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101.
Flagellum of Legionella pneumophila positively affects the early phase of infection of eukaryotic host cells 总被引:6,自引:0,他引:6 下载免费PDF全文
Legionella pneumophila, the etiologic agent of Legionnaires' disease, contains a single, monopolar flagellum which is composed of one major subunit, the FlaA protein. To evaluate the role of the flagellum in the pathogenesis and ecology of Legionella, the flaA gene of L. pneumophila Corby was mutagenized by introduction of a kanamycin resistance cassette. Immunoblots with antiflagellin-specific polyclonal antiserum, electron microscopy, and motility assays confirmed that the specific flagellar mutant L. pneumophila Corby KH3 was nonflagellated. The redelivery of the intact flaA gene into the chromosome (L. pneumophila Corby CD10) completely restored flagellation and motility. Coculture studies showed that the invasion efficiency of the flaA mutant was moderately reduced in amoebae and severely reduced in HL-60 cells. In contrast, adhesion and the intracellular rate of replication remained unaffected. Taking these results together, we have demonstrated that the flagellum of L. pneumophila positively affects the establishment of infection by facilitating the encounter of the host cell as well as by enhancing the invasion capacity. 相似文献
102.
Markus Pfirrmann Susanne Saussele Andreas Hochhaus Andreas Reiter Ute Berger Dieter K. Hossfeld Christoph Nerl Christof Scheid Karsten Spiekermann Jiri Mayer Andrzej Hellmann Klaus Lechner Christiane Falge Herbert G. Sayer Donald Bunjes Arnold Ganser Dietrich W. Beelen Helen Baldomero Urs Schanz Hermann Heimpel Hans-Jochem Kolb Joerg Hasford Alois Gratwohl Rüdiger Hehlmann 《Journal of cancer research and clinical oncology》2014,140(8):1367-1381
Purpose
In the two consecutive German studies III and IIIA on chronic myeloid leukemia, between 1995 and 2004, 781 patients were randomized to receive either allogeneic hematopoietic stem cell transplantation with a related donor or continued drug treatment. Despite comparable transplantation protocols and most centers participating in both studies, the post-transplant survival probabilities for patients transplanted in first chronic phase were significantly higher in study IIIA (144 patients) than in study III (113 patients). Prior to the decision on a combined analysis of both studies, reasons for this discrepancy had to be investigated.Methods
The Cox proportional hazard cure model was used to identify prognostic factors for post-transplant survival.Results
Donor–recipient matching for human leukocyte antigen, patient age, time between diagnosis and transplantation, and calendar time showed a significant influence on survival and/or the incidence of cure. Added as a further factor, affiliation to study IIIA had no significant impact any longer.Conclusions
Discrepancies in influential prognostic factors explained the different post-transplant survival probabilities between the studies. The significance of calendar time suggests a lack of consistency of transplantation practice over time. Accordingly, the prerequisite for a common assessment of overall survival in the two randomized transplantation arms was not met. Moreover, our analyses provide an independent validation of established prognostic factors and their cutoffs. The statistical approach in investigating and modeling potential prognostic factors for survival sets an example for the examination of studies with unexpected outcome differences in concurrent treatment arms. 相似文献103.
Thiotepa‐based conditioning versus total body irradiation as myeloablative conditioning prior to allogeneic stem cell transplantation for acute lymphoblastic leukemia: A matched‐pair analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation 下载免费PDF全文
Sandra Eder Jonathan Canaani Eric Beohou Myriam Labopin Jaime Sanz William Arcese Reuven Or Juergen Finke Agostino Cortelezzi Dietrich Beelen Jakob Passweg Gerard Socié Gunhan Gurman Mahmoud Aljurf Matthias Stelljes Sebastian Giebel Mohamad Mohty Arnon Nagler 《American journal of hematology》2017,92(10):997-1003
The optimal conditioning regimen to employ before hematopoietic stem cell transplantation in acute lymphoblastic leukemia (ALL) is still undecided, and while cyclophosphamide/total body irradiation (Cy/TBI) is the most commonly used myeloablative regimen, there are concerns regarding long‐term toxicity for patients conditioned with this regimen. Thiotepa‐based conditioning is an emerging radiation‐free regimen with recent publications indicative of comparable clinical outcomes to TBI‐based conditioning. In this analysis of the acute leukemia working party of the EBMT, we performed a retrospective matched‐pair analysis, evaluating the outcome of adult patients with ALL who received thiotepa‐based conditioning (n = 180) with those receiving Cy/TBI conditioning (n = 540). The 2‐year leukemia‐free survival and overall survival (OS) rates of both conditioning regimens were comparable, 33% for thiotepa [95% confidence interval (CI): 26.4‐42.8] versus 39% for Cy/TBI (95% CI: 34.8‐44.5] (P = .33) and 46.5% [95% CI: 38.6‐56.1] versus 48.8% [95% CI: 44.2‐54] (P = .9), respectively. There was no significant difference between the two regimens in the incidence of either acute graft versus host disease (GVHD) or chronic GVHD. Multivariate analysis demonstrated increased relapse incidence for thiotepa conditioning compared to Cy/TBI (HR = 1.78, 95% CI, 1.07‐2.95; P = .03) which did not affect OS. Our results indicate that thiotepa‐based conditioning may not be inferior to Cy/TBI for adult patients with ALL. 相似文献
104.
