单细胞凝胶电泳测定国产甲基叔丁基醚致DNA损伤

随着甲基叔丁基醚（ＭＴＢＥ）的广泛使用，其致突变效应及遗传毒性已引起关注。本实验采用单细胞凝胶电泳（ＳｉｎｇｌｅＣｅｌｇｅｔＡｓａｙ；ＳＣＧ）技术测试国产ＭＴＢＥ对人的外周血有核细胞的ＤＮＡ损伤作用。方法（１）样品ＭＴＢＥ１：国产，纯度９７％；ＭＴＢ...     

异佛尔酮二异氰酸酯毒理学研究

经ＧＰＭＴ法检测，２５％异佛尔酮二异氰酸酯（ＩＰＤＩ）对豚鼠的致敏率为５０％，属中等致敏物。ＩＰＤＩ对小鼠脾脏抗体生成细胞有抑制作用，但可刺激豚鼠Ｔ淋巴细胞及淋巴细胞转化功能。Ａｍｅｓ试验阴性，１６６ｍｇ／ｋｇＩＰＤＩ可诱导大鼠骨髓染色体畸变、小鼠骨髓嗜多染红细胞微核率增高、小鼠骨髓细胞ＳＣＥ增加及ＵＤＳ试验阳性。ＩＰＤＩ５３～４２４ｍｇ／Ｌ对小鼠骨髓细胞ＤＮＡ合成有明显抑制作用，表明ＩＰＤＩ对体细胞具有断裂剂活性和损伤ＤＮＡ作用。小鼠精子畸形试验和睾丸染色体畸变试验表明对生殖细胞无明显损伤作用。大鼠致畸试验说明ＩＰＤＩ为不致畸物。职业接触ＩＰＤＩ人群调查表明，接触者有明显的粘膜和呼吸道刺激症状，高浓度接触者肺功能（ＦＶＣ、ＦＥＶ１．０）较对照组有下降趋势，其他心、肝、肾功能、外周血淋巴细胞亚群检查、染色体畸变分析、内科、神经系统检查均与对照组无显著性差异。     

甲基叔丁醚及其代谢产物对HL—60细胞的遗传毒性测定

应用单细胞凝胶电泳法（ＳＣＧＥ）测定新型汽油添加剂甲基叔丁醚（ＭＴＢＥ）及其代谢产物叔丁醇（ＴＢＡ）、α－羟基异丁酸（ＨＩＢＡ）和甲醛引起的人白血病细胞（ＨＬ－６０细胞）ＤＮＡ损伤，以乳酸脱氢酶的释放评价其细胞毒性。结果显示，ＭＴＢＥ、ＴＢＡ和ＨＩＢＡ在１～３０ｍｍｏｌ／Ｌ浓度范围内能够引起ＤＮＡ损伤并有明显的剂量反应关系；另一代谢产物甲醛在浓度５μｍｏｌ／Ｌ时即可产生ＤＮＡ损伤，但浓度升高时出现ＤＮＡ迁移减少。提示ＭＴＢＥ及其代谢产物可能具有遗传毒性。然而在引起ＤＮＡ损伤的剂量范围内却没有观察到ＭＴＢＥ、ＴＢＡ和ＨＩＢＡ的细胞毒性，而甲醛则表现明显的细胞毒性作用     

应用单细胞凝胶电泳技术检测辐射致外周血淋巴细胞DNA损伤

应用单细胞凝胶电泳试验 （ＳＣＧＥ） 分别检测了受γ射线照射后小鼠及从事Ｘ 射线探伤工人的外周血淋巴细胞ＤＮＡ 单链断裂（ｓｓｂ） , 结果发现： ０－５Ｇｙ 和５－０Ｇｙ 的γ射线照射组小鼠, 外周血淋巴细胞彗星百分率显著高于对照组; 从事Ｘ 射线探伤工人的外周血淋巴细胞彗星百分率也显著升高。提示ＳＣＧＥ 检测的ＤＮＡｓｓｂ 可作为射线对健康影响的早期生物学指标。     

猕猴桃汁抗环磷酰胺致突变作用的机理

目的用大鼠外周血双核淋巴细胞微核测试法（ＣＢＭＮＴ），在哺乳动物整体水平，研究猕猴桃汁抗环磷酰胺（ＣＰ）的致突变作用以及生物转化Ⅱ相酶的作用。方法测定大鼠外周血双核淋巴细胞微核细胞率及肝组织中总谷胱甘肽硫转移酶（ＧＳＴ）、尿苷二磷酸葡萄糖醛酸转移酶（ＵＤＰＧＴ）、谷氨酰胺转肽酶（γＧＴ）活性。结果猕猴桃汁对ＣＰ诱发的大鼠外周血双核淋巴细胞微核细胞率有显著抑制作用，能明显诱导大鼠肝脏总ＧＳＴ、ＵＤＧＴＰ活性，但对γＧＴ活性无显著影响。大鼠外周血双核淋巴细胞微核细胞率与总ＧＳＴ、ＵＤＧＴＰ活性呈明显负相关。结论猕猴桃汁抗ＣＰ致微核形成作用的机理可能是通过诱导机体外来化合物代谢解毒酶系，加速ＣＰ的代谢灭活     

