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991.
Christian Schiller Johanna E. HuberKalliope N. Diakopoulos Elisabeth H. Weiss 《Human immunology》2013
Carefully orchestrated intercellular communication is an essential prerequisite for an effective immune response. In recent years tunneling nanotubes (TNT) have emerged as a novel mechanism of cell–cell communication. These long membrane protrusions can establish cytoplasmic continuity between distant cells and enable the exchange of cellular components. In the present study we addressed the question whether these structures can facilitate the intercellular transfer of MHC class I molecules. We found a transmembrane HLA-A2-EGFP but not a soluble HLA-G1s-EGFP fusion protein to be effectively transferred between HeLa cells. Inhibition of actin polymerization significantly reduced the HLA-A2 transfer rate, indicating that transfer is dependent on tunneling nanotubes, whose de novo formation requires actin polymerization. Furthermore, overexpression of the nanotube-inducing protein LST1 promoted transfer of HLA-A2. Moreover, LST1 protein expression is enhanced in antigen presenting cells. Our results indicate that tunneling nanotubes can mediate transfer of MHC class I molecules between distant cells. 相似文献
992.
Theresa Förg Christian T. Mayer Abdul Mannan Baru Catharina Arnold‐Schrauf Wendy W. J. Unger Hakan Kalay Yvette van Kooyk Tim Sparwasser 《European journal of immunology》2013,43(10):2543-2553
Vaccination is one of the oldest yet still most effective methods to prevent infectious diseases. However, eradication of intracellular pathogens and treatment of certain diseases like cancer requiring efficient cytotoxic immune responses remain a medical challenge. In mice, a successful approach to induce strong cytotoxic CD8+ T‐cell (CTL) reactions is to target antigens to DCs using specific antibodies against surface receptors in combination with adjuvants. A major drawback for translating this strategy into one for the clinic is the lack of analogous targets in human DCs. DC‐SIGN (DC‐specific‐ICAM3‐grabbing‐nonintegrin/CD209) is a C‐type lectin receptor with potent endocytic capacity and a highly restricted expression on human immature DCs. Therefore, DC‐SIGN represents an ideal candidate for DC targeting. Using transgenic mice that express human DC‐SIGN under the control of the murine CD11c promoter (hSIGN mice), we explored the efficacy of anti‐DC‐SIGN antibodies to target antigens to DCs and induce protective immune responses in vivo. We show that anti‐DC‐SIGN antibodies conjugated to OVA induced strong and persistent antigen‐specific CD4+ and CD8+ T‐cell responses, which efficiently protected from infection with OVA‐expressing Listeria monocytogenes. Thus, we propose DC targeting via DC‐SIGN as a promising strategy for novel vaccination protocols against intracellular pathogens. 相似文献
993.
Martin Schmid Helga Prettenthaler Christian Weger Karl-Heinz Smolle 《Computers in biology and medicine》2013,43(10):1583-1589
In mechanically ventilated patients, Pulse Pressure Variation (PPV) has been shown to be a useful parameter to guide fluid management. We evaluated a real-time automated PPV-algorithm by comparing it to manually calculated PPV-values. In 10 critically ill patients, blood pressure was measured invasively (IBP) and non-invasively (CNAP® Monitor, CNSystems Medizintechnik, Austria). PPV was determined manually and compared to automated PPV values: PPVmanIBP vs. PPVautoIBP was ?0.19±1.65% (mean bias±standard deviation), PPVmanCNAP vs. PPVautoCNAP was ?1.02±2.03% and PPVautoCNAP vs. PPVmanIBP was ?2.10±3.14%, suggesting that the automated CNAP® PPV-algorithm works well on both blood pressure waveforms but needs further clinical evaluation. 相似文献
994.
Thomas H. Grandy Markus Werkle‐Bergner Christian Chicherio Florian Schmiedek Martin Lövdén Ulman Lindenberger 《Psychophysiology》2013,50(6):570-582
The individual alpha frequency (IAF) of the human EEG reflects systemic properties of the brain, is highly heritable, and relates to cognitive functioning. Not much is known about the modifiability of IAF by cognitive interventions. We report analyses of resting EEG from a large‐scale training study in which healthy younger (20–31 years, N = 30) and older (65–80 years, N = 28) adults practiced 12 cognitive tasks for ~100 1‐h sessions. EEG was recorded before and after the cognitive training intervention. In both age groups, IAF (and, in a control analysis, alpha amplitude) did not change, despite large gains in cognitive performance. As within‐session reliability and test‐retest stability were high for both age groups, imprecise measurements cannot account for the findings. In sum, IAF is highly stable in healthy adults up to 80 years, not easily modifiable by cognitive interventions alone, and thus qualifies as a stable neurophysiological trait marker. 相似文献
995.
