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The Effects of Dietary Restriction and Aging on in Vivo and in Vitro Binding of Aflatoxin B_1 to Cellular DNA

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Biomedical and Environmental Sciences 1991年第1期4卷 134-143页

作者： MING W.CHOU rex A.PEGRAM PU GAO S.R.HANSARD J.G.SHADDOCK D.A.CASCIANO National Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Center for Toxicological Research JeffersonNational Arkansas AR 72079 To whom repucsts for reprints should be addressed Arkansas AR 72079 US EPA HERL MD-74 Research Triangle Park NC 27711 Arkansas AR 72079 Arkansas AR 72079Arkansas AR 72079Center for Toxicological Research Jefferson Arkansas AR 72079

laboratory animals maintained on a reduced calorie but nutritionally adequate diet have extended life spans and lowered incidences of spontaneous and chemically induced cancers compared to ad libitum- fed counterparts. Many of the effects of dietary restriction on laboratory animals have been suggested to be related to a deceleration of the aging process. The inhibition of age-related changes in xenobiotic metabolizing enzyme activities by dietary restriction has previously been reported. Alterations of these enzyme activities may cause changes in metabolic activation of carcinogens and, therefore, carcinogen-DNA binding. DNA-repair capability has also been reported to be enhanced in diet-restricted rats. Using AFB1 as a model carcinogen, we have studied in vivo and in vitro hepatic AFB1 -DNA binding, demonstrating that dietary restriction (60% of ad libitum consumption) may decrease the metabolic activation of AFB1, and subsequently reduce AFB 1-DNA binding. Our preliminary results obtained from the AFB 1-DNA binding experiments in isolated hepatocytes suggest that the observed age-dependent reduction in AFB 1-DNA binding which may be attributed to a loss of metabolic activating capability was delayed in the diet-restricted rats.

关键词： The Effects of Dietary Restriction and Aging on in Vivo and in Vitro Binding of Aflatoxin B1 to Cellular DNA AFB

Assessing the Stress level among Medical Students in Rwanda

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Open Journal of Psychiatry 2022年第2期12卷 174-187页

作者： liberee Kubwimana Gislaine Mutatsineza lara Tesi rex Wong School of Medicine University of Global Health Equity Kigali Rwanda Bill and Joyce Cumming Institute of Global Health University of Global Health Equity Kigali Rwanda School of Public Health Yale University New Haven CT USA

Purpose: Many medical students suffered from some levels of emotional disturbances or disorders, causing negative physical and mental health problems, affecting performance academically, professionally, and personally. This study was conducted to assess the stress among medical students in Rwanda, in order to design appropriate strategies to address or prevent any related potential negative consequences. Method: Medical students who were enrolled in the two medical schools in Rwanda completed an online survey that was developed based on the Stress in Academic life Scale (SAlS). The SAlS has 27 4-point likert scale questions assessing stress related to social support, motivation, curriculum and teaching, academic ambition, self-confidence, performance anxiety, and career. One open-ended question was also included for respondents’ comments. The SAlS scores were categorized into “no to fairly”, “fairly to very” and “very to severely” stress levels. Results: A total of 137 samples responded. The overall median SAl score was 1.22, with over 54% of the respondents reported experiencing fairly to severe levels of stress. The highest stress levels were related to Curriculum and Teaching (median = 1.5), Self-confidence (median = 1.33), and Motivation (median = 1.33). The stress score was found to be negatively correlated to age (r = -0.205, P = 0.02), and the number of years in the program (r = -0.218, P = 0.01), and associated with receiving government funding (P = 0.01). lack of financial support, lack of support from instructors, and disorganized academic activities were also reported as sources of stress. Conclusion: The results of this study suggested mild to moderate levels of stress were faced by the medical students in Rwanda. Finance plays a role, but the main stressors stemmed from the curriculum, teaching, and administrative organization. Medical schools should proactively create appropriate interventions to improve students’ physical and psychological well-being

关键词： Medical Student Stress SAlS Mental Health Rwanda

Genomewide selection for fruit quality traits in apple: breeding insights gained from prediction and postdiction

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Horticulture Research 2023年第6期10卷 238-249页

作者： Sarah A.Kostick rex Bernardo James J.luby Department of Horticultural Science University of MinnesotaSaint PaulMN 55108USA Department of Agronomy and Plant Genetics University of MinnesotaSaint PaulMN 55108USA

