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31.
Silke Keller Anke Liedek Dalia Shendi Monika Bach Günter E. M. Tovar Petra J. Kluger Alexander Southan 《RSC advances》2020,10(58):35273
Azide-bearing cell-derived extracellular matrices (“clickECMs”) have emerged as a highly exciting new class of biomaterials. They conserve substantial characteristics of the natural extracellular matrix (ECM) and offer simultaneously small abiotic functional groups that enable bioorthogonal bioconjugation reactions. Despite their attractiveness, investigation of their biomolecular composition is very challenging due to the insoluble and highly complex nature of cell-derived matrices (CDMs). Yet, thorough qualitative and quantitative analysis of the overall material composition, organisation, localisation, and distribution of typical ECM-specific biomolecules is essential for consistent advancement of CDMs and the understanding of the prospective functions of the developed biomaterial. In this study, we evaluated frequently used methods for the analysis of complex CDMs. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) and (immune)histochemical staining methods in combination with several microscopic techniques were found to be highly eligible. Commercially available colorimetric protein assays turned out to deliver inaccurate information on CDMs. In contrast, we determined the nitrogen content of CDMs by elementary analysis and converted it into total protein content using conversion factors which were calculated from matching amino acid compositions. The amount of insoluble collagens was assessed based on the hydroxyproline content. The Sircol™ assay was identified as a suitable method to quantify soluble collagens while the Blyscan™ assay was found to be well-suited for the quantification of sulphated glycosaminoglycans (sGAGs). Eventually, we propose a series of suitable methods to reliably characterise the biomolecular composition of fibroblast-derived clickECM.Common characterisation methods for cell-derived extracellular matrices (ECMs) are compared using both unmodified and azide-bearing fibroblast-derived ECM. 相似文献
32.
Sebastian Reuther Silke Szymczak Annette Raabe Kerstin Borgmann Andreas Ziegler Cordula Petersen Ekkehard Dikomey Ulrike Hoeller 《Strahlentherapie und Onkologie》2015,191(1):59-66
Background and purpose
The aim of this study was to determine the impact of functional single nucleotide polymorphism (SNP) pathways involved in the ROS pathway, DNA repair, or TGFB1 signaling on acute or late normal toxicity as well as individual radiosensitivity.Materials and methods
Patients receiving breast-conserving surgery and radiotherapy were examined either for erythema (n?=?83), fibrosis (n?=?123), or individual radiosensitivity (n?=?123). The 17 SNPs analyzed are involved in the ROS pathway (GSTP1, SOD2, NQO1, NOS3, XDH), DNA repair (XRCC1, XRCC3, XRCC6, ERCC2, LIG4, ATM) or TGFB signaling (SKIL, EP300, APC, AXIN1, TGFB1). Associations with biological and clinical endpoints were studied for single SNPs but especially for combinations of SNPs assuming that a SNP is either beneficial or deleterious and needs to be weighted.Results
With one exception, no significant association was seen between a single SNP and the three endpoints studied. No significant associations were also observed when applying a multi-SNP model assuming that each SNP was deleterious. In contrast, significant associations were obtained when SNPs were suggested to be either beneficial or deleterious. These associations increased, when each SNP was weighted individually. Detailed analysis revealed that both erythema and individual radiosensitivity especially depend on SNPs affecting DNA repair and TGFB1 signaling, while SNPs in ROS pathway were of minor importance.Conclusion
Functional pathways of SNPs may be used to form a risk score allowing to predict acute and late radiation-induced toxicity but also to unravel the underlying biological mechanisms.33.
Antibacterial photodynamic treatment of periodontopathogenic bacteria with indocyanine green and near‐infrared laser light enhanced by TroloxTM 下载免费PDF全文
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Kaemmerer H Fratz S Braun SL Koelling K Eicken A Brodherr-Heberlein S Pietrzik K Hess J 《The American journal of cardiology》2004,94(6):825-828
A high percentage of cyanotic adults (37%) with cyanotic congenital cardiac disease (CCD) presented with depleted iron stores (13 of 52) or latent iron deficiency (6 of 52), even in a CCD center in which cyanotic patient phlebotomy is mostly avoided. In many of these patients, hypochromia and microcytosis was frequent, whereas hyperchromia and macrocytosis were relatively common.Furthermore, 50% of patients presented with hyperhomocysteinemia, possibly related to folate or B vitamin deficiencies, which may increase red blood cell size and color, explaining the lack of microcytosis and hypochromia in many cyanotic patients with iron deficiency. 相似文献
37.
