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Biomedical subjects

Q T Pham

Publications and source records attributed to Q T Pham.

At least 73 records · Page 4Linked to original sources
PubMed1984

Prognostic value of acetylcholine challenge test: a prospective study.

Eleven hundred and nine iron mine workers aged 35 to 55 with normal chest radiographs were submitted to a pulmonary examination consisting of a questionnaire, a clinical examination, and pulmonary function testing including an acetylcholine challenge test. A positive response (decrease of FEV1 of more than 10%) was observed in 210 subjects (Ace+). The remaining 899 had a negative response (Ace-). Bronchitis, asthma, dyspnoea, and obstructive syndrome were more frequent in the Ace+ group. Five years later, 820 subjects were reexamined: occasional cough and sputum and chronic bronchitis appeared more frequently among subjects without symptoms at the first examination but with a positive acetylcholine challenge test. The obstructive syndrome was more often observed and regressed more rarely in the Ace+ group. The results confirm the use of a test of bronchial hyperreactivity as a means of identifying subjects at risk from chronic obstructive lung disease.

Acetylcholine↗
PubMed1984

Reduction of pulmonary function indices: comparison of two hierarchical methods.

From tests for evaluating pulmonary function many indices may be calculated. In order to reduce their redundancy, two hierarchical methods for selecting the most significant indices are applied to data collected on a group of 228 firemen. The first method consists in a stepwise linear discriminant analysis which selects the indices according to their discriminant value for distinguishing between asymptomatic and symptomatic subjects. The second one is derived from a stepwise multiple correlation procedure, which selects the indices on the basis of their linear relationships. These two methods lead to different results and the choice between them should be made according to the aims intended for data reduction.

Adult↗
PubMed1984

[Quality control of spirographic examinations in a health center].

A quality control of spirographic examinations in a health centre was carried out by repeating, after a fortnight's interval, measures of vital capacity (CV) and FEV1 (VEMS) in 629 subject of both sexes, aged 18 to 62. Water spirometers were used and their cylinders were regularly calibrated. The first series of spirographic measurements were made during a routine health check (which included other examinations) by 7 technicians who usually do the work, while the second series of measurements was made of fortnight later by the most experienced three. The overall mean values show a significant difference for vital capacity between the first and second measurement; this difference was so for young male subjects (less than 30 years). The scatter was greater for subjects over 50 years of age. The varied results observed for the same subjects obtained by two different technicians, or the same technician, underlines the fact that the scatter of the results depends largely on the technician even though spirographic tests are classically considered easy to perform.

Adolescent↗
PubMed1983

[Study of the pulmonary function of arc welders. Results of a study in an industrial vehicle production plant].

Pulmonary examinations (i.e. clinical, functional and radiological) were conducted on 76 arc welders from an industrial vehicle production plant and on 74 'controls' from the same plant. Arc welders were exposed for an average of 11 years to welding gases and fumes; controls were not welders and were not exposed to any identifiable professional risk of pulmonary disease. There is no significant difference between these two groups concerning clinical, functional and radiological findings; but the prevalence of pulmonary abnormalities (whatever their type or their intensity) is high in the two groups (60%). This survey does not show any particular risk of pulmonary disease among the arc welders working in this plant. However, complementary studies in other industrial areas are required to investigate possible risks due to other arc-welding processes and other working conditions.

Adult↗
PubMed1983

Incidence of lung cancer among iron miners.

A study has been performed using 5300 iron miners from Lorraine (France) with ages ranging from 35 to 55 years, who were working, and had a normal chest radiography. 1173 workers were chosen randomly and given the following examinations: questionnaire, clinical examination and function tests (VC, FEV1, residual volume (RV), acetylcholine test, carbon monoxide steady-state test). This group of 1173 was followed for 5 years. 40 died and the exact causes of death were known. 13 had lung cancer, which is more than three times the number expected in the French male population of the same ages. All subjects who died from lung cancer were underground miners and, at the first examination, had a higher incidence of bronchitis and more functional defects than both the 27 who died from other causes and the underground miner group as a whole. The excess mortality due to lung cancer is discussed with regard to noxious agents that were measured (radioactivity, which was rather low, total and respirable dusts, Nox, CO) and with regard to both the work environment and duration of work.