Many fruit quality traits in apple(Malus domestica Borkh.)are controlled by multiple small-effect quantitative trait loci(QTls).Genomewide selection(genomic selection)might be an effective breeding approach for highly quantitative traits in woody perennial crops with long generation times like *** goal of this study was to determine if genomewide prediction is an effective breeding approach for fruit quality traits in an apple scion breeding *** apple scion breeding germplasm(nindividuals=955),high-quality single nucleotide polymorphism(SNP)data(nSNPs=977),and breeding program fruit quality trait data at harvest were *** parents‘Honeycrisp’and‘Minneiska’were highly *** to high predictive abilities were observed for most fruit quality traits at *** example,when 25%random subsets of the germplasm set were used as training sets,mean predictive abilities ranged from 0.35 to 0.54 across ***,training and test sets,family size for within family prediction,and number of SNPs per chromosome affected model predictive *** of large-effect QTls as fixed effects resulted in higher predictive abilities for some traits(*** red overcolor).Postdiction(***)analyses demonstrated the impact of culling threshold on selection *** results of this study demonstrate that genomewide selection is a useful breeding approach for certain fruit quality traits in apple.

关键词： breeding germplasm crops

Study on the one-bath dyeing of wool/PTT blends （Part Ⅱ）

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Study on the one-bath dyeing of wool/PTT blends （Part Ⅱ）

玛雅神圣球赛和古典时期韦拉克鲁斯关系的几点研究

2006中国国际毛纺织会议暨IWTO羊毛论坛

作者： P.rex Brady Centre for Material an1d Fibre Innovation Deakin University Geelong Victoria 3217 Australia

This paper is the second part of a series on the dyeing of blends of polytrimethylene terephthalate （PTT） staple and wool. The compatibility between Terasil disperse dyes and lanasol reactive dyes in the same dye bath, the effects of processing parameters such as pH, temperature and the rate of temperature increase on union dyeing of PTT and wool were also examined. The degree of damage to wool fibres at different dyeing temperatures （with and without dyes） was measured using an Australian standard testing method for alkali solubility. The results have shown that most Terasil disperse dyes achieved the highest dye-uptake on PTT staple at 110℃;Terasil dyes and lanasol dyes showed good compatibility in one-bath dyeing under weak acid conditions at temperatures lower than 120℃. An optimised dyeing technique was developed which minimized the staining problem of Terasil disperse dyes on wool and gave stable union-dyed wool/PTT blended products with higher colour fastness, and lower damage to wool than encountered with normal wool/PET blend dyeing processes.

关键词： wool PTT one bath dyeing compatibility staining alkali-solubility of wool

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世界宗教文化 2012年第4期 25-32页

作者： rex Koontz 李金花美国休斯顿大学艺术学院中国社会科学院世界宗教研究所

在古代墨西哥和危地马拉所有民族中都存在一种作为运动和宗教祭祀的橡胶球赛。这种球赛的祭祀功能在古典时期的玛雅人以及他们在墨西哥湾的近邻中十分重要。本论文对比论述古典时期的玛雅和韦拉克鲁斯地区的一些很可能与球赛相关的宗教... 详细信息

在古代墨西哥和危地马拉所有民族中都存在一种作为运动和宗教祭祀的橡胶球赛。这种球赛的祭祀功能在古典时期的玛雅人以及他们在墨西哥湾的近邻中十分重要。本论文对比论述古典时期的玛雅和韦拉克鲁斯地区的一些很可能与球赛相关的宗教活动。论述的重点是跟球赛相关的一种雕刻器物——"轭"——它在两个文化区域的共同点、它作为重要身份地位的标记和它的宗教形象的来源。论文还讨论两个不同文化区域在轭"的材料选用以及宗教形象方面的一些重要的区别,以明确各自文化是如何把球赛当作一项最基本的宗教祭祀来实施的。

关键词：玛雅韦拉克鲁斯宗教祭祀玛雅球赛身体防护器

Exploring the Perspectives of Healthcare Providers on Providing HIV Prevention and Treatment Services for Key Populations in Rwanda: A Qualitative Study

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World Journal of AIDS 2022年第2期12卷 120-139页

作者： Gloria Igihozo Junious Mabo Sichali Sandip Medhe rex Wong Bill and Joyce Cummings’ Institute of Global Health University of Global Health Equity Kigali Rwanda School of Public Health Yale University New Haven CT USA

