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1.
Though Hongbaekjeong(HBJ),a hebal mixture of three medicinal plants,has been traditionally used for arthritis and muscular pain,its scientific evidence still remains unclear.Thus,in the present study,analgesic and anti-inflammatory mechanism of HBJ was evaluated in vitro and in vivo.HBJ significantly reduced NO production and prostaglandin E2(PGE2)release and also attenuated the expression of cyclooxygenase 2(COX-2)in lipopolysaccharides(LPS)and interferon(IFN)-c treated RAW 264.7 cells.Furthermore,HBJ abrogated the production of proinflammatory cytokines such as interleukin(IL)1b,IL-6,IL-8 and monocyte chemoattractant protein-1(MCP-1)in LPS and IFN-c treated RAW 264.7 cells.In addition,HBJ significantly decreased the number of writhing syndrome induced by acetic acid,and also increased latency in hot-plate method and tail flick test in mice.Consistently,HBJ significantly reduced the edema volume in the hind paw of the rats with arthritis induced by Freund’s complete adjuvant(FCA)compared to untreated control.Collectively,our findings demonstrate the antiinflammatory and analgesic potential of HBJ via inhibition of proinflammatory cytokines and PGE2 release for treatment of arthritis and muscular pain.  相似文献   
2.
M West  W Menke  M Tolstoy  S Webb  R Sohn 《Nature》2001,413(6858):833-836
Axial volcano, which is located near the intersection of the Juan de Fuca ridge and the Cobb-Eickelberg seamount chain beneath the northeast Pacific Ocean, is a locus of volcanic activity thought to be associated with the Cobb hotspot. The volcano rises 700 metres above the ridge, has substantial rift zones extending about 50 kilometres to the north and south, and has erupted as recently as 1998 (ref. 2). Here we present seismological data that constrain the three-dimensional velocity structure beneath the volcano. We image a large low-velocity zone in the crust, consisting of a shallow magma chamber and a more diffuse reservoir in the lower crust, and estimate the total magma volume in the system to be between 5 and 21 km3. This volume is two orders of magnitude larger than the amount of melt emplaced during the most recent eruption (0.1-0.2 km3). We therefore infer that such volcanic events remove only a small portion of the reservoir that they tap, which must accordingly be long-lived compared to the eruption cycle. On the basis of magma flux estimates, we estimate the crustal residence time of melt in the volcanic system to be a few hundred to a few thousand years.  相似文献   
3.
该研究旨在检验在公寓建筑中自然通风的潜在利用对机械通风系统换气率的影响,以便提出适当的关于换气率的建议,现场测量在13栋公寓单元进行.测量时住宅内外的压力差有所变化.采用实测数据,对4Pa压力差下的换气率提出预测,换气率在每小时0.18~0,41间变化.  相似文献   
4.
Y Yoshikai  S P Clark  S Taylor  U Sohn  B I Wilson  M D Minden  T W Mak 《Nature》1985,316(6031):837-840
An essential property of the immune system is its ability to generate great diversity in antibody and T-cell immune responses. The genetic and molecular mechanisms responsible for the generation of antibody diversity have been investigated during the past several years. The gene for the variable (V) region, which determines antigen specificity, is assembled when one member of each of the dispersed clusters of V gene segments, diversity (D) elements (for heavy chains only) and joining (J) segments are fused by DNA rearrangement. The cloning of the beta-chain of the T-cell antigen receptor revealed that the organization of the beta-chain locus, which is similar to that of immunoglobulin genes, is also composed of noncontiguous segments of V, D, J and constant (C) region genes. The structure of the alpha-chain seems to consist of a V and a C domain connected by a J segment. We report here that the human T-cell receptor alpha-chain gene consists of a number of noncontiguous V and J gene segments and a C region gene. The V region gene segment is interrupted by a single intron, whereas the C region contains four exons. The J segments, situated 5' of the C region gene, are dispersed over a distance of at least 35 kilobases (kb). Signal sequences, which are presumably involved in DNA recombination, are found next to the V and J gene segments.  相似文献   
5.
D Lee  H Sohn  G V Kalpana  J Choe 《Nature》1999,399(6735):487-491
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6.
