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First Total Synthesis of the Proposed Structures of Orisuaveolines A and B

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Chinese Journal of Chemistry 2013年第1期31卷 123-126页

作者： Jie Zhang Shijun Da Xiaolin Feng Xiaoyi chen Jianhui jiang ying Li State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering Lanzhou University Lanzhou Gansu 730000 China

First total synthesis of the proposed structures of β-indoloquinazoline alkaloids orisuaveolines A and B is re- ported. The key steps of the synthesis included a Pictet-Spengler reaction to build a six-member lactam which fur- ther transformed into target molecular by a one-pot condensation. This synthesis provided an access to the proposed structures of orisuaveolines A and B in a short and convenient manner from inexpensive, commercially available starting materials. The structures of our synthesized products were confirmed by 2D-NMR experiments.

关键词： orisuaveolines A and B indoloquinazoline alkaloids Pictet-Spengler reaction one-pot condensation

Effect of Selenium Supplementation on Activity and mRNA Expression of Type 1 Deiodinase in Mice With Excessive Iodine Intake

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Biomedical and Environmental Sciences 2006年第4期19卷 302-308页

作者： XUE-FENG YANG XIAO-HUI HOU JIAN XW HUAI-LAN GUO chen-jiang ying XIAO-YI chen XIU-FA SUN Department of Nutrition and Food Hygiene School of Public Health Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei China

Objective To investigate the effect of selenium supplementation on the selenium status and selenoenzyme, especially the activity and mRNA expression of type 1 deiodinase （D1） in mice with excessive iodine （EI） intake and to explore the mechanism of selenium intervention on iodine-induced abnormities. Methods Weanling female BALB/c mice were given tap water or 3 mg/L of iodine or supplemented with 0.5 mg/L or 1.0 mg/L of selenium in the presence of excessive iodine for 5 months. Selenium status, thyroid hormone level, hepatic and renal D 1 activity and mRNA expression were examined. Results Excessive iodine intake significantly decreased the selenium concentration in urine and liver, and the activity of glutathione peroxidase （GSH-Px） in liver. Meanwhile, serum total T4 （TT4） increased while serum total T3 （TT3） decreased. Hepatic D1 enzyme activity and mRNA expression were reduced by 33% and 86%, respectively. Renal D1 enzyme activity and mRNA were reduced by 30% and 55%, respectively. Selenium supplementation obviously increased selenium concentration, activity of GSH-Px and D1 as well as mRNA expression of D1. However, increasing the supplementation of Se from 0.5 to 1.0 mg/L did not further increase selenoenzyme activity and expression. Conclusion Relative selenium deficiency caused by excessive iodine plays an essential role in the mechanism of iodine-induced abnormalities. An appropriate dose of selenium supplementation exercises a beneficial intervention.

关键词： Excessive iodine Selenium Glutathione peroxidase Type 1 deiodinase

Establishment of a Stable PrP^(Sc) Panel from Brain Tissues of Experimental Hamsters with Scrapie Strain 263K

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Biomedical and Environmental Sciences 2009年第2期22卷 151-156页

作者： BAO-YUN ZHANG CHAN TIAN JUN HAN chen GAO QI SHI JIAN-MING chen HUI-ying jiang WEI ZHOU AND XIAO-PING DONG State Key Laboratory for Infectious Disease Prevention and Control National Institute for Viral Disease Control and Prevention Chinese Center for Disease Control and Prevention Beijing 100052 China

Objective To establish a stable PrP^Sc panel from brain tissues of experimental hamsters infected with scrapie agent 263K for evaluating diagnostic techniques of human and animals＇ prion diseases. Methods Thirty brain tissue samples from hamsters intracerebrally infected with scrapie strain 263K and another 30 samples from normal hamsters were selected to prepare 10%, 1%, and 0.5% brain homogenates, which were aliquoted into stocks. PrP^Sc in each brain homogenate was determined by proteinase K digestions followed by Western blot assay and partially by immunohistochemistry. Stability and glycoforms of PrP^Sc were repeatedly detected by prp^SC-specific Western blots in half a year and 3 years later. Results PrPsc signals were observed in all 10% brain homogenates of infected hamsters. Twenty out of 30 stocks and 19 out of 30 stocks were PrPsc positive in 1% and 0.5% brain homogenatesof infected hamsters, respectively. TWenty-seven out of 30 stocks presented three positive bands in 10% brain homogenates, whereas none of 1% and 0.5% homogenates contained 3 bands. The detection of prpSc-specific signals stored in half a year and 3 years later demonstrated that the ratio of PrPsc positive samples and glycoforms was almost unchanged. All normal hamsters＇ brain homogenates were PrP^Sc negative. Conclusion A PrP^Sc panel of prion disease can be established, which displays reliably stable prp^Sc-specific signals and glycoforms.

