水中三氯甲烷及四氯化碳的顶空毛细柱气相色谱测定法

目的：提高测定生活饮用水中微量三氯甲烷和四氯化碳的方法的灵敏度和分离度。方法：采用顶空毛细柱气相色谱法取代传统的顶空填充柱法测定生活饮用水中微量的三氯甲烷和四氯化碳。结果：三氯甲烷、四氯化碳的最小检出限分别为0．10μg／L和0．010μg／L，准确度和精密度均符合检验的要求。结论：顶空毛细柱气相色谱法测定水中三氯甲烷、四氯化碳，操作简单快捷，且灵敏度和分离度高于传统的顶空填充柱法。     

水中三氯甲烷和四氯化碳顶空气相色谱法测定

目的：研究顶空气相色谱法测定水中三氯甲烷和四氯化碳的方法。方法：利用三氯甲烷、四氯化碳在水中的弱溶解性，采用微池电子捕获检测器顶空气相色谱法测定。结果：在测定条件下，方法的检出限三氯甲烷为0．10mg／L，四氯化碳为0．01μg／L；三氯甲烷的RSD1．7％～4．1％，四氯化碳的RSD1．18％～2．44％；回收率三氯甲烷为99．0％～103％，四氯化碳为99．2％～102％。结论：该方法具有灵敏度高、分析简便快速等特点。样品测定结果满意。     

饮用水中三氯甲烷和四氯化碳的顶空气相色谱测定法

目的建立测定饮用水中了氯甲烷和四氯化碳含量的顶空毛细管柱气相色谱法,同时考察不同来源饮用水中氯仿和四氯化碳的分布状况、方法采用顶空自动进样技术,用特异性DB-624毛细管柱气相色谱法测定水中三氯甲烷和四氧化碳。结果标准曲线的相关系数为〉0.999,相对标准偏差为1.5％-8.3％,三氯甲烷、四氯化碳的平均回收率为97.5％-103.3％;三氯甲烷的线性范围为2.0-10.0μg／L,检出限为0.02μg／L;四氯化碳线性范同为1.0-5.0μg／L,检出限为0.003μg／L。结论该方法简便、快速,具有较好的精密度与准确度,可用于水中三氯甲烷、四氯化碳的测定。     

气相色谱法测定饮用水中挥发性卤代烃的不确定度评定

目的建立自动顶空毛细柱气相色谱法测定饮用水中三氯甲烷、四氯化碳、二氯一溴甲烷、一氯二溴甲烷、三溴甲烷等挥发性卤代烃的不确定度评定方法,以评定测量结果的质量。方法根据GB／T5750．8—2006（（生活饮用水标准检验方法》建立数学模型,逐一分析量化测量过程中的不确定度分量,计算合成标准不确定度和扩展不确定度。结果三氯甲烷含量为5．88μg／L时,U=0．42μg/WL,k=2;四氯化碳含量为1．98μg/L时,U=0．18μg/E,％=2;二氯一溴甲烷含量为12．60μg/L时,U=0．72μg/WE,k=2;一氯二溴甲烷含量为6．00μg/WL时,U：0．36μg/L,k=2;三溴甲烷含量为5．55μg／L时,U=0．38μg/WE,％=2。结论曲线拟合和标准溶液带来的不确定度是测量结果不确定度的主要来源,此方法适用于饮用水中挥发性卤代烃的不确定度评定。     

毛细柱——微电子捕获气相色谱法测定水中氯仿、四氯化碳

毛细柱－微电子捕获气相色谱法水中氯仿，四氯化碳，其线性范围得到扩延，氯仿浓度在0－10μg/L范围内，相关系数r=0.9910，回归方程Y＝1．959X＋4．816，最低检出学为0．1032μg/L，四氯化碳浓度在0－1μg/L，范围内，相关系数r=0.9970，回归方程Y＝3．947X＋42．579，最低检出浓度为0．01219μg/L。同时，本方法简化了操作过程，方法灵敏度得到较大提高，并且准确度和精密度均符合检测要求。     