Leonard Schuele Hayley Cassidy Erley Lizarazo Katrin Strutzberg-Minder Sabine Schuetze Sandra Loebert Claudia Lambrecht Juergen Harlizius Alex W. Friedrich Silke Peter Hubert G. M. Niesters John W. A. Rossen Natacha Couto 《Viruses》2020,12(12)
Shotgun metagenomic sequencing (SMg) enables the simultaneous detection and characterization of viruses in human, animal and environmental samples. However, lack of sensitivity still poses a challenge and may lead to poor detection and data acquisition for detailed analysis. To improve sensitivity, we assessed a broad scope targeted sequence capture (TSC) panel (ViroCap) in both human and animal samples. Moreover, we adjusted TSC for the Oxford Nanopore MinION and compared the performance to an SMg approach. TSC on the Illumina NextSeq served as the gold standard. Overall, TSC increased the viral read count significantly in challenging human samples, with the highest genome coverage achieved using the TSC on the MinION. TSC also improved the genome coverage and sequencing depth in clinically relevant viruses in the animal samples, such as influenza A virus. However, SMg was shown to be adequate for characterizing a highly diverse animal virome. TSC on the MinION was comparable to the NextSeq and can provide a valuable alternative, offering longer reads, portability and lower initial cost. Developing new viral enrichment approaches to detect and characterize significant human and animal viruses is essential for the One Health Initiative. 相似文献
38.
Anja Brenn Markus Grube Gabriele Jedlitschky Andrea Fischer Barbara Strohmeier Martin Eiden Markus Keller Martin H. Groschup Silke Vogelgesang 《Brain pathology (Zurich, Switzerland)》2014,24(1):18-24
The adenosine triphosphate‐binding cassette transport protein P‐glycoprotein (ABCB1) is involved in the export of beta‐amyloid from the brain into the blood, and there is evidence that age‐associated deficits in cerebral P‐glycoprotein content may be involved in Alzheimer''s disease pathogenesis. P‐glycoprotein function and expression can be pharmacologically induced by a variety of compounds including extracts of Hypericum perforatum (St. John''s Wort). To clarify the effect of St. John''s Wort on the accumulation of beta‐amyloid and P‐glycoprotein expression in the brain, St. John''s Wort extract (final hyperforin concentration 5%) was fed to 30‐day‐old male C57BL/6J‐APP/PS1 +/− mice over a period of 60 or 120 days, respectively. Age‐matched male C57BL/6J‐APP/PS1 +/− mice receiving a St. John''s Wort‐free diet served as controls. Mice receiving St. John''s Wort extract showed (i) significant reductions of parenchymal beta‐amyloid 1–40 and 1–42 accumulation; and (ii) moderate, but statistically significant increases in cerebrovascular P‐glycoprotein expression. Thus, the induction of cerebrovascular P‐glycoprotein may be a novel therapeutic strategy to protect the brain from beta‐amyloid accumulation, and thereby impede the progression of Alzheimer''s disease. 相似文献
39.
Getachew Adam Teketel Yohannes Matthew White Alberto Montaigne Christoph Ulbricht Eckhard Birckner Silke Rathgeber Christian Kästner Harald Hoppe Niyazi Serdar Sariciftci Daniel Ayuk Mbi Egbe 《Macromolecular chemistry and physics.》2014,215(15):1473-1484
Poly(phenylene ethynylene)‐alt‐poly(phenylene vinylene)s (PPE‐PPVs) with various thiophene units (thiophene, bithiophene, and 3,4‐ethylenedioxythiophene) at the X position, with the general backbone design (Ph? C?C? X ? C?C? Ph? CH?CH? Ph? CH?CH? ), bearing identical solubilizing side chains at the phenylene rings of the polymers, are synthesized to study the effect of this structural alteration on the properties such as the photophysics, the electrochemical properties, the charge‐carrier mobility, and the morphology of the materials and its impact on their photovoltaic performance. The polymers are obtained in good yields with reasonable molecular weights and show solubility in ordinary organic solvents required for solution‐processing applications. The polymer with a basic thiophene ring at the X positions shows the highest open‐circuit voltage (VOC of 930 mV) and the polymer with a bithiophene unit at the X position shows the highest short‐circuit current density and charge‐carrier mobility, whereas the polymer with 3,4‐ethylenedioxythiophene shows the lowest photovoltaic performance.
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