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981.
982.
Protein kinases catalyze the phosphorylation of serine/threonine or tyrosine residues, which may directly alter a protein’s functional properties. Kinases can also regulate protein functions indirectly, for example, by controlling the composition and/or subcellular localization of members of multiprotein complexes that associate with the regulated protein. In this issue of the JCI, two separate studies by Weinman et al. and Yang et al. examine the second of these two modes of kinase-mediated regulation and demonstrate the effects of kinases on two Na+-driven renal cotransporters (see the related articles beginning on pages 3403 and 3412). Their results reveal important implications for phosphate and salt homeostasis, respectively. 相似文献
983.
We report the conservative treatment of a spontaneous spinal epidural haematoma attending with acute extensive neurological deficits, which resolved spontaneously. Spontaneous remission of spontaneous spinal epidural haematoma with severe neurological deficit is rare in the literature. An 80 year old man was admitted to our hospital presenting sciatica followed by rapid development of paraparesis and cauda equina syndrome, which represents a neurosurgical emergency. Magnetic resonance imaging revealed a multilevel epidural haematoma from L1 to L5. During the initial diagnostic procedure the symptoms started to decline unexpectedly, so the surgical intervention could be withdrawn. Twenty four hours after admission the patient was almost free of symptoms, mobile, and continent. Awareness and high index of suspicion, and a willingness to seek the prompt help of the imaging department, are crucial to successful management before the opportunity to treat is lost. 相似文献
984.
Hahn G Beer M Frerichs I Dudykevych T Schröder T Hellige G 《Physiological measurement》2000,21(1):53-60
The test concept as well as the design of a simple resistor phantom suitable for the evaluation of the properties of electrical impedance tomographic (EIT) systems is presented. Input and transfer impedance of the phantom are matched with those of the human thorax. Amplitude of the local impedance variations similar to in vivo conditions (ventilation) can be intentionally set to perform measurements on different states. The theoretical potential differences between the electrodes are calculated. The evaluation procedure is performed in terms of the local amplitude of the relative impedance change as well as the local distribution of noise. The whole procedure can be applied either to compare quantitatively the performance of different EIT data acquisition systems or to determine the amount of measurement disturbance caused by the external electrical environment in clinical settings. 相似文献
985.
Akt1/protein kinase Balpha is critical for ischemic and VEGF-mediated angiogenesis 总被引:1,自引:0,他引:1
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Ackah E Yu J Zoellner S Iwakiri Y Skurk C Shibata R Ouchi N Easton RM Galasso G Birnbaum MJ Walsh K Sessa WC 《The Journal of clinical investigation》2005,115(8):2119-2127
Akt, or protein kinase B, is a multifunctional serine-threonine protein kinase implicated in a diverse range of cellular functions including cell metabolism, survival, migration, and gene expression. However, the in vivo roles and effectors of individual Akt isoforms in signaling are not explicitly clear. Here we show that the genetic loss of Akt1, but not Akt2, in mice results in defective ischemia and VEGF-induced angiogenesis as well as severe peripheral vascular disease. Akt1 knockout (Akt1-/-) mice also have reduced endothelial progenitor cell (EPC) mobilization in response to ischemia, and reintroduction of WT EPCs, but not EPCs isolated from Akt1-/- mice, into WT mice improves limb blood flow after ischemia. Mechanistically, the loss of Akt1 reduces the basal phosphorylation of several Akt substrates, the migration of fibroblasts and ECs, and NO release. Reconstitution of Akt1-/- ECs with Akt1 rescues the defects in substrate phosphorylation, cell migration, and NO release. Thus, the Akt1 isoform exerts an essential role in blood flow control, cellular migration, and NO synthesis during postnatal angiogenesis. 相似文献
986.
987.
Chlamydia trachomatis infections are among the most common sexually transmitted diseases and of great epidemiological importance world-wide. Identification of this pathogen can be difficult, and it is highly desirable to have a rapid and accurate nucleic acid based detection method. Several commercial PCR test systems are available (e.g. CobasAmplicor, Roche, Mannheim, Germany) but they require post-amplification detection by hybridization resulting in extended work-up time and possible cross-contamination. The objective of our study was to develop a routine diagnostic method for the sensitive, specific and rapid detection of C. trachomatis. The obvious choice is real-time PCR without any post-amplification procedures. The dye SYBR Green I (intercalating in dsDNA) provides a simple and fast real-time PCR in the LightCycler. Specific primer design combined with melting curve analysis allows a reliable and sensitive identification of C. trachomatis. In addition, a new commercial real-time PCR system (RealArt C. trachomatis LC PCR Reagents, artus, Hamburg, Germany) was evaluated, that combines sequence-specific primers and fluorescence-labelled (FRET) 5'-nuclease probes. An internal control integrated in this system detects false negative results and erroneous PCR conditions. All results were compared with the corresponding data from an analysis using the CobasAmplicor system (Roche). (Clin 相似文献
988.
