某体校游泳池氯化消毒副产物浓度及游泳者尿液中8-羟基脱氧鸟苷水平分析

目的通过检测游泳池氯化消毒副产物的浓度以及游泳者暴露后尿液中8-羟基脱氧鸟苷(8-OHd G)的水平,为进一步研究游泳池氯化消毒副产物暴露人群的健康状况提供参考数据。方法按照《公共场所卫生监测技术规范》(GB/T17220-1998)和《生活饮用水标准检验方法》GB5750-2006)于2013年5-9月对某体校游泳池进行采样检测,酶联免疫吸附法(ELISA)于2013年游泳季开放前(4月)后(10月)分别检测游泳组和对照组尿液中8-OHd G水平。结果该校游泳池三氯甲烷、二氯乙酸、三氯乙酸的浓度水平均值分别为(0.045±0.030)、(0.050±0.018)和(0.031±0.015)mg/L,参照国际泳联标准,其中三氯甲烷浓度超标,游泳组学生在经过一个游泳季后(10月),尿液中8-OHd G平均水平显著高于对照组(t=8.450,P=0.000),且显著高于开放前(4月)(t=8.450,P=0.000);但是游泳组在游泳季开放前(4月)与对照组比较(t=1.391,P=0.170),对照组游泳季开放前(4月)和结束后(10月)比较(t=1.702,P=0.104)尿液中8-OHd G的水平差异均无统计学意义。结论该校游泳池氯化消毒副产物的污染问题不容忽视,长期游泳者尿液中8-OHd G水平较非游泳人群高,可能与长期接触游泳池氯化消毒副产物有关。     

用彗星试验研究饮用水中有机提取物对小鼠睾丸细胞DNA的损伤作用

目的通过彗星试验探讨饮用水两种不同消毒工艺所产生的非挥发性有机提取物对小鼠睾丸细胞DNA的损伤作用。方法设对照组,低、中和高剂量组共4个组,采用彗星试验检测NZ和XC水厂丰水期和枯水期水源水、自来水水样的非挥发性有机提取物对小鼠睾丸细胞DNA的损伤,并进行比较。结果各剂量组都出现了明显的拖尾现象,NZ与XC水厂的拖尾率比较差异无统计学意义。各剂量组的平均尾长明显高于对照组,NZ水厂低剂量组中,枯水期水源水平均尾长(19.3±2.7)μm高于自来水的(16.0±2.5)μm;高剂量组中,丰水期水源水高于自来水。水源水中,枯水期低剂量组低于丰水期、中剂量组高于丰水期;自来水中,枯水期中剂量组低于丰水期,高剂量组高于丰水期。XC水厂低剂量组中,丰水期的水源水平均尾长(15.5±1.0)μm低于自来水的(24.9±2.6)μm,中剂量组中,枯水期水源水高于自来水。水源水中,丰水期低剂量组低于枯水期,中剂量组和高剂量组丰水期高于枯水期;自来水中,丰水期中剂量组高于枯水期。结论 NZ和XC水厂的丰水期和枯水期有机提取物均含有导致小鼠睾丸细胞DNA损伤的物质;水源水与自来水、丰水期与枯水期表现为不同程度的DNA损伤。     

一起草菇中毒的急性毒性研究

目的:探讨草菇中毒的原因并对其毒性进行评价。方法:SPF级NIH小鼠、Hartly白化豚鼠经口灌胃(0.2 ml/10.0 g.bw)、腹腔注射(0.2 ml/10.0 g.bw)染毒,连续观察7 d。结果:草菇生品对NIH小鼠经口灌胃染毒未见明显毒性;对Hartly豚鼠经口灌胃染毒可出现明显中毒症状,并引起动物死亡。草菇生品对NIH小鼠腹腔注射染毒有较强毒性,草菇熟品未见引起中毒反应。结论:草菇生品有一定的毒性,可能引起中毒反应。     

组织学微课教学设计技巧

<正>组织学是一门重要的医学基础课程,主要涉及人体结构细微等特点,枯燥难学~([1])。随着教育改革的不断深化,"微课"~([2])的建设与应用已悄然兴起,作为一种新的教学手段,受到了广大师生们的关注和喜爱。微课设计是微课制作与应用的核心。本文探讨组织学"微课"学设计技巧,旨在与大家分享经验,合力推动相关教学改革。1微课设计的重要性微课设计凝聚着教师的创意,反映教师对课程的理解、教学的认识和对学生的把握,融入设计者的经验和教学积累。微课     

