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    题名 作者 年代 出处 被引量
1Gut microbiota in autism and mood disorders显示文摘The hypothesis of an important role of gut microbiota in the maintenance of physiological state into the gastrointestinal(GI)system is supported by several studies that have shown a qualitative and quantitative alteration of the intestinal flora in a number of gastrointestinal and extra-gastrointestinal diseases.In the last few years,the importance of gut microbiota impairment in the etiopathogenesis of pathology such as autism,dementia and mood disorder,has been raised.The evidence of the inflammatory state alteration,highlighted in disorders such as schizophrenia,major depressive disorder and bipolar disorder,strongly recalls the microbiota alteration,highly suggesting an important role of the alteration of GI system also in neuropsychiatric disorders.Up to now,available evidences display that the impairment of gut microbiota plays a key role in the development of autism and mood disorders.The application of therapeutic modulators of gut microbiota to autism and mood disorders has been experienced only in experimental settings to date,with few but promising results.A deeper assessment of the role of gut microbiota in the development of autism spectrum disorder(ASD),as well as the advancement of the therapeutic armamentarium for the modulation of gut microbiota is warranted for a better management of ASD and mood disorders.Francesca Mangiola Gianluca Ianiro Francesco Franceschi Stefano Fagiuoli Giovanni Gasbarrini Antonio Gasbarrini 2016World Journal of Gastroenterology2016,22,1:23
2Current status and recent advances of liver transplantation from donation after cardiac death显示文摘The last decade saw increased organ donation activity from donors after cardiac death (DCD). This contributed to a signif icant proportion of transplant activity. Despite certain drawbacks, liver transplantation from DCD donors continues to supplement the donor pool on the backdrop of a severe organ shortage. Understanding the pathophysiology has provided the basis for modulation of DCD organs that has been proven to be effective outside liver transplantation but remains experimental in liver transplantation models. Research continues on how best to further increase the utility of DCD grafts. Most of the work has been carried out exploring the use of organ preservation using machine assisted perfusion. Both ex-situ and in-situ organ perfusion systems are tested in the liver transplantation setting with promising results. Additional techniques involved pharmacological manipulation of the donor, graft and the recipient. Ethical barriers and end-of-life care pathways are obstacles to widespread clinical application of some of the recent advances to practice. It is likely that some of the DCD offers are in fact probably 'prematurely' of-fered without ideal donor management or even prior to brain death being established. The absolute benef its of DCD exist only if this form of donation supplements the existing deceased donor pool; hence, it is worthwhile revisiting organ donation process enabling us to identify counter remedial measures.M Thamara PR Perera Simon R Bramhall 2011World Journal of Gastrointestinal Surgery2011,3,11:16
3Recent progress on ULF wave and its interactions with energetic particles in the inner magnetosphere显示文摘The global distribution properties of Ultra Low Frequency wave (ULF) in the inner magnetospgere and its interactions with energetic particles, such as the wave-particle resonance, modulation, and particle acceleration, are active topics in space physics research. These problems are fundamentally important issues to understand the energy transport from the solar wind into the magnetosphere. In this paper we briefly reviewed the recent research progress on ULF wave and its interactions with energetic particles in the inner magnetosphere; furthermore, we suggested some open questions for future study.Theodore A. FRITZ 2008Science China(Technological Sciences)2008,51,10:16
