三氯乙烯对角质形成细胞线粒体功能和形态的影响

目的探讨三氯乙烯（TCE）对皮肤细胞的毒性机制。方法以不同浓度（0．125、0．500和2．000mmol／L）TCE处理体外分离培养的正常人角质形成细胞（KC），同时设培养基对照组和体积分数为1％的丙酮对照组，然后：（1）分别进行四甲基偶氮噻唑蓝（MTT）试验和ATP酶活力测定来检测细胞毒性和线粒体的代谢变化；（2）采用罗丹明123染色方法，借助流式细胞仪检测线粒体膜电位变化情况；（3）通过透射电子显微镜观察线粒体形态学的改变。结果TCE染毒后，细胞活力随着时间延长和剂量的增加而减小，线粒体酶活力抑制率增加，ATP酶活力减小；线粒体膜电位水平从染毒开始到8h迅速下降2．000mmol／LTCE染毒8h后Rh123荧光强度（8．20±0．66）与对照组（18．73±0．45）相比，差异有统计学意义（P〈0．01）；8h以后则变化不大，12和24h Rh123荧光强度与8h组比较，差异无统计学意义（P〉0．05），线粒体膜电位随染毒剂量的增加呈明显的剂量-效应关系。电镜下可见，TCE处理组线粒体出现肿胀，空泡变性，基质减少，部分嵴消失，对照组线粒体结构完整，基质分布均匀，可见线粒体嵴。结论TCE可以导致KC线粒体功能和形态发生明显改变，这些变化在TCE诱导的KC毒性中具有重要的意义。     

银杏叶提取物对三氯乙烯诱导的人角质形成细胞凋亡的影响

目的研究体外培养条件下银杏叶提取物(ginkgo biloba leaf extracts,EGb)对三氯乙烯(trichloroethylene,TCE)诱导的正常人表皮角质形成细胞(normal human epidernis keratinocyte,NHEK)凋亡的影响。方法体外培养条件下,用中性红吸附试验(NRU)测定TCE对NHEK的中性红吸附减少50%的质量浓度(NR50值)和EGb的最低有效保护质量浓度。用透射电子显微镜(transmission electron microscope,TEM)观察细胞凋亡形态学改变,流式细胞仪(flow cytometer,FCM)测定细胞DNA含量并计算凋亡发生率。结果TCE对NHEK的NR50值为4.53(3.92~5.13)mmol/L;用10、50、100、150和200 mg/L EGb预孵育NHEK 2 h时,由2.0 mmol/L TCE引起的细胞活力的下降随EGb剂量的增加逐渐恢复,且150 mg/L为最低有效保护剂量。TCE可引起NHEK的超微结构呈凋亡改变,凋亡发生率呈剂量依赖式增加。与0.125、0.5和2.0 mmol/LTCE暴露组相比,150 mg/L EGb预孵育组,细胞超微结构恢复到正常对照组水平,凋亡发生率明显减少。结论体外培养条件下,EGb可以抑制TCE诱导的NHEK的细胞凋亡。     

HIGH-IODIDE ENDEMIC GOTTER

Epidemiologic survey reveals that endemic goiter is prevalent among the inhabitants of 6 villages (Group A) situated near the sea coast in Huanghua Count.y, Hebei Province. Thes.e viI- lagers all drink deep-well water with high iodine content. Average goiter incidence is 7.3%, and physio- logicalfy enlarged thyroid glands 28.36%. Only 5.99% of the patients have goiter larger than Grade I, none have Grade m. Only 5.36%。 of the goiter is nodular type. No endemic cre- tinism is found. Urine iodine is very high; thyroid 24 hr 131I uptake js very low; serum T4,T3 and TSH are all within normal range. Two other villages (Group B) in the vicinity are similarly examined, the inhabitants are also fishers, but they drink old fashioned shallow well water, the iodine content of which is normal. The urine iodine excretion is lower than that of Group A but is still distinctly higher than in Tianjin residents. They have a l.52% goiter in- cidence and 8.73% incidence of physiologically enlarged thyroid.     

