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塔里木克拉通北缘兴地镁铁—超镁铁质岩带铜镍成矿作用:来自铂族元素地球化学的制约
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作者 夏昭德 胡秀军 +5 位作者 杜玮 夏明哲 汪帮耀 焦建刚 张朋 王厚方 《地球科学与环境学报》 CAS 北大核心 2023年第5期1118-1131,共14页
兴地镁铁—超镁铁质岩带位于塔里木克拉通北缘的库鲁克塔格地块,由兴地Ⅰ号、Ⅱ号、Ⅲ号和Ⅳ号等岩体组成。其中,兴地Ⅰ号和Ⅳ号岩体以辉长岩相为主;而兴地Ⅱ号和Ⅲ号岩体从橄榄岩相、辉石岩相到辉长岩相均有产出,岩相分带清楚。兴地Ⅱ... 兴地镁铁—超镁铁质岩带位于塔里木克拉通北缘的库鲁克塔格地块,由兴地Ⅰ号、Ⅱ号、Ⅲ号和Ⅳ号等岩体组成。其中,兴地Ⅰ号和Ⅳ号岩体以辉长岩相为主;而兴地Ⅱ号和Ⅲ号岩体从橄榄岩相、辉石岩相到辉长岩相均有产出,岩相分带清楚。兴地Ⅱ号和Ⅲ号岩体二辉橄榄岩和二辉岩中均赋存有铜镍硫化物矿(化)体,常见矿石构造有星点状、斑点状、稀疏浸染状和稠密浸染状等,金属硫化物以磁黄铁矿、镍黄铁矿和黄铜矿为主。兴地Ⅱ号和Ⅲ号岩体岩石的铂族元素(PGE)含量(质量分数,下同)((0.41~4.54)×10^(-9))低,钯组铂族元素(PPGE)含量总体高于铱组铂族元素(IPGE),IPGE/PPGE值为0.08~0.48,原始地幔标准化铂族元素蛛网图呈左倾型。岩石中铂族元素相对于Ni和Cu明显亏损,Pd/Ir值为3.28~23.33,Ni/Cu值为3.67~10.00,表明其母岩浆为高镁玄武质岩浆,这与橄榄石-熔体平衡估算的母岩浆性质一致。全岩Cu/Pd值((6.58~83.33)×10^(4))以及Cu/Zr值与Ni含量的相关性特征表明,在岩浆源区和侵位过程中均发生了硫化物的熔离作用,导致残余岩浆中显著亏损铂族元素。综合分析认为,兴地Ⅱ号和Ⅲ号岩体具有良好的找矿前景。 展开更多
关键词 铜镍矿 铂族元素 矿石结构 硫化物 母岩浆 成矿作用 塔里木克拉通
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Myelinosome organelles in pathological retinas: ubiquitous presence and dual role in ocular proteostasis maintenance 被引量:1
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作者 Marina G.Yefimova 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第5期1009-1016,共8页
The timely and efficient elimination of aberrant proteins and damaged organelles, formed in response to various genetic and environmental stressors, is a vital need for all cells of the body. Recent lines of evidence ... The timely and efficient elimination of aberrant proteins and damaged organelles, formed in response to various genetic and environmental stressors, is a vital need for all cells of the body. Recent lines of evidence point out several non-classical strategies employed by ocular tissues to cope with aberrant constituents generated in the retina and in the retinal pigmented epithelium cells exposed to various stressors. Along with conventional strategies relying upon the intracellular degradation of aberrant constituents through ubiquitin-proteasome and/or lysosome-dependent autophagy proteolysis, two non-conventional mechanisms also contribute to proteostasis maintenance in ocular tissues. An exosome-mediated clearing and a myelinosome-driven secretion mechanism do not require intracellular degradation but provide the export of aberrant constituents and “waste proteins” outside of the cells. The current review is centered on the non-degradative myelinosome-driven secretion mechanism, which operates in the retina of transgenic Huntington’s disease R6/1 model mice. Myelinosome-driven secretion is supported by rare organelles myelinosomes that are detected not only in degenerative Huntington’s disease R6/1 retina but also in various pathological states of the retina and of the retinal pigmented epithelium. The intra-retinal traffic and inter-cellular exchange of myelinosomes was discussed in the context of a dual role of the myelinosome-driven secretion mechanism for proteostasis maintenance in different ocular compartments. Special focus was made on the interplay between degradative and non-degradative strategies in ocular pathophysiology, to delineate potential therapeutic approaches to counteract several vision diseases. 展开更多
关键词 autophagy Huntington’s disease Müller cells myelinosome-driven secretion myelinosomes ocular pathophysiology PROTEOSTASIS retina retinal pigmented epithelium ubiquitin-proteasome system
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中药饲料添加剂对岑溪古典鸡雏鸡生长性能的影响 被引量:5
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作者 左莲 《饲料博览》 CAS 2023年第1期66-68,共3页
为了探讨中药饲料添加剂对岑溪古典鸡雏鸡生长性能的影响,以1日龄岑溪古典鸡为试验动物进行饲养试验,将5000只1日龄岑溪古典鸡随机分为2个处理组,分别为对照组和试验组,每个处理5个重复,每个重复500只。在为期42d的饲养试验期间,对照组... 为了探讨中药饲料添加剂对岑溪古典鸡雏鸡生长性能的影响,以1日龄岑溪古典鸡为试验动物进行饲养试验,将5000只1日龄岑溪古典鸡随机分为2个处理组,分别为对照组和试验组,每个处理5个重复,每个重复500只。在为期42d的饲养试验期间,对照组饲喂基础饲粮,试验组全程饲喂基础饲粮+中药饲料添加剂300mg·kg^(-1)。结果表明:试验组在增重、采食量、成活率明显高于对照组(P<0.05)。说明中药饲料添加剂具有显著提高岑溪古典鸡生长性能的作用。 展开更多
关键词 中药饲料添加剂 古典鸡 生长性能