某厂放射作业人员外周血淋巴细胞DNA损伤的研究

目的 应用单细胞微量凝胶电泳法（ＳＣＧＥ）,俗称慧星试验,探讨小剂量Ｘ射线接触者外周血淋巴细胞ＤＮＡ损伤的情况。方法 选择３２例射线作业保同为接触组和３３例非接触人员为对照组,通过ＳＣＧＥ法测定他们淋巴细胞ＤＮＡ的损伤。结果 射线组工人淋巴细胞ＤＮＡ损伤率明显高于对照组（Ｐ〈０．０１）,ＤＮＡ链的断裂损伤程度和作业人员的工作时间有显著相关。结论 射线工作者长期受职业性小剂量照射可引起外周血淋巴细胞     

微囊藻毒素LR对小鼠肝脏和淋巴细胞的损伤效应

[目的]研究不同剂量微囊藻毒素LR（MCLR）经灌胃途径对小鼠肝细胞及外周血淋巴细胞细胞的损伤效应。[方法]生化法测定血清中谷丙转氨酶（ALT），谷草转氨酶（AST），碱性磷酸酶（AKP），γ-谷氨酸转移酶（γ-GT）和乳酸脱氢酶（LDH）含量，单细胞凝胶电泳试验（彗星试验）测定外周血淋巴细胞DNA迁移长度。[结果]MCLR在1μg/L浓度下即可引起ALT，LDH的显著升高；在达到100μg/L浓度时可引起ＡＫＰ明显升高；但各剂量组ＡＳＴ，γ－ＧＴ与对照组相比无显著差异；不同剂量ＭＣＬＲ均可引起外周血淋巴细胞ＤＮＡ迁移长度增加，且有剂量－反应关系。［结论］ＭＣＬＲ在１μｇ／Ｌ低浓度下对小鼠肝细胞及外周血淋巴细胞可产生一定损伤作用。     

酸角对Brdu和MNNG致突变作用的影响

用人外周血淋巴细胞进行姐妹染色单体互换（ＳＣＥ）和微核（ＭＮ）试验，研究酸角抗Ｂｒｄｕ和ＭＮＮＧ的诱变作用。结果酸角能降低Ｂｒｄｕ诱发的ＳＣＥ，试验组的ＳＣＥ频率随酸角剂量增加而降低，与对照组比有统计学意义（Ｐ〈０．０５）；酸角能明显降低ＭＮＮＧ诱发的ＳＣＥ和ＭＮ，试验组的ＳＣＥ频率和ＭＮ发生率与阳性对照组比较差异非常显著（Ｐ〈０．０１），并有明确的剂量－反应关系，ＳＣＥ抑制率为６２．３８￣９４．     

吸烟与温石棉单独及联合作用对人胚肺细胞DNA链断裂的影响

目的研究吸烟与温石棉对细胞的遗传毒性。方法采用单细胞凝胶电泳技术（ＳＣＧＥ），在体外实验中测定了香烟烟雾溶液（ＣＳＳ）与温石棉（ＣＨ）单独及联合作用于人胚肺（ＨＥＬ）细胞时ＤＮＡ链断裂的情况。结果ＣＳＳ与ＣＨ单独与ＨＥＬ细胞作用１小时，均可使ＤＮＡ链断裂明显增多，当二者以３种不同的剂量组合联合作用时，均可协同增加ＤＮＡ链断裂。结论ＣＳＳ和ＣＨ单独作用均为肿瘤启动剂；当二者联合作用时可协同启动肿瘤的发生。     

汞化合物对人体外淋巴细胞的DNA损伤的比较研究

对人体外淋巴细胞用不同浓度的甲基氯化汞（ＭＭＣ）和氯化汞（ＭＣ）处理１ｈ，观察ＤＮＡ损伤的程度，采用细胞琼脂糖凝胶电泳技术（ＳＣＧＥ）进行比较研究。这两种汞化物均不同程度的显示了剂量反应关系。ＤＮＡ损伤的程度从１０－５ｍｏｌ／Ｌ起与空白对照相比，呈现有意义的增加，细胞ＤＮＡ断裂频率的增加与毒性呈现为线性增长的关系。剂量愈高，则ＤＮＡ的彗尾链愈长，两种化合物在同样的实验条件下显示了相似的分裂剂的潜能，氯化汞表现出的遗传毒性更明显     

Trends in meningococcal disease in Italy in 1988

Meningococcal disease in Italy decreased 15% in 1988 from the previous year (290 vs. 342 cases). The decline was particularly evident in military cases (1.7/100,000 in 1988 vs. 5/100,000 in 1987) reflecting the full coverage of bivalent serogroup (A + C) meningococcal polysaccaride vaccine in army recruits, achieved since January 1988. The highest proportion of cases was seen in people older than 25 years of age (25%). Serogroup C constituted 60% of the isolates, while 19% belonged to serogroup B. The proportion of strains resistant to sulphonamides was 45%, while 15% were resistant to Minocycline and none to Rifampin. Out of the five military cases, only one (due to serogroup C) was attributable to the vaccine failure. A single coprimary case, but no secondary cases occurred among civilians. These findings are consistent with the trends reported in Italy in the previous years.     