4Application of human umbilical cord blood-derived mesenchymal stem cells in disease models显示文摘Human umbilical cord blood-derived mesenchymal stem cells(hUCB-MSCs) are regarded as an alternative source of bone marrow-derived mesenchymal stem cells because collection of cord blood is less invasive than that of bone marrow.hUCB-MSCs have recently been studied for evaluation of their potential as a source of cell therapy.In this review,the general characteristics of hUCBMSCs and their therapeutic effects on various diseases in vitro and in vivo will be discussed.Ju-Yeon Kim Hong Bae Jeon Yoon Sun Yang Wonil Oh Jong Wook Chang 2010World Journal of Stem Cells2010,2,2:14
5Specific CD8^+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis显示文摘Hepatocellular carcinoma(HCC), chronic hepatitis B(CHB) and chronic hepatitis C(CHC) are characterized by exhaustion of the specific CD8^+ T cell response. This process involves enhancement of negative costimulatory molecules, such as programmed cell death protein-1(PD-1), cytotoxic T-lymphocyte antigen-4(CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8^+ T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4(tremelimumab and ipilimumab) and PD-1(nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.Elia Moreno-Cubero Juan-Ramón Larrubia 2016World Journal of Gastroenterology2016,22,28:13
6The hypothalamic-spinal dopaminergic system:a target for pain modulation显示文摘Nociceptive signals conveyed to the dorsal horn of the spinal cord by primary nociceptors are subject to extensive modulation by local neurons and by supraspinal descending pathways to the spinal cord before being relayed to higher brain centers. Descending modulatory pathways to the spinal cord comprise,among others, noradrenergic, serotonergic, γ-aminobutyric acid(GABA)ergic, and dopaminergic fibers.The contributions of noradrenaline, serotonin, and GABA to pain modulation have been extensively investigated. In contrast, the contributions of dopamine to pain modulation remain poorly understood.The focus of this review is to summarize the current knowledge of the contributions of dopamine to pain modulation. Hypothalamic A11 dopaminergic neurons project to all levels of the spinal cord and provide the main source of spinal dopamine. Dopamine receptors are expressed in primary nociceptors as well as in spinal neurons located in different laminae in the dorsal horn of the spinal cord, suggesting that dopamine can modulate pain signals by acting at both presynaptic and postsynaptic targets. Here, I will review the literature on the effects of dopamine and dopamine receptor agonists/antagonists on the excitability of primary nociceptors, the effects of dopamine on the synaptic transmission between primary nociceptors and dorsal horn neurons, and the effects of dopamine on pain in rodents. Published data support both anti-nociceptive effects of dopamine mediated by D2-like receptors and pro-nociceptive effects mediated by D1-like receptors.Michelino Puopolo 2019Neural Regeneration Research2019,14,6:10
7WJSC 6^(th) Anniversary Special Issues(2):Mesenchymal stem cells Mesenchymal stem cells help pancreatic islet transplantation to control type 1 diabetes显示文摘Islet cell transplantation has therapeutic potential to treat type 1 diabetes,which is characterized by autoimmune destruction of insulin-producing pancreatic isletβcells.It represents a minimal invasive approach forβcell replacement,but long-term blood control is still largely unachievable.This phenomenon can be attributed to the lack of islet vasculature and hypoxic environment in the immediate post-transplantation period that contributes to the acute loss of islets by ischemia.Moreover,graft failures continue to occur because of immunological rejection,despite the use of potent immunosuppressive agents.Mesenchymal stem cells(MSCs)have the potential to enhance islet transplantation by suppressing inflammatory damage and immune mediated rejection.In this review we discuss the impact of MSCs on islet transplantation and focus on the potential role of MSCs in protecting islet grafts from early graft failure and from autoimmune attack.Marina Figliuzzi Barbara Bonandrini Sara Silvani Andrea Remuzzi 2014World Journal of Stem Cells2014,6,2:10
