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地下水铀污染的原位微生物还原与固定:在美国能源部田纳西橡树岭放射物污染现场的试验 被引量:30
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作者 吴唯民 Jack Carley +19 位作者 David Watson 顾宝华 Scott brooks Shelly D.Kelly Kenneth Kemner Joy D.van Nostrand 吴力游 许玫英 周集中 罗剑 Erick Cardenas 黄家琪 Matthew W.Fields Terence L.Marsh James M.Tiedje Stefan J.Green Joel E.Kostka Peter K.Kitanidis Philip M.Jardme CraigS.Criddle 《环境科学学报》 CAS CSCD 北大核心 2011年第3期449-459,共11页
总结了美国斯坦福大学和橡树岭国家实验室等在美国能源部田纳西州橡树岭综合试验基地进行的铀污染原位微生物修复阶段性试验结果.本试验利用微生物以乙醇为电子供体还原地下水和沉积物中的六价铀为不溶解的四价铀,使之原位固定化.随后... 总结了美国斯坦福大学和橡树岭国家实验室等在美国能源部田纳西州橡树岭综合试验基地进行的铀污染原位微生物修复阶段性试验结果.本试验利用微生物以乙醇为电子供体还原地下水和沉积物中的六价铀为不溶解的四价铀,使之原位固定化.随后通过加入溶解氧和硝酸盐来试验微生物还原后的地下水层中还原固定态铀的稳定性.通过预处理和长期间隔注入乙醇溶液,地下水中铀浓度从40~60mg·L-1降至0.03mg·L-1以下,达到了美国环保署饮用水的标准.还原的四价铀主要以U(Ⅳ)-Fe复合物的形态存在.结果表明,固定化后的四价铀只有在厌氧条件下才是稳定的,溶解氧和硝酸盐侵入地下水层后会使固定化的四价铀重新氧化为溶解态的六价铀.在试验过程中,采用多种分子生物学方法检测了微生物种群的变化和与铀氧化还原反应有关的功能微生物.本研究表明,在维持试验系统无氧和无硝酸盐的条件下,通过添加乙醇为电子供体可有效地促进地下水中土著功能微生物的活性,从而实现铀的原位还原固定与稳定. 展开更多
关键词 铀污染 微生物还原 原位生物修复 地下水 沉积物
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A 1000-year chironomid-based salinity reconstruction from varved sediments of Sugan Lake,Qaidam Basin,arid Northwest China,and its palaeoclimatic significance 被引量:23
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作者 CHEN JianHui CHEN FaHu +3 位作者 ZHANG EnLou brooks Stephen J ZHOU AiFeng ZHANG JiaWu 《Chinese Science Bulletin》 SCIE EI CAS 2009年第20期3749-3759,共11页
A 1000-year high-resolution(~10 years) chironomid record from varved sediments of Sugan Lake,Qaidam Basin on the northern Tibetan Plateau,is presented.The chironomid assemblages are mainly composed of the relatively ... A 1000-year high-resolution(~10 years) chironomid record from varved sediments of Sugan Lake,Qaidam Basin on the northern Tibetan Plateau,is presented.The chironomid assemblages are mainly composed of the relatively high-saline-water taxa Psectrocladius barbimanus-type and Orthocladius/Cricotopus,and the relatively low-saline-water taxa Procladius and Psectrocladius sordidellus-type.Variations in the chironomid fauna and inferred salinities suggest that over the last millennium,the Sugan Lake catchment has alternated between contrasting climatic conditions,having a dry climate during the period 990―1550 AD,a relatively humid climate during the Little Ice Age(LIA)(1550―1840 AD),and a dry climate again from 1840 AD onwards.At the decadal to centennial scale,a wet event around 1200―1230 AD,interrupting the generally arid period(990―1550 AD),and a dry event around 1590―1700 AD,punctuating the generally humid period(1550―1840 AD),are clearly documented.Trends in the chironomid-based salinity time series indicate a highly unstable climate during the LIA when salinity fluctuations were of greater magnitude and higher frequency.The effective moisture evolution in the Sugan Lake catchment during the last millennium reconstructed by chironomid analysis is in broad agreement with previous palaeo-moisture data derived from other sites in arid Northwest China(ANC).The LIA,characterized by generally humid conditions over the west-erly-dominated ANC was distinctly different from that in monsoonal China,implying an "out-of-phase" relationship between moisture evolution in these two regions during the past 1000 years. 展开更多
关键词 西北干旱地区 柴达木盆地 古气候意义 沉积物 中国 盐度 纹层
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标准·方案·指南——2014年美国癌症学会最新宫颈癌筛查指南及筛查中存在的问题 被引量:16
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作者 Robert A Smith Deana Manassaram-Baptiste +6 位作者 Durado brooks Vilma Cokkinides Mary Doroshenk Debbie Saslow Richard C Wender Otis W Brawley 王静 《中国全科医学》 CAS CSCD 北大核心 2014年第27期3163-3164,共2页
