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Chain-type wireless sensor network node scheduling strategy 被引量:9
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作者 Guangzhu Chen Qingchun Meng Lei Zhang 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2014年第2期203-210,共8页
In order to reduce power consumption of sensor nodes and extend network survival time in the wireless sensor network (WSN), sensor nodes are scheduled in an active or dormant mode. A chain-type WSN is fundamental y ... In order to reduce power consumption of sensor nodes and extend network survival time in the wireless sensor network (WSN), sensor nodes are scheduled in an active or dormant mode. A chain-type WSN is fundamental y different from other types of WSNs, in which the sensor nodes are deployed along elongated geographic areas and form a chain-type network topo-logy structure. This paper investigates the node scheduling prob-lem in the chain-type WSN. Firstly, a node dormant scheduling mode is analyzed theoretical y from geographic coverage, and then three neighboring nodes scheduling criteria are proposed. Sec-ondly, a hybrid coverage scheduling algorithm and dead areas are presented. Final y, node scheduling in mine tunnel WSN with uniform deployment (UD), non-uniform deployment (NUD) and op-timal distribution point spacing (ODS) is simulated. The results show that the node scheduling with UD and NUD, especial y NUD, can effectively extend the network survival time. Therefore, a strat-egy of adding a few mobile nodes which activate the network in dead areas is proposed, which can further extend the network survival time by balancing the energy consumption of nodes. 展开更多
关键词 wireless sensor network (WSN) chain-type nodescheduling network survival time mobile nodes.
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Cauchy Problem for System of Ferro-Magnetic Chain Type 被引量:4
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作者 周毓麟 孙和生 郭柏灵 《Science China Mathematics》 SCIE 1993年第8期927-939,共13页
In this paper, we have established the existence theorem of the weak solution of theboundary problems for systems of ferro-magnetic chain ty means of the viscosity eliminatingmethod and the Leray-Schauder fixed point ... In this paper, we have established the existence theorem of the weak solution of theboundary problems for systems of ferro-magnetic chain ty means of the viscosity eliminatingmethod and the Leray-Schauder fixed point argument. 展开更多
关键词 SYSTEM of ferro-magnetic chain type SPIN SYSTEM CAUCHY problem method of viscosity elimination.
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Multidimensional System of Ferro-magnetic Chain Type~* 被引量:2
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作者 周毓麟 孙和生 郭柏灵 《Science China Mathematics》 SCIE 1993年第12期1422-1434,共13页
The global solvability of homogeneous boundary problem for a class of multidimensional generalized system of ferro-magnetic chain type is considered.
关键词 MULTIDIMENSIONAL SYSTEM of ferro-magnetic chain type SPIN SYSTEM HOMOGENEOUS boundary problem Galerkin’s method.
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A Chain of Type Ⅱ and Its Exact Solutions
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作者 张宇 周汝光 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第11期9-12,共4页
