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991.
San-Chi Lin Chung-Chieh Tai Chang-Chuan Chan Jung-Der Wang 《American journal of industrial medicine》1994,26(2):221-228
A chromium electroplating worker, suffering from epistaxis during work, was found to have nasal septum perforation. To determine the etiology and prevalence of nasal septum lesions, we conducted a survey of seven chromium electroplating factories and examined 79 workers. Forty workers from three aluminum electroplating factories were also enrolled as the reference group. Subjects were thoroughly examined by an otolaryngologist and each of them provided a blood and urine sample. A questionnaire interview regarding symptoms of the upper respiratory tract, past medical history, life style, and work history was also conducted. Air chromium concentrations were measured by taking area samples for 4–6 hours. Based on field observation and chromium measurements, we divided chromium electroplating into three different exposure zones: workers directly dealing with electroplating tanks (n = 31), other process workers (n = 29), and office workers and drivers (n = 19). Among the 79 chromium electroplating workers, there were 16 cases of nasal septum perforation, and 42 with either scar formation or ulceration; 10 chromium electroplating workers developed skin ulcers after performing chrome plating. No workers from aluminum electroplating factories had any nasal septum or skin abnormalities. There was a consistent trend between the degree of chromium exposure and the signs and symptoms related to the nose, throat, and skin. Immediate improvement of occupational hygiene is warranted. 相似文献
992.
浆细胞病患者IL-4产生细胞数减少的意义及机制探讨 总被引:2,自引:0,他引:2
本文运用APAAP法检测了16名浆细胞患者外周血细胞在PHA刺激下产生IL-4的能力。发现浆细胞病组阳性细胞比率明显低于正常对照组(P<0.001),且阳性细胞比率与患者血清中多克隆IgM、IgA水平呈正相关(r=0.806和r=0.703)。在正常人外周血中加入CRP50mg/L,经PHA刺激后IL-4产生细胞也明显减少。作者假设,由于IL-6增高引起CRP等急性期相蛋白大量分泌,使IL-4产生受到明显抑制,从而使B细胞激活发生障碍是浆细胞病中多克隆免疫球蛋白合成抑制的主要原因。 相似文献
993.
The effects of radiofrequency catheter ablation on the metabolic enzymes and Ca++-ATPase of myocytes
Summary Using histochemical technique, the effects of radiofrequency catheter ablation (RFCA) on the activities of LDH, SDH, CCO,
and Ca++-ATPase of guinea-pig ventricular myocytes were examined. The histological changes were observed for comparison. Radiofrequency
energy (500 kHz) delivered was 20 WX 10 s. The results were as follows: RFCA resulted in significant impairments in all the
four kinds of enzymes but without statistical differences in the areas involved in this energy level. No statistically significant
difference was found between the ranges of enzymatic damages and areas of pathological lesions. These findings showed a consistency
in areas of the histological and histochemical lesions resulted from RFCA. 相似文献
994.
ImmunoadjuvantactionofliposomesforentrappedJapaneseEncephalitisvirusE-glucoprotein¥HuJun(胡军);MaWenyu(马文煜);HuangQingsheng(黄庆生)... 相似文献
995.
Shuu-Jiun Wang Kwong-Kum Liao Hung-Hsiang Liou Shei-Shee Lee Ching-Piao Tsai Kon-Ping Lin Ko-Pei Kao Zin-An Wu 《Muscle & nerve》1994,17(4):411-418
Sympathetic skin response (SSR) and R–R interval variation (RRIV) were studied in 36 chronic, nondiabetic uremics to compare with their nerve conduction studies (NCS) and clinical dysautonomia. Abnormal SSR was noted in 5 (13.9%) patients, abnormal RRIV in 14 (38.9%), and abnormal NCS in 26 (72.2%). The patients were classified into three groups: group (GP) 1: “normal,” n = 21 (58.3%), normal RRIV and SSR; GP 2: “isolated parasympathetic dysfunction,” n = 10 (27.8%), abnormal RRIV and normal SSR; and GP 3: “sympathetic sudomotor dysfunction,” n = 5 (13.9%), abnormal SSR. A significant difference in age was found among the three groups (GP 3 > GP 2 > GP 1; P < 0.0001, ANOVA). After controlling the age factor, we still noted a tendency toward increasing NCS disturbances (distal latency and nerve conduction velocity of peroneal nerve; P < 0.05, multiple regression analysis) and frequencies of clinical autonomic symptoms (postural dizziness and impotence; P < 0.05, Mantel–Hanszel test) from GP 1 to GP 3. Patients with abnormal SSR (GP 3) displayed significantly higher frequencies of postural dizziness and impotence, indicating the relationship between an absence of SSR and clinical dysautonomia. © 1994 John Wiley & Sons, Inc. 相似文献
996.
体外丹参、藻酸双酯钠对脑血栓形成患者红细胞与内皮细胞粘附的影响 总被引:3,自引:0,他引:3
丹参、藻酸双酯钠是临床治疗脑血管病的常用药。本研究发现,在体外流场中用丹参、藻酸双酯钠分别处理脑血栓形成病人的红细胞后,此红细胞与培养的人脉静脉内皮细胞的粘附数目明显减少、粘附强度明显减弱;而且,在临床常用剂量下藻酸双酯钠的这种抗粘附作用优于丹参。认为丹参、藻酸双酯钠的这种抗粘附作用可能是临床用以治疗脑血栓形成的一个重要机理。 相似文献
997.
阿霉素磁性明胶微球的研究 总被引:2,自引:0,他引:2
报告了阿霉素磁性明胶微球(Adr-MG-ms)的制备与性质,研究了超细氧化铁粒子的合成和磁性明胶微球(MG-ms)在狗体内的栓塞效果。阿霉素磁性明胶微球由2%阿霉素(Adr)、68%明胶和30%的磁铁粒子组成,微球的平均粒径为22μm。在体外实验中,药物释放速度证明微球有缓释的性质。磁铁粒子的平均粒径约为10nm,磁性明胶微球与 ̄(99m)Tc标记磁性明胶微球通过导管分别输入狗的肝动脉内进行栓塞,照相和血管造影显示在未加外磁场时磁性明胶微球在左右肝叶分布几乎相等,而在1200高斯的外磁场作用下,靶部位肝左叶的微球分布是肝右叶的2.25倍,而甲状腺、脑、心脏的微球很微量,结果表明磁性明胶微球在外磁场作用下是一个很好的治疗肝癌的栓塞剂。 相似文献
998.
作者以1%乙酸冲洗SD大鼠子宫内膜,获得子宫内膜酸溶性提取物。利用琼脂糖弥散法和电泳凝胶琼脂糖弥散法抗菌试验发现,子宫内膜提取物有三条主蛋白带对致病性大肠杆菌ML-35P耐药株有强抗菌活性,这三条抗菌蛋白带命名为RatUP-1,RatUP-2和RatUP-3,分别占子宫内膜提取物总蛋白量的4.5%,5.7%和6.6%。虽然提取物存在溶菌的活性,但其含量甚微,在AU一PAGE图谱上亦未能显现溶菌酶条带。本实验的结果提示子宫内膜合成一类抗菌多肽,可能在子宫抗菌机制中发挥重要作用。 相似文献
999.
继青海、甘肃、新疆、河南等地发现Hb Punjab杂合子后,杂们又在安徽省阜阳地区发现两例HbD纯合子,级一级结构分析,确诊为HbDpunjabβ121(CH4)Clu→Gln。这一发现为探讨该地区回族中异常Hb发生率高的原因,研究各民族的亲缘关系以及Hb变对人类健康与的影响提供了遗传学资料。 相似文献
1000.