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101.
A panel of 377 healthy adults and 920 COPD patients aged 30–65 years, is annually interviewed (ATS-NHLI health questionnaire) and performs pulmonary function test (PFT), which includes: FVC, FEVI, FEVl/FVC, PEF, FEF50 and FEF75. Baseline data analysis showed a more significant excess in respiratory symptmos (8.8% to 21.4%) and lower PFT (2.4% to 8.0%) among patients occupationally exposed to dust, than among healthy exposed panelists (-0.7% to 7.7% excess symptomatology and -0.3 to 5.8% lower PFT). Among patients a significant correlation between PFT and degree of occupational dust exposure was found. Significantly lower FEVl/FVC and excess in respiratory symptoms (with relative risks of 2.47–16.38) was present in healty smokers vs. non smokers as compared with COPD patients.Corresponding author. 相似文献
102.
Martha Stanbury Gwendolyn Solice-Sample John Pescatore 《American journal of industrial medicine》1993,23(1):97-104
Since October 1985, the New Jersey Department of Health (NJDOH) has required hospitals to report all patients with a discharge diagnosis of asbestosis. As follow-up to a needs assessment survey of these patients, the NJDOH developed an educational packet including an information bulletin titled “Asbestos Disease: Medical and Legal Facts for Employees” and a pre-stamped postcard evaluation survey. The packet was sent to 1,418 patients reported by hospitals; 433 patients returned the evaluation questionnaire. The survey assessed attitudinal responses (were the materials helpful and easy to understand?) and behavioral responses (did the respondent plan on discussing the materials with a doctor or lawyer?) to the information in the packet. Of the postcard respondents, 85% found the materials helpful, and approximately half indicated that they would discuss the materials with a doctor or lawyer. Of the 33% who were proxy respondents, half appeared not to have understood that the materials had relevance to them as family members. Modifications to the protocol for the asbestos disease educational packet were made based on the evaluation data. Limitations of the evaluation survey and the value of process evaluations in risk communication projects are discussed. © 1993 Wiley-Liss, Inc. 相似文献
103.
topic . How impaired personal boundaries play a significant role in mental illnesses and co-dependency.
purpose . To demonstrate the value of having a formal nursing diagnosis of "impaired personal boundaries."
source . A concept analysis of personal boundaries, which describes the physical, emotional, intellectual, and spiritual dimensions of personal boundaries.
conclusion . The author recommends a new nursing diagnosis of "impaired personal boundaries," which provides a basis for the plan of care for clients with this difficulty. 相似文献
purpose . To demonstrate the value of having a formal nursing diagnosis of "impaired personal boundaries."
source . A concept analysis of personal boundaries, which describes the physical, emotional, intellectual, and spiritual dimensions of personal boundaries.
conclusion . The author recommends a new nursing diagnosis of "impaired personal boundaries," which provides a basis for the plan of care for clients with this difficulty. 相似文献
104.
J. Stelling H. Dupuis 《International archives of occupational and environmental health》1996,68(4):236-242
Under laboratory conditions the effects of single-axis and multi-axis hand-arm vibration exposure on several strain parameters were tested in up to 20 male subjects. As parameters of these acute effects, the biodynamic vibration behavior of the hand-arm system, the electrical activity of the most affected muscle groups, the skin temperature, the vibration sensitivity of the fingertips, and the subjective vibration sensation were measured. When comparing simulated three-axis vibration exposure with single-axis vibration exposure, synergistic effects in the form of an increasing reaction could be found. It could be proven that the vector sum of the frequency-weighted acceleration in the three axes represents the acute effects better than does the weighted acceleration in the main axis alone. This summation has to take into account the relatively lower effects of vibration in the x- or y-direction compared with the z-direction. On the basis of the experimental results a new proposal for frequency weighting of the three different axes and an energetic summation procedure are derived. Application of this knowledge in the International Standard ISO 5349 is proposed. 相似文献
105.