The exact solutions of a chain of type Ⅱ are investigated. The chain of type Ⅱ is first transformed to an integrable differential-difference equation, which has the Kaup Newell spectral problem as its continuous spa... The exact solutions of a chain of type Ⅱ are investigated. The chain of type Ⅱ is first transformed to an integrable differential-difference equation, which has the Kaup Newell spectral problem as its continuous spatial spectral problem and a Darboux transformation of the Kaup-Newell equation as its discrete temporal spectral problem. Then, with these spectral problems, a Darboux transformation of the transformed equation is constructed. Finally, as an application of the Darboux transformation, an exact solution of the transformed equation and thus the chain of type Ⅱ are presented. 展开更多
关键词 of ET for that and Its Exact Solutions A chain of type is HAVE
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A NEW TYPE OF CHAIN COMPOUND,STRUCTURE OF TA_4(TE_2)_4TE_4I
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作者 Shui Quan DENG Hong Hui ZHUANG Ding Ming WU Jin Ling BUANG Fujian Institute of Research on the Structure of Matter,Chinese Academy of Sciences and State Key Laboratory of Structure Chemistry,Fuzhou,Fujian 350002 《Chinese Chemical Letters》 SCIE CAS CSCD 1993年第3期273-274,共2页
Ta_4(Te_2)_4Te_4I,Mr=2381.90,Monoclinic,C2/c,a=21.987(2),b=6.153(2),c= 19.936(3),β=122.42(14),V=2276.7 ~3,z=4,Dm=6.8(5)g/cm^3,Dc=6.95g/cm^3,λ(Mok)= 0.71073,μ=354.0cm^(-1),F(000)=3876,T=296(1)k,R=5.3%,Rw=6.8%,for 11... Ta_4(Te_2)_4Te_4I,Mr=2381.90,Monoclinic,C2/c,a=21.987(2),b=6.153(2),c= 19.936(3),β=122.42(14),V=2276.7 ~3,z=4,Dm=6.8(5)g/cm^3,Dc=6.95g/cm^3,λ(Mok)= 0.71073,μ=354.0cm^(-1),F(000)=3876,T=296(1)k,R=5.3%,Rw=6.8%,for 1118 unique observed reflections(1>3σ(Ⅰ)).The structure is composed of [Ta_4(Te_2)_4Te_4I]_∞~ chains,which are formed by the four-nuclear butterfly cluster units "Ta_4(Te_2)_4Te_4" with the Ⅰ atoms as the bridging atoms between different cluster units. 展开更多
关键词 TA TE A NEW type OF chain COMPOUND STRUCTURE OF TA4 TE2
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Production and Characterization of Recombinant Rat Non-Collagen Domain of α3 Chain of Type IV Collagen α3 (IV) NC1 Antigen
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作者 Afsana Munni 《CellBio》 2016年第3期27-48,共22页
The glomerulonephritis disease is characterized by inflammation of glomeruli or small blood vessels in the kidney that causes kidney diseases. The reason of glomerulonephritis disease is to deposit the anti-GBM auto a... The glomerulonephritis disease is characterized by inflammation of glomeruli or small blood vessels in the kidney that causes kidney diseases. The reason of glomerulonephritis disease is to deposit the anti-GBM auto antibody in the glomerular basement membrane. The type IV collagen is the main component of glomerular basement membrane that has α3 chain of type (IV) collagen of non-collagenous domain which contains N-terminal 7S domain, a triple helical collagenous domain and C-terminal non-collagenous glomerular domain (NC1). The amino terminal of α3 (IV) NC1 that induces the Experimental Autoimmuno Glomerulonephritis (EAG) in rat model has been identified. The recombinant rat α3 (IV) NC1 antigen has nine amino acid spans that are consistent with antibody or T cell epitope