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癌变机制分析

第四军医大学学报 2005年第19期26卷 1813-1815页

作者：张丰李青第四军医大学西京医院病理科陕西西安710033

0 引言虽然近几十年来在肿瘤研究方面取得了很大进展,但是至今关于肿瘤的具体发生机制还存在争论和分歧,主要存在基因突变假说和非整倍体假说的分歧. 基因突变假说认为几个重要基因的独立突变可以导致肿瘤的发生;但非整倍体假说认为非... 详细信息

0 引言虽然近几十年来在肿瘤研究方面取得了很大进展,但是至今关于肿瘤的具体发生机制还存在争论和分歧,主要存在基因突变假说和非整倍体假说的分歧. 基因突变假说认为几个重要基因的独立突变可以导致肿瘤的发生;但非整倍体假说认为非整倍体是肿瘤产生的根源. 在这里,我们通过分析基因突变和非整倍体在肿瘤干细胞产生过程中的作用,提出了新的肿瘤发生机制假说.[第一段]

关键词：基因突变非整倍体肿瘤干细胞永生化DNA链端粒

马钱子药膏改善颈椎病患者周围神经压迫症状:随机对照306例效果观察

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中国组织工程研究与临床康复 2007年第23期11卷 4531-4533页

作者：李全李福安卢坚深圳市中医院骨科广东省深圳市518033

目的:观察马钱子药膏改善颈椎病患者周围神经压迫症状的临床效果,并与扶他林软膏进行对照。方法:将2002-06/2005-11到深圳市中医院门诊就诊的360例颈型、神经根型颈椎病患者随机分为治疗组185例和对照组175例,治疗组采用马钱子药膏,对... 详细信息

目的:观察马钱子药膏改善颈椎病患者周围神经压迫症状的临床效果,并与扶他林软膏进行对照。方法:将2002-06/2005-11到深圳市中医院门诊就诊的360例颈型、神经根型颈椎病患者随机分为治疗组185例和对照组175例,治疗组采用马钱子药膏,对照组采用扶他林软膏,均外用于颈项部,每天外搽3次,每次五六分钟,7d为1个疗程,持续治疗4周,每周观察记录1次。将颈项部疼痛、上肢放射痛、上肢麻木症状按轻重不同分别计为0,1,2,3分。同时参照2002年卫生部颁发的《中药新药临床研究指导原则》中关于颈椎病的诊断疗效标准判定疗效。结果:360例患者均进入结果分析。①治疗组治疗1,2,3,4周颈项痛、放射痛评分低于对照组(P<0.05或0.01)。治疗组治疗2,3,4周上肢麻木症状低于对照组(P<0.05或0.01)。对各症状的缓解主要体现在治疗的第1,2周,治疗第3,4周时效果趋于稳定,与治疗2周后的差异不明显。②治愈率和总有效率:治疗组高于对照组(41.6%,33.1%;92.4%,85.8%,P<0.05)。③治疗组有14例患者出现皮肤瘙痒症状,9例患者出现敷药部位的皮肤潮红,其中严重的有2例患者出现皮肤小水疱,对照组10例患者出现皮肤瘙痒症状,6例患者出现敷药部位的皮肤潮红,但经过正确的局部处理措施后,症状缓解。结论:马钱子药膏对颈项痛、上肢放射痛、上肢麻木等症状具有可靠的治疗效果,该药对上述症状的改善要优于扶他林软膏。

关键词：颈椎病/中医药疗法外治法马钱子药膏临床研究

HEAT TRANSFER BEHAVIOR OF SUPERALLOY DROPLETS DURING SPRAY FORMING

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 800-805页

作者： J.F. Sun, J. Shen, Z. Y. li, J. Jia and q.C. li National Key Laboratory of Metal Precision Hot Processing, Harbin Institute of Technology, Harbin 150001, China

Based on the Newtonian heat transfer formulation and classical heterogeneous nucleation theory, a mathematical model has been established to predict the profile of flight velocity, heat transfer coefficient, temperature, solid fraction and cooling rate of atomizing droplets for a superalloy. The results indicated that above parameters change with different droplet size and flight distance. The changing trend as well as the mechanism for the change are described and discussed.

关键词： spray forming superalloy heat transfer mathematical model

Numerical Investigation of Penetration Performance of Non-Ideal Segmented-Rod Projectiles

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Transactions of Tianjin University 2008年第6期14卷 391-395页

作者： ALY S Y School of Mechanical Aerospace and Civil EngineeringThe University of Manchester

The design of a segmented-rod projectile is often simplified into an ideal one in theoreti-cal analysis for the convenience of modeling of its *** the actual performance of non-ideal segmented-rod projectiles over the impact velocity range in practical applications was rarely *** numerical code is used to investigate the influence of the component design upon the penetration performance of non-ideal segmented-rod projectiles over a wide range of impact velocities,which can be used to guide the optimal design of weaponry segmented-rod projectiles.

