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science china(Information sciences) 2011年第4期54卷 898-908页

作者： ZHANG Xu 1,PEI WeiHua 1,HUANG BeiJu 1,WANG shuJing 1,GUAN Ning 1,GUO Kai 1,WANG Yu 1,GUI Qiang 1,CHEN Jin 1,WANG Kai 2,WU HuiJuan 2,LI XiaoXin 2,LI Kai 3 & CHEN HongDa 1 1 state Key Laboratory on Integrated Optoelectronics,Institute of semiconductors,Chinese Academy of sciences,beijing 100083,china 2 department of Ophthalmology,people’s hospital of peking university,beijing 100044,china 3 department of Epidemiology and Biostatistics,Health science Center,peking university,beijing 100083,china 1. state Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China2. Department of Ophthalmology People’s Hospital of Peking University Beijing 100044 China3. Department of Epidemiology and Biostatistics Health Science Center Peking University Beijing 100083 China

A prototype chip with 2×2 pixels for implanting in blind patients affected by outer retinal degeneration is presented in this *** visual prosthesis chip imitates the degenerated photoreceptor cells,senses the incident light and stimulates the remaining healthy layers of retina or optic *** pixel integrates photodiode and stimulus pulse generator,converting the illumination on the eyes into 3-bit resolution bi-phasic current ***-chip charge cancellation modules are used to discharge each electrode site for tissue *** prototype chip is designed and fabricated in 0.18-μm N-well CMOs (complementary metal oxide semiconductor) 1P6M Mix-signal process,with a ±2.5 V dual voltage *** functionality of the fabricated chip is demonstrated on anesthetized *** responses in visual cortex are successfully evoked by the neuro-stimulus chip through an on-board trigger interface and flexible electrode.

关键词： biomedical microelectronics visual prosthesis functional electrical stimulation acute animal ex- periment electrical evoked potential (EEP) test

Circadian expression of clock genes and angiotensin Ⅱ type 1 receptors in suprachiasmatic nuclei of sinoaortic-denervated rats

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Acta Pharmacologica sinica 2007年第4期28卷 484-492页

作者： Hui LI~2,Nmg-ling sUN~(2,4),Jin WANG~3,Ai-jun LIU~3,Ding-feng sU~(3,4)~2department of Cardiology,peking university people's hospital,beijing 100044,china ~3department of Pharmacology,second MilitaryMedical university,shanghai 200433,china department of Cardiology Peking University People's Hospital Beijing China department of Pharmacology Second Military Medical University Shanghai China

Aim:To investigate whether the circadian expression of central clock genes andangiotensin Ⅱ type 1 (AT1) receptors was altered in sinoaortic-denervated (sAD)***:Male sprague-Dawley rats underwent sinoaortic denervation or asham operation at the age of 12 *** weeks after the operation,bloodpressure and heart period were measured in the conscious state in a group ofsham-operated (n=10) and sAD rats (n=9).Rest sAD and sham-operated ratswere divided into 6 groups (n=6 in each group).The suprachiasmatic nuclei (sCN)tissues were taken every 4 h throughout the day from each group for the determi-nation of the mRNA expression of clock genes (Per2 and Bmal1) and the AT1receptor by RT-PCR;the protein expression of Per2 and Bmal1 was determined byWestern ***:Blood pressure levels in the sAD rats were similar tothose of the sham-operated ***,blood pressure variabilities signifi-cantly increased in the sAD rats compared with the sham-operated *** variation of clock genes in the sCN of the sham-operated rats was char-acterized by a marked increase in the mRNA and protein expression during ***2 and Bmal1 mRNA levels were significantly lower in the sAD rats,especially during dark *** blot analysis confirmed an attenuation ofthe circadian rhythm of the 2 clock proteins in the sCN of the sAD ***1receptor mRNA expressions in the sCN were abnormally upregulated in the lightphase,changed to a 12-h cycle in the sAD ***:The circadian varia-tion of the 2 central clock genes was attenuated in the sAD *** baroreflexdysfunction also induced a disturbance in the expression of AT1 receptors in thesCN.

