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Neutron-irradiated Si by positron annihilation

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Chinese Science Bulletin 1997年第1期42卷 26-30页

作者： Huang, MR Wang, YY Yang, jh He, YS Guo, YH Liu, CC Institute of High Energy Physics Chines Academy of Sciences Beijing China Research Laboratory of Semiconductors Hebei Technological College Tianjing China

SILICON is a quite important material in the application of energy resources technology. With the development of ion-implantation technique and the increasing interest in dopping, it is very important to know the relationship between the vacacies induced by the particle irradiation damage and the annealing temperature. The positron annihilation is a very useful method for studying defects in the semiconductor, because the annihilation characteristics of trapped positron are influenced by the charge of the defects. It has been shown that the positrons can be trapped by defects created by irradi-

关键词： neutron-irradiated Si positron annihilation vacancy.

Diffraction property of photorefractive volume grating in Ce: KNSBN for ordinarily polarized reading beam

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Chinese Science Bulletin 2000年第2期45卷 145-149页

作者： Liang, BL Wang, ZQ Mu, GG Guan, jh Fu, RL Nankai Univ Optoelect Informat Sci & Technol Lab Inst Modern Opt Tianjin 300071 Peoples R China

The diffraction efficiency of volume grating written by two wave mixing in Ce:KNSBN photorefractive crystal versus the writing beam ratio for ordinarily polarized reading beam is experimentally studied. The result is different from that for the extraordinarily polarized reading beam. Then the modified coupled-wave theory is used to fit the experimental data. The theoretical results are coincident with the experimental data quite well. This research gives a significant Support to the applications of Ce:KNSBN crystal in holographic recording and optical information processing.

关键词： photofractive grating diffraction efficiency energy transfer.

Methylene green-mediated sensor highly sensitive to hydrogen peroxide based on entrapment of horseradish peroxidase in composite membrane of regenerated silk fibroin and poly(vinyl alcohol)

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Chinese Journal of Chemistry 1996年第4期14卷 359-366页

作者： Wu, YX Liu, HY Qi, DY Liu, YC Qian, jh Liu, SH Yu, TY Deng, JQ SHANGHAI UNIV DEPT CHEM & CHEM ENGNSHANGHAI 200072PEOPLES R CHINA FUDAN UNIV DEPT MACROMOL SCI & CHEMSHANGHAI 200433PEOPLES R CHINA

A novel composite membrane of poly(vinyl alcohol) and regenerated silk fibroin was employed to immobilize horseradish peroxidase (HRP) and IR was used to give a useful insight into the structure of the composite membrane before and after ethanol treatment. A methylene green-mediated sensor sensitive to hydrogen peroxide was fabricated, based on the composite membrane as immobilization matrix for HRP. Cyclic voltammetry and amperometric measurement were for the first time utilized to demonstrate the suitability of methylene green as an electron transfer mediator between immobilized HRP and a glassy carbon electrode in bioelectrocatalytic reduction of hydrogen peroxide. Performance and characteristics of the sensor were evaluated in respect to response time, detection limit, applied potential and concentration of the mediator. The sensor possesses a variety of characteristics including good sensitivity, rapid response time and low detection of limit of 0.1 mu mol/L.

关键词： sensor poly(vinyl alcohol) regenerated silk fibroin methylene green horseradish peroxidase hydrogen peroxide

Optimal phase estimation with photon-number difference measurement using twin-Fock states of light

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Chinese Physics B 2019年第12期28卷 82-87页

作者： jh Xu J Z Wang A X Chen Y Li G R Jin Key Laboratory of Optical Field Manipulation of Zhejiang Province and Physics Department of Zhejiang Sci-Tech University Hangzhou 310018China Beijing Computational Science Research Center.Beijing 100193 China