Preemptive treatment of early donor‐specific antibodies with IgA‐ and IgM‐enriched intravenous human immunoglobulins in lung transplantation
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![点击此处可从《American journal of transplantation》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Fabio Ius Murielle Verboom Wiebke Sommer Reza Poyanmehr Ann‐Kathrin Knoefel Jawad Salman Christian Kuehn Murat Avsar Thierry Siemeni Caroline Erdfelder Michael Hallensleben Dietmar Boethig Nicolaus Schwerk Carsten Mueller Tobias Welte Christine Falk Axel Haverich Igor Tudorache Gregor Warnecke 《American journal of transplantation》2018,18(9):2295-2304
This retrospective study presents our 4‐year experience of preemptive treatment of early anti‐HLA donor specific antibodies with IgA‐ and IgM‐enriched immunoglobulins. We compared outcomes between patients with antibodies and treatment (case patients) and patients without antibodies (control patients). Records of patients transplanted at our institution between March 2013 and November 2017 were reviewed. The treatment protocol included one single 2 g/kg immunoglobulin infusion followed by successive 0.5 g/kg infusions for a maximum of 6 months, usually combined with a single dose of anti‐CD20 antibody and, in case of clinical rejection or positive crossmatch, with plasmapheresis or immunoabsorption. Among the 598 transplanted patients, 128 (21%) patients formed the case group and 452 (76%) the control group. In 116 (91%) patients who completed treatment, 106 (91%) showed no antibodies at treatment end. Fourteen (13%) patients showed antibody recurrence thereafter. In case versus control patients and at 4‐year follow‐up, respectively, graft survival (%) was 79 versus 81 (P = .59), freedom (%) from biopsy‐confirmed rejection 57 versus 53 (P = .34), and from chronic lung allograft dysfunction 82 versus 78 (P = .83). After lung transplantation, patients with early donor‐specific antibodies and treated with IgA‐ and IgM‐enriched immunoglobulins had 4‐year graft survival similar to patients without antibodies and showed high antibody clearance. 相似文献
989.
Schrör K 《Wiener klinische Wochenschrift》1999,111(3):90-97
Acute occlusion of a large coronary artery by a platelet thrombus is a life-threatening event. Intravasal thrombus generation in most cases is caused by a disturbed interaction between platelets and the vessel wall, with accompanying platelet hyperreactivity, local adhesion to the vessel wall, activation and aggregate formation after binding of soluble fibrinogen to the activated GP IIb/IIIa-receptor. Conventional antiplatelet agents, such as aspirin or ticlopidine/clopidogrel, inhibit uncontrolled local agonist-induced signal transduction within the platelet by interfering with the thromboxane A2 and ADP pathway, respectively. This results in an activation of the platelet GP IIb/IIIa-receptor and, finally, in a reduced capacity of fibrinogen binding. Antiintegrins inhibit cell-cell and cell-matrix interactions. Antagonists of the platelet integrin alpha IIB/beta 3 (GP IIb/IIIa) (eg. Abciximab, Eptifibatide, Tirofiban) inhibit platelet adhesion and aggregation via their RGD (KGD) binding sequence, resulting in reduced fibrinogen binding. The significance of inhibition of other RGD-containing adhesion molecules (von Willebrand Factor, Vitronectin) with respect to the clinical efficacy of these compounds is stil under debate. GP IIb/IIIa-antagonists are the most effective inhibitors of platelet function and in high doses, may cause complete inhibition of platelet aggregation and maximum prolongation of bleeding time. The clinical efficacy of GP IIb/IIIa-antagonists for acute percutaneous coronary interventions and in the management of the acute coronary syndrome is established. Whether Abciximab and low-molecular weight intravenous compunds (Eptifibatide, Tirofiban, Lamifiban) are equipotent, remains to be demonstrated by controlled comparative studies. Orally active low-molecular-weight compounds (Sibrafiban, Xemilofiban and others) are currently undergoing clinical trials. Whether these substances are superior to oral aspirin and/or clopidogrel in long-term prevention of acute arterial vessel occlusions remains to be determined. 相似文献
990.
Englert C Fierlbeck J von Glasser SS Nerlich M Hammer J 《Clinical biomechanics (Bristol, Avon)》2007,22(7):849-855
BACKGROUND: Sutures for adaptation of articular cartilage are used in arthritis therapy techniques. However, little is known about the mechanical functionality of these sutures. The objective of the present work was to compare the mechanical properties of articular cartilage bonds either generated by suture, or, alternatively, by chemical cross-linking of the opposing surfaces or in vitro integrative repair of cartilage blocks. METHODS: Bonding was achieved by suture in varying numbers, positions and orientations, by surface cross-linking using carbodiimide in combination with pepsin or guanidine (immediate bonding), or by cultivation for 14 days, either with or without testosterone. The mechanical properties of the cartilage bonds were measured under tensile loading. FINDINGS: Suture led to the highest maximal load at failure and by far to the highest strain and lowest stiffness of the bonded samples. Immediate bonding by chemical cross-linking in combination with pepsin led to a low force at failure, but the highest stiffness, as compared to all other groups. Cultivation in the presence of testosterone led to a higher force at failure and a higher strain than chemical cross-linking. INTERPRETATION: Suture technique for bonding of cartilage surfaces leads to a very elastic adaptation which allows synovial fluid flow in between the interface of cartilage wounds. Long-term bonding of cartilage wounds would be counteracted by a fluid flow through the interface during motion of the joint. Immediate bonding of cartilage wounds by chemical cross-linking reagents might be a useful alternative tool. Even more promising, with regard to the mechanical properties, appears to be integrative repair of cartilage blocks stimulated by testosterone. 相似文献