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缺乏叶酸培养基中自发及诱发的染色体畸变

Journal of Genetics and Genomics 1984年第4期 318-324页

作者：周宪庭,johna.reidy,陈达能中国科学院遗传研究所美国卫生部疾病控制中心遗传实验室美国卫生部疾病控制中心遗传实验室北京

在缺乏叶酸的基本培养基中,淋巴细胞染色体对环境因子有更高的敏感性,结果表明这个体系可能用于检测环境有害因子对人体的影响。

关键词：染色体畸变基本培养基脆性位点 FA 叶酸蝶酰谷氨酸维生素B MEM 染色体染色体断裂双着丝点细胞

Genetically Engineered Corn Rootworm Resistance: Potential for Reduction of Human Health Effects From Pesticides

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Biomedical and Environmental Sciences 2003年第1期16卷 17-28页

作者： FREDERICKW.OEHME johna.PICKRELL Comparative Toxicology Laboratories 1800 Denison AvenueMosier HallKansas State UniversityManhattanKS 66506-5705 USAComparative Toxicology Laboratories1800 Denison AvenueMosier HallKansas State UniversityManhattanKS 66506-5705 USA

Objective and Methods Insecticide use, grower preferences regarding genetically engineered (GE) corn resistant to com rootworm (CRW), and the health effects of using various CRW insecticides (organophosphates, pyrethroids, fipronil and carbamates) are reviewed for current and future farm practices. Results Pest damage to corn has been reduced only one-third by insecticide applications. Health costs from insecticide use appear significant, but costs attributable to CRW control are not quantifiable from available data. Methods reducing health-related costs of insecticide-based CRW control should be evaluated. As a first step, organophosphate insecticide use has been reduced as they have high acute toxicity and risk of long-term neurological consequences. A second step is to use agents which more specifically target the CRW. Conclusion Whereas current insecticides may be poisonous to many species of insects, birds, mammals and humans, a protein derived from Bacillus thurigiensis and produced in plants via genetic modification can target the specific insect of CRW (Coleoptra), sparing other insect and non-insect species from injury.

关键词： Genetically engineered corn Corn rootworm resistance Insecticide toxicity Pest damage control Health costs

新西兰霍克湾普卡瓦湖岩芯植硅体分析所揭示的火山喷发事件后的植被变化(英文)

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古生物学报 2003年第1期42卷 68-75页

作者： johna.CARTER 新西兰惠灵顿维多利亚大学地球科学学院

含火山灰层沉积的植硅体分析为了解植被对从空中下降的火山灰的反应提供新的信息。新西兰霍克湾的一个深197m钻孔的上部50 m样品,提供了距今约50ka以来连续的植被记录。植硅体组合在4个主要的火山灰层都发生了明显的变化,表现在树木和... 详细信息

含火山灰层沉积的植硅体分析为了解植被对从空中下降的火山灰的反应提供新的信息。新西兰霍克湾的一个深197m钻孔的上部50 m样品,提供了距今约50ka以来连续的植被记录。植硅体组合在4个主要的火山灰层都发生了明显的变化,表现在树木和灌木的急剧下降及禾草类和莎草科的繁盛。在每次火山灰降落后,都会有一系列的继后变化,木本类最早死亡,禾草类和莎草科取而代之,并很快占据裸露的地表。经过一个相当长的滞后时间,树木和/或灌木重新替代草本和莎草科。

关键词：植硅体新西兰霍克湾火山灰层沉积古环境晚第四纪植被变化

巴拿马盆地深海钻井区的速度结构——薄洋壳的证据

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地球物理学进展 1990年第4期5卷 25-42页

作者： johna.Collinsl 华章

我们对巴拿马盆地深海钻井计划504B场区广角反射/折射数据进行了分析.目前,最深的钻孔已钻入大洋地壳1.288 km.数据用一个1785立方英寸的气枪台阵和固定增益的声纳浮标接收器采集,资料包括沿三个不同方位放炮的四条相交的地震剖面,同时... 详细信息

我们对巴拿马盆地深海钻井计划504B场区广角反射/折射数据进行了分析.目前,最深的钻孔已钻入大洋地壳1.288 km.数据用一个1785立方英寸的气枪台阵和固定增益的声纳浮标接收器采集,资料包括沿三个不同方位放炮的四条相交的地震剖面,同时采集的垂直入射和多道地震反射数据.最大距离远达30km内的观测P波、S波为中地壳、下地壳的速度结构以及总的地壳厚度提供了约束.比较所有四个剖面上P、S波走时与振幅,揭示了用反射合成地震图方法进行模拟的重要的相似性.正演结果表明,与标准的大洋速度模型相反,一个能较好地解释观测数据的速度深度剖面的特征是,中地壳具有高速度梯度(达0.6 km/s/km);近莫霍面上方有一个1.8km厚的低速带(V_r=7.1—6.7km/s);总地壳厚度只有5 km.中地壳高速度梯度的解释受到16—19 km内P波振幅聚焦的约束.虽然S波波至不如P波波至发育得那么好,但它也表现出相似的聚焦性.总的地壳厚度要受到有关P波、16—28 km内观测到的广角反射以及地壳走时为1.4—1.5 s的MCS反射信号综合解释的约束.虽然这些信号之间没有直接的关系,但其走时与两者具有共同的起因的假设是一致的.广角反射的振幅模拟表明:这些信号都在莫霍面产生.

