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Impact of poly chlorinated biphenyl (Aroclor 1254) and vitamin C on antioxidant system of rat ventral prostate

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Asian Journal of Andrology 2004年第1期6卷 19-22页

作者： m. Sridhar P. Venkataraman S. Dhanammal A. Arunkumar m.m. Aruldhas N. Srinivasan J. Arunakaran Department of Endocrinology Dr. ALM Post Graduate Institute of Basic Medical Sciences University of MadrasTaramani Chennai 600 113 India

Aim: To evaluate the effect of polychlorinated biphenyls (PCB) and vitamin C on ventral prostatic antioxidant system in adult male rats. methods: A group of 20 adult male rats were administered ip Aroclor 1254 in corn oil at a dose of 2 mg·kg-1·day-1 for 30 days. Ten control rats were administered only the vehicle. After 30 days the treated rats were divided at random into 2 sub-groups of 10 animals each. One sub-group received vitamin C at a dose of 500 mg·kg-1·day-1 for 10 days. The other group was maintained as Aroclor 1254 control. Twenty-four hours after the last treatment the rats were killed by decapitation. Ventral prostatic homogenate was prepared and used for the estimation of enzymatic antioxidants, including superoxide dismutase (SOD), catalase (CAT) and glutathione-S-transferase (GST) and hydrogen peroxide (H2O2), lipid peroxidation (LPO) and prostatic acid phosphatase. The serum levels of total T3, total T4, TSH, testosterone and estradiol were also assayed. Results: The body weight and ventral prostatic weight were reduced in PCB treated rats. The activities of SOD, CAT, GST and acid phosphatase were decreased while the levels of H2O2 and lipid peroxidation were increased in the ventral prostate of PCB treated rats. Administration of vitamin C restored these parameters. Serum levels of thyroid hormones, estradiol and testosterone were decreased in PCB treated animals. Administration of vitamin C restored the thyroid hormone levels. Conclusion: PCB induces oxidative stress and decreases the antioxidant enzymes in the ventral prostate of adult male rats; the effects could be reversed by the administration of vitamin C.

关键词： polychlorinated biphenyls Aroclor 1254 ventral prostate antioxidants lipid peroxidation thyroid hormone vitamin C

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儿童期早期哮喘症状与预后

世界核心医学期刊文摘（儿科学分册） 2006年第A10期2卷 9-10页

作者： Goksfr E. U■ark m. alm.B. G. Wennergren 李开 Department of Paediatrics Gteborg University Queen Silvia Children' s Hospital SE- 416 85 Gteborg Sweden

Aim: To study the outcome in early adulthood for children with early asthma symptoms and to analyse the factors associated with current asthma. methods: In a prospective study, we have re- investigated 89/101 children who were hospitalized before the age of two years due to wheezing. The children were investigated using a questionnaire and allergy and bronchial hyperresponsiveness tests at the age of 17- 20 years and compared with age- matched controls. Results: In the cohort, 43% had had asthma symptoms in the preceding 12 months compared with 15% in the control group. The strongest risk factors for asthma were current allergy, bronchial hyper- responsiveness and female gender. Female gender and passive smoking in infancy were independent infantile risk factors. In addition to female gender, two pathways led to current asthma: an allergic pathway from family atopy via the development of allergy and another pathway from early passive smoking via hyperresponsiveness and active smoking. Conclusion: In children with early wheezing disorder, current allergy, bronchial hyper- responsiveness and female gender were the strongest risk factors for asthma in early adulthood, while female gender and passive smoking in infancy were independent infantile risk factors. The effects of early passive smoking persist longer than previously reported.

关键词：哮喘症状童期支气管高反应性被动吸烟过敏体质婴儿期早发性家族遗传性女性性别

Band structure,Fermi surface,elastic,thermodynamic,and optical properties of AlZr3,AlCu3,and AlCu2Zr:First-principles study

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Chinese Physics B 2016年第8期25卷 103-112页

作者： Parvin R Parvin F Ali m S Islam A K m A Department of Physics Rajshahi University Rajshahi-6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong 154/A College Road Chittagong-4203 Bangladesh

The electronic properties（Fermi surface,band structure,and density of states（DOS）） of Al-based alloys alm.（m=Zr and Cu） and AlCu2Zr are investigated using the first-principles pseudopotential plane wave method within the generalized gradient approximation（GGA）.The structural parameters and elastic constants are evaluated and compared with other available ***,the pressure dependences of mechanical properties of the compounds are *** temperature dependence of adiabatic bulk modulus,Debye temperature,specific heat,thermal expansion coefficient,entropy,and internal energy are all obtained for the first time through quasi-harmonic Debye model with phononic effects for T = 0 K-100 *** parameters of optical properties（dielectric functions,refractive index,extinction coefficient,absorption spectrum,conductivity,energy-loss spectrum,and reflectivity） of the compounds are calculated and discussed for the first *** reflectivities of the materials are quite high in the IR-visible-UV region up to ~ 15 eV,showing that they promise to be good coating materials to avoid solar *** of the properties are also compared with those of the Al-based Ni3 Al compound.

