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81.
Neonatal exposure to monosodium glutamate induces morphological alterations in suprachiasmatic nucleus of adult rat 下载免费PDF全文
Julio César Rojas‐Castañeda Rosa María Vigueras‐Villaseñor Margarita Chávez‐Saldaña Patricia Rojas Oscar Gutiérrez‐Pérez Carolina Rojas Marcela Arteaga‐Silva 《International journal of experimental pathology》2016,97(1):18-26
Neonatal exposure to monosodium glutamate (MSG) induces circadian disorders in several physiological and behavioural processes regulated by the suprachiasmatic nucleus (SCN). The objective of this study was to evaluate the effects of neonatal exposure to MSG on locomotor activity, and on morphology, cellular density and expression of proteins, as evaluated by optical density (OD), of vasopressin (VP)‐, vasoactive intestinal polypeptide (VIP)‐ and glial fibrillary acidic protein (GFAP)‐immunoreactive cells in the SCN. Male Wistar rats were used: the MSG group was subcutaneously treated from 3 to 10 days of age with 3.5 mg/g/day. Locomotor activity was evaluated at 90 days of age using ‘open‐field’ test, and the brains were processed for immunohistochemical studies. MSG exposure induced a significant decrease in locomotor activity. VP‐ and VIP‐immunoreactive neuronal densities showed a significant decrease, while the somatic OD showed an increase. Major axes and somatic area were significantly increased in VIP neurons. The cellular and optical densities of GFAP‐immunoreactive sections of SCN were significantly increased. These results demonstrated that newborn exposure to MSG induced morphological alterations in SCN cells, an alteration that could be the basis for behavioural disorders observed in the animals. 相似文献
82.
Cellular mechanisms of the adjuvant activity of the flagellin component FljB of Salmonella enterica Serovar Typhimurium to potentiate mucosal and systemic responses 总被引:1,自引:0,他引:1 下载免费PDF全文
An expanding area of interest is the utilization of microbe-based components to augment mucosal and systemic immune responses to target antigens. Thus, the aim of the present study was to assess if the flagellin component FljB from Salmonella enterica serovar Typhimurium could act as a mucosal adjuvant and then to determine the cellular mechanism(s) by which FljB mediates its adjuvant properties. To determine if FljB could act as a mucosal adjuvant, mice were immunized by the intranasal (i.n.) route with antigen alone or in conjunction with FljB. Additionally, we assessed how FljB affected the levels of the costimulatory molecules B7-1 and B7-2 on dendritic cells by flow cytometry and determined the functional role these costimulatory molecules played in the adjuvant properties of FljB in vivo. Mice immunized by the i.n. route with antigen and FljB exhibited significantly elevated levels of mucosal and systemic antibody and CD4(+)-T-cell responses compared to mice given antigen only. Stimulation of dendritic cells in vitro with FljB resulted in a pronounced increase in the surface expression of B7-1 and B7-2. The percentage of dendritic cells expressing B7-2 but not B7-1 increased significantly when stimulated with FljB over a concentration range of 10 to 10,000 ng/ml. Immunization of wild-type and B7-1, B7-2, and B7-1/2 knockout mice by the i.n. route revealed that the ability of FljB to increase B7-2 expression is largely responsible for its adjuvant effect in vivo. These findings demonstrate that FljB can act as an effective mucosal adjuvant and that its ability to enhance the level of B7-2 expression is predominantly responsible for its adjuvant properties. 相似文献
83.
Montes-Rodríguez CJ Alavez S Elder JH Haro R Morán J Prospéro-García O 《Neuroscience letters》2004,360(3):133-136
The human immunodeficiency virus (HIV) induces neuronal death, presumably by apoptosis. This effect may be triggered by the glycoprotein 120 (HIVgp120) released by HIV when infecting a cell, and mediated by tumor necrosis factor alpha (TNF), a pro-inflammatory cytokine. Both molecules, HIVgp120 and TNF, increase sleep when administered acutely in the brain. On the other hand, sleep deprivation increases the levels of several growth factors. In this context, we challenged rats with HIVgp120 or TNF simultaneously with sleep deprivation. Our results indicate that both HIVgp120 and TNF increase neuronal death in the rat cerebral cortex, but not hippocampus, and that this effect is completely prevented by total deprivation of sleep. These results suggest that acute total deprivation of sleep protects against the HIVgp120 and TNF deleterious effects. 相似文献
84.
