铅对染毒大鼠血清超氧化物歧化酶活性和丙二醛含量的变化

目的研究慢性染铅大鼠血清超氧化物歧化酶(SOD)、丙二醛(MDA)的变化及其与血铅的剂量-效应关系,以探讨铅中毒的作用机制.方法 SOD活性测定采用亚硝酸盐显色法,MDA含量测定采用硫代巴比妥(TBA)法.结果与对照组相比,低剂量染铅组大鼠血清SOD活性在60 d以后明显下降(P<0.05);高剂量染铅组SOD活性30 d以后明显降低(P<0.05),MDA亦明显高于对照组(P<0.05).血清SOD与血铅之间存在负相关(r=-0.479,P<0.01)且呈现负向剂量-效应关系;血清MDA与血铅之间存在正相关关系(r=0.496,P<0.01)且呈现正向剂量-效应关系.结论慢性染铅可导致血清SOD活性降低、MDA含量升高,且呈剂量-效应关系.表明脂质过氧化反应可能是慢性铅中毒一个重要的分子机制.     

染铅对大鼠脾脏NOS、NO、SOD、MDA的影响

目的 探讨染铅对大鼠脾脏一氧化氮合酶（NOS）活力、一氧化氮（NO）含量的影响及其与血铅相互关系。方法 Wistar大鼠经饮水（加0，18．4，184．0mg/L醋酸铅，分别供对照组、低剂量组、高剂量组自由饮用）染毒，测定脾脏NOS活力、NO含量、SOD活力、MDA含量。结果 NOS活力高剂量染铅组7d时显著低于对照组和低剂量组（P＜0．05），90d高于对照组和低剂量组（P＜0．05），低剂量组90d高于对照组（P＜0．05）；NO含量高剂量组和低剂量组60d、90d时均显著低于对照组（P＜0．05）；SOD活力高剂量组14d、30d、60d、90d时均低于对照组（P＜0．05），低剂量组30d、90d时显著低于对照组（P＜0．05）；MDA含量高剂量组14d、60d、90d时均显著高于对照组，60d时显著低于低剂量组，90d时显著高于低剂量组（P＜0．05），低剂量组在各时点与对照组比较，差异无显著性（P＞0．05）。血铅与脾脏NO含量呈倒S型剂量－效应曲线；血铅与脾脏SOD活力呈倒抛物线型剂量－效应曲线；血铅与脾脏MDA含量呈正抛物线型剂量－效应曲线。结论 铅可引起大鼠脾脏NOS活力、NO含量、SOD活力、MDA含量改变，表明铅可引起体内氧应激反应导致脂质过氧化损伤。     

染铅大鼠骨髓NOs和NO的变化

目的 探讨染铅对大鼠骨髓一氧化氮合酶（NOS）活力、一氧化氮（NO）含量的影响及其与血铅相互关系。方法 Wistar大鼠经饮水（加0，18．4，184．0mg/L醋酸铅，分别供对照组、低剂量组、高剂量组自由饮用）染毒，测定骨髓NOS活力、NO含量。结果 NOS活力高剂量染铅组在7d、14d时均较对照组和低剂量组高（P＜0．05），其余时点各组间差异无显著性（P＞0．05），NO含量染铅高剂量组在7d、14d时均较对照组和低剂量组高（P＜0．05），60d各剂量组间差异无显著性（P＞0．05），90d高剂量组显著低于对照组（P＜0．05）。结论 染铅导致大鼠骨髓毒性，引起骨髓NOS活力、NO含量改变，表现为染铅早期骨髓NOS活力、NO含量升高，晚期骨髓NOS活力、NO含量降低；但慢性染铅对骨髓NOS活力、NO含量影响的生理机制有待进一步研究。     

