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Perirenal space blocking restores gastrointestinal function in patients with severe acute pancreatitis 被引量:9
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作者 Jun-Jun Sun Zhi-Jie Chu +7 位作者 Wei-Feng Liu Shi-Fang Qi Yan-Hui Yang Peng-Lei Ge Xiao-Hui Zhang Wen-Sheng Li Cheng Yang Yu-Ming Zhang 《World Journal of Gastroenterology》 SCIE CAS 2013年第46期8752-8757,共6页
AIM:To investigate effects of perirenal space blocking(PSB)on gastrointestinal function in patients with severe acute pancreatitis(SAP).METHODS:Forty patients with SAP were randomly allocated to receive PSB or no PSB(... AIM:To investigate effects of perirenal space blocking(PSB)on gastrointestinal function in patients with severe acute pancreatitis(SAP).METHODS:Forty patients with SAP were randomly allocated to receive PSB or no PSB(NPSB).All the SAP patients received specialized medical therapy(SMT).Patients in the PSB group received PSB+SMT when hospitalized and after diagnosis,whereas patients in the NPSB group only received SMT.A modifed gastrointestinal failure(GIF)scoring system was used to assess the gastrointestinal function in SAP patients after admission.Pain severity(visual analog scale,0 to100)was monitored every 24 h for 72 h.RESULTS:Modified GIF score decreased in both groups during the 10-d study period.The median score decrease was initially significantly greater in the PSB group than in the NPSB group after PSB was per-formed.During the 72-h study period,pain intensity decreased in both groups.The median pain decrease was significantly greater in the PSB group than in the NPSB group at single time points.Patients in the PSB group had significantly lower incidences of hospital mortality,multiple organ dysfunction syndrome,systemic inflammatory response syndrome,and pancreatic infection,and stayed in the intensive care unit for a shorter duration.However,no difference in terms of operation incidence was found between the two groups.CONCLUSION:PSB could ameliorate gastrointestinal dysfunction or failure during the early stage of SAP.Moreover,PSB administration could improve prognosis and decrease the mortality of SAP patients. 展开更多
关键词 Perirenal space blockING THERAPEUTICS SEVERE acute PANCREATITIS GASTROINTESTINAL function PROGNOSIS
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Stellate ganglion block reduces inflammation and improves neurological function in diabetic rats during ischemic stroke 被引量:15
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作者 Ting-Ting Li Qiang Wan +5 位作者 Xin Zhang Yuan Xiao Li-Ying Sun Yu-Rong Zhang Xiang-Nan Liu Wan-Chao Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2022年第9期1991-1997,共7页
Diabetes mellitus is an independent risk factor for ischemic stroke.Both diabetes mellitus and stroke are linked to systemic inflammation that aggravates patient outcomes.Stellate ganglion block can effectively regula... Diabetes mellitus is an independent risk factor for ischemic stroke.Both diabetes mellitus and stroke are linked to systemic inflammation that aggravates patient outcomes.Stellate ganglion block can effectively regulate the inflammatory response.Therefore,it is hypothesized that stellate ganglion block could be a potential therapy for ischemic stroke in diabetic subjects.In this study,we induced diabetes mellitus in rats by feeding them a high-fat diet for 4 successive weeks.The left middle cerebral artery was occluded to establish models of ischemic stroke in diabetic rats.Subsequently,we performed left stellate ganglion block with 1%lidocaine using the percutaneous posterior approach 15 minutes before reperfusion and again 20 and 44 hours after reperfusion.Our results showed that stellate ganglion block did not decrease the blood glucose level in diabetic rats with diabetes mellitus but did reduce the cerebral infarct volume and the cerebral water content.It also improved the recovery of neurological function,increased 28-day survival rate,inhibited Toll like receptor 4/nuclear factor kappa B signaling pathway and reduced inflammatory response in the plasma of rats.However,injection of Toll