Neisser Deusch Weigert Kobrak Eckstein Rosenow Tobler Oppenheimer Holzer Finkenrath Dessecker A. W. Fischer Zuntz Peiper Simon Hoffa Eisner-Behrend Seligmann Braun Zinn Dietlen Levinger Kaufmann Reiss Schlesinger Hayward Desseker Eisner H. Hirschfeld Griesbach Dreyfuss Heinrich Davidsohn Freudenberg Jonas V. Jaschke Dietrich Teleky Schönberg 《Journal of molecular medicine (Berlin, Germany)》1922,1(18):910-917
105.
M. Heidenhain W. Heubner Hedbner Oppenheimer Koenigsfeld O. Wiener A. Loewy Sperling Halberstaedter Vaternahm Schübel Versé Mendel Goldstein Weil Deusch Eisner-Behrend W. Zinn Dietlen v. Jaschke v. Schubert Seitz A. W. Fischer Schrader Dietrich Jonas Finkenrath Erich Langer Warsow Weigert G. A. Rost Heubner Kehrer 《Journal of molecular medicine (Berlin, Germany)》1927,6(22):1057-1064
Ohne Zusammenfassung 相似文献
106.
Axhausen Melchior W. Heubner Oppenheimer Dietrich Starkenstein A. W. Fischer Peiper K. Hirschfeld Koch Eisner-Behrend W. Zinn Grassheim Kleinschmidt Weidner Rosenberg W. Israel v. Lichtenberg Hermann Meyer Valentin Herzfeld Deusch Christeller M. Hahn B. Valentin A. Gottstein 《Journal of molecular medicine (Berlin, Germany)》1927,6(16):753-758
Ohne Zusammenfassung 相似文献
107.
108.
In primary and secondary brain diseases, increasing volumes of the three compartments of brain tissue, cerebrospinal fluid, or blood lead to a critical increase in intracranial pressure (ICP). A rising ICP is associated with typical clinical symptoms; however, during analgosedation it can only be detected by invasive ICP monitoring. Other neuromonitoring procedures are not as effective as ICP monitoring; they reflect the ICP changes and their complications by other metabolic and oxygenation parameters. The most relevant parameter for brain perfusion is cerebral perfusion pressure (CPP), which is calculated as the difference between the middle arterial pressure (MAP) and the ICP. A mixed body of evidence exists for the different ICP-reducing treatment measures, such as hyperventilation, hyperosmolar substances, hypothermia, glucocorticosteroids, CSF drainage, and decompressive surgery. 相似文献
109.
Danielle G.E. Lemaire Eberhard Bothe Dietrich Schulte-Frohlinde 《International journal of radiation biology》2013,89(2):319-330
SummaryThe role of dithiothreitol (DTT) and tetranitromethane (TNM) on the yields of radiation-induced strand break formation in polyuridylic acid (poly(U)) was studied in anoxic aqueous solutions at neutral pH by low-angle laser light-scattering. From G (single-strand breaks) as a function of DTT concentration it follows that two different processes lead to OH radical-induced single-strand break (ssb) formation. Only one of the two processes, which accounts for 80 per cent of the ssb formation, is inhibited by DTT, the other one, 20 per cent, is not inhibited. The ‘repair’ process is attributed to H-donation to the C-6-yl radical of the uracil moiety. The C-6-yl radical is produced by OH addition to the C-5 position of the uracil moiety. It follows that the sugar radicals, in contrast to earlier suggestions, do not seem to be repaired by DTT at the low concentrations used. The strand break formation not inhibited by DTT is induced by radicals other than the uracil-6-yl radical, e.g. the uracil-5-yl or the OH radicals reacting with the sugar moiety. The strong reduction of G(ssb) from 2·3 to 0·2 on addition of TNM is also discussed. 相似文献
110.