文中主要研究了植物过滤系统对改善室内空气品质的作用.通过实验比较了韩国本土和外来植物对室内空气污染物的净化作用.实验在夏季进行,将4种植物放入尺寸相同的样板房间,在相同实验条件下,对放入和未放入植物的样板房间内的苯、甲苯、乙苯、二甲苯和甲醛等有害物质的浓度加以监测,同时在植物放入3小时及3天后分别测定易挥发有机物(VOCs)的浓度;由此了解、比较和估计了两种外来植物和两种本土植物对易挥发有机化合物的净化效果.结果发现:(1)在所有实验中,置入植物的房间对VOCs物质的净化效果均比未置入植物的房间的大,而且外来植物对大多数VOCs物质的净化效果比本土植物更显著;(2)在种植和生长的空间实验中,本杰明橡胶树覆盖实验空间10%时净化效果最佳,该树对甲醛的净化效果尤其明显;(3)在种植和生长的空间实验中,盆栽金皇后种植在有阳光的地方时净化效果最佳,该植物对甲苯的净化效果最强.  相似文献   
7.

In this article we discuss how an interdisciplinary research team partnered with a variety of stakeholders concerned with and/or affected by the impacts of climate change in the Red River Delta of Vietnam. The research, undertaken from 2016 to 2018, drew upon a wide range of methods to investigate systemically these impacts – with a view to the research inputting into the development of (more) sustainable ways of living. The research solicited various accounts of the experience of climate change in the community, set up learning processes in community meetings, and created an interface with government officials positioned at commune, district, provincial, and national levels. The intention was to offer support towards developing a learning process (broadly defined as including learnings/systemic inquiry across organizational levels of the society) to pursue options for sustainable living. The article offers our post-facto reflections which render more explicit (to ourselves and for the benefit of audiences) how the research team, with Hoang as lead researcher, facilitated the inquiry process towards developing a synthesis which underscored the assets for resilience to climate change and supported interventions to strengthen such (defined) assets.

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8.
铜锍吹炼是铜精矿火法冶炼工艺的关键工序之一,目前全世界85%的冰铜均是采用PS转炉进行吹炼的。铜锍PS转炉吹炼是一个涉及化学反应、传热、传质的复杂的多相流体流动过程,吹炼过程中的流场分布特征、气锍渣分布规律以及物料混合特性对转炉生产率和铜回收率等指标起着重要影响。本文旨在通过可视化的冷态水模型试验模拟研究转炉吹炼高温冶炼过程流域分布和混合特性,进而对吹炼工艺进行优化。基于相似性原理建立了1:5等比例PS转炉冷态试验模型,采用高速摄像技术对吹炼过程的流场进行了动态记录,并基于图像处理技术对气液喷吹过程的流域进行了划分,包括喷吹区、喷溅区、强混合区、弱混合区、死区,并且对不同流域进行了定量化分析。此外,本文提出了一种新的判据,即“浓度稳定混合区波动极值”判据,用于判定不同示踪剂加入方式炉内的混合时间,进而确定了最佳的投料位置为喷吹波回落区,可明显提升转炉吹炼的混合效率。  相似文献   
9.
The gonadotropin receptors are G-protein-coupled receptors with unique structural and functional features, consisting of two halves. The N-terminal extracellular half (exodomain) binds the hormones, whereas the C-terminal membrane-associated half (endodomain) is responsible for receptor activation. In this review, the novel ternary interactions, contact points and mutual modulations among the exodomain, endodomain and hormone for hormone binding and signal generation are described based on the latest observations. This discussion is contrary to the view that the exodomain and endodomain are independent, at least functionally, and provides new insights into the receptor mechanisms for the gonadotropins and other G-protein-coupled receptors. Received 7 November 2001; received after revision 2 January 2002; accepted 3 January 2002  相似文献   
10.
为了从不锈钢粉尘中回收利用Fe,Cr和Ni等,对不锈钢粉尘热压块制备及其自还原过程进行了研究.在热压温度为200℃,热压压力为35 MPa条件下,抗压强度达到900 N/个以上.高温条件下,煤热解产生的挥发分可参与不锈钢粉尘还原反应,当还原温度为1 400,1 450℃时,挥发分还原作用率达到0.4.据XRD分析和热力学计算,自还原过程中含铬物质的物相转变顺序为Fe Cr2O4,Cr2O3,Cr7C3,[Cr]Fe-Cr-Ni-C.当还原温度为1 450℃,烟煤中固定碳与粉尘中可去除氧的物质量的比(xc/xo)为0.72时,不锈钢粉尘热压块不能完全还原;当xc/xo大于0.8,还原20 min时,不锈钢粉尘热压块能完全还原.  相似文献   
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