天然钍对作业工人健康影响的研究

为研究包钢的原料中所含天然钍对作业工人健康的影响，对５９８５人的暴露队列进行了１７年的流行病学调查。结果发现，作业工人外周血淋巴细胞染色体畸变率随年附加有效剂量的增加而升高（与对照组比较Ｐ＜０．０１）。工龄为５～１４年者增加较快，１５年后增加缓慢，趋于平衡。尘肺分析结果提示，天然钍可能增强ＳｉＯ２的致肺纤维化作用。肿瘤死亡率除胃癌外，其余ＲＲ均大于１，但无统计学意义。相距一年的两次植物血球凝集素（ＰＨＡ）皮试反应均有增强，但外周血淋巴细胞离体照射后，染色体畸变未见适应性。女工妊娠期从事钍作业，其所生子女的智力发育无明显异常。     

Image-directed color Doppler ultrasonography in the evaluation of superficial solid tumors

Image-directed color Doppler ultrasonography (ICDUS) studies of 86 patients with superficial solid masses yielded significantly lower resistive index (RI) values in acute inflammatory lesions, but no significant difference between the maximum systolic flow velocities (S) of the patient groups with malignant, benign, and acute inflammatory lesions. When analyzed separately, the malignant soft-tissue tumor subgroup was shown to have significantly higher mean RI compared to that of the malignant node subgroup. We conclude that RI may be useful in the differentiation of acute inflammatory masses from other pathological entities. Malignant soft-tissue tumors, especially sarcomas, may have different Doppler features from those of carcinomatous tumors. © 1995 John Wiley & Sons, Inc.     

Modulation of ryanodine-induced contractures in human skeletal muscle pretreated with dantrolene

Dantrolene seems to be the causal therapy in malignant hyperthermia (MH) crisis but the complex mechanisms of MH and dantrolene therapy are still not fully understood. The influence of dantrolene on ryanodine-induced contractures has been reported in animal studies only. In the present study 20 patients from] 7 families were tested for MH using the protocol of the European Malignant Hyperthermia Group. In addition ryanodine-induced contractures were evaluated following bolus application of 10.0 μmol · 1^-1 ryanodine. After pretreatment with 1 μimol · 1^-1 dantrolene ryanodine-provoked contractures developed significantly later in MHS (15.8±1.8 min) and MHN (46.0±4.2 min) muscle specimens than after ryanodine alone (MHS 4.8±0.7 min), (MHN 13.7±0.9 min). They were no longer observed in either group after pretreatment with 5 μimol · 1^-1 dantrolene. We conclude that dantrolene is able to attenuate ryanodine-induced contractures dose-dependendy, and therefore it is speculated that dantrolene could specifically act at the ryanodine receptor binding site.