美国癌症学会(ACS)每年都会发布有关癌症早期检测、癌症筛查率数据与趋势报告及相关问题的指南,并会持续关注可能需要在癌症筛查指南中做出相应改变与更新的医学科学文献中出现的新证据以及需要传达给临床工作者与公众的筛查相关信息。... 美国癌症学会(ACS)每年都会发布有关癌症早期检测、癌症筛查率数据与趋势报告及相关问题的指南,并会持续关注可能需要在癌症筛查指南中做出相应改变与更新的医学科学文献中出现的新证据以及需要传达给临床工作者与公众的筛查相关信息。在制定新指南的过程中,ACS至少每5年对指南更新1次,如有重要新证据出现,则更新间隔时间会更短。本期就2014年ACS关于宫颈癌筛查的最新指南报道如下。 展开更多
关键词 宫颈肿瘤 诊断检查服务 指南 乳头状瘤病毒感染 乳头状瘤病毒疫苗
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柴达木盆地苏干湖年纹层岩芯摇蚊记录的过去1000年干旱区湿度变化及其意义 被引量:13
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作者 陈建徽 陈发虎 +3 位作者 张恩楼 Stephen J brooks 周爱锋 张家武 《科学通报》 EI CAS CSCD 北大核心 2009年第20期3127-3135,共9页
利用柴达木盆地苏干湖具有年纹层的沉积岩芯,以摇蚊亚化石分析恢复了研究区近千年来10年分辨率的湿度演变历史.研究表明,苏干湖岩芯中的摇蚊亚化石主要由高咸水属种Psectrocladius barbimanus-type和Orthocladius/Cricotopus与低咸水属... 利用柴达木盆地苏干湖具有年纹层的沉积岩芯,以摇蚊亚化石分析恢复了研究区近千年来10年分辨率的湿度演变历史.研究表明,苏干湖岩芯中的摇蚊亚化石主要由高咸水属种Psectrocladius barbimanus-type和Orthocladius/Cricotopus与低咸水属种Procladius和Psectrocladius sordidellus-type组成,依据其相对丰度的变化,结合摇蚊-盐度转换函数重建的盐度波动,区域过去1000年湿度变化可划分为3个阶段:990~1550AD为气候整体干旱期、1550~1840AD为气候整体湿润期、1840~2000AD为全球变暖下的气候再次干旱期.高分辨率的记录还发现,在年代际到百年尺度上,存在1200~1230AD干旱背景下的湿润阶段和1590~1700AD湿润小冰期内部的干旱阶段;就气候变率而言,湿润小冰期时段摇蚊种群组合及重建的盐度变化幅度增大,频率加快,指示出小冰期气候的不稳定性特征.该记录得到西风环流影响区的其他古湿度资料支持.苏干湖高分辨率摇蚊记录的湿润小冰期气候与中国东部季风区降水变化存在明显的差异,表明中国内陆干旱区和东部季风区湿度变化即使在近1000年来也存在相位差. 展开更多
关键词 苏干湖 内陆干旱区 摇蚊亚化石 有效湿度 过去1000年
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The amazing potential of fungi:50 ways we can exploit fungi industrially 被引量:12
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作者 Kevin D.Hyde Jianchu Xu +60 位作者 Sylvie Rapior Rajesh Jeewon Saisamorn Lumyong Allen Grace T.Niego Pranami D.Abeywickrama Janith V.S.Aluthmuhandiram Rashika S.Brahamanage Siraprapa brooks Amornrat Chaiyasen K.W.Thilini Chethana Putarak Chomnunti Clara Chepkirui Boontiya Chuankid Nimali I.de Silva Mingkwan Doilom Craig Faulds Eleni Gentekaki Venkat Gopalan Pattana Kakumyan Dulanjalee Harishchandra Hridya Hemachandran Sinang Hongsanan Anuruddha Karunarathna Samantha C.Karunarathna Sehroon Khan Jaturong Kumla Ruvishika S.Jayawardena Jian-Kui Liu Ningguo Liu Thatsanee Luangharn Allan Patrick G.Macabeo Diana S.Marasinghe Dan Meeks Peter E.Mortimer Peter Mueller Sadia Nadir Karaba N.Nataraja Sureeporn Nontachaiyapoom Meghan O’Brien Watsana Penkhrue Chayanard Phukhamsakda Uma Shaanker Ramanan Achala R.Rathnayaka Resurreccion B.Sadaba Birthe Sandargo Binu C.Samarakoon Danushka S.Tennakoon Ramamoorthy Siva Wasan Sriprom T.S.Suryanarayanan Kanaporn Sujarit Nakarin Suwannarach Thitipone Suwunwong Benjarong Thongbai Naritsada Thongklang Deping Wei S.Nuwanthika Wijesinghe Jake Winiski Jiye Yan Erandi Yasanthika Marc Stadler 《Fungal Diversity》 SCIE 2019年第4期1-136,共136页
Fungi are an understudied,biotechnologically valuable group of organisms.Due to the immense range of habitats that fungi inhabit,and the consequent need to compete against a diverse array of other fungi,bacteria,and a... Fungi are an understudied,biotechnologically valuable group of organisms.Due to the immense range of habitats that fungi inhabit,and the consequent need to compete against a diverse array of other fungi,bacteria,and animals,fungi have developed numerous survival mechanisms.The unique attributes of fungi thus herald great promise for their application in biotechnology and industry.Moreover,fungi can be grown with relative ease,making production at scale viable.The search for fungal biodiversity,and the construction of a living fungi collection,both have incredible economic potential in locating organisms with novel industrial uses that will lead to novel products.This manuscript reviews fifty ways in which fungi can potentially be utilized as biotechnology.We provide notes and examples for each potential exploitation and give examples from our own work and the work of other notable researchers.We also provide a flow chart that can be used to convince funding bodies of the importance of fungi for biotechnological research and as potential products.Fungi have provided the world with penicillin,lovastatin,and other globally significant medicines,and they remain an untapped resource with enormous industrial potential. 展开更多