关键词： first principle calculations Fermi surface elastic moduli entropy and internal energy optical properties

Shannon information entropies for rectangular multiple quantum well systems with constant total lengths

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Chinese Physics B 2018年第4期27卷 154-163页

作者： m Solaimani Guo-Hua Sun Shi-Hai Dong Department of Physics Faculty of Science Qom University of Technology Qom Iran Catedrática CONACyT CIC lnstituto Politécnico Nacional Unidad Profesional ALM CDMX C. P. 07700 Mexico Laboratorio de Informacién Cuántica CIDETEC Instituto Politécnico Nacional Unidad Profesional ALM CDMX C. P. 07700 Mexico

We first study the Shannon information entropies of constant total length multiple quantum well systems and then explore the effects of the number of wells and confining potential depth on position and momentum information entropy density as well as the corresponding Shannon *** find that for small full width at half maximum（FWHm） of the position entropy density,the FWHm of the momentum entropy density is large and vice *** increasing the confined potential depth,the FWHm of the position entropy density decreases while the FWHm of the momentum entropy density *** increasing the potential depth,the frequency of the position entropy density oscillation within the quantum barrier decreases while that of the position entropy density oscillation within the quantum well *** increasing the number of wells,the frequency of the position entropy density oscillation decreases inside the barriers while it increases inside the quantum *** an example,we might localize the ground state as well as the position entropy densities of the1 st,2 nd,and 6 th excited states for a four-well quantum ***,we verify the Bialynicki–Birula–mycieslki（BBm）inequality.

关键词： position and momentum Shannon entropies multiple quantum well entropy densities

Origin and Petrogenetic Implications of Spessartine Garnet in Highly-Fractionated Granite from the Central Eastern Desert of Egypt

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Acta Geologica Sinica(English Edition) 2020年第3期94卷 763-776页

作者： mabrouk SAmI Theodoros NTAFLOS Haroun A.mOHAmED Esam S.FARAHAT Christoph HAUZENBERGER Nasser m.mAHDY Khaled m.ABDELFADIL Douaa FATHY Geology Department Faculty of ScienceMinia UniversityEl-Minia 61519Egypt Department of Lithospheric Research University of ViennaAlthanstrasse 14A-1090 ViennaAustria Institute of mineralogy and Petrology Karl-Franzens UniversityGrazAustria Nuclear materials Authority P.O.530El-MaadiCairoEgypt Geology Department Faculty of ScienceSohag UniversityEgypt

A highly-fractionated garnet-bearing muscovite granite represents the marginal granitic facies of the Abu-Diab multiphase pluton in the Central Eastern Desert of Egypt. New electron microprobe analyses(EmPA) and laser ablation inductively coupled plasma mass spectrometry(LA-ICP-mS) data from garnets are reported, in order to constrain their origin and genesis. Garnet in the Abu-Diab host granite is euhedral to subhedral, generally homogeneous and, in rare cases, it shows weak zonation. The garnet contains appreciable amounts of mnO and FeO, with lesser amounts of mgO and CaO, yielding an end-member formula of Sps61–72alm.5–35Prp1–4Adr0–1. moreover, it is depleted in large ion lithophile elements(LILE) with lower values of Ba, Nb and Sr relative to the primitive mantle. Additionally, it contains high concentrations of HREE and Y and their REE pattern shows strong negative Eu anomalies. The garnet was crystallized under relatively low temperature(646°C–591°C) and pressure(mical features indicate that the garnet is magmatic in origin and is chemically similar to that from highly-fractionated A-type granite. It was probably formed at the expense of biotite in a highly-evolved mnO-rich magma and/or by hydroxyl complexing of mn during the ascending fluid phases.

关键词： spessartine garnet LA-ICP-mS A-type granite Abu-Diab Egypt

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北方沼泽地水位下降对全球气候变暖的影响

人类环境杂志 1996年第3期25卷 179-184页

作者： Jukka Laine Jouko Silvola Kimmo Tolonen Jukka alm.Hannu Nyknen Harri Vasander Tapani Sallantaus Ilkka Savolainen Jukka Sinisalo Pertti J.m.rtikainen 钱云 Department of Forest Ecology P.O.Box24

自从最后一次冰川消退以来,北方沼泽地(3.46亿hm^2)积存了300～500Pg碳。这些沼泽地在分离二氧化碳(CO_2)的同时,释放了相当数量的甲烷(CH_4)到大气中。正如对高纬地区预报的那样,如果夏季变得更热、更干,未来沼泽地温室气体的平衡将发... 详细信息

自从最后一次冰川消退以来,北方沼泽地(3.46亿hm^2)积存了300～500Pg碳。这些沼泽地在分离二氧化碳(CO_2)的同时,释放了相当数量的甲烷(CH_4)到大气中。正如对高纬地区预报的那样,如果夏季变得更热、更干,未来沼泽地温室气体的平衡将发生变化,随之而来的CH_4排放将减少,而CO_2和N_2O的排放将增加。北部沼泽地水位下降预计将增强温室效应的影响。我们分别在不同营养水平的未排水和排水的沼泽地测量了碳循环的组分,并把这些结果归纳成一个简单的辐射强迫因子,用以评价水位下降对大气的综合影响。在对存于土壤和树木中的碳以及为经营森林而排水引起的水位下降后CO_2、CH_4和N_2O的通量的变化作出测量的基础上,我们提出一个假设,即由气候变化引发的干旱趋势将减弱北方沼泽地对总辐射强迫的影响,这一影响在100年内约为0.1W/m^2。CH_4排放的减少,沼泽地碳储量的微小变化和树木生物量储存的增加都将导致这一变化。