解剖学微课选题的探讨

正微课~([1])是一种短小精悍的在线教学视频。选题是微课制作的第一步,精准选题可以让微课的教学设计、视频制作事半功倍。医学中1/3以上的名词来源于解剖学~([2]),从中选题犹如沙里淘金。现探讨解剖学微课选题技巧,旨在与大家分享经验,合力推动相关教学改革。1解剖学微课选题中存在的主要问题选题不当是当前的主要问题,主要表现在选题过大和选题价值不高。     

二安替比林间甲基苯基甲烷测定食品中的微量钒

钒是人体健康必须的微量营养元素，影响人体健康，因而痕量钒的测定具有重要意义。我们曾研究过二安替比林苯基甲烷类试剂与钒（Ｖ）［１～３］的显色反应，该类反应灵敏度高。在此基础上，我们又合成了新试剂二安替比林间甲基苯基甲烷（ＤＡｍＭＭ），用于钒（Ｖ）的测定...     

二吲哚甲烷诱导荷鼻咽癌裸鼠肿瘤转归及对MDA、SOD和GSH-Px的影响

[目的]探讨3,3-二吲哚基甲烷(3,3-diindolylmethane,DIM)对荷鼻咽癌裸鼠肿瘤体积、丙二醛(Malondiadehycle,MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)活力及凋亡相关蛋白-半胱天冬酶-3信号分子的影响.[方法]采用完全随机的方式将48只BALB/C裸小鼠分为DIM低、中、高(0.004 g/kg.b.w、0.02 g/kg.b.w、0.1 g/kg.b.w)剂量组和溶剂对照组(体积分数为0.5%的羧甲基纤维素钠溶液),分别经口灌喂给予实验动物相应剂量的DIM或对照溶液10 d后,于其背部靠腋窝皮下接种人鼻咽癌细胞株CNE1,继续经口灌喂给予实验动物相应剂量的DIM或对照溶液.实验第30天时处死动物,计量肿瘤体积、留取肿瘤组织进行MDA含量、SOD和GSH-Px活力测定、活化型半胱天冬酶-3活性检测.[结果]DIM各剂量可不同程度地抑制肿瘤生长.与对照组比较,高剂量组SOD活力明显升高(P<0.05)、MDA含量明显降低(P<0.05)、GSH-Px活力明显升高(P<0.05).细胞凋亡的关键执行者活化型半胱天冬酶-3(Cleaved Caspase-3)表达随染毒剂量的增加逐渐增强(P<0.05).[结论]3,3-二吲哚基甲烷可抑制肿瘤生长,其机理可能与通过降低MDA含量,提高SOD活力、GSH-Px活力等途径降低氧化应激程度及通过Caspase-3信号分子诱导凋亡的作用相关.     

广州市自然人群病毒性肝炎血清流行病学研究

目的了解广州市自然人群病毒性肝炎的血清流行病学特征。方法采取分层多级整群系统随机抽样方法抽取研究对象,对其作流行病学个案调查,并应用酶联免疫吸附试验（ELISA法）检测病毒性肝炎各感染标志物。结果广州市自然人群HAV、HBV、HCV、HDV、HEV、HGV感染率分别为74．47％、64．10％、0．65％、0．13％、1．69％和0．65％;HAV、HBV和HEV的感染率在老城区、新城区和郊市区中的差异有高度显著性意义（P〈0．01）,而HCV、HDV和HGV的差异无显著性意义（P〉0．05）;HBV感染率在男女之间差异有高度显著性意义（P〈0．01）,HCV感染率在男女之间差异有显著性意义（P〈0．05）,而HAV、HDV、HEV和HGV的感染率则无性别差异（P〉0．05）;HAV、HBV、HCV、HDV、HEV、HGV最低感染年龄分别为2岁、2岁、20岁、31岁、5岁和13岁,最高感染年龄分别为90岁、86岁、46岁、67岁、74岁和71岁;HAV、HBV和HEV感染率均与年龄呈正相关（P〈0,01、P〈0,01和P〈0．05）。结论广州市自然人群各型病毒性肝炎感染具有不同的流行病学特征,其中HAV和HBV的感染率较高,HCV、HDV、HEV和HGV的感染水平则较低。     