Harry Sokol Sophie Georgin-Lavialle Danielle Canioni Stéphane Barete Gandhi Damaj Erinn Soucie Julie Bruneau Marie-Olivia Chandesris Felipe Suarez Jean-Marie Launay Achille Aouba Catherine Grandpeix-Guyodo Fanny Lanternier Bernard Grosbois Christian de Gennes Pascal Cathébras Olivier Fain Nadia Hoyeau-Idrissi Patrice Dubreuil Olivier Lortholary Laurent Beaugerie Brigitte Ranque Olivier Hermine 《The Journal of allergy and clinical immunology》2013
996.
Sean P. Saunders Christabelle S.M. Goh Sara J. Brown Colin N.A. Palmer Rebecca M. Porter Christian Cole Linda E. Campbell Marek Gierlinski Geoffrey J. Barton Georg Schneider Allan Balmain Alan R. Prescott Stephan Weidinger Hansjörg Baurecht Michael Kabesch Christian Gieger Young-Ae Lee Roger Tavendale Somnath Mukhopadhyay Stephen W. Turner Vishnu B. Madhok Frank M. Sullivan Caroline Relton John Burn Simon Meggitt Catherine H. Smith Michael A. Allen Jonathan N.W. N. Barker Nick J. Reynolds Heather J. Cordell Alan D. Irvine W.H. Irwin McLean Aileen Sandilands Padraic G. Fallon 《The Journal of allergy and clinical immunology》2013
997.
Christian Massire Daelynn R. Buelow Sean X. Zhang Robert Lovari Heather E. Matthews Donna M. Toleno Raymond R. Ranken Thomas A. Hall David Metzgar Rangarajan Sampath Lawrence B. Blyn David J. Ecker Zhengming Gu Thomas J. Walsh Randall T. Hayden 《Journal of clinical microbiology》2013,51(3):959-966
Invasive fungal infections are a significant cause of morbidity and mortality among immunocompromised patients. Early and accurate identification of these pathogens is central to direct therapy and to improve overall outcome. PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS) was evaluated as a novel means for identification of fungal pathogens. Using a database grounded by 60 ATCC reference strains, a total of 394 clinical fungal isolates (264 molds and 130 yeasts) were analyzed by PCR/ESI-MS; results were compared to phenotypic identification, and discrepant results were sequence confirmed. PCR/ESI-MS identified 81.4% of molds to either the genus or species level, with concordance rates of 89.7% and 87.4%, respectively, to phenotypic identification. Likewise, PCR/ESI-MS was able to identify 98.4% of yeasts to either the genus or species level, agreeing with 100% of phenotypic results at both the genus and species level. PCR/ESI-MS performed best with Aspergillus and Candida isolates, generating species-level identification in 94.4% and 99.2% of isolates, respectively. PCR/ESI-MS is a promising new technology for broad-range detection and identification of medically important fungal pathogens that cause invasive mycoses. 相似文献
998.
Christian Pou Rocío Bellido Maria Casadellà Teresa Puig Bonaventura Clotet Richard Harrigan Roger Paredes 《Journal of clinical microbiology》2013,51(8):2754-2757
Standardization of sequence chromatogram analysis is required for consistent genotypic tropism determination across laboratories. A freely available, fast, and automated chromatogram analysis tool (RECall) provided tropism interpretations equivalent to those of manual sequence editing of 521 V3 loop HIV-1 population sequences, suggesting that RECall can be useful in standardizing genotypic tropism testing across laboratories. 相似文献
999.
Nicole Brazda Christian Voss Veronica Estrada Homaira Lodin Nils Weinrich Klaus Seide Jörg Müller Hans W. Müller 《Biomaterials》2013
Complete transection of the spinal cord leaves a gap of several mm which fills with fibrous scar tissue. Several approaches in rodent models have used tubes, foams, matrices or tissue implants to bridge this gap. Here, we describe a mechanical microconnector system (mMS) to re-adjust the retracted spinal cord stumps. The mMS is a multi-channel system of polymethylmethacrylate (PMMA), designed to fit into the spinal cord tissue gap after transection, with an outlet tubing system to apply negative pressure to the mMS thus sucking the spinal cord stumps into the honeycomb-structured holes. The stumps adhere to the microstructure of the mMS walls and remain in the mMS after removal of the vacuum. We show that the mMS preserves tissue integrity and allows axonal regrowth at 2, 5 and 19 weeks post lesion with no adverse tissue effects like in-bleeding or cyst formation. Preliminary assessment of locomotor function in the open field suggested beneficial effects of the mMS. Additional inner micro-channels enable local substance delivery into the lesion center via an attached osmotic minipump. We suggest that the mMS is a suitable device to adapt and stabilize the injured spinal cord after surgical resection of scar tissue (e.g., for chronic patients) or traumatic injuries with large tissue and bone damages. 相似文献
1000.
Viola Oertel-Knöchel Britta Reinke Richard Feddern Annika Knake Christian Knöchel David Prvulovic Fabian Fußer Tarik Karakaya Deborah Loellgen Christine Freitag Johannes Pantel David E.J. Linden 《Journal of affective disorders》2013