关键词 BIOCONTROL Biodiversity BIOTECHNOLOGY Food FUNGI MUSHROOMS
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New insights into p53 activation 被引量:9
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作者 Christopher L brooks Wei Gu 《Cell Research》 SCIE CAS CSCD 2010年第6期614-621,共8页
The tumor suppressor p53 is a multifunctional, highly regulated, and promoter-specific transcriptional factor that is uniquely sensitive to DNA damage and cellular stress signaling. The mechanisms by which p53 directs... The tumor suppressor p53 is a multifunctional, highly regulated, and promoter-specific transcriptional factor that is uniquely sensitive to DNA damage and cellular stress signaling. The mechanisms by which p53 directs a damaged cell down either a cell growth arrest or an apoptotic pathway remain poorly understood. Evidence suggests that the in vivo functions of p53 seem to balance the cell-fate choice with the type and severity of damage that occurs. The concept of antirepression, or inhibition of factors that normally keep p53 at bay, may help explain the physiological mechanisms for p53 activation. These factors also provide novel chemotherapeutic targets for the reactivation of p53 in tumors harboring a wild-type copy of the gene. 展开更多
关键词 MDM2 antirepression DESTABILIZATION UBIQUITINATION transcriptional activation and stability
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The tortuous path of lactate shuttle discovery:From cinders and boards to the lab and ICU 被引量:8
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作者 George A.brooks 《Journal of Sport and Health Science》 SCIE 2020年第5期446-460,共15页
Once thought to be a waste product of oxygen limited(anaerobic)metabolism,lactate is now known to form continuously under fully oxygenated(aerobic)conditions.Lactate shuttling between producer(driver)and consumer cell... Once thought to be a waste product of oxygen limited(anaerobic)metabolism,lactate is now known to form continuously under fully oxygenated(aerobic)conditions.Lactate shuttling between producer(driver)and consumer cells fulfills at least 3 purposes;lactate is:(1)a major energy source,(2)the major gluconeogenic precursor,and(3)a signaling molecule.The Lactate Shuttle theory is applicable to diverse fields such as sports nutrition and hydration,resuscitation from acidosis and Dengue,treatment of traumatic brain injury,maintenance of glycemia,reduction of inflammation,cardiac support in heart failure and following a myocardial infarction,and to improve cognition.Yet,dysregulated lactate shuttling disrupts metabolic flexibility,and worse,supports oncogenesis.Lactate production in cancer(the Warburg effect)is involved in all main sequela for carcinogenesis:angiogenesis,immune escape,cell migration,metastasis,and self-sufficient metabolism.The history of the tortuous path of discovery in lactate metabolism and shuttling was discussed in the 2019 American College of Sports Medicine Joseph B.Wolffe Lecture in Orlando,FL. 展开更多
关键词 Anaerobic metabolism EXERCISE GLYCOLYSIS Oxidative metabolism Warburg Effect
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Bak在细胞凋亡期间对线粒体形态学的影响 被引量:5
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作者 冯乐平 乔伟 +1 位作者 Craig brooks Zeng Dong 《吉林大学学报(医学版)》 CAS CSCD 北大核心 2008年第5期773-777,F0002,共6页
