ISSN:0271-3586    

DOI:10.1002/ajim.4700020202

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractExposure of mice to vanadium caused a dose‐related but nonsignificant decrease in the antibody‐forming cells in the spleen of animals challenged with sheep erythrocytes. Delayed hypersensitivity reaction was not affected in similarly sensitized animals. Serum immunoglobulins were also not altered by the vanadium treatment. Splenic lymphocytes obtained at 1, 4, 8, and 13 wk of exposure to 0, 1, 10, and 50 mg of vanadium per liter of drinking water showed an increased DNA synthesis related to vanadium treatment when cultured in the presence of phytohemagglutinin and pokeweed mitogen but not with bacterial lipopolysaccharide. Addition of vanadium to splenic cultures in vitro caused a marked enhancement of lymphocyte transformation at low concentrations, whereas a decreased cellular proliferation was observed at high concentrations of vanad

ISSN:0271-3586    

DOI:10.1002/ajim.4700020203

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractAn unusual case of silicosis is described in a worker who inhaled the dust of pure silica while working in a sandstone quarry. The exposure lasted only eight years. In 1980, 45 years after exposure ceased, severe clinical manifestations of silicosis appeared for the first time. The chest X‐ray showed a pneumoconiosis A 2mn/A2 Mn Cor, em, hilus, based on the International Classification of Geneva, 1958. A diagnosis of sandstone pneumoconiosis was made. The case is one further example of late‐occurring disease appearing after a latency of several deca

ISSN:0271-3586    

DOI:10.1002/ajim.4700020204

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractBoth subcutaneous and hepatic hemangiosarcomas were induced in mice exposed to vinyl chloride monomer, and for the first time, the ultrastructure of hemangiosarcomas related to vinyl chloride exposure has been described. The subcutaneous hemangiosarcoma developed in a mouse's ear 29 weeks after exposure to 10 ppm vinyl chloride for 4 weeks, and the hepatic hemangiosarcoma was found in a mouse's liver at necropsy 56 weeks after exposure to 600 ppm vinyl chloride for 4 weeks. Both tumors showed a localized, cystic nodular appearance with a dark red tone. Histologically, an angiomatous architecture, the presence of neoplastic mesenchymal cell aggregates, focal necrosis, and hemorrhagic foci were common. Ultrastructurally, two neoplastic cell types, a mesenchymal and a well‐differentiated endothelial cell type, were identified in both tumors. In addition, in the hepatic tumor, a pericyte‐like neoplastic cell was also present. The incidence of hemangiosarcoma was much lower than that of lung tumors (alveologenic tumor) in mice exposed to vinyl chloride at the same concentrations for the same duration. This study suggests that there is no basic difference in ultrastructure between the vinyl chloride‐induced hemangiosarcomas and hemangiosarcomas not related to this chemical exp

ISSN:0271-3586    

DOI:10.1002/ajim.4700020205

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractDeterminations of benzene concentration in blood and of phenol in urine were made by head‐space gas chromatography techniques on samples taken near the end of the work day from two groups of workers potentially exposed to low levels of benzene in the work‐place atmosphere. Preliminary results suggest that benzene in blood is more reliable than phenol tests for assessing both exposure and uptake of benzene. Normal values of phenol in urine (10 mg/liter or less) were found in nearly all those cases in which benzene was detected in the bl

ISSN:0271-3586    

DOI:10.1002/ajim.4700020206

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractMultiphasic health testing (MHT) is often offered to populations of workers usually with the objective of identifying individuals who may be ill. Results are typically not analyzed in relation to estimates of workplace exposure. We describe the results of combining MHT with industrial hygiene assessment of workplace exposures as a method of identifying possible health hazards rather than merely potentially ill individuals. MHT was offered to all production and maintenance workers employed at a tire manufacturing plant. Of 954, 744 participated. We measured worker exposure to respirable particulates, solvent vapor, and noise. We computed the frequency of positive screens among workers classified by exposure and compared these frequencies with expected values adjusted for confounding variables including age, sex, race, and smoking and drinking habits. Workers exposed to higher concentrations of respirable particulates exhibited signs of respiratory and gastrointestinal morbidity. Workers exposed to emissions from heated, uncured rubber undergoing plastic deformation reported chest tightness on return to work. We conclude that combining MHT with assessment of workplace exposure is a valid method for identifying possible occupational health hazards.

ISSN:0271-3586    

DOI:10.1002/ajim.4700020207

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractMultiphasic health testing was provided to 744 rubber workers at a tire manufacturing plant. Sixty‐two white males from this population had worked longest in the curing department. Personal exposure to respirable particulates was measured for curing press operators. Outcome on screening tests for curing workers was compared with that of 280 white males at this same plant who had never worked in departments known to include jobs where they could have been exposed to respiratory health hazards. Employment in the curing department is associated with shortness of breath, chest tightness, wheeze, loss of FEV‐1 and FVC, decline of FEV‐1/FVC, and tingling and numbness in the extremities. These associations are stronger with increased duration of employment in the curing department. This paper further demonstrates the potential for using multiphasic health testing combined with measurements of workplace exposure for identifying occupational health ha

ISSN:0271-3586    

DOI:10.1002/ajim.4700020208

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractThe present study examines whether VCM or one of its metabolites, chloracetaldehyde, has a short‐term effect on cell metabolism. ATP, ADP, and AMP levels were measured in regenerating rat liver after 4 and 16 hours. No change in the levels of these nucleotides was evident after i.v. injection of VCM immediately after partial hepatectomy. A second technique, that of measuring transmembrane potentials with microelectrodes, was applied both to cells in rat liver slices and pulmonary alveolar macrophages. The addition of VCM and chloracetaldehyde with the electrodes in position in rat liver slices had no significant effect on transmembrane potentials. The same was true for a series of measurements on macrophages before and after addition of the test chemicals. It therefore appears that VCM does not alter general cell metabolism but could act on a specific intracellular targe

ISSN:0271-3586    

DOI:10.1002/ajim.4700020209

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractA study of workers exposed to low levels of lead as impurities in aluminum (as low as 0.07%) shows a statistically significant difference in blood and urine lead levels as compared with a control group. In addition, alterations in precursors of heme were demonstrated as reflected in elevated levels of urinary delta‐aminolevulinic acid and erythrocyte protoporphyrin IX. This study has implications for workers who are exposed to metals with low concentrations of lead (less than 1%) since this exposure tends to go unnoticed both by the workers, even when symptoms are present, and by physicians who ignore or discard signs of lead intoxication because they relate the occupational exposure of the workers to other metals, not directly to lea

ISSN:0271-3586    

DOI:10.1002/ajim.4700020210

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY

摘要:

AbstractPulmonary circulation hemodynamics was studied by microcatheterization at rest and during exercise in 16 workers with asbestosis. There was pulmonary arterial hypertension owing to increased total pulmonary resistance even in the early stages of pneumoconiosis, sometimes without impairment of lung function. In two cases, a partial reduction in pulmonary hypertension and total pulmonary resistance was obtained with aminophylline. The pathogenesis of pulmonary circulation impairment has been attributed in previous work to periarteriolar fibrosis originating in the lymphatic vessels, until now insufficiently emphasized as the anatomical basis of these physiological alterations.

ISSN:0271-3586    

DOI:10.1002/ajim.4700020211

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1981

数据来源: WILEY