铅暴露对一氧化氮及氧自由基代谢的影响

【目的】了解番禺地区儿童铅暴露情况,探讨高水平铅暴露对儿童血浆中一氧化氮(nitricoxide,NO)、一氧化氮合成酶(nitricoxidesynthase,NOS)、超氧化物歧化酶(superoxidedismutase,SOD)、丙二醛(malondial-dehyde,MDA)的影响,以及NO系统与氧自由基之间的相互关系。【方法】对440例1~3岁入托体检的健康儿童,测定其血铅、血浆NO、NOS、SOD及MDA水平。【结果】儿童血铅水平为(0.561±0.211)μmol/L,≥0.483μmol/L(100μg/L)者占51.14%;高水平铅暴露的儿童血浆NOS活性明显降低(P<0.01),NO亦降低,但差异无显著性(P>0.05);NOS与铅、SOD呈负相关,与NO呈正相关,而SOD与MDA呈负相关;以NOS作为因变量进行多元回归分析,回归方程为Y’=4.228-5.309×血铅-0.083×SOD。【结论】环境铅污染对儿童已构成严重的威胁,应引起社会各界高度重视;高水平铅暴露儿童血浆中NOS活性受到明显抑制,使NO的生成减少,而且NOS活性与SOD活性存在有一定相关性。     

铅暴露对发育期小鼠学习记忆能力影响

目的 探讨不同铅暴露水平对发育期小鼠学习记忆能力的影响及脑一氧化氮(NO)、总一氧化氮合酶(NOS)与小鼠学习记忆能力的关系.方法 采用自由饮水(含醋酸铅)的方式对刚断乳小鼠染毒,染毒剂量为0.3,1和3 g/L,每组30只.开始染铅记为第0 d,分别在第7,14,21 d进行血铅、小鼠Morris水迷宫试验及小鼠脑铅浓度、脑NO含量和脑总NOS活性的测定.结果 与正常对照组比较,染毒组小鼠血铅和脑铅浓度增加(P＜0.05);迷宫实验中,第21 d,正常组及染铅0.3,1,3 g/L组平均潜伏期分别为(33.8±7.8),(73.0±12.1),(85.9±12.7),(101.3±19.7)s,各铅暴露组与对照组之间差异有统计学意义(P＜0.05);正常组,0.3,1,3 g/L组脑NO含量分别为(10.27±4.28),(6.07±1.95),(5.63±2.03)和(3.74±1.89)μmol/(g·prot),各铅暴露组与对照组之间的差异有统计学意义(P＜0.05);正常组,0.3,1,3 g/L组脑总NOS活性分别为(6.22±2.42),(4.36±1.76),(2.84±1.42)和(3.25±1.76)U/(mg·prot),各铅暴露组与对照组之间差异有统计学意义(P＜0.05);第21 d,小鼠脑NO含量和脑总NOS与血铅、脑铅浓度及Morris水迷宫逃避潜伏期均呈负相关(r=-0.540,P=0.000;r=-0.520,P=0.000;r=0.755,P=0.000;r=0.709,P=0.000).结论 铅暴露对发育期小鼠学习记忆能力的影响与铅暴露导致的脑NOS活性降低和NO含量减少密切相关,且影响程度与铅的暴露时间及浓度有关.     

铅对大鼠肾脏一氧化氮合酶、一氧化氮影响的研究

目的：探讨慢性染铅过程中大鼠肾脏一氧化氮合酶（NOS），一氧化氮（NO）的变化。方法：Wistar大鼠经饮水加0．0，18．4，184．0mg/L醋酸铅（PbAc)方法染毒，结果：高剂量组大鼠肾脏NOS活力30d后低于对照组（P＜0．05），低剂量染铅组大鼠肾脏NOS活力60d后低于对照组（P＜0．05），低剂量染铅组肾脏NO含量在各时间点上均有降低趋势，但差异无统计学意义（P＞0．05），高剂量组大鼠肾脏NO含量在60d,90d后低于对照组（P＜0．05），结论：铅可导致肾脏NOS活力降低，NO含量降低，可能是铅对肾脏产生细胞毒作用的机制。     

