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961.
962.
963.
964.
Evolution of bronchial reactivity was examined in a sample of aluminium potroom workers exposed to a variety of respiratory irritants in concentrations below the MAC values for Yugoslavia (hydrogen fluoride, particulate fluorides, sulphur dioxide). Lung function indices and bronchial reactivity were measured in 24 workers continuously employed in an aluminium plant and in nine workers who had ceased to work in the plant. Measurements took place over a two-year interval. A sustained level of bronchial reactivity was recorded in both examined groups regardless of occupational practice. Even in workers with dyspnoea and airway obstruction bronchial reactivity did not worsen in spite of continuous exposure. Avoidance of exposure to potroom fumes did not bring about any significant improvement of reactivity, moreover, bronchial reactivity deteriorated in one worker. Owing to discordance between spirometric values and bronchial reactivity, a follow-up of workers removed from harmful occupational exposure is suggested. 相似文献
965.
Renal disease in a patient with hereditary complete deficiency of the fourth component of complement
Hereditary complete deficiency of the fourth component of complement (C4) is an extremely rare disorder with 17 cases reported so far. Twelve of these patients suffered from a systemic-lupus-erythematosus-like illness. The patient we here describe presented with severe Henoch-Sch?nlein purpura (HSP) at the age of 17. Immunofluorescence of a kidney biopsy showed granular deposits of IgG, IgA, IgM, C3 and fibrinogen in the mesangium and segmentally along the basement membrane. Six years later, the patient developed hypertension and nephrotic syndrome. Renal function deteriorated rapidly. He was on hemodialysis for 12 months and then received a cadaveric kidney graft. After 2 years of uncomplicated course, microhematuria and proteinuria developed. Immunofluorescence of a transplant biopsy was virtually identical to the pattern in the patient's own kidneys. We thus conclude that the patient had recurrence of his primary disease in the graft. Three and a half years after transplantation hemodialysis had to be restarted. This unique case supports the current view that deficiency of classical pathway components predisposes to the development of immune complex diseases and that the complement system is activated via the alternate pathway in HSP. Furthermore, we assume that complete C4 deficiency was the major cause for the recurrence and unfavorable outcome of HSP in the graft. 相似文献
966.
967.
V P Podzolkov N A Kiselev L R Plotnikova L M Zotova L V Petrunina I N Mitina S V Kirakosian V I Mironenko L V Za?tsev I A Iurlov 《Grudnaia i serdechno-sosudistaia khirurgiia / Ministerstvo zdravookhraneniia SSSR [i] Vsesoiuznoe nauchnoe obshchestvo khirurgov》1990,(9):15-21
The article deals with the results of complex study of the effect of pulmonary insufficiency on intracardiac hemodynamics and function of the heart in the immediate and late-term periods after radical correction of Fallot's tetralogy. Answers are also given to questions concerning the expediency of the use and functional adequacy of a xeno-pericardial monocusp in the closure mechanism of the pulmonary artery valve. The study showed that massive pulmonary regurgitation has a negative effect on the functional condition of the right ventricle in late-term postoperative periods. Convincing data were obtained which allow a graft with a monocusp of a bull's pericardium to be recommended for further clinical use to prevent insufficiency of the pulmonary artery valve after radical correction of Fallot's tetralogy. 相似文献
968.
O Reiker?s 《Acta orthopaedica Scandinavica》1990,61(4):319-320
A patellar brace with a lateral pad was used in 25 patients with unilateral retropatellar pain syndrome. The patients were told to use the brace in activities that loaded the patella, and they were followed for 1 to 2 years. At follow-up, 8 patients were improved, while the symptoms were unchanged or worse in 17. The level of activity was increased in 4 patients, reduced in 3, and unchanged in the others. It is concluded that treatment with a patellar brace with a lateral pad is not likely to succeed in the majority of patients with retropatellar pain syndrome. 相似文献
969.
I Skare T Bergstr?m A Engqvist J A Weiner 《Scandinavian journal of work, environment & health》1990,16(5):340-347
Mercury exposure was studied among dental personnel with the use of urinary mercury excretion rates and questionnaires. The study covered 314 dentists and dental nurses employed in public clinics and private practices in Stockholm. The obtained urinary mercury excretion rates were analyzed by stepwise regression for assigning them to different origins, such as environmental factors, number of amalgam surfaces, chewing of gum, kind of employment and profession, age, sex, amalgam handling time, and use of amalgam capsules. On the average the occupational contribution to the total urinary mercury excretion rate was small and of the same order as the contribution from their own amalgam fillings (approximately 2 micrograms of mercury/24 h). There were, however, individuals showing excretion rates close to the levels at which effects on the central nervous system and the kidneys have been reported. 相似文献
970.