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101.
Beyond low‐density lipoprotein (LDL)‐cholesterol concentrations, in recent years, several clinical studies have shown that both oxidised and small, dense LDL have a strong predictive role for the presence of vascular atherosclerosis. These two lipid parameters seem to have a synergistic impact on cardiovascular risk, with a greater importance in patients at higher‐risk, such as those with type‐2 diabetes. Increased levels of oxidised and small, dense LDL levels are a feature of diabetic dyslipidaemia, and small, dense LDL have been shown to be a good predictor of future cardiovascular events, at both univariate and multivariate analyses. On the other hand, although the association of oxidised LDL with surrogate markers of atherosclerosis is consistent, the correlation with hard clinical end points seems to be smaller. Yet, measurement of these two lipid parameters has not been widely used in daily practice because of the limited availability of clinical data and methodological problems: lack of availability of easy, cheap and reproducible essays for measurement of oxidised and, particularly, small, dense LDL has reduced their assessment in large clinical end‐points trials. However, on the basis of available data, the therapeutic modulation of small, dense LDL is significantly associated with reduced cardiovascular risk, even after adjustment for confounding factors. In conclusion, the routine measurement of oxidised and small, dense LDL in patients with type‐2 diabetes cannot be recommended in daily clinical practice so far; yet, their measurement is strongly encouraged to better understand their role on the cardiovascular risk of patients with type‐2 diabetes.  相似文献   
102.
103.
We examined mortality in a retrospective follow-up study of 3,241 workers employed between 1970–1992, in four pulp and paper mills in Catalonia, Spain. Vital status was determined for 95% of the cohort. Exposure was reconstructed using job histories and a company exposure questionnaire. Standardized mortality ratios (SMR) were derived using mortality rates of Spain as the reference. For all workers, mortality from all causes (SMR = 76; 95%; confidence intervals [CI] = 65–88; 189 deaths) and all malignant neoplasms (SMR = 93; CI = 72–119; 65 deaths) were less than the expected. Excess risk was observed for mortality from all neoplasms in females (SMR = 168; CI 84–303; 11 deaths), for large intestine cancer in both sexes (SMR = 250; CI = 115–525; 8 deaths), particularly after 10 years of employment and latency (SMR = 355; CI = 154–701; 8 deaths), and for breast cancer in females (SMR = 286; CI = 77–732; 4 deaths). These findings suggest that workers employed in the pulp and paper industry may have an excess risk of specific cancers. © 1996 Wiley-Liss, Inc.  相似文献   
104.
105.
OBJECTIVE: To assess the presence of socio-economic differences in bladder cancer in a heavily industrialised area of Catalonia, Spain and to evaluate risk factors associated with the presence of these differences. METHODS: 218 cases and 344 population controls resident in the area of Vallès Occidental, Barcelona, were identified prospectively and interviewed during 1993-1995. Socio-economic level was evaluated through attained education and social class on the basis of the last and longest held occupation. Logistic regression was used to derive adjusted odds ratios and 95% confidence intervals. RESULTS: There was no association between education and bladder cancer risk. Social class, evaluated on the basis of longest held job, was weakly related with bladder cancer, with the highest risk occurring in the highest social classes. This pattern was more pronounced when the analysis was done using the last occupation. Occupational exposures modified minimally these results. Among controls, the overall prevalence of smoking did not differ between social class but the prevalence of heavy-smokers (> 48.76 packs-year) was highest among subjects in social class V (35.5%) and lowest in social class I (10%). Adjusting for smoking enlarged social class differences. CONCLUSION: Similarly to the pattern in other European countries, no pronounced differences by social class were observed for bladder cancer in this area of Catalonia. The evaluation of social class patterns was crucially affected by the type of socioeconomic information examined. Measures of life-time experience should be preferred rather than socio-economic level at the time of the disease. Smoking seems to be one of the main mediators for the occurrence of bladder cancer differentials but other, yet unidentified risk factors, must be associated with bladder cancer risk, especially among the highest social classes.  相似文献   