like receptor 4 agonist lipopolysaccharide 5 minutes before stellate ganglion block inhibited the effect of stellate ganglion block,whereas injection of Toll like receptor 4 inhibitor TAK242 had no such effect.We also found that stellate ganglion block performed at night had no positive effect on diabetic ischemic stroke.These findings suggest that stellate ganglion block is a potential therapy for diabetic ischemic stroke and that it may be mediated through the Toll like receptor 4/nuclear factor kappa B signaling pathway.We also found that the therapeutic effect of stellate ganglion block is affected by circadian rhythm. 展开更多
关键词 circadian rhythms diabetes mellitus INFLAMMATION ischemic stroke long-term prognosis neurological function NEURON nuclear factor kappa B stellate ganglion block Toll like receptor 4
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基于FBS和AHP的AI大模型辅助无障碍智能轮椅设计研究 被引量:3
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作者 王永东 孙凌云 杨先艺 《包装工程》 北大核心 2025年第4期172-182,共11页
目的旨在探索Co-Design视域下,针对行动障碍者,设计一款无障碍智能轮椅产品。方法该研究整体上利用FBS设计模型的宏观思维,确立了以用户的行为和功能需求映射产品结构的研究思路,并利用AHP层次分析理论寻找用户需求和产品功能要素的最优... 目的旨在探索Co-Design视域下,针对行动障碍者,设计一款无障碍智能轮椅产品。方法该研究整体上利用FBS设计模型的宏观思维,确立了以用户的行为和功能需求映射产品结构的研究思路,并利用AHP层次分析理论寻找用户需求和产品功能要素的最优解,进而发现针对特定群体的无障碍轮椅设计痛点,最后通过将设计痛点输入AI大模型,进行迭代设计和方案优化,直至产生最优的设计方案。结论根据对用户群体需求指标的AHP层次分析,用户对轮椅安全性和舒适性的需求最为强烈,这从根本上确定了用户潜在的行为特征,以及用户对无障碍轮椅设计的功能需求,进而从整体上确定了该无障碍轮椅的产品结构与功能。 展开更多
关键词 fbS模型 AHP层次分析 用户需求 功能映射
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Macroscopic Regulation of Hierarchical Nanostructures in Liquid-crystalline Block Copolymers towards Functional Materials 被引量:3
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作者 Feng Cai Yu-Xuan Chen +1 位作者 Wen-Zhong Wang Hai-Feng Yu 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2021年第4期397-416,I0004,共21页
The great potential of liquid-crystalline block copolymers(LCBCs)containing photoresponsive mesogens toward novel applications in photonics and nanotechnology has been attracting increasing attention,due to the combin... The great potential of liquid-crystalline block copolymers(LCBCs)containing photoresponsive mesogens toward novel applications in photonics and nanotechnology has been attracting increasing attention,due to the combination of the inherent property of microphase separation of block copolymers and the hierarchically-assembled structures of liquid-crystalline polymers(LCPs).The periodically ordered nanostructures in bulk film of LCBCs can be acquired by supramolecular cooperative motion,derived from the interaction between liquid-crystalline elastic deformation and microphase separation,which are able to improve physical properties of polymer film toward advanced functional applications.Moreover,various micro/nano-patterned structures have been fabricated via light manipulation of photoresponsive LCBCs with good reproducibility and mass production.Thanks to recent developments in synthesis and polymerization techniques,diverse azobenzene-containing LCBCs have been designed,resulting in the creation of a wide variety of novel functions.This review illustrates recent progresses in macroscopic regulation of hierarchical nanostructures in LCBCs towards functional materials.The existing challenges are also discussed,showing perspectives for future studies. 展开更多
关键词 Liquid-crystalline block copolymers Microphase separation Hierarchical nanostructures functional materials
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Greatly enhanced corrosion/wear resistances of epoxy coating for Mg alloy through a synergistic effect between functionalized graphene and insulated blocking layer 被引量:3
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作者 Z.Y.Xue X.J.Li +3 位作者 J.H.Chu M.M.Li D.N.Zou L.B.Tong 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期332-344,共13页