目的:探讨Bak基因在细胞凋亡线粒体信号传导中的作用以及与Bax基因之间的相互关系。方法:应用Bax/Bak双重基因敲除的小鼠胚胎成纤维细胞(MEF)和Hela细胞进行基因重构,细胞按不同基因型(野生型、Bax敲除和Bak敲除、双重基因敲除)分组,并... 目的:探讨Bak基因在细胞凋亡线粒体信号传导中的作用以及与Bax基因之间的相互关系。方法:应用Bax/Bak双重基因敲除的小鼠胚胎成纤维细胞(MEF)和Hela细胞进行基因重构,细胞按不同基因型(野生型、Bax敲除和Bak敲除、双重基因敲除)分组,并通过共转染方式导入目的基因。细胞凋亡的处理条件:细胞在无葡萄糖缓冲液的培养基中,在含10mmol.L-1叠氮钠或1μmol.L-1十字孢碱(STS)或20μmol.L-1顺铂条件下培养,并诱导细胞凋亡。应用共聚焦显微镜和免疫荧光及免疫印记技术分析细胞凋亡、线粒体碎裂和细胞色素C释放情况,综合评价Bak基因在细胞凋亡和线粒体碎裂中的作用。结果:Hela细胞内线粒体碎裂和细胞色素C释放百分率分别与细胞凋亡有关联(P<0.01);MEF细胞在Bak基因缺失(Bak-/-)时,应用化学诱导剂导致的细胞凋亡率(17.9%)明显低于野生型MEF细胞(71.3%)(P<0.01);且Bax和Bak基因两者协同作用可以增强细胞凋亡发生率;当pEGFP-Bak重新导入Bax-/-/Bak-/-MEF细胞,线粒体破碎百分率从43.7%增加到76.4%,pEGFP-Bak组细胞凋亡率明显高于pEGFP-Bax组(P<0.05);应用不同的化学诱导剂均可以得到同样的结果;且Bcl-2不能够明显阻止Bak诱导的细胞凋亡。结论:Bak基因明确诱导线粒体碎裂和细胞色素C释放,导致细胞凋亡,其诱导细胞凋亡的效果明显大于Bax基因,并且其作用独立于Bax基因功能之外。 展开更多
关键词 细胞凋亡 细胞色素C 线粒体 BAX基因 BAK基因
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中国劳动力市场:绩效及其挑战 被引量:3
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作者 Ray brooks 陶然 《世界经济文汇》 CSSCI 北大核心 2004年第1期4-23,共20页
在过去 2 0年中 ,伴随着城镇私营部门重要地位的不断彰显与国有企业规模的缩减 ,中国已经形成了一个市场化程度日渐提高的劳动力市场。尽管改革进程亦行亦渐 ,在农村和国有企业中依旧存在着大量的剩余劳动力。在未来的几年当中 ,中国劳... 在过去 2 0年中 ,伴随着城镇私营部门重要地位的不断彰显与国有企业规模的缩减 ,中国已经形成了一个市场化程度日渐提高的劳动力市场。尽管改革进程亦行亦渐 ,在农村和国有企业中依旧存在着大量的剩余劳动力。在未来的几年当中 ,中国劳动力市场所面对的首要挑战就是如何在应对入世冲击的同时 ,将剩余劳动力转移到有质量的岗位中去。据本文估计 ,如果中国的GDP年均增长率保持在 7%的水平而就业弹性为 0 .5 ,则接下来的 3至 4年内 ,城镇失业率将翻一番 ,达到 10 %左右。当然 ,强劲的经济增长有助于缓解这一压力。尤其值得重视的是 ,私营部门和近年来提供了众多就业岗位的劳动力密集型服务业的蓬勃发展极大促进了就业。因此 ,政府的政策实施重点应当包括鼓励私营部门发展、打破阻碍劳动力流动的壁垒、提升劳动者技能、改进职业介绍服务以及加强社会安全网等方面。 展开更多
关键词 劳动力市场 中国 剩余劳动力 就业弹性 失业率 就业岗位 改革 绩效评价
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Dynamic condylar screw or hip joint (spanning) external fixator for treatment of pathological fractures of femoral neck and trochanter secondary to benign lesions 被引量:6
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作者 ZHANG Chun-lin ZENG Bing-fang +2 位作者 DONG Yang Daria brooks Terrell Martin M. Malawer 《Chinese Medical Journal》 SCIE CAS CSCD 2008年第2期178-180,共3页
The treatment of pathological fractures of the femoral neck and trochanteric region secondary to benignlesions can be a challenge for orthopaedic surgeons because of the size and nature of the lesions, the resulting ... The treatment of pathological fractures of the femoral neck and trochanteric region secondary to benignlesions can be a challenge for orthopaedic surgeons because of the size and nature of the lesions, the resulting bony defect, the risk of recurrence, the possible associated deformities, and the risk of osteonecrosis. Numerous treatment modalities have been reported for the management of pathological fractures of the proximal femur secondary to benign lesions. An unsatisfactory outcome in 25% of patients and a complication rate of 45% have been observed. 展开更多
关键词 pathological fractures benign lesions dynamic condylar screw external fixator
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Conceptus elongation in ruminants: roles of progesterone, prostaglandin, interferon tau and cortisol 被引量:6
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作者 Kelsey brooks Greg Burns Thomas E Spencer 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2015年第2期151-162,共12页
The majority of pregnancy loss in ruminants occurs during the first three weeks after conception, particularly during the period of conceptus elongation that occurs prior to pregnancy recognition and implantation. Thi... The majority of pregnancy loss in ruminants occurs during the first three weeks after conception, particularly during the period of conceptus elongation that occurs prior to pregnancy recognition and implantation. This review integrates established and new information on the biological role of ovarian progesterone (P4), prostaglandins (PGs), interferon tau (IFNT) and cortisol in endometrial function and conceptus elongation. Progesterone is secreted by the ovarian corpus luteum (CL) and is the unequivocal hormone of pregnancy. Prostaglandins (PGs) and cortisol are produced by both the epithelial