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DNA SYNTHESIS INHIBITION OF NITROXIDE RADICAlS ON lEUKEMIA CEllS

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Science China Chemistry 1991年第9期34卷 1063-1069页

作者：刘力生郑荣梁 harold M. SWARTZ 张自义魏陆林 Department of Biology Lanzhou University Department of Medicine and Biophysics University of Illinois Department of Chemistry Lanzhou University

4-isothiocyanate-2,2,6,6-tetramethyl-piperidine-l-oxyl has the strongest effects on the DNA synthesis and viability of isolated leukemia 7712 cells. This compound is a very potent inhibitor of DNA synthesis with 50% inhibition of cell DNA synthesis occurring at 2.2 μg/ml, while the lD50 for white mice is 277 mg/kg. During the concentration of 50 μg/ml, the inhibition of DNA synthesis is 99.7%, which is unable to damage the DNA replicate templet. The inhibition of this compound, a combination of nitroxide and isothiocyanate, appears to be stronger than that of the sum of the two separate actions. Much more moderate effects are seen for all the other nitroxide radicals. After reducing nitroxide to hydroxyla-mine, there is no inhibition for DNA synthesis. The free radical mechanism of carcinogene-sis and antitumor action has been discussed.

关键词： nitroxide radical antitumor.

Effect of estrogen on manganese-induced toxicity on embryonic astrocytes

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Advances in Bioscience and Biotechnology 2013年第10期4卷 9-15页

作者： Tyler T. Huynh Kimberly J. Baker harold l. Komiskey Department of Biomedical Sciences Philadelphia College of Osteopathic Medicine-GA Campus Suwanee USA

Manganese (Mn) is a natural trace metal that is essential for many physiological functions in the human body. Astrocytes in the central nervous system are susceptible reservoirs for Mn accumulation. Estrogen, a steroidal hormone, has been shown to mitigate Mn-induced toxicity in cultures of postnatal astrocytes. However, differences in expression/inducibility of glutamate transporters and glutamine synthetase, transmitters, and the natural gonadal steroids and their receptors are known to occur in astrocyte cultures derived from various stages of fetal and postnatal development. Cultures of embryonic (E18) hippocampal astrocytes were examined in this study for the ability of 17 β-estradiol (E2) to protect them from Mn toxicity by up regulating gene expression of a glutamate transporter. Primary rat hippocampal astrocytes were pretreated with β-Estradiol (E2) in vitro and subsequently, Mn sulfate (MnSO4). The amount of toxic damage to the astrocytes was measured by quantifying glial fibrillary acidic protein (GFAP) with a sandwiched Enzyme-linked Immunosorbent Assay (ElISA). ElISA analysis indicated Mn exposure at 100 μM, 300 μM, or 600 μM significantly increased GFAP levels. However, E2 concentrations at 10 nM or 30 nM significantly reduced Mn-induced GFAP concentrations at 100 μM. Cells pretreated with 10 nM or 30 nM of E2 significantly lowered GFAP levels. The Water-Soluble Tetrazolium-8 (WST-8) method was utilized to determine cell viability. The WST-8 assay showed that Mn concentrations of 100 μM, 300 μM, or 600 μM significantly reduced the dehydrogenase activity, thereby decreasing the number of viable astrocytes. Enzyme activity with 600 μM of Mn was significantly decreased when compared with 100 μM of Mn, revealing a dose-dependent effect. However, the dehydrogenase activity in cells treated with 600 μM Mn was significantly increased when pretreated with 10 nM of E2. Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) was used to measure changes in gluta

关键词： Astrocytes Estrogen Embryonic Manganese Hippocampus

Spin-orbit Splitting and lifetime Broadening in the A2△ Electronic State of l-C5H

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Chinese Journal of Chemical Physics 2012年第2期25卷 129-134,I0003页

作者： Mohammad Ali Haddad Dong-feng Zhao harold linnartz Wim Ubachs Institute for lasers Life and Biophotonics VU University Amsterdam De Boelelaan 1081 NL1081HV Amsterdam the Netherlands Sackler laboratory for Astrophysics Leiden Observatory University of Leiden PO Box 9513 NL2300 RA Leiden the Netherlands

Optical absorption bands at -18772 and -18807 cm-1, previously assigned to A2A-X2H electronic origin band transitions of the linear carbon-chain radicals CsH and CsD, respectively, have been reinvestigated. The spectra have been recorded in direct absorption applying cavity ring-down spectroscopy to a supersonically expanding acetylene/helium plasma. The improved spectra allow deducing a l-CsH upper state spin-orbit coupling constant X=-0.7（3） cm-1 and a A2A lifetime of 1.65=0.3 ps.