The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification proc... The poor corrosion and wear resistances of Mg alloys seriously limit their potential applications in various industries.The conventional epoxy coating easily forms many intrinsic defects during the solidification process,which cannot provide sufficient protection.In the current study,we design a double-layer epoxy composite coating on Mg alloy with enhanced anti-corrosion/wear properties,via the spin-assisted assembly technique.The outer layer is functionalized graphene(FG)in waterborne epoxy resin(WEP)and the inner layer is Ce-based conversion(Ce)film.The FG sheets can be homogeneously dispersed within the epoxy matrix to fill the intrinsic defects and improve the barrier capability.The Ce film connects the outer layer with the substrate,showing the transition effect.The corrosion rate of Ce/WEP/FG composite coating is 2131 times lower than that of bare Mg alloy,and the wear rate is decreased by~90%.The improved corrosion resistance is attributed to the labyrinth effect(hindering the penetration of corrosive medium)and the obstruction of galvanic coupling behavior.The synergistic effect derived from the FG sheet and blocking layer exhibits great potential in realizing the improvement of multi-functional integration,which will open up a new avenue for the development of novel composite protection coatings of Mg alloys. 展开更多
关键词 Mg alloy functionalized graphene Epoxy coating Corrosion/wear resistance blocking layer
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Block copolymer electrolyte with adjustable functional units for solid polymer lithium metal battery 被引量:3
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作者 Zhiyuan Lin Xianwei Guo +3 位作者 Yubo Yang Mingxue Tang Qi Wei Haijun Yu 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第1期67-74,I0003,共9页
Solid polymer electrolytes have been considered as the promising candidates to improve the safety and stability of high-energy lithium metal batteries.However,the practical applications of solid polymer electrolytes a... Solid polymer electrolytes have been considered as the promising candidates to improve the safety and stability of high-energy lithium metal batteries.However,the practical applications of solid polymer electrolytes are still limited by the low ionic conductivity,poor interfacial contact with electrodes,narrow electrochemical window and weak mechanical strength.Here,a series of novel block copolymer electrolytes with three-dimensional networks are designed by cross-linked copolymerization of the polyethylene glycol soft segments and hexamethylene diisocyanate trimer hard segments.Their ionic migration performances and interface compatibilities with Li metal anode have been optimized delicately by tailoring the ratio of these functional units.The optimized block copolymer electrolyte has shown an amorphous crystalline structure,a high ionic conductivity of ~5.7×10^(-4)S cm^(-1),high lithium ion transference number(~0.49),wide electrochemical window up to ~4.65 V(vs.Li+/Li) and favorable mechanical strength at 55℃.Furthermore,the enhanced interface compatibility can well support the normal operations of lithium metal batteries using both LiFePO4 and LiNi0.8Co0.15Al0.05O2 cathodes.This study not only paves a new way to develop solid polymer electrolyte with optimizing functional units,but also provides a polymer electrolyte design strategy for the application demand of lithium metal battery. 展开更多
关键词 block copolymer electrolyte functional units Ionic migration performance Interface compatibility Lithium metal battery
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Scattering Function and Spinodal Transition of Linear and Nonlinear Block Copolymers Based on a Unified Molecular Model 被引量:2
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作者 Weichao Shi 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2021年第6期779-788,I0009,共11页