106.
AIMS: To investigate the susceptibility of implantable cardioverter defibrillators to electromagnetic interference generated by digital cellular telephones, functioning in both international transmission technologies: the Global System for Mobile Communication (GSM) and the Digital Cellular System (DCS 1800). METHODS AND RESULTS: In 36 patients with transvenous implantable cardioverter defibrillators from two manufacturers (Medtronic and Guidant/CPI), cellular telephones with different levels of minimal and maximal power output were tested in the transmitting and receiving mode. Evaluation was performed in activated implantable defibrillators during spontaneous cardiac activity and continuous VVI or DDD pacing to assess possible electromagnetic interference. In two patients, appropriateness of ventricular fibrillation detection and therapy was judged during telephone testing. There was no damage, reprogramming, inappropriate shock therapy or pacing inhibition during the tests. In seven pre-pectoral Medtronic implantable defibrillators, transient electromagnetic interference caused 19 erroneous sensing events, when the operating phone was held in close vicinity to the programmer head. These 'pseudo-oversensing' events, which did not result in logging of arrhythmia episodes in the device counter, were interpreted as an adverse interaction between the telephone and the programming device. CONCLUSION: Digital cellular telephones do not represent a risk to Medtronic and Guidant/CPI recipients of the specific implantable defibrillator models herein tested.  相似文献   
107.
Acute coronary syndromes are the result of coronary plaque rupture in the majority of cases. Available diagnostic techniques that focus on the early detection of plaques that are prone to rupture are still limited. Increased neovascularization in the vasa vasorum of the atherosclerotic plaque has been identified recently as a common feature of inflammation and plaque vulnerability. Microbubbles, which have been used for ultrasound imaging, can be used to trace neovascularization. We present recent advances in contrast agents and contrast-enhanced intravascular ultrasound that may be used for the detection of vasa vasorum, including fundamental and harmonic contrast imaging. Identification of vasa vasorum proliferation in atherosclerotic plaques presents important clinical implications; in particular it could provide a means to detect vulnerability in vivo, thereby guiding targeted treatments.  相似文献   
108.
Kheradpour P  Stark A  Roy S  Kellis M 《Genome research》2007,17(12):1919-1931
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109.
BACKGROUND: Many studies have reported the prevalence of sensitization using skin prick tests. However, comparisons between studies and between regions are difficult because the number and the type of allergens tested vary widely. Using the European Community Health Respiratory Survey I data, the geographical variation of sensitization to environmental allergen as measured by skin tests was established. METHODS: Adults aged 20-44 years, living in 35 centres in 15 developed countries, underwent skin tests for allergy to nine common aeroallergens: Dermatophagoides pteronyssinus, timothy grass, cat, Cladosporium herbarium, Alternaria alternata, birch, Olea europea, common ragweed and Parietaria judaica. The age-sex standardized prevalence of sensitization was determined and centres with high (95% confidence interval above and excluding study median) and low prevalence (95% confidence interval below and excluding study median) of sensitization to each allergen and to any of the nine allergens were identified. RESULTS: There was substantial geographical variation in the prevalence of sensitization to each of the nine allergens tested and in the prevalence of sensitization to any allergen (lowest 17.1%, median 36.8% and highest 54.8%). Sensitization to D. pteronyssinus, grass pollen and cat were usually the most prevalent (median between centre 21.7%, 16.9% and 8.8%, respectively). Timothy grass sensitization was higher than that for any other pollen species. CONCLUSIONS: As expected, geographical variations of sensitization to environmental allergen were observed across centres. These findings were compatible for those observed with serum-specific IgE. Skin tests can be used to assess the geographical distribution of allergens in a multicentric epidemiological survey.  相似文献   
110.