环境样品中乙草胺和莠去津的气相色谱-质谱测定法

目的探讨环境样品中乙草胺和莠去津的气相色谱-质谱测定法。方法使用全自动固相萃取仪(包括大剂量型和小剂量型)对土壤和地面水样品分别进行萃取和富集。采用气相色谱-质谱联用法(EI源)对处理后的样品进行测定,采用多级质谱扫描方式同时对环境样品中乙草胺和莠去津进行定量分析。结果该方法的相对标准偏差为1．73％-8．31％;方法回收率为79．2％-95．1％;乙草胺在水中最小检出浓度为0．1μg／L,在土壤中最小检出含量为0．005mg／kg;莠去津在水中最小检出浓度为0．05μg／L,在土壤中最小检出含量为0．0025mg／kg。线性范围均为0-5μg／ml。结论该方法可用于环境样品中乙草胺和莠去津残留量的测定。     

气相色谱-质谱联用法测定饮用水中邻苯二甲酸酯类物质

[目的]建立一种测定饮用水中邻苯二甲酸酯的气相色谱质谱方法。[方法]饮用水中邻苯二甲酸酯被二氯甲烷萃取，萃取液浓缩后进行气相色谱-质谱分析，以选择离子监测方式分析，定量则以同位素内标法测定。[结果]邻苯二甲酸二甲酯、邻苯二甲酸二乙酯、邻苯二甲酸二丁酯、邻苯二甲酸二（2-乙基己基）酯、邻苯二甲酸二正辛酯的线性范围分别为50-400μg／L、50～400μg／L、50-400μg／L、200～1600μg／L、200～1600μg／L，相关系数均在0．99以上，低、高2种浓度加标回收率均在78．2％～92．5％之间，相对标准偏差均小于10％，5种邻苯二甲酸酯的最低检出浓度分别为0．1μg／L、0．1μg／L、0．1μg／L、0．3μg／L、0．3μg／L。对20份饮用水进行了测定，20份水样均检出了邻苯二甲酸二丁酯，其中11份水样检出了邻苯二甲酸二（2-乙基己基）酯。[结论]方法适合于饮用水中邻苯二甲酸酯的测定。     

工作场所空气中1,2-二氯乙烷、三氯甲烷、四氯化碳的时间加权平均浓度测定方法研究

目的 建立工作场所空气中卤代烷烃类化合物1,2-二氯乙烷、三氯甲烷、四氯化碳的时间加权平均浓度（TWA）气相色谱测定方法。方法 通过活性炭管采样,溶剂解吸气相色谱法测定空气中卤代烷烃类化合物1,2-二氯乙烷、三氯甲烷、四氯化碳。按照《工作场所空气中毒物检测方法研究规范》的要求进行实验研究,并对其测定条件和气相色谱条件进行优化选择。结果 方法线性范围：1,2-二氯乙烷为20～500μg／ml,三氯Eft烷为90～800μg／ml,四氯化碳为90～500μg／ml。相关系数介于0、9996～0．9999。检出限：1,2-二氯乙烷为20μg／ml,三氯甲烷为90μg／ml,四氯化碳为90μg／ml,相对标准偏差为0．7％～6．4％。每100mg活性炭对1,2-二氯乙烷、三氯甲烷、四氯化碳的穿透容量分别为30．1,32．1,32．0mg。样品在活性炭管中至少可稳定7d,方法重现性好。结论此方法的各项检测指标均达到了工作场所空气中毒物检测方法研究规范的要求,适用于工作场所空气中卤代烷烃类化合物1,2-二氯乙烷、三氯甲烷、四氯化碳的时间加权平均浓度测定。     

顶空气相色谱法测定饮用水中的三氯甲烷及四氯化碳

目的 建立同时测定生活饮用水中三氯甲烷、四氯化碳含量的顶空毛细管柱气相色谱方法.方法 采用顶空自动进样技术,用毛细管柱气相色谱法测定饮用水中微量的三氯甲烷、四氯化碳含量.以保留时间定性,峰面积外标法定量.结果 该方法实现了两种消毒副产物的同时分析测定,灵敏度高、线性范围宽、检出限低,三氯甲烷在0～72.0μg/L浓度范...     

环境水样中银的火焰原子吸收分光光度测定法

水中银的分析方法国家标准采用石墨炉原子吸收法分析水中微量、痕量银，本文使用国产WFX-120型原子吸收分光光计，采用火焰法分析环境水样中微量银。其方法的最低检测限达到了2．0μg／L、特征浓度为25．0μg／L，分别低于国家卫生标准25和2倍，与文献报道的火焰法分析银的检测限(10     

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.