This work uses a block copolymer architecture[(A′B)nA2]m to unify the scattering function and spinodal transition of typical AB-type block copolymers.The key roles of block number,junction points and asymmetry ratios... This work uses a block copolymer architecture[(A′B)nA2]m to unify the scattering function and spinodal transition of typical AB-type block copolymers.The key roles of block number,junction points and asymmetry ratios of block length are(1)to determine the form factor of each block copolymer at the molecular scale;(2)to affect the entropy loss across the spinodal transition and may result in deflection of spinodal curves.The common features are validated in typical linear and nonlinear block copolymers,including AB diblock,asymmetric A′BA triblock,miktoarm stars of ABn,AnBn,(AB)n,(A′B)nA,A′BAm,and multi-graft combs of(BnA2)m and[(A′B)nA2]m.The explicit scattering functions and form factors of various block copolymers can be directly applied in radiation experiments(i.e.neutron or X-ray scattering)to unravel the effect of molecular architecture in solution and microphase separation in disordered melt.The molecular model used in this study is also helpful to guide the chemical synthesis to explore more potentially interesting block copolymers. 展开更多
关键词 Scattering function Form factor Spinodal transition Molecular structure block copolymer
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A Parallel ATPG Algorithm Based on Big Function Block 被引量:1
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作者 Zhide Zeng Pengxia Liu 《湖南大学学报(自然科学版)》 EI CAS CSCD 2000年第S2期17-22,共6页
The paper presents a parallel ATPG algorithm - PTGBP, which aims at decreasing the complexity of the ATPG by partitioning circuit under test (CUT) to big function blocks (BFB) and processing them parallelly. PTGBP ado... The paper presents a parallel ATPG algorithm - PTGBP, which aims at decreasing the complexity of the ATPG by partitioning circuit under test (CUT) to big function blocks (BFB) and processing them parallelly. PTGBP adopts hybrid circuit mode and hybrid fault model, and organizes the parallel course in term of master/slave mode. Master processor loads the whole netlist of CUT based on BFB, every slave processor loads logic level (gate/function block/basic logic units) netlist of a BFB. Test generation (TG) uses BFB input/output s-a-0/s-a-1 fault model; fault simulation uses logic level single stuck fault model. Master controls the PTGBP’s running course and ensures the correctness of its running result; slaves provide the results of fault sensitization compatible computation and fault simulation to master parallelly. PTGBP algorithm is under implementation. 展开更多
关键词 parallel ATPG big function block register-transfer level
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Numerical Solution of Two-Dimensional Nonlinear Stochastic Ito-Volterra Integral Equations by Applying Block Pulse Functions 被引量:2
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作者 Guo Jiang Xiaoyan Sang +1 位作者 Jieheng Wu Biwen Li 《Advances in Pure Mathematics》 2019年第2期53-66,共14页
This paper investigates the numerical solution of two-dimensional nonlinear stochastic It&#244;-Volterra integral equations based on block pulse functions. The nonlinear stochastic integral equation is transformed... This paper investigates the numerical solution of two-dimensional nonlinear stochastic It&#244;-Volterra integral equations based on block pulse functions. The nonlinear stochastic integral equation is transformed into a set of algebraic equations by operational matrix of block pulse functions. Then, we give error analysis and prove that the rate of convergence of this method is efficient. Lastly, a numerical example is given to confirm the method. 展开更多
关键词 block Pulse functions Integration Operational Matrix Stochastic It?-Volterra Integral Equations
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TDS-1 GNSS reflectometry wind geophysical model function response to GPS block types 被引量:1
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作者 Fade Chen Xiaohong Zhang +3 位作者 Fei Guo Jiazhu Zheng Yang Nan Mohamed Freeshah 《Geo-Spatial Information Science》 SCIE EI CSCD 2022年第2期312-324,共13页
