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141.
Toluene diisocyanate (TDI), a low molecular weight reactive chemical, is known to be a main cause of occupational asthma (OA) in Korea. Although it is thought that inhaled TDI may act as a hapten, the precise mechanisms of TDI-induced OA are unknown. In this study, TDI-human serum albumin (HSA) conjugates (5, 10, 20 and 30 min) were prepared in the range of 1.5 to 5.0 TDI mole/HSA mole. Specific binding of serum IgE to TDI-HSA (30 min) was observed using IgE ELISA as well as ELISA inhibition assay. Around 40% of TDI-induced OA patients were positive for serum specific IgE by ELISA. Degrees of serum IgE binding were different depending on which TDI-HSA conjugate was used as an antigen. Moreover, binding patterns were different depending on the individuals. Interestingly, higher binding of IgE to TDI-HSA (5 min) than to TDI-HSA (30 min) which was more highly substituted was observed in some patients. Probably new antigenic epitopes on carrier proteins were targets of the specific IgE. The results of this study indicated that IgE responses to TDI-HSA conjugates were heterogeneous in TDI-induced OA patients and self-proteins modified by reactive chemicals can become a major target antigen of IgE in certain cases. 相似文献
142.
PCBs with the highest vapor pressures (fewest chlorines) in Aroclors 1016, 1242, 1254 and 1268 were enriched in the vapor phase relative to the original Aroclor during volatilization from a glass surface for up to 8 hr. PCBs with the lowest vapor pressures (most highly chlorinated) were enriched in the corresponding residue. Thus, visual matching of gas chromatograms with those of Aroclor standards may not be sufficient to identify a specific Aroclor since the past history of a sample is often unknown. The enrichment also was detected using isomeric classes, but not using total chlorine content. The perchlorination method and the Webb-McCall method using all chromatographic peaks agreed quantitatively; this was not always so for the NIOSH multiple peaks and the Webb-McCall methods. 相似文献
143.
Mortality among ferrous foundry workers 总被引:8,自引:0,他引:8
M Silverstein N Maizlish R Park B Silverstein L Brodsky F Mirer 《American journal of industrial medicine》1986,10(1):27-43
Mortality analyses were carried out for 278 male hourly workers who were employed for at least 10 years at a gray iron foundry and who died between January 1, 1970 and December 31, 1981. Statistically significant excess proportional mortality due to non-malignant respiratory disease (SPMR = 177), lung cancer (SPMR = 148), and leukemia (SPMR = 284) was found among the 221 white males. Among nonwhite males there was a significant excess in proportional mortality due to circulatory diseases (SPMR = 143). White males in the Finishing classification experienced a significant excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 279) and lung cancer (SPMR = 179). White males in the Core Room classification experienced an excess of proportional mortality due to nonmalignant respiratory disease (SPMR = 321). Case-control studies demonstrated a significant association between nonmalignant respiratory disease and the Finishing classification after controlling for the effects of age, prior occupations in coal mining or foundries, and smoking. A positive but nonsignificant association between lung cancer and Finishing was also found after controlling for age, prior work history, and smoking in case control studies. 相似文献
144.
Gi-Young Park Jong-Min Kim Sung-Il Sohn Im-Hee Shin Michael Y Lee 《Journal of rehabilitation medicine》2007,39(7):526-530
OBJECTIVE: To evaluate the ultrasonographic measurement of shoulder subluxation in patients with post-stroke hemiplegia. DESIGN: Prospective, single blind study. PATIENTS: A total of 41 patients with post-stroke hemiplegia were included (24 men and 17 women, mean age 56 years (standard deviation 11), age range 34-78 years). METHODS: Clinical evaluation of the affected shoulder was assessed using the Motricity Index scores and the Modified Ashworth Scale. Two ultrasonographic measurements were taken to check intra-rater reliability. The shoulder subluxation ratio was determined as the ratio of the radiographic vertical and horizontal distance, and the ultrasonographic lateral and anterior distances in the affected shoulder divided by that in the unaffected shoulder. RESULTS: Intraclass correlation coefficients of the repeated ultrasonographic lateral/anterior distance measurements in the unaffected and affected shoulders were 0.979/0.969 and 0.950/0.947, respectively. Ultrasonographic lateral/anterior distance ratios were negatively correlated with Motricity Index scores of the affected shoulder abduction (r = -0.490, p < 0.001/ r = -0.671, p < 0.001). Ultrasonographic anterior distance ratio was negatively correlated with Modified Ashworth Scale score of the affected shoulder (r = -0.374, p < 0.05). However, there was no correlation between radiographic distance ratios and clinical evaluation scores. CONCLUSION: We strongly recommend ultrasonography as a diagnostic tool to measure the degree of shoulder subluxation in patients with post-stroke hemiplegia. 相似文献
145.
