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Chinese Science Bulletin 1999年第20期44卷 1851-1858页

作者： Shi, YF liu, xd Li, BY Yao, TD Chinese Acad Sci Lanzhou Inst Glaciol & Geocryol Lanzhou 730000 Peoples R China Chinese Acad Sci Lanzhou Inst Plateau Atmospher Phys Lanzhou 730000 Peoples R China Chinese Acad Sci Inst Geog Beijing 100101 Peoples R China

Guliya ice core records, high lake-level records in the Qinghai-Xizang Plateau and at its north side as well as vegetation succession records indicated that during the period of 30-40 kaBP, namely the later age of the megainterstadial of last glacial period, or the marine oxygen isotope stage 3, the climate of the Qinghai-Xizang Plateau was exceptionally warm and humid, the temperature was 2-4℃ higher than today and the precipitation was 40% to over 100%

关键词： Qinghai-Xizang (Tibet) Plateau very strong summer monsoon precessional cycle 30-40 kaBP.

2个Ⅰ型Waardenburg综合征家系的基因诊断及产前诊断

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中华耳鼻咽喉头颈外科杂志 2016年第12期51卷 896-901页

作者：白莹刘宁孔祥东闫洁秦兆冰王斌郑州大学第一附属医院遗传与产前诊断中心郑州450052 郑州大学第一附属医院耳科郑州450052

目的分析2个中国汉族Ⅰ型Waardenburg综合征（WS1）家系致病基因PAX3的突变位点,并在此基础上探讨PAX3基因分析用于产前诊断的可行性.方法 2015年7月和2016年3月分别有2例汉族家族遗传性WS1患者在郑州大学第一附属医院就诊,采集2个家系... 详细信息

目的分析2个中国汉族Ⅰ型Waardenburg综合征（WS1）家系致病基因PAX3的突变位点,并在此基础上探讨PAX3基因分析用于产前诊断的可行性.方法 2015年7月和2016年3月分别有2例汉族家族遗传性WS1患者在郑州大学第一附属医院就诊,采集2个家系（WS1-01和WS1-02）成员血样并留取临床资料.应用多聚酶链反应（PCR）结合sanger测序和多重连接探针扩增技术（multiplex ligation-dependent probe amplification,MLPA）对2个WS1家系中2例先证PAX3基因进行检测,获得变异序列后,针对所检出变异序列对家系成员和健康对照个体的PAX3基因序列进行变异验证分析;确定致病性突变后,对WS1-01家系中的高危胎儿进行孕中期产前诊断.结果在WS1-01家系的患者中均检测出了PAX3基因第7外显子杂合缺失,家系中表型正常者和20名健康对照者均未检测到此突变;高危胎儿未检测出与患者相同的致病突变,出生后表型正常.在WS1-02家系的2例患者中均检测到AX3基因第8外显子c.1385_1386delCT微小缺失突变（可导致移码框的改变）,家系中表型正常者和200名健康对照者均未检测到此突变.结论 PAX3基因第7外显子缺失突变和第8外显子c.1385_1386delCT是本研究2个WS1家系的致病原因,测序分析结合MLPA技术可对该2个WS1家系进行有效的基因诊断和产前诊断.

关键词： Waardenburg综合征听觉丧失,感音神经性 PAX3转录因子突变产前诊断

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生物黏附材料壳聚糖的黏附性能

中国组织工程研究与临床康复 2007年第26期11卷 5140-5143页

作者：王媛珍郑建华包德才林军章孙志杰刘袖洞马小军中国科学院大连化学物理研究所生物医用材料工程组渤海大学化学与化工学院辽宁省锦州市121000

目的:考察壳聚糖与黏蛋白的相互作用,评价壳聚糖黏附性能的影响因素。方法:于2006-07/12在中国科学院大连化学物理研究所生物医用材料工程实验室完成。将壳聚糖溶液与黏蛋白溶液混合,用紫外分光光度计测定溶液混合前后紫外吸收值的变化... 详细信息

目的:考察壳聚糖与黏蛋白的相互作用,评价壳聚糖黏附性能的影响因素。方法:于2006-07/12在中国科学院大连化学物理研究所生物医用材料工程实验室完成。将壳聚糖溶液与黏蛋白溶液混合,用紫外分光光度计测定溶液混合前后紫外吸收值的变化,表征壳聚糖的黏附性能。①调节反应溶液的pH值(1.0,3.0,5.0),考察环境pH对壳聚糖黏附性能的影响。②改变反应温度(4,25,37℃),考察环境温度对壳聚糖黏附性能的影响。③选择不同相对分子质量(48000,124000,230000)的壳聚糖,考察壳聚糖相对分子质量对其黏附性能的影响。④选择不同脱乙酰度(56%,67%,97%)的壳聚糖,考察壳聚糖脱乙酰度对其黏附性能的影响。⑤使用不同种类(I-S型及Ⅲ型)黏蛋白,考察黏蛋白中唾液酸含量对壳聚糖黏附性能的影响。结果:①环境介质pH由1.2升至5.0时,壳聚糖黏附性能随之显著升高。②壳聚糖黏附性能随着温度的升高而显著增强。③壳聚糖相对分子质量对于壳聚糖黏附无显著影响。④壳聚糖脱乙酰度增加,其黏附性能显著增强。⑤I-S型黏蛋白与壳聚糖的作用较之Ⅲ型黏蛋白与壳聚糖的相互作用明显增强。结论:壳聚糖的黏附受环境pH、温度、壳聚糖及黏蛋白两种分子电荷密度的显著影响;在酸性环境下增大环境pH值、升高环境温度、增加壳聚糖的脱乙酰度和增加黏蛋白中唾液酸的含量,均有利于壳聚糖的黏附。