关键词： TSE prp^Sc Panel Glycoforms Stability

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功能梯度压电旋转圆环的三维解析解

深圳大学学报（理工版） 2009年第3期26卷 321-326页

作者：陈江瑛翁国飞丁皓江宁波大学机械工程与力学学院宁波315211 浙江大学建筑工程学院杭州310027

基于三维压电弹性力学方程,采用直接位移法,给出横观各向同性功能梯度压电旋转圆环的三维解析解.设功能梯度压电材料参数是厚度坐标z的任意函数,广义位移分量是径向坐标r的幂函数的线性组合,其中含有9个待定的位移函数,它们是坐标z的函... 详细信息

基于三维压电弹性力学方程,采用直接位移法,给出横观各向同性功能梯度压电旋转圆环的三维解析解.设功能梯度压电材料参数是厚度坐标z的任意函数,广义位移分量是径向坐标r的幂函数的线性组合,其中含有9个待定的位移函数,它们是坐标z的函数.结合相应的边界条件,求解控制方程,通过直接积分确定位移函数和相应的积分常数,从而确定旋转圆环的力场和电场.算例展示一种材料的梯度指标对力场和电场的影响.

关键词：压电材料功能梯度旋转圆环三维解析解位移法

Toward understanding the role of genomic repeat elements in neurodegenerative diseases

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Neural Regeneration Research 2025年第3期20卷 646-659页

作者： Zhengyu An Aidi jiang Jingqi chen Institute of Science and Technology for Brain-Inspired Intelligence Fudan UniversityShanghaiChina MOE Frontiers Center for Brain Science Fudan UniversityShanghaiChina MOE Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence Fudan UniversityShanghaiChina Zhangjiang Fudan International Innovation Center ShanghaiChina

Neurodegenerative diseases cause great medical and economic burdens for both patients and society;however, the complex molecular mechanisms thereof are not yet well understood. With the development of high-coverage sequencing technology, researchers have started to notice that genomic repeat regions, previously neglected in search of disease culprits, are active contributors to multiple neurodegenerative diseases. In this review, we describe the association between repeat element variants and multiple degenerative diseases through genome-wide association studies and targeted sequencing. We discuss the identification of disease-relevant repeat element variants, further powered by the advancement of long-read sequencing technologies and their related tools, and summarize recent findings in the molecular mechanisms of repeat element variants in brain degeneration, such as those causing transcriptional silencing or RNA-mediated gain of toxic function. Furthermore, we describe how in silico predictions using innovative computational models, such as deep learning language models, could enhance and accelerate our understanding of the functional impact of repeat element variants. Finally, we discuss future directions to advance current findings for a better understanding of neurodegenerative diseases and the clinical applications of genomic repeat elements.

关键词： Alzheimer's disease ataxia deep learning long-read sequencing neurodegeneration neurodegenerative diseases Parkinson's disease repeat element structural variant

英语高考制度改革对大学英语课程政策执行的挑战与应对

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东北师大学报（哲学社会科学版） 2017年第1期 184-188页

作者：江臣杨颖秀东北师范大学外国语学院吉林长春130024 东北师范大学教育学部吉林长春130024

新一轮高考制度改革中英语科目的改革方案备受热议,政策调整产生的变化不仅对基础教育英语教学产生强大的导向性,对高校也会产生后续效应,特别是对大学英语课程政策执行带来诸多挑战。笔者在对英语高考制度改革解读的基础上,总结新政策... 详细信息

新一轮高考制度改革中英语科目的改革方案备受热议,政策调整产生的变化不仅对基础教育英语教学产生强大的导向性,对高校也会产生后续效应,特别是对大学英语课程政策执行带来诸多挑战。笔者在对英语高考制度改革解读的基础上,总结新政策对学生英语学习产生的消极影响,进而指出这些影响对大学英语课程政策执行提出的挑战,并就如何应对挑战提出相应的实施建议。

关键词：英语高考制度大学英语课程政策执行

Targeting STAT3 with SH-4-54 suppresses stemness and chemoresistance in cancer stem-like cells derived from colorectal cancer

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World Journal of Clinical Oncology 2025年第2期16卷 63-75页

作者： Xu-Fan Zhang Qian chen Qin jiang Qiong-ying Hu Department of Nuclear Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 641000Sichuan ProvinceChina College of Medical Technology Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina Department of Laboratory Medicine Hospital of Mianyang Traditional Chinese MedicineChengdu 641000Sichuan ProvinceChina Department of Laboratory Medicine Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072Sichuan ProvinceChina