This paper presents the TDS-1 GNSS reflectometry wind Geophysical Model Function(GMF)response to GPS block types.The observables were extracted from Delay Doppler Maps(DDMs)after taking the receiver antenna gains effe... This paper presents the TDS-1 GNSS reflectometry wind Geophysical Model Function(GMF)response to GPS block types.The observables were extracted from Delay Doppler Maps(DDMs)after taking the receiver antenna gains effects and GNSS-R geometry effects into account.Since the DDM is affected by GPS EffectiveIsotropic Radiated Power(EIRP),we first investigate the sensitivity of observables to the GPS block.Additionally,the observables at high SNRs are more sensitive to wind speed,but the spatial coverage at high signal to noise ratios(SNRs)is lower,while DDMs at low SNRs have the opposite characteristics.To balance the accuracy and spatial coverage,the DDM datasets are divided into two parts:high SNR(>0 dB)and low SNR(>−10 dB and≤0 dB)to develop wind GMF.Then,the influences of GPS block on wind speed retrieval both at high and low SNR is analyzed.Results show that the block types have impacts on wind GMF and the use of a prior GPS block can contribute to a better wind speed retrieval both at high and low SNR.Compared with ASCAT,the Root Mean Square Error(RMSE)value of wind speed retrieval at high and low SNR are 2.19 m/s and 3.13 m/s,respectively,when all TDS data are processed without distinguishing GPS block types.However,if the TDS data are separately processed and used to develop wind GMF through different blocks,both the accuracy and correlation coefficient can be improved to some extent.Finally,the influence of significant height of the swell(Hs)on SNR observables is analyzed,and it is demonstrated that there is no obvious linear or nonlinear relationship between them. 展开更多
关键词 Global Navigation Satellite System-Reflectometry(GNSS-R) Delay-Doppler Map(DDM) wind speed Geophysical Model function(GMF) TechDemoSat-1(TDS-1) GPS block
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安氏Ⅱ类错[牙合]畸形佩戴Twin-block矫治器时上颌骨的应力分布 被引量:1
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作者 李帅 刘桦 +3 位作者 商永慧 刘义琮 赵启航 刘文 《中国组织工程研究》 CAS 北大核心 2025年第5期881-887,共7页
背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨... 背景:Twin-block矫治器常用于安氏Ⅱ类错[牙合]畸形的矫治,其刺激下颌骨生长的作用机制已得到许多研究证实,但对上颌骨生长的影响尚不清楚。目的:通过有限元法分析安氏Ⅱ类错[牙合]畸形患者佩戴Twin-block矫治器时上颌骨复合体、周围骨缝及上颌牙列的应力分布。方法:选择在山东省康复大学青岛医院/青岛市市立医院口腔正畸科进行正畸治疗的安氏Ⅱ类错[牙合]畸形患者1例,测量患者佩戴Twin-block矫治器时的咬合力数据,采集其锥形束CT数据,建立包含上颌骨复合体、周边各骨缝、Twin-block矫治器及上颌牙列在内的有限元模型,通过ABAQUS软件模拟患者戴入Twin-block时上颌骨、骨缝及上颌牙列的应力分布与位移。结果与结论:①上颌前牙受到的等效应力明显小于后牙,两侧牙齿的最大等效应力分别为4.7975 MPa和8.7161 MPa,均位于第一前磨牙处;最大位移呈现在两侧上颌切牙处,分别为0.0805 mm和0.0810 mm;②骨缝的最大等效应力为1.284 MPa,主要集中在两侧翼腭缝及额颌缝,其余骨缝受力情况几乎无差异;骨缝的最大位移为0.07 mm,其中翼腭缝的位移量最大,其次是额颌缝;③上颌骨复合体受到的最大等效应力为27.18 MPa,主要集中在上颌骨前面梨状孔两侧、鼻额缝周边及颚骨后部翼腭缝附近;上颌骨的最大位移值为0.07 mm,主要集中于上颌牙槽骨;④结果显示,咬合力通过Twin-block矫治器作用于上颌骨复合体,导致上颌骨顺时针旋转、牙合平面变陡,应采取相应措施补偿这种趋势,例如建牙合过程中考虑上颌磨牙伸长、下颌磨牙压低,不仅能够将牙合平面整平,同时有利于下颌前伸,这将进一步提高Ⅱ类错[牙合]正畸治疗效果。 展开更多
关键词 错牙合畸形 组织构建 骨组织工程 TWIN-block矫治器 功能矫治 有限元分析
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Synthesis And Properties Of Functional Ultra-High Molecular Weight Transparent Styrene-Butadiene Block Copolymer
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作者 GONG Guang-bi1, ZHAO Xu-tao1, WANG Gui-lun2 1.Petrochemical Research Institute of Lanzhou Petrochemical Corporation, PetroChina, Lanzhou 730060, China 2.Chemical & Marketing Company of PetroChina Company Limited, Beijing 100011, China 《合成化学》 CAS CSCD 2004年第z1期57-57,共1页
关键词 ANIONIC polymerization Styrene-butadiene block copolymer Coupling agent MATHEMATICAL model functionAL group
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A convenient,highly-efficient method for preparation of hydroxyl-terminated isotactic poly(propylene) and functional di-block copolymer 被引量:5
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作者 Ya-Nan Ye Pei-Yuan Li +3 位作者 Yong-Gang Shangguan Zhi-Sheng Fu Qiang Zheng Zhi-Qiang Fan 《Chinese Chemical Letters》 SCIE CAS CSCD 2014年第4期596-600,共5页