牛磺酸对铅脂质过氧化损伤的拮抗作用

目的探讨牛磺酸(Tau)对铅致细胞脂质过氧化损伤的拮抗作用.方法 40只Wistar大鼠分为5组,即:空白对照组,染铅组,Tau的100、400、800组:为染铅4周后分别以100、400、800 mg@kg-1@d-1 Tau灌胃4周.第8周末处死动物,测定血铅、血清丙二醛(MDA)、超氧化物歧化酶(SOD)和肝、肾组织MDA、SOD、谷胱甘肽(GSH)、谷胱甘肽过氧化物酶(GSH-Px)等指标水平.结果①Tau 100、Tau 400组大鼠血铅水平明显降低,与染铅组相比,差异有显著性(P＜0.05).②Tau 100、Tau 400组大鼠血清MDA含量降低,SOD活力升高,与染铅组相比,差异有显著性(P＜0.05).③各染铅组大鼠肝、肾组织MDA和GSH含量显著升高,SOD、GSH-Px活力明显降低,而Tau可拮抗铅的上述作用.其中,与染铅组相比,Tau 400、Tau 800组大鼠肝、肾MDA和GSH含量显著降低,SOD和GSH-Px活力明显恢复(P＜0.01或P＜0.05).结论 Tau可拮抗铅致大鼠血、肝、肾脂质过氧化损伤,对染铅大鼠有保护作用.     

儿童铅负荷对血清中SOD、NO、NSE的影响

目的观察不同血铅水平对儿童血清超氧化物歧化酶(SOD)、一氧化氮(NO)和神经元特异性烯醇化酶(NSE)的影响,并探讨其影响机制。方法选择健康儿童50人(男26人,女24人),用无火焰石墨炉原子吸收光谱法测定血铅浓度,根据血铅含量分为正常组、低铅组和高铅组。同时测定血清中SOD活力、NO含量和NSE浓度。结果血铅含量,正常组(血铅<0.483μmol/L)18人,占36%,低铅组(血铅0.483~0.965μmol/L)20人,占40%,高铅组(血铅>0.965μmol/L)12人,占24%。随着血铅浓度的升高,SOD活力呈下降趋势,并有显著负相关(r=-0.53,t=4.35,P<0.01)。低铅组儿童血清NO含量低于正常组,但差异无统计学意义(P>0.05);而高铅组则明显低于正常组(P<0.01)。儿童血清NO含量与血铅浓度呈显著负相关(r=-0.42,t=3.24,P<0.01)。随着血铅浓度的升高,NSE浓度呈上升趋势,两者呈显著正相关(r=0.53,t=4.37,P<0.01)。结论血铅升高时体内SOD活力、NO含量下降,而血清NSE浓度随着升高,这可能是铅诱发机体损伤的作用机制。血清中SOD活力和NO含量下降及NSE浓度的升高可作为临床上判断儿童期早期铅损伤的重要指标。     

染铅对大鼠端脑皮质4种生化指标的影响

为研究染铅对大鼠端脑皮质一氧化氮 (NO)、一氧化氮合酶 (NOS)、超氧化物歧化酶 (SOD)、丙二醛(MDA)的影响 ,进一步探明铅的神经毒作用机理。选择Wistar大鼠采用饮水加 0、18 4、184mg L醋酸铅法染毒。结果显示 :与对照组相比 ,低、高剂量组染铅 7d时NOS活力明显升高 (P <0 0 5 )。低剂量组 90d、高剂量组 30d后NOS活力均显著下降 (P <0 0 5 )。 90d时低剂量组NO含量显著低于对照组 (P <0 0 5 ) ,高剂量组NO含量在 14、6 0、90d均显著低于对照组 (P <0 0 5 )。染铅组皮质SOD活力在 30d后明显低于对照组 (P <0 0 5 ) ,高剂量组 30d时皮质SOD活力也较低剂量组低 (P <0 0 5 )。低剂量组皮质MDA含量在 30d后显著升高与对照组比 (P <0 0 5 ) ,高剂量组皮质MDA含量在 14d后显著升高 (P <0 0 5 ) ,且在 14d、90d时 ,高剂量组显著高于低剂量组 (P <0 0 5 )。提示铅所致神经毒性 ,可能与铅引起端脑皮质NO含量、NOS活力、SOD活力、MDA含量改变有关     

