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101.
102.
Marco Lembo Carmela Vedetta Umberto Moscato Michele del Gaudio 《La Medicina del lavoro》2021,112(2):123
Introduction:Due to the COVID-19 pandemic, healthcare workers are now required to use additional personal protective equipment (PPEs) to protect themselves against the virus. That led to an increased clothing insulation which is negatively affecting the perceived healthcare workers’ thermal sensation.Objectives:While demonstrating through software simulations the potential level of thermal discomfort healthcare workers involved in the COVID-19 emergency can be subjected to, this work aims at identifying measures to improve thermal sensation perception and acceptable thermal conditions for medical personnel.Methods:After having obtained the insulation values of individual clothing used by staff during COVID-19 emergency through the use of a thermal well-being evaluation software, the Fanger indexes (PMV - Predicted Mean Vote and PPD - Predicted Percentage of Dissatisfied) were calculated in order to estimate staff satisfaction to microclimatic conditions.Results:The use of COVID-19 additional PPEs with an air temperature equal to 22 °C (normally considered optimal) brings the PMV index equal to 0.6, which corresponds to 11.8 % being unsatisfied (PPD) due to perceived heat.Discussion:The use of additional protective devices significantly increases the clothing insulation level, facilitating the onset of conditions of thermal discomfort in the health workers. Workers engaged in the execution of nasopharyngeal swabs were most affected by the summer weather conditions and certainly represent the most critical category, for which it would be recommended to implement a higher turnover of service to reduce individual exposure time and consequent discomfort. 相似文献
103.
104.
Hans J. Seitz Wilhelm Krone Harald Wilke Wolfgang Tarnowski D. Carsten B. Dunkelmann A. Harneit 《Pflügers Archiv : European journal of physiology》1981,389(2):115-120
The effect of acute cold exposure on the concentration of glucagon in the blood was investigated in man and in intact and adrenalectomized rats.In man fasted overnight acute cold exposure, which caused a twofold increase in O2-consumption resulted in a rapid rise in plasma glucagon. The levels of insulin and blood glucose remained unaltered, while the concentration of serum free fatty acids and -hydroxybutyrate increased.In fasted intact rats acute cold exposure lead to similar effects. A close parallelism between the rise in plasma glucagon and the concentration of hepatic cycloAMP was observed. Adrenalectomy did not impair the cold induced rise in plasma glucagon and hepatic cycloAMP.It is concluded that acute cold exposure caused a rapid rise in the concentration of plasma glucagon leading to an increase in the concentration of hepatic cycloAMP, thus enhancing the rate of hepatic gluconeogenesis and ketogenesis. As these alterations were similar in the absence of glucocorticoids and medulla-derived catecholamines, it is suggested that glucagon may play a role in the metabolic adaptation to acute cold exposure. 相似文献
105.
Elevated binding activity of CD8+ cells with phytohaemagglutinin by asbestos fibre in vitro. 下载免费PDF全文
K Kinugawa F Hyodoh A Andoh A Ueki H Tanaka Y Mochizuki 《Clinical and experimental immunology》1990,80(1):89-93
Asbestos fibres are known to depress the mitogenic stimuli of phytohaemagglutinin (PHA) to lymphocytes. We examined effects of asbestos (chrysotile) fibre on the proliferation of PHA-stimulated lymphocytes and the PHA binding activity of lymphocytes in vitro. The incorporation of 3H-thymidine and the expression of interleukin-2 receptor were depressed when the cells were exposed to 50 micrograms/ml of chrysotile fibre. The PHA binding activity of lymphocytes was significantly enhanced after chrysotile fibre exposure, as compared with non-exposed group. These results indicate that the depression of PHA stimuli with chrysotile fibre was not due to blocking of PHA binding to lymphocytes. The enhancement of PHA binding activity by chrysotile fibre was observed on CD8+ but not on CD4+ cells. It is possible, therefore, that treatment of peripheral blood mononuclear cells with chrysotile fibre induces increased reactivity of CD8+ cells with PHA, and that intensely activated CD8+ cells suppress proliferation of lymphocytes. 相似文献
106.
Kvacheva ZB Shukanova NA Votyakov VI Lobanok ES Vorobei AV Nikolaeva SN 《Bulletin of experimental biology and medicine》2003,135(4):384-387
Membranotropic amphiphilic chromophore merocyanine 540 sensitized photodynamic inhibition of drug-resistant and sensitive variants of type I herpes simplex virus in cultured Vero cell. Optimal conditions of photodamage to virus particles and infected cells were determined (merocyanine 540 concentration 1 M, illumination dose 32.5-65.0 kJ/m2, exposure at early stages of infection). Infected cells actively bind the photosensitizer, which explains their selective photodamage. 相似文献
107.
