静息态fMRI观察经颅电刺激对睡眠剥夺后青年志愿者后扣带回皮质连接紊乱的干预作用

目的 采用静息态功能MRI（rs-fMRI）观察经颅电刺激（tDCS）对睡眠剥夺（SD）后青年志愿者双侧后扣带回皮质（PCC）功能连接紊乱的干预作用。方法 对16名健康志愿者间隔施加2次24 h SD，随后随机给予真/假tDCS，于正常睡眠清醒休息状态（RW）、SD后及真/假tDCS后采集fMRI数据并进行蒙特利尔认知评估（MoCA），选取双侧PCC作为种子点，计算种子点与全脑间功能连接，观察RW、SD后及真/假tDCS组间功能连接变化，比较MoCA差异。结果 SD后受试者平均MoCA分值较RW减低（t=8.047，P<0.05）；真tDCS后平均MoCA分值（27.06±1.53）高于假tDCS后（25.13±1.86，t=-3.081，P=0.008）和SD后（24.75±2.41，t=3.306，P=0.005）。SD后双侧PCC与双侧丘脑功能连接较RW上升，而与右侧楔前叶功能连接下降。真tDCS后双侧PCC与双侧丘脑间功能连接较假tDCS后下降，而左侧PCC与右侧楔前叶间功能连接上升。结论 24 h SD能引起PCC网络连接紊乱；tDCS对SD所致网络功能连接紊乱具有一定干预作用。     

Joubert综合征的MRI及DTI表现(附2例报告并文献复习)

目的探讨Joubert综合征的MRI及扩散张量成像(DTI)表现,提高对该病的认识。资料与方法回顾性分析2例Joubert综合征患儿的临床资料、MRI及DTI表现。结果 Joubert综合征的MRI表现包括小脑"中线裂"、中脑"臼齿征"和第四脑室扩大。DTI显示小脑上脚纤维束孤立单侧走行,在中脑内缺乏左右走向水平交叉。结论 Joubert综合征的常规MRI征象具有特征性,DTI可以直接观察纤维束走行异常,提供解剖学证据。     

高碘致发育期大鼠学习记忆能力及海马神经组织凋亡的影响

目的探讨饮用水高碘对大鼠学习能力及海马神经组织凋亡功能的影响。方法将24只SPF级成年SD孕鼠随机分为4组,分别为对照组(饮用自来水)及500、2 500、5 000μg/L碘酸钾暴露组,采用自由饮水方式进行高碘暴露,连续暴露21 d。随机从各剂量组选择断乳雌、雄仔鼠各10只,延用相同剂量进行暴露直至第4个月末。应用Morris水迷宫实验评价大鼠学习记忆能力,采用RT-PCR法检测大鼠海马组织Bcl-2、Caspase-3和Cyt C mRNA的表达水平,采用Western Blot法检测大鼠海马神经组织Bcl-2、Caspase-3和Cyt C蛋白的表达水平。结果与对照组相比,5 000μg/L碘酸钾暴露组雄性大鼠训练不同时间内的平台潜伏期均延长,而2 500μg/L碘酸钾暴露组雌性大鼠仅训练第2天时的平台潜伏期延长,差异均有统计学意义(P0.05)。与对照组相比,各浓度碘酸钾暴露组大鼠穿越平台的次数均下降,差异有统计学意义(P0.05);而空间探索时间、路径比例均无明显变化。随着碘酸钾暴露浓度的升高,雄性大鼠穿越平台次数呈下降趋势。与对照组相比,2 500μg/L碘酸钾暴露组大鼠海马神经细胞Caspase-3基因表达水平升高,差异有统计学意义(P0.05);而各浓度碘酸钾暴露组大鼠海马神经细胞Bcl-2、Cyt C基因的表达水平均无明显改变。与对照组相比,2 500、5 000μg/L碘酸钾暴露组大鼠海马神经细胞Cyt C和Caspase-3蛋白的表达水平均升高,Bcl-2蛋白的表达水平均降低,差异有统计学意义(P0.05);与500μg/L碘酸钾暴露组相比,5 000μg/L碘酸钾暴露组雄性大鼠海马神经细胞Cyt C和Caspase-3蛋白的表达水平升高,差异均有统计学意义(P0.05)。结论高碘暴露可造成4月龄大鼠空间学习和记忆能力的下降,可能与海马神经细胞发生凋亡有关。     

