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51.
Specific coping mechanisms of Africans during urbanization were compared to and correlated with cardiovascular responses and perception of health data. Subjects included men (N=286) and women (N=360). The COPE questionnaire classified subjects as active (AC) or passive (PC) copers and the General Health Questionnaire measured subjective perception of health. The Finapres recorded blood pressure continuously before and during application of a handgrip test. Analyses adjusting for age, body mass index and resting cardiovascular data revealed that AC rural subjects showed predominantly cardiac responses and PC rural subjects predominantly vascular responses. All urbanized African men and women showed higher resting blood pressure, vascular responsiveness and hypertension prevalences than their rural counterparts. All rural AC subjects, especially women, and all urban PC subjects, especially men, reported a poorer perception of health. In conclusion, subjects with a PC style showed a predominantly vascular response in rural and urban areas whereas subjects with an AC style seem to shift from a predominant cardiac output response to a predominant vascular resistance response when moving from a rural to an urban area.  相似文献   
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BACKGROUND: Psychopathological rating scales are developed and tested on a relatively young population. Their applicability and psychometric performance in the elderly (aged above 60-65 years) are mostly unknown. It is unknown how factors related to ageing or mild cognitive dysfunction influence the applicability and the reliability of these scales. We tested the applicability and the inter-rater reliability of the Dutch version of the Comprehensive Psychopathological Rating Scale (CPRS) on an elderly (age > 60 years) inpatient population. METHODS: The applicability and reliability (expressed by differently weighted Kappa coefficients) of the CPRS was assessed by investigating 62 consecutively referred patients in a ward for elderly patients with acute psychiatric problems that were primarily functional in nature. The results are compared with those found in a younger population. RESULTS: The applicability and reliability of the CPRS on the elderly can be categorised as sufficient to good and is comparable with results for a younger population. We did not find any specific factors influencing the practicality, or the reliability of the CPRS when applied to an elderly group of people with a mild cognitive dysfunction. CONCLUSIONS: The CPRS does not loose its clinical relevance with age, as the applicability and the reliability of the CPRS is not influenced by ageing or mild cognitive dysfunction. The CPRS can detect a broad range of symptoms and due to its psychometric properties it is a useful instrument for measuring an elderly or young population.  相似文献   
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OBJECTIVE: As alkaline phosphatase may play a role in cell differentiation, our aim was to study the possible role of this enzyme in the differentiation of preadipocytes (3T3-L1 cells) into adipocytes. RESEARCH METHODS AND PROCEDURES: 3T3-L1 cells were grown in medium containing insulin, dexamethasone and IBMX to induce adipogenesis. Adipogenesis was measured using the triglyceride-specific dye, oil red O at 0, 3, 7 and 11 days after initiation of adipogenesis in the presence or absence of the alkaline phosphatase inhibitors, levamisole, histidine and Phe-Gly-Gly. Intracellular localisation of the enzyme was detected using ELF-phosphatase, a fluorescent substrate and alkaline phosphatase gene expression was assessed using RT-PCR. RESULTS: Alkaline phosphatase activity was detected in untransformed cells (1.91+/-0.62 mU/mg protein) and activity increased 11.5+/-1.4-fold after 11 days treatment with transformation medium and 5.3+/-0.3-fold in transformation medium containing levamisole (p<0.05). Triglyceride content of cells increased 3.1+/-0.2-fold after 11 days treatment with transformation medium and 2.1+/-0.3-fold in the presence of levamisole (p<0.005). Histidine inhibited adipogenesis and alkaline phosphatase to a greater extent than did levamisole, but Phe-Gly-Gly had no effect on these variables. Alkaline phosphatase was localised around the lipid droplets of the cells. Gene expression of alkaline phosphatase increased during adipogenesis. DISCUSSION: This study demonstrates that tissue-nonspecific alkaline phosphatase is present in 3T3-L1 cells and that it may play a role in the control of adipogenesis.  相似文献   
54.
BACKGROUND: The Finometer (FMS, Finapres Measurement Systems, Arnhem, Netherlands), which is the improved successor of the Finapres (TNO Biomedical Instrumentation, Amsterdam, Netherlands), measures finger arterial blood pressure non-invasively and computes other cardiovascular parameters from the computed aortic-flow waveform. The usability of the Finometer would depend on whether it is sensitive enough to detect small cardiovascular changes. The aim was therefore to determine the sensitivity of the Finometer regarding acute and longer-term cardiovascular changes. DESIGN AND METHODS: The sensitivity of the Finometer regarding the acute effect of 200 mg caffeine was determined with a double-blind, placebo-controlled crossover study which included 38 young male subjects. Finometer recordings were performed during four occasions at fasting level and after 30 min of ingestion. To evaluate the sensitivity of the Finometer in recording longer-term effects of a daily dosage of 1000 mg vitamin C, 800 mg vitamin E and 10 mg folic acid, 14 young males took placebo and 17 took the vitamins for 12 weeks in a double-blind study. Two recordings were performed at baseline and two after 12 weeks. RESULTS: After caffeine ingestion significantly (P<0.05) higher systolic, diastolic and mean blood pressure values than resting values were obtained. The arterial compliance was significantly lower after caffeine ingestion, whereas heart rate, peripheral resistance, stroke volume and cardiac output did not change significantly. No differences were shown after intake of placebo. Concerning the effects of vitamin intake, the vitamin group indicated a significant decrease in systolic blood pressure (P=0.03) whereas the placebo group indicated no significant differences after 12 weeks. CONCLUSIONS: The results suggest that the improved Finometer might be a sensitive instrument in the recording of relative small acute and longer-term changes in cardiovascular function, but more studies are necessary before final conclusions can be drawn.  相似文献   
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The purpose of this study was to compare active and passive coping strategies of Africans with perception of own health and cardiovascular data. The subjects included 236 apparently healthy Africans (men=109; women=127). The COPE questionnaire was adapted, translated and validated for Africans. Scores on reliable sub-scales were used to classify men and women into more active coping (AC) and more passive coping (PC) subgroups. The General Health Questionnaire measured subjective perception of health. Blood pressure was recorded before and during application of the handgrip test, using the Finapres, a continuous non-invasive blood pressure monitor. Plasma renin activity (PRA) values, measured with radio immuno assay, were compared to blood pressure variables. Analyses of co-variance, adjusted for resting values and age, indicated that PC men responded with a larger increase in total peripheral resistance (TPR) (p=0.006), larger decrease in stroke volume (p=0.07), smaller increase in cardiac output (p=0.09) and larger increases in PRA resting (p=0.04) and reactivity (p< or =0.05) values. PC subjects reported a more negative perception of health than AC subjects. Young PC women presented greater hypertension prevalence rates (p< or =0.01) than AC women. In conclusion, all AC and PC subjects reacted with increased vascular reactivity on the handgrip test. PC men presented enhanced vascular reactivity, PRA and perception of poorer health values.  相似文献   
56.