8Signal structure of the Chinese Area Positioning System显示文摘Proper signal structure is very important in the navigation, positioning, and time services of a satellite navigation system. In this paper, the carrier wave characteristics, ranging code functions, BOC modulation, navigation data rate, the error-correcting methods, and signal channel resource allocation are discussed in terms of the technical characteristics of the transforming satellite navigation system and the resources of communication satellites. The results show that dual-frequency of C band in the Chinese Area Positioning System (CAPS), compound ranging code, a combination of the coarse code and precise code, BOC modulation, separate-channel transmission of different users are compatible with the satellite navigation system at present. The experiments show that the current signal structure can meet the demand of CAPS.LU XiaoChun WU HaiTao BIAN YuJing HUA Yu 2009Science China(Physics,Mechanics & Astronomy)2009,52,3:9
9Clinical development of reovirus for cancer therapy:An oncolytic virus with immune-mediated antitumor activity显示文摘Jun Gong Esha Sachdev Alain C Mita Monica M Mita 2016World Journal of Methodology2016,6,1:8
10基于电流环复合控制的有源电力滤波器研究显示文摘为了有效降低非周期信号对三相三线APF控制性能的影响,提出了一种改进重复控制与传统PI控制相串联的双环控制方法。该方法加入了控制前馈和误差比例系数以提高系统对非周期信号的抗扰性能。结合APF在旋转d,q坐标系中的简化数学模型,建立了电压、电流解耦环节,对解耦后的d,q轴电流i d,i q分别进行控制,并采用SVPWM控制策略,以TM320F28335型DSP为处理器,在APF50A样机上进行了实验,实验结果表明了改进的控制算法具有很好的鲁棒性。杨新华 谢斌 2014电气传动2014,44,2:8
11Collinear holographic data storage technologies显示文摘In the era of information explosion,the demand of data storage is increased dramatically.Holographic data storage technology is one of the most promising next-generation data storage technologies due to its high storage density,fast data transfer rate,long data life time and less energy consumption.Collinear holographic data storage technology is the typical solution of the holographic data storage technology which owns a more compact,compatible and practical system.This paper gives a brief review of holographic data storage,introduces collinear holographic data storage technology and discusses phase modulation technology being used in the holographic data storage system to achieve higher storage density and higher data transfer rate.Xiao Lin Jinpeng Liu Jianying Hao Kun Wang Yuanying Zhang Hui Li Hideyoshi Horimai Xiaodi Tan 2020Opto-Electronic Advances2020,3,3:8
12Advanced modulation formats for underwater visible light communications [Invited]显示文摘In this paper, we present a detailed comparison of applying three advanced modulation formats including carrierless amplitude and phase modulation(CAP), orthogonal frequency division multiplexing(OFDM), and discrete Fourier transform spread orthogonal frequency division multiplexing(DFT-S OFDM) in underwater visible light communication(UVLC) systems. Cascaded post-equalization schemes are suggested to compensate the system impairments. For the first time, a two-level post-equalizer is presented to mitigate the nonlinear effect and improve the system performance of UVLC. The first post-equalization is based on a novel recursive least square Volterra. These modulation formats are all experimentally demonstrated with corresponding digital signal processing(DSP) algorithms. The experimental results show that single carrier modulations including CAP and DFT-S OFDM can outperform OFDM. Our experiment results show that up to 3 Gb/s over a 1.2 m underwater visible light transmission can be achieved by using DFT-S OFDM 64 QAM and CAP-64. The measured bit error rate is well under the hard decision-forward error correction(HD-FEC) threshold of 3.8 × 10^(-3).迟楠 石蒙 2018Chinese Optics Letters2018,16,12:7
13Method of Modulation Recognition Based on Combination Algorithm of K-Means Clustering and Grading Training SVM显示文摘For the existing support vector machine, when recognizing more questions, the shortcomings of high computational complexity and low recognition rate under the low SNR are emerged. The characteristic parameter of the signal is extracted and optimized by using a clustering algorithm, support vector machine is trained by grading algorithm so as to enhance the rate of convergence, improve the performance of recognition under the low SNR and realize modulation recognition of the signal based on the modulation system of the constellation diagram in this paper. Simulation results show that the average recognition rate based on this algorithm is enhanced over 30% compared with methods that adopting clustering algorithm or support vector machine respectively under the low SNR. The average recognition rate can reach 90% when the SNR is 5 dB, and the method is easy to be achieved so that it has broad application prospect in the modulating recognition.Faquan Yang Ling Yang Dong Wang Peihan Qi Haiyan Wang 2018China Communications2018,15,12:7
