF). 相似文献
992.
Hendrik J. Kevelam Klaas P. de Jong Herman C. Meinders Gerrit Challa 《Macromolecular chemistry and physics.》1975,176(5):1369-1381
A study was made of the influence of the concentrations of catalyst, monomer, water, ligand, and oxygen on the rate of oxidative polymerization of 1,8-nonadiyne ( 1 ) at 26°C in the presence of homogeneous catalysts derived from cuprous chloride (copper(I) chloride) and tertiary amines. In the initial stages the reaction is nearly first order in [Cu2Cl2] up to the solubility limit of the active catalyst, and second to first order in [ 1 ] for low to medium monomer concentrations. The reaction rate decreases with increasing water content and is enhanced by increasing ligand concentration and increasing basicity of the ligand: triethylamine (TEA) > N,N,N',N'-tetramethylethylenediamine (TMED) > pyridine. On the basis of these kinetic results and a study of the catalyst structure a reaction scheme is proposed. In this scheme the formation of water occurs in reversible reaction steps from acetylenic endgroups and a dimeric copper(II) complex [TMED. Cu(OH)] · 2Cl?, followed by intramolecular oxidative coupling of two complexed acetylide ions. 相似文献
993.
Leoné Malan Aletta Elisabeth Schutte Nicolaas Theodor Malan Maria Philipina Wissing Hester Hendrina Vorster Hendrik Stefanus Steyn Johannes Marthinus van Rooyen Hugo Willem Huisman 《International journal of psychophysiology》2006,61(2):158-166
The purpose of this study was to compare active and passive coping strategies of Africans with perception of own health and cardiovascular data. The subjects included 236 apparently healthy Africans (men=109; women=127). The COPE questionnaire was adapted, translated and validated for Africans. Scores on reliable sub-scales were used to classify men and women into more active coping (AC) and more passive coping (PC) subgroups. The General Health Questionnaire measured subjective perception of health. Blood pressure was recorded before and during application of the handgrip test, using the Finapres, a continuous non-invasive blood pressure monitor. Plasma renin activity (PRA) values, measured with radio immuno assay, were compared to blood pressure variables. Analyses of co-variance, adjusted for resting values and age, indicated that PC men responded with a larger increase in total peripheral resistance (TPR) (p=0.006), larger decrease in stroke volume (p=0.07), smaller increase in cardiac output (p=0.09) and larger increases in PRA resting (p=0.04) and reactivity (p< or =0.05) values. PC subjects reported a more negative perception of health than AC subjects. Young PC women presented greater hypertension prevalence rates (p< or =0.01) than AC women. In conclusion, all AC and PC subjects reacted with increased vascular reactivity on the handgrip test. PC men presented enhanced vascular reactivity, PRA and perception of poorer health values. 相似文献
994.
995.
Diana Le Duc Julia Hentschel Sonja Neuser Mathias Stiller Carolin Meier Elisabeth Jger Rami Abou Jamra Konrad Platzer Astrid Monecke Mirjana Ziemer Aleksander Markovic Hendrik Blker Johannes R. Lemke 《European journal of human genetics : EJHG》2021,29(3):489
Pathogenic variants in TP53 have been classically thought to cause Li-Fraumeni syndrome (LFS), a cancer predisposition with high risks for various childhood- and adult-onset malignancies. However, increased genetic testing has lately revealed, that pathogenic variant carriers exhibit a broader range of phenotypes and that penetrance may be dependent both on variant type and modifiers. Using next generation sequencing and short tandem repeat analysis, we identified germline pathogenic variants in TP53 and RAD51C located in cis on chromosome 17 in a 43-year-old male, who has developed a rare sebaceous gland carcinoma (SGC) but so far no tumors of the LFS spectrum. This course mirrors a Trp53-Rad51c-double-mutant cis mouse-model, which similarly develops SGC, while the characteristic Trp53-associated tumor spectrum occurs with significantly lower frequency. Therefore, we propose that co-occurent pathogenic variants in RAD51C and TP53 may predispose to SGC, reminiscent of Muir-Torre syndrome. Further, this report supports the diversity of clinical presentations associated with germline TP53 alterations, and thus, the proposed expansion of LFS to heritable TP53-related cancer syndrome.Subject terms: Genetics research, Cancer genetics 相似文献
996.
997.