关键词：广角反射速度结构地壳厚度速度深度剖面速度模型合成地震图深海钻井低速带地震反射综合解释

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重症快速反应小组的构建

中华内科杂志 2012年第8期51卷 595-596页

作者： johna.Kellum 张继承 DepartmentofCriticalCareMedicine TheCRISMAClinicalResearchInvestigationandSystemsModelingofAcuteIllnessCenterUniversityofPittsburghPittsburghPA15122USA 山东大学附属省立医院重症医学科

医院里大部分重症或不稳定患者都收在ICU，但大部分意外死亡病例发生在ICU外，也就是普通病房。有研究显示，严重不良事件主要发生在各种原因导致的抢救失败后。Jones等^[1]回顾分析了有关快速反应系统的研究，并评估其效果。结果表明... 详细信息

医院里大部分重症或不稳定患者都收在ICU，但大部分意外死亡病例发生在ICU外，也就是普通病房。有研究显示，严重不良事件主要发生在各种原因导致的抢救失败后。Jones等^[1]回顾分析了有关快速反应系统的研究，并评估其效果。结果表明，亟须提高运用快速反应系统的能力，将患者快速转入ICU，赢得最佳治疗时间，得到最佳治疗。

关键词：快速反应系统重症最佳治疗时间 Jones ICU 死亡病例普通病房不良事件

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进言中国企业:如何攻略美国市场

新经济 2003年第7期 76-78页

作者： johna.Caslione DavidK.Tse 香港大学商学院

我们正看到一种趋势初露端倪.这种趋势将很快成为下个10年里中国商业战略的"主流".更多的有战略头脑的中国公司开始在全世界展开直接的兼并业务,尤其是在美国.

关键词：中国企业兼并美国商业市场文化差异意识形态中小型企业商业全球化

Factors associated with concussion-symptom knowledge and attitudes toward concussion care seeking in a national survey of parents of middle-school children in the US

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Journal of Sport and Health Science 2021年第2期10卷 113-121页

作者： Zachary Y.Kerr Aliza K.Nedimyer Melissa C.Kay Avinash Chandran Paula Gildner K.Hunter Byrd Juliet K.Haarbauer-Krupa johna K.Register-Mihalik Department of Exercise and Sport Science University of North Carolina at Chapel HillChapel HillNC 27599-8700USA Matthew Gfeller Sport-Related Traumatic Brain Injury Research Center University of North CarolinaChapel HillNC 27599-8700USA Injury Prevention Research Center University of North CarolinaChapel HillNC 27510USA Human Movement Science Curriculum University of North CarolinaChapel HillNC 27599-8700USA School of Health Professions University of Southern MississippiHattiesburgMS 39406USA Datalys Center for Sports Injury Research and Prevention IndianapolisIN 46202USA National Center for Injury Prevention and Control Centers for Disease Control and PreventionAtlantaGA 30341USA

Background:Developing appropriate concussion prevention and management paradigms in middle school(MS)settings requires understanding parents’general levels of concussion-related knowledge and *** study examined factors associated with concussion-symptom knowledge and care-seeking attitudes among parents of MS children(aged 10-15 years).Methods:A panel of 1224 randomly selected ***,aged ≥18 years and identifying as parents of MS children,completed an online questionnaire capturing parental and child *** parents’concussion-symptom knowledge was measured using 25 questions,with possible answers being“yes”,“maybe”,and“no”.Correct answers earned 2 points,“maybe”answers earned 1 point,and incorrect answers earned 0 point(range:0-50;higher scores=better knowledge).Concussion care-seeking attitudes were also collected using five 7-point scale items(range:5-35;higher scores=more positive attitudes).Multivariable ordinal logistic regression models identified predictors of higher *** met proportional odds *** odds ratios(aORs)with 95%confidence intervals(95%CIs)(excluding 1.00)were deemed statistically ***:Median scores were 39(interquartile range:32-44)for symptom knowledge and 32(interquartile range:28-35)for care-seeking *** multivariable models,odds of better symptom knowledge were higher in women ***(aOR=2.28;95%CI:1.71-3.05),white/non-Hispanics *** racial or ethnic groups(aOR=1.88;95%CI:1.42-2.49),higher parental age(10-year-increase aOR=1.47;95%CI:1.26-1.71),and greater competitiveness(10%-scale-increase aOR=1.24;95%CI:1.13-1.36).Odds of more positive care-seeking attitudes were higher in white/non-Hispanics *** racial or ethnic groups(aOR=1.45;95%CI:1.06-1.99)and in older parental age(10-year-increase aOR=1.24;95%CI:1.05-1.47).Conclusion:Characteristics of middle school children’s parents(e.g.,sex,race or ethnicity,age)are associated with their concussion-symptom knowle

