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Population-based study of salivary carriage of periodontal pathogens in adults 总被引:2,自引:1,他引:1 下载免费PDF全文
Könönen E Paju S Pussinen PJ Hyvönen M Di Tella P Suominen-Taipale L Knuuttila M 《Journal of clinical microbiology》2007,45(8):2446-2451
Large, general population-based data on carriage rates of periodontal pathogens hardly exist in the current literature. The objectives of the present study were to examine the salivary detection of Aggregatibacter (formerly Actinobacillus) actinomycetemcomitans, Campylobacter rectus, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythensis, and Treponema denticola in a representative sample of the adult population living in southern Finland and to clarify which determinants are associated with the presence of these pathogens in saliva. 16S rRNA-based PCR methods with species-specific primers were employed to determine the presence of the six target bacteria in stimulated saliva samples, which were available from 1,294 subjects aged > or =30 years. The age group, gender, level of education, marital status, smoking history, number of teeth, and number of teeth with deepened pockets were included in the statistical analysis. In general, the carriage of periodontal pathogens was common, since at least one of the examined pathogens was found in 88.2% of the subjects. In descending order, the total detection rates were 56.9%, 38.2%, 35.4%, 31.3%, 20.0%, and 13.9% for T. forsythensis, T. denticola, P. gingivalis, C. rectus, A. actinomycetemcomitans, and P. intermedia, respectively. Age per se was strongly associated with the carriage of P. gingivalis (P = 0.000), and the level of education with that of T. denticola (P = 0.000). There was an association between the number of teeth with deepened pockets and carriage of P. gingivalis (P = 0.000), P. intermedia (P = 0.000), T. denticola (P = 0.000), and A. actinomycetemcomitans (P = 0.004). The data suggest that distinct species have a different carriage profile, depending on variables such as age, educational level, and periodontal status. 相似文献
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Enn K Seppet Margus Eimre Tiia Anmann Evelin Seppet Nadezhda Peet Tuuli Kmbre Kalju Paju Andres Piirsoo Andrei V Kuznetsov Marko Vendelin Frank N Gellerich Stephan Zierz Valdur A Saks 《Experimental & Clinical Cardiology》2005,10(3):173-183
BACKGROUND:
The present review examines the role of intra-cellular compartmentation of energy metabolism in vivo.OBJECTIVE:
To compare the kinetics of the activation of mitochondrial respiration in skinned cardiac fibres by exogenous and endogenous adenine nucleotides in dependence of the modulation of cellular structure and contraction.METHODS:
Saponin-permeabilized cardiac fibres or cells were analyzed using oxygraphy and confocal microscopy.RESULTS:
Mitochondria respiration in fibres or cells was upregulated by cumulative additions of ADP to the medium with an apparent Km of 200 μM to 300 μM. When respiration was stimulated by endogenous ADP produced by intracellular ATPases, a near maximum respiration rate was achieved at an ADP concentration of less than 20 μM in the medium. A powerful ADP-consuming system, consisting of pyruvate kinase and phosphoenolpyruvate, that totally suppressed the activation of respiration by exogenous ADP, failed to abolish the stimulation of respiration by endogenous ADP, but did inhibit respiration after the cells were treated with trypsin. The addition of up to 4 μM of free Ca2+ to the actively respiring fibres resulted in reversible hypercontraction associated with a decreased apparent Km for exogenous ADP. These changes were fully abolished in fibres after the removal of myosin by KCl treatment.CONCLUSIONS:
Mitochondria and ATPases, together with cytoskeletal proteins that establish the structural links between mitochondria and sarcomeres, form complexes – intracellular energetic units (ICEUs) – in cardiac cells. Within the ICEUs, the mitochondria and ATPases interact via specialized energy transfer systems, such as the creatine kinase- and adenylate kinase-phosphotransfer networks, and direct ATP channelling. Disintegration of the structure and function of ICEUs results in dyscompartmentation of adenine nucleotides and may represent a basis for cardiac diseases. 相似文献4.