膳食营养对小学生氟斑牙发病程度的影响

Objective To investigate the effect of dietary nutrition on dental fluorosis degrees of school children in endemic fluorosis areas. Methods Two hundred and eight children aged 8 to 12 years were chosen using cluster random sampling method from a village of municipal suburban and a town of autonomous region, both with a history of serious endemic fluorosis. Morning urinary fluoride was measured by fluoride ion electrode. The Tooth Surface Index of Dean was applied to measure the severity of dental fluorosis. Food and nutrient intakes were analyzed according to the 3-day diet records and duplicate meals. Results The urinary fluoride concentration of the children in the town [(6.80±3.90)mg/L]was much higher than those in the village [(5.20±2.75)mg/L, t= 3.21, P < 0.01]. Dental fluorosis index of the children in the town was 1.9, higher than that of the village of 1.8 (H=10.266, P < 0.01). The town had more children with fluoride tooth degree higher than Ⅱ [63.3%(57/90)]than the village did[48.3% (57/118), χ2=4.633, P < 0.05]. A 3-days diet records showed that children in the village ate more protein, calcium, vitamin C and so on but less dietary fiber, vitamin E, magnesium than those in the town did(all P < 0.01). Duplicate meals revealed that children in the town had more daily intake of magnesium, lithium, lead and less cadmium than those of the village did(P < 0.01 or < 0.05). Children in the village had higher intake of fluoride[(2.24±1.18)mg/d]than those of the town [(1.78±0.06)mg/d, t = 4.21, P < 0.01]. Conclusions Healthy diet can reduce the incidence of dental fluorosis or mitigate the degree of the impairment. This study can provide scientific basis for the future control and elimination of endemic fluorosis.     

高碘暴露儿童智商与单胺类神经递质的关系研究

目的探讨高碘对儿童智力和单胺类神经递质的影响以及单胺类神经递质与智商高低的关系。方法根据水中碘化物质量浓度从天津市滨海新区和静海区中选取适碘地区(10μg/L≤水中碘化物质量浓度150μg/L)、高碘一区(150μg/L≤水中碘化物质量浓度300μg/L)和高碘二区(水中碘化物质量浓度≥300μg/L),按照整群随机抽样的方法从中抽取399名(7～12)岁儿童,采用《中国联合型瑞文测验》(中国农村版)测定儿童智商,采用ELISA测定血浆单胺类神经递质多巴胺(DA)、5-羟色胺(5-HT)、去甲肾上腺素(NE)和肾上腺素(E)的含量。结果高碘二区儿童的IQ值为109. 59±14. 24,低于适碘地区和高碘一区儿童,差异有统计学意义(均P0. 05)。高碘二区儿童的DA质量浓度为(321. 69±104. 95) ng/m L,高于适碘地区和高碘一区,5-HT质量浓度为(142. 62±71. 64) ng/m L,比另外两个地区质量浓度低,差异均有统计学意义(均P0. 05)。而NE和E的含量在3组地区无统计学差异(均P0. 05)。阈值分析显示碘暴露与DA呈明显的非线性关系,当儿童尿碘水平在492. 75μg/L以下,血浆DA质量浓度随尿碘水平的升高而明显升高。DA与IQ也呈明显的非线性关系,当儿童DA质量浓度小于80. 0 ng/m L,体内DA每升高1 ng/m L,智商升高0. 1分;当DA质量浓度在(80. 0～359. 8) ng/m L范围内,DA每升高1 ng/m L,智商降低0. 1分。而尿碘对5-HT、NE和E的影响以及5-HT、NE和E与智力的关系均未见显著的线性关系或阈值效应。结论碘暴露过多儿童的DA代谢紊乱可能与其智商降低有关,且DA与智商存在阈值效应。     

转HJC-1和G6-EPSPS基因抗虫耐草甘膦水稻表达蛋白在模拟胃肠环境中的稳定性研究

目的 研究HJC-1和G6-EPSPS基因表达的蛋白分别在模拟胃液和模拟肠液中的消化稳定性.方法 采用美国1995年药典提供的模拟胃液和模拟肠液配方,在体外建立模拟胃肠环境消化体系,测定HJC-1和G6-EPSPS基因表达的蛋白质在胃肠环境中的稳定性.蛋白质在模拟胃、肠液中的浓度分别为5.0和2.0 mg/ml.在蛋白质与模拟胃、肠液反应后的0、15、30 s,1、2、5、10、20、30和60 min准确取样,根据SDS-PAGE凝胶电泳结果,判断蛋白质在模拟胃、肠液环境中的稳定性.结果 HJC-1基因表达的蛋白质在模拟胃液和模拟肠液中均在15s内全部降解；G6-EPSPS基因表达的蛋白质在模拟胃液中30 s内全部降解,在模拟肠液中60 min内不能完全降解.结论 HJC-1基因表达的蛋白质在模拟人体胃肠环境中不稳定,易被降解.G6-EPSPS基因表达的蛋白质在模拟人体胃环境中不稳定,易被降解；在模拟人体肠环境中稳定,不易被降解.     

