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Chinese Chemical Letters 2006年第11期17卷 1511-1514页

作者： Li Gang REN xiang Yang liu yi GU State Key Laboratory of Polymeric Materials Engineering College of Polymer Science and Engineering Sichuan University Chengdu 610065

A novel diamine 4-[（4＇-butoxyphenoxy）carbonyl]phenyl-3＂,5＂-diaminobenzoate （BCDA） was synthesized from 4-butoxyphenol, 4-hydroxybenzoic acid and 3,5-dinitrobenzoic acid through four main intermediates, and a series of polyimides were also synthesized. All the intermediates and the final product were characterized by FTIR and 1H-NMR. The key step in synthesis route is selective hydrolyzation of two ester groups in 4-butoxyphenyl-4＇-acetoxybenzoate, by adjusting the reaction temperature and the concentration of ammonia, shorteding the reaction time. The properties of the novel polyimides, such as the aggregation structures, glass transition temperature, solubility and the pretilt angles, were carded out.

关键词： Synthesis polyimides side chain alignment film.

Ultra-early amplitude decrement after repetitive nerve stimulation supports early neuromuscular junction injury in amyotrophic lateral sclerosis:a prospective cross-sectional study

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Neural Regeneration Research 2022年第3期17卷 655-660页

作者： Jing-Yue Ma xiang-yi liu Shuo Zhang Dong-Sheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina

The dying-back hypothesis holds that the damage to neuromuscular junctions and distal axons in amyotrophic lateral sclerosis occurs at the earliest stage of the *** basic studies have confirmed early damage to neuromuscular junctions,but it is difficult to obtain such evidence directly in clinical *** this prospective cross-sectional study,we recruited 22 patients with early amyotrophic lateral sclerosis with disease duration < 12 months and with clinical symptoms limited to the upper *** also recruited 32 healthy *** nerve stimulation was performed,and patients were followed for 12 *** found a significant change in the response to repetitive nerve stimulation in amyotrophic lateral sclerosis patients without spontaneous electromyographic *** that were prone to denervation had an increased decrement response of target muscles after repetitive nerve *** results suggest that changes in response to repetitive nerve stimulation may occur before denervation in amyotrophic lateral sclerosis *** damage to lower motor neurons is more obvious in patients with a higher percentage of repetitive never stimulation-related amplitude *** study was approved by the Institutional Ethics Committee of Peking University Third Hospital(approval No.M2017198) on August 24,2017.

关键词： amplitude decremental response amyotrophic lateral sclerosis dying-back hypothesis motor neuron disease nerve electrophysiology physiopathology prognosis repetitive nerve stimulation

Promising application of a new ulnar nerve compound muscle action potential measurement montage in amyotrophic lateral sclerosis:a prospective cross-sectional study

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Neural Regeneration Research 2023年第4期18卷 908-912页

作者： yi-Xuan Zhang Jing-Yue Ma xiang-yi liu Shuo Zhang Zhou Yu Dong-Sheng Fan Department of Neurology Peking University Third HospitalBeijingChina Beijing Municipal Key Laboratory of Biomarker and Translational Research in Neurodegenerative Diseases BeijingChina Key Laboratory for Neuroscience National Health Commission/Ministry of EducationPeking UniversityBeijingChina

Previous studies have shown that ulnar nerve compound muscle action potential recorded by the conventional“belly-tendon”montage does not accurately and completely reflect the action potential of the ulnar nerve dominating the abductor digiti minimi muscle due to the effects of far-field potentials of intrinsic hand muscles.A new method of ulnar nerve compound muscle action potential measurement was developed in 2020,which adjusts the E2 electrode from the distal tendon of the abductor digitorum to the middle of the back of the proximal *** new method may reduce the influence of the reference electrode and better reflect the actual ulnar nerve compound muscle action *** this prospective cross-sectional study,we included 64 patients with amyotrophic lateral sclerosis and 64 age-and sex-matched controls who underwent conventional and novel ulnar nerve compound muscle action potential measurement between April 2020 and May 2021 in Peking University Third *** compound muscle action potential waveforms recorded by the new montage were unimodal and more uniform than those recorded by traditional *** the controls,no significant difference in the compound muscle action potential waveforms was found between the traditional montage and new montage *** amyotrophic lateral sclerosis patients presenting with abductor digiti minimi spontaneous activity and muscular atrophy,the amplitude of compound muscle action potential-pE2 was significantly lower than that of compound muscle action potential-dE2(P<0.01).Using the new method,damaged axons were more likely to exhibit more severe amplitude decreases than those measured with the traditional method,in particular for patients in early stage amyotrophic lateral *** addition,the decline in compound muscle action potential amplitude measured by the new method was correlated with a decrease in Revised Amyotrophic Lateral Sclerosis Functional Rating Scale *** findings suggest tha