关键词：中国北方沼泽地水位下降气候变暖

Petrology of Garnet Amphibolites from the Hualong Group: Implications for metamorphic Evolution of the Qilian Orogen, NW China

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Journal of Earth Science 2018年第5期29卷 1102-1115页

作者： Yilong Li Limin Zhao Zhuoyang Li Biji Luo Jianping Zheng Fraukje m.Brouwer School of Earth Sciences State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Geology & Geochemistry Group Department of Earth Sciences VU Amsterdam

The Qilian Orogen marks the junction of the North China, South China and Tarim cratons. The mechanism of continental growth during the formation of the orogen remains unclear. Based on detailed fieldwork, we present a systematic study of petrography, mineral chemistry and phase equilibria of garnet amphibolites from the Hualong Group, which represents the Precambrian basement in the southern accretionary belt of the Qilian Orogen. The garnet amphibolites mainly consist of amphibole, plagioclase, garnet and quartz, with minor pyroxene, biotite and ilmenite. A peak stage of upper amphibolite facies to low-temperature granulite facies metamorphism and retrograde metamorphism in the amphibolite facies affected the samples. Garnet has a homogeneous composition of alm.6-71Grs14-17Prp9_12Sps3-s, amphibole is ferro-hornblende, biotite belongs to the ferro-biotite species and pyroxene is dominated by orthopyroxene with few clinopyroxene. Pseudosection modeling of the garnet amphibolite samples indicates clockwise P-T paths. The samples witness peak metamorphism at conditions of -4.9-6.3 kbar and -755-820 ℃ in the upper amphibolite facies to low- temperature granulite facies, and retrograde cooling and decompression at conditions of-2.5-3.1 kbar and -325-545 ℃. It is inferred that peak metamorphism with high temperature and low pressure occurred at ca. 450 ma during northward subduction of the South Qilian oceanic crust beneath the central Qilian Block. When continental collision occurred between the central Qilian and the Qaidam blocks, the Hualong Block was aecreted onto the South Qilian accretionary complex and experienced amphibolite facies retrograde metamorphism at ca. 440 ma.

关键词： Qilian Orogen Hualong Group garnet amphibolite petrology metamorphic P-T path PerpleX.

肾源性系统性纤维化与钆对比剂:欧洲泌尿生殖放射学会最新对比剂安全指南

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国际医学放射学杂志 2013年第2期 193-193页

作者： H.S. Thomsen S.K. morcos T. alm.n m.F. Bellin m. Bertolotto G. Bongartz 李宁 Department of Diagnostic Radiology 54E2 Copenhagen University Hospital Herlev Herlev Ringvej 75 2730 Herlev Denmark

目的更新欧洲泌尿生殖放射协会(ESUR)的对比剂安全委员会(CmSC)关于肾源性系统性纤维化(NSF)及钆对比剂的指导方针。涉及内容审查内容包括病史、临床表现及肾源性系统性纤维化的发病率和目前对其病理生理学的了解。讨论引起NSF的风险因... 详细信息

目的更新欧洲泌尿生殖放射协会(ESUR)的对比剂安全委员会(CmSC)关于肾源性系统性纤维化(NSF)及钆对比剂的指导方针。涉及内容审查内容包括病史、临床表现及肾源性系统性纤维化的发病率和目前对其病理生理学的了解。讨论引起NSF的风险因素并推荐预防措施。对不同钆对比剂的稳定性和钆对人体潜在的长期影响也进行了研究。要点①回顾肾NSF的临床特征、危险因素及预防措施。②病人肾小球滤过率低于30mL/(min·1.73m2)时可增加NSF发生的危险性。③低稳定性钆对比剂与NSF的发生具有显著相关性。④遵循钆对比剂指导方针最大程度地降低了NSF的风险。⑤讨论了钆在人体蓄积潜在的长期危害。

关键词：肾源性系统性纤维化对比剂钆肾功能不全

在CTA与血管造影中使用与诊断性钆剂量等密度的超低碘对比剂剂量,该法是否可使氮质血症病人避免CIN与NSF?

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国际医学放射学杂志 2011年第2期 200-200页

作者： U.Nyman B.Elmsthl H.Geijer P.Leander T.alm.n m.Nilsson 唐光健 Department of Diagnostic Radiology Lasarettet TrelleborgUniversity of Lund

目的确立氮质血症病人诊断性CTA与经皮导管血管造影/血管内介入(PCA/PVI)时与钆(Gd)对比剂(Cm)等密度的碘(I)Cm剂量。材料与方法含有0.01、0.02、0.05、

关键词：血管造影对比剂肾衰竭肾性系统性纤维化体层摄影术 X线计算机