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临安大气污染本底站气溶胶特征分析 被引量:14
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作者 杨东贞 于晓岚 +3 位作者 李兴生 王超 Parungo F Nagamoto C 《大气科学》 CSCD 北大核心 1995年第2期219-227,T001,共10页
本文分析和讨论了1991年8月上旬至11月下旬在浙江临安大气污染本底站(属WMO)所监测的大气气溶胶及气溶胶中元素和离子的浓度、浓度的粒径分布、富集程度、型态特征及其相互关系等物理化学特征,还讨论了天气及某些气象要素... 本文分析和讨论了1991年8月上旬至11月下旬在浙江临安大气污染本底站(属WMO)所监测的大气气溶胶及气溶胶中元素和离子的浓度、浓度的粒径分布、富集程度、型态特征及其相互关系等物理化学特征,还讨论了天气及某些气象要素对气溶胶浓度分布特征的影响,对气溶胶的来源也作了简单探讨。 展开更多
关键词 气溶胶 浓度 粒径分布 大气污染
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非对称声源多极子随钻声波测井实验室测量研究 被引量:11
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作者 王兵 陶果 +1 位作者 陈天润 朱正亚 《地球物理学报》 SCIE EI CAS CSCD 北大核心 2012年第1期327-332,共6页
现有的随钻声波测井通常采用三种测量方式:单极子、偶极子及四极子测量模式.分别采用单极子源、偶极子源和四极子源激发单极子、偶极子和四极子信号对地层速度信息进行测量.由于随钻测井环境比较复杂,钻杆在井孔中占据大部分空间,钻杆... 现有的随钻声波测井通常采用三种测量方式:单极子、偶极子及四极子测量模式.分别采用单极子源、偶极子源和四极子源激发单极子、偶极子和四极子信号对地层速度信息进行测量.由于随钻测井环境比较复杂,钻杆在井孔中占据大部分空间,钻杆速度高于地层速度,导致接收到的信号中仪器波能量占主导,无法有效地提取地层的纵横波速度信息.本文探讨一种采用非对称偏心的点声源,一次激发,利用方位分布的四个接收器接收,经过合成后同时分别得到单极子、偶极子和四极子模式波信号的测量方法,为建立同时利用多极模式波信号测量地层纵横波速度的随钻声波测井实用技术提供基础.本文利用1∶12的缩比模型在实验室对该方法进行了考察,实验结果证明,可以通过非对称点声源得到有效的地层单极子、偶极子和四极子模式波信号.通过分析和对比实测数据和理论模拟的频散曲线,本文进一步提出利用三种模式波的频散曲线联合反演确定地层横波速度的方法. 展开更多
关键词 随钻声波测井 缩比模型 非对称偏心声源
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Variation of sulfate aerosol concentrations over the western Pacific and their effect on clouds, radiation and precipitation 被引量:1
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作者 F.Parungo J.Rosinski +1 位作者 M.L.C.Wu C.T.Nagamoto 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1993年第4期521-534,共14页
Under bilateral cooperation between the United States of America and the People's Republic of China, a series of research cruises were conducted over the western Pacific Ocean. It was found that a) the non-sea-sal... Under bilateral cooperation between the United States of America and the People's Republic of China, a series of research cruises were conducted over the western Pacific Ocean. It was found that a) the non-sea-salt sulfate aerosol particles are the major source of cloud condensation nuclei, b) the population of clouds and the total albedo are proportional to the concentration of condensation nuclei and consequently to the concentration of the non-sea-salt aerosol particles, and c) the amount of rainfall is inversely proportional to the concentration of non-sea-salt sulfate aerosol particles. It seems that anthropogenic sulfate aerosol particles affect the regional planetary albedo and climate and that the contribution from biogenically derived sulfate aerosol particles is of lesser importance. 展开更多
关键词 data Variation of sulfate aerosol concentrations over the western Pacific and their effect on clouds radiation and precipitation OVER
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New insights into sodium transport regulation in the distal nephron:Role of G-protein coupled receptors 被引量:1
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作者 Luciana Morla Aurélie Edwards Gilles Crambert 《World Journal of Biological Chemistry》 CAS 2016年第1期44-63,共20页
The renal handling of Na^+ balance is a major determinant of the blood pressure(BP) level. The inability of the kidney to excrete the daily load of Na+ represents the primary cause of chronic hypertension. Among the d... The renal handling of Na^+ balance is a major determinant of the blood pressure(BP) level. The inability of the kidney to excrete the daily load of Na+ represents the primary cause of chronic hypertension. Among the different segments that constitute the nephron, those present in the distal part(i.e., the cortical thick ascending limb, the distal convoluted tubule, the connecting and collecting tubules) play a central role in the fine-tuning of renal Na^+ excretion and are the target of many different regulatory processes that modulate Na^+ retention more or less efficiently. G-protein coupled receptors(GPCRs) are crucially involved in this regulation and could represent efficient pharmacological targets to control BP levels. In this review, we describe both classical and novel GPCR-dependent regulatory systems that have been shown to modulate renal Na^+ absorption in the distal nephron. In addition to the multiplicity of the GPCR that regulate Na^+ excretion, this review also highlights the complexity of these different pathways, and the connections between them. 展开更多
