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1.
ObjectiveTo evaluate the effect of a smoking ban in high schools on smoking behaviour among Chilean students.MethodsWe conducted an interrupted time-series analysis, using repeated cross-sectional data from Chile’s school population survey (2000–2011) for high-school students aged 12–18 years and a control group of persons aged 19–24 years. Poisson regression models were used to assess trends in smoking behaviour before and after the policy changes. The outcome measures were self-reported smoking prevalence (any smoking in the past month) and high frequency of smoking (smoking 15 days or more per month).FindingsFrom 2005 to 2011, the prevalence of smoking declined among high-school students by 6.8% per year compared with 3.6% decline per year in the control group. The decline in the target group was 2.9% (95% confidence interval, CI: 0.18 to 5.00) greater. We estimated that 5–6 years after enforcing the law, smoking prevalence among high-school students was 13.7% lower as a result of the ban. The impact of the smoking ban was primarily driven by declines in smoking prevalence among students in grades 8 to 10. The smoking ban did not significantly alter the frequency of smoking.ConclusionThe 2005 school smoking ban reduced smoking prevalence among younger high-school students in Chile. Further interventions targeting older individuals and frequent smokers may be needed.  相似文献   
2.

Background

Cardiovascular prognostic models guide treatment allocation and support clinical decisions. Whether there are valid models for Latin American and Caribbean (LAC) populations is unknown.

Objective

This study sought to identify and critically appraise cardiovascular prognostic models developed, tested, or recalibrated in LAC populations.

Methods

The systematic review followed the CHARMS (CHecklist for critical Appraisal and data extraction for systematic Reviews of prediction Modelling Studies) framework (PROSPERO [International Prospective Register of Systemic Reviews]: CRD42018096553). Reports were included if they followed a prospective design and presented a multivariable prognostic model; reports were excluded if they studied symptomatic individuals or patients. The following search engines were used: EMBASE, MEDLINE, Scopus, SciELO, and LILACS. Risk of bias assessment was conducted with PROBAST (Prediction model Risk Of Bias ASsessment Tool). No quantitative summary was conducted due to large heterogeneity.

Results

From 2,506 search results, 8 studies (N = 130,482 participants) were included for qualitative synthesis. We could not identify any cardiovascular prognostic model developed for LAC populations; reviewed reports evaluated available models or conducted a recalibration analysis. Only 1 study included a Caribbean population (Puerto Rico); 3 studies were retrieved from Chile; 2 from Argentina, Brazil, Colombia, and Uruguay; and 1 from Mexico. Four studies included population-based samples, and the other 4 included people affiliated to a health facility (e.g., prevention clinics). Most studied participants were older than 50 years, and there were more women in 5 reports. The Framingham model was assessed 6 times, and the American College of Cardiology/American Heart Association pooled equation was assessed twice. Across the prognostic models assessed, calibration varied widely from one population to another, showing great overestimation particularly in some subgroups (e.g., highest risk). Discrimination (e.g., C-statistic) was acceptable for most models; for Framingham it ranged from 0.66 to 0.76. The American College of Cardiology/American Heart Association pooled equation showed the best discrimination (0.78). That there were few outcome events was the most important methodological limitation of the identified studies.

Conclusions

No cardiovascular prognostic models have been developed in LAC, hampering key evidence to inform public health and clinical practice. Validation studies need to improve methodological issues.  相似文献   
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Remarkable findings from genome-wide association studies (GWAS) on blood pressure (BP) traits have made new insights for developing precision medicine toward more effective screening measures. However, generality of GWAS findings in diverse populations is hampered by some technical limitations. There is no comprehensive study to evaluate source(s) of the non-generality of GWAS results on BP traits, so to fill the gap, this systematic review study was carried out. Using MeSH terms, 1545 records were detected through searching in five databases and 49 relevant full-text articles were included in our review. Overall, 749 unique variants were reported, of those, majority of variants have been detected in Europeans and were associated to systolic and diastolic BP traits. Frequency of genetic variants with same position was low in European and non-European populations (n = 38). However, more than 200 (>25%) single nucleotide polymorphisms were found on same loci or linkage disequilibrium blocks (r2 ≥ 80%). Investigating for locus position and linkage disequilibrium of infrequent unique variants showed modest to high reproducibility of findings in Europeans that in some extent was generalizable in other populations. Beyond theoretical limitations, our study addressed other possible sources of non-generality of GWAS findings for BP traits in the same and different origins.  相似文献   
5.

Background

Overweight and obesity prevalence are commonly used for public and policy communication of the extent of the obesity epidemic, yet comparable estimates of trends in overweight and obesity prevalence by country are not available.

Methods

We estimated trends between 1980 and 2008 in overweight and obesity prevalence and their uncertainty for adults 20 years of age and older in 199 countries and territories. Data were from a previous study, which used a Bayesian hierarchical model to estimate mean body mass index (BMI) based on published and unpublished health examination surveys and epidemiologic studies. Here, we used the estimated mean BMIs in a regression model to predict overweight and obesity prevalence by age, country, year, and sex. The uncertainty of the estimates included both those of the Bayesian hierarchical model and the uncertainty due to cross-walking from mean BMI to overweight and obesity prevalence.

