铅暴露与阿尔茨海默病

阿尔茨海默病(Alzheimer s Disease,AD)是常见的神经变性疾病之一,其发病机制不十分明确,也无从特效治疗,严重影响中老年人的身心健康,因而成为医学的研究热点。实验研究发现,铅暴露与AD发病有关[1]。铅(Pb)是广泛分布在自然环境中的有毒重金属,吸收过量可引起铅中毒。目前,铅污染的特点是浓度低、范围广,对人群健康的影响是低剂量、长期暴露而引起的慢性损害。低浓度Pb具有神经毒性,可对认知学习和记忆等高级脑功能产生有害影响,而且可能是发生AD的病因之一。现就国内外关于铅暴露与AD关系的研究作一综述。1铅暴露与AD职业性和生活性…     

磁共振成像和氢质子磁共振波谱在锰神经毒性研究中的应用

锰是维持人体正常生长发育以及中枢神经系统(CNS)正常功能的一种必需微量元素,但是长期吸入较高浓度的锰烟和锰尘,可引起锰中毒,晚期出现类似帕金森病等锥体外系神经受损的临床表现.肌张力是否增高是诊断慢性锰中毒的关键,但其判定缺乏客观灵敏的定量方法,且肯定的肌张力增高已非早期表现.     

护士在防范医疗纠纷中的作用

通过分析由护士引发的医疗纠纷常见原因，提出护士在防止医疗纠纷中的对策：(1)适应时代需要，转变观念，学法、遵法、守法；(2)护士要按医院规章制度与医疗护理技术操作常规办事，严防护理差错事故发生；(3)有计划地培训年轻护士，提高业务技术水平；(4)掌握电脑技术，维护患的利益，严把收费关；(5)协调护患关系，平息纠纷诱因；(6)加强护士职业道德教育，培养高素质护理队伍。     

常规MRI和1H-MRS在职业性锰暴露致中枢神经损害中的应用价值

Objective MRI and MR hydrogen proton spectroscopy (1H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure.Methods Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1H-MRS.The blood manganese concentration was also collected for each subject.On cerebral axial T1 WI,the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated.The 1H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated.One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis.Eight workers exposed to manganese were followed up one year, and their PI , NAA/Cr before and after follow-up were compared by t test.Results Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T1 WI, while the T2 WI were normal.No high signal intensity was observed on T1WI in any of the healthy workers or manganese poisoning workers.We found that the average PI in manganese exposed group (1.16 ±0.09) was significantly higher (F =24.79 ,P =0.O00)than those of the poisoning ( 1.05 ± 0.07 ) and control groups ( 1.01 ± 0.05 ).The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0.051 ±0.024), (0.047 ±0.018 ), ( 0.043 ± 0.020 ) μg/ml respectively, which was not significantly different ( F = O.623, P =0.541 ) and did not exceed the upper limit of normal reference value ( < 0.10 μg/ml ).There was a significantly correlation between PI and the time span of manganese exposure ( r = 0.67, P = 0.002 ),however, there was no correlation between PI and blood manganese concentration ( r = 0.20, P = 0.427 ).Furthermore, the NAA/Cr ratio decreased variously in the manganese poisoning group ( 1.22 ± 0.07 ) which was significantly lower( F = 4.120, P = 0.023 ) than those of the poisoning( 1.33 ± 0.13 ) and control groups ( 1.31 ±0.13).No statistical significanees were found in the ratios of Cho/Cr and mI/Cr among these three groups(P>0.05).No obvious changes of the PI and NAA/Cr were found in the 8 manganese exposed workers after 1 year follow-up.Conclusion Manganese exposure could lead to the high intensity signal on T1 WI, therefore the increased PI may be the biomarkers of central nerve system damages caused by the occupational manganese exposure.     

