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1.
The objective of the study was to evaluate the fluoride concentration in bottled water available on the market, in comparison with the values printed on the bottle label. Two hundred and twenty-nine water samples were collected from 35 brands available in several supermarkets, grocery stores and snack bars with high turnover in different regions of the municipality of S?o Paulo, Southeastern Brazil, in 2006. Fluoride concentrations were determined by duplicate analysis using an ion-specific electrode. The fluoride concentrations ranged from 0.01 to 2.04 mg/l, with significant differences between the values stipulated on labels and those found in the analyses. These results emphasize the importance of controls over fluoride levels in bottled water enforced by the sanitary surveillance agency.  相似文献   

2.
Objectives: To ensure safety and health the avoidance of adverse chemosensory effects is essential at workplaces where volatile chemicals are used. The present study describes psychophysical approaches that provide information for the evaluation of such effects. Methods: By means of a modified staircase procedure the odor (OT) and irritation thresholds (IT) of 15 irritants were determined. These basic chemosensory properties, confining the chemosensory effect range, were investigated in a random sample of 144 persons stratified for gender and age. Those irritants exhibiting high chemosensory potency were selected for the second psychophysical part of the study. Forty-eight persons, again stratified for gender and age, rated the intensity of 13 trigeminal and olfactory perceptions elicited by nine ascending concentrations of the irritants, ranging from the odor to the irritation threshold of the respective substances. Results: Across the investigated chemicals the transition from concentrations eliciting pure olfactory stimulation (OT) to trigeminal stimulation (IT) differed markedly. The carboxylic acids yielded narrow ranges from odor to irritation thresholds, while for the amines (cyclohexylamine, dimethylamine, and trimethylamine) and the esters (ethyl formate and ethyl acetate) these ranges were somewhat wider. The two chemosensory thresholds of ethyl acrylate and ammonia were farthest from each other. Gender and age had only weak impact on the chemosensory thresholds. At present, the results of the intensity ratings could be given for six substances. Among them, the rated pungency for cyclohexylamine, formic acid, and ethyl acetate increased strongest across the nine applied concentrations. Conclusions: By means of these psychophysical approaches a diverse class of chemicals can be described and compared with respect to their chemosensory potency. This information can be used twofold (a) for the evaluation of existing studies reporting sensory irritations and (b) for the design of experimental exposure studies.  相似文献   

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The purpose of this study was to analyze studies that tested the effects of childbirth education on the parent‐infant relationship. Using meta‐analysis techniques, published and unpublished childbirth education research literature from 1960 to 1981 was analyzed. From the analysis of 27 studies, it was found that childbirth education is beneficial to the parent‐infant relationship. A greater magnitude of effect was found for middle income parents, as compared to parents with low income. Moderate effects were found in both the behavioral and attitudinal components of die parent‐infant relationship. Several methodologic flaws in the research were found. Many researchers either demonstrated allegiance to childbirth education, conducted the research while knowledgeable of the composition of the groups or taught the classes, or used instruments without reliability or validity testing. Recommendations for future childbirth education research, relating to the philosophical foundation of research, the foci of study, and methodologic considerations, have been made.  相似文献   

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In the notification procedure for new substances, the need to conduct further toxicity tests may arise if the outcome of a qualitative or quantitative risk assessment indicates relevant risks. Sometimes a quantitative assessment is not possible (e.g., if a no observed adverse effect level [NOAEL] is not available). A different approach is required for such substances. An approach based on the correlation of the classification of the substance (the possible outcome of testing) with the assumed tolerable exposure levels is presented here. It relates to the hazard band model developed by the Health and Safety Executive (HSE) of the United Kingdom. To aid decision-making, the assumed tolerable exposure level is compared with the estimated workplace exposure level by means of calculating the quotient of these two figures. The quotient is called the assumed margin of safety (AMOS). A quotient higher than 1 means that testing may be deferred. The approach is described for a powdery substance used as a pigment in the coloration of plastics and rubber. Depending on the exposure situation, the need for further testing to determine the repeated dose toxicity of the substance is discussed.  相似文献   

7.
《Alcohol》1995,12(6):531-534
Recent findings suggest that a genetic deficit in opioids may be a biological marker of alcoholism. In other words, decreased plasma concentrations of opioids may be a predisposing factor, rather than a consequence, of alcohol consumption. We attempted to classify 88 randomly chosen individuals as alcoholics or nonalcoholics on the basis of plasma concentration of β-endorphins. This criterion had a sensitivity of 73.30% and a specificity of 79.45%. Its positive predictive value was 42.30%, and its negative predictive value was 93.55%.  相似文献   