BACKGROUND Over the years,the numbers of treatment options for colorectal cancer(CRC)have increased,leading to notable improvements in the overall survival of CRC *** therapy may initially yield positive results,the development of drug resistance can result in treatment failure and cancer *** resistance is often attributed to the presence of cancer stem cells(CSCs).These CSCs not only contribute to therapeutic resistance but also play crucial roles in the initiation and development of tumor *** To investigate the antitumor effects of SH-4-54,which are mediated by targeting CSCs relative to treatment *** CSCs were enriched by culturing CRC cells in serum-free *** of stemness and IL-6/JAK2/STAT3 signaling were detected by Western *** of CSC malignancy,including proliferation,invasion,and tumor formation,were *** In this study,we employed SH-4-54,which exhibits anticancer activity in solid tumors through targeting the SH2 domain of both the signal transducer and activator of transcription(STAT)3 and the STAT5,and evaluated its effects on stemness and chemoresistance in colorectal *** expected,SH-4-54 treatment inhibited the phosphorylation of STAT3(p-STAT3)and decreased the percentage of ALDH1A1-positive CRC *** addition of SH-4-54 dissociated colorectal spheroids and decreased the expression of stemness markers,including ALDH1A1,CD44 and ***-4-54 treatment decreased IL-6/JAK2/STAT3 signaling by inhibiting p-STAT3 and thus inhibited spheroid formation by SW480 and LoVo ***,SH-4-54 treatment inhibited indicators of malignancy,including cell proliferation,invasion,and tumor formation,in CSCs in vitro and in ***,SH-4-54 treatment significantly increased chemosensitivity to *** Taken together,these results indicate that SH-4-54 is a promising molecule that exerts antitumor effects on colorectal CSCs by inhibiting STAT3 signaling.

关键词： SH-4-54 Colorectal cancer Cancer stem-like cells Stemness Chemosensitivity

Effects of Bifidobacterium lactis BLa80 on fecal and mucosal flora and stem cell factor/c-kit signaling pathway in simulated microgravity rats

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World Journal of Gastroenterology 2025年第1期31卷 93-109页

作者： Ping Zhang ying Zhu Pu chen Tong Zhou Zhe-Yi Han Jun Xiao Jian-Feng Ma Wen Ma Peng Zang ying chen Graduate School Hebei North UniversityZhangjiakou 075000Hebei ProvinceChina Key Laboratory of Aerospace Nutrition and Food Engineering China Astronaut Research and Training CenterBeijing 100094China Department of Gastroenterology The Air Force Medical CenterBeijing 100142China Department of Blood Transfusion Air Force Medical CenterBeijing 100142China

BACKGROUND Simulated microgravity environment can lead to gastrointestinal motility *** pathogenesis of gastrointestinal motility disorders is closely related to the stem cell factor(SCF)/c-kit signaling pathway associated with intestinal flora and Cajal stromal ***,intestinal flora can also affect the regulation of SCF/c-kit signaling pathway,thus affecting the expression of Cajal stromal *** cells are the pacemakers of gastrointestinal *** To investigate the effects of Bifidobacterium lactis(***)BLa80 on the intestinal flora of rats in simulated microgravity and on the gastrointestinal motility-related SCF/c-kit *** The internationally recognized tail suspension animal model was used to simulate the microgravity environment,and 30 rats were randomly divided into control group,tail suspension group and drug administration tail suspension group with 10 rats in each group for a total of 28 *** tail group was given *** BLa80 by intragastric administration,and the other two groups were given water intragastric administration,the concentration of intragastric administration was 0.1 g/mL,and each rat was 1 mL/***&eosin staining was used to observe the histopathological changes in each segment of the intestine of each group,and the expression levels of SCF,c-kit,extracellular signal-regulated kinase(ERK)and p-ERK in the gastric antrum of each group were detected by Western blotting and *** fecal flora and mucosal flora of rats in each group were detected by 16S *** Simulated microgravity resulted in severe exfoliation of villi of duodenum,jejunum and ileum in rats,marked damage,increased space between villi,loose arrangement,shortened columnar epithelium of colon,less folds,narrower mucosal thickness,reduced goblet cell number and crypts,and significant improvement after probiotic *** microgravity reduced the expressions of SCF and c-kit,and increased the express

关键词： Simulated microgravity Rat Intestinal flora Gastrointestinal motility Stem cell factor/c-kit signaling pathway

美国注册学徒制职业培训新政解读:困境与变革

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外国教育研究 2011年第10期38卷 75-79页

作者：陈圆蒋颖重庆大学建设管理与房地产学院重庆400045 共青团重庆市委青少年部重庆400015

注册学徒制作为提高劳动力素质、培养合格技术工人的重要形式,在许多发达国家广泛实施。美国推行注册学徒制时间长、范围广,在培训方式、运行管理等方面形成具代表性、典型性的较为完善的体系。为适应社会经济发展需要,克服部分企业投... 详细信息

注册学徒制作为提高劳动力素质、培养合格技术工人的重要形式,在许多发达国家广泛实施。美国推行注册学徒制时间长、范围广,在培训方式、运行管理等方面形成具代表性、典型性的较为完善的体系。为适应社会经济发展需要,克服部分企业投入乏力、优良师资匮乏、注册认证程序繁琐和培训时间过长等问题,美国政府从2008年起通过增加资金投入、创新培训模式、强化绩效评估等举措,推行注册学徒制新政。解析美国注册学徒制的实际运行和发展态势,对于促进我国职业教育和培训工作,具有一定的参考价值。

关键词：美国注册学徒制职业培训困境变革