关键词： Cavity ring down spectroscopy Carbon-chain radical Interstellar molecule CsH

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IDeA：实施机构知识库的思考

图书情报工作动态 2005年第10期 16-20页

作者： Emily Dill kristi l．Palmer 常唯（编译）

近来，机构知识库（Institutional Repositories）已逐渐成为开放获取运动的主角，全世界的图书馆都在积极行动建立自己的机构知识库。但建立一个机构知识库并不仅仅是下载一个软件，然后等待科研人员向其中添加内容那么简单。要成功地... 详细信息

近来，机构知识库（Institutional Repositories）已逐渐成为开放获取运动的主角，全世界的图书馆都在积极行动建立自己的机构知识库。但建立一个机构知识库并不仅仅是下载一个软件，然后等待科研人员向其中添加内容那么简单。要成功地建立一个机构知识库，需要解决许多人力、技术、政策方面的问题。本文总结了印第安纳大学一普度大学的作者和图书馆员在实施IDeA（IUPUI Digital Archive）过程中的经验，目的是对启动IR时需要考虑的问题进行总结概括，以供参考借鉴。

关键词：机构知识库 IDeA 印第安纳大学 Digital 图书馆员科研人员全世界作者开放获取学术交流

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如何实现研发全球化的盈利?

中外管理 2006年第1期 46-48页

作者： Arindam Bhattacharya harold l.Sirkin James P.Andrew 波士顿咨询公司孟买办公室公司芝加哥办公室

跨国公司已纷纷在"快速发展中国家"设立研发部门或研发中心,以推进研发全球化。波士顿咨询公司的研究,有益于中国市场里的各类企业从多侧面认识这一现象。

关键词：研发全球化波士顿咨询公司盈利发展中国家研发中心研发部门跨国公司中国市场企业

What is the role of adolescent body mass index and physical activity on adult health risk behaviors?

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Open Journal of Preventive Medicine 2012年第1期2卷 72-78页

作者： Jennifer A. Pintar kristi l. Storti Vincent C. Arena Robert J. Robertson Elizabeth F. Nagle Andrea M. Kriska Department of Human Performance and Exercise Science Youngstown State University Youngstown USA

Introduction: A high prevalence of modifiable risk factors exists among adolescents that may lead to increased levels of morbidity and mortality in adulthood. This study sought to determine whether higher levels of physical activity (PA) and/or having a healthy body weight in adolescence influences future health risk behaviors (HRB) in young adulthood. Methods: Complete data were gathered for 536 participants from a prospective study and a follow-up survey conducted 10 years apart. At both time points, the questionnaires included information about HRB, PA, and health status. Results: Males who engaged in HRB during adolescence were more likely to continue these same risk behaviors during adulthood. Using multivariate models, only HRB in adolescence predicted HRB in adulthood for drinking, binge drinking and smoking among males, and for binge drinking and smoking among females. Conclusions: It appears that for males, once a health-risk behavior is initiated, it will likely continue into young adulthood, regardless of the presence of other healthy behaviors such as the proper maintenance of body weight and higher levels of PA. Similarly for females, binge drinking and smoking in adolescence is predictive of the same behavior in adulthood.