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Simulation games are becoming increasingly popular in education, but more insight in their critical design features is needed. This study investigated the effects of fidelity of open patient cases in adjunct to an instructional e-module on students’ cognitive skills and motivation. We set up a three-group randomized post-test-only design: a control group working on an e-module; a cases group, combining the e-module with low-fidelity text-based patient cases, and a game group, combining the e-module with a high-fidelity simulation game with the same cases. Participants completed questionnaires on cognitive load and motivation. After a 4-week study period, blinded assessors rated students’ cognitive emergency care skills in two mannequin-based scenarios. In total 61 students participated and were assessed; 16 control group students, 20 cases students and 25 game students. Learning time was 2 h longer for the cases and game groups than for the control group. Acquired cognitive skills did not differ between groups. The game group experienced higher intrinsic and germane cognitive load than the cases group (p = 0.03 and 0.01) and felt more engaged (p < 0.001). Students did not profit from working on open cases (in adjunct to an e-module), which nonetheless challenged them to study longer. The e-module appeared to be very effective, while the high-fidelity game, although engaging, probably distracted students and impeded learning. Medical educators designing motivating and effective skills training for novices should align case complexity and fidelity with students’ proficiency level. The relation between case-fidelity, motivation and skills development is an important field for further study.  相似文献   

10.
Heat waves in Madrid 1986–1997: effects on the health of the elderly   总被引:5,自引:0,他引:5  
OBJECTIVE: The objective of this paper is to analyse and quantify the effects exerted on summer mortality by extremes of heat, particularly among persons aged 65-74 and 75 years and over, groups in which mortality is higher. METHODS: The study included the period from 1 January 1986 to 31 December 1997, for all people aged over 65 years resident in Madrid, based on mortality due to all causes except accidents (ICD-9 codes 1-799), and circulatory (390-459) and respiratory (460-487) causes. Meteorological variables analysed were: daily maximum temperature, daily minimum temperature and relative humidity. To control the effect of air pollution on mortality we considered the daily mean values of sulphur dioxide (SO2), total suspended particulate (TSP), nitric oxides (NOx), nitrogen dioxide (NO2) and tropospheric ozone (O3). Univariate and multivariate ARIMA models were used. Box-Jenkins pre-whitening was performed. RESULTS: The results yielded by this study indicate a mortality increase up to 28.4% for every degree the temperature rises above 36.5 degrees C, with particular effect in women over the age of 75 years and circulatory-cause mortality. The first heat wave that leads to the greatest effects on mortality, due to the higher number of susceptible people and the duration of the heat wave, show an exponential growth in mortality. Furthermore, low relative humidity enhances the effects of high temperature, linking dryness to air pollutants, ozone in particular. CONCLUSIONS: Since a warmer climate is predicted in the future, the incidence of heat wave should increase, and more comprehensive measures, both medical and social, should be adopted to prevent the effects of extreme heat on the population, particularly the elderly.  相似文献   

11.
Survey results of a nationwide sample frame did not differ from those of a statewide sample frame with respect to questions that were professional/procedural in nature or that dealt with putative industry knowledge. However, on questions that were attitudinal in nature, the sample frames differed significantly. Because of this, the authors conclude that using a geographically narrow convenience sample may or may not result in frame error, depending on the information being sought.  相似文献   

12.

Background

Reduced opportunities for children’s schooling and spouse’s/partner’s employment are identified internationally as key barriers to general practitioners (GPs) working rurally. This paper aims to measure longitudinal associations between the rurality of GP work location and having (i) school-aged children and (ii) a spouse/partner in the workforce.

Methods

Participants included 4377 GPs responding to at least two consecutive annual surveys of the Medicine in Australia: Balancing Employment and Life (MABEL) national longitudinal study between 2008 and 2014. The main outcome, GP work location, was categorised by remoteness and population size. Five sequential binary school-age groupings were defined according to whether a GP had no children, only preschool children (aged 0–4 years), at least one primary-school child (aged 5–11 years), at least one child in secondary school (aged 12–18 years), and all children older than secondary school (aged ≥?19). Partner in the workforce was defined by whether a GP had a partner who was either currently working or looking for work, or not. Separate generalised estimating equation models, which aggregated consecutive annual observations per GP, tested associations between work location and (i) educational stages and (ii) partner employment, after adjusting for key covariates.

Results

Male GPs with children in secondary school were significantly less likely to work rurally (inclusive of >?50 000 regional centres through to the smallest rural towns of <?5000) compared to male GPs with children in primary school. In contrast, female GPs’ locations were not significantly associated with the educational stage of their children. Having a partner in the workforce was not associated with work location for male GPs, whereas female GPs with a partner in the workforce were significantly less likely to work in smaller rural/remote communities (<?15 000 population).

