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21.
Liu X Beaty TH Deindl P Huang SK Lau S Sommerfeld C Fallin MD Kao WH Wahn U Nickel R 《The Journal of allergy and clinical immunology》2003,112(2):382-388
BACKGROUND: Increased total serum IgE levels are a common characteristic of atopic disorders. Six potentially functional variants, including C-590T in the IL4 gene, C-1055T and Arg130Gln in the IL13 gene, and Ile50Val, Ser478Pro, and Gln551Arg in the IL4RA gene, have been evaluated for their involvement in the control of total serum IgE levels and related atopic disorders, but the results of these studies have been inconsistent. OBJECTIVE: We examined whether these 6 variants had genotypic effects on total serum IgE levels in 823 unrelated German children from a large infant cohort, the German Multicenter Atopy Study. METHODS: Marginal effect models were used for the analyses of the repeated IgE measurements. Weighted linear regression and family-based tests of association were performed to minimize the possibility of spurious effects caused by selection bias or confounding on the basis of ethnic background. RESULTS: There are significant associations between increased total serum IgE levels and 2 variants in the IL13 gene (P <.005 and.0002 for Arg130Gln and C-1055T, respectively). These genetic effects are unlikely to be due to solely linkage disequilibrium between 2 polymorphisms, population stratification, or nonrepresentative samples. In addition, exposure to maternal smoking appears to modify the above effects on total serum IgE levels. However, no statistical association was observed between this quantitative phenotype and the other 4 variants examined. CONCLUSION: These findings suggest that variants C-1055T and Arg130Gln of the IL13 gene might play an important role on total serum IgE production in this study population. 相似文献
22.
Ingeborg S. Aaberge Philipp Oster Oddveig S. Helland Anne-Cathrine Kristoffersen Ellen Ypma E. Arne H?iby Berit Feiring Hanne N?kleby 《Clinical and Vaccine Immunology : CVI》2005,12(5):599-605
MenBvac and Menjugate are safe and efficacious vaccines. The purpose of this study was to evaluate safety and immunogenicity of the combination (MenB/C) of the lyophilized active components of the conjugated group C vaccine Menjugate when reconstituted with the full liquid group B outer membrane vesicle vaccine MenBvac compared to MenBvac and Menjugate given separately. At 6-week intervals, healthy adults were given one dose of MenB/C followed by two doses of MenBvac (MenB/C group), three doses of MenBvac (MenB group), or one dose of Menjugate and two doses of placebo (MenC group). Injection site reactions were frequent in all groups. However, most reactions were short lasting and mild or moderate in intensity, and the vaccines were found to be well tolerated, with no vaccine-related serious adverse events. MenB/C was immunogenic with regard to both serogroup B and C meningococci. Both the serum bactericidal assay and the enzyme-linked immunosorbent assay analyses showed that the immune responses of the combination vaccine were similar to the immune responses of its separate components MenBvac and Menjugate for both serogroup B and C. In conclusion, the combined MenB/C vaccine is safe and immunogenic. The two vaccines do not interact negatively with each other and can easily be administered in the same syringe. The induced immune responses suggest that the combined vaccine is likely to confer protection against systemic group B disease caused by the vaccine strain as well as against group C meningococcal disease. 相似文献
23.
Lee YJ Hohoff C Domschke K Sand P Kuhlenbäumer G Schirmacher A Freitag CM Meyer J Stöber G Franke P Nöthen MM Fritze J Fimmers R Garritsen HS Stögbauer F Deckert J 《Neuroscience letters》2005,377(1):40-43
Several biochemical and pharmacological studies suggest that the catecholaminergic system involving the norepinephrine transporter (NET) is relevant for the pathogenesis of panic disorder. Three single nucleotide polymorphisms in the promoter or untranslated 5' region of the NET gene were investigated by means of RFLP analysis in a sample of 115 German patients with panic disorder and 115 matched controls. Statistical analysis failed to show association with the overall diagnosis of panic disorder. In the subgroup of patients with panic disorder without agoraphobia, however, two polymorphisms were found to be associated with the disease (G/C (rs2397771): p < 0.05; T/C (rs2242446): p < 0.01). While our data do not support a major function of the NET gene in the development of panic disorder, it may play a role in the subgroup of panic disorder without agoraphobia. 相似文献
24.