关键词 KIDNEY Sodium EXCRETION Blood pressure G-PROTEIN coupled RECEPTORS PEPTIDE HORMONE
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Antiplasmodial activity of traditional polyherbal remedy from Odisha, India:Their potential for prophylactic use 被引量:1
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作者 Prakash Bangalore Nagendrappa Jean-Francois Franetich +3 位作者 Frederick Gay Audrey Lorthiois Padma Venkatasubramanian Dominique Mazier 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2015年第12期982-986,共5页
Objective:To evaluate the potential prophylactic activity of traditional polyherbal remedy against malaria.Methods:A traditional polyherbal remedy against malaria from Odisha,India was evaluated for its potential prop... Objective:To evaluate the potential prophylactic activity of traditional polyherbal remedy against malaria.Methods:A traditional polyherbal remedy against malaria from Odisha,India was evaluated for its potential prophylactic activity using in vitro hepatic cell lines assay and the murine malaria system Plasmodium yoelii yoelii/Anopheles stephensi.Results:The polyherbal extract inhibited the Plasmodium yoelii hepatic stages in vitro(IC500.74 mg/m L),a therapeutic index of 9.54.In mice treated with the aqueous extract(2 000 mg/kg/day),peak parasitaemia values were 81%lower in the experimental2.35%±0.14%as compared to controls 12.62%±0.52%(P<0.001),suggesting significant prophylactic activity.Conclusions:The observations provide a proof of concept for a traditional malaria prophylactic remedy used by tribal populations in India. 展开更多
关键词 Polyherbal remedy PLASMODIUM Malaria prophylaxis Antiplasmodial activity
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中药提取物对种用凌云乌鸡公鸡精液品质的影响 被引量:2
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作者 许唯峰 《饲料博览》 CAS 2021年第4期37-39,共3页
为研究中药提取物(PE)对种用凌云乌鸡种公鸡精液品质的影响,试验选取合格的成年凌云乌鸡种公鸡300只,随机分为2组,每组3个重复组,每个重重50只鸡,对照组饲喂基础饲粮,试验组在基础饲粮上添加中药提取物300 mg·kg^(-1),进行为期5个... 为研究中药提取物(PE)对种用凌云乌鸡种公鸡精液品质的影响,试验选取合格的成年凌云乌鸡种公鸡300只,随机分为2组,每组3个重复组,每个重重50只鸡,对照组饲喂基础饲粮,试验组在基础饲粮上添加中药提取物300 mg·kg^(-1),进行为期5个月的饲养试验,测定分析采精量和精子浓度的差异。结果表明:试验组的采精量和精子浓度均明显高于对照组。说明中药提取物能显著提高凌云乌鸡种公鸡的精液品质。 展开更多
关键词 中药提取物 凌云乌鸡 种公鸡 精液品质
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中药提取物对凌云乌鸡蛋品质的影响 被引量:2
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作者 许唯峰 《饲料博览》 CAS 2021年第5期35-37,共3页
为研究中药(松针、丝瓜叶、泡桐花、贯众、伸筋草、老鹳草、钩吻)提取物对凌云乌鸡蛋品质的影响,试验随机选取40周龄体况一致的健康凌云乌鸡1800只,随机分为对照组和试验组,每组3个重复,每重复300只鸡,进行为期7周的饲养试验,其中预试期... 为研究中药(松针、丝瓜叶、泡桐花、贯众、伸筋草、老鹳草、钩吻)提取物对凌云乌鸡蛋品质的影响,试验随机选取40周龄体况一致的健康凌云乌鸡1800只,随机分为对照组和试验组,每组3个重复,每重复300只鸡,进行为期7周的饲养试验,其中预试期为1周,正试期为6周,对照组饲喂基础饲粮,试验组在基础饲粮基础上添加中药提取物500 mg·kg^(-1)。结果表明:试验组鸡的蛋黄比率、哈氏单位、蛋比重、蛋形指数、血肉斑率、蛋黄颜色显著高于对照组(P<0.05)。说明饲粮中添加中药提取物能够提高凌云乌鸡的蛋品质。 展开更多
关键词 中药提取物 凌云乌鸡 蛋品质
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Transient micro-elastography:A novel non-invasive approach to measure liver stiffness in mice 被引量:4
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作者 Cécile Bastard Matteo R Bosisio +5 位作者 Michèle Chabert Athina D Kalopissis Meriem Mahrouf-Yorgov Hélène Gilgenkrantz Sebastian Mueller Laurent Sandrin 《World Journal of Gastroenterology》 SCIE CAS CSCD 2011年第8期968-975,共8页