that induces in EAG. The research is carried out on the recombinant rat α3 (IV) NC1 production, purification, quantification, and characterization. The circulation of anti-GBM antibody in glomerular basement membrane can be measured by the ELISA assay. In addition, the recombinant rat antigen is secreted in HEK293 cell supernatant that is purified by Anti-FLAG M2 monoclonal IgG antibody affinity column and characterized and quantified by SDS-PAGE gel electrophoresis and Western blotting techniques. 展开更多
关键词 Auto-Immuno Kidney Disease Glomerulonephritis Disease Glomerular Basement Membrane α3 (IV) NC1-Non-Collagen Domain of α3 chain of type IV Collagen α3 (IV) Antibody(Ab) Antigen (Ag) Anti Glomerular Basement Membrane Experimental Autoimmune Glomerulonephritis Enzyme-Linked Immunosorbent Assay (ELISA) Human Embryonic Kidney (HEK) Ig-Immunoglobulin (IgG IgA) IgAN-IgA nephropathy
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Mode stability analysis in the beam-wave interaction process for a three-gap Hughes-type coupled cavity chain 被引量:2
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作者 罗积润 崔健 +1 位作者 朱敏 郭炜 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第6期580-587,共8页
Based on space-charge wave theory, the formulae of the beam-wave coupling coefficient and the beam-loaded conductance are given for the beam-wave interaction in an N-gap Hughes-type coupled cavity chain. The ratio of ... Based on space-charge wave theory, the formulae of the beam-wave coupling coefficient and the beam-loaded conductance are given for the beam-wave interaction in an N-gap Hughes-type coupled cavity chain. The ratio of the nonbeam-loaded quality factor of the coupled cavity chain to the beam quality factor is used to determine the stability of the beam-wave interaction. As an example, the stabilities of the beam-wave interaction in a three-gap Hughes-type coupled cavity chain are discussed with the formulae and the CST code for the operations of the 2π, π, and π/2 modes, respectively. The results show that stable operation of the 2π, π, and π/2 modes may all be realized in an extended-interaction klystron with the three-gap Hughes-type coupled cavity chain. 展开更多
关键词 three-gap Hughes-type coupled cavity chain coupling coefficient beam-loaded conductance beam quality factor stability
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SYNTHESIS AND CHARACTERIZATION OF AZO TYPE SIDE CHAIN LIQUID CRYSTALLINE POLYSILOXANE
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作者 张淑媛 毕思伟 +1 位作者 谢萍 张榕本 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1991年第3期195-202,共8页
A novel side chain liquid crystalline polymer (SCLCP) combining the polysiloxane as main chain with azo-based mesogen moieties as side chain through a flexible spacer has been synthesized by the hydrosilylation reacti... A novel side chain liquid crystalline polymer (SCLCP) combining the polysiloxane as main chain with azo-based mesogen moieties as side chain through a flexible spacer has been synthesized by the hydrosilylation reaction using Cp_2PtCl_2 as catalyst. The phase transition behavior of both side chain monomer (AZO-C_6C_(11))and polymer (P-AZO-C_6C_(11))has been characterized via combination of hot-stage polarized microscope, DSC and X-ray diffraction methods (including temperature-variation and quenching techniques). As normal, the transition process included K→S→N→I. Some pretransition features have been observed. 展开更多
