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921.
922.
Objective. Crohn's disease (CD) and ulcerative colitis (UC) are characterized by an impaired mucosal defence to normal constituents of the intestinal flora and a dysregulated inflammatory response. The purpose of the study was to investigate whether single nucleotide polymorphisms (SNPs) in genes involved in these processes were associated with CD and UC. Material and methods. Allele frequencies of the cyclooxygenase 2 (COX-2/PTGS2/PGHS2) G-765C and breast cancer resistance protein (BCRP/ABCG2) C421A as well as allele and haplotype frequencies of multidrug resistance 1 (MDR1, ABCB1) SNPs G2677T/A, C3435T and G-rs3789243-A (intron 3) were assessed in a Danish case-control study comprising 373 CD and 541 UC patients and 796 healthy controls. Results. Carriers of the homozygous COX-2 and MDR1 intron 3 variant had a relatively high risk of CD, odds ratio (95% CI) (OR (95% CI))=2.86 ((1.34–5.88) p=0.006) and 1.39 ((0.99–1.92) p=0.054), respectively, and for UC of 2.63 ((1.33–5.26) p=0.005) and 1.28 ((0.96–1.51) p=0.093), respectively, assuming complete dominance. No association was found for BCRP or other MDR1 SNPs, or for selected MDR1 haplotypes. No effect-modification of smoking habit at the time of diagnosis was found. Conclusions. An effect of the COX-2 polymorphism on both CD and UC was shown which is compatible with the presence of a recessive allele in linkage equilibrium with the SNP marker in the COX-2 gene. The polymorphism located in intron 3 of the MDR1 gene showed a weak association with CD, and a marginally suggestive association with UC.  相似文献   
923.
Objective: The aim of this clinical quality study was to determine whether the aseptic working field is maintained during the endodontic procedure.

Materials and methods: Bacterial samples were collected from the rubber dam of 27 patients during endodontic treatment performed by postgraduate students at the Department of Endodontics, University of Oslo. A bacterial sample was first obtained immediately after disinfection of the working field (A), and the second sample was collected just before obturation or dressing with calcium hydroxide cement (B). Aerobic cultivation technique and PCR were used for detection of bacterial growth and species.

Results: All samples were negative on culturing except in one case, which showed positive results with cultivation in both sample A and B. Specie detected with cultivation technique were Streptococcus mitis. With PCR technique, 6 samples in 5 patients (11%), showed positive results. Species detected with PCR technique were Bacteroidales spp. Propionibacterium spp., Bacteroidetes spp., Prevotella nigrescens, Haemophilus parainfluenzae, Neisseria elongata, Alloprevotella tannerae, Capnocytophaga granulosa, Cardiobacterium hominis, Fusobacterium nucleatum and Streptococcus mitis.

