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Lead isotopic study of Shang Dynasty bronzes (13-11 B.C.)and their ore sources

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Nuclear science and Techniques 2000年第2期11卷 65-71页

作者： PENG Zi-Cheng ZHANG Zhao-Feng HE Jian-Feng WANG Zhao-Rong(Department of Earth and Space science, Univcrsity of Sciencc and Technology of China,Hefei 230026)LIU Shi-Zhong(jiangxi Historical Relic Archaeology Rescarch institute, nanchang 330003)HUA Jue-Mi Department of Earth and Space science University of Science and Technology of ChinaHefei 230026 jiangxi Historical Relic Archaeology Research institute Nanchang 330003 Natural science Historical institute the Chinese Academy of Sciences Beijing 100010

The Shang Dynasty civilization in China is based on the development of the bronze techniques. A large amount of Shang Dynasty bronzes, excavated from jiangxi, Hubei and Henan provinces, have become a focus of world attention. However,the Sha-ng Dynasty center was located at Zhenzhou and Allyang city areas, Henan province, where no large copper ores have been found so far. Therefore, where did the huge ore material for casting the bronzes come from? It is an unsettled question paid attention by the archaeologists and scicntists. 35 Shang Dynasty bronzes and 21 copper and lead ore materials aged in the Shang-Zhou Dynasty, the Spring-Autumn Period and the modern time, have been measured by the use of mass *** upon lead isotopic ratios, the ore material for casting the bronzes with the middle isotopic ratios of 207Pb/206Pb ranged in 0.8～0.9 could come from the ancient copper mine of Tongling, jiangxi province and Tong Lushan, Hubei province and that with the high isotopic ratios (＞0.9) could be from the northern part of the Shang Empire, called "Gongfang" in the historical records, e.g. today’s Hebei and Liaoningprovinces. The others with the low isotopic ratios (＜0.8) might originate from poly-metalic deposits, with the high isotopic ratios of 238U/204 Pb in the ore flux or in the magma.

关键词：商代青铜器铜铜矿石材料同位素比率考古商代文明来源

Ca^(2+) signals induced from calcium stores in pancreatic islet β cells

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Chinese science Bulletin 2000年第1期45卷 51-56页

作者： zeng xuhui, QU Anlian, LOU Xuelin, XU Jianhua, WANG Junjian, WU Hongxiu & ZHOU Zhuan1. institute of Biochemistry and Biophysics, Huazhong university of science and Technology, Wuhan 430074, China 2. Pharmacology, Huazhong university of science and Technology, Wuhan 430074, China 3. School of life sciences, university of science and Technology of China, Hefei 230027, China Correspondence should be addressed to Zhou Zhuan. institute of Biochemistry and Biophysics Huazhong University of Science and Technology Wuhan China Pharmacology Huazhong University of Science and Technology Wuhan China School of life sciences University of Science and Technology of China Hefei China

In single rat pancreatic βcells, using fura-2 microfluorometry to measure [Ca2+] response upon different stimuli, the ways of calcium regulation have been studied. When the extracellular calcium concentration was 2.5 mmol/L, either 60 mmol/L KCI, 20 mmol/L D-glucose or 0.1 mmol/L tolbutamide induced increase in [Ca2+]. Such increase in [Ca2+] was absent when the same stimuli were applied under zero extracellular calcium. These results indicate that the increase of [Ca2+] is induced by the activation of voltage-dependent calcium channels in p celis. The manifold forms of [Ca2+] change induced by glucose imply that the effects of glucose are complex. 5 mmol/L caffeine or 5 mmol/L MCh increase the [Ca2+], which is independent of the external calcium, suggesting that [Ca2+] can be regulated by Ca2+ release from not only the IP3-sensitive but also the ryanodine sensitive calcium stores in p celis. The latency of Ca responses for IP3 pathway (5 s) is faster than that for ryanodine pathway (30 s), it is

关键词： pancreatic β cell [Ca2+]i calcium stores glucose fura-2.

Synthesis of Monodisperse Poly(chloromethylstyrene divinylbenzene)Particle and Its Applications

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Chinese Chemical Letters 1998年第11期9卷 0-0,0-0页

作者： Yin Mao WEI Xin Du GENG (institute of Modern Separation science, Key Laboratory of Modern Separation science in Shaanxi province, Northwest university, Xi’an 710069) NW Univ Xian Inst Modern Separat Sci Key Lab Modern Separat Sci Shaanxi Prov Xian 710069 Peoples R China

Monodisperse poly (chloromethylstyrene divinylbenzene) particles were prepared by a two-step swelling method. It was demonstrated that the packings have comparative advantages for biopolymer separation with high column efficiency, low interstitial volume and low back pressure to the packings prepared with suspension polymerization method. Using size exclusionchromatography and weak ion exchange chromatography as examples, it was shown that these packings could be modified chemically more easily than poly (styrene divinylbenzene) packings.

