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Progress in Natural science:Materials International 2007年第8期17卷 913-918页

作者： Xu Jin~1 Hu Guangshu~(1**) Huang Houbin~2 (1.department of Biomedical Engineering,Tsinghua university,beijing 100084,china 2.department of Ophthalmology,General hospital of Chinese PLA,beijing 100853,china) [a]department of Biomedical Engineering Tsinghua University Beijing China [b]department of Ophthalmology General Hospital of Chinese PLA Beijing China

The multifocal electroretinogram (mfERG) is a newly developed electrophysiological *** this paper,a classifi- cation method is proposed for early diagnosis of the diabetic retinopathy using mfERG *** records were obtained from eyes of healthy individuals and patients with diabetes at different *** each mfERG record,103 local responses were *** value of each point on all the mfERG local responses was looked as one potential feature to classify the experimental *** sub- sets were selected from the feature space by comparing the inter-intra *** on the selected feature subset,Fisher's linear classi- fiers were *** the final classification decision of the record was made by voting all the classifiers' *** the method to classify all experimental subjects,very low error rates were *** crucial properties of the diabetic retinopathy classification method are also discussed.

关键词： diabetic retinopathy multifocal electroretinogram feature selection linear classifier

Right prefrontal laterality of Chinese boys during a Chinese high conflict stroop task measured by multi-channel near-infrared spectroscopy imaging

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Progress in Natural science:Materials International 2007年第9期17卷 1023-1028页

作者： Liu Jiacheng1,Bai Jing1,Peng Miao2,Fan Xiaofei1 and Guo Qiyong3(1.department of Biomedical Engineering,Tsinghua university,beijing 100084,china 2.department of Electroneurophysiology,the sixth hospital of Peking university,beijing 100085,china 3.department of Radiology,The second hospital of china medical university,shenyang 110003,china) department of Biomedical Engineering Tsinghua University Beijing 100084 China 2. department of Electroneurophysiology the Sixth Hospital of Peking University Beijing 100085 China 3． department of Radiology The Second Hospital of China Medical University Shenyang 110003 China

some studies have shown that native Chinese speakers have different laterality in matched stroop tasks from native English ***,many imaging data,which show left laterality of English-matched stroop interference,have been *** a few functional imaging studies have been conducted to investigate the phenomenon of the Chinese version of stroop *** this study,functional activity in the lateral prefrontal cortex of a group of normal Chinese boys with functional near-infrared imaging during a stroop color-word task was measured to show different stroop interferences in the prefrontal *** results show obvious fluctuation of the cerebral blood volume in the right prefrontal cortex in all boys,which agrees with the finding of previous studies,that is,Chinese native boys have right laterality in their brain when the Chinese version of stroop color-word task is applied.

关键词： laterality stroop effect prefrontal cortex near-infrared

Generalized gradient projection neural networks for nonsmooth optimization problems

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science china(Information sciences) 2010年第5期53卷 990-1005页

作者： LI GuoCheng 1 , sONG shiJi 2 ? & WU Cheng 2 1 department of Mathematics, beijing Information science and Technology university, beijing 100192, china 2 department of Automation, Tsinghua university, beijing 100084, china 1. department of Mathematics Beijing Information Science and Technology University Beijing 100192 China2. Department of Automation Tsinghua University Beijing 100084 China

Generalized gradient projection neural network models are proposed to solve nonsmooth convex and nonconvex nonlinear programming problems over a closed convex subset of R n . By using Clarke’s generalized gradient, the neural network modeled by a differential inclusion is developed, and its dynamical behavior and optimization capabilities both for convex and nonconvex problems are rigorously analyzed in the framework of nonsmooth analysis and the differential inclusion theory. First for nonconvex optimization problems, the quasi convergence results similar to those achieved by previous work are proved. For convex optimization problems, the global convergence results are proved, i.e. any trajectory of the neural network converges to an asymptotically stable equilibrium point, which is an optimal solution of the primal problem whenever it exists. This result remains valid even if the initial condition is chosen outside the feasible set. In addition, an asymptotic control result involving a Tykhonov like regularization shows that any trajectory of the revised neural network can be forced to converge toward a particular optimal solution of the primal problem. Finally, two simulation optimization algorithms for solving the optimization and control problems are designed respectively, and three typical simulation experiments are illustrated to present the accuracy and efficiency of theoretical convergence results of this paper.