AIM:To develop and validate a transient micro-elastography device to measure liver stiffness(LS) in mice.METHODS:A novel transient micro-elastography(TME) device,dedicated to LS measurements in mice with a range of me... AIM:To develop and validate a transient micro-elastography device to measure liver stiffness(LS) in mice.METHODS:A novel transient micro-elastography(TME) device,dedicated to LS measurements in mice with a range of measurement from 1-170 kPa,was developed using an optimized vibration frequency of 300 Hz and a 2 mm piston.The novel probe was validated in a classical fibrosis model(CCl4) and in a transgenic murine model of systemic amyloidosis.RESULTS:TME could be successfully performed in control mice below the xiphoid cartilage,with a mean LS of 4.4 ± 1.3 kPa,a mean success rate of 88%,and an excellent intra-observer agreement(0.98).Treatment with CCl4 over seven weeks drastically increased LS as compared to controls(18.2 ± 3.7 kPa vs 3.6 ± 1.2 kPa).Moreover,fibrosis stage was highly correlated with LS(Spearman coefficient = 0.88,P < 0.01).In the amyloidosis model,much higher LS values were obtained,reaching maximum values of > 150 kPa.LS significantly correlated with the amyloidosis index(0.93,P < 0.0001) and the plasma concentration of mutant hapoA-□(0.62,P < 0.005).CONCLUSION:Here,we have established the first non-invasive approach to measure LS in mice,and have successfully validated it in two murine models of high LS. 展开更多
关键词 Transient elastography Micro-elastography Liver stiffness Liver MICE AMYLOIDOSIS FIBROSIS Ultrasound
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头位难产294例处理技术的临床研究 被引量:2
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作者 李宝珠 孙宁 《中国社区医师》 2015年第13期54-54,56,共2页
目的:探讨头位难产的发生原因及其临床处理技术。方法:2012年3月-2014年3月收治头位难产患者294例,对其临床资料进行回顾性分析。结果:产妇产道异常35例(11.9%),胎头位置异常220例(74.8%),产力异常(即宫缩乏力)39例(13.3%);实施剖宫产21... 目的:探讨头位难产的发生原因及其临床处理技术。方法:2012年3月-2014年3月收治头位难产患者294例,对其临床资料进行回顾性分析。结果:产妇产道异常35例(11.9%),胎头位置异常220例(74.8%),产力异常(即宫缩乏力)39例(13.3%);实施剖宫产211例(71.8%),实施阴道分娩83例(28.2%)。结论:在临床上一旦发现孕产妇存在头位难产,应依据孕产妇的实际状况选取恰当的处理方式,以便最大限度地降低母婴死亡率。 展开更多
关键词 头位难产 处理技术 分娩方式 异常
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Variability in Latent Heat Flux over the Tropical Pacific in Association with Recent Two ENSO Events 被引量:3
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作者 符淙斌 Henry Diaz 范慧君 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 1992年第3期351-358,共8页
This paper analyzed the variations of latent heat flux (LHF) over the tropical Pacific in the period 1978-1988 by using COADS (Comprehensive Ocean and Atmospheric Data Set). It has been founded that the interannual va... This paper analyzed the variations of latent heat flux (LHF) over the tropical Pacific in the period 1978-1988 by using COADS (Comprehensive Ocean and Atmospheric Data Set). It has been founded that the interannual variabili ty of LHF exhibits strong ENSO signal, with the significant increasing LHF during the recent two warm events, i.e., 1982 / 83 and 1986 / 87 and decreasing LHF in the cold episodes. However the longitudinal distribution of the LHF departures varies from event to event. In the eastern Pacific, the specific humidity difference at air-sea interface (qs -qa) makes a dominant contribution to the interannual variability of LHF ( r = 0.73 ), while in the western Pacific the surface wind speed, W and the qs - qa make nearly equal contribution to that of LHF. 展开更多
关键词 OVER Variability in Latent Heat Flux over the Tropical Pacific in Association with Recent Two ENSO Events ENSO
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Geographic and temporal variations of sulfate aerosols over the Pacific Ocean
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作者 F.Parungo C.Nagamoto +2 位作者 B.Kopcewicz J.Harris S.Hoyt 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第1期47-71,共25页
