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Science China Chemistry 2024年第11期67卷 3791-3797页

作者： Debasis Pal Kirana D.Veeranna Yuk Fai Wong P.Andrew evans Department of Chemistry Queen's University Xiangya School of Pharmaceutical Sciences Central South University

The Reformatsky reagent derived from ethyl bromoacetate circumvents the challenge associated with the direct regio-and enantioselective iridium-catalyzed allylic alkylation with an unstabilized aliphatic ester enolate. Notably, this work represents the first example of using a Reformatsky reagent in a metal-allyl reaction, which permits the direct construction of enantioenriched β-stereogenic homoallylic esters without preactivation of the pronucleophile or post-reaction modification of the product(e.g., thermal decarboxylation of a 1,3-dicarbonyl). Moreover, the process allows the coupling of a broad range of sterically and electronically diverse electrophiles bearing aryl, heteroaryl and alkenyl derivatives, including the significantly more challenging alkyl-substituted allylic carbonates. The versatility of the ester product is exemplified by a series of functional group manipulations and the development of a concise and efficient enantioselective total synthesis of the natural product,(+)-descurainolide A. Finally, mechanistic studies indicate that the zinc enolate behaves as a soft nucleophile that undergoes outer-sphere alkylation.

关键词： allylic substitution asymmetric catalysis mechanistic studies natural product synthesis Reformatsky reagent

Functionalized selenium nanoparticles ameliorated acetaminophen-induced hepatotoxicity through synergistically triggering PKCδ/Nrf2 signaling pathway and inhibiting CYP 2e1

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Food Science and Human Wellness 2024年第2期13卷 932-945页

作者： Si Zou Yetao Gong Xiujie Li Yanbin Wu Jinzhong Wu Jianguo Wu ka-Hing Wong College of Pharmacy Fujian University of Traditional Chinese MedicineFuzhou 350122China Research Institute for Future Food The Hong Kong Polytechnic UniversityHong Kong 999077China Department of Food Science and Nutrition The Hong Kong Polytechnic UniversityHong Kong 999077China

Selenium nanoparticles(SeNPs)have been demonstrated potential for use in diseases associated with oxidative *** SeNPs with lower toxicity and higher biocompatibility could bring better therapeutic activity and clinical application ***,this work was conducted to investigate the protective effect of Pleurotus tuber-regium polysaccharide-protein complex funtionnalized SeNPs(PTR-SeNPs)against acetaminophen(APAP)-induced oxidative injure in HepG2 cells and C57BL/6J mouse *** elucidation of the underlying molecular mechanism,in particular their modulation of Nrf2 signaling pathway was also *** results showed that PTR-SeNPs could significantly ameliorate APAP-induced oxidative injury as evidenced by a range of biochemical analysis,histopathological examination and immunoblotting ***-SeNPs could hosphorylate and activate PKCδ,depress Keap1,and increase nuclear accumulation of Nrf2,resulting in upregulation of GCLC,GCLM,HO-1 and NQO-1 ***,PTR-SeNPs suppressed the biotransformation of APAP to generate intracellular ROS through CYP 2e1 inhibition,restoring the mitochondrial ***,the protective effect of PTR-SeNPs against APAP induced hepatotoxicity was weakened as Nrf2 was depleted in vivo,indicating the pivotal role of Nrf2 signaling pathway in PTR-SeNPs mediated hepatoprotective *** a potential hepatic protectant,PTR-SeNPs could serve as a new source of selenium supplement for health-promoting and biomedical applications.

关键词： PTR-SeNPs(polysaccharide-proteincomplex functionalized selenium nanoparticles) Acetaminophen-induced hepatotoxicity Nuclear factor erythroid 2-related factor 2 Cytochrome P450 enzyme 2e1 Mitochondria

Hyper spectral resolution stimulated Raman spectroscopy with amplified fs pulse bursts

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Light(Science & Applications) 2024年第3期13卷 566-576页

作者： Hongtao Hu Tobias Flöry Vinzenz Stummer Audrius Pugzlys Markus Zeiler Xinhua Xie Aleksei Zheltikov Andrius Baltuška Photonics Institute Technische Universität WienGußhausstraße 27-29Vienna A-1040Austria SwissFeL Paul Scherrer InstituteVilligen PSI 5232Switzerland Institute for Quantum Science and engineering Department of Physics and AstronomyTexas A&M UniversityCollege StationTX 77843USA

We present a novel approach for Stimulated Raman Scattering(SRS)spectroscopy in which a hyper spectral resolution and high-speed spectral acquisition are achieved by employing amplified offset-phase controlled fs-pulse *** investigate the method by solving the coupled non-linear Schrödinger equations and validate it by numerically characterizing SRS in molecular nitrogen as a model *** spectral resolution of the method is found to be determined by the inverse product of the number of pulses in the burst and the intraburst pulse *** SRS spectrum is obtained through a motion-free scanning of the offset phase that results in a sweep of the Raman-shift *** to high spectral resolution and fast motion-free scanning the technique is beneficial for a number SRS-based applications such as gas sensing and chemical analysis.