25.
The principal vector of Borrelia burgdorferi, the Lyme borreliosis spirochete, in the Northeast and Midwestern regions of the United States is the blacklegged tick Ixodes scapularis. Because of a favorable environment, I. scapularis is also plentiful in the South; however, a correlation with Lyme borreliosis cases does not exist in this region of the United States. Concern existed that something intrinsic to ticks found in Louisiana could mitigate their ability to transmit B. burgdorferi. Therefore, we set out to assess the ability of I. scapularis ticks from Louisiana to become infected with and transmit B. burgdorferi using mice as hosts. In the laboratory, mating adult female ticks collected in southeastern Louisiana were fed on the ears of rabbits. After oviposition and egg hatching, the resulting larvae were fed on mice that had been needle-inoculated with two different strains of B. burgdorferi sensu stricto, B31 and JD1. Larvae were found to be positive for spirochetes. Additional fed larvae were allowed to molt into the nymphal stage. Flat nymphs remained infected with B. burgdorferi. Infected nymphs were allowed to feed on na?ve mice, all of which became infected as shown by culture of ear biopsy specimens. Na?ve larvae were then fed on these same mice to assess transmissibility. The resulting engorged larvae harbored spirochetes. We have demonstrated that the I. scapularis ticks found in Louisiana are fully competent to carry and transmit B. burgdorferi infection. 相似文献
26.
Autoimmunity and inflammation due to a gain-of-function mutation in phospholipase C gamma 2 that specifically increases external Ca2+ entry 总被引:3,自引:0,他引:3
Yu P Constien R Dear N Katan M Hanke P Bunney TD Kunder S Quintanilla-Martinez L Huffstadt U Schröder A Jones NP Peters T Fuchs H de Angelis MH Nehls M Grosse J Wabnitz P Meyer TP Yasuda K Schiemann M Schneider-Fresenius C Jagla W Russ A Popp A Josephs M Marquardt A Laufs J Schmittwolf C Wagner H Pfeffer K Mudde GC 《Immunity》2005,22(4):451-465
The identification of specific genetic loci that contribute to inflammatory and autoimmune diseases has proved difficult due to the contribution of multiple interacting genes, the inherent genetic heterogeneity present in human populations, and a lack of new mouse mutants. By using N-ethyl-N-nitrosourea (ENU) mutagenesis to discover new immune regulators, we identified a point mutation in the murine phospholipase Cg2 (Plcg2) gene that leads to severe spontaneous inflammation and autoimmunity. The disease is composed of an autoimmune component mediated by autoantibody immune complexes and B and T cell independent inflammation. The underlying mechanism is a gain-of-function mutation in Plcg2, which leads to hyperreactive external calcium entry in B cells and expansion of innate inflammatory cells. This mutant identifies Plcg2 as a key regulator in an autoimmune and inflammatory disease mediated by B cells and non-B, non-T haematopoietic cells and emphasizes that by distinct genetic modulation, a single point mutation can lead to a complex immunological phenotype. 相似文献
27.
Dr. U. Cordes B. Braun M. Georgi F. Kümmerle V. Lenner E. Magin T. Philipp J. Beyer 《Journal of molecular medicine (Berlin, Germany)》1979,57(22):1209-1215
Zusammenfassung Bei sechs Patienten mit adrenalem Phäochromocytom erfolgte die Lokalisationsdiagnostik durch Ultraschalluntersuchung, Phlebographie der Nebennieren und selektiver Katecholaminbestimmung im Blut der Vena cava sowie der Nebennierenvenen. Durch die selektive Katecholaminbestimmung konnten alle Phäochromocytome lokalisiert werden, durch die Ultraschalluntersuchung fünf, durch die Phlebographie vier. Ein Phäochromocytom von 1,5 g Gewicht, das nur durch die selektive Katecholaminbe-stimmung, nicht aber durch Ultraschall oder Phlebographie lokalisiert wurde, konnte computertomographisch dargestellt werden.Um Fehldiagnosen bei der selektiven Katecholaminbestimmung zu vermeiden, darf vor der Blutentnahme aus den Nebennierenvenen kein Röntgenkontrastmittel injiziert werden, da dies zu einer erheblichen Adrenalin- oder Noradrenalinfreisetzung aus dem Nebennierenmark führen kann. 相似文献
28.