OBJECTIVE: Early changes in vascular function could be associated with stunting, which may contribute to the development of cardiovascular diseases in later life. In this study we tested the hypothesis that stunting may be related to changes in cardiovascular function in African children ages 10 to 15 y. METHODS: In the Transition and Health during Urbanization in South Africa in Children study, the health status of children in the North-West Province of South Africa was studied. It was an epidemiologic, cross-sectional study in which 583 black non-stunted and 192 stunted children (stature below the fifth percentile for age) of both sexes ages 10 to 15 y were recruited from 44 schools. Blood pressure was monitored with the Finapres (finger-arterial pressure) apparatus and by means of the Fast Modelflo software program; measurements for systolic and diastolic blood pressure, mean arterial pressure, pulse pressure, heart rate, cardiac output, stroke volume, total peripheral resistance, and arterial compliance were obtained. Dietary intake data were collected with a 24-h dietary recall questionnaire. Nutrient coding was the same for all recalls and macro- and micronutrients were calculated. Anthropometric measurements were done according to standard methods. RESULTS: There were no significant differences in systolic blood pressure and diastolic blood pressure between stunted and non-stunted children after correction for body mass index and heart rate. Stroke volume, arterial compliance, and cardiac output were significantly lower and total peripheral resistance was significantly higher in stunted children than in non-stunted children. No significant differences in dietary intake could be detected, although dietary intakes were slightly lower in the stunted children. CONCLUSIONS: We found that compliance, a marker of vascular function, is significantly lower in stunted children. Stunting was related to early changes in cardiovascular function in African children ages 10 to 15 y.  相似文献   
57.
There is increasing evidence that inflammatory mechanisms other than atopy or eosinophilic inflammation may be involved in the pathogenesis of asthma. The mechanisms associated with non-atopic (non-IgE) or neutrophil-mediated asthma are poorly investigated. Non-atopic airway inflammation and hyperresponsiveness was induced in mice by skin sensitization with dinitrofluorobenzene (DNFB) followed by intra-airway challenge with dinitrobenzene sulfonic acid (DNS). Acute bronchoconstriction and mast cell activation were observed shortly after challenge. Increased levels of the major mast cell mediator, TNF-alpha, were found in the bronchoalveolar lavage fluid of DNFB-sensitized. Mast cells play a key role in the early release of TNF-alpha since mast-cell-deficient WBB6F1-W/Wv mice did not show an increase in TNF-alpha release after DNFB-sensitization and DNS challenge compared to their ++ littermates. Features of the late-phase pulmonary reaction included mononuclear and neutrophilic cell infiltration, pulmonary edema, in vitro tracheal hyperreactivity and in vivo airway hyperresponsiveness. These characteristics bear marked similarity with those observed in non-atopic asthmatic patients. Therefore, this model can be used to further study the mechanisms potentially responsible for the development of non-IgE-mediated asthma.  相似文献   
58.
Background and aimsObesity is associated with an increasing prevalence of cardiovascular diseases in Africa, but some obese individuals maintain cardiometabolic health. The aims were to track metabolically healthy overweight or obesity (MHO) over 10 years in African adults and to identify factors associated with a transition to metabolically unhealthy overweight or obesity (MUO).Methods and resultsThe participants were the South African cohort of the international Prospective Urban and Rural Epidemiological study. From the baseline data of 1937 adults, 649 women and 274 men were followed for 10 years. The combined overweight and obesity prevalence of men (19.2%–23.8%, p = .02) and women (58%–64.7%, p < .001), and the prevalence of the metabolic syndrome in all participants (25.4%–40.2%, p < .001) increased significantly. More than a quarter (26.2%) of the women and 10.9% of men were MHO at baseline, 11.4% of women and 5.1% of men maintained MHO over 10 years, while similar proportions (12.3% of women, 4.7% of men) transitioned to MUO. Female sex, age, and total fat intake were positively associated with a transition to MUO over 10 years, while physical activity was negatively associated with the transition. HIV positive participants were more likely to be MHO at follow-up than their HIV negative counterparts.ConclusionsOne in two black adults with BMI ≥25 kg/m2 maintained MHO over 10 years, while a similar proportion transitioned into MUO. Interventions should focus on lower fat intakes and higher physical activity to prevent the transition to MUO.  相似文献   
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