14Probiotics for the treatment of Clostridium difficile associated disease显示文摘The purpose of this review paper is to update the current and potential future role of probiotics for Clostridium difficile-associated disease (CDAD). Included in this review, is an update on the testing of newer probiotics (e.g. , Bacillus coagulans GBI-30, 6086) in animal models of CDAD. There is a focus on the modulation of signal transduction pathways (i.e. , transcription factors like cAMP response element-binding, activator protein 1, and nuclear factor kappa B), as well as the inhibition of certain kinases (e.g. , p38 mitogen activated protein kinases) by probiotics. Inhibition of signal transduction by probiotics, such as Saccharomyces boulardii , result in multiple effects on intestinal fluid secretion, neutrophil influx into the colon, inflammation, and colonocyte apoptosis that may positively impact CDAD. Recent clinical approaches with probiotics, for the prevention of primary and recurrent CDAD, are also summarized in this review paper. Future directions for the treatment of CDAD by probiotics are also mentioned in this review. In particular, the use of multi-strain probiotic formulations such as Ecologic AAD and VSL #3 may represent a rationale pharmacological approach, particularly as adjunctive therapies for CDAD. Understanding the mechanistic basis of CDAD, and how probiotics interfere at ceratin steps in the pathogenic process, may also present the opportunity to design other multi-strain probiotics that could have a future impact on CDAD.Leo R Fitzpatrick 2013World Journal of Gastrointestinal Pathophysiology2013,4,3:7
15Mesenchymal stem cells: Potential role in corneal wound repair and transplantation显示文摘Corneal diseases are a major cause of blindness in the world. Although great progress has been achieved in the treatment of corneal diseases, wound healing after severe corneal damage and immunosuppressive therapy after corneal transplantation remain prob-lematic. Mesenchymal stem cells(MSCs) derived from bone marrow or other adult tissues can differentiate into various types of mesenchymal lineages, such as osteocytes, adipocytes, and chondrocytes, both in vivo and in vitro. These cells can further differentiate into specific cell types under specific conditions. MSCs migrate to injury sites and promote wound healing by secreting anti-inflammatory and growth factors. In ad-dition, MSCs interact with innate and acquired immune cells and modulate the immune response through their powerful paracrine function. Over the last decade, MSCs have drawn considerable attention because of their beneficial properties and promising therapeutic prospective. Furthermore, MSCs have been applied to various studies related to wound healing, autoim-mune diseases, and organ transplantation. This review discusses the potential functions of MSCs in protecting corneal tissue and their possible mechanisms in corneal wound healing and corneal transplantation.Fei Li Shao-Zhen Zhao 2014World Journal of Stem Cells2014,6,3:7
16A jamming method against bistatic SAR based on modulation theory显示文摘This paper focuses on the jamming problem of bistatic synthetic aperture radar (BiSAR), and a jamming method against BiSAR based on modulation theory is proposed. The proposed jamming method modulates the BiSAR signal with the cosinusoidal phase to generate multi-false targets in range, and further rotates the jammer to generate multi-false targets in azimuth. The range multi-false targets and azimuth multi-false targets form the two-dimensional cover jamming or deception jamming, which can protect the important targets efficiently. The number of false targets, the interval of false targets, and the jamming square can be adjusted flexibly by setting different range jamming parameters and azimuth jamming parameters. The jamming performance and the choosing criteria of jamming parameters are also discussed. Finally, the simulated data verify the effectiveness of the jamming method.RAN Jinhe LI Xiuhe SHEN Yang 2019Journal of Systems Engineering and Electronics2019,30,3:7
