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31.
A methodological overview is provided on the important question of how to confirm occupational asthma in routine work. Recent knowledge gained in immunology and occupational allergy has been utilized, supplemented by an overview of recent publications on the diagnosis and pathophysiology of occupational asthma. The aim of the paper is to facilitate decision making for an investigator dealing with individual cases of occupational asthma. Moreover, by presenting stepping-stones in the diagnostic cascade, the author hopes to encourage the less experienced to conduct a comprehensive and cause-oriented diagnostic procedure. Methods which are being worked on at present (standardization) are discussed in more detail. Finally, the research goals in the understanding, confirmation, and prevention of occupational asthma are listed.  相似文献   
32.
The present study describes cause-specific mortality of asbestos cement workers in the Emilia Romagna region of Italy. The cohort included workers in ten factories, most of which started operating between 1955 and 1965. Asbestos, mainly chrysotile, constituted 10%–20% of the dry component of the mixture. Crocidolite range between 5% and 50% of total asbestos. Asbestos concentrations up to 44 ff/cc were reported prior to 1975, while in recent years they have usually been below 0–1 ff/cc. The cohort included 3341 workers who had at some time been employed in the ten factories under study. Their mortality experience was compared with that of the population resident in Emilia Romagna. Vital status was ascertained at 1989. Seventy-three subjects were lost to followup (2.2%). Mortality from all causes and from all types of cancer was increased in the cohort. Malignant neoplasms of the respiratory tract showed a significant increase (SMR: 134; 90% confidence interval: 101–175; 40 observed) due to lung cancer (SMR: 124; 90% confidence interval: 91–166; 33 observed) and neoplasms of the pleura, mediastinum, and other parts of the respiratory tract (SMR: 602; 90% confidence interval 237–1267; 5 observed). The discrepancy between observed and expected mortality mainly concerned subjects with at least 20 years of employment in the factories. Five more cases of histologically confirmed mesothelioma occurred after the end of follow-up.  相似文献   
33.
Toluene in blood as a marker of choice for low-level exposure to toluene   总被引:1,自引:1,他引:0  
The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels.  相似文献   
34.
In October 1990 pneumonia due toLegionella pneumophila was diagnosed in two employees working in the area of Apulia, southern Italy, where artesian wells were in construction. Although the exposure to excavation has been associated with Legionnaires' disease, in our investigation the illness occurred only in those employees who were present when the water emerged from the ground under high pressure. On the basis of this report, water appears as the most likely reservoir of the organism and the main route of infection.Corresponding author.  相似文献   
35.
Summary During an epidemiological survey on arc welders, serum copper and ceruloplasmin were determined in two groups of workers. One group consisted of aluminum welders who were divided into two groups: 13 welders working inside aluminum tanks (confined atmosphere) and 8 welders engaged in the production of vans for dump trucks (nonconfined atmosphere). The reference group consisted of 26 workers of the same plant who were not exposed to welding fumes. Ozone, the major pollutant in aluminum arc welding, was thought to be the principal factor in the significant decrease (P < 0.01) of mean ceruloplasmin in confined welders. This decrease in the level of ceruloplasmin was still within the reference values and was not linked to age or to tobacco consumption. We found a linear relationship between ceruloplasmin concentration and the cumulated worktime along the week. This effect could be a sign in the serum of a lung reaction against oxidant activity in this type occupational exposure.  相似文献   
36.
The present study examined four potential roles of work-related negative affectivity on the associations between self-reported occupational stress and physical well-being among telecommunication employees in Greece. Participants (764, predominantly male) completed a battery of self-report measures on perceived occupational stress, negative affectivity, and illness symptoms. In line with previous research, negative affectivity exerted a nuisance effect, by inflating the association between reported stressors and illness symptoms, and significantly predicted illness symptoms, over and above the effects of stressors. In addition, negative affectivity influenced reported illness symptom indirectly, through the effects of stressors, and moderated the relationship between interpersonal conflict at work and illness symptoms. The findings suggest that negative affectivity can largely explain and influence in different ways the associations between self-reported stress and physical strain. It is recommended that future studies of occupational stress should control for the effects of negative affectivity, and that health professionals should be cautious of its effects when interpreting relationships between self-reported occupational stress and physical well-being.  相似文献   
37.
