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Contact mode thermal sensors for ultrahigh-temperature region of 2000-3500 K

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Rare Metals 2019年第8期38卷 713-720页

作者： sheng-yong xu Zhen-Hai Wang Li-Jiang Gui Key Laboratory for the Physics and Chemistry of Nanodevices Department of Electronics Peking University Beijing 100871 China Department of Micro-Nano Fabrication Technology Institute of Electrical Engineering Chinese Academy of Sciences Beijing 100190 China

In this article,we reviewed several existing techniques that were capable of detecting local temperatures in the range of 2000-3500 K in a contact *** techniques included several non-standard thermocouples,Seger cones and ultrasonic *** particular,ultrasonic meters made of tungsten(W)wires were proven to be working well in nuclear plant for detecting the central temperature of reaction *** also presented two alternative *** of them was a kind of singlemetal-based thermal sensor made from W,Mo and Ta wires,which utilized the size effect of Seebeck coefficient and theoretically applicable in contact mode measurement up to 3500 *** other was a kind of detectors with micro-/nano-patterns,which utilized the size effect of surface melting point of bulky *** work should shed light on measurement approaches for ultrahigh temperatures in a variety of practical applications.

关键词： Thermocouple Ultrasound Ultrahigh temperature Contact mode Size effect Seebeck effect Surface melting point

Basic and clinical research into chronic obstructive pulmonary disease in China

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Chinese Medical Journal 2010年第4期123卷 491-497页

作者： LI Yuan-yuan LIU Xian-sheng xu yong-jian Department of Respiratory Medicine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Chronic obstructive pulmonary disease （COPD）, one of the most common public health problemsworldwide, is the fourth leading cause of death in the world. In China, respiratory diseases （of which COPD is a major component） are the third leading cause of death in rural areas and the fourth leading cause of death in urban area, accounting for 1 million deaths and over 5 million disabilities each year. COPD ranks first among the burdens in China.1 Hence, medical workers and governments at different levels pay close attention to this disease~ The Respiratory Group under the Chinese Medical Association published the Guidelines for Diagnosis and Management of COPD in 2002^2 and the revised version in 2007^3. This publication serves as a milestone of the development of basic and clinical investigation in China. The guidelines are likely to affect the way for the treatment of COPD in addition to reflect the current knowledge about the underlying causes of COPD and recommend the proper diagnosis and management of COPD.

关键词： pulmonary disease, chronic obstructive prevalence risk factors etiology therapy China

An electromagnetic view of relay time in propagation of neural signals

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Chinese Physics B 2021年第2期30卷 589-594页

作者： Jing-Jing xu San-Jin xu Fan Wang sheng-yong xu School of Microelectronics Shandong UniversityJi'nan 250100China Department of Electronics School of Electronics Engineering and Computer SciencePeking UniversityBeijing 100871China

We review the experimental and computational data about the propagation of neural signals in myelinated axons in mice,cats,rabbits,and frogs published in the past five *** contrast to the natural assumption that neural signals occur one by one in time and in space,we figure out that neural signals are highly overlapped in time between neighboring *** phenomenon was occasionally illustrated in some early reports,but seemed to have been overlooked for some *** shift in time between two successive neural signals from neighboring nodes,defined as relay timeτ,was calculated to be only 16.3μs-87.0μs,i.e.,0.8%-4.4%of the average duration of an action potential peak(roughly 2 ms).We present a clearer picture of the exact physical process about how the information transmits along a myelinated axon,rather than a whole action potential peak,what is transmitted is only a rising electric field caused by transmembrane ion *** in the paper,τrepresents the waiting time until the neighboring node senses an attenuated electric field reaching the threshold to trigger the open *** mechanisms addressed in this work have the potential to be universal,and may hold clues to revealing the exact triggering processes of voltage-gated ion channels and various brain functions.

关键词： neural signal relay propagation velocity electromagnetic field model ion channels

A Woman with Psychogenic Non-epileptic Seizures and Pelvic Mass

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Chinese Medical Sciences Journal 2016年第3期31卷 203-205,206页

作者： Teng-da xu sheng-yong xu Jia-yuan Dai Department of Health Management & Emergency Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences & Peking Union Medical College Department of Emergency Medicine Peking Union Medical College HospitalChinese Academy of Medical Sciences & Peking Union Medical College

MOST cases of encephalitis are caused by viruses but a few have an immunological basis, such as paraneoplastic encephalitis, with specific antibodies identified. One recently characterized encephalitis caused by antibodies is anti-N- methyl-D-aspartate （NMDA） receptor encephalitis. It is a form of paraneoplastic limbic encephalitis associated with ovarian teratoma and has recently been *** NMDA receptor mediates excitatory neurotransmission. It is important for synaptic plasticity, and thus for higher function such as learning and memory. This disorder results in prominent psychiatric symptoms followed by a rapid decline of the level of consciousness, central hypoventilation, seizures, involuntary movements and dysautonomia.