关键词 Liquid crystalline polysiloxane Azo-type side chain
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Influence of injection of Chinese botulinum toxin type A on the histomorphology and myosin heavy chain composition of rat gastrocnemius muscles 被引量:2
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作者 Bin HONG Min CHEN Xing-yue HU 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2013年第11期983-992,共10页
Background and objective:Botulinum toxin type A(BoNT/A)is a metalloprotease that blocks synaptic transmission via the cleavage of a synaptosomal-associated protein of 25 kDa(SNAP-25).It has gained widespread use as a ... Background and objective:Botulinum toxin type A(BoNT/A)is a metalloprotease that blocks synaptic transmission via the cleavage of a synaptosomal-associated protein of 25 kDa(SNAP-25).It has gained widespread use as a treatment for cerebral palsy and skeletal muscle hypertrophy.In China,Chinese botulinum toxin type A(CBTX-A),a type of BoNT/A,is in widespread clinical use.However,the changes in the morphological and biochemical properties of treated muscles and in remote muscles from the CBTX-A injection site are relatively unknown.Therefore,we investigated the changes in histomorphology and myosin heavy chain(MyHC)isoform composition and distribution in rat gastrocnemius muscles after intramuscular injection of CBTX-A.Methods:The weakness of the injected muscles was assessed periodically to identify their functional deficiency.Muscle slices were stained with hematoxylin-eosin(HE)and adenosine triphosphatase(ATPase).MyHC isoform composition was analyzed by sodium dodecyl sulfatepolyacrylamide gel electrophoresis(SDS-PAGE)to uncover changes in morphological and biochemical properties.Results:Our findings demonstrate that following injection of CBTX-A 5 U into rat gastrocnemius muscles,shifts in MyHC isoform composition emerged on the third day after injection and peaked in the fourth week.The composition remained distinctly different from that of the control group after the twelfth week.More specifically,there was a decrease in the proportion of the type IIb isoform and an increase in the proportions of type IIx,type IIa,and type I isoforms.Conclusions:Data revealed that CBTX-A led to a shift in MyHC composition towards slower isoforms and that the MyHC composition remained far from normal six months after a single injection.However,no noticeable remote muscle weakness was induced. 展开更多
关键词 Botulinum toxin type A(BoNT/A) Myosin heavy chain Chemodenervation Remote effect
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Epoxy-Based Chain Extenders in Polylactic Acid (PLA): A Comprehensive Review of Structure, Performance, and Challenges 被引量:1
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作者 Hao Duan Xiaoyan Shang +3 位作者 Xihao Wu Liuliu Ma Chen Xing Jun Zhu 《Journal of Materials Science and Chemical Engineering》 2025年第1期20-44,共25页