Quantum phase measurement with multiphoton twin-Fock states has been shown to be optimal for detecting equal numbers of photons at the output ports of a Mach–Zehnder interferometer(i.e., the so-called single-fringe detection), since the phase sensitivity can saturate the quantum Cramér–Rao lower bound at certain values of phase shift. Here we report a further step to achieve a global phase estimation at the Heisenberg limit by detecting the particle-number difference(i.e., the ?_z measurement). We show the role of experimental imperfections on the ultimate estimation precision with the six-photon twin-Fock state of light. Our results show that both the precision and the sensing region of the ?_z measurement are better than those of the single-fringe detection, due to combined contributions of the measurement outcomes. We numerically simulate the phase estimation protocol using an asymptotically unbiased maximum likelihood estimator.

关键词： foundations of quantum mechanics measurement theory nonclassical interferometry

ROS does not contribute to acute development of nitroglycerine tolerance in rat aortas

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中国病理生理杂志 2010年第A10期26卷 2065-2066页

作者： wonG SL DOING jh LEE HK LEE WY LAU CW Institute of Vascular Medicine and School of Biomedical Sciences Departments of Chemistry and Pharmacy Chinese University of Hong Kong

The development of nitroglycerine tolerance limits its clinical efficacy of nitric oxide(NO)donors. Several cellular mechanisms have been proposed to explain this phenomenon,one of which is an exaggerated production of reactive oxygen specious(ROS).The present study examined whether ROS contribute to the occurrence of nitroglycerine tolerance which is induced

关键词： explain limits xanthine impaired contraction incubation relaxation exposed inhibited markedly

Up-regulation of PIK3CA promotes metastasis in gastric carcinoma

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World Journal of Gastroenterology 2010年第39期16卷 4986-4991页

作者： Liu JF Zhou XK Chen jh Yi G Chen HG Ba MC Lin SQ Qi YC. Institute of Cancer Research Affiliated Tumor Hospital of Guangzhou Medical College Guangzhou 510095 Guangdong Province China. zxkstar@***

AIM:To explore expressions of PIK3CA in the progression of gastric cancer from primary to metastasis and its effects on activation of phosphatidylinositol 3-kinase(PI3K)/Akt ***:mRNA and protein levels of PIK3CA were assessed,respectively,by real-time quantitative polymerase chain reaction and immunohistochemistry in specimens of normal gastric mucosa,primary foci and lymph node and distant metastasis of gastric *** and phosphorylated Akt protein were also examined by Western blotting in these tissues,in order to analyze the effect of PIK3CA expression level changes on the activation of PI3K/Akt signaling ***:PIK3CA mRNA in lymph node metastasis were approximately 5 and 2 folds higher,respectively,than that in the corresponding normal gastric mucosa and primary gastric cancer tissues(P<0.05),while no statistical significance was found compared with distant ***,PIK3CA protein expression was discovered in 7(35%)specimens of 20 primary foci vs 10(67%)of 15 of lymph node metastasis or 11(61%)of 18 of distant metastasis(35%vs 67%,P=0.015;35%vs 61%,P=0.044).With the increased level of PIK3CA expression,the total Akt protein expression remained almost unchanged,but p-Akt protein was upregulated ***:Increased expression of PIK3CA is expected to be a promising indicator of metastasis in gastric ***-regulation of PIK3CA may promote the metastasis of gastric cancer through aberrant activation of PI3K/Akt signaling.

关键词： PIK3CA Phosphatidylinositol 3-kinase/Akt pathway Metastasis Gastric cancer Akt

美国中草药的监管与应用——误用是导致中毒事件的主要原因

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Acupuncture and Herbal Medicine 2024年第2期4卷 159-166,I0002页

作者： Willow jh Liu American Association of Chinese Herbs 美国

中药已经用于预防和治疗疾病超过两千年。它通过中国移民传播到世界各地,帮助了无数患者缓解疾病带来的痛苦。美国和大多数西方国家将中药归类为膳食补充剂。然而,由于一些无知的地方商人滥用少数中药,导致了一些事件,例如与麻黄相关的... 详细信息