关键词： psychogenic seizure limbic encephalitis ovarian teratoma anti-N-methyl-D-aspartate receptor encephalitis emergency treatment

Expression of Nitric Oxide Synthase Isoenzyme in Lung Tissue of Smokers with and without Chronic Obstructive Pulmonary Disease

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Chinese Medical Journal 2015年第12期128卷 1584-1589页

作者： Wen-Ting Jiang Xian-sheng Liu yong-Jian xu Wang Ni Shi-Xin Chen Department of Respiratory Medicine Tongji Hospital Affiliated to Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China

Background：It has been demonstrated that only 10%-20% cigarette smokers finally suffer chronic obstructive pulmonary disease （COPD）.The underlying mechanism of development remains uncertain so *** oxide （NO） has been found to be closely associated with the pathogenesis of COPD,the alteration of NO synthase （NOS） expression need to be *** study aimed to investigate the alterations of NOS isoforms expressions between smokers with and without COPD,which might be helpful for identifying the susceptibility of smokers developing into ***：Peripheral lung tissues were obtained from 10 nonsmoker control subjects,15 non-COPD smokers,and 15 smokers with *** NOS （nNOS）,inducible NOS （iNOS）,and endothelial NOS （eNOS） mRNA and protein levels were measured in each sample by using real-time polymerase chain reaction and Westem ***：INOS mRNA was significantly increased in patients with COPD compared with nonsmokers and smokers with normal lung function （P 〈 0.001,P =0.001,respectively）.iNOS protein was also higher in COPD patients than nonsmokers and smokers with normal lung function （P 〈 0.01 and P =0.01,respectively）.However,expressions ofnNOS and eNOS did not differ among nonsmokers,smokers with and without ***,there was a negative correlation between iNOS protein level and lung function parameters forced expiratory volume in 1 s （FEV1）（% predicted）（r =-0.549,P =0.001） and FEV1/forced vital capacity （%,r =-0.535,P =0.001）.Conclusions：The expression of iNOS significantly increased in smokers with COPD compared with that in nonsmokers or smokers without *** results suggest that iNOS might be involved in the pathogenesis of COPD,and may be a potential marker to identify the smokers who have more liability to suffer COPD.

关键词： Chronic Obstructive Pulmonary Disease Nitric Oxide Synthase Smoking

Long range electromagnetic field nature of nerve signal propagation in myelinated axons

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Chinese Physics B 2022年第3期31卷 619-623页

作者： Qing-Wei Zhai Kelvin J A Ooi sheng-yong xu C K Ong School of Electrical and Computer Engineering Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Physics Xiamen University MalaysiaSelangor Darul Ehsan 43900Malaysia Department of Electronics School of Electronics Engineering and Computer SciencePeking UniversiyBeijing 100871China Department of Physics National University of Singapore2 Science Drive 3117551 Singapore

The nature of saltatory conduction in myelinated axon described by equivalent circuit and circuit theory is still contentious. Recent experimental observations of action potentials transmitting through disjointed nerve fibers strongly suggest an electromagnetic wave propagation mechanism of the nerve signals. In this paper, we employ the electromagnetic wave model of the myelinated axon to describe action potential signal propagation. We use the experimental frequency-dependent conductivity and permittivity values of the nerve tissues in order to reliably calculate the electromagnetic modes by using electromagnetic mode solvers. We find that the electromagnetic waves above 10 kHz can be well confined in extracellular fluid–myelin sheath–intracellular fluid waveguide and propagate a distance of 7 mm without much attenuation. Our study may serve as one of the fundamental researches for the better understanding of the nervous system.

关键词： action potential propagation and axons neuronal wave propagation neuroscience electrodynamics in the nervous system

Left Circumflex Pseudoaneurysm and Left Anterior Descending Aneurysm in Coronary Artery Due to Behcet＇s Disease

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Chinese Medical Journal 2018年第21期131卷 2626-2627页

作者： Itai-Feng Liu Min Wang yong-sheng xu Xing-Ru Lu Jun-Qiang Lei Department of Radiology First Hospital of Lanzhou University Lanzhou Gansu 730000 China Department of Anesthesiology First Hospital of Lanzhou University Lanzhou Gansu 730000 China

To the Editor： A 33-year-old Chinese male, with a 5-year history of recurrent oral and genital ulcers, was admitted to our hospital for chest tightness, fever, and tiredness from 2 weeks. The patient had been diagnosed with Behcet＇s disease （BD） 3 years before admission to our hospital, suffered from deep venous thrombosis related to BD, and was being treated with prednisolone. Physical examination revealed multiple varisized lesions occurred in the skin of periorbital and lower extremities.