Amid the escalating plastic pollution issue, the development of biodegradable and recyclable polymeric materials has become a focus within the scientific community. Chain extenders, which are an important class of com... Amid the escalating plastic pollution issue, the development of biodegradable and recyclable polymeric materials has become a focus within the scientific community. Chain extenders, which are an important class of compounds, facilitate the elongation of polymer chains through reactive functional groups, thereby enhancing the performance of the materials. Epoxy-based chain extenders, due to their cost-effectiveness, low toxicity, high reaction efficiency, and effective reactivity with hydroxyl and carboxyl groups, have emerged as a promising class of chain extenders. This manuscript comprehensively elaborates on the varieties, structural characteristics, and performance of chain extenders, the challenges they face, and the methods for their modification. Special emphasis is placed on the application of epoxy-based chain extenders in biodegradable polymers, such as polylactic acid (PLA), and their subsequent influence on the structural and performance properties of these materials. 展开更多
关键词 chain Extender Epoxy type GMA BIODEGRADABLE PLA RECYCLE
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Type Synthesis of Fully-Decoupled 3R2T Parallel Mechanisms Based on Driven-Chain Principle
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作者 周辉 陈海 +2 位作者 秦友蕾 葛姝翌 曹毅 《Journal of Donghua University(English Edition)》 EI CAS 2017年第3期415-423,共9页
To avoid the existence of nonlinear and strong coupling in parallel mechanisms,it is necessary to address special care to the type synthesis of mechanisms,especially for the type synthesis of fully-decoupled parallel ... To avoid the existence of nonlinear and strong coupling in parallel mechanisms,it is necessary to address special care to the type synthesis of mechanisms,especially for the type synthesis of fully-decoupled parallel mechanisms. Based on the screw theory and the driven-chain principle,a methodology of structural synthesis for fully-decoupled three-rotational( 3R) and two-translational( 2T)parallel mechanisms was proposed by analyzing the characteristics of the input-output relations for fully-decoupled parallel mechanisms.Firstly,according to the desired kinematic characteristics of fullydecoupled parallel mechanisms,a method was presented by virtue of screw theory to synthesize the desired forms for both the direct and the inverse Jacobian matrices. Secondly,according to the feature of the direct and the inverse Jacobian matrices,the effective screws,the actuated screws and the mobile un-actuated screws of each leg were established based on the reciprocal screw theory and all possible topology structures fulfilling the requirements were obtained.Finally,the desired fully-decoupled parallel mechanisms could be synthesized by using the structural synthesis rule and structural synthesis of fully-decoupled 3R2 T parallel mechanisms could be obtained exploiting the abovementioned methodology. Furthermore,the Jacobian matrix of a synthesized 3R2 T parallel mechanism was deduced to demonstrate the decoupling feature of the parallel mechanism,which also validated the correctness of the methodology of the type synthesis for fully-decoupled 3R2 T parallel mechanisms. 展开更多
关键词 desired kinematic decoupling inverse translational matrices topology Jacobian reciprocal rotation
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链勺式单勺双型孔花生双粒精量排种器设计与试验