To investigate the life cycle of marine sulfate aerosols, chemicophysical characteristics of marine aerosolswere measured during five cruises in the Pacific Ocean. Dimethyl sulfide concentrations in seawater and in th... To investigate the life cycle of marine sulfate aerosols, chemicophysical characteristics of marine aerosolswere measured during five cruises in the Pacific Ocean. Dimethyl sulfide concentrations in seawater and in the air were also measured. The geographic variation of sulfate-aerosol concentrations was studied in relation to biogenic and anthropogenic sources,transport with air trajectories, and chemical transformations in the atmosphere. The highest concentrations were found near Asian and American ports, indicating anthropogenic pollution is the major sulfate aerosols source. Higher concentrations were observed in the upwelling regions than in the oligotrophic areas. Along the coastal regions, both mass and number concentrations of sulfate aerosols depended on wind direction and wind speed, and land-breeze and sea-breeze oscillations; no clear diurnal variation was detected. In pelagic areas, along the equator, the concentrations of small sulfate particles showed a maximum in the afternoon and the minimum at night , indicating photo-oxidation as an important process for gas-to-particle conversion. Higher sulfate-aerosol concentrations were observed in spring than in autumn and higher concentrations were found during the La Nina anomaly than during the El Nino anomaly. Biogenic source of sulfate aerosols has an important role in the remote ocean. Case studies of sulfate-aerosol distributions are discussed. 展开更多
关键词 DMS Geographic and temporal variations of sulfate aerosols over the Pacific Ocean OVER
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Novel Ferricenium Tetrafluoroborate Salt as Latent Thermal Cationic Initiator for Curing of Epoxy Resins 被引量:1
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作者 王涛 王志华 刘金萍 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2004年第4期570-573,共4页
A novel latent thermal initiator, ferricenium tetrafluoroborate salt (FcBF4), for cationic polymerization of epoxides is reported. The activities of FcBF4 for different epoxides, including bisphenol-A-type epoxy oligo... A novel latent thermal initiator, ferricenium tetrafluoroborate salt (FcBF4), for cationic polymerization of epoxides is reported. The activities of FcBF4 for different epoxides, including bisphenol-A-type epoxy oligomer E44, cycloaliphatic epoxy ERL4221, and glycidylether epoxy GGE, were evaluated by differential scanning calorimetry (DSC). The results showed a moderate thermal initiation activity for E44 and GGE at 78℃ and 108℃ respectively. When adding GGE to E44, the reaction was enhanced. The temperature of thermal degradation of the cured specimens for the system of E44/FcBF4, E44+10%GGE/FcBF4 and E44+10%ERL4221/FcBF4 is higher than 350℃. 展开更多
关键词 latent thermal initiator cationic polymerization ferricenium salt
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Extrahepatic hepcidin production:The intriguing outcomes of recent years
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作者 Raêd Daher Thibaud Lefebvre +1 位作者 HervéPuy Zoubida Karim 《World Journal of Clinical Cases》 SCIE 2019年第15期1926-1936,共11页
Hepcidin is the hyposideremic hormone regulating iron metabolism.It is a defensin-like disulfide-bonded peptide with antimicrobial activity.The main site of hepcidin production is the liver where its synthesis is modu... Hepcidin is the hyposideremic hormone regulating iron metabolism.It is a defensin-like disulfide-bonded peptide with antimicrobial activity.The main site of hepcidin production is the liver where its synthesis is modulated by iron,inflammation and erythropoietic signaling.However,hepcidin locally produced in several peripheral organs seems to be an important actor for the maintenance of iron homeostasis in these organs.This review highlights the presence of peripheral hepcidin and its potential functions.Understanding the role of extrahepatic hepcidin could be of great physiological and therapeutic importance for several specific pathologies. 展开更多
关键词 HEPCIDIN EXTRAHEPATIC HEPCIDIN Iron METABOLISM BACTERIAL INFECTION Inflammation