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Role of the extracellular signal-regulated kinase 1/2 signaling pathway in regulating the secretion of bronchial smooth muscle cells in a rat model of chronic asthma

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Chinese Medical Journal 2008年第1期121卷 73-77页

作者： XIE Min LIU Xian-sheng xu yong-jian ZHANG Zhen-xiang BAI Jing NI Wang CHEN Shi-xin Department of Respiratory Medicine Tongji Hospital Affiliated toTongji Medical College Huazhong University of Science andTechnology Wuhan Hubei 430030 China

Background Although it is recognized that bronchial smooth muscle cells （BSMCs） play a key role. in airway remodeling during chronic asthma, it is not well understood how BSMCs exert their inflammatory functions. The extracellular signal-regulated kinase 1/2 （ERK1/2） signaling pathway is an important signaling pathway in chronic asthma but its influence on secretion by BSMCs has not been well-studied. We investigated the impact of ERK1/2 signaling pathway on secretion by BSMCs in a rat model of chronic asthma in this study. Methods To create a rat model of chronic asthma, Wistar rats underwent ovalbumim （OVA） injection and eight weeks of inhalation. BSMCs were isolated and cultured in vitro. Epidermal growth factor, PD98059 and ERK1/2 antisense oligonucleotide were used to explore the role of ERK1/2 signaling pathway. The expression of P-ERK1/2 （phospho-ERK1/2） in BSMCs was analyzed by Western blot and reverse transcriptase-polymerase chain reaction （RT-PCR）. Secretion of BSMCs was detected by enzyme-linked immunosorbent assay （ELISA）. Results Phospho-ERK1/2 expression was increased in BSMCs of chronic asthmatic rats compared with the controls. PD98059 inhibited expression of phospho-ERK1/2 protein, while treatment with an antisense oligonucleotide inhibited the expression of P-ERK1/2 mRNA and protein. BSMCs obtained from the chronic asthma group secreted significantly greater quantities of growth factors （transforming growth factor （TGF）-β1, vascular endothelial growth factor （VEGF） and connective tissue growth factor （CTGF））, cytokines （regulated upon activation, normal T cell-expressed and secreted （RANTES） and eotaxin）, and extracellular matrix （fibronectin and collagen I） compared with normal controls. Epidermal growth factor stimulated secretion in both groups, but the response of the chronic asthma group was more intense. Both PD98059 and antisense oligonucleotide suppressed secretion by BSMCs in chronic ashmatic rats. Antisense oligonucleotide reduced the le

关键词： extracellular signal-regulated kinase asthma bronchial smooth muscle cell secretion

Gastric foreign body granuloma caused by an embedded fishbone:A case report

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World Journal of Gastroenterology 2014年第12期20卷 3388-3390页

作者： Guo-Dong Shan Zong-Pin Chen yong-sheng xu Xiao-Qin Liu Yuan Gao Feng-Ling Hu Ying Fang Cheng-Fu xu Guo-Qiang xu Department of Gastroenterology the First Affiliated HospitalCollege of MedicineZhejiang University Department of Gastroenterology the People’s Hospital of Jingning Department of General Surgery the First Affiliated HospitalCollege of MedicineZhejiang University Digestive Endoscopy Center the First Affiliated HospitalCollege of MedicineZhejiang University

Fishbones are the most commonly ingested foreign bodies that cause gastrointestinal tract penetration. However, fishbones embedded in the gastrointestinal tract that lead to foreign body granulomas that mimic submucosal tumors are rare. Herein, we describe a 56-year-old woman who presented with a 20-day-history of upper abdominal pain. Endoscopy revealed an elevated lesion in the gastric antrum. An abdominal computed tomography scan showed a mass in the gastric antrum and a linear calcified lesion in the mass. An endoscopic ultrasonography examination revealed a 3.9 cm × 2.2 cm, irregular, hypoechoic mass with indistinct margins in the muscularis propria layer. The patient was initially diagnosed as having a submucosal tumor, and subsequent surgical resection showed that the lesion was a foreign body granuloma caused by an embedded fishbone. Our case indicated that the differential diagnosis of a foreign body granuloma should be considered in cases of elevated lesions in the gastrointestinal tract.

关键词： Gastric Foreign body granuloma Fishbone Endoscopic ultrasonography Computed tomography