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胎儿血浆睾丸酮浓度与肾上腺皮质激素正相关

世界核心医学期刊文摘（儿科学分册） 2005年第8期1卷 19-20页

作者： Gitau R. Adams D. Fisk N.M. glover v. 朱新菊 Wolfson/Weston Res. Ctr. Fam. Hlth. Inst. of Repro. and Devmtl. Biology Imperial College London Du Cane Road London W12 0NN United Kingdom Prof.

Background: Fetal exposure to testosterone has been implicated in programming childhood behav.our, but little is known about the determinants of fetal testos terone concentrations. Aims: To inv.stigate the relation between fetal testoster one and maternal and fetal cortisol. Methods: Clinically indicated blood samples taken from 44 human fetuses (mean gestational age 27 weeks, range 15- 38), tog ether with paired maternal samples, were analysed for testosterone and cortisol concentrations. Results: Male fetuses had significantly higher concentrations of testosterone than females. Female but not male fetal concentrations rose signif icantly with gestational age. Fetal testosterone correlated positiv.ly with both fetal cortisol and maternal testosterone concentrations. Multiple regression sh owed that maternal testosterone and fetal cortisol were independently correlated with fetal plasma testosterone in both sexes. Conclusion: Unlike the norm in th e adult, where testosterone production is often inhibited by cortisol, in the fe tus there is a positiv. link between the two.

关键词：胎儿血睾丸酮男性胎儿多重回归分析平均胎龄临床指征行为发育

玉米籽粒发育过程中胚乳核DNA含量的变化同籽粒性状的关系

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作物学报 1994年第1期20卷 46-51页

作者：高群英 D.v.glover 中国农业科学院作物育种栽培研究所北京100081 美国普渡大学

用双波长(550,488nm)显微分光光度法测定籽粒发育时期不同Su2基因剂量(0-3)玉米杂交种(Mo_(17)×B73)胚乳核的DNA含量.结果表明:单个胚乳核的DNA含量在授粉后第8天是3.0-4.6C,10天以后迅速上升,20-22天达到高峰,为48.9-63.9C,然后下降.... 详细信息

用双波长(550,488nm)显微分光光度法测定籽粒发育时期不同Su2基因剂量(0-3)玉米杂交种(Mo_(17)×B73)胚乳核的DNA含量.结果表明:单个胚乳核的DNA含量在授粉后第8天是3.0-4.6C,10天以后迅速上升,20-22天达到高峰,为48.9-63.9C,然后下降.年份间DNA含量差异显著(P≤0.05).在籽粒发育过程中,胚乳核DNA含量与籽粒重量和体积显著相关(r=O.7738,0.8369,P≤0.01).胚乳细胞中Su_2基因的数量水平对胚乳核DNA含量没有剂量效应.

关键词：玉米胚乳核 DNA 籽粒性状

2024 Adult Compendium of Physical Activ.ties:A third update of the energy costs of human activ.ties

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Journal of Sport and Health Science 2024年第1期13卷 6-12页

作者： Stephen D.Herrmann Erik A.Willis Barbara E.Ainsworth Tiago v.Barreira Mary Hastert Chelsea L.Kracht John M.Schuna Jr. Zhenghui Cai Minghui Quan Catrine Tudor-Locke Melicia C.Whitt-glover Dav.d R. Jacobs Jr. Kansas Center for Metabolism and Obesity Research University of Kansas Medical CenterKansas CityKS 66160USA Div.sion of Physical Activ.ty and Weight Management Department of Internal MedicineUniversity of Kansas Medical CenterKansas CityKS 66160USA Center for Health Promotion and Disease Prev.ntion University of North Carolina at Chapel HillChapel HillNC 27599USA College of Health Solutions Arizona State UniversityPhoenixAZ 85003USA School of Exercise and Health Shanghai University of SportShanghai 200438China Exercise Science Department Syracuse UniversitySyracuseNY 13244USA Clinical Sciences Div.sion Pennington Biomedical Research CenterBaton RougeLA 70808USA School of Exercise and Sport Science Oregon State UniversityCorvallisOR 97331USA College of Health and Human Serv.ces University of North Carolina at CharlotteCharlotteNC 28223USA Gramercy Research Group KnightdaleNC 27545USA Div.sion of Epidemiology and Community Health School of Public HealthUniversity of MinnesotaMinneapolisMN 55454USA

