红茶中黄曲霉毒素B_1的测定方法探讨

目的建立红茶中黄曲霉毒素B_1的测定方法。方法用60%乙腈-水提取茶叶中黄曲霉毒素B_1,经离心、稀释、过滤后通过免疫亲和柱,用甲醇将吸附在免疫亲和柱上的黄曲霉毒素B_1洗脱,洗脱液经光化学柱后衍生,通过带有荧光检测器的高效液相色谱仪定量分析。结果本方法检出限0.13μg/kg;线性范围0.5~20μg/L;相关系数r=0.999977;两种加标浓度平均回收率分别为85.0%和83.8%,相对标准偏差为分别为4.5%和3.2%。结论该方法消除了红茶中某些物质对免疫亲和柱吸附功能的干扰,具有简便、快捷、准确、灵敏度高和回收率好的特点,适用于红茶样品黄曲霉毒素B_1的检测。     

植物油中黄曲霉毒素B_1的污染状况调查分析

目的为了初步调查分析市售植物油中黄曲霉毒素B_1的污染状况。方法随机抽取市售花生油、玉米油、葵花籽油、菜籽油、大豆油、调和油共246份的植物油作为研究对象,采用高效液相色谱法进行黄曲霉毒素B_1测定。结果调查分析的6类植物油中,黄曲霉毒素B_1只在花生油和菜籽油中有检出,超标样品全部为花生油。花生油黄曲霉毒素B_1的平均含量为16.2μg/kg,最高浓度为288μg/kg,其检出率及超标率分别为88.1%和11.9%。散装花生油与定型包装花生油黄曲霉毒素B_1检出率差异无统计学意义(χ~2=0.649,P0.05);但超标率差异有统计学意义(χ~2=9.469,P0.05)。结论市售植物油黄曲霉毒素B_1的总体污染水平不高,但花生油的检出率和超标率较高,散装花生油较易受到黄曲霉毒素B_1的污染,其超标率高于定型包装花生油。     

超高效液相色谱法同时测定乳及乳饮料中黄曲霉毒素M_1和B_1

目的建立乳及乳饮料中黄曲霉毒素M_1和B_1的免疫亲和超高效液相色谱荧光检测器的测定方法。方法使用超细玻璃纤维滤纸过滤液态奶,滤液经免疫亲和柱净化富集,氮吹浓缩。C18柱(3.0 mm×50 mm×1.7μm)分离,甲醇乙腈水等度洗脱,萤光检测器定量检测。结果黄曲霉毒素M_1和B_1在(0.05~2.00)μg/L线性范围内,相关系数可达0.999。黄曲霉毒素M_1方法检出限为0.03μg/kg,黄曲霉毒素B_1方法检出限为0.20μg/kg。黄曲霉毒素M_1和B_1的回收率在71.1%~94%;精密度在3.2%~5.8%。结论该方法分离度好,分析数据速度快,准确度高,重复性好,适合乳及乳饮料中黄曲霉毒素M_1、B_1的测定。     

2014年成都市售常见香辛料霉菌及真菌毒素污染状况

目的调查成都市售常见香辛料中霉菌及重要真菌毒素污染状况,为控制该污染提供理论依据。方法 2014年3—9月以分层随机抽样法采集120份成都市农贸市场零售香辛料,按照GB 4789.15—2010《食品安全国家标准食品卫生微生物学检验》进行霉菌计数,酶联免疫反应试剂盒检测黄曲霉毒素B_1、黄曲霉毒素总量、赭曲霉毒素A及伏马菌素B_1含量。结果 120份香辛料的霉菌计数平均值为(8.4±1.5)×10~3CFU/g,仅3个样品霉菌总数<100 CFU/g。真菌毒素的检出范围分别是黄曲霉毒素B_1(相似文献   