Summary Substantiation of relevant asbestos risks by microscopic examination sets a lower detection limit at fibres longer than 5 to 10 m and thicker than 0.5 m Such microscopically detectable fibres are, of course, in respect to total quantity the insignificant part of the overall dust burden, but apparently a necessary part of the whole fraction when assessing the relevance of exposure. Until now, no epidemiologically conclusive asbestos risks resulting from occupational exposure have been made known solely with fibre fraction below the microscopic detection limit. Demands for supplementary electromicroscopic examination on the basis of case reports of lung parenchyma damage by fibres of a lower calibre than the microscopic detection limit are, therefore, presently without foundation. The subject examinations reveal that substantiation of asbestos risks with light-optical means, using different methods, provides comparable results. Initially, of course, it is surprising to obtain fluctuations in results of 100000 to 600000 asbestos particles for the same case. However, one must realize that calculations based on intermediate results are responsible for this range of fluctuation, due to the varying degree of asbestos fibre dispersion in the different sections of the lung and, depending on the method of detection used. Interest on the part of everyday occupational medicine and expert opinion is determined by the need to categorize individual cases into different basic classes of risk by referring to relevant morphological facts, such as substantiation of asbestosis or drawing a borderline between persons with occupational risk and those with a non-occupational risk. The subject examinations reveal, using different methods of analysis, equally significant results, which correspond with those published by other authors who used a method which, in terms of expenditure for material and manpower, is also suitable for routine analysis. 相似文献
106.
背景 呼出气一氧化氮(FeNO)的测量具有安全、无创、简便、重复性好等特点已经被广泛应用于哮喘患者气道炎症的评估,但FeNO的测定结果受到多种因素的影响,生活环境因素暴露可能与FeNO水平有较为密切的关系,而目前关于生活环境因素暴露对FeNO水平影响的研究较少。目的 分析生活环境因素暴露对支气管哮喘非急性发作期患者FeNO水平的影响,以提高临床医生利用FeNO管理哮喘的效能。方法 纳入2018年7月至2020年6月就诊于广州医科大学附属第二医院呼吸内科门诊的109例支气管哮喘非急性发作期患者作为研究对象,通过问卷调查的方法收集资料,问卷信息主要包括一般资料(性别、年龄、身高、体质量)、生活环境因素(包括吸烟史,家人在家是否吸烟,过敏史,居住地位置,居住地离车流量大的主干道位置,居住地周围有无工厂,居住房屋楼层,房屋居住年限,床单、被/枕套清洗晾晒的频率,家中窗帘材料,家中有无盆栽花草,家中垃圾桶有无定期清洗,家中有无饲养宠物,家中有无蟑螂,厨房垃圾有无当天处置,家中是否有毛绒玩具),并收集FeNO的检查资料。根据FeNO水平将支气管哮喘患者分成3组:FeNO低水平组(FeNO<2... 相似文献
107.
Potentiation of allergic bronchoconstriction by repeated exposure to formaldehyde in guinea-pigs in vivo 总被引:2,自引:0,他引:2
T. Kita M. Fujimura S. Myou Y. Ishiura M. Abo N. Katayama M. Nishitsuji Y. Yoshimi S. Nomura Y. Oribe S. Nakao 《Clinical and experimental allergy》2003,33(12):1747-1753
BACKGROUND: Indoor formaldehyde (FA) might worsen allergies and be an underlying factor for the increasing incidence and severity of asthma; the exact mechanism, however, remains unclear. OBJECTIVE: The present study examined the effects of repeated exposure to FA on methacholine- and antigen-induced bronchoconstriction in guinea-pigs in vivo. METHODS: First, non-sensitized guinea-pigs were transnasally treated with 0.1 or 1.0% FA or saline three times a week for 6 weeks, and increasing concentrations of methacholine (50, 100, and 200 microg/mL) were inhaled at 5-min intervals. Second, guinea-pigs pre-treated with transnasal administration of FA or saline using the same protocol were passively sensitized with anti-ovalbumin (OA) serum 7 days before antigen challenge. Third, guinea-pigs were actively sensitized with OA and pre-treated with transnasal administration of FA or saline using the same protocol. The lateral pressure of the tracheal tube (Pao) was measured under anesthesia and artificial ventilation. RESULTS: The antigen-induced increase in Pao in actively sensitized guinea-pigs was significantly potentiated by FA exposure in a dose-dependent manner. The dose-response curve of the methacholine-induced increase in Pao in non-sensitized guinea-pigs or of the antigen-induced increase in Pao in passively sensitized guinea-pigs was not altered by FA exposure. Transnasal administration of FA significantly increased the serum anti-OA homocytotropic antibody titre (IgG) as measured by the passive cutaneous anaphylaxis reaction in actively sensitized guinea-pigs. CONCLUSION: The results suggest that repeated exposure to FA worsens allergic bronchoconstriction through enhancing antigen sensitization. 相似文献
108.