BACKGROUND: Prepulse inhibition (PPI) is an operational measure of sensorimotor gating and is impaired in a family of neuropsychiatric disorders characterized by abnormalities of inhibitory function. Adults with autistic disorder (AD) exhibit clinical features of inhibitory deficits, such as restrictive and repetitive behaviors, that may be explained by deficits in sensorimotor gating. METHODS: Acoustic startle reactivity, habituation, and PPI (30-, 60-, 120-msec interstimulus intervals) were assessed in 14 adult men diagnosed with AD and 16 typically developing normal comparison (NC) participants. All participants were administered measures of intelligence and frontal-executive functioning. RESULTS: Adults with AD exhibited significantly less PPI in the 60-msec condition than NC participants, which was correlated with increased ratings of restricted and repetitive behaviors. The groups did not differ on measures of startle amplitude or overall habituation. There was, however, a significant group-by-block habituation effect. Furthermore, PPI was not related to intelligence but was moderately associated with performance on a measure of frontal-executive functioning. CONCLUSIONS: Adults with AD have sensorimotor gating deficits similar to other neurodevelopmental disorders, implicating a failure of normal inhibitory regulation of sensory, motor, and attentional mechanisms. Thus, PPI deficits may be indirectly linked to one of the hallmark features of AD.  相似文献   
38.
某化工厂1987~2000年164例工伤事故调查分析   总被引:2,自引:0,他引:2  
目的调查分析某化工厂工伤事故的分布规律及其危险因素,以便采取相应的预防干预措施。方法对1987~2000年该化工厂发生的工伤事故进行回顾性调查分析,建立数据库,并统计分析。结果 ①事故以轻伤为主,约占80.0%。②事故类别主要是灼烫烧伤和机械伤害,分别为工伤事故总数的35.8%、28.5%。③工伤伤害性质以骨折多见,约为总数的56.1%。④受伤工人的年龄分布以30~40岁段为主,约为总数的31.1%。⑤工伤事故原因中注意力不集中和违反操作规程分别为总数的43.0%,38.3%。结论12根据上述流行病学特点,采取相应的措施来减少工伤事故的发生。  相似文献   
39.
On-site testing of 157 poultry processors disclosed that 50% had three or more abnormal upper extremity findings out of a total of 22 possibles. The average worker had five to six abnormal findings. Impaired pinch strength, decreased vibration sensitivity in the fingertips, and reports of current numbness were the most prevalent. Of workers with signs, 25% reported no symptoms, whereas only 8% of workers reported symptoms but had no signs. The investigators concluded that this measurement method has utility for assessments of worker populations to determine prevalence of CTDs and, potentially, for preclinical detection of these disorders to permit early intervention, reduce medical costs, and minimize disability. The need for accurate measurement to enhance early detection and prevention is discussed.  相似文献   
40.
The penis, scrotum, and testicles of a 31-year-old man were cut off in a fight. Fourteen hours later the penis and one testicle were reattached, but the testicle later had to be removed. By 3 weeks normal urinary function returned but the penis was misshapen. The patient had suicidal intentions. His partner was sexually supportive but afraid to touch the penis. By 10 weeks penile swelling occurred in response to a movie with frank sexual content. By 12 weeks the penile swelling was sufficient for entry but the partner was acutely afraid that her vaginal contractions would tear the scars. The man was concerned because he experienced only mild sexual tensions. Physical examination reassured both, and they gained hope for recovery. At 16 weeks erections were still not full but active intercourse was attempted and he experienced seminal seepage and mild orgasmic sensations; she was relaxed enough to have orgasm. Testosterone was administered at regular intervals from the 19th week on, with immediate improvement of erection. By 32 weeks full erection, ejaculation, and orgasmic functions returned and the couple resumed their normal sexual practices.  相似文献   
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