吲哚-3-甲醇对荷鼻咽癌裸鼠肿瘤转归及抗氧化体系的影响

Objective To observe the effects of indole-3-carbinol (I3C) on the outcome of the tumor as well as the changes of the anti-oxidative system in null mice grafted with nasopharyngeal carcinoma. Methods 48 BALB/c null mice were divided by means of random number table into control group (0. 5% sodium carboxyl methyl cellulose),low dosage (0.02 g/kg),middle dosage (0. 1 g/kg) and high dosage(0. 5 g/kg) of I3C. The mice were administered with different solutions by gavage for 10 days before CNEI cells were inoculated subcutaneously into the back (near the armpit) of the nude mice,then the solutions were continually administered by gavage. The tumor volume was measured and the tumor inhibitory rate was calculated. The level of malondialdehyde (MDA),the activity of superoxide dismutases (SOD),the activity of glutathione peroxidase (GSHPx) and the expression of cleaved caspase-3 were determined on the 31th day of the study. Results I3C could reduce the tumor volume [the tumor volumes of the control group,the middle dosage group and the high dosage group were(4. 13±0. 53)×10-6m3, (3.14±0.71)×10-6m3, (2. 72±0. 29)×10-6m3], as compared with the control, the shrinkage of tumor volume of the middle dosage group and the high dosage group were significant (the t valued at 0. 990 and 1.510, P< 0.01). The tumor inhibitory rates of 3 groups were 3.8%,20.5% and 34.9%,respectively. The contents of MDA in the tumor tissue tended to decrease [the values of control group,the low dosage group,the middle dosage group and the high dosage group were(31.29±2. 51)×10-6mol/L, (30. 12±2. 37)×10-6 mol/ L, (23. 32±1.93)×10-6 mol/L, (16.45±1.43)×10-6 mol/L](F=98. 752, P < 0. 01), and that of the high and the middle dosage group could obviously be reduced (t=8. 970,14. 840, P < 0.01) as compared with the control. The activity of SOD seemed to be elevated according to the increase of I3C dosage [the values were (387.24±23.16)×103 U/L, (399. 37±34. 45)×103 U/L, (431.63±31.24)×103 U/L, (476.45±44. 67)×103 U/L](F=53.444,P < 0. 01). When compared with the control, the SOD activity of the middle and the high dosage group be obviously increased (t=44. 390,89. 210,P <0.01). I3C could also elevate the GSHPx activity [the GSHPx values of the four groups were (226. 98±18.35)×103 U/L, (234.65±15.59)×103 U/L, (247.72±22. 73)×103 U/L, (300. 37±26. 02)×103 U/L](F=25.916,P < 0. 01). The GSHPx of the high dosage group was enhanced remarkable(t=73. 390, P < 0. 01) as compared with the control. The expression of cleaved caspase-3 (relative molecular weight=19 000 000) seemed to be elevated according to the increase of I3C dosage and the relative expression levels of wbich were 0. 87±0. 01,0. 97±0. 01,1.02±0. 06 and 1.14±0.02 (F=39. 864, P < 0. 01). When compared with the eontrol,the elevation of this kind of cleaved easpase-3 was considered statistical significant (the t values were 0. 100,0. 086 and 0. 303, respectively, P < 0. 05). When 13C dosage increased, the expression of cleaved caspase-3 (relative molecular weight=17 000 000) seemed to increased too [the relative expression levels of which were 0.00±0.00,0.05±0.02,0. 11±0.02,0.20±0.02(F=56.629,P<0.01)],and the increase of this kind of cleaved caspase-3 was esteemed significantly as compared with those of the control (the t valued at 0. 046,0. 103 and 0. 193, respectively, P < 0. 05). Linear correlate analysis showed that the correlation coefficients between the shrinkage of tumor volume and the expression of the two kinds of cleaved caspase-3 protein was-0.732 (t=3. 404, P < 0. 01) and-0. 901 (t=6. 642, P < 0. 01). Conclusion I3C could reduce the growth of tumor, the mechanism underlie it could be related to the decrease of the content of MDA as well as the elevated levels of SOD,GSHPx,and perhaps could be related to the apoptosis transducted by cleaved caspase-3.