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Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120, 1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320, respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections. Received: 10 April 2000 / Accepted: 18 July 2000  相似文献   
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The polymorphic nature of the immunoglobulin VH genes was investigated by Southern blot analysis of liver DNA of sixteen different mouse strains and hybridization with VH probes. Differences in restriction enzyme pattern (REP) were observed and six different patterns of restriction fragments were found for the sixteen strains analyzed. No equivalent polymorphism was observed in another multigene family, the actins. The six patterns correlate with immunoglobin constant region allotypes (Igh-1). Experiments with Igh-1-congenic strains suggest that the VH REP is linked to immunoglobulin constant region haplotype. Mouse strains which share inherited idiotypes also share identical VH restriction pattern. This provides a structural basis for the genetic linkage between idiotypes and allotypes. It also indicates that different strains carry different VH gene repertoires, which may be the basis for the expression of different inherited idiotypes in various strains. We propose that a VH group is a set of linked genes that are coinherited as a cluster with the constant region genes and that VH and CH can be regarded as an extended haplotype.  相似文献   
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Researchers have differentiated sons of alcoholics (SOA's) from sons of nonalcoholics (non-SOA's) on various measures of physiological activity that appear to be related to the SOA's increased vulnerability to developing alcohol problems. This article summarizes major findings in the literature and discusses the implications of risk-related physiological characteristics for the future development of alcohol problems. SOA's tend to show signs of physiological activity associated with anxiety states, such as increased heart rate in response to stressful stimuli. Studies also demonstrate that SOA's differ greatly from non-SOA's in their response to alcohol. Drinking alcohol dramatically reduces SOAs' reactivity to both stressful and nonstressful stimuli. Additionally, SOA's appear to be less sensitive to alcohol's intoxicating and impairing effects. However, studies also suggest that some SOA's may experience more of alcohol's rewarding effects for a brief period after drinking. Increased stress-dampening and reduced responsiveness to alcohol's negative effects also appear to predict the development of future alcohol problems and may reflect important vulnerabilities in SOA's.  相似文献   
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Vitrectomy for macular pucker and vitreomacular traction syndrome   总被引:3,自引:0,他引:3  
During the course of a so-called posterior vitreous detachment, a thin layer of the posterior vitreous cortex often remains adherent to the underlying retina. Tangential stretch of this vitreous pseudomembrane may cause vitreomacular traction syndrome, edema, and macular hole formation. The same process appears to underlie the development of true epimacular membranes (idiopathic macular pucker). Vitrectomy is generally agreed to be the most appropriate treatment for these clinical situations. We evaluated the incidence of vitreomacular adhesion and of visual improvement after vitrectomy of eyes with macular pucker (group 1; n=60) and vitreomacular traction syndrome (group 2; n=50). Vitreomacular attachment was assessed during vitrectomy under the condition of continuous air infusion. In the two groups, complete or partial vitreous attachment to the macula was observed in 57.4% and 74%, respectively. We conclude that vitreomacular adhesion is a common feature of the two clinical situations. Visual improvement was achieved in 73% of both groups. High rates of postoperative visual acuities of 20/50 or better (60.6% in group-1; 65.7% in group-2 cases) occurred only in eyes with preoperative values of 20/100 or better. It is reported that the visual outcome of vitreoretinal surgery for the two clinical conditions deteriorates with increasing duration after initial manifestation. Vitrectomy should not be postponed in patients who complain of disturbing visual symptoms such as reduced visual acuity, metamorphopsia and disturbance of binocular reading. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Background  

Human immunodeficiency virus (HIV)-1 infection increases the burden of malaria by increasing susceptibility to infection and decreasing the response to malarial treatment. HIV-1 has also been found to suppress the immune system and predispose to severe forms of malaria in adults. There is still a paucity of data on the association between HIV-1 infection and cerebral malaria in children. The aim of this study was to determine whether HIV-1 infection is a risk factor for cerebral malaria in children.  相似文献   
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AIDS and Behavior - Although misperceived norms often drive personal health behaviors, we do not know about this phenomenon in the context of antiretroviral therapy (ART) adherence. We conducted a...  相似文献   
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BACKGROUND: Recent research suggests that a reduced P300 amplitude of the event-related potential is associated with a vulnerability to alcoholism. This study tested the hypothesis that reductions in the P300 amplitude would be associated with specific dimensions of disinhibited personality (social deviance proneness and impulsivity) and that these personality traits would mediate the association between P300 and alcohol problems in a young adult sample that varied widely in disinhibitory traits. METHODS: Alcohol problems, personality (impulsivity, social deviance, harm avoidance, and excitement seeking), and event-related potentials were measured in a sample of 190 subjects (87 men, 103 women) with a mean age of 20.7 +/- 1.9 years. RESULTS: Social deviance, impulsivity, and alcohol problems were associated with reductions in the P300, but only in male subjects. A structural model suggested that social deviance, impulsivity, and alcohol problems were all strongly related to P300 amplitude at Fz. Further analyses indicated that for male subjects, social deviance mediated the association between P300 at Fz and alcohol problems as well as the association between impulsivity and alcohol problems. CONCLUSIONS: This study suggests that reduced P300s are strongly associated with a general tendency toward antisocial, defiant, and impulsive traits, which might, in turn, increase the risk for alcohol abuse. The lack of an association between reduced P300s and personality or alcohol problems in women was unexpected and deserves further study.  相似文献   
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BackgroundThe randomized SOLVE-TAVI (compariSon of secOnd-generation seLf-expandable vs. balloon-expandable Valves and gEneral vs. local anesthesia in Transcatheter Aortic Valve Implantation) trial compared newer-generation self-expanding valves (SEV) and balloon-expandable valves (BEV) as well as local anesthesia with conscious sedation (CS) and general anesthesia (GA) in patients undergoing transfemoral transcatheter aortic valve replacement (TAVR). Both strategies showed similar outcomes at 30 days.ObjectivesThe purpose of this study was to compare clinical outcomes during 1-year follow-up in the randomized SOLVE-TAVI trial.MethodsUsing a 2 × 2 factorial design 447 intermediate- to high-risk patients with severe, symptomatic aortic stenosis were randomly assigned to transfemoral TAVR using either the SEV (Evolut R, Medtronic Inc., Minneapolis, Minnesota) or the BEV (Sapien 3, Edwards Lifesciences, Irvine, California) as well as CS or GA at 7 sites.ResultsIn the valve-comparison strategy, rates of the combined endpoint of all-cause mortality, stroke, moderate or severe paravalvular leakage, and permanent pacemaker implantation were similar between the BEV and SEV group (n = 84, 38.3% vs. n = 87, 40.4%; hazard ratio: 0.94; 95% confidence interval: 0.70 to 1.26; p = 0.66) at 1 year. Regarding the anesthesia comparison, the combined endpoint of all-cause mortality, stroke, myocardial infarction, and acute kidney injury occurred with similar rates in the GA and CS groups (n = 61, 25.7% vs. n = 54, 23.8%; hazard ratio: 1.09; 95% confidence interval: 0.76 to 1.57; p = 0.63).ConclusionsIn intermediate- to high-risk patients undergoing transfemoral TAVR, newer-generation SEV and BEV as well as CS and GA showed similar clinical outcomes at 1 year using a combined clinical endpoint. (SecOnd-generation seLf-expandable Versus Balloon-expandable Valves and gEneral Versus Local Anesthesia in TAVI [SOLVE-TAVI]; NCT02737150)  相似文献   
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