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排序方式: 共有146条查询结果,搜索用时 15 毫秒
1.
OBJECTIVE: In our previous study, auditory event-related potentials (AERPs) in preterm 1-year-old children had a positive deflection at 150-350 ms that correlated positively with their 2-year neurodevelopmental outcome. In a study of the same subjects at age 5, our aim was to assess AERPs and their relationship to neuropsychological test results. METHODS: Preterm small (SGA, n=13), appropriate for gestational age (AGA, n=15), and control (n=13) children were assessed with an Easy paradigm presenting a large frequency change accompanied with occasional novel sounds, and a Challenging paradigm presenting small frequency and duration changes with a rapid rate. The preterm children underwent neurocognitive tests. RESULTS: Easy paradigm. The P1 response to frequency deviant was smaller and MMN larger in the preterm than in the control children. Challenging paradigm. The P1 response to standard, frequency, and duration deviants was smaller in the preterm than in the control children. The N2 response to frequency deviant was larger in the preterm than in the control children. AGA and SGA children had similar AERPs. The P1, N2, and MMN amplitudes correlated with verbal IQ and NEPSY language subtests. CONCLUSIONS: Small P1 response(s) appears to be typical for preterm children. SIGNIFICANCE: Small P1 response in preterm children may suggest altered primary auditory processing.  相似文献   
2.
The metabolism of chemical carcinogens was investigated in liverpreparations from 28 captive woodchucks (Marmotamonax). Of these,23 were naturally infected with the wood-chuck hepatitis virus(WHV), and eight also had primary hepatocellular carcinoma (PHC).Twenty-nine parameters were investigated in liver subcelhilarfractions, including cross-reactivity with HBsAg, and biochemicalparameters, such as -glutamyl transpeptidase, cytochrome P-450and mirosomal monooxygenases (aryl hydrocarbon hydroxylase,ethodycoumarin and ethoxyresorufin deethylases, amino-pyrineand dimethylnitrosamine demethylases, and testosterone 7-and16ß- and 6ß-hydroxylases), uridine 5'-diphos-phoglucuronosyltransferase, GSH and related enzymes (peroxidase, reductaseand S-transferase), as well as other cytosolic enzyme activities(glucose 6-phosphate and 6-phosphogluconate dehydrogenases,NADPH- and NADH-dependent diaphorases, and DT diaphorase). Inaddition, liver preparations were used in order to quantifythe metabolic activation into bacterial mutagens of five procarcinogens(aflatoxin B1, the pyrolysis products Trp-P-2 and MelQ, 2-aminofluoreneand dimethylnitrosamine) and the decrease of potency of threedirect-acting mutagens (sodium di-chromate, ICR 191 and 4-nitroquinoline1-oxide). WHV infection produced a significant stimulation ofcarcinogen metabolism, as shown by the simultaneous change indetoxification parameters (GSH depletion) and activation indices(enhancement of microsomal monooxygenases and of pro-carcinogenactivation into mutagenic metabolites). There were no significantdifferences between WHV-positive samples from animals, withoutPHC and the noncancerous tissue of PHC-bearing animals, whereasa decrease of both activation and detoxification indices wasrecorded in the turmorous tissue. There was a considerable interindividualvariability among WHV carriers, which was tentatively ascribedto genetic factors. Pregnancy was the only known factor influencingthe results in WHV carriers. However, even by excluding pregnantanimals, the effects on carcinogen metabolism produced by WHVinfection were still statistically significant. These results,together with previous data obtained in humans, revealed thatmetabolic factors may play a role in the synergism between viralhepatitis and chemical hepato-carcinogens in the etiopathogenesisof PHC.  相似文献   
3.