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作者 刘龙 刘道奇 +4 位作者 孙千涛 钱凯 王东伟 孙文喜 李秀杰 《农机化研究》 北大核心 2026年第5期57-64,共8页
针对花生机械化播种过程中因种子尺寸差异较大造成重播、漏播的问题,设计了一种链勺式单勺双型孔花生双粒精量排种器。采用种勺型孔对称布置的方式,实现单个种勺双粒取种、投种的功能;同时,在种勺上增加了倾斜清种结构,使进入清种区的... 针对花生机械化播种过程中因种子尺寸差异较大造成重播、漏播的问题,设计了一种链勺式单勺双型孔花生双粒精量排种器。采用种勺型孔对称布置的方式,实现单个种勺双粒取种、投种的功能;同时,在种勺上增加了倾斜清种结构,使进入清种区的待清种种子脱离种勺后能快速向两侧滑落,回流至取种区,降低了排种器重播率。结合花生种子的实际尺寸,确定了种勺的关键结构参数:种勺型孔长度为17 mm、有效深度为11 mm、型孔宽度为16 mm、托种长度为35 mm;种勺整体的长、宽、高分别为48、38、48 mm。利用单因素试验对影响排种器作业性能的关键作业参数进行了台架试验,确定了取种倾角、清种倾角和作业速度取值范围分别为60°~80°、-10°~0°、1.5~2.5 km/h。采用二次回归正交旋转组合试验和多目标优化方法,得到了各因素的最优组合,并对优化后的作业参数进行验证,得到取种倾角为70.65°、清种倾角为-7.06°、作业速度为1.86 km/h时,排种合格指数为93.53%,能够满足花生播种的农艺要求。 展开更多
关键词 排种器 链勺式 种勺 响应面分析 花生
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一类离散时间的Phase-Type分布的逆问题
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作者 聂盼红 刘力维 《南京理工大学学报》 EI CAS CSCD 北大核心 2004年第5期557-560,共4页
该文从条件分布向量序列出发研究离散时间的Phase Type分布的逆问题。利用矩阵分析的方法 ,在已知Markov链首达时间的条件分布向量序列的前提下 。
关键词 马尔可夫链 Phase-type分布 首达时间
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住宅车库电机驱动链条式立体机械车位施工技术和经济效益分析
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作者 杨爽 《工程质量》 2026年第1期101-105,共5页
住宅小区地下车库车位依据规划要求或相关停车位配套标准进行配套车位数量计算,确定项目总的车位数量。综合考虑造价成本,配套车位数量刚好满足报建要求和实际功能要求即可,严格限制地下车库建筑面积。一般情况下,地下车库车位规划设计... 住宅小区地下车库车位依据规划要求或相关停车位配套标准进行配套车位数量计算,确定项目总的车位数量。综合考虑造价成本,配套车位数量刚好满足报建要求和实际功能要求即可,严格限制地下车库建筑面积。一般情况下,地下车库车位规划设计完成后很难再增加车位。在车位数量不能满足使用功能需要时,可采用在车库内设置电机驱动二层链条式立体机械车位。在立体机械停车位中,停车面积纵向延伸实现立体存放,可以有效提高容车率,高效利用空间,工程造价低于普通车位,而且出入库时间短。 展开更多
关键词 住宅 车库车位 链条式 机械车位 新增
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基于折线形路径规划的固沙草方格铺设机设计
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作者 任余艳 张凡 +5 位作者 高鸿永 姚鑫宇 周俐青 李欢 代百春 李碧雪 《林业机械与木工设备》 2026年第1期15-19,共5页
针对传统人工草方格沙障铺设效率低、成本高,以及现有铺设机械功能单一,仅能实现纵向直线铺设的问题,设计一种折线形沙障铺设机。该设备由电控装置、压草装置、输送装置及折线运动装置组成,核心功能在于草沙障的折线形铺设。机械结构上... 针对传统人工草方格沙障铺设效率低、成本高,以及现有铺设机械功能单一,仅能实现纵向直线铺设的问题,设计一种折线形沙障铺设机。该设备由电控装置、压草装置、输送装置及折线运动装置组成,核心功能在于草沙障的折线形铺设。机械结构上,采用滑槽-滚轮机构和双电机驱动,将牵引拖拉机的直线运动与压刀装置的横向往复运动相结合,合成了折线运动轨迹。控制系统基于STC80C52单片机开发,结合电磁传感器进行极限位置检测,实现了折线形轨迹生成及安全保护的自动化控制。草帘输送装置通过链式软连接与压草装置同步运动,确保草帘平稳输送与定位。通过机械-液压-电控多系统协同,显著提高了草沙障铺设的效率和自动化程度,降低了人力成本,并为满足多风向防风固沙需求提供了新的机械化解决方案。 展开更多
关键词 草沙障 折线形铺设 防沙 运动合成 链式软连接
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政府补贴下绿色供应链的竞争与合作研究——以新能源汽车为例
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作者 赵璇 李艳轩 《工业技术经济》 北大核心 2026年第2期43-55,共13页
在全球碳排放总量不断增加、绿色供应链各参与主体博弈关系错综复杂的背景下,研究如何在绿色供应链的竞争与合作并存格局中达成经济与环境效益的双赢,显得尤为关键。本文以新能源汽车为例,构建由供应商、制造商、消费者所组成的存在政... 在全球碳排放总量不断增加、绿色供应链各参与主体博弈关系错综复杂的背景下,研究如何在绿色供应链的竞争与合作并存格局中达成经济与环境效益的双赢,显得尤为关键。本文以新能源汽车为例,构建由供应商、制造商、消费者所组成的存在政府补贴的供应链模型,基于非合作-合作两型博弈理论,采用Stackelberg均衡与Shapley值的理论,揭示了绿色供应链间价格竞争与技术协同的交互机制。结果表明,政府提供的研发补贴与生产补贴对供应链的定价决策与利润分配具有明显的差异化影响。研发补贴虽然能有效提升绿色技术创新水平,但过高补贴存在边际效益递减效应;生产补贴则可稳定促进市场需求的持续扩张并提高供应链整体利润,因此政府应根据供应链的发展阶段合理设置补贴强度。 展开更多
关键词 非合作-合作两型博弈 政府补贴 绿色供应链 绿色技术创新 成本分担 新能源汽车 研发补贴 生产补贴
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多发性骨髓瘤患者血清MuC1、PINP、sFLC与临床分期、免疫分型的关系及对预后的预测价值
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作者 黄建霞 张国梁 +5 位作者 张菊山 王燕 吴庆 吴彬章 杜明虎 王玉霞 《实用医学杂志》 北大核心 2026年第3期504-510,共7页