常规MRI和1H-MRS在职业性锰暴露致中枢神经损害中的应用价值

Objective MRI and MR hydrogen proton spectroscopy (1H-MRS) were used to detect the abnormal signal and alteration of metabolites, in order to explore the efficacy of these method in evaluating the damages of central nervous system (CNS) induced by occupational manganese exposure.Methods Eighteen workers exposed to manganese without any manganism symptoms, 12 workers with slightly chronic manganese poisoning, and 19 healthy workers were scanned using routine MRI sequence and 1H-MRS.The blood manganese concentration was also collected for each subject.On cerebral axial T1 WI,the signal intensities of ipsilateral globus pallidus and frontal white matter were measured in the visually brightest area (try to select the signal homogeneous region), and the globus pallidus index (PI) was then calculated.The 1H-MRS data was calculated to get the values of the peak height of N-acetylaspartate (NAA), choline (Cho), inositol (mI) and creatine (Cr) and the ratios of NAA/Cr, Cho/Cr, and mL/Cr were also calculated.One way ANOVA was used to compare the values of PI, NAA/Cr, Cho/Cr, mI/Cr and MnB among the three groups, and the correlations between PI and the time span of manganese exposure or blood manganese concentration were analyzed by Pearson correlation analysis.Eight workers exposed to manganese were followed up one year, and their PI , NAA/Cr before and after follow-up were compared by t test.Results Fourteen of 18 cases exposed to manganese without any manganism symptoms showed symmetrically high intensity signal on T1 WI, while the T2 WI were normal.No high signal intensity was observed on T1WI in any of the healthy workers or manganese poisoning workers.We found that the average PI in manganese exposed group (1.16 ±0.09) was significantly higher (F =24.79 ,P =0.O00)than those of the poisoning ( 1.05 ± 0.07 ) and control groups ( 1.01 ± 0.05 ).The blood manganese concentration in manganese exposed group, the poisoning group and the control group were (0.051 ±0.024), (0.047 ±0.018 ), ( 0.043 ± 0.020 ) μg/ml respectively, which was not significantly different ( F = O.623, P =0.541 ) and did not exceed the upper limit of normal reference value ( < 0.10 μg/ml ).There was a significantly correlation between PI and the time span of manganese exposure ( r = 0.67, P = 0.002 ),however, there was no correlation between PI and blood manganese concentration ( r = 0.20, P = 0.427 ).Furthermore, the NAA/Cr ratio decreased variously in the manganese poisoning group ( 1.22 ± 0.07 ) which was significantly lower( F = 4.120, P = 0.023 ) than those of the poisoning( 1.33 ± 0.13 ) and control groups ( 1.31 ±0.13).No statistical significanees were found in the ratios of Cho/Cr and mI/Cr among these three groups(P>0.05).No obvious changes of the PI and NAA/Cr were found in the 8 manganese exposed workers after 1 year follow-up.Conclusion Manganese exposure could lead to the high intensity signal on T1 WI, therefore the increased PI may be the biomarkers of central nerve system damages caused by the occupational manganese exposure.     

脑锰与铁代谢

锰能通过血脑屏障在脑内蓄积,过量蓄积不仅会导致锰中毒而出现类帕金森症状,还会影响脑内其它金属元素的摄取、转运和分布,尤其是脑铁代谢.脑铁代谢异常可能参与锰中毒的发生发展,两者互相作用.本文就脑锰与铁代谢的关系作一综述.     

埋藏式自动转复除颤器治疗扭转型室速1例的护理

冠心病是猝死的最常见病因 ,而室速和 (/或 )室颤是猝死的最常见和最严重的室性心律失常。埋藏式自动转复除颤器 (ICD)技术于 1 980年应用于临床 ,经历了 4个发展阶段 ,我国从 1 990开始将ICD应用于临床。其主要功能为预防由室速及室颤引起的心性猝死。ICD自应用于临床以来 ,已迅速成为有危及生命的室性心律失常患者首选治疗手段。非开胸的电极系统应用 ,使ICD植入的病残率和死亡率显著降低[1 ] 。使室速和 (/或 )室颤引起心性猝死的死亡率从30 %下降为 1 .8%。现把本院 1例ICD治疗不稳定型心绞痛频繁发作 ,导致尖端扭转型室速和阿 -…     

广西某市学龄前儿童血铅水平及其与微量元素的关系

目的探讨广西某市学龄前儿童血铅(Pb)水平及其与锌(Zn)、铜(Cu)、铁(Fe)、钙(Ca)、镁(Mg)、锰(Mn)含量的关系。方法对624名2~5岁学龄前儿童测定血Pb、Zn、Cu、Fe、Ca、Mg、Mn含量,并对血Pb与Zn、Cu、Fe、Ca、Mg、Mn等含量进行相关性分析。结果以美国国家疾病控制中心(CDC)制定的铅中毒标准(血Pb水平≥100μg/L)为界线,学龄前儿童的铅中毒检出率为22.6%,其中男童及其4岁~组铅中毒检出率明显高于女童及其对应亚组;男童血Pb和Cu含量高于女童(P<0.05,P<0.01)。但是,血Pb水平与6种微量元素含量之间未见明显相关关系。结论多元线性回归分析未见学龄前儿童血Pb与Zn,Fe,Cu,Ca,Mg,Mn含量之间有相关关系。     

锰作业工人苍白球磁共振成像改变的研究

、(20.8±7.4)ng/ml.中毒组与对照组比较,t=20.206,P=0.000;与锰暴露组比较,t′=13.144,P=0.000.中毒组与低、高锰暴露亚组比较,t′值分别为12.964、9.957,P=0.000].8例高锰暴露工人1年后追踪调查仅发现作业环境空气MnO2浓度中位数较1年前相比降低,差异有统计学意义(依次为0.89、0.31 mg/m3,Z=-2.142,P=0.032).结论 锰暴露引起工人脑MR T1WI信号明显增强,PI可能是锰致CNS损伤的中枢暴露生物学标志.