免疫亲和柱净化-HPLC光化学柱后衍生荧光法测定植物油中的黄曲霉毒素

目的建立免疫亲和柱净化-HPLC光化学柱后衍生荧光检测法,用于测定植物油中黄曲霉毒素B_1、B_2、G_1、G_2。方法样品用乙腈-水(20+80,体积比)混合液提取,提取液经免疫亲和柱净化,净化液经C18色谱柱分离,用光化学柱后衍生器衍生、荧光检测器进行检测,采用外标法进行定量。结果在优化的条件下,4种黄曲霉毒素能达到很好的分离效果,黄曲霉毒素B_1、G_1在0.2~20.0 ng/ml范围内线性关系良好,检出限为0.04μg/kg;黄曲霉毒素B_2、G_2在0.1~10.0 ng/ml范围内线性关系良好,检出限为0.02μg/kg,4种黄曲霉毒素的回收率为82.5%~95.3%,RSD为2.4%~5.9%。结论该方法快速、简单、准确、灵敏、重现性好,是测定植物油中的黄曲霉毒素B_1、B_2、G_1、G_2的可靠方法。     

市售食品中黄曲霉毒素B_1、B_2、G_1、G_2污染情况分析

目的了解市售谷物、坚果和食用油等7类食品中的黄曲霉毒素B1、B2、G1、G2污染情况。方法建立高效液相色谱-串联质谱法检测黄曲霉毒素B_1、B_2、G_1、G_2。结果共检测266份样品,黄曲霉毒素的总检出率为4.5%,最高总含量为72.8μg/kg。在7类样品中,以花生油、玉米粉和花生受污染情况较为严重,其中,花生油的检出率为75.0%,明显高于其他类食品。所采集的266份样品黄曲霉毒素总检出率为:黄曲霉毒素B_1(4.5%)黄曲霉毒素G_1(0.8%)黄曲霉毒素B_2(0.4%)黄曲霉毒素G_2(0.0%)。4种黄曲霉毒素中以黄曲霉毒素B_1的污染情况最为严重,共检出1份花生样品含量为58.4μg/kg,为黄曲霉毒素B_1含量超标样品。结论黄曲霉毒素在食品中的污染情况仍然存在,相关管理部门应加强监控,以保证消费者的身体健康。     

食品中黄曲霉毒素限量标准中的成本-效益分析

目的通过成本-效益分析,探讨建立保护中国人群健康的合理的食品中黄曲霉毒素限量标准。方法利用传统数学模型方法和暴露限值(MOE)方法评估花生及其制品、玉米、大米中不同膳食总黄曲霉毒素和黄曲霉毒素B1限量标准下的健康影响,同时计算各限量水平下的食品损失。结果花生及其制品、玉米中总黄曲霉毒素、黄曲霉毒素B1限量水平的改变对减少我国人群肝癌患病数的作用没有显著差别,但不同的限量水平却可导致显著不同的食品损失。大米中总黄曲霉毒素、黄曲霉毒素B1限量水平的改变对减少我国人群肝癌患病数的作用以及导致的食品损失有较显著的影响。结论花生及其制品中总黄曲霉毒素20μg/kg、黄曲霉毒素B1 15μg/kg;玉米中总黄曲霉毒素20μg/kg、黄曲霉毒素B1 15μg/kg;大米中总黄曲霉毒素10μg/kg、黄曲霉毒素B1 5μg/kg或10μg/kg的限量标准比较合适。     

超高效液相色谱-大体积流通池荧光法检测食品中的4种黄曲霉毒素

目的建立具有大体积流通池的荧光检测超高效液相色谱法测定食品中4种黄曲霉毒素(B_1、B_2、G_1、G_2)的方法。方法食品经乙腈水提取液超声提取30 min,免疫亲和柱净化,氮气吹干,10%乙腈溶液定容,C_(18)反相色谱柱分离,采用具有大体积流通池的荧光检测器检测,激发波长为365 nm,发射波长为450 nm。结果 4种黄曲霉毒素在C_(18)高效液相色谱柱上得到了很好的分离,5 min内完成检测,方法的检出限为0.010μg/kg(黄曲霉毒素B_1、黄曲霉毒素G_1)和0.003μg/kg(黄曲霉毒素B_2、黄曲霉毒素G_2),平均回收率为77.55%~102.89%,RSD为1.2%~4.4%,4种黄曲霉毒素在0.1 ng/ml~10 ng/ml时线性关系良好(相关系数r0.999)。采用大体积流通池的荧光检测器后,灵敏度提高5倍~20倍。结论采用免疫亲和柱净化有效去除了基质中的杂质,改用大体积流通池的荧光检测器,省去了衍生步骤,简单快速,提高了黄曲霉毒素检测的灵敏度及准确度,适用于食品中黄曲霉毒素的测定。     