High exposures to organic solvents among graffiti removers 总被引:3,自引:0,他引:3
Helena Anundi Marie-Louise Lind Lennart Friis Nadja Itkes Sven Langworth Christer Edling 《International archives of occupational and environmental health》1993,65(4):247-251
Summary The exposure to organic solvents among 12 graffiti removers was studied. Health effects were also assessed by structured interview and a symptom questionnaire. Blood and urine samples were collected at the end of the day of air sampling. The concentrations of dichloromethane, glycol ethers, trimethylbenzenes and N-methyl-2-pyrrolidinone in the breathing zone of each worker were measured during one working day. The 8-h time-weighted average exposure to dichloromethane ranged from 18 to 1200 mg/m3. The Swedish Permissible Exposure Limit value for dichloromethane is 120 mg/m3. The air concentrations of glycol ethers, trimethylbenzens and N-methyl-2-pyrrolidinone were low or not detectable. No exposure-related deviations in the serum concentrations of creatinine, aspartate transaminase, alanine transaminase, -glutamyl transpeptidase or hyaluronan or the urine concentrations of 1-microglobulin, R2-microglobulin or N-acetyl--glucos-aminidase were found. Irritative symptoms of the eyes and upper respiratory tract were more prevalent than in the general population. This study demonstrates that old knowledge about work harzards is not automatically transferred to new professions. Another aspect is that the public is also exposed as the job is performed during daytime in underground stations. At least for short periods, bystanders may be exposed to high concentrations of organic solvent vapours. People with predisposing conditions, e.g. asthmatics, may risk adverse reactions. 相似文献
108.
Quantitative measurements of vibration threshold in healthy adults and acrylamide workers 总被引:3,自引:0,他引:3
Hai Deng Fengsheng He Shoulin Zhang Carl J. Calleman Lucio G. Costa 《International archives of occupational and environmental health》1993,65(1):53-56
Summary The early detection of impaired of vibration sensation is necessary in order to monitor the adverse effects in workers occupationally exposed to neurotoxic chemicals such as acrylamide. The conventional neurological examination which assesses vibration sensation by utilizing a tuning fork is relatively insensitive for this purpose. In the present study, the Vibratron II, a new device for the quantitative measurement of vibration thresholds, was used in 105 healthy Chinese adults. A new testing procedure combining the two-alternative forced-choice procedure and the yes-or-no method-of limits procedure showed good reliability and was less time consuming. The results indicate that significant differences in the vibration threshold of index fingers and great toes were found neither between males and females, nor between the left and the right side. However, there was an age-dependent increase in vibration threshold in nonexposed healthy subjects. The vibration thresholds of 41 workers exposed to acrylamide detected by the Vibratron II were significantly higher than those of the healthy adults in the same age group. The quantitative measurement of vibration threshold seems to be potentially useful for screening peripheral nerve dysfunction in field studies. 相似文献
109.
A. Maître M. Berode A. Perdrix S. Romazini H. Savolainen 《International archives of occupational and environmental health》1993,65(2):97-100
Summary The study validated the use of urinary toluene diamine (TDA) in postshift samples as an indicator of preceding 8-h exposure to toluene diisocyanate (TDI). Nine workers exposed in TDI-based polyurethane foam production were studied. Their exposure levels varied in 8-h time-averaged samples from 9.5 to 94 g/m3. The urinary TDA concentrations varied from 6.5 to 31.7g/g creatinine and they were linearly related to the atmospheric TDI levels. Approximately 20% of TDI is metabolized to diamines but their specificity is remarkable to the extent that by analysis for the 2,4- and 2,6-diamino isomers an idea of the percutaneous absorption may be had. 相似文献
110.
Antonio Mutti Enrico Bergamaschi Sergio Ghittori Marcello Imbriani Innocente Franchini 《International archives of occupational and environmental health》1993,65(Z1):S171-S176
Ambient and biological monitoring of hexane exposure were repeatedly carried out in 14 female shoe makers. Airborne hexane (Ci-H) was measured in 4-h samples collected by a diffusive method. Urinary spot samples were collected before, during (at noon), and at the end of a work shift. 2,5-Hexanedione (2,5HD) in urine collected at noon was poorly related to morning Ci-H. End-of-shift 2,5HD were also poorly related to afternoon air samples. The correlation was still relatively low when end-of-shift 2,5HD was related to 8-h TWA Ci-H (r= 0.44; P<0.01 on=" a=" linear=" scale,=" and=">0.01>r-0.58, P< 0.01=" on=" a=" log-log=" scale).=" end-of-shift=" 2,5hd=" levels=" estimated=" on=" the=" basis=" of=" pre-shift=" values=" using=" a=" mathematical=" model=" were=" much=" higher=" (2.3=" times=" on=" average)=" than=" those=" experimentally=" measured=" during=" the=" study=" period.=" owing=" to=" its=" relatively=" long=" half-time,=" 2,5hd=" seems=" to=" be=" influenced=" not=" only=" by=" current=" exposure,=" but=" also=" by=" hexane=" absorbed=" during=" the=" day(s)=" preceding=" sampling.=" the=" lack=" of=" a=" sampling=" strategy=" may=" account=" not=" only=" for=" inconsistencies=" between=" environmental=" and=" biological=" data,=" but=" also=" for=" a=" possible=" misuse=" of=" biological=" monitoring=" when=" utilized=" for=" risk=" assessment.=" despite=" sometimes=" poor=" correlations=" with=" ci-h,=" 2,5hd=" may=" still=" be=" preferred=" to=" other=" indicators=" as=" a=" marker=" of=" effective=" internal=" dose.=" a=" sampling=" strategy=" should=" ensure=" that=" measured=" values=" are=" representative=" of=" the=" individual=" risk=" for=" adverse="> 相似文献