关键词： nonsmooth optimization problem generalized gradient projection networks differential inclu sions convergence

Mutagenicity and Induction of Drug-metabolizing Enzyme Activity by LPG Combustion Particulates in Rats

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Biomedical and Environmental sciences 1994年第4期7卷 346-356页

作者： YIN XUE-JUN LIU JUN-ZHUO LI YONG-sHUN KONG XIANG-HUAN AND LIU HONG(department of Environmental Health, capital university of medical sciences, beijing 100054, china department of Environmental Health, beijing medical university, beijing, china) department of Environmental Health Capital University of Medical Sciences Beijing China.

Methylene chloride extracts of particulates from liquefied petroleum gas (LPG) combustion appliance were studied by using Ames test, micronucleus test and inducibility of pulmonary and hepatic aryl hydrocarbon hydroxylase (AHH) and glutathione s-transferase (GsT) in rats. The extracts showed mutagenicity for salmonella typhimurium strain TA98 and its derivatives TA98NR and TA98/1,8-DNP6 with or without s9 mix. The revertants in strains TA98NR and TA98/1,8-DNP6 were less than 40% and 50% of that in strain TA98 without s9 mix, respectively. Positive results were obtained in mouse bone marrow micronucleus assay. Intratracheal instillation of the extracts led to increase in pulmonary (but not hepatic) AHH and GsT activities in rats. It was seen that AHH was more sensitive than GsT to induction by the extracts

关键词： Activity Mutagenicity and Induction of Drug-metabolizing Enzyme Activity by LPG Combustion Particulates in Rats DNP LPG

Increase of peripheral Th17 lymphocytes during acute cellular rejection in liver transplant recipients

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Hepatobiliary & Pancreatic Diseases International 2012年第6期11卷 606-611页

作者： Hua Fan, Li-Xin Li, Dong-Dong Han, Jian-Tao Kou, Ping Li, Qiang He department of Hepatobiliary surgery, beijing Chaoyang hospital, capital medical university, beijing 100020, china department of Hepatobiliary surgery Beijing Chaoyang Hospital Capital Medical University Beijing 100020 China

BACKGROUND: Although many human inflammatory and autoimmune diseases were previously considered to be mediated by T helper type 1 (Th1) cells, the recently described Th17 cells play dominant roles in several of these diseases. We and others speculated that allograft rejection after organ transplantation may also involve Th17 cells. Episodes of acute rejection occur in 30% of liver transplants. This study aimed to determine the frequency of circulating Th17 cells in patients who had received liver transplants for benign end-stage liver disease and to identify any association between acute rejection episodes and levels of Th17 cells in the peripheral blood. METHODs: A prospective study compared Th17 cells from 76 consecutive benign end-stage liver disease patients who had undergone orthotopic liver transplantation from 2007 to 2011 with those from 20 age-matched healthy individuals. Peripheral blood samples were collected at different time points within one year after transplant. Blood samples and liver biopsies were also collected at the diagnosis of acute rejection. Percentages of circulating CD4+ IL-17+ cells were measured by flow cytometry The transplant patients were classified into two groups: a rejection group consisting of 17 patients who had an episode of acute rejection, and a non-rejection group comprising the remaining 59 patients with no acute rejection episodes Percentages of circulating Th17 cells were compared between the two groups and controls. REsULTs: The levels of circulating CD4+ IL-17+ T cells in the rejection group were higher during acute rejection than those in the non-rejection group (2.56±0.43% versus 1.79±0.44% Ps in peripheral blood was positively correlated with the rejection activity index (r=0.79, P=0.0002).CONCLUsION: Circulating Th17 cells may be useful as a surrogate marker for predicting acute rejection in liver transplant recipients.