17单片机控制太阳能充电控制器显示文摘针对目前太阳能充电控制器对蓄电池的保护不够充分,蓄电池的寿命缩短这种情况,研究确定了一种基于单片机Atmega16的太阳能充电控制器的方案。本设计使用低功耗、高性能的Atmega16单片机作为核心器件对整个电路进行控制。系统硬件电路由太阳能电池充电电路、电压采集和显示电路、单片机控制电路和RS-485串口通信电路组成,主要实现对蓄电池电压的采集和显示。软件部分依据PWM(pulse width modulation)脉宽调制控制策略,编制程序使单片机输出PWM控制信号,控制信号将实现对功率开关器件MOS管开通与关断的控制,从而实现太阳能极板对蓄电池的充电控制[1]。根据控制器的要求,编制软件程序,软件实现蓄电池高效率充电,使蓄电池不过充、过放,保护蓄电池,延长蓄电池使用寿命。李作文 于海月 2015光电技术应用2015,30,3:7
18Analysis of the optical quality by determining the modulation transfer function for anterior corneal surface in myopes显示文摘AIM: To describe the characteristics of modulation transfer function (MTF) of anterior corneal surface, and obtain the the normal reference range of MTF at different spatial frequencies and optical zones of the anterior corneal surface in myopes. · METHODS: Four hundred eyes from 200 patients were examined under SIRIUS corneal topography system. Phoenis analysis software was applied to simulate the MTF curves of anterior corneal surface at vertical and horizontal meridians at the 3, 4, 5 , 6, 7mm optical zones of cornea .The MTF values at spatial frequencies of 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55 and 60 cycles/degree (c/d) were selected. · RESULTS: The MTF curve of anterior corneal surface decreased rapidly from low to intermediate frequency (0-15cpd) at various optical zones of cornea, the value decreased to 0 slowly at higher frequency (>15cpd). With the increase of the optical zones of cornea, MTF curve decreased gradually. 3) In the range of 3 mm- 6 mm optical zones of the cornea, the MTF values measured at horizontal meridian were greater than the corresponding values at horizontal meridian of each spatial frequency, the difference was statistically significant (P <0.05). At 7 mm optical zones of cornea, the MTF values measured at horizontal meridian were less than the corresponding values at vertical meridian at 10-60 spatial frequencies(cpd), and the difference was statistically significant in 25, 30, 35, 40, 45, 50 cpd(P <0.05). · CONCLUSION: MTF can be used to describe the imaging quality of optical systems at anterior corneal surface objectively in detail.Yan-Zhen Zheng, Yao-Yu Li 2012International Journal of Ophthalmology(English edition)2012,5,2:6
19三相电压型PWM整流器直接功率控制策略研究显示文摘针对传统电压定向型直接功率控制(VO-DPC)系统关频率不固定、控制滞后等问题提出了一种基于模型预测的直接功率控制(MP-DPC)策略.这种控制策略使用模型预测控制器来代替滞环比较器,提高了系统响应.这种控制策略还与空间矢量调制技术(Space Vector Pulse Modulation,SVPWM)结合使用,以电源电压的平均电压矢量作为整个控制过程的基矢量,进行电压空间矢量调制控制.同时,这种方法使DPC系统的结构更加简单,降低了设计难度.最后通过仿真实验进行对比分析,验证本文所提方法的可行性和有效性.邱瑞生 2016哈尔滨理工大学学报2016,21,6:6
20Optimal power allocation for secure directional modulation networks with a full-duplex UAV user显示文摘This paper makes an investigation of a secure unmanned aerial vehicle(UAV)-aided communication network based on directional modulation(DM). In this network, ground base station(GBS) acts as a control center to transmit confidential message and artificial noise(AN). The UAV user, moving along a linear flight trajectory, is intended to receive the useful information from GBS. At the same time, it also sends AN signals to further interference eavesdropper’s channel. Aiming at maximizing secrecy rate during the UAV flight process, a joint optimization problem is formulated with respect to power allocation(PA)factors, beamforming vector and AN projection matrices. For simplicity, maximum rate transmission, nullspace projection and the leakage-based method are applied to form the transmit beamforming vector, AN projection matrix at GBS, and AN projection vector at UAV user, respectively. Following this, the optimization problem reduces to a bivariate optimization programme with two PA factors. An alternating iterative algorithm(AIA) is proposed to optimize the two PA factors. Simulation results demonstrate that, compared to the half-duplex(HD) mode, the proposed strategy for full-duplex(FD) mode achieves a higher secrecy rate(SR) and outperforms the FD mode with fixed PA strategy.Zaoyu LU Linlin SUN Shuo ZHANG Xiaobo ZHOU Jinyong LIN Wenlong CAI Jin WANG Jinhui LU Feng SHU 2019Science China(Information Sciences)2019,62,8:6
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