关键词： Monodisperse poly (chloromethylstyrene divinylbenzene) particles synthesis size exclusion chromatography weak cation exchange chromatography rotein separation

Molecular identification of the cytoplasmic male sterile source from Dongxiang wild rice(Oryza rufipogon Griff.)

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Journal of Integrative Agriculture 2017年第8期16卷 1669-1675页

作者： YAN Song ZHU Shan MAO Ling-hua HUANG Ren-liang XIONG Hong-liang SHEN Lin-jun SHEN Xian-hua Rice National Engineering Laboratory(nanchang)/nanchang Sub-center National Rice Improvement Center/Jiangxi Provincial Key Laboratory of Rice Physiology and Genetics/Rice Research InstituteJiangxi Academy of Agricultural Sciences Key Laboratory of Crop Physiology Ecology and Genetic BreedingMinistry of Education/College of AgronomyJiangxi Agricultural University jiangxi Super-rice Research and Development Center Jiangxi Academy of Agricultural Sciences

The use of cytoplasm male sterility （CMS） is crucial for three-line hybrid seed production. Two types of CMS have been discovered from Dongxiang wild rice, namely the wild abortion type CMS （CMS-WA） and the Dongxiang wild type CMS （CMS-DW）. In this study, we show the molecular identification of the two types of CMS in Dongxiang wild rice. WA352, which conferred CMS-WA, was not detected in Dongxiang wild iice, implying Dongxiang wild rice does not carry the CMS- WA source. Further analysis of WA352 in DYIA, a CMS-DW line, by PCR amplification and sequencing, revealed two insertion-deletion polymorphisms occurred in CMS-DW compared to WA352 of CMS-WA. It was reported that WA352 was comprised of an unknown origin sequence and partial sequences of three open reading frames （ORFs）, orf284, orf224 and orf288. The 42-bp insertion was located between the two segments of orf224 and orf288, which created a new chimeric ORF, orf216. This new ORF was also detected in CMS-HL. Based on the 9-bp deletion in orf284, a specific mitochon- drial marker of DW-M1 was developed, which could be used to specifically distinguish the DW-type source. Moreover, semi-quantitative RT-PCR analysis preliminarily suggested that both orf216 and orf284 could be considered as candidates for CMS-DW. These findings present a preliminary understanding of CMS-DW at the molecular level.

关键词： Dongxiang wild rice cytoplasm male sterile WA352 orf216 orf284 mitochondrial marker

Observation on the initial inoculum source and dissemination of Entomophthorales-caused epizootics in populations of cereal aphids

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science China(life sciences) 2004年第1期47卷 38-43页

作者： CHEN Chun & FENG Mingguanginstitute of Microbiology, College of life science, Zhejiang university, Hangzhou 310029, China institute of Applied Entomology, College of Agricultural sciences and Biotechnology, Zhejiang university, Hangzhou 310029, China 1. institute of Microbiology College of Life Science Zhejiang University 310029 Hangzhou China 2. institute of Applied Entomology College of Agricultural Sciences and Biotechnology Zhejiang University 310029 Hangzhou China

A total number of 1092 migratory alates were trapped from air in wheat grown area of Yuanyang County, Henan province from early April through May 2002 in order to confirm the source and dissemination of entomophthoralean inocula to cause epizootics of cereal aphids. Those included 415 Sitobion avenae, 642 Rhopalosiphum padi, 22 Metopolophium dirhodum, and 13 Schizaphis graminum. The trapped alates were daily collected and individually reared for 7 days on wheat plants in laboratory. Of those 341 alates died of fungal infection, taking 31.2% in the trapped alates. These included 224 S. avenae, 106 R. padi, 8 M. dirhodum, and 3 S. graminum. Deaths of all infected alates occurred during the first 5 days and 78.9% of the deaths occurred within the first 3 days. Individual examination under microscope proved that all deaths were attributed to entomophthoralean fungi. Of those Pandora neoaphidis accounted for 84.6%, Conidiobolus obscurus for 9.9%, and Entomophthora planchoniana for 5.5%. Four alate deaths died of cross infection of P. neoaphidis and C. conidiobolus. Based on the high infection rate of the migratory alates trapped from air and the field occurrence of epizootics in populations of cereal aphids during the trapping period, Entomophthorales-caused epizootics were likely disseminated by infected alates through their flight and colonization. This makes it reasonable to interpret worldwide distribution of aphid epizootics, particularly caused by P. neoaphidis that has no resting spores discovered.

关键词： Entomophthorales, cereal aphids, infected alates, initial inoculum, fungal dissemination.

