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Relationship between seminal plasma zinc concentration and spermatozoa-zona pellucida binding and the ZP-induced acrosome reaction in subfertile men

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Asian Journal of Andrology 2009年第4期11卷 499-507页

作者： De-Yi liu Boon-Shih Sie Ming-li liu franca Agresta HW Gordon Baker Department of Obstetrics and Gynaecology University of Melbourne Royal Women ＇s Hospital Parkville 3052 Australia Reproductive Services and Melbourne IVF Royal Women＇s Hospital Parkville 3052 Australia

The aim of this study was to determine the relationship between seminal zinc concentration and spermatozoazona pellucida （ZP） binding and the ZP-induced acrosome reaction （ZPIAR） in subfertile men. Semen analyses and seminal zinc concentration assessments were carried out according to the World Health Organization manual for 458 subfertile men. A spermatozoa-ZP interaction test was carried out by incubating 2 × 10^6 motile spermatozoa with a group of four unfertilized oocytes obtained from a clinical in vitro fertilization programme. After 2 h of incubation, the number of spermatozoa bound per ZP and the ZPIAR of ZP-bound spermatozoa were examined. The effect of adding 0.5 mmol L^-1 zinc to the media on the ZPIAR of spermatozoa from normozoospermic men was also tested in vitro. Seminal zinc concentration positively correlated with sperm count and duration of abstinence, but negatively correlated with semen volume. On analysis of data from all participants, both spermatozoa-ZP binding and the ZPI- AR were significantly correlated with sperm motility and normal morphology, but not with seminal zinc concentration. However, in men with normozoospermic semen, the seminal zinc concentration was significantly higher in men with defective ZPIAR （〈 16%） than in those with normal ZPIAR （ ≥ 16% ）（P 〈 0.01）. The addition of 0.5 mmol L^-1 zinc to the culture media had no effect on spermatozoa-ZP binding, but significantly reduced the ZPIAR in vitro （P 〈 0. 001）. In conclusion, seminal zinc concentration is correlated with sperm count and the duration of abstinence in subfertile men. In men with normozoospermic semen, high seminal zinc concentration may have an adverse effect on the ZPIAR.

关键词： semen analysis seminal zinc spermatozoa-zona pellucida interaction subfertile men

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Functional trait space and redundancy of plant communities decrease toward cold temperature at high altitudes in Southwest China

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Science China(life Sciences) 2023年第2期66卷 376-384页

作者： Lan Zhang Xiaojuan liu Zhenhua Sun Wensheng Bu franca J.Bongers Xiaoyang Song Jie Yang Zhenkai Sun Yin li Shan li Min Cao Keping Ma Nathan G.Swenson State Key Laboratory of Vegetation and Environmental Change Institute of BotanyChinese Academy of SciencesBeijing 100093China Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Key Laboratory of State Forestry Administration on Forest Ecosystem Protection and Restoration of Poyang Lake Watershed College of ForestryJiangxi Agricultural UniversityNanchang 330045China Key Laboratory of Tree Breeding and Cultivation Forestry and Grassland AdministrationResearch Institute of ForestryChinese Academy of ForestryBeijing 100091China Fujian Provincial Key Laboratory of Resources and Environmental Monitoring and Sustainable Management and Utilization Sanming UniversitySanming 365004China Department of Biological Sciences University of Notre DameNotre DameIndiana 46556USA

Plant communities in mountainous areas shift gradually as climatic conditions change with altitude. How trait structure in multivariate space adapts to these varying climates in natural forest stands is unclear. Studying the multivariate functional trait structure and redundancy of tree communities along altitude gradients is crucial to understanding how temperature change affects natural forest stands. In this study, the leaf area, specific leaf area, leaf carbon, nitrogen, and phosphorous content from 1,590 trees were collected and used to construct the functional trait space of 12 plant communities at altitudes ranging from 800 m to 3,800 m across three mountains. Hypervolume overlap was calculated to quantify species trait redundancy per community. First,hypervolumes of species exclusion and full species set were calculated, respectively. Second, the overlap between these two volumes was calculated to obtain hypervolume overlap. Results showed that the functional trait space significantly increased with mean annual temperature toward lower altitudes within and across three mountains, whereas species trait redundancy had different patterns between mountains. Thus, warming can widen functional trait space and alter the redundancy in plant communities. The inconsistent patterns of redundancy between mountains suggest that warming exerts varying influences on different ecosystems. Identification of climate-vulnerable ecosystems is important in the face of global warming.

关键词： leaf trait plant community hypervolume redundancy altitude natural forest

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Evolution of sequential bortezomib-dexamethasone treatment followed by autologous hematopoietic stem cell transplantation in hemodialysis treatment

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Chinese Medical Journal 2013年第9期126卷 1795-1795页

作者： li Cavoli Gioacchino Zagarrigo Carmela Servillo franca Coglitore Mario Schillaci Onofrio Tralongo Angelo Rotolo Ugo Nephrology and Dialysis Civic and Di Cristina Hospital Palermo Italy

T0 the editor： We read with interest the article of Zheng et al1 on sequential treatment with bortezomib plusdexamethasone followed by autologous hematopoietic stem cell transplantation （ASCT） in patients with mult...