中药已经用于预防和治疗疾病超过两千年。它通过中国移民传播到世界各地,帮助了无数患者缓解疾病带来的痛苦。美国和大多数西方国家将中药归类为膳食补充剂。然而,由于一些无知的地方商人滥用少数中药,导致了一些事件,例如与麻黄相关的死亡和含有马兜铃酸的产品相关的肾衰竭,中药的声誉受到了严重损害。许多美国人不知道传统中医、中药和中药草药之间的区别。他们不知道中药的疗效和安全性取决于正确的诊断和辨证、配方、剂量、用药时间以及药材的质量。中药的毒性自《神农本草经》(神农的药材书)以来就有记录,这是2000年前写的第一本关于中药的书,其中将药物根据其安全性分为三类,并自那时起不断记录和更新。包括生殖毒性在内的大多数中药的毒性已列入《中华人民共和国药典》。自上个世纪以来,动物研究已应用于中药。草药的毒性可能在不同动物物种之间有所不同。对正常和疾病诱导的动物进行的研究也可能表现出不同的毒性。此外,科学家们还发现,某些毒性仅对具有特定健康状况和特定基因的某些人群呈现,被称为特异质毒性。本文回顾了中药在美国的应用、教育、研究和监管,并讨论了中药的毒性问题。

关键词：毒性问题疗效和安全性动物物种马兜铃酸《神农本草经》肾衰竭生殖毒性膳食补充剂

医学院校课程整合的经验教训：学生、课程负责人与改革领导者的观点

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复旦教育论坛 2009年第3期7卷 90-92页

作者： Muller jh 汪青复旦大学上海医学院医学教育研究室上海200032

美国医学院校的课程整合改革方兴未艾。加州大学旧金山分校医学院从2001级新生开始对课程体系进行大幅调整,本研究调查了该校参与改革的不同群体,包括教育改革的领导者、受到直接影响的学生、新建课程的负责人等对课程改革的态度,了解... 详细信息

美国医学院校的课程整合改革方兴未艾。加州大学旧金山分校医学院从2001级新生开始对课程体系进行大幅调整,本研究调查了该校参与改革的不同群体,包括教育改革的领导者、受到直接影响的学生、新建课程的负责人等对课程改革的态度,了解其对课程整合实施一年内的成绩和挑战的看法。结果表明,他们对跨学科教学、跨学科系室协作、课程关联的建立、课程内容的排序及框架构建等四个主题有相同的看法,也有不小的分歧。

关键词：课程整合医学教育

Cloning and identification of an angiostatic molecule IP-10/crg-2

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World Journal of Gastroenterology 1999年第3期5卷 241-244页

作者： Liu ZG Yang jh An HZ Wang HY He FT Han ZY Han Y Wu HP Xiao B Fan DM Fourth Mil Med Univ Dept Gastroenterol Xijing Hosp Xian 710032 Shaanxi Prov Peoples R China Harvard Univ Dept Cellular & Mol Biol Cambridge MA 02138 USA

AIM To obtain human and murine cDNAsencoding IFN--y inducible protein 10 (lP--10) andcytokine responsive gene--2 (Crg-2).METHODS The encoding genes of lP-10 and Crg2 were amplified by RT--PCR from Cultured humanfibroblast cells and Balb/ c mouse liver treatedby IFN-y and TNF-a, respectively, and clonedinto plasmids of PUC19 and PGEM3Zf(+ ).RESULTS The nucleotide sequences ot theamplified DNA were confirmed by endonucleasesdigestion and *** Recombinant lP-10/ crg--2 geneclones with 306 hp and 314 hp inserts wereestablished for further research on biologicalactivities and ligands of hiP-10/mCrg--2.

关键词： IP Nature Figure Cloning and identification of an angiostatic molecule IP-10/crg-2