Both terminated functional isotactic polypropylene (iPP) and block copolymers containing iPP segment are desirable for commercial applications. This paper provides a convenient, highly-efficient method to prepare hy... Both terminated functional isotactic polypropylene (iPP) and block copolymers containing iPP segment are desirable for commercial applications. This paper provides a convenient, highly-efficient method to prepare hydroxyl-terminated isotactic polypropylene (iPP-t-OH) and functional di-block copolymer containing the iPP segment through a combination of coordination polymerization and coupling reaction. The coordination polymerization was catalyzed by TiCI4/MgCI2/AIEt3 catalyst system using ZnEt2 as chain transfer agent. Further, the Zn-terminated iPP was oxidized and subsequently hydrolyzed to provide iPP-t-OH. Soxhlet extraction and 13C NMR were used to calculate the isotacticity of iPP-t-OH. The degree of polymerization and the number of hydroxyl groups at the chain end of iPP-t-OH were measured by GPC and 1H NMR. Despite the high molecular weight and heterogeneous reaction, iPP-t-OH is effectively linked with PEG-t-NCO to produce di-block copolymers. DSC analysis of the di-block copolymer shows an obvious decrease in Tm and To, which indicated that PEG was successfully linked to the terminal end of iPP. 展开更多
关键词 Hydroxyl-terminated isotacticpoly(propylene) Di-block copolymer functionality Coupling reaction
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Pectoral Nerves (PECS) Block Is Effective for Motor Function Recovery in the Early Postoperative Period after Breast Cancer Surgery
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作者 Eiko Hara Hironobu Ueshima +1 位作者 Noriko Tanaka Hiroshi Otake 《Open Journal of Anesthesiology》 2017年第10期351-355,共5页
Background: Pectoral nerves (PECS) block has been reported to be effective for a perioperative analgesia for breast cancer surgery. In addition, we may consider that the PECS block is also effective for motor function... Background: Pectoral nerves (PECS) block has been reported to be effective for a perioperative analgesia for breast cancer surgery. In addition, we may consider that the PECS block is also effective for motor function in postoperative period. Therefore, we investigated the effect of PECS block for motor function in postoperative period. Methods: This study selected the patients performed the breast cancer surgery between April and September, 2015. The study surveyed the difficulty of movement of the upper limbs at postoperative day 5 (D5) and postoperative month 6 (M6) by performing telephone survey. We counted the number of patients who complained of the difficulty of movement of the upper limbs. All results were compared using the chi- squared test. P < 0.05 was considered statistically significant. Results: 93 patients received only general anesthesia (G group). 85 patients received PECS block with general anesthesia (P group). The number of the P group at D5 was 2 patients. On the other hand, the number of the G group was 15 patients (P = 0.042). In the same way, the number of the P group M6 was no patient. On the other hand, the number of the G group was 10 patients (P = 0.043). Conclusion: A PECS block is effective for motor function recovery in the early postoperative period after breast cancer surgery. 展开更多
关键词 BREAST Cancer Pectoral NERVES block MOTOR function
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The Lithospheric Structure in the South China Block from Receiver Function: Implications for the Source of Mineral System
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作者 CHEN Changxin LV Qingtian +3 位作者 CHEN Ling SHI Danian YAN Jiayong AI Yinshuang 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2021年第S01期28-30,共3页
The South China block(SC),composed of Cathaysia(CA),Jiangnan Orogenic belt(JNB),and Yangtze block(YB),is one of the most important poly-metallic metallogenic provinces in the world(Zhang et al.,2013),containing of fou... The South China block(SC),composed of Cathaysia(CA),Jiangnan Orogenic belt(JNB),and Yangtze block(YB),is one of the most important poly-metallic metallogenic provinces in the world(Zhang et al.,2013),containing of four famous major Mesozoic metallogenic belts,involving the Middle-Lower Yangtze Fe-Cu-Au metallogenic belt(MYMB). 展开更多
关键词 receiver function South China block lithosphere structure mineral system sources material
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A New Black Box Analysis of Hash Functions Based on Block Ciphers
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作者 达林 多磊 +1 位作者 Matt Henricksen 李超 《Journal of Shanghai Jiaotong university(Science)》 EI 2008年第6期664-669,共6页