关键词： liver transplantation Th17 cells acute cellular rejection transplant immunology

Effects of the CNTF-collagen gel-controlled delivery system on rat neural stem/progenitor cells behavior

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science china(Life sciences) 2010年第4期53卷 504-510页

作者： YANG ZhaoYang1, QIAO Hui2 & LI XiaoGuang1,3 1school of Biological science and medical Engineering, Beihang university, beijing 100191, china 2Public Heath school, Ningxia medical university, Yinchuan 750004, china 3beijing Institute for Neuroscience, capital medical university, beijing 100069, china 1. school of Biological science and medical Engineering Beihang University Beijing 100191 China2. Public Heath School Ningxia Medical University Yinchuan 750004 China3. Beijing Institute for Neuroscience Capital Medical University Beijing 100069 China

The injury of central nervous system (CNs) usually causes the cavity formation. Although transplantation of neural stem/precursor cells (NsPCs) into the lesioned area of CNs has been shown to be implicated in the functional restoration, the therapeutic result is limited by the poor survival of NsPCs as well as their insufficient proliferation and differentiation abilities. Type-1 collagen is considered as a candidate scaffold or drug delivery system to overcome the aforementioned obstacle. This study observed the effects of the CNTF (ciliary neurotrophic factor)-collagen gel-controlled delivery system and daily addition of soluble-form CNTF on the NsPC survival, migration, proliferation and differentiation. The results showed that, within 12 h of the initial co-culture, CNTF was released in a burst pattern, then the CNTF-collagen gel-controlled delivery system stably released CNTF for up to 12 d. The cell viability test, together with immunohistochemistry, RT-PCR and Western blotting, showed that the CNTF-collagen gel-controlled delivery system supported the NsPCs seeded on the surface of collagen gel survival and facilitated their migration and proliferation. The daily addition of soluble-form CNTF to the medium had similar effects to the CNTF-collagen gel-controlled delivery system, but large quantities of soluble-form CNTF were consumed during the entire process. Taken together, the CNTF-collagen gel-controlled delivery system not only provides a physical scaffold for the transplanted NsPCs to adhere and migrate, but also facilitates the NsPC survival, growth and proliferation, simultaneously reducing the consumption of the expensive growth factors. This system may be used to enhance the microenvironment in the lesioned area of CNs.

关键词： spinal cord neural stem/progenitor cells control release type-1 collagen CNTF

Dense coding scheme using superpositions of Bell-states and its NMR implementation

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science china(Physics,Mechanics & Astronomy) 2005年第1期48卷 57-67页

作者： ZHANG Jingfu, XIE Jingyi, DENG Zhiwei & LU Zhiheng Key Laboratory for Quantum Information and Measurements, department of Physics, Tsinghua university, beijing 100084, china Center for Quantum Information, Tsinghua university, beijing 100084, china department of Materials science and Engineering, beijing Normal university, beijing 100875, china Testing and Analytical Center, beijing Normal university, beijing 100875, china department of Physics, beijing Normal university, beijing 100875, china 1. Key Laboratory for Quantum Information and Measurements Department of Physics Tsinghua University 100084 Beijing China 2. Center for Quantum Information Tsinghua University 100084 Beijing China 3. department of Materials science and Engineering Beijing Normal University 100875 Beijing China 4. Testing and Analytical Center Beijing Normal University 100875 Beijing China 5. department of Physics Beijing Normal University 100875 Beijing China

Dense coding using superpositions of Bell-states is proposed. The generalized Grover's algorithm is used to prepare the initial entangled states, and the reverse process of the quantum algorithm is used to determine the entangled state in the decoding measurement. Compared with the previous schemes, the superpositions of two Bell-states are exploited. Our scheme is demonstrated using a nuclear magnetic resonance (NMR)quantum computer. The corresponding manipulations are obtained. Experimental results show a good agreement between theory and experiment. We also generalize the scheme to transmit eight messages by introducing an additional two-state system.

关键词： dense coding, superpositions of Bell-states, generalized Grover's algorithm, nuclear magnetic res-onance, quantum computer.