UPLC同时测定食品中黄曲霉毒素B1、B2、G1、G2

目的:建立免疫亲和柱超高效液相色谱法测定食品中黄曲霉毒素B1,B2,G1和G2含量的方法。方法:试样经过甲醇-水提取、稀释后经过免疫亲和柱层析净化,应用超高液相色谱法检测。结果:试验结果表明:空白样品分别按照0.2μg/kg、0.8μg/kg、2.0μg/kg添加黄曲霉毒素混合标准,回收率为75.0%～90.4%,精密度<5%,黄曲霉毒素B1,B2,G1和G2的检测灵敏度分别为0.2μg/kg,0.2μg/kg,0.4μg/kg,0.2μg/kg。结论:免疫亲和柱净化超高效液相色谱法测定食品中黄曲霉毒素B1,B2,G1,G2含量,是一种简单、快速和准确的方法。     

免疫亲和柱净化-酶联免疫吸附法检测普洱茶中黄曲霉毒素B_1

目的 建立普洱茶中黄曲霉毒素B1（AFB1）的免疫亲和柱净化-酶联免疫吸附检测方法。方法 粉碎后的普洱茶样品经三氯甲烷提取,水浴挥干后用甲醇-PBS溶解,样品液通过黄曲霉毒素B1免疫亲和柱净化洗脱,在450nm波长使用酶联免疫试剂盒（ELISA）定量检测黄曲霉毒素B1含量。结果 该方法在2.0~100.0μg/kg浓度范围内百分吸光率和浓度对数呈良好的线性关系,相关系数达0.999 8,样品最低检出限为1.0μg/kg,重复测定相对标准偏差为4.72%,3个水平（1.0、10.0、50.0μg/kg）的样品加标回收率为83.00%~104.90%。结论 本法具有简单、快速、高效等优点,适用于普洱茶复杂样品的AFB1定量检测。     

Trends in meningococcal disease in Italy in 1988

Meningococcal disease in Italy decreased 15% in 1988 from the previous year (290 vs. 342 cases). The decline was particularly evident in military cases (1.7/100,000 in 1988 vs. 5/100,000 in 1987) reflecting the full coverage of bivalent serogroup (A + C) meningococcal polysaccaride vaccine in army recruits, achieved since January 1988. The highest proportion of cases was seen in people older than 25 years of age (25%). Serogroup C constituted 60% of the isolates, while 19% belonged to serogroup B. The proportion of strains resistant to sulphonamides was 45%, while 15% were resistant to Minocycline and none to Rifampin. Out of the five military cases, only one (due to serogroup C) was attributable to the vaccine failure. A single coprimary case, but no secondary cases occurred among civilians. These findings are consistent with the trends reported in Italy in the previous years.     

Benzene in blood and phenol in urine in monitoring benzene exposure in industry

Determinations of benzene concentration in blood and of phenol in urine were made by head-space gas chromatography techniques on samples taken near the end of the work day from two groups of workers potentially exposed to low levels of benzene in the work-place atmosphere. Preliminary results suggest that benzene in blood is more reliable than phenol tests for assessing both exposure and uptake of benzene. Normal values of phenol in urine (10 mg/liter or less) were found in nearly all those cases in which benzene was detected in the blood.     