Results

The global age-standardized prevalence of obesity nearly doubled from 6.4% (95% uncertainty interval 5.7-7.2%) in 1980 to 12.0% (11.5-12.5%) in 2008. Half of this rise occurred in the 20 years between 1980 and 2000, and half occurred in the 8 years between 2000 and 2008. The age-standardized prevalence of overweight increased from 24.6% (22.7-26.7%) to 34.4% (33.2-35.5%) during the same 28-year period. In 2008, female obesity prevalence ranged from 1.4% (0.7-2.2%) in Bangladesh and 1.5% (0.9-2.4%) in Madagascar to 70.4% (61.9-78.9%) in Tonga and 74.8% (66.7-82.1%) in Nauru. Male obesity was below 1% in Bangladesh, Democratic Republic of the Congo, and Ethiopia, and was highest in Cook Islands (60.1%, 52.6-67.6%) and Nauru (67.9%, 60.5-75.0%).

Conclusions

Globally, the prevalence of overweight and obesity has increased since 1980, and the increase has accelerated. Although obesity increased in most countries, levels and trends varied substantially. These data on trends in overweight and obesity may be used to set targets for obesity prevalence as requested at the United Nations high-level meeting on Prevention and Control of NCDs.
  相似文献   
6.
Numerical simulations have been carried out on a model of the right passageway of an anonymous, adult male's nasal cavity, constructed from magnetic resonance imagery (MRI) scans. Steady, laminar, inspiratory flow was assumed to simulate inhalation. Analysis shows smoothly varying streamlines with a peak in velocity magnitude occurring in the nasal valves and a peak in vorticity magnitude immediately posterior. Dilute, uniform concentrations of inertial (1 microm < or = d(ae) < or = 10 microm) particles were released at the nostril and tracked via a Lagrangian tracking algorithm. Deposition efficiency is shown to increase with particle size and flow rate. Preferential deposition is seen in the anterior third of the nasal cavity for large Stokes number particles. An empirical expression for particle deposition is proposed that incorporates particle size, flow rate, and nose anatomy.  相似文献   
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Solidago virgaurea (goldenrod) has traditionally been used as an anti-inflammatory herbal medicine for the treatment of various symptoms, including prostatic diseases. The plant has also been reported to have antibacterial, spasmolytic, and carminative properties. During the course of our screening for antineoplastic activities in various herbal plants, we found that the extract of S. virgaurea exhibits strong cytotoxic activities on various tumor cell lines. The active component mostly resides in the leaves of the plant and is soluble in water. When the extract was fractionated by a Sephadex G-100 column, the active fraction corresponded to a molecular weight of approximately 40,000. This cytotoxic activity is effective on various tumor cell lines, including human prostate (PC3), breast (MDA435), melanoma (C8161), and small cell lung carcinoma (H520). To examine the effect of the cytotoxic activity on tumor cells in vivo, we used the rat prostate cell line (AT6.1) and an SCID mouse model. AT6.1 cells were injected into the flank of SCID mice, and then the G-100 fraction of S. virgaurea was administered intraperitoneally or subcutaneously every 3 days. The size of the tumor was measured for up to 25 days. The growth of the tumor was significantly suppressed by the G-100 fraction at 5 mg/kg without any apparent side effects. Therefore, S. virgaurea is considered to be promising as an antineoplastic medicine with minimal toxicities.  相似文献   
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Nutrition‐sensitive interventions to improve overall diet quality are increasingly needed to improve maternal and child health. This study demonstrates feasibility of a structured process to leverage local expertise in formulating programmes tailored for current circumstances in South Asia and Africa. We assembled 41 stakeholders in 2 regional workshops and followed a prespecified protocol to elicit programme designs listing the human and other resources required, the intervention's mechanism for impact on diets, target foods and nutrients, target populations, and contact information for partners needed to implement the desired programme. Via this protocol, participants described 48 distinct interventions, which we then compared against international recommendations and global goals. Local stakeholders' priorities focused on postharvest food systems to improve access to nutrient‐dense products (75% of the 48 programmes) and on production of animal sourced foods (58%), as well as education and social marketing (23%) and direct transfers to meet food needs (12.5%). Each programme included an average of 3.2 distinct elements aligned with those recommended by United Nations system agencies in the Framework for Action produced by the Second International Conference on Nutrition in 2014 and the Compendium of Actions for Nutrition developed for the Renewed Efforts Against Child Hunger initiative in 2016. Our results demonstrate that a participatory process can help local experts identify their own priorities for future investments, as a first step in a novel process of rigorous, transparent, and independent priority setting to improve diets among those at greatest risk of undernutrition.  相似文献   
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