目的探讨多发性骨髓瘤患者血清黏蛋白1(MuC1)、Ⅰ型前胶原氨基端延长肽(PINP)、游离轻链(sFLC)与临床分期、免疫分型的关系及对预后的预测价值。方法选取2020年7月至2024年5月武威市人民医院收治的220例多发性骨髓瘤患者作为病例组,均... 目的探讨多发性骨髓瘤患者血清黏蛋白1(MuC1)、Ⅰ型前胶原氨基端延长肽(PINP)、游离轻链(sFLC)与临床分期、免疫分型的关系及对预后的预测价值。方法选取2020年7月至2024年5月武威市人民医院收治的220例多发性骨髓瘤患者作为病例组,均根据国际分期系统(ISS)明确分为Ⅰ期26例、Ⅱ期82例和Ⅲ期112例;根据免疫分型明确分为免疫球蛋白(Ig)A型52例、IgG型96例、轻链型47例和非分泌型25例,同时根据治疗随访12个月内患者预后情况分为预后不良组(55例)和预后良好组(165例)。另按照1∶1比例选取同期健康体检者220名作为对照组。比较病例组、对照组临床资料及血清MuC1、PINP、s FLC(包括κ轻链sFLC-κ和λ轻链sFLC-λ),比较不同临床分期及不同免疫分型、不同预后患者血清MuC1、PINP、sFLC水平,并采用受试者工作特征(ROC)曲线分析血清MuC1、PINP、sFLC水平对多发性骨髓瘤患者预后的预测价值。结果病例组血清MuC1、sFLC-κ、sFLC-λ水平均高于对照组,血清PINP水平低于对照组(P<0.05)。Ⅲ期患者血清MuC1、sFLC-κ、sFLC-λ水平高于Ⅰ期、Ⅱ期患者,Ⅱ期患者高于Ⅰ期患者;Ⅲ期患者血清PINP水平低于Ⅰ期、Ⅱ期患者,Ⅱ期患者低于Ⅰ期患者(P<0.05)。IgG型患者血清MuC1、sFLC-κ、sFLC-λ水平均高于IgA型、轻链型、非分泌型患者,血清PINP水平均低于IgA型、轻链型、非分泌型患者(P<0.05)。预后不良组血清MuC1、sFLC-κ、sFLC-λ水平高于预后良好组,血清PINP水平低于预后良好组(P<0.05)。将预后不良纳入阳性,预后良好纳入阴性,血清MuC1、PINP、sFLC-κ、sFLC-λ及联合检测预测多发性骨髓瘤患者预后的曲线下面积(AUC)分别为0.765、0.665、0.753、0.710、0.914,诊断敏感度分别为72.73%、69.09%、72.73%、65.45%、87.27%,特异度分别为69.70%、62.42%、72.12%、73.33%、85.45%,其中联合检测的AUC最高(P<0.05)。结论血清MuC1、PINP、sFLC表达与多发性骨髓瘤的发生、发展及免疫分型有关,且对患者预后预测价值较高,而四者联合检测的预测价值最高。 展开更多
关键词 多发性骨髓瘤 黏蛋白1 Ⅰ型前胶原氨基端延长肽 游离轻链 临床分期 免疫分型 预后 预测价值
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枸杞多糖介导肠道菌群重塑改善2型糖尿病大鼠的糖脂异常
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作者 王京峰 冯硕 +1 位作者 曹炫 李晓琳 《中国组织工程研究》 北大核心 2026年第29期7592-7602,共11页
背景:枸杞多糖作为一种天然活性成分,具有降低血糖以及改善糖尿病相关症状的潜力。然而,从肠道菌群的角度,枸杞多糖对糖脂异常影响的潜在因素尚未完全阐明。目的:探究枸杞多糖在2型糖尿病中的作用及相关机制。方法:从18只8周龄雄性SD大... 背景:枸杞多糖作为一种天然活性成分,具有降低血糖以及改善糖尿病相关症状的潜力。然而,从肠道菌群的角度,枸杞多糖对糖脂异常影响的潜在因素尚未完全阐明。目的:探究枸杞多糖在2型糖尿病中的作用及相关机制。方法:从18只8周龄雄性SD大鼠中随机选取6只为空白对照组,其余12只大鼠给予高糖高脂饲料饲养8周+尾静脉单次注射1%链脲佐菌素溶液构建2型糖尿病模型,造模成功后随机分为模型对照组(n=6)和枸杞多糖组(n=6)。枸杞多糖组大鼠按照200 mg/(kg·d)的剂量灌胃枸杞多糖溶液,2 mL/次,1次/d,连续灌胃12周,收集大鼠血清及粪便。通过16S rDNA测序分析肠道菌群,采用α多样性、β多样性及主成分分析等方法表征菌群丰度与结构特征;采用液相色谱-质谱联用法检测短链脂肪酸水平;通过ELISA法检测糖脂代谢、胰岛素抵抗及炎症反应相关指标。结果与结论:①与模型对照组相比,枸杞多糖组高密度脂蛋白胆固醇水平升高,总胆固醇、三酰甘油和低密度脂蛋白胆固醇水平降低,说明枸杞多糖改善了2型糖尿病大鼠的脂质积累,并抑制体质量减轻;②与模型对照组相比,枸杞多糖组白细胞介素6、肿瘤坏死因子α以及血糖水平降低,胰岛素以及胰高血糖素样肽1水平升高,说明枸杞多糖有效抑制了炎症反应和胰岛素抵抗;③枸杞多糖显著改善了肠道菌群的组成,增加了Lachnospiraceae_NK4A136_group、Clostridia_UCG-014_unclassified、Monoglobus、Phascolarctobacterium、Candidatus_Saccharimonas、Desulfovibrionaceae unclassified以及Desulfovibrio丰度,减少了Muribaculaceae_unclassified和Enterorhabdus丰度;④枸杞多糖还显著提高了短链脂肪酸水平,并且Clostridia_UCG-014_unclassified、Candidatus_Saccharimonas和Muribaculaceae_unclassified可能参与调节丁酸的生成,以改善2型糖尿病大鼠的糖脂代谢,Lachnospiraceae_NK4A136_group、Monoglobus和Desulfovibrionaceae unclassified可能参与调节异丁酸的生成,以抑制胰岛素抵抗以及改善脂代谢;⑤枸杞多糖可通过增加Firmicutes_unclassified、Clostridia_UCG-014_unclassified、Intestinimona和Colidextribacter以及抑制Kineothrix的丰度来改善2型糖尿病大鼠的炎症反应。 展开更多
关键词 枸杞多糖 肠道菌群 2型糖尿病 短链脂肪酸 糖脂代谢 炎症
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Distributions of HLA-A and-B alleles and haplotypes in the Yi ethnic minority of Yunnan, China: relationship to other populations 被引量:2
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作者 Bo-feng ZHU Guang YANG +12 位作者 Chun-mei SHEN Hai-xia QIN Shun-zhi LIU Ya-jun DENG Shuan-liang FAN Li-bin DENG Feng CHEN Ping ZHANG Jie FANG Li-ping CHEN Hong-dan WANG Zhen-yuan WANG Rudolf LUCAS 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2010年第2期127-135,共9页