复合对氯间二甲苯酚消毒剂消毒效果研究

目的观察复合对氯间二甲苯酚消毒剂对细菌繁殖体的杀灭效果,为其消毒应用提供科学依据。方法采用悬液定量杀菌试验方法进行消毒相关性能观察。结果用含900 mg/L对氯间二甲苯酚的消毒剂作用1.5 min,对悬液内金黄色葡萄球菌、大肠埃希菌和铜绿假单胞菌平均杀灭率对数值〉5.00;作用3 min,对悬液内白色念珠菌平均杀灭率对数值〉4.00;用含对氯间二甲苯酚2 200 mg/L的消毒液擦拭消毒3 min,对手臂上自然菌的平均杀灭对数值为1.76,对木质油漆表面上的自然菌平均杀灭对数值为1.71,浸泡消毒3 min,对棉质白平纹布上自然菌的平均杀灭对数值为1.28;浸泡4种金属片72 h,对不锈钢、铝为基本无腐蚀,对铜、碳钢为轻度腐蚀。结论对氯间二甲苯酚与乙醇复配的消毒剂具有良好的杀菌效果,可用于物体表面及衣物等的消毒。     

膳食营养对小学生氟斑牙发病程度的影响

Objective To investigate the effect of dietary nutrition on dental fluorosis degrees of school children in endemic fluorosis areas. Methods Two hundred and eight children aged 8 to 12 years were chosen using cluster random sampling method from a village of municipal suburban and a town of autonomous region, both with a history of serious endemic fluorosis. Morning urinary fluoride was measured by fluoride ion electrode. The Tooth Surface Index of Dean was applied to measure the severity of dental fluorosis. Food and nutrient intakes were analyzed according to the 3-day diet records and duplicate meals. Results The urinary fluoride concentration of the children in the town [(6.80±3.90)mg/L]was much higher than those in the village [(5.20±2.75)mg/L, t= 3.21, P < 0.01]. Dental fluorosis index of the children in the town was 1.9, higher than that of the village of 1.8 (H=10.266, P < 0.01). The town had more children with fluoride tooth degree higher than Ⅱ [63.3%(57/90)]than the village did[48.3% (57/118), χ2=4.633, P < 0.05]. A 3-days diet records showed that children in the village ate more protein, calcium, vitamin C and so on but less dietary fiber, vitamin E, magnesium than those in the town did(all P < 0.01). Duplicate meals revealed that children in the town had more daily intake of magnesium, lithium, lead and less cadmium than those of the village did(P < 0.01 or < 0.05). Children in the village had higher intake of fluoride[(2.24±1.18)mg/d]than those of the town [(1.78±0.06)mg/d, t = 4.21, P < 0.01]. Conclusions Healthy diet can reduce the incidence of dental fluorosis or mitigate the degree of the impairment. This study can provide scientific basis for the future control and elimination of endemic fluorosis.     

膳食营养对小学生氟斑牙发病程度的影响

Objective To investigate the effect of dietary nutrition on dental fluorosis degrees of school children in endemic fluorosis areas. Methods Two hundred and eight children aged 8 to 12 years were chosen using cluster random sampling method from a village of municipal suburban and a town of autonomous region, both with a history of serious endemic fluorosis. Morning urinary fluoride was measured by fluoride ion electrode. The Tooth Surface Index of Dean was applied to measure the severity of dental fluorosis. Food and nutrient intakes were analyzed according to the 3-day diet records and duplicate meals. Results The urinary fluoride concentration of the children in the town [(6.80±3.90)mg/L]was much higher than those in the village [(5.20±2.75)mg/L, t= 3.21, P < 0.01]. Dental fluorosis index of the children in the town was 1.9, higher than that of the village of 1.8 (H=10.266, P < 0.01). The town had more children with fluoride tooth degree higher than Ⅱ [63.3%(57/90)]than the village did[48.3% (57/118), χ2=4.633, P < 0.05]. A 3-days diet records showed that children in the village ate more protein, calcium, vitamin C and so on but less dietary fiber, vitamin E, magnesium than those in the town did(all P < 0.01). Duplicate meals revealed that children in the town had more daily intake of magnesium, lithium, lead and less cadmium than those of the village did(P < 0.01 or < 0.05). Children in the village had higher intake of fluoride[(2.24±1.18)mg/d]than those of the town [(1.78±0.06)mg/d, t = 4.21, P < 0.01]. Conclusions Healthy diet can reduce the incidence of dental fluorosis or mitigate the degree of the impairment. This study can provide scientific basis for the future control and elimination of endemic fluorosis.