For the 64 most basic ways to construct a hash function H:{0,1} → {0,1}n from a block cipher E:{0,1}n × {0,1}n → {0,1}n, Black et al.provided a formal and quantitative treatment of the 64 constructions, and pro... For the 64 most basic ways to construct a hash function H:{0,1} → {0,1}n from a block cipher E:{0,1}n × {0,1}n → {0,1}n, Black et al.provided a formal and quantitative treatment of the 64 constructions, and proved that 20 schemes are collision resistant.This paper improves the upper and lower bounds and make contrast with a hash constructed from a random oracle.These 20 schemes have only one kind of collision resistance upper and lower bounds.In addition, we present new advantages for finding second preimages. 展开更多
关键词 hash functions block cipher Merkel Damagard construction black box model
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Derivation of Optimal Global Equalization Function with Variable Size Block Based Local Contrast Enhancement
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作者 Ralph Oyini Mbouna Young-joon HAN 《Journal of Measurement Science and Instrumentation》 CAS 2010年第4期334-337,共4页
A conventional global contrast enhancement is difficult to apply in various images because image quality and contrast enhancement are dependent on image characteristics largely. And a local contrast enhancement not on... A conventional global contrast enhancement is difficult to apply in various images because image quality and contrast enhancement are dependent on image characteristics largely. And a local contrast enhancement not only causes a washed-out effect, but also blocks. To solve these drawbacks, this paper derives an optimal global equalization function with variable size block based local contrast enhancement. The optimal equalization function makes it possible to get a good quality image through the global contrast enhancement. The variable size block segmentation is firstly exeoated using intensity differences as a measure of similarity. In the second step, the optimal global equalization function is obtained from the enhanced contrast image having variable size blocks. Conformed experiments have showed that the proposed algorithm produces a visually comfortable result image. 展开更多
关键词 global oontrast enhancement local contrast enhancement optimal equalization function block segmentation variable size block
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新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的疗效分析 被引量:1
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作者 丁盟 张薇 +5 位作者 沈群 陈玉成 张慧 葛非凡 杭梦月 吴建华 《上海口腔医学》 2025年第3期291-297,共7页
目的:评价一种新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的临床疗效。方法:选择年龄10~13岁的骨性Ⅱ类下颌骨后缩患者21例,使用一种新型固定式Twin-block矫治器进行功能矫形治疗,治疗前后拍摄全景片及头颅侧位片并进... 目的:评价一种新型固定式Twin-block矫治器治疗青春期骨性Ⅱ类错[牙合]畸形的临床疗效。方法:选择年龄10~13岁的骨性Ⅱ类下颌骨后缩患者21例,使用一种新型固定式Twin-block矫治器进行功能矫形治疗,治疗前后拍摄全景片及头颅侧位片并进行头影测量。结果:治疗过程中未出现矫治器松动、脱落,平均疗程为(11.42±1.78)个月。治疗前后矢状向测量指标中,下颌骨位置(SNB)、下颌骨综合长度(Co-Gn)、鼻唇角(Cm-Sn-UL)、髁突矢状向位置(Pcd-S)、下唇突度(LL-SnPg)显著增大(P<0.05);上下颌骨相对位置(ANB)、Y轴角(SGn/FH)、上前牙倾斜度(U1/SN)、颏唇沟深度(Si-LLPg')显著减小(P<0.05);上颌骨位置(SNA)、下颌后部位置(S Vert-Co)、下颌体长度(Go'-Me)、下前牙倾斜度(IMPA),上下中切牙角度(U1/L1)、上唇突度(UL-SnPg')的差异无统计学意义(P>0.05)。垂直向测量指标除后面高(S-Go')、上前牙垂直向距离(U1-PP)、平面角(SN/OP)、下颌高度(Ar-Go')、下颌支高度(Co-Go)显著增加外(P<0.05),下牙列垂直向位置(Ll-MP、L6-MP)、上后牙垂直向距离(U6-PP)、前面高(N-Me)、面高指数(S-Go'/N-Me)、下颌平面角(MP/SN)均无显著改变(P>0.05)。结论:新型固定式Twin-block矫治器可显著促进下颌骨生长改建,有效进行垂直向控制,内收前牙同时改善患者侧貌,临床疗效可靠。 展开更多
关键词 固定式Twin-block矫治器 骨性Ⅱ类错[牙合]畸形 功能矫治 垂直向控制
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Transfer function of FBS-3A feedback broadband seismometer
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作者 刘庆伟 庄灿涛 刘慧宁 《Acta Seismologica Sinica(English Edition)》 EI CSCD 2001年第1期82-90,118,共10页
