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冬枣果实中微量元素和重金属含量研究

光谱学与光谱分析 2008年第8期28卷 1928-1930页

作者：芮玉奎申琳生吉萍中国农业大学资源与环境学院北京100094 中国农业大学食品科学与营养工程学院北京100083

食品中微量元素和重金属含量已经成为食品研究中的两个热点。文章选用鲜冬枣果实作为材料,通过ICP-MS研究了冬枣中微量元素和重金属的含量。结果显示,冬枣中含有丰富的微量元素,尤其是钙(126.67μg·g-1·FW)、镁(68.04μg·g-1·FW)、... 详细信息

食品中微量元素和重金属含量已经成为食品研究中的两个热点。文章选用鲜冬枣果实作为材料,通过ICP-MS研究了冬枣中微量元素和重金属的含量。结果显示,冬枣中含有丰富的微量元素,尤其是钙(126.67μg·g-1·FW)、镁(68.04μg·g-1·FW)、锶(1691.39ng·g-1·FW)、锌(787.26ng·g-1·FW)、铁(512.84ng·g-1·FW)、锰(495.42ng·g-1·FW)和钼(33.38ng·g-1·FW)等,这些元素对于维护人体健康和长寿具有积极作用。重金属含量普遍较低,符合国家相关行业标准。所以冬枣果实如果在无污染的地区种植,是一种营养丰富和安全的鲜食食品。

关键词：冬枣 ICP-MS 微量元素重金属

STRUCTURE DESIGN OF THE BEIjiNG SPECTROMETERⅢBEAM PIPE

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Chinese Journal of Mechanical Engineering 2008年第3期21卷 1-6页

作者： ZHENG Lifang ji Quan WANG Li LI xunfeng XU Shaowang dong Sujun ZHAO Libin LIU jianping School of Mechanical Engineering University of Science and Technology Beijing Beijing 100083 China Institute of High Energy Physics Chinese Academy of Sciences Beijing 100049 China Department of Flight Vehicle Design and Applied Mechanics Beihang University Beijing 100083 China School of Mechanical Engineering Tianjin University Tianjin 300072 China

The Beijing spectrometer Ⅲ （BESⅢ） beam pipe is in the center of the BESⅢ, which is the detector of the upgrade project of Beijing electron and positron collider （BEPC Ⅱ）. Electrons and positrons collide in the BESⅢ beam pipe. According to the demands of the BEPC Ⅱ, a key program of Chinese Academy of Sciences, the BESⅢ beam pipe is designed based on the finite elements analysis. The BESIII beam pipe is installed in the inner cylinder of the BESⅢ drift chamber. As a vacuum tube, the BESIII beam pipe is designed as 1 000 mm in length, 63 mm in inner diameter and 114 mm in outer diameter, respectively. The BESIII beam pipe consists of a central beryllium pipe cooled by EDM-1, the oil No.1 for electric discharge machining, and two extended copper pipes cooled by deionized water （DW）. The three parts are jointed by vacuum welding. Factors taken into account in the design are as follows. ① The wall thickness of the central beryllium pipe should be designed as small as possible to reduce the multi-scattering and improve the particle momentum resolution. And the wall thickness of the extended copper pipe should be designed as large as possible to protect the detectors from the backgrounds. ②The BESⅢ beam pipe must be sufficiently cooled to avoid the damage and prevents its influence to the BESⅢ drift chamber （DC） operation. The inner surface temperature of the DC inner cylinder must be maintained at 293±2 K. ③ The magnetic permeability of the materials used in the BESⅢ beam pipe must be less than 1.05 H/m to avoid large magnetic field distortions. ④ The static pressure of the vacuum chamber of the BESⅢ beam pipe must be less than 800 μPa. The simulating results show that the designed structure of the BESⅢ beam pipe satisfies the requirements mentioned above. The structure design scheme is evaluated and adonted hv the headouarters of BEPCⅡ.

关键词： Beam pipe Beijing spectrometer Ⅲ Structure design Beijing electron and positron collider Ⅱ BESⅢ

AN EXPERIMENTAL STUDY OF FLOW FIELD IN THE FLUID HOMOGENIZER

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Journal of Hydrodynamics 1997年第2期9卷 94-98页

作者： Su Yong-sheng, ji Chu-yingEast China University of Science and Technology, shanghai 200237, P. R. China

A Laser Doppler Anemometer (LDA) is used to measure and study the flow field in the working chamber of a homogenizer. Flow Patterns, distributions of mean and fluctuating velocities, shear rates are obtained in details. The characteristics of the flow field and the basic principles of homogenizing are presented. These results are very helpful for the improvement of fluid homogenizers.