Rational design of new CpG oligonucleotides that combine B cell activation with high IFN-alpha induction in plasmacytoid dendritic cells 总被引:15,自引:0,他引:15
Hartmann G Battiany J Poeck H Wagner M Kerkmann M Lubenow N Rothenfusser S Endres S 《European journal of immunology》2003,33(6):1633-1641
Two different types of CpG motif-containing oligonucleotides (CpG ODN) have been described: CpG-A with high induction of IFN-alpha in plasmacytoid dendritic cells; and CpG-B with little induction of IFN-alpha, but potent activation of B cells. In this study, we demonstrate that CpG-A fail to activate B cells unless plasmacytoid dendritic cells are present. We identified a new set of CpG ODN sequences which induces high levels of IFN-alpha in plasmacytoid dendritic cells but remains capable of directly activating B cells. These new CpG ODN (termed CpG-C) are more potent stimulants of B cells than CpG-B due to their ability of directly and indirectly (via plasmacytoid dendritic cells) activating B cells. The sequence of CpG-C combines structural elements of both CpG-A and CpG-B. The most potent sequence, M362, contains a 5'-end 'TCGTCG-motif' and a 'GTCGTT-motif', both of which are present in CpG-B (ODN 2006); a palindromic sequence characteristic for CpG-A (ODN 2216); but no poly G motif required for CpG-A. In conclusion, we defined the first CpG-containing sequences that potently activate both TLR9-expressing immune cell subsets in humans, the plasmacytoid dendritic cell and the B cell. CpG-C may allow for improved therapeutic immuno-modulation in vivo. 相似文献
998.
Aulmann S Schnabel PA Helmchen B Dienemann H Drings P Otto HF Sinn HP 《Virchows Archiv : an international journal of pathology》2005,446(3):305-309
Primary acantholytic squamous cell carcinoma (ASCC) of the breast is a rare and aggressive variant of invasive breast cancer. Here we report two new cases of ASCC and their immunohistochemical and cytogenetic characterization. One case was associated with systemic metastases and death and the other with local failure prior to loss of follow-up. Using comparative genomic hybridization (CGH), both tumors showed a high overall number of chromosomal imbalances with a similar pattern of gains and losses. Genetic aberrations common to both tumors included losses at 3p11-p25, 5q21-q31, 8p, 9, 13p13-q21, 16q12-q21, and 17p and gains at 1q31-qter, 7p, 18q12-qter, 19q, and 20. Immunohistochemically, the tumors were characterized by high proliferative activity, an uncommon cytokeratin expression profile, reduced E-cadherin staining, and overexpression of p53 and epithelial growth factor receptor (EGFR). The results of our analyses suggest that genetic alterations observed in ASCC of the breast include imbalances commonly observed in both mammary adenocarcinoma and squamous cell carcinoma of other locations. Furthermore, the overexpressed EGFR could be a possible therapeutic target for individual cases of this aggressive tumor type. 相似文献
999.
Hendrik Van Der Loos 《Neuroscience letters》1976,2(1):1-6
In the mouse, in the medial part of the ventrobasal complex of the thalamus (VBm), an array of rod-shaped domains, poor in perikarya and with a diameter of about 70 μm, is embedded in a lattice of high cell packing-density. Each domain forms the core of a ‘barreloid’. The arrangement of barreloids is topologically equivalent to that of the large barrels in the cortical somatosensory area (SI). 相似文献
1000.
Hendrik Seeliger Markus Guba Gudrun E Koehl Axel Doenecke Markus Steinbauer Christiane J Bruns Christine Wagner Erika Frank Karl-Walter Jauch Edward K Geissler 《Clinical cancer research》2004,10(5):1843-1852
PURPOSE: Colorectal neoplasms remain a leading cause of cancer-related deaths. A recognized weakness of conventional 5-fluorouracil (5-FU) therapy relates to expression of the intracellular enzyme, thymidine phosphorylase (TP). Although TP promotes 5-FU cytotoxicity, TP-derived 2-deoxy-D-ribose (dRib) counterproductively stimulates tumor angiogenesis. Here, the newly discovered antiangiogenic drug rapamycin was combined with 5-FU to counteract the potential escape mechanism of dRib-induced angiogenesis. EXPERIMENTAL DESIGN: Orthotopic tumor growth was assessed in rapamycin and 5-FU-treated BALB/c mice with TP-expressing CT-26 colon adenocarcinoma cells. To examine liver metastasis, green-fluorescent protein-transfected CT-26 cells were visualized by fluorescence microscopy after intraportal injection. Cell counting and Ki67 staining were used to determine in vitro and in vivo cell expansion, respectively. In vitro angiogenic effects of dRib were assessed with endothelial cell migration and aortic ring assays. Western blotting detected dRib effects on p70/S6 kinase activation. RESULTS: Rapamycin treatment of mice bearing orthotopic tumors inhibited tumor growth more than did 5-FU, and mice treated with both drugs typically developed no tumors. In the liver metastasis assay, combination therapy blocked metastatic expansion of solitary tumor cells. Interestingly, complex drug activities were suggested by tumor-cell proliferation being more sensitive to 5-FU than to rapamycin in vitro, but more sensitive to rapamycin in vivo. With regard to angiogenesis, dRib-induced endothelial cell migration and aortic ring formation were completely abrogated by rapamycin, correlating with blockage of dRib-induced p70/S6 kinase activation in endothelial cells. CONCLUSIONS: Inhibition of dRib-induced angiogenesis with rapamycin counteracts a potential TP-based escape mechanism for colorectal cancer under 5-FU therapy, introducing a novel, clinically feasible, combination treatment option for this common neoplasm. 相似文献