铅对大鼠海马一氧化氮合酶和一氧化氮的影响

目的 探讨慢性染铅过程中，大鼠海马一氧化氮合酶（NOS）、一氧化氮（NO）的变化。方法 Wistar大鼠经饮水加0，18．4，184．0mg/L醋酸铅（PbAc)方法染毒。海马NOS活性测定采用NOS催化L－Arg和氧分子生成NO法，海马NO（NO3^- NO2^-)浓度采用硝酸还原酶法。结果 与对照组相比，高剂量染铅组海马NOS活性在早期（7d）显著升高（P＜0．05），30d后显著低于对照组（P＜0．05）。低剂量组大鼠海马NOS活性第7天开始有增高趋势，但差异无显著性，直到60d后显著低于对照组（P＜0．05）。低剂量染铅组大鼠海马NO含量90d时明显低于对照组（P＜0．05）。高剂量组大鼠海马NO含量在60d后显著低于对照组（P＜0．05）。结论 铅可导致海马NOS活性降低，NO含量降低。NOS活性降低及NO含量减少，可能是铅对海马产生神经毒作用的机制。     

企业职工高尿酸血症与血压、血脂、血糖的相关性研究

目的探讨企业职工高尿酸血症（HUA）与血压、血脂、血糖的相关性,为企业进行健康管理提供依据。方法以中国石油长庆油田公司各下属企业为抽样单位,整群随机抽取2个单位,每个单位中所有的HUA者作为HUA组,共720人;同时在尿酸水平正常者中随机选取620人为正常组。通过Logistic回归分析HUA与年龄、性别、血压、血脂、血糖的关系。结果HUA合并高血压、高血脂、空腹m糖受损任意一项、两项、三项的比例均远高于正常组（OR值分别为：4．036,2．562,4．174）。多因素Logistic回归发现：男性、收缩压、总胆固醇、三酰甘油、低密度脂蛋白胆固醇是HUA的危险因素（OR值分别为7．736,2．309,1．721,2．761,1．411）;高密度脂蛋白胆固醇为HUA的保护因素（OR值为0．211）。结论HUA存在性别差异,且与血压、血脂密切相关。企业对职工的健康管理应充分考虑多危险因素的综合作用,全面的进行健康教育及干预。     

癌缺氧病因及预防和治疗

目的 探讨癌及安阳林州市食管癌高发原因及癌病因预防和治疗措施.方法 对林州市食管癌等疾病现场进行调查,在进行10余年统计分析基础上,综合分析了全国156篇文献成果.结果 提出癌缺氧病因学说,使用制氧机、按摩器、饮用纯净水治疗恶性肿瘤,取得良好效果,改水能够大幅降低林州市居民食管癌发病率、死亡率.结论 癌可能是由于机体长...     

Recruitment and retention challenges and successes

Objective: Addressing health disparities requires well designed, culturally adapted research. However, recruiting/retaining minority participants has often been challenging. We present strategies used to successfully recruit and retain rural Hispanic women during a breastfeeding education intervention.

Design: This study involved a two-group repeated measures quasi-experimental design with assessments at seven intervals between enrollment and 6 months postpartum. Participants (Hispanic women?≥?15 years old) were recruited through a regional hospital.

Results: We successfully met our recruitment goals, most women contacted were enrolled (46 of 58), and 100% completed the study.

Discussion: Research staff with ties within the community helped establish trust. Using bilingual study materials, simple language, and an interpreter addressed language/literacy concerns. Phone assessments facilitated participation as transportation was an issue. Accommodating requests to deliver or mail study materials and providing incentives were important. Extra effort was needed to maintain contact when phone service was disrupted or participants moved. Keys to success were persistence, flexibility, and alleviating barriers to participation.     