cells of the endometrium and the trophectoderm of the elongating conceptus. In contrast, IFNT is produced solely by the conceptus trophectoderm and is the maternal recognition of pregnancy signa that inhibits production of luteolytic pulses of PGF2α by the endometrium to maintain the CL and thus production of P4. Available results in sheep support the idea that the individual, interactive, and coordinated actions of P4, PGs, IFNT and cortisol regulate conceptus elongation and implantation by controlling expression of genes in the endometrium and/or trophectoderm. An increased knowledge of conceptus-endometrial interactions during early pregnancy in ruminants is necessary to understand and elucidate the causes of infertility and recurrent early pregnancy loss and provide new strategies to improve fertility and thus reproductive efficiency. 展开更多
关键词 CONCEPTUS CORTISOL ENDOMETRIUM INTERFERON Prostaqlandin RUMINANT
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人类T型钙通道α_(1H)亚单位基因在细胞增殖中的功能研究 被引量:4
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作者 王跃群 brooks Gavin +3 位作者 朱传柄 袁婺洲 李永青 吴秀山 《Acta Genetica Sinica》 SCIE CAS CSCD 北大核心 2002年第8期659-665,共7页
将人类T型钙通道α1H 亚单位基因 (CACNA1H)cDNA转染到HEK 2 93(humanembroyonickidney)细胞系得到稳定过量表达的细胞株 ,以此为体外模型来研究T型钙通道在细胞增殖中的直接作用。RT -PCR和标准全细胞膜片钳记录分别从mRNA转录水平和T... 将人类T型钙通道α1H 亚单位基因 (CACNA1H)cDNA转染到HEK 2 93(humanembroyonickidney)细胞系得到稳定过量表达的细胞株 ,以此为体外模型来研究T型钙通道在细胞增殖中的直接作用。RT -PCR和标准全细胞膜片钳记录分别从mRNA转录水平和T型钙通道蛋白功能水平验证了α1H 亚单位的过量表达。生长曲线结果表明 ,T型钙通道α1H 亚单位基因的过量表达能显著促进HEK - 2 93细胞增殖 ,将细胞群体倍增时间从对照细胞的 2 2 1± 1.1h缩短到稳定转染细胞的 14 0± 0 .4h ,细胞群体倍增时间缩短了约 8h ;流式细胞分析结果表明 ,在稳定转染细胞处于S期的细胞百分率比对照细胞高 ,相反地处于G1 期的百分率比对照细胞低 ,以上结果证明了过量表达T型钙通道亚单位α1H 基因能促进细胞增殖。Western印迹结果提示 ,T型钙通道α1H 亚单位基因表达产物是通过某种信号途径 ,提高了与细胞周期有关基因 (CDK2、cyclinA和cyclinE)的蛋白质表达水平 ,从而刺激了细胞周期的进程。 展开更多
关键词 人类 T型钙通道α1H亚单位基因 细胞增殖 功能 HEK-293细胞 机制 血管疾病
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Treating amyotrophic lateral sclerosis with allogeneic Schwann cell-derived exosomal vesicles: a case report
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作者 Pascal J.Goldschmidt-Clermont Aisha Khan +8 位作者 George Jimsheleishvili Patricia Graham Adriana brooks Risset Silvera Alexander J.P.Goldschmidt Damien D.Pearse W.Dalton Dietrich Allan D.Levi James D.Guest 《Neural Regeneration Research》 SCIE CAS 2025年第4期1207-1216,共10页
Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular junction.In amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann c... Schwann cells are essential for the maintenance and function of motor neurons,axonal networks,and the neuromuscular junction.In amyotrophic lateral sclerosis,where motor neuron function is progressively lost,Schwann cell function may also be impaired.Recently,important signaling and potential trophic activities of Schwann cell-derived exosomal vesicles have been reported.This case report describes the treatment of a patient with advanced amyotrophic lateral sclerosis using serial intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles,marking,to our knowledge,the first instance of such treatment.An 81-year-old male patient presented with a 1.5-year history of rapidly progressive amyotrophic lateral sclerosis.After initial diagnosis,the patient underwent a combination of generic riluzole,sodium phenylbutyrate for the treatment of amyotrophic lateral sclerosis,and taurursodiol.The patient volunteered to participate in an FDA-approved single-patient expanded access treatment and received weekly intravenous infusions of allogeneic Schwann cell-derived exosomal vesicles to potentially restore impaired Schwann cell and motor neuron function.We confirmed that cultured Schwann cells obtained from the amyotrophic lateral sclerosis patient via sural nerve biopsy appeared impaired(senescent)and