关键词： amyotrophic lateral sclerosis axonal degeneration biomarker compound muscle action potential distal E2 electrode early diagnosis far field potential nerve electrophysiology prognosis evaluation proximal E2 electrode ulnar motor nerve conduction

Clinical features and therapeutic strategies of obstructive azoospermia in patients treated by bilateral inguinal hernia repair in childhood

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Asian Journal of Andrology 2014年第5期16卷 745-748,I0010页

作者： xiang-Feng Chen Hong-xiang Wang yi-Dong liu Kai Sun Li-Xin Zhou yi-Ran Huang Zheng Li Ping Ping Department of Urology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai Institute of Andrology Shanghai China

Childhood inguinal herniorrhaphy is one common cause of seminal tract obstruction. Vasovasostomy （VV） can reconstruct seminal deferens and result in appearance of sperm and natural pregnancy in some patients. Secondary epididymal obstruction caused by a relatively long-term vasal obstruction is a common cause of lower patency compared with VV due to vasectomy in adults. From July 2007 to June 2012, a total of 62 patients, with history of childhood inguinal herniorrhaphy and diagnosed as obstructive azoospermia were treated in our center. The overall patency rate and natural pregnancy rate were 56.5% （35/62） and 25.8% （16/62）, respectively. 48.4% （30/62） of the patients underwent bilateral VV in the inguinal region, with a patency rate of 76.7% （23/30） and a natural pregnancy rate of 36.7% （11/30）, respectively. 30.6% （19/62） of the patients underwent bilateral VV and unilateral or bilateral vasoepididymostomies due to ipsilateral epididymal obstruction with the patency and natural pregnancy rate decreasing to 63.2% （12/19） and 26.3% （5/19）. 21.0% （13/62） of the patients merely underwent vasal exploration without reconstruction due to failure to find distal vasal stump, etc. Our study indicate that microsurgical reanastomosis is an effective treatment for some patients with seminal tract obstruction caused by childhood inguinal herniorrhaphy.

关键词： azoospermia inguinal herniorrhaphy microsurgical reanastomosis

Elimination of HBr from CH_3Br by Cu^+ and Au^+:A DFT study

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Chinese Chemical Letters 2008年第7期19卷 881-884页

作者： Tao Hong Li Chuan Ming Wang xiang yi liu Xiao Guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 China Department of Chemistry Yunnan University Kunming 650091 China

The elimination of HBr from CH3Br by ground state of Cu＋ and Au＋ has been investigated by using DFT methods. A mechanism of one-step HBr elimination leading to CuCH2＋ was identified. For the formation of AuCH2＋, besides the one-step mechanism, another two-step HBr elimination pathway through a C-Br bond insertion intermediate was also found, and this pathway is energetically more favorable than the one-step mechanism. The calculated reaction energy barriers show that the formation of AuCH2＋ is energetically much more favorable than the formation of CuCH2＋. The experimental observations are well explained.

关键词： Copper and gold Alkyl halide HBr elimination

A computational study on the gas phase reaction of Os^+ with N_2O

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Chinese Chemical Letters 2009年第8期20卷 1010-1014页

作者： Tao Hong Li Chuan Ming Wang Shi Wen Yu xiang yi liu Hui Fu Xiao Guang Xie Faculty of Chemistry Southwest Forestry University Kunming 650224 China Department of Biology Honghe University Menzi 661100 PR China Department of Chemistryl Qujing Normal University Qujing 650011 China Department of Chemistry Yunnan University Kunming 650091 China

The reaction of Os^＋（^6D, ^4F） with N20 has been investigated at B3LYP/TZVP and CCSD（T）/6-311＋G^＊ levels of theory. The mechanisms corresponding to O-atom and N-atom transfer reactions have been revealed. It was found that on the sextet reaction surface both the O-atom and N-atom transfer reactions undergo through direct-abstraction mechanism, leading to the formation of OsO^＋ and OsN^＋, whereas on quartet surface the two reactions undergo through O-N bond or N-N bond insertion mechanism. The calculated energetics shows that the reactions on the sextet surface have notable energy barriers, whereas the reactions on quartet surface are barrierless. ？2009 Xiao Guang Xie. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved.