关键词： circadian rhythm arterial baroreflex clock genes sinoaortic denervation reninangiotensin system

On　the　Mechanism　of　Coal　Mine　shaft　Damage　Caused　by　subsidence　in　Xuhuai　Area,southeast　china

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Communications in Nonlinear science and Numerical simulation 1997年第2期2卷 19-22+24页

作者： siwen BI, Xiangdong LOU + & Bing XU + (department of Geology, peking university, beijing, of china) +(Institute of Geology Chinese Academy of science, people’s Republic of china) department of Geology Peking University Beijing 100871 China Institute of Geology Chinese Academy of Science Beijing China

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关键词： shaft damage caused subsidence numerical modeling

Morphological and functional changes in the blood-spinal cord barrier of rabbits in an experimental spinal cord presyrinx state

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Neural Regeneration Research 2006年第7期1卷 597-600页

作者： Jianfeng Li1, Haiying Liu1, Qingjun Zhang2 1department of Neurosurgery, Fourth hospital, Hebei Medical university, shijiazhuang 050011, Hebei Province, china 2department of Neurosurgery, people’s hospital, peking university, beijing 100044, china department of Neurosurgery Hebei Medical University Shijiazhuang 050011 Hebei Province China department of Neurosurgery People's Hospital Peking University Beijing 100044 China

BACKGROUND: Presyrinx state of spinal cord can reflect the initial lesion of syringomyelia (sM). The early trials has proved that ischamia and edema are main pathological changes of presyrinx state. OBJECTIVE: To establish sM model of rabbits for investigating the relationship between changes of morphous and function of blood-spinal cord barrier and the edema degree, histological changes in presyrinx state of sM, and to explore the mechanism of the presyrinx state of sM. DEsIGN: Randomized controlled animal experiment. sETTING: department of Neurosurgery, Fourth hospital, Heibei Medical university. MATERIALs: sixty Chinese healthy white rabbits, aged 3.5-4.5 months, weighing 1.5-2.0 kg, were provided by Experimental Animal Center of Hebei Medical university [certification: (sYXK(Ji)2003-0026)]. Evan's blue (EB) and dimethylformamide (DMF) were purchased from Jingmei Biotech Co., Ltd. RM2125 paraffin section cutter (Leica Company, Japan), H-7500 transmission electron microscope (Hitachi Company, Japan), PM-20 light microscope photograph system (Olympus Company, Japan). METHODs: The experiment was carried out in the Laboratory of Neurosurgery department, second hospital of Hebei Medical university from January to June 2006. ① All the rabbits were randomly divided into two groups: model group (n =40), control group (n =20). Rabbits in two groups were divided into five subgroups once again at five time points (1st, 3rd, 7th, 14th, 21st days, n =8 and n =4 at each time point in the model group and control group, respectively). Under ketamine anesthesia, 0.6 mL Kaolin solution (250 g/L, 37 ℃) was injected into the cisterna magna of rabbits in model group, while 0.6 mL physiological saline (37 ℃) was injected into the rabbits of control group. ② On the 1st, 3rd, 7th, 14th, 21st days after kaolin injection, cervical cord samples were harvested after sacrifice of animal. Quantitative analysis on the function of blood-spinal cord barrier was performed by Evan's blue technique

关键词： Morphological and functional changes in the blood-spinal cord barrier of rabbits in an experimental spinal cord presyrinx state

URBAN GROWTH, TRANsPORTATION sYsTEM AND COMMERCIALNETWORK OF beijing

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Journal of Geographical sciences 1995年第3期5卷 15-31页

作者： Yang Wuyang(department of Geography, peking university, beijing 100871)people’s Republic of china

In this afticle, three uopt problems on the developlnent and plabong of beijing metropolis are expounded (1) Having analyzed the process of urbanlzation dunng 45 years, the autihor divides it into three stages :city expansion, qrban sprawl and fonmation of centnpotal urban nngr. Then a rank-number-size law is pLif fotward to predict the development and allocation of satellite towns (2) Having looked back on the change of urban transpoftation nforork, the atlthor points out its merits and *** to the increases of traffic flow, improving measures for the urban road systems are demonstrated. (3) Having reviewed the llistory of commercial distnbution and referred to previous lnodels, the author roprds the spatial structure of business as a combined network from central place and idealized stnucture of lnetropolitan area. The trade and service orgaluzation in n1ain urban area and peripheral zone can be planned with defferent ways. The atlthor predicts a rational network of commerce and service of beijing with a strong BCD Which is accepted by some trade authorities

关键词： urban growth central place theory transportation system,commercial network

NUMERICAL sIMULATION OF HUMAN AIR BREATHING NEAR THE NOsE OUTLET

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Journal of Hydrodynamics 1999年第3期11卷 105-110页

作者： Ma Heng Buji people′s hospital, shengzhen 518112, P.R.china An Yi ran, Zhuang Ning department of Mechanics, peking university, beijing 100871, P.R.china Yan Dong beijing Zhongguancun hospital, beijing 100080, P.R.china (Received Dec. 30, 1998

Numerical method is used to simulate the air breathing near the outlet of human nose. The process of breathing is visualized. The distribution of the exhausted air density may be useful in designing the medical equipm... 详细信息