关键词： compound spectral resolution

Oxidative stress mediates glycidol-induced endothelial injury and its protection by 6-C-(e-2-fluorostyryl)naringenin

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Food Science and Human Wellness 2024年第5期13卷 2584-2594页

作者： Yue Zhou Hui Xu ka-Wing Cheng Feng Chen Qian Zhou Mingfu Wang College of Civil and Transportation engineering/College of Chemistry and environmental engineering Shenzhen UniversityShenzhen 518060China

Glycidol is a common lipid-derived foodborne toxicant mainly presents in refined oils and related *** endothelial cells may be potential targets of the deleterious effects associated with glycidol *** human umbilical vein endothelial cells(HUVeCs),we found that glycidol treatment promoted endothelialto-mesenchymal transition(endMT)at a lower concentration(0.5 mmol/L),while induced apoptosis and inflammation at a higher concentration(1 mmol/L).These harmful effects were achieved by the activation of NF-κB/MAPK signaling pathway and were mediated by reactive oxygen species(ROS).In addition,the protective potential of 6-C-(e-2-fluorostyryl)naringenin(6-CeFN)against glycidol was evaluated and compared with *** pre-treated with 6-CeFN,but not naringenin,displayed resistance to endothelial dysfunction caused by glycidol.

关键词： Glycidol endothelial cells 6-C-(e-2-fluorostyryl)naringenin Oxidative stress endothelial-to-mesenchymal transition

efficacy of nonsolvent flower pollen extracts in healthy women with urinary incontinence:A randomized,double-blind,placebo-controlled,parallel study

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Current Urology 2024年第3期18卷 203-211页

作者： Marc Moulin erin D.Lewis David C.Crowley Colleen e.May Malkanthi evans KGK Science Inc. LondonOntarioCanada Graminex L.L.C.SaginawMIUSA

Background Urinary incontinence(UI)is a debilitating and common condition that adversely affects quality of *** and surgical approaches for managing UI symptoms may result in undesirable risks and *** randomized,double-blind,placebo-controlled,parallel study investigated the efficacy of 2 nonsolvent flower pollen extracts on UI in healthy *** and methods One-hundred and fourteen women aged 40–75 years who scored≥5 on the International Consultation on Incontinence Questionnaire-Urinary Incontinence Short Form(ICIQ-SF)were randomized to receive either Graminex®RCT Fem™UI,Graminex®PollenBerry®,or placebo for 24 *** primary outcome was the change in the ICIQ-SF score between the trial and placebo groups after 24 weeks of *** secondary outcomes included changes in the frequency of nocturia(recorded in 3-day void diaries)and 24-hour leaka.e volume(assessed via pad weight)after 6,12,18,and 24 weeks of supplementation and changes in stress-induced urinary leaka.e volume(after completion of a provocative maneuver challenge)after 24 weeks of *** All the groups demonstrated improvement in ICIQ-SF scores at week 24(pe RCT Fem™UI group had the greatest improvement in ICIQ-SF scores(−4.07±3.4),followed by the PollenBerry®group(−3.34±2.87)and placebo group(−2.61±3.52).The RCT Fem™UI group had corresponding improvements in 24-hour leaka.e volume(−17.68±39.84 g)and frequency of nocturia(−0.52±1.26)(p≤0.05).PollenBerry®supplementation significantly improved stress-induced urinary leaka.e volume(−7.12±15.64 g)at week *** study products demonstrated safe hematological and chemical *** RCT Fem™UI supplementation resulted in significant and clinically meaningful reductions in UI severity,with corresponding improvements in daily urinary leaka.e volume and frequency of ***®significantly improved stress-induced urinary leaka.e volume,suggesting that it may be eff

关键词： Urinary incontinence Pollen extract Healthy women Dietary supplement ICIQ-SF Urinary leaka.e