Objectives

Reported associations of self‐employment with occupational injury and cerebrovascular disease suggest that worker safety and health precautions may vary by occupational status. The authors assessed the extent to which use of respiratory protection and ventilation equipment is associated with self‐employed versus employee status among adults in an international study.

Methods

The European Community Respiratory Health Survey II (ECRHS II) is a follow‐up study conducted in a population‐based random sample of adult ECRHS I participants. Men and women enrolled in the ECRHS II completed interviewer‐administered questionnaires to provide information about their occupational status and job history during the 9‐year ECRHS follow‐up period. Respondents in selected occupational groups completed supplemental questionnaires about their jobs and use of respiratory protection and ventilation equipment on‐the‐job. The authors assessed self‐reported use of respiratory and ventilation equipment among 72 self‐employed and 371 employed adults in metalworking, soldering and welding occupations.

Results

Local exhaust ventilation (fixed extraction: OR 0.37, 95% CI 0.17 to 0.80; mobile extraction: OR 0.23, 95% CI 0.09 to 0.60; on‐tool extraction: OR 0.39, 95% CI 0.18 to 0.88) was reported less frequently among self‐employed respondents than among employed respondents. The magnitude of the negative association between self‐employment status and any of the three types of local exhaust ventilation was not attenuated by adjustment for duration of work per day or week or asthma and/or wheezing symptoms. Respiratory protection was not associated with employment status in these data.

Conclusions

More limited use of local exhaust ventilation among self‐employed workers compared to employees suggests the need to promote occupational safety among self‐employed workers.Information about the working conditions of employees may not reflect the experiences of self‐employed individuals working in the same fields. Self‐employed people who work independently or operate their own businesses may take advantage of the increased autonomy often associated with self‐employment to organise their work schedules and practices to more closely suit their professional preferences. In many industries, self‐employed workers have the opportunity to select their own hours, work settings, clients and equipment. Workers with this degree of flexibility may develop their own occupational health and safety practices, but existing information describing the working conditions of self‐employed individuals is insufficient to indicate how practices differ from those of employees, or how these differences affect health and safety.Recent research provides evidence that health and safety precautions and job training vary between workers in self‐employed and employed work situations.1 Results from a 2005 survey conducted in the EU indicate that self‐employed workers experienced greater autonomy and less violence, harassment and/or discrimination on the job and had fewer days of health‐related absence over the past year compared to employed respondents. In contrast, the self‐employed respondents more frequently reported that they considered their health and safety to be at risk because of work and a slightly smaller percentage reported wearing personal protective clothing or equipment at work (self‐employed 29% vs employed 35%).1 Although the survey did not include industry‐ or job‐specific estimates or health outcomes related to the use of personal protective equipment, overall these responses reveal some of the reasons individuals may seek self‐employment situations, and raise the possibility that self‐employed work arrangements may result in important health and safety risks.Previous research has shown differences in the rates of work‐related mortality among the self‐employed and privately‐employed populations.2,3 For example, using data reported through a medical examiner''s surveillance system, notably higher fatal occupational injury rates were observed among self‐employed workers in the agricultural sector and in retail and transportation industries.2 The surveillance‐based study found lower rates among self‐employed workers in the construction industry, suggesting differences in the occupational health and safety practices of self‐employed and employed individuals.2 Such variations in the rates of occupational injury may reflect differences in work‐related tasks, settings, use of protective equipment or differences in the age and/or levels of work experience between the two populations. In contrast, lower rates of cerebrovascular disease have been reported among self‐employed men than among employed men. Although the differences were not observed for overall mortality or other circulatory disorders, the investigators concluded that the effect of self‐employment status was independent of those associated with other lifestyle and medical factors and thus may be considered an additional determinant of health.4 Differences in mortality rates between self‐employed and employed populations led the investigators to suggest considering employment status as a proxy for differences in working practices, including the physical work environment.Despite these observed differences in occupational practices, mortality and cardiovascular morbidity, occupational health and safety practices of self‐employed workers remain largely unreported in the public health literature. For this analysis, we investigated a hypothesis for which there is little epidemiological evidence—that is, whether employment status is associated with use of respiratory protection and/or ventilation equipment. We used data from the European Community Respiratory Health Survey (ECRHS), a population‐based cohort of adult men and women, to examine self‐reported use of respiratory protection and ventilation equipment among self‐employed and employed respondents.  相似文献   
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