关键词：壳聚糖生物黏附黏附性能黏附机制黏蛋白生物材料

Application of carbazole compounds in study of hydrocarbon migration

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Chinese Science Bulletin 1997年第23期42卷 1970-1974页

作者： liu, LF Xu, xd Mao, DF Yu, HJ Univ Petr Beijing 102200 Peoples R China

IN recent years, studies on nitrogen compounds have been widely carried out by overseas schol-are, and achievements have been obtained spec1ally in the application of carbazoles to thestudy of hydrocarbon migration. B... 详细信息

关键词： carbazole compound hydrocarbon migration Tarim Basin.

THE INTERACTION OF Co（II）， Ni（II）， Cu（II） AND Zn（II） WITH 6－AMINOPENICILLANIC ACID IN AQUEOUS SOLUTION

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Chinese Chemical Letters 1995年第6期6卷 531-532页

作者： Zhang, xd Guan, W liu, QT Yang, P Liaoning Univ Dept Chem Shenyang 110036 Peoples R China Shanxi Univ Dept Chem Taiyuan 030006 Peoples R China

The complex formation equilibria of M2+ ions(M=Co,Ni,Cu,Zn) with 6-aminopenicillanic acid(6-APA)have been studied through potentiometric titrations. The results show that all of metal ions form 1:1 complexes(M(APA)+,N(APA)(OH)) with 6-APA in solution. Formation constants of the complexes were determined at 4O℃in aqueous solution having a fixed ionic Strength(0.1M NaClO4) and cormlated with the second-order rate constants for metal-ion Catalysed hydrolysis of peicillin.

关键词： II Co THE AQUEOUS INTERACTION OF SOLUTION AMINOPENICILLANIC AND ACID Zn Cu Ni

Ductile Phase Toughened Brittle Materials

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Journal of Materials Science & Technology 1996年第2期12卷 124-134页

作者： Sun, xd Yeomans, JA UNIV SURREY DEPT MAT SCI & ENGNGUILDFORD GU2 5XHSURREYENGLAND

Toughening of brittle materials by the inclusion of ductile phases is governed by several important factors which include ceramic-ductile phase interfacial bond strength, physical and chemical compatibility between ceramic and ductile phase, geometry and mechanical properties of ductile phase. The present understanding of the effect of these factors on toughening is reviewed and clarified. Continuous ductile phases (network, fibre or plate) are found to be more efficient for the toughening of brittle materials than discrete ductile particles. However, ductile particle toughened brittle materials have the advantages of material homogeneity, isotropy, and particularly better high temperature properties. It has been demonstrated that the influence of interfacial bond strength is determined by the geometry of the ductile phase in the composites. For the comparatively continuous ductile phase, such as ductile network, fibre or plate, comparatively weak interfacial bond strength can promote partial debonding of the brittle matrix-ductile phase interface during crack propagation and is beneficial for toughening. For discrete particulate ductile phase toughened brittle materials, the small gauge length of the ductile phase often results in the ductile phase pull-out during crack propagation which is the main limitation to toughening. Thus strong bond strength is required to ensure the bridging of the crack by the ductile phase. The coefficient of thermal expansion (CTE) mismatch between matrix and ductile phase has also been correlated with the geometry of the ductile phase. In most of the ceramic/metal systems, the CTE of the ductile metal phase is greater than that of the ceramic matrix. In the case of ductile network, fibre or plate, the residual stress created by the CTE mismatch can contribute to toughening through its influence on the initial crack opening stress while the bridging of the crack by the ductile phase is still ensured. However, for discrete ductile parti

关键词： Brittleness

Shock effects and history of the Yanzhuang meteorite: a case different from L-chondrites

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Chinese Science Bulletin 1997年第22期42卷 1889-1894页

作者： Chen, M Xie, xd Chinese Acad Sci Guangzhou Inst Geochem Guangzhou 510640 Peoples R China

MANY ordinary chondrites contain the networks of black veins with the widths from

关键词： chondrite H-group L-group shock vein shock effect history.