Cation channels,cell volume and the death of an erythrocyte 总被引:8,自引:0,他引:8
Lang F Lang KS Wieder T Myssina S Birka C Lang PA Kaiser S Kempe D Duranton C Huber SM 《Pflügers Archiv : European journal of physiology》2003,447(2):121-125
Similar to a variety of nucleated cells, human erythrocytes activate a non-selective cation channel upon osmotic cell shrinkage. Further stimuli of channel activation include oxidative stress, energy depletion and extracellular removal of Cl–. The channel is permeable to Ca2+ and opening of the channel increases cytosolic [Ca2+]. Intriguing evidence points to a role of this channel in the elimination of erythrocytes by apoptosis. Ca2+ entering through the cation channel stimulates a scramblase, leading to breakdown of cell membrane phosphatidylserine asymmetry, and stimulates Ca2+-sensitive K+ channels, thus leading to KCl loss and (further) cell shrinkage. The breakdown of phosphatidylserine asymmetry is evidenced by annexin binding, a typical feature of apoptotic cells. The effects of osmotic shock, oxidative stress and energy depletion on annexin binding are mimicked by the Ca2+ ionophore ionomycin (1 µM) and blunted in the nominal absence of extracellular Ca2+. Nevertheless, the residual annexin binding points to additional mechanisms involved in the triggering of the scramblase. The exposure of phosphatidylserine at the extracellular face of the cell membrane stimulates phagocytes to engulf the apoptotic erythrocytes. Thus, sustained activation of the cation channels eventually leads to clearance of affected erythrocytes from peripheral blood. Susceptibility to annexin binding is enhanced in several genetic disorders affecting erythrocyte function, such as thalassaemia, sickle-cell disease and glucose-6-phosphate dehydrogenase deficiency. The enhanced vulnerability presumably contributes to the shortened life span of the affected erythrocytes. Beyond their role in the limitation of erythrocyte survival, cation channels may contribute to the triggering of apoptosis in nucleated cells exposed to osmotic shock and/or oxidative stress. 相似文献
29.
Joachim Ktz Mathias Hahn Burkart Philipp Esen A. Bekturov Sarkyt E. Kudaibergenov 《Macromolecular chemistry and physics.》1993,194(2):397-410
Employing polyampholytes (inclusively polybetaines) of different chemical structure containing carboxylic groups and various basic nitrogen functions, homosymplex formation, as well as the competition between homo- and heterosymplex formation on addition of an appropriate polyelectrolyte, was investigated in dependence of pH and ionic strength by means of viscometry and turbidimetry. With most, but not with all, of the polyampholytes, the expected viscosity minimum at the isoelectric point, with its steepness depending on polyampholyte structure, was observed. Competition of homo- and heterosymplex formation at and near the isoelectric point is mainly governed by the pK values of the species involved, the level of zwitter-ion formation of the polyampholyte and the effect of non-Coulombic interactions, for example, via hydrogen bonds. 相似文献
30.
13C NMR spectroscopic studies on polyanion-polycation complexes and their component polyelectrolytes
Joachim Ktz Andreas Ebert Jürgen Kunze Burkart Philipp Johan Lindberg Kari Soljamo 《Macromolecular chemistry and physics.》1990,191(3):651-658
Position and intensities of the 13C NMR signals and relaxation times T1 of several anionic and cationic polyelectrolytes in the solid state were compared with those of the appropriate polyanion-polycation complexes. At a high charge density of the components, the most significant changes of the parameters in question due to complex formation are observed for the C atoms adjacent to the charge centers, indicating a strong Coulombic interaction. At lower charge density, conformational changes of the polymer chains have also to be taken into consideration. 相似文献