The contribution of cytochrome P-450 isozymes to benzene metabolismin liver microsomes from fed, fasted, pyrazole-, pbenobarbital(PB)- and ethanol-treated rats and in respective isocaloriccontrols was investigated using monoclonal antibodies (mAbs).Clone 1-7-1 mAb did not inhibit benzene metabolism, whereasclone 2-66-3 inhibited only in PB-induced microsomes at a highconcentration of benzene (6.26 mM), and clone 1-91-3 mAb inhibitedbenzene metabolism in all cases. The degree of inhibition wasas follows: fed isocaloric control PB < fasted < pyrazole ethanol. The pattern of inhibition was similar with clone 1-91-3for low (0.23 mM) and high concentrations of benzene, exceptin PB-induced mkrosomes. Western blot analysis showed that clone1-7-1 mAb did not bind any liver mkrosomal protein in the regionof cytochrome P-450s, whereas with clone 2-66-3 a clear-cutband was seen only in liver microsomes from PB-treated rats,with clone 1-98-1, a band was detected in mkrosomes from alltreated groups, in the following order: PB = isocaloric control< fed < fasted < pyrazole < ethanol. These resultsindicate that (i) cytochromes P-450b,e and P-450J contributeto benzene metabolism in rat liver; (ii) the former has a lowaffinity to benzene and is induced by PB; and (iii) P-450J hasa high affinity to benzene and is induced by 1-day fasting,pyrazole and ethanol, but decreased by PB treatment.  相似文献   
4.
BACKGROUND AND AIMS: Poor vision in older people is often related to increased fall risk. However, the association of the severity between visual deficit and risk for all kind of injurious accidents has not been widely studied. The aim of this study was to examine whether visual loss is associated with higher incidence of injurious accidents and whether walking speed or physical activity play a mediating role in the association. METHODS: 416 persons aged 75 and 80 years at baseline underwent visual acuity measurements. Visual acuity (VA) <0.3 in the better eye, with spectacle correction when necessary, was defined as visual impairment, VA >or=0.3 but 0.5 as normal VA. Hospital records of accidents resulting in injury were monitored for 10 years after baseline. RESULTS: During the 10-year follow-up, 239 (58%) participants suffered at least one injurious accident. The risk for injurious accidents in a multivariate model adjusted for age, gender, eye-related diseases, diabetes and cardiovascular diseases among participants with lowered vision was 1.45 (95% CI 1.08- 1.94), compared with that for people with normal visual acuity. Participants with visual impairment did not have an increased risk for injurious accidents (HR 1.20, 95% CI 0.82-1.75). Furthermore, neither walking speed nor physical activity had a mediating effect on the relationship between visual loss and accidents. CONCLUSIONS: Lowered vision is a risk factor for injurious accidents in older people independent of mobility and physical activity. Interestingly, more severe visual impairment did not increase the risk. Early intervention strategies, for example, proper correction of refractive errors or cataract extraction, may potentially prevent injurious accidents in older people.  相似文献   
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6.
Socio-economic differences in self-reported disability are well described but much less is known about their associations with more objective measures of physical capacity. The aim was to study socio-economic differences in performance-based physical capacity in 75-year-old persons, examining changes in performance at five- and ten-year follow-up intervals. At the baseline 350 residents of the city of Jyv?skyl?, Finland, aged 75 were interviewed and 295 of them took part in clinical examinations. The corresponding figures at the five-year follow-up were 234 and 191 and at the ten-year follow-up 139 and 103. The statistical significance of differences in physical capacity between the socio-economic groups and genders were tested using ANOVA in univariate and repeated measures models and ANCOVA, with confounders added to the models. Generally, higher education and income were separately related to better maximal walking speed and vital capacity at every measurement point. In addition, higher income was related to better maximal isometric hand grip strength at both follow-ups. When education and income were in the same model, only income was related to physical capacity, almost without exception. Similarly, in the five- and ten-year follow-up periods, both education and income groups showed a parallel decline in physical capacity. The association between income and physical capacity remained even after adjusting for smoking, physical activity and number of chronic diseases. The results indicate that elderly people in disadvantaged socio-economic groups show lower levels of performance in almost all domains of physical capacity, but change in capacity over time does not differ significantly between either markers of socio-economic position.  相似文献   
7.
Abstract The importance of sugar in the etiology of dental caries is well known but only few representative studies at population level have been carried out to analyze nutritional factors related to dentistry. As the main exposure to caries the frequency of the use of sugar-products should be known more exactly than we do. The purpose of this study was to analyze the frequency of consumption of sugar-containing products among Finnish adolescents. A representative sample of 3209 Finnish adolescents between the ages of 13 and 19 was drawn. The data were obtained by mail questionnaire in February and September 1977, and in February and September 1979. The separate sample was drawn in February 1978 to analyze the changes with time during 1977–79. The response rate to all the mailed questionnaires was close to 90%. The sugar-containing foods included in the study were sugar in codec or tea, hot chocolate, pastries and cookies, soft drinks, chewing gums, sweets and pastilles. In addition, the data on the consumption of artificial sweeteners were collected. According to current health behavior dogma, girls behaved better than boys. A clear relationship was observed between a householder's educational and occupational status and the children's sugar consumption. Children from homes of low social status consumed more sugar than the others. The percentage of children frequently consuming sugary products decreased with improved school success. It can be concluded that the use of sugar-containing products is especially frequent among young age groups, particularly among boys from low social background and children with poor school success. Health education should be especially directed towards them.  相似文献   
8.