关键词： Pediatrics Traumatic brain injury Youth

A review of recent research progress on the effect of external influences on tropical cyclone intensity change

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Tropical Cyclone Research and Review 2023年第3期12卷 200-215页

作者： Joshua B.Wadler johna E.Rudzin Benjamin Jaimes de la Cruz Jie Chen Michael Fischer Guanghua Chen Nannan Qin Brian Tang Qingqing Li Embry-Riddle Aeronautical University Department of Applied Aviation SciencesDaytona BeachFLUSA Mississippi State University Department of GeosciencesStarkvilleMSUSA University of Miami Department of Ocean SciencesMiamiFLUSA Princeton University Atmospheric and Oceanic Sciences ProgramPrincetonNJUSA University of Miami Cooperative Institute for Marine and Atmospheric Studies and NOAAAtlantic Oceanographic and Meteorological LaboratoryHurricane Research DivisionMiamiFLUSA Institute of Atmospheric Physics of the Chinese Academy of Sciences BeijingChina Key Laboratory of Transportation Meteorology of China Meteorological Administration Nanjing Joint Institute for Atmospheric SciencesNanjingChina University at Albany State University of New YorkDepartment of Atmospheric and Environmental SciencesAlbanyNYUSA Nanjing University of Information and Science Technology NanjingChina

Over the past four years,signiﬁcant research has advanced our understanding of how external factors inﬂuence tropical cyclone(TC)intensity *** on air-sea interactions shows that increasing the moisture disequilibrium is a very effective way to increase surface heatﬂuxes and that ocean salinity-stratiﬁcation plays a non-negligible part in TC intensity *** wind shear from the environment induces vortex misalignment,which controls the onset of signiﬁcant TC intensiﬁ*** due to upper-level outﬂow from TCs can reduce the magnitude of vertical wind shear,making for TC intensiﬁ*** TC-trough interactions are vital for rapid intensiﬁcation in some TC cases because of strengthened warm air advection,but upper-level troughs are found to limit TC intensiﬁcation in other cases due to dry midlevel air intrusions and increased *** effects on TCs can be divided into direct effects involving aerosol-radiation interactions and indirect effects involving aerosol-cloud *** radiation absorption by the aerosols can change the temperature proﬁle and affect outer rainbands through changes in stability and *** spray and sea salt aerosols are more important in the inner region,where the aerosols increase precipitation and latent heating,promoting more intensiﬁ*** landfalling TCs,the intensity decay is initially more sensitive to surface roughness than soil moisture,and the subsequent decay is mainly due to the rapid reduction in surface moistureﬂ*** new insights further sharpen our understanding of the mechanisms by which external factors inﬂuence TC intensity changes.

关键词： Tropical cyclone External inﬂuence Intensity change Review

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新鲜香菇子实体漆酶的纯化与性质

南京林业大学学报（自然科学版） 1997年第2期21卷 50-53页

作者：叶汉玲王传槐 johna.Buswel 南京林业大学香港中文大学

用硫酸铵分级沉淀，离子交换纤维素柱层析分离技术，对香菇〔Ｌｅｎｔｉｎｕｌａ（Ｌｅｎｔｉｎｕｓ）ｅ－ｄｏｄｅｓ〕子实体漆酶进行分离纯化，得到单一组分的漆酶，通过ＳＤＳ－ＰＡＧＥ凝胶电泳法，测得其摩尔式量为５５０００。研... 详细信息

用硫酸铵分级沉淀，离子交换纤维素柱层析分离技术，对香菇〔Ｌｅｎｔｉｎｕｌａ（Ｌｅｎｔｉｎｕｓ）ｅ－ｄｏｄｅｓ〕子实体漆酶进行分离纯化，得到单一组分的漆酶，通过ＳＤＳ－ＰＡＧＥ凝胶电泳法，测得其摩尔式量为５５０００。研究表明该酶的最适ｐＨ为２．６，最适温度为７０℃，酶的动力学研究测出米氏常数Ｋｍ值为０．１４２ｍｍｏｌ。

关键词：生漆香菇子实体漆酶纯化米氏常数