Conclusion: The present study showed that an aseptic working field was maintained throughout the endodontic procedure in 81% (22/27) of the cases after disinfection of the rubber dam.  相似文献   
924.
Familial Mediterranean fever (FMF), inherited in an autosomal recessive manner, is a systemic auto‐inflammatory disorder characterized by recurrent attacks of fever with peritonitis, pleuritis, synovitis and erysipeloid rash. The marenostrin‐encoding fever (MEFV) gene, located on chromosome 16p13.3, is the only gene in which mutations are currently known to cause FMF. To correlate specific genotypes with adverse phenotypes of affected populations residing in the Western United States, a retrospective case series review was conducted of all MEFV gene mutation testing completed at UCLA Clinical Molecular Diagnostic Laboratory between February 2002 and February 2012, followed by clinical chart review of all subjects who either have a single or double mutation. All 12 common mutations in the MEFV gene were analyzed and the M694V variant was found to be associated with an adverse FMF clinical outcome in the Armenian‐American population, manifested by earlier onset of disease, increased severity of disease, and renal amyloidosis.  相似文献   
925.
Objective - To examine children aged 7-15 years with parentally reported episodes of wheeze in order to estimate the proportion of undiagnosed asthmatics in this group. Design - A cross-sectional study with clinical examination of subgroups. Setting - All children (n=832) aged 7-15 years in the municipality of Odda. Subject - Based on completed questionnaires, the children were selected to one of four groups: Children with wheeze but no asthma (wheeze group); children with current asthma (asthma group); children with past asthma (past asthma group); and children with neither asthma nor wheeze (control group). Main outcome measures - Parental reports of episodes of wheeze, assessment of skin prick test sensitivity, measures of lung function and exercise -induced bronchoconstriction (EIB). Results - In the wheeze group, 3 (7.5%) of 40 children were diagnosed with asthma in the 18-month period between the questionnaire survey and the examination, while 4 (10%) other children had EIB. Another 8 children (20%) reported 3 episodes of wheeze or more, and at least 1 episode during the 12-month period before the clinical examination. Classifying these children as asthmatics would give a proportion of 37.5% with undiagnosed asthma in the wheeze group, and the prevalence of current asthma among children aged 7-15 would rise from 2.9% based on a questionnaire survey to 4.9%. Conclusions - Using a wide definition of asthma, this study suggests that a large proportion of Norwegian children with wheeze actually have asthma.  相似文献   
926.
927.
Introduction: Sudden unexplained death account for one‐third of all sudden natural deaths in the young (1–35 years). Hitherto, the prevalence of genopositive cases has primarily been based on deceased persons referred for postmortem genetic testing. These deaths potentially may represent the worst of cases, thus possibly overestimating the prevalence of potentially disease causing mutations in the 3 major long‐QT syndrome (LQTS) genes in the general population. We therefore wanted to investigate the prevalence of mutations in an unselected population of sudden unexplained deaths in a nationwide setting. Methods: DNA for genetic testing was available for 44 cases of sudden unexplained death in Denmark in the period 2000–2006 (equaling 33% of all cases of sudden unexplained death in the age group). KCNQ1, KCNH2, and SCN5A were sequenced and in vitro electrophysiological studies were performed on novel mutations. Results: In total, 5 of 44 cases (11%) carried a mutation in 1 of the 3 genes corresponding to 11% of all investigated cases (R190W KCNQ1, F29L KCNH2 (2 cases), P297S KCNH2 and P1177L SCN5A). P1177L SCN5A has not been reported before. In vitro electrophysiological studies of P1177L SCN5A revealed an increased sustained current suggesting a LQTS phenotype. Conclusion: In a nationwide setting, the genetic investigation of an unselected population of sudden unexplained death cases aged 1–35 years finds a lower than expected number of mutations compared to referred populations previously reported. We therefore conclude that the prevalence of mutations in the 3 major LQTS associated genes may not be as abundant as previously estimated. (J Cardiovasc Electrophysiol, Vol. 23 pp. 1092‐1098, October 2012)  相似文献   
928.
929.
The majority of cystic fibrosis (CF) patients acquire chronic Pseudomonas aeruginosa lung infection, resulting in increased mortality and morbidity. The chronic P. aeruginosa lung infection is characterized by bacteria growing in biofilm surrounded by polymorphonuclear neutrophils (PMNs). However, the infection is not eradicated and the inflammatory response leads to gradual degradation of the lung tissue. In CF patients, a Th2‐dominated adaptive immune response with a pronounced antibody response is correlated with poorer outcome. Dendritic cells (DCs) are crucial in bridging the innate immune system with the adaptive immune response. Once activated, the DCs deliver a set of signals to uncommitted T cells that induce development, such as expansion of regulatory T cells and polarization of Th1, Th2 or Th17 subsets. In this study, we characterized DCs in lungs and regional lymph nodes in BALB/c mice infected using intratracheal installation of P. aeruginosa embedded in seaweed alginate in the lungs. A significantly elevated concentration of DCs was detected earlier in the lungs than in the regional lymph nodes. To evaluate whether the chronic P. aeruginosa lung infection leads to activation of DCs, costimulatory molecules CD80 and CD86 were analyzed. During infection, the DCs showed significant elevation of CD80 and CD86 expression in both the lungs and the regional lymph nodes. Interestingly, the percentage of CD86‐positive cells was significantly higher than the percentage of CD80‐positive cells in the lymph nodes. In addition, cytokine production from Lipopolysaccharides (LPS)‐stimulated DCs was analyzed demonstrating elevated production of IL‐6, IL‐10 and IL‐12. However, production of IL‐12 was suppressed earlier than IL‐6 and IL‐10. These results support that DCs are involved in skewing of the Th1/Th2 balance in CF and may be a possible treatment target.  相似文献   
930.
Background: Cardiovascular mortality is high in end stage renal disease (ESRD). This study aimed to: (1) calculate within-week within- and between-subject biological variation (CVI and CVG) for hs-cTn in ESRD; (2) determine the magnitude of hs-cTn concentration changes during haemodialysis (HD) treatment; and (3) compare the CVI and CVG to the within and between-subject variation of cTn concentration changes during HD treatments (CVDIFF-I and CVDIFF-G).

Methods: Serum samples were collected from 20 patients before and after 10 consecutive HD treatments. cTn were measured using the hs-cTnT (Roche Diagnostics) and the hs-cTnI (Abbott Diagnostics). The CVA, CVI, CVG, CVDIFF-I and CVDIFF-G, were estimated using nested ANOVA.

Results: The within-week data showed hs-cTnT CVA, CVI and CVG of 1.6, 7.3 and 94.4%. Reference change values (RCV) were estimated to ?18.7–23.0%. The Index of individuality (II) was 0.08. Corresponding values for hs-cTnI were 5.3, 13.2 and 142.4%, whilst the RCV was ?32.5–48.2% and the II was 0.10. The mean concentration of cTn decreased by ?6.4% (hs-cTnT) and ?7.6% (hs-cTnI) during HD treatment. The CVDIFF-I and CVDIFF-G was 4.2 and 6.3% for hs-cTnT, and 10.7 and 9.4% for hs-cTnI. The RCVDIFF was ?18.2–5.4% (hs-cTnT) and ?39.0–23.8% (hs-cTnI), respectively, and the IIDIFF-values were 0.7 and 1.3.

Conclusions: The CVI and CVG are similar to earlier findings. Mean hs-cTn concentrations decreased during HD. The within-subject hs-cTn variation during HD is similar to the between-subject variation, i.e. determining a cut-off value for hs-cTn changes during HD may be useful.  相似文献   
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