关键词： penetration segmented-rod projectile numerical simulation

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基于30m地表覆盖数据的城市扩张测度方法

中国科学：地球科学 2016年第9期46卷 1180-1187页

作者：于溪张冰琦李强陈晋北京师范大学资源学院北京100875 北京师范大学地表过程与资源生态国家重点实验室北京100875

利用2000和2010年的全球30m分辨率地表覆盖数据,以我国320个地级以上城市为对象,建立城市扩张强度的对数正态分布拟合模型,并提出测度城市扩张强度基本特征的峰位置、半峰宽和偏度等参数.结果表明:对数正态分布拟合方法能够表征中国城... 详细信息

利用2000和2010年的全球30m分辨率地表覆盖数据,以我国320个地级以上城市为对象,建立城市扩张强度的对数正态分布拟合模型,并提出测度城市扩张强度基本特征的峰位置、半峰宽和偏度等参数.结果表明:对数正态分布拟合方法能够表征中国城市扩张强度随距离而变化的空间分布规律及其差异,具有代表性、区分性和一定的鲁棒性与抗干扰能力.特征参数进一步揭示出不同规模城市扩张的差异性,即:规模较大城市具有强烈的向外围扩张趋势,且扩张强度和影响力高于其他城市,但大多数城市的扩张发生在距城市中心较近的区域,影响范围有限;城市扩张强度及空间延续性与城市原有规模密切相关.

关键词：城市化城市扩张遥感对数正态分布特征参数全球30m地表覆盖数据

Low-Loss, Broadband and Tunable Negative Refractive Index Metamaterial

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Journal of Electromagnetic Analysis and Applications 2010年第2期2卷 104-110页

作者： Y.J. Huang G.J. Wen T.q. li K. Xie 不详

This paper report on a low-loss, broadband, and tunable negative refractive index metamaterial (NRIM) consisting of yttrium iron garnet (YIG) slabs and printed circuit boards (PCBs). The YIG slabs under an applied magnetic field provide a negative permeability and the PCBs provide a negative permittivity. The substrates of the PCBs decuple the interactions between the YIG slabs and wire array deposed on such substrates. The effective electromagnetic parameters of the NRIM and the conditions of exhibiting the negative refractive index character are analyzed theoretically. Then the negative transmission and negative refraction characters are investigated numerically and experimentally. The results indicate that the NRIM exhibits negative pass band within the X-band with a bandwidth of about 1 GHz and a peak transmission power of about - 2.5 dB. While changing the applied magnetic field from 2300 Oe to 2700 Oe, the measured pass band of NRIM shift from 8.42 GHz to 9.50 GHz with a 2.7 MHz/Oe step. The results open a sample way to fabricate the NRIM, further, the metamaterial cloak and absorber.

关键词： Metamaterial Negative Refractive Index Tunability Low-Loss Broadband

EFFECTS OF STRUCTURAL DIMENSIONS AND MATERIAL PROPERTIES ON THE BLAST LOADING AND DYNAMIC ELASTIC RESPONSE OF CONTAINMENT VESSELS

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EFFECTS OF STRUCTURAL DIMENSIONS AND MATERIAL PROPERTIES ON ...

The Lobster Eye Imager for Astronomy Onboard the SATech-01 Satellite

The 7th International Conference on Shock and Impact Loads on Structures

作者： q.Dong The University of Manchester United Kingdom q.M.li~* The University of Manchester United Kingdom J.Y.Zheng Zhejiang University China

＜正＞The blast loading and dynamic elastic response of a containment vessel due to the internal detonation of a high explosive are studied in this *** on the parametric analyses on the structural dimensions and material properties of containment vessels,the interactions between the blast loading and dynamic elastic response of containment vessels are investigated in the primary-shock period and the shock-reflection *** is shown that the density and the thickness of the vessel may affect the peak overpressure in the primary-shock period while resonance or beating may happen when the frequency of the reflected shock waves is close to the frequency of the breathing mode in the shock-reflection *** addition,the ratio of thickness to radius is a very sensitive factor for affecting the occurrence of strain growth in containment *** effects of the thickness-toradius ratio on the degree of strain growth are examined to assist engineering design. The fundamental features of the dynamic elastic response of containment vessels are investigated through an elastic circular plane-strain ring subjected to internal blast loading（or an infinite cylindrical shell subjected to an internal linear blast loading along its axis） using the dynamic nonlinear finite element program LS-DYNA.