Background:The Compendium of Physical Activ.ties was published in 1993 to improv. the comparability of energy expenditure v.lues assigned to self-reported physical activ.ty(PA)across *** original v.rsion was updated in 2000,and again in 2011,and has been widely used to support PA research,practice,and public health ***:This 2024 update was tailored for adults 19-59 years of age by remov.ng data from those≥60 *** a systematic rev.ew and supplementary searches,we identified new activ.ties and their associated measured metabolic equiv.lent(MET)v.lues(using indirect calorimetry)published since *** replaced estimated METs with measured v.lues when ***:We screened 32,173 abstracts and 1507 full-text papers and extracted 2356 PA energy expenditure v.lues from 701 *** added303 new PAs and adjusted 176 existing MET v.lues and descriptions to reflect the addition of new data and remov.l of METs for older *** added a Major Heading(v.deo Games).The 2024 Adult Compendium includes 1114 PAs(912 with measured and 202 with estimated v.lues)across 22 Major ***:This comprehensiv. update and refinement led to the creation of The 2024 Adult Compendium,which has utility across research,public health,education,and healthcare domains,as well as in the dev.lopment of consumer health *** new website with the complete lists of PAs and supporting resources is av.ilable at https://***.

关键词： Adults Energy expenditure Exercise MET Physical Activ.ties

Ev.luation of the cracking and aging susceptibility of asphalt mixtures using v.scoelastic properties and master curv. parameters

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Journal of Traffic and Transportation Engineering(English Edition) 2022年第1期9卷 106-119页

作者： Runhua Zhang Jo E.Sias Eshan v.Dav. Department of Civ.l and Env.ronmental Engineering University of New HampshireDurhamNH 03824USA

Aging can significantly affect the performance of asphalt mixtures, causing increase in stiffness, reduction in relaxation capability and increase in cracking susceptibility. It is also well known that fundamental v.scoelastic properties are used for design and modelling of asphalt mixtures and pav.ment structures to addressing rutting, fatigue and thermal cracking concerns. The objectiv. of this paper is to study how the v.scoelastic properties of asphalt mixture change ov.r time, and ev.luate and identify the cracking and aging susceptibility of asphalt mixtures with different mix v.riables during material selection and mixture design. Ten mixtures are ev.luated using different laboratory conditioning protocols to simulate a range of aging lev.ls in the field. The complex modulus test is then conducted on the lab aged mixtures to measure the v.scoelastic properties in order to construct the dynamic modulus and phase angle master curv.s. The mixture glover-Rowe(G-Rm) parameter and the shape parameters of the dynamic modulus and phase angle master curv.s, including inflection point frequency(-β/γ), difference between the glassy modulus and the inflection point modulus(γ), peak v.lue of phase angle(a) and the horizontal position(frequency) of the peak phase angle v.lue(c), are determined and ev.luated for the mixtures with different aging conditions and mix v.riables. The study indicates the ability of the G-Rmparameter and all the master curv. shape parameters to capture the effect of different aging conditions on linear v.scoelastic mixture properties, as well as the cracking and aging susceptibility of asphalt mixtures.

关键词： Asphalt mixture v.scoelastic properties Complex modulus and phase angle master curv. Master curv. shape parameters Aging susceptibility Cracking susceptibility

N沉积物与玉米产量的关系和三个玉米杂交种对氮的反应

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贵州农业科学 1985年第5期 53-57页

作者： C.Y.Tsai D.M.Huber D.v.glover H.L.Warren 胡建华贵州农科院

三个玉米（Zea mays L.）杂交种,春施不同量的固态氮肥,测算其籽粒产量。于玉米中丝期和授粉后6O天,分析其营养组织和籽粒的含氮量,试验的三个杂交种中,B14×OH43（中间类型）能适应中量的氮肥;B73×MO17（高肥类型）对增施氮肥有显著... 详细信息

三个玉米（Zea mays L.）杂交种,春施不同量的固态氮肥,测算其籽粒产量。于玉米中丝期和授粉后6O天,分析其营养组织和籽粒的含氮量,试验的三个杂交种中,B14×OH43（中间类型）能适应中量的氮肥;B73×MO17（高肥类型）对增施氮肥有显著的感应;先锋3732（低肥类型）在低肥用量下生长良好,且每公顷仅施用67公斤N即达到其最高产量。至少有三种因素影响玉米产量,这些因素能使玉米低肥型与高肥型相区别,它们是:1)在中丝期以后对增施氮肥的吸收能力;2)籽粒充实的速度和持续的时间;3)受氮肥影响的玉米醇蛋白合成（谷粒氮库）的速率、当先锋3732籽粒的基因型由于用B73×MO17的花粉授粉改善后,发育着的F1代籽粒其谷粒蛋白质浓度不仅比先锋3732F2代的籽粒中的要高,而且对其双亲具有干物质积累的补充的动力,由于这种补充作用,得到了大于这两个杂交种自交时的籽粒。表明谷粒库在影响玉米粒重和籽粒产量方面比营养源更为重要。

关键词：玉米栽培种(Zea maysL.) 氮肥籽粒充实玉米醇蛋白蛋白质