初产妇与经产妇焦虑抑郁状态分析及干预

目的：分析初产妇、经产妇心理状态特点,以便采取更有效的干预措施。方法筛选2014年6月至2015年1月在咸阳市旬邑县妇幼保健院产科门诊产前检查的健康初产和经产妇各60名,孕周为28~40周。入组时用焦虑自评量表( SAS)、抑郁自评量表(SDS)对两组孕妇进行心理评定,并给1次支持性心理干预(40~60分钟),1周后再次用SAS、SDS对两组孕妇进行评定分析。结果经产妇干预前SAS(50.73±3.45)、SDS(49.13±3.86)评分明显高于初产妇SAS(42.45±2.08)、SDS(41.77±2.21),差异均有统计学意义(t值分别为-15.921、-12.817,均P<0.01);干预后两组SAS、SDS评分均比干预前明显降低,差异均有统计学意义(t值分别为14.999、15.413;15.724、15.832,均P<0.01);干预后经产妇 SAS(38.61±5.02)、SDS(39.10±3.03)评分明显高于初产妇SAS(34.88±3.31)、SDS(32.01±4.27),差异均有统计学意义(t值分别为-4.805、-10.489,均P<0.01)。结论初产妇和经产妇均伴有焦虑、抑郁情绪,干预前后经产妇抑郁、焦虑情绪均较初产妇明显,支持性心理干预能有效改善孕妇的不良情绪。     

Continuity and change in neighborhood disadvantage and adolescent depression and anxiety

We used data from the Fragile Families and Child Wellbeing Study which includes a sample of adolescents of age 15 at the most recent wave (between 2014 and 2017) from mainly low-income urban families in the United States, to examine the association between neighborhood poverty entries and exits and adolescent depression and anxiety. In addition, we examined whether these associations differed by gender. Adolescents who consistently lived in disadvantaged neighborhoods had the highest level of depression and anxiety. Those who entered poor neighborhoods were more depressed than those who never lived in poor neighborhoods. Those who exited poor neighborhoods showed no significant difference in depression and anxiety compared to those never lived in poor neighborhoods. Furthermore, these associations applied to adolescent girls only and were not statistically significant for boys. The results suggest that neighborhood poverty has cumulative negative impacts on adolescent mental health and disproportionally affects adolescent girls. Reducing neighborhood poverty would substantially improve the health of adolescents, especially girls, which would reduce health disparities.     

Enabling positive change: Progress and setbacks in HIV and sexual and reproductive health and rights

At a point in history when the future of sexual and reproductive health including HIV looks particularly uncertain, it is helpful to recognise that many of the challenges currently faced are neither new nor insurmountable. Reflecting on past achievements and lessons learned helps us to have confidence that positive change is feasible. This paper reflects on some of the changes observed in countries like India and Mozambique and identifies a range of factors which need to coalesce to enable these developments, along with specific contextual factors. It is the combination of these influences rather than any one of them alone that brought about the change in the three instances described – fostering a positive political response to HIV in its early years in India; bringing about policy reform on abortion in Mozambique; and increasing contraceptive prevalence and age at marriage in some districts in Bihar, India. Change is always fragile and susceptible to setbacks, but change-seekers can learn in the process and gain renewed hope that progress can and often does take place if they persevere.     

儿童青少年超重肥胖评价方法及SPSS和SAS实现

超重肥胖已成为世界各国儿童青少年面临的重大公共卫生问题之一。现行的儿童青少年超重肥胖筛查标准不统一,逐条评价或自行编写程序容易出错且效率较低。本研究以中国学龄儿童青少年超重与肥胖筛查标准为例,详细介绍了国际和中国共四种评价儿童青少年超重肥胖的方法和步骤,结合具体案例详细介绍其应用方法,同时编制SPSS和SAS程序包和解...     

Car ownership and the association between fruit and vegetable availability and diet

Objective

Nearly all research on the food environment and diet has not accounted for car ownership — a potential key modifying factor. This study examined the modifying effect of car ownership on the relationship between neighborhood fruit and vegetable availability and intake.

Methods

Data on respondents' (n = 760) fruit and vegetable intake, car ownership, and demographics came from the 2008 New Orleans Behavioral Risk Factor Surveillance System. Shelf space data on fresh, frozen, and canned fruits and vegetables were collected in 2008 from a random sample of New Orleans stores (n = 114). Availability measures were constructed by summing the amount of fruit and vegetable shelf space in all stores within defined distances from respondent households. Regression analyses controlled for demographics and were run separately for respondents with and without a car.

Results

Fruit and vegetable availability was positively associated with intake among non-car owners. An additional 100 m of shelf space within 2 km of a residence was predictive of a half-serving/day increase in fruit and vegetable intake. Availability was not associated with intake among car owners.

Conclusions

Future research and interventions to increase neighborhood healthy food options should consider car ownership rates in their target areas as an important modifying factor.