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Proteomic studies of arbuscular mycorrhizal associations
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作者 Manuel Sebastián Rebollo Couto Paulo Emilio Lovato +1 位作者 Daniel Wipf Eliane Dumas-Gaudot 《Advances in Biological Chemistry》 2013年第1期48-58,共11页
Arbuscular mycorrhizal (AM) fungi are soil-borne microorganisms forming mutualistic associations with the vast majority of land plants, including most agricultural relevant crops. In this association the plant provide... Arbuscular mycorrhizal (AM) fungi are soil-borne microorganisms forming mutualistic associations with the vast majority of land plants, including most agricultural relevant crops. In this association the plant provides the fungus with plant photosynthates allowing it to complete its life cycle, while the fungus provides the plant with mineral nutrients, mainly phosphorus and can also help the plant to tolerate biotic and abiotic stresses. In regard to these benefits there is growing interest on the use of AM fungi to improve productivity and sustainability in agricultural systems. AM fungi and their interactions with plants have been extensively studied using proteomic techniques, but some difficulties have been faced. 1) Little is known about the AM fungal typical protein repertoire because it is currently impossible to grow AM fungi in pure axenic cultures;2) Plant tissues often contain high amounts of interfering substances that make protein extraction for the study of AM interactions a difficult procedure;3) Most nutrient exchanges between AM fungi and their host plants involve participation of membrane proteins, still poorly resolved in most separation techniques. Finally, 4) the formation of the arbuscule is an asynchronous process, making it difficult to distinguish which proteins are essential in the early or late stages of AM associations. In this review we present a historical summary of how these difficulties have been overcome by technological advances in proteomics and we discuss current and future trends in the study of the proteins involved in AM interactions. 展开更多
关键词 MYCORRHIZA SYMBIOSIS PROTEOMICS 2DE MASS SPECTROMETRY
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Automatic Optimization of Chirp Setting Parameters in Medical Ultrasound Contrast Imaging
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作者 Amira Zaylaa Sebastien Menigot +1 位作者 Jamal Charara Jean-Marc Girault 《Journal of Life Sciences》 2013年第6期592-598,共7页
Medical ultrasound contrast imaging is a powerful modality undergoing successive developments in the last decade to date Lately, pulse inversion has been used in both ultrasound tissue harmonic and contrast imaging. H... Medical ultrasound contrast imaging is a powerful modality undergoing successive developments in the last decade to date Lately, pulse inversion has been used in both ultrasound tissue harmonic and contrast imaging. However, there was a tradeoff between resolution and penetration. Chirp excitations partially solved the tradeoff, but the chirp setting parameters were not optimized. The present work proposes for the first time combining chirp inversion with ultrasound contrast imaging, with the motivation to improve the contrast, by automatically optimizing the setting parameters of chirp excitation, it is thus an optimal command problem. Linear chirps, 5 μm diameter microbubbles and gradient ascent algorithm were simulated to optimize the chirp setting parameters. Simulations exhibited a gain of 5 dB by automatic optimization of chirp inversion relative to pulse inversion. The automatic optimization process was quite fast. Combining chirp inversion with ultrasound contrast imaging led to a maximum backscattered power permitting high contrast outcomes and optimum parameters. 展开更多
关键词 Medical ultrasound contrast imaging chirp inversion chirp setting parameters automatic technique optimal command.