Objective: To investigate the distributions of human leukocyte antigen (HLA)-A and-B alleles and HLA-A-B haplotypes in the Yi ethnic minority of the Yunnan Province, situated in southwestern China. Methods: DNA typing... Objective: To investigate the distributions of human leukocyte antigen (HLA)-A and-B alleles and HLA-A-B haplotypes in the Yi ethnic minority of the Yunnan Province, situated in southwestern China. Methods: DNA typing for HLA-A and-B loci was performed using the polymerase chain reaction-sequence-based typing (PCR-SBT) method on 114 randomly selected healthy individuals of the Yi population. The allelic frequencies of HLA-A and-B loci were calculated by direct counting and HLA-A-B haplotypes were estimated using the expectation maximization algorithm. Results: A total of 17 HLA-A and 38 HLA-B alleles were found in the Yi population. The most frequent alleles were A2402 (32.46%), A1101 (26.32%), and A0203 (10.09%) at the HLA-A locus and B4601 (12.28%), B1525 (10.09%), B4001 (8.77%), and B3802 (7.89%) at the HLA-B locus. The predominant HLA-A-B haplotypes were A2402-B1525 (7.86%) and A0203-B3802 (5.64%), followed by A1101-B4001 (4.69%). Phylogenetic analysis indicates that the Yi population in the Honghe, Yunnan Province of China basically belongs to groups of southeastern Asian origin, but shares some characteristics with northeastern Asian groups. Conclusion: The present study may add to the understanding of HLA polymorphism in the Yi ethnic group that was poorly defined previously, and provide useful information for bone marrow transplantation, anthropological research, and forensic sciences as well as for disease-association studies. 展开更多
关键词 Yi ethnic minority Human leukocyte antigen (HLA)-A HLA-B ALLELE HAPLOtype Polymerase chain reaction-sequence-based typing (PCR-SBT)
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Liquid crystal character controlled by complementary discotic molecules mixtures: Columnar stacking type and mesophase temperature range 被引量:2
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作者 Yan Li Ming-Guang Li +4 位作者 Ya-Jun Su Jian-Gang Liu Yan-Chun Han Shi-Jun Zheng Li-Xiang Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2016年第3期475-480,共6页
In this work, the mesophase properties were tuned via mixing two discotic molecules with structural complementarity. Compared with the liquid crystalline hexakis(n-hexyloxy)triphenylene(H6TP)materials(columnar he... In this work, the mesophase properties were tuned via mixing two discotic molecules with structural complementarity. Compared with the liquid crystalline hexakis(n-hexyloxy)triphenylene(H6TP)materials(columnar hexagonal phase from 53 ℃ to 91 ℃), mesophase types as well as phase transition temperatures varied with the introduction of crystalline hexaazatriphenylene derivative(PBH)molecules. The introduction of less than 33% amount of PBH disrupted the columnar hexagonal phase formed by H6 TP remarkably, followed by the decreased clearing temperatures of liquid crystals. As the PBH amount was further increased, the destroyed columnar hexagonal phase was turned into the columnar rectangular phase, in which H6 TP and PBH molecules together formed the columnar mesophase. The formation of new mesophase contributed to the enlarged mesophase temperature(from44 ℃ to 144 ℃). We speculated that the alkyl chains interaction induced by the PBH component competed with the strong p–p stacking between H6 TP molecules, thus altering the liquid crystalline properties including mesophase types and phase transition temperatures. 展开更多
关键词 Alkyl chains packing Mesophase type Liquid crystals Phase transitions Mixture
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