Antibodies produced in response to Cryptococcus neoformans pulmonary infection in mice have characteristics of nonprotective antibodies 总被引:1,自引:0,他引:1 下载免费PDF全文
Murine cryptocococcal pulmonary infection elicited serum immunoglobulin M (IgM) and IgG to the capsular polysaccharide, but only IgG stained yeast cells in alveoli. Both isotypes produced punctuate immunofluorescence patterns on yeast cells like those of nonprotective antibodies. The difficulties involved in associating humoral immunity with protection in murine cryptocococcal infection could reflect nonprotective antibody responses. 相似文献
85.
Yuzo Hirota Oscar H.L. Bing Walter H. Abelmann 《Journal of molecular and cellular cardiology》1976,8(9):727-732
The effects of ethanol on myocardial mechanical properties were evaluated in isolated rat ventricular muscle preparations. Ethanol reduced peak developed tension by 6.3% at a concentration of , 11.8% at and 27.2% at . A similar degree of depression was observed in . Time to peak tension was slightly shortened, and isometric relaxation rate was increased at a high concentration of ethanol. The resting tension did not change significantly.Despite biochemical data by others suggesting an alcohol induced delay in calcium sequestration by cardiac microsomes, ethanol at concentrations found in human intoxication depressed the systolic performance of isolated muscle preparations but did not prolong relaxation or alter resting tension. 相似文献
86.
Seven DNA polymorphisms in the LDL receptor gene: application to the study of familial hypercholesterolemia in Spain 总被引:1,自引:0,他引:1
F. Javier Chaves Oscar Puig Magdalena Garcia-Sogo José Real José V. Gil Juan Ascaso Rafael Carmena M. Eugenia Armengod 《Clinical genetics》1996,50(1):28-35
We have performed restriction fragment length polymorphism (RFLP) analysis at the low density lipoprotein receptor (LDLR) locus in order to investigate the molecular genetics of familial hypercholesterolemia (FH) in Spain. Firstly, a sample of 50 unrelated patients with a clinical diagnosis of FH was screened for the presence of major rearrangements at this locus by Southern blot analysis of Bgt II digested genomic DNA. Four different mutations were detected, accounting for 8% of the mutant alleles in the Spanish FH sample. Then, we determined the relative allele frequency and estimated linkage disequilibrium between seven RFLPs of the LDLR gene in the remaining 46 FH patients and in 61 normolipidemic controls. Hindi, Avail, Pvu II, Msp I, and Nco I are the most polymorphic sites with individual PIC values higher than 0.28, whereas the Taq I and Stu I sites display low levels of polymorphism. The usefulness of the seven RFLPs to confirm a clinical diagnosis of FH was investigated in 15 FH-families, consisting of 118 individuals, in whom the presence of Familial Defective Apolipoprotein B-100 (FDB) due to the apoB3500 mutation was excluded. Independent haplotypes were constructed for 71 chromosomes: 15 FH and 56 control haplotypes. A total of 14 different haplotypes was found. In 12 families, clinical diagnosis of FH was confirmed by cosegregation analysis, which makes these RFLPs useful for studying the inheritance of the LDLR gene in 80% of Spanish families with FH. Comparison of haplotypes found in the Spanish sample with those found in Swiss and Norwegians suggests heterogeneity of haplotypes among European populations. 相似文献
87.