Integrin β4 mAb inhibited apoptosis induced by deprivation of growth factors in vascular endothelial cells

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Acta Pharmacologica Sinica 2004年第6期25卷 31-35页

作者： Ke-wen ZHAO, Qi-tao ZHAO, Shang-li ZHANG, Jun-ying MIAO2 institute of Developmental Biology, School of life science, Shandong university, Ji-nan 250100, China institute of Developmental Biology School of Life Science Shandong University Ji-nan 250100 Chin

AIM: To understand the mechanism by which anti-β4 integrin monoclonal antibody (mAb) inhibits apoptosis of vascular endothelial cells (VEC). METHODS: Viability was determined by counting the cells that attached to dishes after treatments. DNA fragmentation was analyzed by agarose gel electrophoresis and fluorescence microscopy. The intracellular content of cAMP was measured by radioimmunoassay (RIA). The levels of p53 and Ras expres- sions were analyzed by fluorescence microscopy combined with immunofluorescence under laser scanning confo- cal microscopy. RESULTS: After the cells were deprived of fibroblast growth factor (FGF) and serum were exposed to the mAb 5 mg/L for 24 h, the detachment and DNA fragmentation of these cells were suppressed. When cells were deprived of FGF and serum, the intracellular cAMP level and Ras protein content decreased (P<0.05), while the level of p53 protein expression increased (P<0.05). But in the presence of anti-β4 integrin mAb, VEC apoptosis was inhibited, and at the same time, the changes mentioned above were obviously blocked (P<0.05). CONCLUSION: Anti-4 integrin mAb inhibited apoptosis by affecting the level of cAMP, and blocking down- regulation of Ras protein and up-regulation of p53 protein in VEC.

关键词： integrin 4 monoclonal antibodies apoptosis umbilical veins vascular endothelium cyclic AMP protein p53 ras genes

ON THE GROWTH OF SOLUTIONS TO HIGHER ORDER DIFFERENTIAL EQUATION

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Annals of Differential Equations 2012年第2期28卷 170-179页

作者： Juan Gong, Zongxuan Chen (School of Mathematical sciences, South China Normal university, Guangzhou 510631) Xiumin Zheng (institute of Math. and Information science, jiangxi Normal university, nanchang 330022)

In this paper, we consider a higher order differential equation and obtain a precise estimate of the order of growth and the hyper-order of solutions to the equation.

关键词： differential equation entire function order of growth hyper-order

New fossil ommatid (Coleoptera:Archostemata:Ommatidae) from Jehol Biota of western Liaoning, China

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Progress in Natural science:Materials International 2006年第6期16卷 639-643页

作者： REN Dong, TAN Jingjing and GE Siqin (College of life science, Capital Normal university, Beijing 100037, China institute of Zoology, Chinese Academy of sciences, Beijing 100080, China) [a]College of life science Capital Normal University Beijing China [b]institute of Zoology Chinese Academy of Sciences Beijing China

In this paper one new genus and one new species of fossil ommatid, Odontomma trachylaena gen. et sp. nov., is described and illustrated from the Late Jurassic or Early Cretaceous Yixian Formation of western Liaoning, China. Based on wide epipleural space of elytron with several rows of cells, the new taxa is attributed to tribe Brochocoleini of Ommatidae and compared with genus Bro-chocoleus. Due to the fact that most other Chinese Mesozoic ommatids are not complete, the complete preservation of the new specimens reported here enabled us to determine the characteristics of the body of these ancient ommatid. Moreover, based on the well-preserved individual of this new genus, we may suppose the affinities of the new species with extant and extinct groups.

关键词： Ommatidae Late Jurassic Early Cretaceous Liaoning province.

Synthesis of 2,6-Dimethoxyhydroquinone-3-mercaptoacetyl-peptide-chlorambucil Conjugates

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Chinese Chemical Letters 2000年第10期11卷 879-882页

作者： Yu Fei SONG (institute of Molecular science, Shanxi university, Taiyuan 030006) Shanxi Univ Inst Mol Sci Taiyuan 030006 Peoples R China

This paper reports a continous study of the use of short chain peptides as carriers of a potential antitumor agents: 2,6-dimethoxyhydroquinone-3-mercaptoacetic acid (DMQ-MA). In an effort to carry out anti-cancer drug design, we synthesized another two new DMQ-MA-peptide-chlorambucil (CRB) derivatives: DMQ-MA-Lys(CRB)-Arg-OMe, DMQ-MA-Lys(DMQ-MA)Lys(CRB)-Arg-OMe. These peptide-chlorambucil conjugates were synthesized by coupling protected amino acids in solution and the next conjugation was achieved by reacting with pentafluorophenyl ester of DMQ-MA in DMF. The CRB in side chain was coupled by deblocking the lysyl-carbobenzyloxy protecting group Z and then reacting with the pentafluorophenyl ester of chlorambucil (CRB). Further study on cytotoxicity, DNA binding, and sequence specificity of DNA alkylation of these two new conjugates are investigating.

关键词： 2.6-dimethoxyhydroquinone-3-mercaptoacetic acid chlorambucil peptide