Background: The overall HIV prevalence and incidence in Rwanda have decreased significantly in the past decade. However, opposite trends are seen among key populations (KP). The HIV prevalence among sex workers is as high as 51% and continues to rise. While the HIV prevalence among KP remains high, their adherence to treatment is low. Healthcare providers play a vital role in KP’s access and adherence to HIV treatment. This study aimed to explore the perspectives of healthcare providers on providing HIV services to key populations in Rwanda. Methods: An exploratory qualitative study was conducted with nurses, doctors, social workers, and psychologists who provide HIV services to KP in public health facilities in Rwanda. In-depth interviews were conducted using a semi-structured interview guide. All data were analyzed thematically using Dedoose. Results: Interviews were conducted with 18 healthcare providers. Three overarching themes emerged from the interviews: healthcare providers’ intrinsic feelings affect the ways they provide HIV services to key populations, key populations face a multitude of challenges related to accessing treatment and preventing the spread of HIV, and a more comprehensive and sensitive approach should be used to improve HIV services for key populations. Conclusion: Healthcare providers expressed difficulties in providing services to key populations and identified a lack of adherence to treatment and prevention guidelines, structural barriers, KP’s lack of trust in the healthcare system, and the discrimination and abuse KP face as challenges to effective HIV prevention and treatment. More comprehensive services including clinical, financial, and psychosocial support from trusted sources are needed. Some important policy changes are essential to facilitate access to HIV services for KP.

关键词： HIV/AIDS Key Populations Sex Workers Men Who Have Sex with Men Health Services

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母牛指数的计算

草食家畜 1987年第1期 17-18页

作者： rex l.Powell ,张玲

母牛指数是对母牛遗传能力的估计。对各种性状都可以计算其母牛指数。本文仅就产奶量母牛指数作一介绍。饲养管理对产奶量的影响远远大于遗传因素,因此在计算母牛指数时还要考虑同龄母牛的双亲,以调节同龄母牛的遗传水平。为了计算遗... 详细信息

母牛指数是对母牛遗传能力的估计。对各种性状都可以计算其母牛指数。本文仅就产奶量母牛指数作一介绍。饲养管理对产奶量的影响远远大于遗传因素,因此在计算母牛指数时还要考虑同龄母牛的双亲,以调节同龄母牛的遗传水平。为了计算遗传值,要根据一些影响因素(主要是泌乳期长度和同龄牛头数)对母牛产奶记录进行加权处理。同龄母牛的记录也要进行加权。

关键词：母牛双亲产奶量产乳量泌乳期乳脂量重复力重复率选择偏差公牛产犊

灭鼠剂适口性衡量标准研究——维生素D_3和磷化锌的适口性比较

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兽类学报 1990年第2期10卷 151-155页

作者：李镜辉 rex E.Marsh 中国预防医学科学院流行病学微生物学研究所美国加利福尼亚大学Davis分校野生和水生动物生物学系

本文提出了一种新的评价灭鼠剂适口性的方法,即用直线回归方程来描述灭鼠剂的适口性,具体做法是以毒饵的摄食系数为纵座标(Y),以灭鼠剂在毒饵中的浓度的对数为横座标(X),求出直线回归方程。本法的优点是可以反映毒饵的适口性随灭鼠剂在... 详细信息

本文提出了一种新的评价灭鼠剂适口性的方法,即用直线回归方程来描述灭鼠剂的适口性,具体做法是以毒饵的摄食系数为纵座标(Y),以灭鼠剂在毒饵中的浓度的对数为横座标(X),求出直线回归方程。本法的优点是可以反映毒饵的适口性随灭鼠剂在毒饵中的浓度改变而产生变化的趋势,并以磷化锌和维生素D_3为实例加以说明。相关系数测定表明,磷化锌的摄食系数与其对数浓度之间存在着非常显著的负相关关系(r=-0.8923,p<0.001),其直线回归方程为Y=0.4153-0.2541x。实验结果表明,磷化锌的最低适用浓度和最适浓度均为2％,而维生素D_3的最低适用浓度为0.1％,最适浓度为0.2％。

关键词：灭鼠剂适口性维生素D3 磷化锌

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通过国际联合委员会认证保证临床检验质量

中华检验医学杂志 2006年第9期29卷 854-856页

作者：孙芾王厚芳 rex Hancock 北京和睦家医院医学检验中心 100016 北京和睦家医院质量安全部 100016

北京和睦家医院是一所中美合作的综合性国际医院，2006年申请了国际联合委员会（Joint Commission International，JCI）组织的医院体系认证，医院及其在北京的两个诊所一并于2005年9月1日正式通过了JCI认证。为使更多的同道了解JCI医... 详细信息

北京和睦家医院是一所中美合作的综合性国际医院，2006年申请了国际联合委员会（Joint Commission International，JCI）组织的医院体系认证，医院及其在北京的两个诊所一并于2005年9月1日正式通过了JCI认证。为使更多的同道了解JCI医院认证标准，规范管理提高服务水平，现将我科进行JCI认证准备方法和认证经验做以介绍。

关键词：国际医院体系认证联合委员会检验质量临床和睦家医院 JCI 中美合作