碘与人群中甲状腺肿流行关系的探讨

多年来,人们认为碘缺乏是地方性甲状腺肿的基本原因,摄入的碘越少,甲状腺肿的流行率越高。尽管Muarray等报告了,服用药理剂量的碘可引起甲状腺肿;Suzuki也报导了日本北海道渔民,食用海藻引起了碘致的地方性甲状腺肿。但1974年,泛美卫生组织仍以尿碘越少,甲状腺肿越严重,作为评定地方性甲状腺肿病区严重度的标准;1976年,Mitchell等也认为“普通甲状腺肿,实际上是一种碘缺乏的疾病”。因此,迄今国内外绝大多数的地方性甲状腺肿研究工作,几乎都在低碘地区进行。但甲状腺肿在高碘地区和中碘地区的流行率又是怎样?从低碘、中碘到高碘地区甲状腺肿的发病趋势如何?尚缺少明确     

不同组织T_3的来源、调节及病理生理研究进展

人体内甲状腺素(T_4)都是甲状腺产生和分泌的,80%的三碘甲腺原氨酸(T_3)是在甲状腺以外的组织中由T_4脱碘而来。T_3对代谢的作用比T_4大3～4倍。T_3是甲状腺激素在细胞水平的主要活性形式,T_4被认为是激素原(Prehopmone)。近年来对机体内T_4向T_3的转换进行了大量研究工作,发现某些“甲状腺功能正     

山西省市售保健食品标识现状调查与对策

保健食品的标签、产品说明书是消费者了解产品功能作用、指导合理选购和科学食用保健食品重要媒介之一 ,如果传达错误信息 ,将导致消费者误用或滥用保健食品。因此 ,对保健食品的标签说明书标识加强卫生监督和管理十分重要。为了解山西省市售保健食品标识标注情况 ,给今后保健食品监督工作的进一步开展提供参考 ,结合卫生部开展健康相关产品监督抽检工作 ,我们于 1999年 10月 -2 0 0 0年 3月先后 4次对山西省市售保健食品标签、产品说明书以及部分产品宣传材料进行了专项调查。1　材料与方法1 1　调查对象与方法　按照卫生部市场保健食品标…     

脑发育临界期的实验研究

昆明种小鼠随机分为四组(A、B、C、D),B、C、D三组在孕15天～生后30天内饲以0.2％甲硫嘧啶,同时C和D组分别于生后16～30天和1～15天注射甲状腺素。B组仔鼠在36天龄时呈克汀病样改变:体重及运动量降低,学习能力下降,脑湿重、全脑DNA和核密度低于对照组A。C组基本上同于B组,但DNA和核密度高于B组,低于A组。D组尽管体重和运动量降低,但脑重和学习能力接近于对照组A,明显高于C组。因此生后1～30天内的甲状腺素缺乏可以导致脑发育落后,在整个脑发育临界期内,生后1～15天对小鼠中枢神经系统的发育最为重要。     

烧伤病房肠杆菌科细菌耐药性及其危险因素分析

Objective To study the risk factors of infection of extended-spectrum beta-lactamases (ESBL) -producing strains and drug resistance of Enterobacteriaceae that infected burn patients. Methods A retrospective study was performed on clinical information of 92 patients with Enterobacteriaceae infection in our burn unit from January 2001 to December 2008. The distribution and drug resistance of Enterobacteriaceae , and the detection rate, drug resistance of ESBL-producing strains, and its risk factors of nosocomial infection were analyzed. Data were processed with Chi-square test. Results One hundred and nine strains of Enterobacteriaceae were isolated, with 38 (34.9%) strains of Enterobacter cloacae , 25 (22.9%) strains of Escherichia coli , 22 (20. 2%) strains of Klebsiella pneumoniae , 13 (11.9%) strains of Proteus mirabilis , and 11 (10. 1%) other strains of Enterobacteriaceae . Enterobacteriaceae were moderately or highly resistant to antibiotics except imipenem, resistance rate of which was less than 8. 0%. ESBL-producing strains accounted for 44. 0% in Escherichia coli , and 77. 3% in Klebsiella pneumoniae . Drug-resistance rate of ESBL-producing strains to antibiotics was obviously higher than that of non ESBL-producing strains. Length of hospital stay longer than 20 days, and use of the third-generation cephalosporin longer than 5 days, quinolone antibiotics longer than 7 days, and topical antibiotics longer than 5 days were the risk factors of nosocomial infection caused by ESBL-producing strains, comparing with non ESBL-producing strains, the difference was statistically significant (with χ2 value respectively 5.491 , 4.441, 15. 186, 4. 938 , P values all below 0. 05) . Conclusions Enterobacteriaceae strains in burn unit of our hospital are highly drug resistant, with high lactamase-producing rates, calling for intense monitor to control the risk factors that predispose the infection of ESBL-producing strains in order to lower the infection rate.     

肝毒净治疗胆瘀型肝炎60例疗效观察

瘀胆型肝炎自觉症状较轻,但常有明显肝肿大,皮肤瘙痒,肝功能检查显示胆红素高,以直接胆红素为主,谷丙转氨酶中度增高或增高不明显,2006年以来我们用肝毒净治疗瘀胆型肝炎并与地塞米松静脉滴注治疗30例对比,疗效满意.