单独一种维生素缺乏对免疫功能的影响已有较多研究报道,但维生素缺乏一般不会单独发生,为此本实验研究了维生素A、E、B_2、B_6及叶酸供给不足(1/3生理需要量)、加倍补充(2倍和3倍生理需要量)后对小鼠抗体形成细胞的复合效应。动物喂养6周(不足纠正组喂8周),结果显示,不足组抗体形成细胞显著低于对照组,而2倍、3倍组则显著升高,不足组补充正常量维生素后,抗体形成细胞升高超过对照组,与2倍量组无显著差异;另外,该几种维生素对肝脏RNA、脾脏DNA、RNA及肝脏蛋白质均有明显影响,且抗体形成细胞的变化与核酸、蛋白质含量改变相平行,提示后者可能是维生素作用于体液免疫系统的生化机制。 相似文献
146.
147.
磺胺噻二嗪硫酮衍生物的合成及其抑菌活性 总被引:1,自引:0,他引:1
利用药物化学骈合原理设计并合成了一系列新的3,5-二取代1,3,5-噻二嗪-2-硫酮类化合物,其结构经红外光谱,紫外光谱及元素分析证实,抑菌活性试验显示了良好的抑菌活性。 相似文献
148.
用国产恩威牌洁尔阴对阴道常见七种细菌进行抑菌试验,结果该药对其中五种细菌有明显抑菌作用,本文为洁尔阴治疗细菌性阴道炎提供了实验依据。 相似文献
149.
We studied the effect of the 5-HT1A receptor antagonist, pindolol, on the prolactin (PRL) response to the 5-HT releasing agent,d-fenfluramine (d-FEN), in ten healthy male volunteers. Pindolol pretreatment lowered baseline PRL levels but, when this effect was taken into account, did not significantly attenuate the PRL response tod-FEN. Within the limitations that attend the use of pindolol as a 5-HT1A receptor antagonist, the data suggest that although 5-HT1A receptors may play a role in the tonic release of PRL, they are not involved in the release of PRL produced byd-FEN. We propose that the PRL response tod-FEN may involve selective activation of postsynaptic 5-HT2 receptors. 相似文献
150.
Jung-Won Park Joo-Young Yang Cheol-Woo Kim Kyu-Sang Kim Chein-Soo Hong 《Annals of allergy, asthma & immunology》2006,97(4):551-556
BACKGROUND: Previous studies reported that early diagnosis and avoidance therapy are the most important factors for prevention of permanent lung impairment; however, few studies have evaluated the long-term prognosis of reactive dye-induced occupational asthma (RD-OA). OBJECTIVE: To evaluate the long-term outcomes of RD-OA. METHODS: Methacholine airway hyperresponsiveness (AHR) and lung functions were evaluated and compared in 26 patients with RD-OA at the time of diagnosis and after complete avoidance of the causative agents. Patients with continued (n = 13) or remitted (n = 6) AHR were further monitored for up to a mean +/- SD of 8.7 +/- 1.8 years. RESULTS: The AHR resolved in 10 (38%) of 26 patients a mean +/- SD of 2.2 +/- 1.3 years after complete avoidance of RDs; however, prebronchodilator forced expiratory volume in 1 second (FEV1) values were not different. Levels of IgE specific to the RD-human serum albumin complex were markedly decreased at first follow-up in 5 RD-atopic patients from whom paired serum samples were compared (P = .02). The AHR disappeared in an additional 5 patients and improved in 4 by the second follow-up. The FEV1 values also improved compared with diagnosis and first follow-up levels. Favorable prognosis was associated with early diagnosis of RD-OA and complete avoidance of the causative agent. No association was found with smoking history, latent periods, the presence of RD specific IgE, baseline provocation concentration that caused a decrease in FEV1 of 20%, or FEV1. CONCLUSIONS: Early diagnosis and avoidance therapy are the most important prognostic factors in RD-OA. The AHR and lung function of patients with RD-OA can sometimes be recovered steadily and slowly through avoidance measures. 相似文献