关键词： flow homogenizer Laser Doppler Anemometer

Alanine racemase is essential for the growth and interspecies competitiveness of Streptococcus mutans

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International Journal of Oral Science 2016年第4期8卷 231-238页

作者： Yuan Wei Wei Qiu Xue-dong Zhou Xin Zheng Ke-Ke Zhang Shi-Da Wang Yu-Qing Li Lei Cheng ji-Yao Li Xin Xu Ming-Yun Li State Key Laboratory of Oral Diseases West China Hospital of Stomatology Sichuan University Department of Operative Dentistry and Endodontics West China Hospital of Stomatology Sichuan University

D-alanine （D-Ala） is an essential amino acid that has a key role in bacterial unique enzyme that interconverts L-alanine and D-alanine in most bacteria, antimicrobial drug development. Streptococcus mutans is a major causative cell wall synthesis. Alanine racemase （Air） is a making this enzyme a potential target for factor of dental caries. The factors involved in the survival, virulence and interspecies interactions of S. mutans could be exploited as potential targets for caries control. The current study aimed to investigate the physiological role of Air in S. mutans. We constructed air mutant strain of S. mutans and evaluated its phenotypic traits and interspecies competitiveness compared with the wild-type strain. We found that air deletion was lethal to S. mutans. A minimal supplement of D-Ala （150 ***- 1） was required for the optimal growth of the air mutant. The depletion of D-alanine in the growth medium resulted in cell wall perforation and cell lysis in the air mutant strain. We also determined the compromised competitiveness of the air mutant strain relative to the wild-type S. mutans against other oral streptococci （S. sanguinis or S. gordonil~, demonstrated using either conditioned medium assays or dual-species fluorescent in situ hybridization analysis. Given the importance and necessity of air to the growth and competitiveness of S. mutans, Air may represent a promising target to modulate the cariogenicity of oral biofilms and to benefit the management of dental caries.

关键词： alanine racemase biofilm D-alanine dental caries Streptococcus mutans

Immunostaining of PD-1/PD-Ls in liver tissues of patients with hepatitis and hepatocellular carcinoma

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World Journal of Gastroenterology 2011年第28期17卷 3322-3329页

作者： Bao-Ju Wang Jun-jie Bao Jun-ZhongWang Yang Wang Min jiang Ming-You Xing Wan-Guang Zhang Jun-Ying Qi Michael Roggendorf Meng-ji Lu dong-Liang Yang Division of Clinical Immunology TongjiHospital of Tongji Medical College Huazhong University of Sci-ence and Technology Wuhan 430030 Hubei Province China Department of Clinical Laboratory GuangzhouWomen and Children＇s Medical Center Guangzhou 510055Guangdong Province China Department of Microbiology TongjiMedical College Huazhong University of Science and Technol-ogy Wuhan 430015 Hubei Province China Department of Infectious Disease Tongji Hospital of Tongji Medical College Huazhong Universityof Science and Technology Wuhan 430030 Hubei ProvinceChina Hepatic Surgery Center Tongji Hospitalof Tongji Medical College Huazhong University of Science andTechnology Wuhan 430030 Hubei Province China Institute of Virology Univer-sity Hospital Essen Hufelandstrasse 55 45122 Essen Germany

AIM: To investigate the expression of programmed death (PD)-1,PD ligand 1 (PD-L1) and PD-L2 in liver tissues in the context of chronic hepatitis and hepatocellular carcinoma (HCC).METHODS: Liver biopsies and HCC specimens from patients were collected and histologically *** expression of PD-1,PD-L1,and PD-L2 in biopsy specimens of chronic hepatitis and HCC specimens was evaluated by immunohistochemical *** association between the expression level of PD-1,PD-L1,and PD-L2 and clinical and pathological variables was analyzed ***: Expression of PD-1 was found in liverinfiltrating *** contrast,PD-L1 and PD-L2 were expressed in non-parenchyma liver cells and tumor *** expression of PD-L1 was significantly correlated with hepatitis B virus infection (1.42 ± 1.165 vs 0.50 ± 0.756,P = 0.047) and with the stage of HCC (7.50 ± 2.121 vs 1.75 ± 1.500 vs 3.00 ± 0.001,P = 0.018).PD-1 and PD-Ls were significantly up-regulated in HCC specimens (1.40 ± 1.536 vs 5.71 ± 4.051,P = 0.000;1.05 ± 1.099 vs 4.29 ± 3.885,P = 0.004;1.80 ± 1.473 vs 3.81 ± 3.400,P = 0.020).CONCLUSION: PD-L1 may contribute to negative regulation of the immune response in chronic hepatitis ***-1 and PD-Ls may play a role in immune evasion of tumors.

关键词： Hepatitis B virus Programmed death-1 Programmed death ligands Hepatitis Hepatocellular carcinoma

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■方鼎铭文及相关历史问题探析

宝鸡文理学院学报（社会科学版） 2024年第4期44卷 16-22,30页

作者：李春利徐永胜辽宁师范大学历史文化学院辽宁大连116081

■族是商周时期的大族,传世青铜器众多.■族青铜器分布范围广泛,记载了众多历史事实.以辽西地区出土的■方鼎为例,通过对其铭文进行释读,与同期■族青铜器进行比较,并结合商代甲骨卜辞文献,可以对方鼎铭文隐含的相关问题进行探析与解读.