关键词： Smoking Drinking Binge Drinking

Is rosuvastatin protective against sepsis-associated encephalopathy? A secondary analysis of the SAIlS trial

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World Journal of Emergency Medicine 2022年第5期13卷 367-372页

作者： Shi-yuan Yu Zeng-zheng Ge Jun Xiang Yan-xia Gao Xin lu Joseph harold Walline Mu-bing Qin Hua-dong Zhu Yi li Emergency Department State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalChinese Academy of Medical Science and Peking Union Medical CollegeBeijing 100730China General Medicine Department of Jingnan Medical Center General Hospital of PLABeijing 100039China Emergency Department the First Affi liated Hospital of Zhengzhou UniversityZhengzhou 450052China Department of Emergency Medicine Penn State HealthMilton S.Hershey Medical CenterHershey 17033USA

BACKGROUND:Sepsis is a common cause of death in emergency departments and sepsis-associated encephalopathy(SAE)is a major *** may play a neuroprotective role due to its protective effects on the vascular endothelium and its anti-inflammatory *** study aimed to explore the potential protective function of rosuvastatin against ***:Sepsis patients without any neurological dysfunction on admission were prospectively enrolled in the“Rosuvastatin for Sepsis-Associated Acute Respiratory Distress Syndrome”study(SAIlS trial,*** number:NCT00979121).Patients were divided into rosuvastatin and placebo *** is a secondary analysis of the SAIlS *** characteristics,therapy outcomes,and adverse drug events were compared between ***:A total of 86 patients were eligible for our *** these patients,51 were treated with *** were significantly fewer cases of SAE in the rosuvastatin group than in the placebo group(32.1%vs.57.1%,P=0.028).However,creatine kinase levels were significantly higher in the rosuvastatin group than in the placebo group(233[22-689]U/l vs.79[12-206]U/l,P=0.034).CONClUSION:Rosuvastatin appears to have a protective role against SAE but may result in a higher incidence of adverse events.

关键词： Rosuvastatin calcium Sepsis-associated encephalopathy Anti-infl ammatory agents Sepsis Adverse reactions

Evaluation of Biotinylated PAMAM Dendrimer Toxicity in Models of the Blood Brain Barrier: A Biophysical and Cellular Approach

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Journal of Biomaterials and Nanobiotechnology 2011年第5期2卷 485-493页

作者： Heather A. Bullen Ruth Hemmer Anthony Haskamp Chevelle Cason Stephen Wall Robert Spaulding Brett Rossow Michael Hester Megan Caroway kristi l. Haik 不详

The interaction of biotinylated G4 poly(amidoamine) (PAMAM) dendrimer conjugates and G4 PAMAM dendrimers with in vitro models of the blood brain barrier (BBB) was evaluated using langmuir Blodgett monolayer techniques, atomic force microscopy (AFM) and lactate dehydrogenase measures of cell membrane toxicity. Results indicate that both G4 and G4 biotinylated PAMAM dendrimers disrupt the composition of the liquid condensed (lC) and liquid expanded (lE) phases of the 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) lipid monolayer. The disruption is concentration dependent and more marked for G4 biotinylated PAMAMs. lactate dehydrogenase (lDH) assays using endothelial cell culture models of the BBB indicate that biotinylation results in higher levels of toxicity than non-biotinylation. This approach provides valuable information to assess nanoparticle toxicity for drug delivery to the brain.

关键词： Dendrimers Drug Delivery Blood Brain Barrier Toxicity

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成本可以减客服不能降

商学院 2010年第4期 73-75页

作者： harold l．Sirkin 波士顿咨询公司

风雨飘摇的日航虽然由日本管理四圣之一稻盛和夫接管，不确定性依然不小。稻盛著名的“阿米巴经营”模式是否会帮助日航走出困境？面对经济衰退的冲击，许多公司都下调收入预测。勒紧腰带，但过度削减成本，损害了企业最有价值的资产：... 详细信息

风雨飘摇的日航虽然由日本管理四圣之一稻盛和夫接管，不确定性依然不小。稻盛著名的“阿米巴经营”模式是否会帮助日航走出困境？面对经济衰退的冲击，许多公司都下调收入预测。勒紧腰带，但过度削减成本，损害了企业最有价值的资产：与最佳客户的关系。联合航空和安飞士的例子说明，关键的客户关系必须小心呵护。艰难时期终究会过去，如果企业的最佳客户在衰退时期转换门庭，那么企业可能再也难以赢回他们的芳心。

关键词：削减成本稻盛和夫最佳客户不确定性经济衰退收入预测客户关系企业