Male mice, genetically selected for differences in brain weight or from a heterogeneous (HET) stock, were used to explore potential interactions between genotype and exposure to lead as manifested in activity. At the time of birth dams and their pups were given either water or a 0.5% lead acetate solution as the sole source of fluid. Fluid conditions remained constant throughout the experiment. The effects of chronic lead on activity in young adult mice depended on the genotype of the individual. Specifically, in an open field, HET mice exposed to lead tended to be more active than their control counterparts. Low-and high-brain weight lead-exposed mice at times were hypoactive but this effect depended on the specific nature of the measure.This research was supported in part by National Science Foundation Grant DAR7911233 to Peter J. Donovick and Richard G. Bruggight and by Biomedical Research Support Group Grant 5S077RR07149 to Peter J. Donovick. 相似文献
109.
We evaluated human physiological responses and the performance of manual tasks during exposure to severe cold (–25°C) at
night (0300–0500 hours) and in the afternoon (1500–1700 hours). Thirteen male students wearing standard cold protective clothing
occupied a severely cold room (–25°C) for 20 min, and were then transferred to a cool room (10°C) for 20 min. This pattern
of exposure was repeated three times, for a total time of exposure to extreme cold of 60 min. The experiments were started
either at 1500 hours or 0300 hours and measurements of rectal temperature, skin temperature, blood pressure, performance in
a counting task, hand tremor, and subjective responses were made in each condition. At the end of the experiment at night
the mean decrease in rectal temperature [0.68 (SEM 0.04)°C] was significantly greater than that at the end of the experiment
in the afternoon [0.55 (SEM 0.08)°C, P<0.01]. After the second cold exposure at night the mean increase in diastolic blood pressure [90 (SEM 2.0) mmHg] was significantly
greater than that at the end of the second cold exposure in the afternoon [82 (SEM 2.8) mmHg, P<0.01]. At the end of the second cold exposure at night, mean finger skin temperature [11.8 (SEM 0.8)°C] was significantly
higher than that at the comparable time in the afternoon [9.0 (SEM 0.7)°C, P<0.01]. Similarly for the toe, mean skin temperature at the start of the second cold exposure at night [25.6 (SEM 1.5)°C]
was significantly higher than in the afternoon [20.1 (SEM 0.8)°C, P<0.01]. The increased skin temperatures in the periphery resulted in increased heat loss. Since peripheral skin temperatures
were highest at night, the subjects noted diminished sensations of thermal cold and pain at that time. Manual dexterity at
the end of the first cold exposure at night [mean 83.7 (SEM 3.6) times·min–1] had decreased significantly more than at the end of the first cold exposure in the afternoon [mean 89.4 (SEM 3.5) times·min–1, P<0.01]. These findings of a lowered rectal temperature and diminished manual dexterity suggest that there is an increased
risk of both hypothermia and accidents for those who work at night.
Electronic Publication 相似文献
110.
Dr. S. Ichioka M. Iwasaka M. Shibata K. Harii A. Kamiya S. Ueno 《Medical & biological engineering & computing》1998,36(1):91-95
There have been few studies of the effect of static magnetic fields on microcirculatory haemodynamics in vivo. The rat skinfold
transparent chamber technique was used, which provides an excellent means of observing and quantifying direct in vivo microvascular
haemodynamic responses to static magnetic fields up to 8 T. An intravital videomicroscope was used to measure the changes
in blood flow before and after exposure to a magnetic field for 20 min in a horizontal type superconducting magnet with a
bore 100 mm in diameter and 700 mm long. After exposure, microcirculatory blood flow showed an initial increase for about
5 min followed by a gradual decrease and a return to the control value. It is hypothesised that these changes represent rebound
hyperaemia following reduced blood flow during exposure. 相似文献