Benzene in blood and phenol in urine in monitoring benzene exposure in industry

Determinations of benzene concentration in blood and of phenol in urine were made by head-space gas chromatography techniques on samples taken near the end of the work day from two groups of workers potentially exposed to low levels of benzene in the work-place atmosphere. Preliminary results suggest that benzene in blood is more reliable than phenol tests for assessing both exposure and uptake of benzene. Normal values of phenol in urine (10 mg/liter or less) were found in nearly all those cases in which benzene was detected in the blood.     

Changes in immune function in asthma in the elderly

Asthma is an inflammatory disorder of the airway. The airway inflammation of asthma is typically an allergic inflammation characterized by cells and mediators described as a "Th2" inflammatory response. There is a growing body of evidence describing changes in the function of immune cells upon aging, a phenomenon referred to as "immunosenescence". Several studies utilizing animal models and human subjects with asthma have begun to explore age-related effects on the airway inflammation in asthma. This review explores the existing data on the presence and effects of immunosenescence or age-related changes in immune function in asthma.     

Changes in Fatty Acid Composition in Beef in Italy

Results from a study conducted in Italy concerning the updating of composition data of beef consumed in Italy are reported here. The study required a very wide sampling plan with regard to both animals and cuts to analyse. Data related to lipid composition of the most widely used type of beef consumed in Italy (young bull, 16–22 months old) show a reduction in total lipid content (which, according to the cuts, ranges between 1.8 and 10.2%) and a substantial change in fatty acid composition, with a high % of polyunsaturated fatty acids (mean 20% of total fatty acids). Such data have been confirmed by other studies conducted in Italy, and are in contrast with data reported in the tables of food composition from other countries, reporting a fatty acid composition characterized by a high fatty acid saturation degree. The occurrence of long-chain polyunsaturated fatty acid is probably due to the high ratio of phospholipids: triglycerides, occurring when the content in intramuscular lipid is very low; to the young age of animals; to the reduced activity of the rumen, where saturation of fatty acids occurs. It may be concluded that a fatty acid composition, which is particularly rich in polyunsaturated fatty acids, seems typical for Italian products.     

2015年郑州市饮用水放射性水平状况调查

目的了解郑州市不同地区、不同季节、不同水源类型的放射性水平。方法分别于丰水期和枯水期采集郑州市区黄河水源水、井水源水、丹江口水源水、出厂水和末梢水各一份;以县为单位,每单位采集出厂水、末梢水、水库水、河水、井水各1份,按《生活饮用水生活标准检验方法》(GB/T 5750.13-2006)检测饮用水中总α和总β放射性水平,依据《生活饮用水卫生标准》(GB 5749-2006)进行判定。结果丰水期、枯水期水体总α、总β放射性水平均低于国家标准限值。结论郑州市不同水源类型均处于正常的天然放射性本底水平。     

Occupational stress in nurses in psychiatric institutions in Taiwan

Nurses are known to be exposed to occupational stress. However, occupational stress is not well documented for nurses in psychiatric institutions in Taiwan. A cross-sectional study was conducted to explore the work-related stress and risk factors of nurses in psychiatric institutions in Taiwan. A structured questionnaire was distributed to nurses at five state-owned psychiatric hospitals in Taiwan in 2001. Demographic information, working environment, and personal health status were inquired. Occupational stress was assessed based on the Chinese version of Job Content Questionnaire (JCQ). General health status and mental health were evaluated by the International Quality of Life Assessment Short Form-36 (IQOLA SF-36). A total of 573 questionnaires were disseminated to nurses and 518 (90.4%) were satisfactorily completed by nurses, including 408 female full-time nurses who had been in their current work for more than 6 months. In the past one month, 17.2% of nurses reported being under significant stress often or always. Assault episodes were reported by 45.1% of nurses in the past 6 months. Among the nurses, 16.9%, 25.2%, 50.0%, and 7.8% belong to the "High strain", "Low strain", "Active", and "Passive" groups, respectively. Perceived occupational stress was associated with young age, widowed/divorced/separated marital status, high psychological demand, low workplace support, and threat of assault at work. Lower general health score was associated with low job control, high psychological demand, and perceived occupational stress. A lower mental health score was associated with low job control, high psychological demand, low workplace support, and perceived occupational stress. We concluded that nurses in psychiatric institutions are under significant stress related to work factors.     

Changes in nursing administration in supporting transplantation in Brazil

This historical and bibliographic study aimed to understand how Nursing was organized to support care in transplantation. The HISA, LILACS, BDENF, PERIENF and DEDALUS databases were consulted, and thirteen references were found, ten of which were scientific articles, two were master's dissertations and one was a doctoral thesis. The span of time chosen for study ranges from the date of the first kidney transplant in Brazil (1965), to the date of publication of the last scientific article found in the databases mentioned above (2003). After reading these articles, the ones that were similar in topic were grouped together, thus creating the thematic axis for the presentation of the results. The results showed that the Nursing profession has played an important and active role in transplants ever since the first procedure in 1965.