关键词： human breathing N s equations air refreshing

ECOLOGICAL AND sOCIO-ECONOMIC REHABILITATION IN THE KARsT OF sOUTHWEsT china

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Journal of Geographical sciences 1997年第2期7卷 24-32页

作者： Cai Yunlong department of Geography, peking university, beijing 100871 people’s Republic of china

The Karst of southwest china is a typical representative of poverty stricken region with impoverishment-degradation spiral. To essentially break away from this vicious circle, the local ecology, economy and society should be rehabilitated, and hence to strengthen the self-development capacity building of the localities. Two considerations are stressed in this article: (1) Poverty alleviation is a system project with great complexities. Any single approach is difficult to success and integrated measures should be taken. (2) some typical and feasible areas should be selected to demonstrate the project of poverty alleviation and ecological, socio-economic reconstruction. Then, they can be used as a model to promote the sustainable development of the whole region. Based upon these ideals, a project entitled “Reversal of Impoverishment-Degradation spiral in the Karst of southwest china' was proposed and has been listed in 《Priority Programme for china's Agenda 21》.

关键词： poverty alleviation environmental degradation capacity building ecological and socio-economic rehabilitation karst areas southwest china.

Changes of CD8+CD28-T regulatory cells in rat model of colitis induced by 2,4-dinitrofluorobenzene

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World Journal of Gastroenterology 2003年第11期9卷 2528-2532页

作者： Wen-Bin Xiao, department of Gastroenterology, peking university people’s hospital, beijing 100044, china Yu-Lan Liu, department of Gastroenterology, peking university people’s hospital, beijing 100044, china department of Gastroenterology Peking University People's Hospital Beijing 100044 China.

AIM:To determine the changes of CD8+ T subsets especially CD8+CD28-T regulatory cells in rat model of experimental colitis induced by 2,4-dinitrofluorobenzene (DNFB). METHODs:The rat model of experimental colitis was induced by enema with *** days later,colonic intraepithelial and splenic lymphooltes were isolated from colitis animals (n=16) and controls (n=8).The proportion of CD8+ T cells,CD8+CD28+ T cells and CD8+CD28-T regulatory cells were determined by flow cytometry. REsULTs:The model of experimental colitis was successfully established by DNFB that was demonstrated by bloody diarrhea,weight loss and colonic *** proportion of CD8+ T cells in either splenic or colonic intraepithelial lymphocytes was not significantly different between colitis animals and controls (spleen:34.6±7.24 % vs 33.5±9.41%, colon:14.0±8.93 % vs 18.0±4.06 %,P>0.05).But CD8+CD28- T regulatory cells from colitis animals were significantly more than those from controls (spleen:11.3±2.26 % vs 5.64±1.01%, colon:6.50±5.37 % vs 1.07±0.65 %,Pst, CD8+CD28+ T cells from colitis animals were less than those from controls (spleen:23.3±6.14 % vs 27.8±9.70 %,P=0.06; colon:7.52±4.18 % vs 16.9±4.07 %,P28-T regulatory cells in splenic and colon intraepithelial CD8+ T cells from colitis animals was higher than that from controls (spleen:33.3±5.49 % vs 18.4±7.26 %, colon:46.0±14.3 % vs6.10±3.72 %,PsION:Experimental colitis of rats can be induced by DNFB with simplicity and good *** proportion of CD8+CD28-T regulatory cells in rats with experimental colitis is increased,which may be associated with the pathogenesis of colitis.

关键词： Animals Antigens, CD28 CD8-Positive T-Lymphocytes Colitis Colon Dinitrofluorobenzene Disease Models, Animal Flow Cytometry Male Rats Rats, sprague-Dawley Research support, Non-U.s. Gov't specific Pathogen-Free Organisms spleen

LAND UsE sTRATEGIEs IN sPECIAL ECONOMIC ZONEs OF china:THE CAsE sTUDY OF HAINAN PROVINCE

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Journal of Geographical sciences 1995年第2期5卷 13-20页

作者： Cai Yunlong(department of Geography, peking university, beijing 100871people’s Republic of china)

special economic zones are important bridges between chinaand intemational market. Their economic structure is being transformed andnew land use strategies should be taken correspondingly. HainanProvince, as the biggest special economic zone, has great superiorities andpotentialities for the development of land use. In order to realize the goal,the present land use decision should be mainly guided by market, moreattention should be paid to tropical agriculture and aquatic productindustry, the principle of sustainable development should be strengthened,and the area of farmland for grain production should be stabilized.

关键词： land use situation and strategy special economic zone china,Hainan Province