Secretory Otitis Media and Allergy   总被引:1,自引:1,他引:0  
Jorma  Ruokonen  Eino  Holopainen  Tauno  Palva Alf  Backman 《Allergy》1981,36(1):59-68
This study is an investigation on whether allergy, and especially food allergy, is more common in patients with secretory otitis media (SOM) than in others. At the same time, the effectiveness of the cytotoxic leucocyte test (CLT) as an aid in the diagnosis of food allergy was also studied. The material comprised 90 patients: 69 suffering from secretory otitis media and 21 without the disease as controls. Patients were studied using allergy history, ear status, tests for nasal and blood eosinophilic cells, total IgE, skin tests for 20 allergens, RAST for milk and wheat, immunoglobulin A, G and M, precipitating antibodies for milk and gluten, Mantoux test, and the CLT for 23 allergens. Allergy was found in 20% of the SOM patients and 10% of the control patients; the difference was not statistically significant. The best methods for verifying allergy were history, skin tests, and tests for nasal eosinophilic cells. Laborartory tests could not verify objectively that food allergy was more common among SOM patients than controls, although 16% of the SOM patients compared with none of the controls had a history of food allergy. Of the tests used, the CLT correlated best with a history of allergy, but the results of the different tests were not in accordance with each other.  相似文献   
9.
PURPOSE: This study examined the relative contribution of genetic and environmental effects on maximal leg extensor power and also investigated whether leg extensor power and maximum voluntary isometric knee extensor strength share a genetic component. METHODS: Muscle functions were measured as part of the Finnish Twin Study on Aging in 101 monozygotic (MZ) and 116 dizygotic (DZ) female twin pairs aged 63-76 yr. Leg extensor power was measured using the Nottingham Leg Extensor Power Rig and maximum voluntary isometric knee extensor strength using an adjustable dynamometer chair. The analyses were carried out using the maximum likelihood method in Mx-program on the raw data set. RESULTS: A bivariate Cholesky decomposition model showed that leg extensor power and isometric knee extensor strength shared a genetic component in common, which accounted for 32% of the total variance in leg extensor power and 48% in isometric knee extensor strength. In addition, power and strength had a nonshared environmental effect in common accounting for four percent of the variance in power and 52% in strength. Remaining variance for leg extensor power was due to trait-specific shared and nonshared environmental effects. CONCLUSION: Observed genetic effect in common for leg extensor power and maximum voluntary isometric knee extensor strength indicated that these two traits are regulated by the same genes. However, also environmental effects have a significant role in explaining the variability in power and strength.  相似文献   
10.
Open in a separate window OBJECTIVESTracheobronchial stenting has an established role in the palliation of malignant central airway obstruction (CAO). The purpose of this study is to describe the experience with self-expanding metal airway stents in 2 tertiary referral centres, covering a third of the population of Finland.METHODSPatients referred to and treated with airway stenting for malignant CAO using self-expanding metal-stents were identified from electronic patient records, and data were collected using a structured Endoscopic Lower Airway Management instrument. Statistical analysis to reveal factors affecting patient benefit and survival was carried out.RESULTSA total of 101 patients (mean age 65.8) and 116 procedures were identified. Procedure-related mortality was rare (3/101 patients) and complications infrequent. The median survival was 2.3 months [95% confidence interval (CI): 1.4–3.1). Stent benefit was not significantly affected by clinical characteristics. Survival was impacted by the use of adjunct procedures [hazard ratio (HR) 0.36, 95% CI: 0.23–0.58, P < 0.001), procedural urgency (HR 0.40; 95% CI: 0.23–0.71, P = 0.002) and post-treatment chemoradiotherapy (HR 0.29, 95% CI: 0.15–0.56, P < 0.001).CONCLUSIONSThe beneficial impact observed supports the further use of tracheobronchial stenting in malignant CAO. The use of self-expanding metal stents is encouraged.  相似文献   
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