关键词： ■方鼎铭文地望 ■侯亚疑

A Clinical Investigation into the Factors Influencing the Prognosis of Patients with Primary Liver Cancer after Hepatectomy

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临床军医杂志 2005年第2期33卷 133-136页

作者： ji Xi-qing Li Chao-long sheng Xing-hua DepartmentofGeneralSurgery the285thHospitalofPLAHandan056001 DepartmentofHepatobiliarySurgery NanfangHospitalFirstMilitaryMedicalUniversityGuangzhou510515China

Objective To explore the factors influencing the prognosis of patients with primary liver cancer(PLC) after hepatectomy on purpose to provide the preventive measures for improving the long-term *** All of the 189 patients who underwent hepatectomy with PLC from May,1994 to January,1998 were included by reviewing their clinical pathological characteristics and treatments. Totally, 22 factors contributed to the long-term survival rate(SR)and the disease-free SR were analysed . All patients were followed up at least 5 years. Results The 3- and 5-year cumulative SRs in the total group were 63% and 45% respectively. The 3- and 5-year SRs and disease-free SRs in the curative resection (CR) group (n=162) were 67%,47%,and 45% and 26% respectively. It was showed that the way by which a tumor was found, tumor size, portal thrombi, satellite nodule, cirrhosis type, TNM stage, tumor envelope, recurrence and treatment, vascular exclusion and transfusion, differentiation grade and CR were prognostic factors by individual variable analysis. A multivariable analysis showed that CR , tumor size and reoperation were significant factors associated with the prognosis. Conclusion The type of CR and tumor size are determinants influencing the prognosis. Early diagnosis of small carcinoma and CR as soon as possible is essential to improving the prognosis of PLC. Avoiding transfusion and controlling the progress of cirrhosis are expected to improve the disease-free SR.

关键词：肝癌预后肝切除术治疗

基于内聚力失效微观单胞模型的树脂砂拉伸性能的数值研究

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铸造 2019年第4期68卷 364-371页

作者：冀运东郑凯东王遥钟飞升曹东风武汉理工大学材料科学与工程学院湖北武汉430070 武汉理工大学材料复合新技术国家重点实验室湖北武汉430070 彰武县联信铸造硅砂有限公司辽宁阜新123200

原砂粒度及分布、树脂膜厚度和空隙分布构成树脂砂微细观结构特征决定着树脂砂宏观力学行为。针对原砂/树脂间弱界面脱粘与树脂基体失效这两种失效模式,构建了基于断裂力学微细观单胞模型,研究了树脂砂微观结构的失效/断裂演化机制,以及... 详细信息

原砂粒度及分布、树脂膜厚度和空隙分布构成树脂砂微细观结构特征决定着树脂砂宏观力学行为。针对原砂/树脂间弱界面脱粘与树脂基体失效这两种失效模式,构建了基于断裂力学微细观单胞模型,研究了树脂砂微观结构的失效/断裂演化机制,以及3类微观结构(即:树脂包覆层厚度,砂粒直径和粒径级配)对于树脂砂宏观力学行为的影响。计算结果表明,所构建的数值模型能够考虑裂纹尖端的应力集中以及砂粒弧面的几何效应,具备描述在拉伸载荷下树脂砂界面损伤/界面裂纹扩展以及树脂包覆层的内聚失效行为的能力,为树脂砂失效断裂机理的研究提供了一种更加直接有效的工具;微细观结构对树脂砂拉伸力学性能影响研究表明,树脂包覆层厚度、砂粒直径和粒径级配对树脂砂的拉伸强度、比强度、拉伸刚度以及极限拉伸变形量有着不同程度的影响。

关键词：树脂砂微细观结构单胞模型断裂机理

SYMMETRICALCONTINUATIONTECHNIQUEANDITSAPPLICATIONINSTRAIGHTNESSERRORSEPARATION

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Journal of Shanghai jiaotong university(Science) 1996年第1期1卷 34-37页

作者： ji-Shun Li Mai-sheng Hong Bing-Yuan Xue

ＳＹＭＭＥＴＲＩＣＡＬＣＯＮＴＩＮＵＡＴＩＯＮＴＥＣＨＮＩＱＵＥＡＮＤＩＴＳＡＰＰＬＩＣＡＴＩＯＮＩＮＳＴＲＡＩＧＨＴＮＥＳＳＥＲＲＯＲＳＥＰＡＲＡＴＩＯＮＬｉＪｉｓｈｕｎＨｏｎｇＭａｉｓｈｅｎｇＸｕｅＢｉｎｇｙｕａ... 详细信息

ＳＹＭＭＥＴＲＩＣＡＬＣＯＮＴＩＮＵＡＴＩＯＮＴＥＣＨＮＩＱＵＥＡＮＤＩＴＳＡＰＰＬＩＣＡＴＩＯＮＩＮＳＴＲＡＩＧＨＴＮＥＳＳＥＲＲＯＲＳＥＰＡＲＡＴＩＯＮＬｉＪｉｓｈｕｎＨｏｎｇＭａｉｓｈｅｎｇＸｕｅＢｉｎｇｙｕａｎ（ＤｅｐａｒｔｍｅｎｔｏｆＭｅｃ...

关键词： symmetrical continuation three-point method measurement of straightness error separation