An accession of Vitis vinifera cv. Red Globe from Argentina, was found to be infected with Grapevine leafroll-associated virus-5 by ELISA. It was partially sequenced, and three ORFs, corresponding to HSP70h, HSP90h, and CP, were found. This isolate shares a high aminoacid identity with the previously reported sequence of the virus, and identities between 80% and 90% with previously reported GLRaV-9 and GLRaV-4 isolates. The analysis of the sequence supports the clustering together with GLRaV-4 and GLRV-9 inside the Ampelovirus genus. 相似文献
88.
da Silva JM Andrade Junior CV Zaia AA Pessoa OF 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2011,111(2):260-264
This study evaluated cleaning of the dentinal wall after removal of different calcium hydroxide pastes. Sixty-eight single-rooted teeth were prepared using the step-back technique and randomly divided into 4 groups according to medication used: Ca(OH)2 with 0.2% chlorhexidine solution (Group 1), Ca(OH)2 with propylene glycol (Group 2), Ca(OH)2 with antibiotic paste (ciprofloxacin, metronidazole) and distilled water (Group 3), and Ca(OH)2 with antibiotic paste and propylene glycol (Group 4). The samples were stored at 37 °C and 100% relative humidity for 21 days. The medicaments were removed using 5 mL 1% NaOCl, instrumentation with master apical file, 5 mL 1% NaOCl, patency with the K-file #10, ultrasonic instrumentation, and 10 mL 17% EDTA-T. The specimens were analyzed using scanning electron microscopy and chemical analysis. The Kruskal-Wallis (α = 5%) test showed that were no differences between the experimental groups when comparing Ca(OH)2 removal (P = .0951). The chi-square test (α = 5%) indicated a predominance of Ca(OH)2 obstructing dental tubules in all groups. On the basis of the methodology applied, it was concluded that the apical dentine surface remained equally covered by Ca(OH)2, regardless of the vehicle used. 相似文献
89.
Daniel M. Saman MPH Oscar Arevalo DDS ScD MBA MS Andrew O. Johnson PhD 《Journal of public health dentistry》2010,70(3):188-196
Objectives: This study assessed the geographic distribution of dentists in Kentucky, determined socioeconomic correlates of practice location, estimated the future availability of dental providers, and made policy recommendations that could improve access to oral health care in Kentucky and other rural states. Methods: Dentists' addresses were mapped using a geographic information system. Poisson regression modeling and geospatial analyses were conducted using SAS v9.1 (SAS Institute, Cary, NC, USA) and ArcGIS v9.2 (Environmental Systems Research Institute Inc., Redlands, CA, USA), respectively. Data on the number of dentists (n = 2,391) per county (n = 120) were used for the regression models. Explanatory variables included: per capita income, 2006 intercensal population estimates, percent adults with six or more teeth removed, percent population uninsured, physician‐to‐population ratios, and region type. A simulation model was used to project dentist‐to‐population ratios to the year 2016. Results: The dental workforce analysis revealed disparities in the distribution of dentists between rural, urban, and Appalachian Kentucky counties. Dentists were more likely to be found practicing in areas with higher income and higher physician‐to‐population ratios. Compounding this geographic maldistribution, our projections suggest that the number of dentists per unit population will decrease over time in the near future, likely widening this disparity in rural and underserved areas. Conclusions: These results show present and widening workforce disparities in rural and socioeconomically depressed counties in Kentucky. Understanding the geographic distribution of dentists and the socioeconomic correlates of their practice locations may inform workforce development and reimbursement policies for the goal of improving access to oral health care in these areas. 相似文献
90.
Matthew E. Harinstein MD Oscar C. Marroquin MD 《Catheterization and cardiovascular interventions》2014,83(3):E168-E170
Acute coronary syndromes in the setting of infective endocarditis may be the result of coronary compression secondary to periannular aortic valve complications, coronary embolism, obstruction of the coronary ostium due to a large vegetation, coronary atherosclerosis, and severe aortic insufficiency. External coronary artery compression as a result of infective endocarditis is a rare and lethal finding with few reported cases available in the medical literature. We present a rare occurrence of an acute coronary syndrome occurring in the setting of a bioprosthetic aortic valve abscess in which there was no complete coronary occlusion visualized and given the patient's recent unremarkable catheterization and findings of diffuse tapering of the proximal left coronary system, the most likely etiology was external compression secondary to the known aortic root abscess, which caused myocardial ischemia, and was confirmed during surgery. Although uncommon, external compression should be considered in the differential diagnosis of acute coronary syndrome in this setting and coronary angiography can be diagnostic of this entity.© 2012 Wiley Periodicals, Inc. 相似文献