Adult↗
PubMed1981

[Variability of respiratory function tests 9 weeks observation (author's transl)].

42 normal male subjects from 19 to 27 years, are examined in conditions of field studies once a week for 9 weeks. At each session are measured: flow volume curves with determination of vital capacity (VC), forced expiratory volume in one second (FEV 1.0), peak flow (V peak), flows at 0.75, 0.50, 0.25 of VC (V 0.75 VC, V 0.50 VC, V 0.25 VC). Single breath nitrogen test, with determination of slope of phase III (delta N2/liter) and closing volume/vital capacity (CV/VC). Single breath and steady state tests with carbon monoxide. Variability of functional pulmonary indices in this study is greater than those observed in the literature during shorter period of term. Some indices varied significantly during these 9 weeks of observation like V 0.25 CV, indices of transfer factor of CO and CV/VC (according to repetition of test or meteorologic factors?). Relevance of studying variations during a relatively long period, is pointed out in interpretation of results observed in prospective studies.

Adult↗
PubMed1980

[The different ways of expressing the results of the monoxide test in steady state: discussion and proposition of reference values for epidemiological studies (author's transl)].

The results of the steady state carbon monoxide test can be expressed quantitatively as the amount of CO absorbed by the lung per minute and per 1 mm Hg pressure difference (TCO; ml/min/mm Hg) or as the ratios between partial pressures of CO (FICO, FECO, FACO), fractional untake coefficient (Formula: see text), From measurements taken in 141 non-smokers (mean age 47.43 +/- 6.4 years), 60 ex smokers (mean age 45.73 +/- 5.29 years) and 322 smokers (mean age 46.65 +/- 5.5 years), TCO and fractional uptakes were calculated and discussed. Considering the fact that mean TCO had a larger standard deviation that mean FUCO and that TCO had a non-Gaussian distribution, the authors chose to express the results of the test in fractional uptakes. Equations are proposed to calculated fractional uptakes.

Adult↗
PubMed1978

Respiratory manifestations and skin reactivity in the detergent industry.

Workers at two continental European enzyme detergent plants were examined to determine respiratory symptomatology, pulmonary function abnormalities and skin reactivity to four enzymes through use of a standardized questionnaire, flow-volume curves and provocative acetylcholine, single breath carbon monoxide, and prick tests. In both plants, the frequency of bronchitis was similar but the frequency of asthmatic or rhinopharyngitic symptoms was different. Symptomatology was more frequent in female detergent workers than among the clerical staff but no difference among men in different jobs was noted. Very few spirometric abnormalities were observed but bronchial hyperactivity was more frequent in packaging and warehouse workers. No correlation between DLco/AV and of work or skin reactivity was found. Skin reactivity (about 10% in both plants) and duration of employment were not related to symptomatology nor functional abnormalities.

Adolescent↗
PubMed1978

[Prevalence of bronchitis in socio-professional groups. III. Unexposed workers (author's transl)].

Besides the two groups of exposed workers (building workers and workers of a steel mill), a reference group of age-matched (40--60 years) unexposed workers was studied. They were examined by the same procedures (interrogation by ESC questionnaire, vital capacity, forced expiratory volume in 1 sec residual volume, apnea CO test and steady-state Co test at rest and exercise of 40 W. Results are presented according to age and smoking habits. They are compared with results observed in the two exposed groups, and discussed.

Adult↗
PubMed1977

[Long term effects of low concentrations of noxious gases on the respiratory system: results of an epidemiological study among iron mines workers in Lorraine (France). (author's transl)].

An epidemiological study of 1,178 iron-mine workers in the Lorraine basin was conducted in order to assess the long-term effects on the respiratory system of low concentrations of noxious gases produced by the machinery and explosives in use. The subjects were selected at random from 5,300 workers who were aged between 35 and 55, had been in the mines for at least five years and who were free from radiological abnormalities such as siderosis, tuberculosis, fractured ribs, etc. For each subject a standard questionnaire (E.C.S.C. bronchitis/emphysema questionnaire) was completed and a clinical examination was performed along with the following tests-vital capacity; forced expiratory volume in 1 second; residual volume; acetylcholine test; steady state CO test for calculation of total and partial transfer functions. A venous blood sample for the determination of blood CO was taken as the subject left his place of work.

Adult↗