Comparison of formation of reactive conformers for the SN2 displacements by CH3CO2- in water and by Asp124-CO2- in a haloalkane dehalogenase 总被引:1,自引:0,他引:1 下载免费PDF全文
Hur S Kahn K Bruice TC 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(5):2215-2219
The S(N)2 displacement of Cl(-) from 1,2-dichloroethane by acetate (CH(3)CO(2)(-)) in water and by the carboxylate of the active site aspartate in the haloalkane dehalogenase of Xanthobacter autothropicus have been compared by using molecular dynamics simulations. In aqueous solution, six families of contact-pair structures (I-VI) were identified, and their relative concentrations and dissociation rate constants were determined. The near attack conformers (NACs) required for the S(N)2 displacement reaction are members of the IV (CH(3)COO(-)...CH(2)(Cl)CH(2)Cl) family and are formed in the sequence II-->III-->IV-->NAC. The NAC subclass is defined by the COO(-)...CCl contact distance of < or = 3.41 A and the COO(-)...CCl angle of 157-180 degrees. The mole percentage of NACs is 0.16%, based on the 1 M standard state. This result may be compared with 13.4 mole percentage of NACs in the Michaelis complex in the enzyme. It follows that NAC formation in the enzyme is favored by 2.6 kcal/mol. Because reaction coordinates from S to TS, both in water and in the enzyme, pass via NAC (i.e., S --> NAC --> TS), the reduction in the S --> NAC barrier by 2.6 kcal/mol accounts for approximately 25% of the reduction of total barrier in the S --> TS (10.7 kcal/mol). The remaining 75% of the advantage of the enzymatic reaction revolves around the efficiency of NAC --> TS step. This process, based on previous studies, is discussed briefly. 相似文献
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The free beta-subunit of human chorionic gonadotropin as a prognostic factor in renal cell carcinoma
Hotakainen K Ljungberg B Paju A Rasmuson T Alfthan H Stenman UH 《British journal of cancer》2002,86(2):185-189
The free beta-subunit of human chorionic gonadotropin beta is expressed in several nontrophoblastic tumours and this is usually associated with aggressive disease. Little is known about human chorionic gonadotropin beta expression in renal cancer. We determined the pretreatment levels of human chorionic gonadotropin beta in serum of patients with renal cell carcinoma, and studied whether elevated levels predicted the clinical outcome. Serum samples were collected before surgery from 177 patients with renal cell carcinoma and from 84 apparently healthy controls. Human chorionic gonadotropin beta in serum was measured by a highly sensitive time-resolved immunofluorometric assay. The prognostic value of human chorionic gonadotropin beta, and of usual clinical and pathological variables was analyzed by the Kaplan-Meier method, the log rank test and Cox multiple hazard regression. The serum concentrations of human chorionic gonadotropin beta were increased in 23% of the renal cell carcinoma patients and they were significantly higher in patients with renal cell carcinoma than in controls (P<0.0001). The concentrations did not correlate with clinical stage and histopathological grade, but patients with increased human chorionic gonadotropin beta levels had significantly shorter survival time than those with levels below the median (cut-off 1.2 pmol l(-1), P=0.0029). In multivariate analysis human chorionic gonadotropin beta, tumour stage and grade were independent prognostic variables. The serum concentration of human chorionic gonadotropin beta is an independent prognostic variable in renal cell carcinoma. The preoperative value of human chorionic gonadotropin beta in serum may be used to identify patents with increased risk of progressive disease. 相似文献
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PURPOSE: We analyzed the prognostic significance of pretreatment serum tumor associated trypsin inhibitor in renal cell carcinoma. MATERIALS AND METHODS: Serum samples were obtained before surgery from 188 patients who underwent radical nephrectomy for renal cell carcinoma. Median followup of living patients was 8.5 years. Serum tumor associated trypsin inhibitor was measured by a time resolved immunofluorometric assay. Statistical analysis was performed using the Kaplan-Meier method, log rank and stratified log rank tests. RESULTS: Preoperatively serum tumor associated trypsin inhibitor was elevated with a cutoff 16 microg/l in 48% of the patients with normal serum creatinine. The concentration in patients with cancer was significantly higher than in controls (p <0.0001). The serum level correlated with clinical stage and nuclear grade. Patients with an elevated level had significantly shorter survival time than those with a normal level (p = 0.005). Stratified log rank test demonstrated that tumor associated trypsin inhibitor was a prognostic factor independent of stage and grade in all patients as well as in those with nonmetastatic disease. CONCLUSIONS: Increased preoperative serum tumor associated trypsin inhibitor was associated with poor survival in renal cell carcinoma. The serum level was an independent prognostic variable. Preoperative serum tumor associated trypsin inhibitor appears to be a useful predictive factor that may be used to identify patients at increased risk of aggressive disease. 相似文献
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Herpesviruses in brains in Alzheimer's and Parkinson's diseases 总被引:4,自引:0,他引:4
Hemling N Röyttä M Rinne J Pöllänen P Broberg E Tapio V Vahlberg T Hukkanen V 《Annals of neurology》2003,54(2):267-271
We evaluated the association of HSV-1, HHV-6, and VZV with Alzheimer's disease (AD) and Parkinson's disease (PD). Brain specimens for viral DNA polymerase chain reaction represented 34 patients with AD, 40 with PD, and 40 controls. One AD patient (2.9%) was positive for HSV-1 DNA, 88.2% for HHV-6 DNA, and 26.5% for VZV DNA; 17.5% of PD patients were HSV-1 DNA-positive and 75% HHV-6-positive, whereas 40% had VZV DNA. Twenty-five percent of the controls were positive for HSV-1 DNA, 87.5% for HHV-6, and 27.5% for VZV. HSV-1, VZV, or HHV-6 DNA in brains was no additional risk factor for AD. 相似文献
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