that exposure of the patient’s Schwann cells to allogeneic Schwann cell-derived exosomal vesicles,cultured expanded from a cadaver donor improved their growth capacity in vitro.After a period of observation lasting 10 weeks,during which amyotrophic lateral sclerosis Functional Rating Scale-Revised and pulmonary function were regularly monitored,the patient received weekly consecutive infusions of 1.54×1012(×2),and then consecutive infusions of 7.5×1012(×6)allogeneic Schwann cell-derived exosomal vesicles diluted in 40 mL of Dulbecco’s phosphate-buffered saline.None of the infusions were associated with adverse events such as infusion reactions(allergic or otherwise)or changes in vital signs.Clinical lab ser 展开更多
关键词 ALLOGENEIC amyotrophic lateral sclerosis EXOSOMES INFUSION neuromuscular junction Schwann cell
基于长期研究队列的广西隆安县乙型肝炎病毒准种研究 被引量:2
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作者 贾蕙华 陈钦艳 +6 位作者 蒋智华 王学燕 张文嘉 TIM J Harrison J brooks Jackson LI Wu 方钟燎 《中国热带医学》 CAS 2023年第8期822-827,共6页
目的明确广西隆安县队列HBsAg无症状携带者感染的乙型肝炎病毒(hepatitis B virus,HBV)准种序列长期演化特征。方法收集9名广西隆安县队列HBsAg无症状携带者2004年、2007年、2013年、2019年或2020年4个不同时间点血清样本。酶联免疫吸... 目的明确广西隆安县队列HBsAg无症状携带者感染的乙型肝炎病毒(hepatitis B virus,HBV)准种序列长期演化特征。方法收集9名广西隆安县队列HBsAg无症状携带者2004年、2007年、2013年、2019年或2020年4个不同时间点血清样本。酶联免疫吸附测定法检测HBV血清学标志物;聚合酶链式反应(polymerase chain reaction,PCR)荧光探针法检测HBV病毒载量;试剂盒提取HBV DNA;PCR法扩增HBV全基因组,进行二代测序;利用Mega等软件对所获得的序列进行生物信息学分析。结果共获得23份血清样本,309条全长基因准种序列,每份标本平均获得(0.18±0.07)G测序数据量。55.55%(5/9)的研究对象携带的HBV毒株基因型在长期进化过程中发生了基因型转换,PreS/S区系统进化树基因分型结果与全基因组分析结果完全一致;发现B/C、I/C重组体;各研究标本的Sn值范围为0~0.37,D值范围为0~0.11;共检出21种特殊单核苷酸/氨基酸突变位点(S区7种,X区2种,PreC区3种,BCP区9种)和6种缺失突变,发现多联突变组合形式,未发现任何耐药突变,77.8%(7/9)研究对象在2004年携带的HBV毒株发生了BCP区nt1762(A→T)/1764(G→A)双突变和PreC区1896位(G→A)点突变,HBV基因可在无抗病毒药物压力下由突变型可恢复为野生型和(或)野生型转变为突变型;HBV基因组进化率为2.03×10^(-5)~3.50×10^(-3)。结论在HBV自然感染进程中,HBV基因型和重组体、准种复杂性和多样性可随时间发生改变;HBV基因突变型和野生型可相互转换,一定程度上降低了利用基因型和相关突变来预测临床结局的价值;隆安县乙型肝炎表面抗原(hepatitis B surface antigen,HBsAg)无症状携带者HBV基因组进化率很高。 展开更多
关键词 乙型肝炎病毒 基因型 二代测序 准种 基因突变
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Modulation of antioxidant status in streptozotocin-induced diabetic male wistar rats following intake of red palm oil and/or rooibos 被引量:5
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作者 Ademola Ayeleso Nicole brooks Oluwafemi Oguntibeju 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2014年第7期536-544,共9页
Objective:To investigate the role of red palm oil(RPO),rooibos tea extract(RTE)and their combined treatment(RPO+RTE)on antioxidant status in streptozotocin(STZ)-induced diabetic rats.Methods:Diabetes mellitus was indu... Objective:To investigate the role of red palm oil(RPO),rooibos tea extract(RTE)and their combined treatment(RPO+RTE)on antioxidant status in streptozotocin(STZ)-induced diabetic rats.Methods:Diabetes mellitus was induced by a single administration of streptozotocin(50 mg/kg)and the rats were treated for 7 weeks.Antioxidant enzymes[calalase(CAT),glutathione peroxidase(GPx),superoxide dismutase(SOD)],antioxidant capacity[trolox equivalence antioxidant capacity(TEAC),oxygen radical absorbance capacity(ORAC)]as well as total protein,albumin,globulin,total glutathione,conjugated diene and thiobarbituric acid reactive substances(TBARS)were investigated.Results:Treatment with RPO,RTE and RPO+RTE significantly(p>0.05)improved liver SOD and plasma ORAC in the diabetic rats.Similarly,diabetic rats treated with RTE and RPO+RTE enhanced liver GPx.A significant(P<0.05)increase in the plasma TBARS in the diabetic control group was observed when compared with the normal control group.Treatment of diabetic rats with RTE and RPO+RTE reduced plasma TBARS to a level not significantly different at P<0.05 from the normal control group.Conclusions:The results revealed the anti-oxidative potentials of red palm oil,rooibos and their combination in diabetic conditions and hence,they could be useful in the management of diabetes and its complications. 展开更多