The Dental Absces: epidemiological, Clinical and Therapeutic Aspects at the Dental Office of the Prefectoral Hospital of Siguiri in 2021 in the Republic of Guinea

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Open Journal of Stomatology 2024年第9期14卷 382-391页

作者： Magna Condé Aly Badara Nabé Fanta Madi Traoré Moussa Doré Djibrila Camara kaïn Condé Mory Sacko Francine Manto Kuete Kouamé Patrice Attogbain African Center of excellence for the Prevention and Control of Communicable Diseases (CeA-PCMT) Faculty of Health Sciences and Techniques of the Gamal Abdel Nasser University of Conakry Conakry Guinea Department of Odontology Faculty of Health Sciences and Techniques Gamal Abdel Nasser University of Conakry Conakry Guinea Department of Odontology and Maxillofacial Surgery of the Ignace Deen National Hospital Conakry Guinea Department of Pathology and Therapeutics UFR Odonto-Stomatology Felix Houphouet Boigny University Abidjan Ivory Coast

Introduction: A dental abscess is a collection of pus located in the tissues surrounding the tooth roots. The aim of this work is to describe the epidemiological, clinical and therapeutic aspects of dental abscess in order to contribute to the management of patients suffering from this pathology at the dental office of the Siguiri Prefectural Hospital. Methods: This was a retrospective descriptive study lasting 2 months carried out on the registers of patients received between October 2017 and October 2020 at the dental office of the Siguiri prefectural hospital. Results: 4690 patient files were identified during the study, of which 546 met our selection criteria, i.e. a frequency of 11.64%. During our study, we found 51.83% female compared to 48.17% male, i.e. a sex ratio of 1.07. 54.21% of our patients resided in rural communes compared to 45.76% for the urban commune. The age group most affected was that of 16 - 25 years old or 33.69%. Swelling, pain and functional discomfort were the reasons for consultation in all patients followed by other associated reasons in 41.21%. The premolar-molar group was the most represented, i.e. 86.70%. 80.04% of our patients presented an acute abscess compared to 19.96% of chronic cases. Antibiotic, analgesic, and mouthwash were prescribed in all patients during the study followed by 96.37% of cases prescription of steroidal anti-inflammatory drugs. 93.04% of causal teeth were extracted followed by 6.78% of cases of conservative treatment in our study. In our study, 80.95% of our patients had a good post-therapeutic outcome. Conclusion: This study highlights the need for prevention and early management of dental abscesses.

关键词： Dental Abscess epidemiological Clinical Therapeutic

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三轴加载下灰岩的力学特性及声发射特征

矿业研究与开发 2024年第2期44卷 129-137页

作者：王巍浩杜西岗许城高凯河北水利电力学院交通工程系河北沧州市061001 中冶(上海)钢结构科技有限公司上海201908 中绎建设科技集团有限公司河北石家庄050035

灰岩作为煤矿广泛赋存的沉积岩之一,揭示其力学性质和损伤演化过程对于煤炭资源的安全开采至关重要。针对取自淮北某矿81采区-950 m回风石门底板的灰岩试样进行了不同围压下的三轴压缩试验,并采用声发射对灰岩的变形破坏全过程进行监测... 详细信息

灰岩作为煤矿广泛赋存的沉积岩之一,揭示其力学性质和损伤演化过程对于煤炭资源的安全开采至关重要。针对取自淮北某矿81采区-950 m回风石门底板的灰岩试样进行了不同围压下的三轴压缩试验,并采用声发射对灰岩的变形破坏全过程进行监测。试验结果表明:(1)灰岩的应力-应变曲线可划分为四个阶段。随着围压的增大,弹性模量e、泊松比μ、起裂应力σ_(ci)以及峰值应力σ_(pv)均会增大,但闭合应力σ_(c)基本保持不变;应力比σ_(c)/σ_(pv)随围压的增大而减小,σ_(ci)/σ_(pv)与σ_(r)/σ_(pv)对围压变化不敏感,残余应力σ_(r)处的内聚力和内摩擦角相比于峰值应力处分别降低了18.94%和26.27%。(2)声发射(Ae)演化能够较好地表征灰岩的渐进性破坏过程,不同围压下灰岩的声发射演化规律保持一致;振铃计数峰值随着围压的增大而减小,声发射幅值均分布在20~100 dB范围内,灰岩试样内的高幅值Ae事件会随着轴向应力的加载增多并呈聚集分布。(3)以累计振铃计数作为特征参量建立的损伤演化模型能够较好地描述三轴应力下灰岩内部的微裂隙闭合、扩展、贯通直至发生宏观破坏这一渐进性破坏过程。