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Oncologic Trogocytosis Protects Tumour Stromal Cells from γδ Cell Cytotoxicity
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作者 Emilie Decaup Pej man Mirshahi +3 位作者 Arash Rafii Massoud Mirshahi Jean-Jacques Foumie Mary Poupot 《Journal of Life Sciences》 2011年第12期986-995,共10页
Tumours progressively develop chemoresistance and immunoescape abilities thanks to support from their stromal microenvironment. In ovarian carcinomas, for instance, tumour-associated mesenchymal stem cells (TAMC) ca... Tumours progressively develop chemoresistance and immunoescape abilities thanks to support from their stromal microenvironment. In ovarian carcinomas, for instance, tumour-associated mesenchymal stem cells (TAMC) can transfer multi-drug-resistant proteins to develop metastases. However, since the microenvironment of such carcinomas is frequently infiltrated by both TAMC and γδ T lymphocytes, the consequences of interactions between these cell types were unclear. Here, we report that whilst γδ T lymphocytes were not activated when co-incubated in vitro with TAMC, their cell membranes were trogocytosed by the TAMC. Since TAMC constitutively express a low level of HLA class I, which is increased by trogocytosis of γδ cell-derived HLA class I, the interaction increased the expression of HLA class-I molecules on TAMC. In addition, γδ T lymphocytes are HLA-unrestricted cytolytic cells and their activity is regulated by inhibitory receptors (KIR) for self-HLA class I. Hence, although the lytic activity of γδ T lymphocytes for unrelated target cells was unaffected by trogocytosis, it spared the TAMC. Therefore, interactions between TAMC and cytolytic γδ T cells avoided the killing of these stromal cells due to an active transfer of their protective HLA class-I molecules. These results suggest that trogocytosis contributes to the maintenance of cancer-associated stromal cells. 展开更多
关键词 Membrane transfer tumour microenvironment stromal cells HLA-class I molecules
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酵素饲料对绿壳蛋鸡蛋品质的影响
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作者 覃子榕 林夏 +1 位作者 左莲 葛洪伟 《饲料博览》 CAS 2022年第4期43-45,共3页
为研究复方酵素饲料对绿壳蛋鸡蛋品质的影响,试验选取已过产蛋高峰期的、体况一致的健康绿壳蛋鸡1200只,随机分为2组(对照组和试验组),每组3个重复,对照组饲喂基础饲粮,试验组在基础饲粮中添加2%酵素饲料,进行为期5周的饲养试验,其中预... 为研究复方酵素饲料对绿壳蛋鸡蛋品质的影响,试验选取已过产蛋高峰期的、体况一致的健康绿壳蛋鸡1200只,随机分为2组(对照组和试验组),每组3个重复,对照组饲喂基础饲粮,试验组在基础饲粮中添加2%酵素饲料,进行为期5周的饲养试验,其中预试期为1周,正试期为4周。结果表明:试验组的蛋黄比率、哈氏单位、蛋比重、血肉斑率、蛋黄颜色显著高于对照组(P<0.05)。说明饲粮中添加酵素饲料能够提高绿壳蛋鸡的蛋品质。 展开更多
关键词 酵素饲料 绿壳蛋鸡 蛋品质
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