关键词 Red PALM oil Rooibos ANTIOXIDANT STREPTOZOTOCIN Diabetes Rats
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A study of process-induced grain structures during steady state and non-steady state electron-beam welding of a titanium alloy 被引量:4
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作者 Yu Lu Richard Turner +1 位作者 Jeffery brooks Hector Basoalto 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2022年第18期117-127,共11页
A detailed microstructural characterisation of the emerging weld-line grain structure,for bead-upon-plate welds in Ti-6Al-4V(Ti64)of differing plate thickness,was performed.The microstructure studied was formed during... A detailed microstructural characterisation of the emerging weld-line grain structure,for bead-upon-plate welds in Ti-6Al-4V(Ti64)of differing plate thickness,was performed.The microstructure studied was formed during both steady state and non-steady state sections within the weld path,with the non-steady state portion being taken from the end of the plate as the weld bead and heat source overhang the edge of the plate.This allows for the effects of welding process conditions on the microstructural evolution to be determined.The weld pool geometry and 3D tomography of the weld-induced defects have been investigated.Detailed characterisation of microstructure and texture for different welding parameters and for steady and non-steady states have been used to identify physical parameters for the microstructure predictions that are difficult to obtain otherwise.The different states significantly affect the weld crown shape and formation,weld toe,weld bead depth and width.However,the heat affected zone(HAZ)re-mains unchanged.Regarding the microstructural evolution,both the steady and non-steady states have similar microstructure and texture.No defects were observed in the steady state section of welds,but sub-surface spherical pores have been observed in the non-steady state section of a weld.Finite element modelling to simulate the thermal-metallurgical-mechanical fields within the steady and non-steady state sections of the welds was considered,and the cooling rates predicted within steady state and non-steady sections were interrogated to improve the theoretical understanding of the microstructure and defect formation differences in these Ti64 EB weld regions. 展开更多
关键词 Electron-beam fusion welding Processing Microstructure TI-6AL-4V
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中低收入国家药品定价和采购的政策选择 被引量:4
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作者 TuanAnh Nguyen Rosemary Knight +2 位作者 Elizabeth Ellen Roughead Geoffrey brooks Andrea Mant 《中国卫生政策研究》 CSCD 北大核心 2015年第4期1-11,共11页
药品支出上涨是全球问题。为应对这一压力,多数高收入国家制定并实施了一系列的药品定价和采购政策。然而,尽管中低收入国家希望能够有效控制药品支出预算,但其药品市场不规范,并缺乏可行的药品定价或采购政策。高收入国家药品支出通常... 药品支出上涨是全球问题。为应对这一压力,多数高收入国家制定并实施了一系列的药品定价和采购政策。然而,尽管中低收入国家希望能够有效控制药品支出预算,但其药品市场不规范,并缺乏可行的药品定价或采购政策。高收入国家药品支出通常由国家或社会医疗保险机构支付,而中低收入国家大多是个人自付,这会给政策执行造成阻力。由于对药品定价和采购政策是否高效缺乏严谨的调查研究,因而一定程度上阻碍了中低收入国家政策方案的实施。本文对已发表的有关药品定价和采购政策的文章进行综述发现,许多有效的政策也伴随着各种风险。全球尚没有一种最佳的政策选择,各国应根据具体国情,多种政策结合使用。中低收入国家的实证研究尚不足,由于缺乏完善的法律体系以及未建立专门的药品采购机构,任何一种政策选择所伴随的风险在这些国家都会引起更大的争议,然而这或许是帮助其改善药品定价和采购体系的关键因素。 展开更多
关键词 药品定价 药品采购 基于价值定价 药品支出 发展中国家
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Storylines of family medicine Ⅳ:perspectives on practice—lenses of appreciation
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作者 William B Ventres Leslie A Stone +15 位作者 Radeeb Akhtar Jeffrey M Ring Lucy M Candib Erick Messias Ronald M Epstein Marc Tunzi Amy L Lee Christopher P Morley Carina M Brown David Slawson Jill Konkin David G Campbell Ian Couper Susan Williams Robert brooks Lucie Walters 《Family Medicine and Community Health》 2024年第S03期33-42,共10页
Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians a... Storylines of Family Medicine is a 12-part series of thematically linked mini-essays with accompanying illustrations that explore the many dimensions of family medicine,as interpreted by individual family physicians and medical educators in the USA and elsewhere around the world.In‘Ⅳ:perspectives on practice—lenses of appreciation’,authors address the following themes:‘Relational connections in the doctor–patient partnership’,‘Feminism and family medicine’,‘Positive family medicine’,‘Mindful practice’,‘The new,old ethics of family medicine’,‘Public health,prevention and populations’,‘Information mastery in family medicine’and‘Clinical courage.’May readers nurture their curiosity through these essays. 展开更多
关键词 THEMATIC ILLUSTRATION DOCTOR
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在佛罗里达湾北部红树林的大红树(Rhizophora mangle)生境中发现蛀木等足动物钻孔团水虱(Sphaeroma terebrans) 被引量:4
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作者 R.Allen brooks 周立志 王翔 《AMBIO-人类环境杂志》 2004年第3期155-157,共3页
全世界的蛀木等足动物钻孔团水虱(Sphaeroma terebrans Bate)都生活在红树林根系所形成的潮间带生境中。在佛罗里达,它们几乎只专一地生活在大红树(Rhizophora mangle L.)红树林游离悬浮的气生根间,并且仅见于潮间带。由于钻孔团水... 全世界的蛀木等足动物钻孔团水虱(Sphaeroma terebrans Bate)都生活在红树林根系所形成的潮间带生境中。在佛罗里达,它们几乎只专一地生活在大红树(Rhizophora mangle L.)红树林游离悬浮的气生根间,并且仅见于潮间带。由于钻孔团水虱并不摄食蛀出的根系物质,它们和红树林之间并没有牧食关系。蛀洞一经建成,即可用于:①阻止非生物因子(暴露.干燥)和生物因子的干扰;②滤食活动(悬浮的沉积物、藻类和细菌);③繁殖和产后恢复。钻孔团水虱由于蛀洞对海上建筑设施的危害很大,因而造成巨大的经济损失。对于蛀洞的生物学意义争议很大,讨论的话题从等足动物引起的“生态灾难”到给红树林带来的益处。 展开更多
关键词 红树林 根系 动物 生境 气生根 林带 北部 潮间带 生物学意义 摄食
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Isolation and activation of collagenase from fish processing waste 被引量:4
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作者 Said M. Daboor Suzanne M. Budge +2 位作者 Abdel E. Ghaly Marianne S. brooks Deepika Dave 《Advances in Bioscience and Biotechnology》 2012年第3期191-203,共13页
Collagenase was isolated from fish waste (a mixture of haddock, herring, ground fish and flounder) using a Tris-buffer system. The proteins in the crude extract were precipitated using ammonium sulfate (40% - 80%) and... Collagenase was isolated from fish waste (a mixture of haddock, herring, ground fish and flounder) using a Tris-buffer system. The proteins in the crude extract were precipitated using ammonium sulfate (40% - 80%) and purified with gel-filtration chromatography using Sephadex G-100. The results showed that the collagenase enzyme was produced as a latent enzyme and was activated with bovine trypsin and potassium thiocyanate (KSCN). The enzyme activity was affected by pH and temperature. Optimal enzyme activities were found at 35?C and a pH of 7.5 when insoluble collagene type I was used as substrate and the liberated amino acids were measured in relation to L-leucine in the presence of ninhydrin. The enzyme activity was completely inhibited by the action of ethylenediaminetetraacetic acid (EDTA) suggesting that the collagenase enzyme isolated from the fish waste is a metalloproteinase enzyme requiring metal ions for enzyme activity. Dialysis against KSCN decreased the enzyme total activity and increased its specific activity. Sodium dodecyl sulphate polyacryla-mide gel electrophoresis (SDS-PAGE) indicated that the purified procollagenase enzyme have only one band at molecular weight of 50 kilodaltons (kDa). When the enzyme was cleaved with trypsin, it was found to consist of two subunits: a large unit with a molecular weight of 50 kDa and a small unit with a molecular weight of 10 kDa. 展开更多
关键词 Fish WASTE COLLAGENASE ENZYME Extraction PURIFICATION INHIBITORS ACTIVATORS
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