A novel arterial pouch model of saccular aneurysm by concomitant elastase and collagenase digestion

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Journal of Zhejiang university-science B(Biomedicine & Biotechnology) 2007年第10期8卷 697-703页

作者： YANG Xin-jian, LI Li, WU Zhong-xue (department of Interventional Neuroradiology, beijing Neurosurgical Institute, capital medical university, beijing 100050, china) department of Interventional Neuroradiology Beijing Neurosurgical Institute Capital Medical University Beijing 100050 China

Background: An ideal aneurysm model of cerebral aneurysm is of great importance for studying the pathogenesis of the lesion and testing new techniques for diagnosis and treatment. several models have been created in rabbits and are now widely used in experimental studies; however, every model has certain intrinsic limitations. Here we report the development of a novel saccular aneurysm model in rabbits using an arterial pouch that is subject to in vitro pre-digestion with combined elastase and collagenase. Methods: A segment of right common carotid artery (CCA) was dissected out and treated with elastase (60 U/ml, 20 min) followed by type I collagenase (1 mg/ml, 15 min) in vitro. The graft was anastomosed to an arterial arch built with the left CCA and the remaining right CCA, while the other end of the graft was ligated. The dimension and tissue structure of the pouch were analysed immediately, 2 or 8 weeks after operation. Findings: Ten terminal aneurysms were produced. The gross mor-phology of the aneurysm resembles the human cerebral terminal aneurysms. We have observed the following pathological changes: (1) growth of the aneurysm (mean diameter increased from (2.0±0.1) to (3.2±0.3) mm at 2 weeks, P2) thinning of the aneurysmal wall (the mean wall thickness decreased to 44% at 2 weeks), which was accompanied by significant losses of elastic fibres, collagen and the cellular component; and (3) spontaneous rupture (3 out of 9, one aneurysm ruptured 24 h after operation with the other two at 2 and 4 weeks respectively). Conclusion: This rabbit arterial pouch model mimics human cerebral aneurysms in relation to morphology and histology. In particular, this model exhibited an increased tendency of spontaneous rupture.

关键词： Animal model Collagenase Elastase Intracranial aneurysm

CALCULATING MODELs OF MAss ACTION CONCENTRATIONsFOR MATTEs (Cu_2s-Fes-sns)INVOLVING EUTECTIC

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Acta Metallurgica sinica(English Letters) 1997年第5期10卷 392-397页

作者： J. Zhang (department of Metallurgy, university of science and Technology beijing, beijing 100083, china) Univ of science and Technology Beijing Beijing China

Based on the facts that cations and anions of molten salts and binary basic oxide solid solutions do not separate from each other as well as that the electric conductivities of mattes are greater than that of salts and basic oxide solid solutions, the calculating models of mass action concentrations for binary and ternary mattes involving eutectic have been formulated. The results of calculation agree well with the values measured;this in turn shows that the calculating models can reftect the structural characteristics of the mattes concerned.

关键词： matte activity eutectic mass action concentration

Formation of superoxide Radical and Hydrogen Peroxide Enhanced by Trinitrotoluene in Rat Liver, Brain, Kidney, and Testicle in Vitro and Monkey Liver in Vivo

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Biomedical and Environmental sciences 1989年第1期2卷 72-77页

作者： KONG LINGYUAN, JIANG QUANGUAN,~2 AND QU QINGsHAN department of Occupational Health, school of Public Health, beijing medical university, beijing, china department of Occupational Health School of Public Health Beijing Medical University China.

Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria and microsomes in vivo. The effects were more prominent at higher TNT concentrations. These findings indicate that TNT enhances the production of superoxide radicals (O_2^-) and hydrogen peroxide (H_2O_2). The production of O_2^- was more prominent in systems containing added TNT than in those containing added benzyl viologen. H_2O_2 production by mitochondria was more pronounced in the liver than in other organs, but its production by microsomes was more pronounced in the brain than in other organs. The results suggest that TNT undergoes cycling reduction which produces oxidative stress. 1989 Academic Press, Inc.

关键词： Brain Formation of superoxide Radical and Hydrogen Peroxide Enhanced by Trinitrotoluene in Rat Liver Kidney and Testicle in Vitro and Monkey Liver in Vivo