FBS-3A feedback broadband seismometer has been widely utilized in observation networks up to now. Therefore, it is very important and practically meaningful for the application of this kind of sensor to fulfill some r... FBS-3A feedback broadband seismometer has been widely utilized in observation networks up to now. Therefore, it is very important and practically meaningful for the application of this kind of sensor to fulfill some relative research work about its transfer function and for the analysis to the data recorded and the further development of the seismometer. In this paper, from the viewpoint of achieving its working principle, method of systematic analysis is applied to deduce the transfer functions, including both the transfer function for calibration and that for measurement. Moreover, on the basis of that, the distribution of its zeroes and poles in a complex frequency domain is analyzed, which provides a convincing evidence to simplify this seismometer system from a high-order one to a two-order one. And the emulation of the frequency characteristics of FBS-3A is presented in this paper. On the whole, the aim of this article is to do some theoretical work about the earthquake observation sensor, and also to introduce the method of making systematic analysis in a complex frequency domain to the research and the development of the seismometers. 展开更多
关键词 fbS-3A seismometer feedback seismometer transfer function
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Effects of dexmedetomidine combined with ultrasound-guided nerve block on hemodynamics, immune function and cortisol levels in patients undergoing inguinal surgery
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作者 Qiang Cai Mei-Ling Gao +3 位作者 Bin Wang Ting-Ru Xue Qing Li Xing Zhao 《Journal of Hainan Medical University》 2018年第16期9-12,共4页
Objective:To investigate the effect of dexmedetomidine combined with ultrasound guided nerve block on the hemodynamics, immune function and cortisol level in the patients undergoing inguinal surgery.Methods:A total of... Objective:To investigate the effect of dexmedetomidine combined with ultrasound guided nerve block on the hemodynamics, immune function and cortisol level in the patients undergoing inguinal surgery.Methods:A total of 120 patients who underwent unilateral inguinal surgery in our hospital were randomly divided into control group and observation group, 60 cases in each group. The control group was induced by intravenous anesthesia with sufentanil. The observation group was given dexmedetomidine combined with ultrasound guided ilioinguinal/iliac hypogastric nerve block. Hemodynamics, immune function and cortisol levels were compared between the two groups before and after anesthesia induction. Results:After anesthesia, in surgical incision and recovery time, the levels of HR in the two groups were significantly lower than that before the anesthesia, and the levels of HR in the observation group were significantly lower than that in the control group. After anesthesia, in surgical incision and recovery time, the levels of CD3+, CD4+ and CD4+/CD8+ in the control group were significantly lower than that of the group before anesthesia. After anesthesia, the levels of CD3+, CD4+ and CD4+/CD8+ in the observation group were significantly lower than that of the group before anesthesia. In surgical incision and recovery time, there was no significant difference in the levels of CD3+, CD4+ and CD4+/CD8+ in the observation group before anesthesia. After anesthesia, in surgical incision and recovery time, the levels of CD3+, CD4+ and CD4+/CD8+ in the observation group were significantly higher than that of the control group. The levels of serum PI3K, ET -1, CRP and cortisol of the two groups were significantly higher than those before anesthesia, and the levels of PI3K, ET -1, CRP and cortisol in the serum of the patients in the observation group were significantly lower than those in the control group.Conclusion: The effect of dexmedetomidin combined with ultrasound guided nerve block anesthesia on the patients with inguinal surgery can effectively maintain the hemodynamic stability of the patients and have less influence on the immune function and the stress response. The security is higher. 展开更多
关键词 DEXMEDETOMIDINE ULTRASOUND-GUIDED nerve block INGUINAL region SURGERY HEMODYNAMICS Immune function CORTISOL
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