关键词：灰岩三轴压缩力学性质声发射损伤演化

Introducing Considerations in the Translation of Chinese Medicine

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Journal of Integrative Medicine 2014年第4期12卷 394-396页

作者： Sonya e.Pritzker ka-Kit Hui UCLA David Geffen School of Medicine Center for East-West Medicine

This article introduces the document, Considerations in the Translation of Chinese Medicine, published in PDF form online in both Chinese and english. This 20-page document includes several sections describing why the Considerations is necessary, the specificity of texts in Chinese medicine; the history of translation in Chinese medicine; who constitutes an ideal translator of Chinese medicine; what types of language exist in Chinese medicine; and specific issues in the translation of Chinese medicine, such as domestication versus foreignization, technical terminology, period-specific language, style, polysemy, and etymological translation. The final section offers a brief advisory for consumers, and concludes with a call to further discussion, and action, specifically in the development of international collaborative efforts towards the creation of more rigorous guidelines for the translation of Chinese medicine. The current article provides an overview of several of these sections, and includes links to the original document.

关键词： translation english Chinese medicine language

Building an e-Portfolio with a learning plan centric approach

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Journal of Zhejiang University-Science C(Computers and electronics) 2012年第1期13卷 37-47页

作者： Lam-for KWOK ka-shing CHAN Department of Computer Science City University of Hong Kong

A portfolio records achievements in the personal growth process. A personal development e-Portfolio assists an individual in planning his/her development path and reflecting upon his/her own learning. In this article, we propose an approach to constructing a personal development portfolio. An abstract information model is presented to support such a portfolio. The information model is proposed based upon and according to IMS standards. The use of this approach is illustrated by way of a prototype e-Portfolio system. The usage scenario and limitations of such a portfolio are also discussed.

关键词： e-Portfolio educational technology system Lifelong learning

Child-Pugh-Turcott versus Meld score for predicting survival in a retrospective cohort of black African cirrhotic patients

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World Journal of Gastroenterology 2008年第2期14卷 286-291页

作者： ka Attia KC Ackoundou-N'guessan AT N’dri-yoman AK Mahassadi e Messou YF Bathaix YH Kissi Service of Hepatology Gastroenterology and Generalmedicine Yopougon Teaching Hospital Abidjan Ivory Coast Service of Nephrology Dialysis andHypertension Yopougon Teaching Hospital Abidjan Ivory Coast Centre for the Management Research and Training onHIV/AIDS infection and related diseases (CEPREF-ACONDAVS) Yopougon-Attié Abidjan Ivory Coast

AIM: To compare the performance of the Child-Pugh-Turcott (CPT) score to that of the model for end-stage liver disease (MeLD) score in predicting survival of a retrospective cohort of 172 Black African patients with cirrhosis on a short and mid-term ***: Univariate and multivariate (Cox model) analyses were used to identify factors related to mortality. Relationship between the two scores was appreciated by calculating the correlation coefficient. The kaplan Meier method and the log rank test were used to elaborate and compare survival respectively. The Areas Under the Curves were used to compare the performance between scores at 3, 6 and 12 ***: The study population comprised 172 patients, of which 68.9% were male. The mean age of the patient was 47.5 ± 13 years. Hepatitis B virus infection was the cause of cirrhosis in 70% of the cases. The overall mortality was 31.4% over 11 years of follow up. Independent factors significantly associated with mortality were: CPT score (HR = 3.3, 95% CI [1.7-6.2]) (P e C vs stage A-B); Serum creatine (HR = 2.5, 95% CI [1.4-4.3]) (P = 0.001) (Serum creatine > 1.5 mg/dL versus serum creatine eLD score (HR = 2.9, 95% CI [1.63-5.21]) (P eLD > 21 vs MeLD e area under the curves (AUC) that predict survival was 0.72 and 0.75 at 3 mo (P = 0.68), 0.64 and 0.62 at 6 mo (P = 0.67), 0.69 and 0.64 at 12 mo (P = 0.38) respectively for the CPT score and the MeLD ***: The CPT score displays the sameprognostic significance as does the MeLD score in black African patients with cirrhosis. Moreover, its handling appears less cumbersome in clinical practice as compared to the latter.

关键词： Model for end-stage liver disease score Child score Cirrhosis Black African Survival