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Effect of ions on the activity of brain acetylcholinesterase from tropical ifsh

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Journal of Coastal life Medicine 2015年第7期 505-514页

作者： Caio Rodrigo Dias Assis Amanda Guedes linhares Vagne Melo Oliveira Renata Cristina Penha franca Juliana Ferreira Santos Elba Verônica Matoso Maciel Carvalho Ranilson Souza Bezerra Luiz Bezerra Carvalho Jr Laboratory of Enzymology-LABENZ Biochemistry Department and Laboratory of Immunopathology Keizo AsamiFederal University of PernambucoRecife-PEBrazil Academic Unit of Serra Talhada Federal Rural University of PernambucoSerra Talhada-PEBrazil Laboratory of Glycoproteins Biochemistry DepartmentFederal University of PernambucoRecife-PEBrazil

Objective:To investigate the effect of ions on brain acetylcholinesterase(AChE;EC 3.***.1.7)activities from economic important fish[pirarucu,Arapaima gigas;tambaqui,Colossoma macropomum;cobia,Rachycentron canadum(***)and Nile tilapia,Oreochromis niloticus(***)]comparing with a commercial enzyme from electric eel[Electrophorus electricus(***)].Methods:Thein vitro exposure was performed at concentrations ranging from 0.001 to 10 mmol/L(except for ethylene diamine tetraacetic acid;up to 150 mmol/L).Inhibition kinetics *** *** were also observed through four methods(Michaelis-Menten,lineweaver-Burk,Dixon and Cornish-Bowden plots)in order to investigate the type of inhibition produced by some ***:Hg^(2+),As^(3+),Cu^(2+),Zn^(2+),Cd^(2+)caused inhibition in all the species under ***^(2+),Mg^(2+)and Mn^(2+)induced slight activation *** enzyme while Pb^(2+),Ba^(2+),Fe^(2+),li+inhibited the AChE from some of the analyzed *** lowest IC50 and Ki values were estimated *** AChE in presence of Hg^(2+),Pb^(2+),Zn^(2+).Under our experimental conditions,the results *** ***,As^(3+),Cu^(2+),Cd^(2+),Pb^(2+)and Zn^(2+)showed a non-competitive/mixed-type inhibition,while Hg^(2+)inhibited the enzyme in a mixed/competitive-like ***:*** AChE activity was affected by ten of fifteen ions under study showing that this enzyme could undergo interference by these ions when used as pesticide biosensor in environmental *** hindrance would be less relevant for the crude extracts.

关键词： Ions Acetylcholinesterase Biomarkers Fish

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The study of the influence of network resources on English Teaching under the background of informatization

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International Journal of Technology Management 2014年第1期 41-43页

作者： Shuping li Shandong Transport Vocational College WeifangShandong261206China

As an international language, English plays an extremely important role, and it has become the lingua franca of the world. For a long time, inefficiency exists in teaching or learning. Under the learning environment surrounded by native speakers, English, as a symbolic system, appears dull, or even because there is no information given appropriate experience and it becomes abstract. Many students are reluctant to learn after learning for a time, because it is difficult for reality, and it is not easy to consolidate, that 45 minutes of English learning environment also appears to be a little frustrated, as many students who have been admitted to the University said during the learning process of the entire university, they spent seventy percent of their energy to foreign language learning rather than their own major. This not only illustrates the importance of English teaching but also shows its difficult nature, the main reason is our bad English language teaching environment, there is a lack of communication in English language environment, however, the network information and the development of modern multimedia technology has greatly improve the English teaching environment. How to use the Internet information and multimedia technologies to create English learning environment, to optimize English teaching methods and to improve the quality of English teaching.

关键词： network resources English teaching informatization

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Researching and Teaching China and Hong Kong English

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基础教育外语教学研究 2015年第6期 56-61页

作者： David C. S. li

*** To put theory into practice-and let World Englishes (WE) and English as a lingua franca (ELF) insights inform local English curricula-much remains to be done,including basic research in local (ized) English features across all linguistic *** main challenge is intelligibility in international communication,currently the focus of intensive ELF ***,ownership and intelligibility are important issues that bear principally on social interaction,and so should receive more attention in the teaching of speaking and ***'needs that relate to reading and writing are rather different.