Chemoprevention of tea on colorectal cancer induced by dimethylhydrazine in Wistar rats

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World Journal of Gastroenterology 2000年第5期6卷 699-703页

作者： Jia xd Han C 中国预防医学科学院营养与食品卫生所北京

AIM To investigate the chemopreventiveeffects of green tea and tea pigment on 1,2-dimethylhydrazine(DMH)-induced rat *** Male weaning Wistar rats wererandomly allocated into four *** in thepositive control group were given *** DMH,once a week for ten weeks;rats in tea-treated groups,with the same DMH treatment asin the positive group,received 2% green tea and0.1% tea pigments;rats in the negative controlgroup were given *** of the samevolume of saline as well as DMH in the *** were sacrified and necropsied atthe end of week 16 and week *** Aberrant cryptic foci(ACF)wereformed in animals in DMH-treated groups at theend of week *** to the DMH group,green tea and tea pigments groups had less ACF(148.25 and 204.25,respectively,P<0.01).Atthe end of week 32,all rats in DMH groupdeveloped large intestinal *** resultsalso showed that DMH increased labeling index(LI)of proliferating cell nuclear antigen(PCNA)of intestinal mucosa and the expression of ***,in the tea-treated groups,PCNA-LI was significantly reduced as compared withthe positive control group(36.63 and 40.36 inthe green tea group and tea pigment group,respectively,at the end of the experiment,P<0.01).ras-p21 expression was alsosignificantly reduced(2.07 and 2.36 in the colontumors of rats in the green tea group and teapigments group,respectively at the end of theexperiment,P<0.01).Furthermore,green tea and tea pigment inhibited the expression of Bcl-2protein(2,5,1,0 and 2,4,1,0,respectively,at the end of the experiment P<0.01),andinduced expression of Bax protein(0,1,3,4and 0,1,4,3,respectively,P<0.01).CONCLUSION Chinese green tea drinkinginhibited ACF and colonic tumors formation inrats,which showed that tea had a significantchemopreventive effect on DMH-inducedcolorectal *** effects may bedue to suppression of cell proliferation andinduction of apoptosis in the intestina

关键词： colorectal neoplasms dimethylhydrazine tea apoptosis aberant crypt foci rats proliferating cell nuclear antigen chemoprevention

EURYCARPIN A,A NEW ISOFLAVONE FROM GLYCYRRHIZA EURYCARPA

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Chinese Chemical Letters 1995年第6期6卷 477-478页

作者： Zhang, YM Xu, xd Hu, BH liu, Q Hou, CY liu, YL Yang, JS Chinese Acad Med Sci Inst Med Plant Dev Beijing 100094 Peoples R China

A new isoflavone designated as eurycarpin A(I) has been isolated from the root of Glycyrrhiza eurycarpa P. C. Li. Based on spectroscopic data, its structure was established as 7, 2',4'-trihydroxy-3'(3,3-dimethylallyl)...

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The complex effects of miR-146a in the pathogenesis of Alzheimer's disease

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Neural Regeneration Research 2025年第5期20卷 1309-1323页

作者： Yunfan Long Jiajia liu Yu Wang Haidong Guo Guohong Cui Department of Neurology Shanghai No.9 People’s HospitalShanghai Jiaotong University School of MedicineShanghaiChina Academy of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina School of Integrative Medicine Shanghai University of Traditional Chinese MedicineShanghaiChina Department of Neurology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghaiChina

Alzheimer's disease is a neurodegenerative disorder characterized by cognitive dysfunction and behavioral *** plaques formed through the extracellular deposition of amyloid-βproteins,as well as neurofibrillary tangles formed by the intracellular deposition of hyperphosphorylated tau proteins,comprise two typical pathological features of Alzheimer's *** symptomatic treatment,there are no effective therapies for delaying Alzheimer's disease ***(miR)are small,non-coding RNAs that negatively regulate gene expression at the transcriptional and translational levels and play important roles in multiple physiological and pathological ***,miR-146a,a NF-κB-regulated gene,has been extensively implicated in the development of Alzheimer's disease through several *** has demonstrated substantial dysregulation of miR-146a both during the initial phases and throughout the progression of this *** R-146a is believed to reduce amyloid-βdeposition and tau protein hyperphosphorylation through the TLR/IRAK1/TRAF6 pathway;however,there is also evidence supporting that it can promote these processes through many other pathways,thus exacerbating the pathological manifestations of Alzheimer's *** has been widely reported that miR-146a mediates synaptic dysfunction,mitochondrial dysfunction,and neuronal death by targeting m RNAs encoding synapticrelated proteins,mitochondrial-related proteins,and membrane proteins,as well as other *** the impact on glial cells,miR-146a also exhibits differential *** one hand,it causes widespread and sustained inflammation through certain pathways,while on the other hand,it can reverse the polarization of astrocytes and microglia,alleviate neuroinflammation,and promote oligodendrocyte progenitor cell differentiation,thus maintaining the normal function of the myelin sheath and exerting a protective effect on *** this review,we provide a

关键词： Alzheimer's disease amyloid-β glial cells microRNAs miR-146a neuroinflammatory