关键词： structural dimension material property blast loading dynamic elastic response containment vessel

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Research in Astronomy and Astrophysics 2023年第9期23卷 66-78页

作者： Z.X.ling X.J.Sun C.Zhang S.L.Sun G.Jin S.N.Zhang X.F.Zhang J.B.Chang F.S.Chen Y.F.Chen Z.W.Cheng W.Fu Y.X.Han H.li J.F.li Y.li Z.D.li P.R.liu Y.H.Lv X.H.Ma Y.J.Tang C.B.Wang R.J.Xie Y.L.Xue A.L.Yan q.Zhang C.Y.Bao H.B.Cai H.q.Cheng C.Z.Cui Y.F.Dai D.W.Fan H.B.Hu J.W.Hu M.H.Huang Z.q.Jia C.C.Jin D.Y.li J.q.li H.Y.liu M.J.liu Y.liu H.W.Pan Y.L.qiu M.Sugizaki H.Sun W.X.Wang Y.L.Wang q.Y.Wu X.P.Xu Y.F.Xu H.N.Yang X.Yang B.Zhang M.Zhang W.D.Zhang Z.Zhang D.H.Zhao X.q.Cong B.W.Jiang L.H.li X.B.qiu J.N.Sun D.T.Su J.Wang C.Wu Z.Xu X.M.Yang S.K.Zhang Z.Zhang N.Zhang Y.F.Zhu H.Y.Ban X.Z.Bi Z.M.Cai W.Chen X.Chen Y.H.Chen Y.Cui X.L.Duan Z.G Feng Y.Gao J.W.He T.He J.J.Huang F.li J.S.li T.J.li T.T.li H.q.liu L.liu R.liu S.liu N.Meng q.Shi A.T.Sun Y.M.Wang Y.B.Wang H.C.Wu D.X Xu Y.q Yang Y.Yang X.S.Yu K.X.Zhang Y.L.Zhang Y.H.Zhang Y.T.Zhang H.Zhou X.C.Zhu J.S.Cheng L.qin L.Wang q.L.Wang M.Bai R.L.Gao Z.Ji Y.R.liu F.L.Ma Y.J.Shi J.Su Y.Y.Tan J.Z.Tong H.T.Xu C.B.Xue G.F.Xue W.Yuan National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China School of Astronomy and Space Science University of Chinese Academy of SciencesBeijing 100049China Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083China North Night Vision Technology Co. LTDNanjing 211106China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China Science and Technology on Low-light-Level Night Vision Laboratory Xi'an 710065China Innovation Academy for Microsatellites Chinese Academy of SciencesShanghai 201204China Institute of Electrical Engineering Chinese Academy of ScienceBeijing 100190China National Space Science Center Chinese Academy of ScienceBeijing 100190China

The Lobster Eye Imager for Astronomy(LEIA),a pathfinder of the Wide-field X-ray Telescope of the Einstein Probe mission,was successfully launched onboard the SATech-01 satellite of the Chinese Academy of Sciences on2022 July *** this paper,we introduce the design and on-ground test results of the LEIA *** stateof-the-art Micro-Pore Optics(MPO),a wide field of view of 346 square degrees(18.6°×18.6°)of the X-ray imager is *** optical assembly composed of 36 MPO chips is used to focus incident X-ray photons,and four large-format complementary metal-oxide semiconductor(CMOS)sensors,each of size 6 cm×6 cm,are used as the focal plane *** instrument has an angular resolution of 4’-8’(in terms of FWHM)for the central focal spot of the point-spread function,and an effective area of 2-3 cm^(2) at 1 keV in essentially all the directions within the field of *** detection passband is 0.5-4 keV in soft X-rays and the sensitivity is2-3×10^(-11) erg s^(-1) cm^(-2)(about 1 milliCrab)with a 1000 s *** total weight of LEIA is 56 kg and the power is 85 *** satellite,with a design lifetime of 2 yr,operates in a Sun-synchronous orbit of 500 km with an orbital period of 95 *** is paving the way for future missions by verifying in flight the technologies of both novel focusing imaging optics and CMOS sensors for X-ray observation,and by optimizing the working setups of the instrumental *** addition,LEIA is able to carry out scientific observations to find new transients and to monitor known sources in the soft X-ray band,albeit with limited useful observing time available.

关键词： instrumentation detectors-space vehicles instruments-telescopes-X-rays genera

Awakening concentration of desflurane is decreased in patients with obstructive jaundice

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第二军医大学学报 2006年第4期27卷 377-377页

作者： Song JG Cao YF Yang Lq Yu WF li q Song JC Fu XY Fu q Department of Anesthesiology Eastern Hepatobiliary Surgery Hospital Second Military Medical University Shanghai 200438 China