关键词：英语学习学习方法阅读知识阅读材料

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当代汉语文学话语生态分析初步

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陕西师范大学学报（哲学社会科学版） 2006年第2期35卷 81-87页

作者：李震陕西师范大学文学院陕西西安710062

认识并阐释文学作品的意义世界,乃至一个时代或一个地域的文学精神和文学论争,必须首先回到其赖以生长的话语生态中来。话语生态是适于某种文学话语生长的文化条件及其潜在的规定性。20世纪是汉语文学的话语生态从打破平衡走向新的平衡... 详细信息

认识并阐释文学作品的意义世界,乃至一个时代或一个地域的文学精神和文学论争,必须首先回到其赖以生长的话语生态中来。话语生态是适于某种文学话语生长的文化条件及其潜在的规定性。20世纪是汉语文学的话语生态从打破平衡走向新的平衡的特殊的文学史期。及至80年代以降,汉语文学的话语生态经过多半个世纪的碰撞、渗透与融合,形成了一个由古典语文、民间语文、公共话语和外来语等多种因素构成的复合形态,大大扩展了汉语文学的意义疆域。话语生态这一概念的提出,旨在提请当代汉语文学的写作、批评和研究者,回到当下的话语生态中来,将各种话语生态因素自觉转化成真正属于自己的个人话语,创造出属于我们这个时代的汉语文学。

关键词：当代汉语文学文学话语话语生态公共话语外来语个人话语文学作品

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乡村振兴背景下民族地区乡村国民语言能力提升和国家通用语能力建设——基于湘西土家族苗族自治州乡村语言调查

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西南民族大学学报（人文社会科学版） 2023年第3期44卷 160-168页

作者：李蔚武汉大学文学院武汉工商学院湖北武汉430072

乡村国民语言能力提升和国家通用语能力建设是民族地区实现巩固拓展脱贫攻坚成果同乡村振兴有效衔接的可持续发展路径。本文通过问卷调查、访谈以及观察等方法,对湘西土家族苗族自治州乡村居民语言生活状况进行考察。调查显示,当前乡村... 详细信息

乡村国民语言能力提升和国家通用语能力建设是民族地区实现巩固拓展脱贫攻坚成果同乡村振兴有效衔接的可持续发展路径。本文通过问卷调查、访谈以及观察等方法,对湘西土家族苗族自治州乡村居民语言生活状况进行考察。调查显示,当前乡村国民语言能力总体状况良好,推普工作成效显著,国家通用语在青壮年和学生群体中的普及率较高,“双言”现象普遍。研究进一步表明,国家通用语能力对个人以及经济社会发展具有正面效应;青壮年语言能力与受教育程度、择业、经济收入关联度较高。然而,当地仍存在一些与乡村经济社会发展不相适应的语言问题:州内语言呈碎片化;民族语衰微,呈老龄化态势;国家通用语普及存在不平衡现象,学生群体整体缺乏国家通用语普及对国民语言能力提升重要性认识等。本文建议以“通语”为核心任务,制定推普助力乡村振兴长效机制;重视以语言能力为基础的个人可持续发展能力的提升,扎实助推巩固拓展当地脱贫攻坚成果同乡村振兴有效衔接;注重以国家通用语为基础的多语能力的提高,为全面推进乡村振兴提供人才保障;加强地方语言文化科研投入力度,大力发展当地语言文化产业,助推民族地区乡村文化振兴。

关键词：乡村振兴民族地区国民语言能力国家通用语

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商务英语通用语语用能力探索

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外语学刊 2018年第6期 74-81页

作者：李清华李迪南方医科大学广州510515 广东外语外贸大学广州510420

本文在英语通用语（ELF）语用能力和商务英语通用语（BELF）能力理论的基础上。结合实证研究的成果。以“社会建构论”和“交叉文化语用观”为理论基础，提出商务英语通用语语用能力模式。BELF语用能力包括意义共建能力、身份共建能力... 详细信息

本文在英语通用语（ELF）语用能力和商务英语通用语（BELF）能力理论的基础上。结合实证研究的成果。以“社会建构论”和“交叉文化语用观”为理论基础，提出商务英语通用语语用能力模式。BELF语用能力包括意义共建能力、身份共建能力与礼貌共建能力。3者均表现为特定的语用策略，交际者基于个人的语用知识库（语用语言知识、社交语用知识和国际商务专业知识）选择和使用语用策略。我们认为，商务英语语用教学的主要内容是语用知识，但这些知识应融人到真实鲜活的课堂任务中，通过训练学生语用策略的灵活使用，帮助他们完成知识的内化。在商务英语语用能力测试中，意义共建能力、身份共建能力与礼貌共建能力是3个主要构念成分，应围绕这些构念设计测试任务和评分标准。

关键词：英语通用语商务英语通用语语用能力语用策略语用知识社会建构论

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论中国语言资源有声数据库的建设

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中国语文 2010年第4期 356-363页

作者：李宇明教育部语言文字信息管理司北京100010

中国语言资源有声数据库,是国家语委正在开展的一项语言工程,旨在用现代信息技术、遵循统一的工作规范和技术规范、将中国各县域的语言实态(也包括方言和地方普通话)记录下来,归档建库,永久保存。通过对该库的学术开发和行政开发,可以... 详细信息

中国语言资源有声数据库,是国家语委正在开展的一项语言工程,旨在用现代信息技术、遵循统一的工作规范和技术规范、将中国各县域的语言实态(也包括方言和地方普通话)记录下来,归档建库,永久保存。通过对该库的学术开发和行政开发,可以起到全面了解语言国情、科学制定国家语言规划、科学保存和开发国家语言资源、促进普通话的推广、促进语言文字的信息化、促进语言科学的发展等作用。

关键词：中国语言有声数据库

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