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Clinical, immunological, and intestinal studies on 26 children with IgA deficiency in the age range 2 to 16 years are reported. 9 of these children were suffering from autoimmune disease, namely thyroiditis (5), thyrotoxicosis (1), rheumatoid arthritis (2), and probable Sjögren''s syndrome (1). The last-mentioned patient had defective cellular immunity. Altogether 11 patients were subject to recurrent respiratory tract infections. The symptomatology of the remaining patients was variable. In a boy with growth retardation, a chromosome anomaly was found, and endocrinological studies indicated total absence of growth hormone.In 21 patients IgA was undetectable, while 5 had trace amounts of IgA in their sera. IgG was raised in 11 patients, and one patient had low serum IgG. IgM levels were mostly normal. Precipitating antibodies to cow''s milk proteins were present in all but one serum.Small intestinal biopsy was performed on all patients. In 3 cases total villous atrophy was detected and these probably had coeliac disease, though malabsorption symptoms were not always evident. Disaccharidase assay of biopsy specimens revealed 2 cases of isolated lactase deficiency among 8 tested.Results show that the increased incidence of autoimmune disease reported in IgA deficiency in adults also holds true in children; i.e. that there is a raised incidence of coeliac disease with or without symptoms in IgA deficiency.  相似文献   
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Objectives:To estimate the joint effects of infections with human papillomavirus type 16 (HPV16) and Chlamydia trachomatis and smoking on the risk of cervical cancer. To study whether the joint effects can be accounted for by misclassification in the HPV serology. Methods:A nested case–control study with incidence density sampling was conducted in three cohorts of 530,000 women, who donated serum samples to three Nordic serum banks in 1973–1994. The main outcome measure is the odds ratio (OR) of incidence rates of invasive cervical squamous cell carcinoma (SCC) among those seropositive for HPV16 and/or C. trachomatis and/or with increased levels of cotinine in serum compared to those negative for all the three exposures. Results:Two hundred eight women with SCC and 624 matched controls were identified during a mean follow-up of 5 years through linkage to the national cancer registries. Exposure to past infections and smoking was defined by presence of specific IgG antibodies to HPV16 and C. trachomatis and increased levels of serum cotinine. Observed ORs were compared to OR = 20 for HPV16 and accounting the differences for by misclassification bias. OR = 20 was elected as a gold standard on the basis of other studies with PCR-based analyses and a follow-up design. Each of the three exposures was associated with an increased risk of SCC (OR = 5.4 for HPV16, 3.4 for C. trachomatis and 1.8 for cotinine). The interaction was antagonistic (observed OR = 2.5 among those positive for all three exposures as compared to OR = 33 expected on the basis of multiplicative single effects (p = 0.047)). The antagonism could not totally be accounted for by any credible combination of sensitivity and specificity of HPV16 serology. Conclusion:HPV16, C. trachomatis, and smoking are likely to be risk factors of SCC with strong antagonistic joint effect. Non-differential misclassification in serology for HPV16 could be ruled out (but only some types of differential) as an alternative explanation for the observed antagonism.  相似文献   
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In rats adapted to a +30°C temperature for one week, transfer to a temperature of +4°C increased immunoassayable serum TSH from 150–300 ng/ml 800–2000 ng/ml in 30 min. Since this response, as well as the level of serum TSH without stimulation, were decreased by reserpine, phentolamine, phenoxybenzamine, disulfiram and diethyldithiocarbamate, noradrenaline may be involved in the stimulation of TSH secretion. TRH-induced TSH increase was not blocked by reserpine.

1-Dopa, a noradrenaline precursor, decreased the TSH response to cold; -methyl-p-tyrosine increased the TSH level. Apomorphine decreased the level of serum TSH and inhibited the response to cold. The possibility of a dopaminergic inhibitory factor released from the hypothalamus is discussed. 5-HT has possibly a role in the acetylcholine is involved.  相似文献   

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OBJECTIVES: The aim of the study was to determine the causes of impairment of ventilatory function and diffusing capacity in smoking asbestos-exposed workers (N=590) showing radiological pleural thickenings or pulmonary fibrosis. METHODS: High-resolution computed tomography (HRCT) and spirometry were performed, and diffusing capacity was measured. The workers were divided into five groups based on the HRCT scoring: pleural disease (N=190), pulmonary fibrosis (N=68), emphysema (N=148), combined fibrosis and emphysema (N=74), and marked adhesions (N=110). The graded lung function impairment was compared between the groups. RESULTS: Moderate impairment of forced expiratory volume in 1 second [odds ratio (OR) 2.72, 95% confidence interval (95% CI) 1.31-5.57] and forced vital capacity (OR 2.81, 95% CI 1.05-6.89) was associated with the persons with combined fibrosis and emphysema. Marked impairment of diffusing capacity was associated with the combined fibrosis and emphysema (OR 4.94, 95% CI 2.48-9.77) but not with pleural disease (OR 0.21, 95% CI 0.09-0.45) or pulmonary fibrosis (OR 0.36, 95% CI 0.08-1.05). For the persons with combined fibrosis and emphysema, the mean fibrosis score did not differ between normal, slightly reduced, or markedly reduced diffusing capacity, but the emphysema score was significantly higher for the patients with marked impairment than for those with normal diffusing capacity (P < 0.01). CONCLUSIONS: Different profiles of asbestos- and smoking-induced pulmonary or pleural disease were found. The results indicate that the most important factor determining the degree of functional impairment in smoking asbestos-exposed workers is the presence of pulmonary emphysema.  相似文献   
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Introduction Antegrade intramedullary (IM) nailing of humeral shaft fractures is reported to cause shoulder joint impairment. This retrospective study compared shoulder joint symptoms, range of motion (ROM), and isometric strength after antegrade IM nailing and dynamic compression (DC) plating of humeral shaft fractures.Materials and methods We compared 29 patients with DC plating and 44 with antegrade IM nailing of their humeral shaft fractures. Shoulder pain, LInsalata and Constant scores, shoulder joint ROM and isometric shoulder strengths were measured after mean follow-up of 6.2 (1–15) years (DC plating) and 5.5 (2–10) years (IM nailing).Results Patients had nonsignificantly more shoulder pain after IM nailing than after DC plating. Shoulder scores and isometric strength measurements showed no difference between the groups. Flexion was significantly better after DC plating, but none of the other ROM parameters differed between the groups. The shoulder scores and all ROM and strength parameters of the injured side were significantly lower than on the uninjured side in both groups.Conclusions Shoulder joint ROM and strength does not recover to normal after humeral shaft fracture. Antegrade IM nailing if performed properly is not responsible for shoulder joint impairment.  相似文献   
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