2015年郑州市饮用水放射性水平状况调查

目的了解郑州市不同地区、不同季节、不同水源类型的放射性水平。方法分别于丰水期和枯水期采集郑州市区黄河水源水、井水源水、丹江口水源水、出厂水和末梢水各一份;以县为单位,每单位采集出厂水、末梢水、水库水、河水、井水各1份,按《生活饮用水生活标准检验方法》(GB/T 5750.13-2006)检测饮用水中总α和总β放射性水平,依据《生活饮用水卫生标准》(GB 5749-2006)进行判定。结果丰水期、枯水期水体总α、总β放射性水平均低于国家标准限值。结论郑州市不同水源类型均处于正常的天然放射性本底水平。     

Occupational stress in nurses in psychiatric institutions in Taiwan

Nurses are known to be exposed to occupational stress. However, occupational stress is not well documented for nurses in psychiatric institutions in Taiwan. A cross-sectional study was conducted to explore the work-related stress and risk factors of nurses in psychiatric institutions in Taiwan. A structured questionnaire was distributed to nurses at five state-owned psychiatric hospitals in Taiwan in 2001. Demographic information, working environment, and personal health status were inquired. Occupational stress was assessed based on the Chinese version of Job Content Questionnaire (JCQ). General health status and mental health were evaluated by the International Quality of Life Assessment Short Form-36 (IQOLA SF-36). A total of 573 questionnaires were disseminated to nurses and 518 (90.4%) were satisfactorily completed by nurses, including 408 female full-time nurses who had been in their current work for more than 6 months. In the past one month, 17.2% of nurses reported being under significant stress often or always. Assault episodes were reported by 45.1% of nurses in the past 6 months. Among the nurses, 16.9%, 25.2%, 50.0%, and 7.8% belong to the "High strain", "Low strain", "Active", and "Passive" groups, respectively. Perceived occupational stress was associated with young age, widowed/divorced/separated marital status, high psychological demand, low workplace support, and threat of assault at work. Lower general health score was associated with low job control, high psychological demand, and perceived occupational stress. A lower mental health score was associated with low job control, high psychological demand, low workplace support, and perceived occupational stress. We concluded that nurses in psychiatric institutions are under significant stress related to work factors.     

Changes in nursing administration in supporting transplantation in Brazil

This historical and bibliographic study aimed to understand how Nursing was organized to support care in transplantation. The HISA, LILACS, BDENF, PERIENF and DEDALUS databases were consulted, and thirteen references were found, ten of which were scientific articles, two were master's dissertations and one was a doctoral thesis. The span of time chosen for study ranges from the date of the first kidney transplant in Brazil (1965), to the date of publication of the last scientific article found in the databases mentioned above (2003). After reading these articles, the ones that were similar in topic were grouped together, thus creating the thematic axis for the presentation of the results. The results showed that the Nursing profession has played an important and active role in transplants ever since the first procedure in 1965.     

2019年中国肿瘤流行病学研究进展

恶性肿瘤已成为中国居民的主要死因之一。近些年来,中国政府积极推进肿瘤预防和控制领域的研究工作,取得了很大的进步。本文简要汇总中国在肿瘤流行病学领域的研究进展,具体包括2019年的肿瘤负担、癌症危险因素及其干预、筛查和早期发现、癌症防治专项行动(2019-2022年)方案等方面,以期为我国肿瘤防治工作的有效开展提供技术支撑和理论依据。     

2012年绵阳市蔬菜中农药残留状况

目的 了解绵阳市2012年市售蔬菜中农药残留情况,为食用蔬菜监管提供依据.方法 全部样品均按照GB/T 5009-2003的方法进行农药的残留检测.依据GB 2763-2005《食品中农药最大残留限量》进行判定.结果 2012年共检测蔬菜165份,农药检出率和超标率分别为72.12％和23.64％.豆类、根茎类、叶菜类、瓜果菜类和食用菌类蔬菜检测农药残留超标率分别为8.00％、23.53％、36.00％、5.26％和27.03％,差异有统计学意义(x2=11.41,P＜0.01).不同种类农药超标率差异有统计学意义(x2 =62.42,P＜0.01).夏季和冬季蔬菜农药超标率差异无统计学意义(x2=3.44,P＞0.05).结论 绵阳市叶菜类蔬菜中农药残留情况较为严重,应采取有效措施,加强蔬菜的监督管理,从源头禁止高毒农药的使用,加大蔬菜种植、销售环节的监测,确保市民食用蔬菜的安全.