Conclusions

This is the first systematic, national-level longitudinal study showing that GP work location is related to key family needs which differ according to GP gender and educational stages of children. Such non-professional factors are likely to be dynamic across the GP’s lifespan and should be regularly reviewed as part of GP retention planning. This research supports investment in regional development for strong local secondary school and partner employment opportunities.
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Nonalcoholic fatty liver disease (NAFLD) is the most common liver disease and its incidence is rising worldwide. We compared the antioxidant capacity of seventeen flavonoids with their inhibitory effects on oleic acid-induced triglyceride (TG) over-accumulation in HepG2 cells. The results showed significant correlations (P < 0.01) between the inhibition of intracellular TG levels and the suppression effects on reactive oxygen species. Nevertheless, the radical-reducing activities of flavonoids assessed by chemical assays (cyclic voltammetry and Folin-Ciocalteu reagent assay) were poorly correlated with their intracellular TG inhibitory effects. The relationships between structural properties of flavonoids and their inhibitory effects on TG over-accumulation were discussed.  相似文献   

15.
El Niño effects on influenza mortality risks in the state of California   总被引:2,自引:0,他引:2  
Recent El Ni?o events have emphasized the need to develop modelling techniques to assess climate-related health events. Experts agree that climate changes affect the spread of infectious diseases and that the geographic range of infectious diseases may expand as a result of these changes. Nevertheless, the world health modelling community cannot yet predict, with reasonable accuracy, when or where exactly these effects will occur or how large the threat of these diseases will be to particular populations. This study compared the spatiotemporal patterns of influenza mortality risk in the state of California during El Ni?o vs normal weather periods. By applying a stochastic methodology to county-specific mortality data, various sources of uncertainty were accounted for, and informative influenza mortality maps and profiles were generated. This methodology enabled the detection of significant effects of climate change on the influenza risk distributions. Geographical maps of risk variation during El Ni?o differed from those during normal weather, the corresponding covariances exhibited distinct space-time dependence features, and the temporal mean mortality profiles were considerably higher during normal weather than during El Ni?o. These rather unexpected results of spatiotemporal analysis are worth further investigation that seeks substantive and biologically plausible explanations. The findings of this study can offer a methodological framework to evaluate public health management strategies.  相似文献   

16.
A metrological approach is used for investigating out-of-specification (OOS) test results of total suspended particulate matter (TSP) mass concentrations in ambient air. As a case study, 496 test results of mass concentration of TSP in ambient air were obtained according to methods of the Environmental Protection Agency, USA. The samples, collected in 2009, came from the same geographic proximity in three stone quarries located in Israel. Twenty of the test results were OOS test results that exceeded the upper limit specified in the national air quality regulations. Investigation of the OOS test results indicated the fact that only 10% of these results (two out of 20) can be decidedly interpreted as witnesses of violations of the national air quality regulations. The other 90% were probably metrologically related, i.e., compatible with the national air quality regulations when considering the measurement uncertainty associated with the test results. Probabilities of future OOS test results and global risks of the stone producer and the consumer, who is defined as an inhabitant near a quarry, were estimated. Acceptance limits, resembling ??warning and action lines?? used in quality control charts, for air test results were calculated by taking into account the measurement uncertainty.  相似文献   

17.
The present observational study was designed to evaluate the effectiveness of the I Can Problem Solve (ICPS) programme on behavioural change from aggression to pro‐social behaviours by using the DECB rating scale. Non‐participant observation method was used to collect data in pretest‐training‐posttest design. It was hypothesised that the ICPS programme would be useful to decrease in aggressive behaviours, increase in pro‐social behaviours and also to improve in introverted behaviours. In total, 83 five‐ and six‐year‐old children attending public preschools participated in the study. Pro‐social and introvert behaviours of children in the experimental group were significantly improved compared to the control group. Although there was no significant difference statistically between pretest–posttest scores of experimental and control group, the mean scores of both groups differentiated considerably.  相似文献   

18.
This study identifies factors associated with walking among postmenopausal women and tests whether neighborhood walkability moderates the influence of intrapersonal factors on walking. We used data from the Women's Health Initiative Seattle Center and linear regression models to estimate associations and interactions. Being white and healthy, having a high school education or beyond and greater non-walking exercise were significantly associated with more walking. Neighborhood walkability was not independently associated with greater walking, nor did it moderate influence of intrapersonal factors on walking. Specifying types of walking (e.g., for transportation) can elucidate the relationships among intrapersonal factors, the built environment, and walking.  相似文献   

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Previous studies on the influence of mixed groupings within preschool classrooms have indicated positive effects on children’s development. This study extended earlier findings to determine the effects of socioeconomic diversity within the classroom on the language, cognitive and social–emotional development of preschool children of low‐income backgrounds. Twenty‐seven preschool children were enrolled in two classrooms in a private university’s child development center. Twenty of the 27 enrolled were from low‐income backgrounds. The children were tested to determine a baseline measure of their language, cognitive and social–emotional skills. Classroom observations of the children’s language behavior were coded. Post‐testing was done at the conclusion of the school year to determine growth in language, cognitive and social–emotional skills. Differences in language usage and social–emotional development were observed. These results suggest that mixed income grouping as well as teacher interactions influence language and social–emotional development of children from low‐income backgrounds.  相似文献   

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