关键词： O-Atom transfer N-Atom transfer Abstraction Insertion

2,3-Butanediol from the leachates of pine needles induces the resistance of Panax notoginseng to the leaf pathogen Alternaria panax

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Plant Diversity 2023年第1期45卷 104-116页

作者： Tian-Yao Li Chen Ye yi-Jie Zhang Jun-Xing Zhang Min Yang Xia-Hong He Xin-Yue Mei yi-xiang liu You-Yong Zhu Hui-Chuan Huang Shu-Sheng Zhu School of Agriculture Yunnan UniversityKunming650500China State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan Yunnan Agricultural UniversityKunming650201China Key Laboratory of Agro-Biodiversity and Pest Management of Education Ministry of China Yunnan Agricultural UniversityKunming650201China Southwest Forestry University Kunming650224China

Compared with the use of monocultures in the field,cultivation of medicinal herbs in forests is an effective strategy to alleviate *** interactions between herbs and trees play an important role in disease suppression in *** evaluated the ability of leachates from needles of Pinus armandii to induce resistance in Panax notoginseng leaves,identified the components via gas chromatography-mass spectrometry(GC-MS),and then deciphered the mechanism of 2,3-Butanediol as the main component in the leachates responsible for resistance induction via RNA sequencing(RNA-seq).Prespraying leachates and 2,3-Butanediol onto leaves could induce the resistance of *** to Alternaria *** RNA-seq results showed that prespraying 2,3-Butanediol onto leaves with or without *** infection upregulated the expression of large number of genes,many of which are involved in transcription factor activity and the mitogen-activated protein kinase(MAPK) signaling ***,2,3-Butanediol spraying resulted in jasmonic acid(JA)-mediated induced systemic resistance(ISR) by activating MYC2 and ***,2,3-Butanediol induced systemic acquired resistance(SAR) by upregulating pattern-triggered immunity(PTI)-and effector-triggered immunity(ETI)-related genes and activated camalexin biosynthesis through activation of ***,2,3-Butanediol from the leachates of pine needles could activate the resistance of *** to leaf disease infection through ISR,SAR and camalexin ***,2,3-Butanediol is worth developing as a chemical inducer for agricultural production.

关键词： Pinus armandii Allelopathy Herbs Induce resistance Diversity Leaf disease

Sodium-dependent glucose transporter 2 inhibitors improve heart function in patients with type 2 diabetes and heart failure

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World Journal of Cardiology 2025年第1期17卷 110-117页

作者： yi-Fei Zhang Yu-xiang liu Wu-Xiao Yang Department of Cardiology Shanxi Provincial People's HospitalShanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina Department of Nephrology Shanxi Provincial People's HospitalShanxi Medical UniversityTaiyuan 030012Shanxi ProvinceChina

This article discusses the study by GrubićRotkvićet al on the mechanisms of action of sodium-glucose cotransporter 2 inhibitors(SGLT2i)in patients with type 2 diabetes mellitus(T2DM)and heart failure(HF).T2DM and HF are highly comorbid,with a significantly increased prevalence of HF in patients with ***2i exhibit potential in reducing hospitalization rates for HF and cardiovascular mortality through multiple mechanisms,including improving blood glucose control,promoting urinary sodium excretion,reducing sympathetic nervous system activity,lowering both preload and afterload on the heart,alleviating inflammation and oxidative stress,enhancing endothelial function,improving myocardial energy metabolism,and stabilizing cardiac ion *** research and clinical practice will help optimize the use of SGLT2i in HF patients.

关键词： Sodium-glucose cotransporter 2 inhibitors Type 2 diabetes mellitus Heart failure Diabetic cardiomyopathy Cardiovascular disease

Isolation and Identification of Flavone Type of Two Compounds from Salix matsudana

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Chemical Research in Chinese Universities 1998年第2期14卷 110-112页

作者： liu Moxiang, ZHENG yinan, liu Xiaofeng, LI xianggao and xiang Lan(Colle. of Chin. Midi. Material, Jilin Agricultural University, Changchun, 130118)

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关键词： Salix matsudana flavone Column chromatography Isolation and identification

Enhancement of bending toughness for Fe-based amorphous nanocrystalline alloy with deep cryogenic-cycling treatment

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China Foundry 2025年第1期22卷 99-107页

作者： yi-ran Zhang Dong Yang Qing-chun xiang Hong-yu liu Jing Pang ying-lei Ren Xiao-yu Li Ke-qiang Qiu School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Qingdao Yunlu Advanced Material Technology Co. Ltd.Qingdao 266232ShandongChina

The effects of deep cryogenic-cycling treatment(DCT)on the mechanical properties,soft magnetic properties,and atomic scale structure of the Fe_(73.5)Si_(13.5)B_(9)Nb_(3)Cu_(1)amorphous nanocrystalline alloy were *** DCT samples were obtained by subjecting the as-annealed samples to a thermal cycling process between the temperature of the supercooled liquid zone and the temperature of liquid *** flat plate bending testing,hardness measurements,and nanoindentation experiment,it is found that the bending toughness of the DCT samples is improved and the soft magnetic properties are also slightly *** are attributed to the rejuvenation behavior of the DCT samples,which demonstrate a higher enthalpy of ***,DCT is an effective method to enhance the bending toughness of Fe-based amorphous nanocrystalline alloys without degrading the soft magnetic properties.

关键词： deep cryogenic-cycling treatment Fe-based amorphous nanocrystalline alloy bending toughness rejuvenation