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Non-invasive in Situ Simultaneous Measurement of Multi-parameter Mechanical Properties of Red Blood Cell Membrane

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Acta Biochimica et Biophysica Sinica 2005年第6期37卷 391-395页

作者： Jing LI~(1.2) Yao-Xiong HUANG~1 Tao JI~1 Mei TU~1 Xuan MAO~1 Wen-Xin CHEN~1 Guang-Wei CHEN 1 Institute of Biomedical Engineering, Jinan university, guangzhou 510632, china 2 State Key Laboratory for Biocontrol, school of Life Science, sun yat-sen university, guangzhou 510275, china Institute of Biomedical Engineering Jinan University Guangzhou 510632 China State Key Laboratory for Biocontrol School of Life Science Sun Yat-Sen University Guangzhou 510275 China

The purpose of this study was to develop a new dynamic image analyzing technique that willgive us the ability to measure the viscoelastic parameters of individual living red blood cells non-invasively,insitu and in real *** this technique,the bending modulus Kc,the shear elasticity μ and their ratio ε weremeasured under different temperatures,oxygen partial pressures and osmotic *** results not onlyshow the effects of external conditions on mechanical properties of cell membranes including deformability,flexibility,adhesive ability and plasticity,but also demonstrate that the technique can be used to measure cellmembrane parameters continuously under several physiological and pathological conditions.

关键词： fast image analyzing red blood cell(RBC) cell membrane elastic property

Steganalysis of stochastic modulation steganography

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Science in china(Series F) 2006年第3期49卷 273-285页

作者： HE Junhui1,2 & HUANG Jiwu1,2 1. school of Information Science and Technology, sun yat-sen university, guangzhou 510275, china 2. Guangdong Province Key Laboratory of Information Security, guangzhou 510275, china school of Information Science and Technology Sun Yat-sen University Guangzhou China Guangdong Province Key Laboratory of Information Security Guangzhou China

Stochastic modulation steganography embeds secret message within the cover image by adding stego-noise with a specific probabilistic distribution. No method is known to be applicable to the estimation of stochastic modulation steganography. By analyzing the distributions of the horizontal pixel difference of images before and after stochastic modulation embedding, we present a new steganalytic approach to accurately estimate the length of secret message in stochastic modulation steganography. The pro- posed method first establishes a model describing the statistical relationship among the differences of the cover image, stego-image and stego-noise. In the case of stegoimage-only steganalysis, rough estimate of the distributional parameters of the cover image＇s pixel difference is obtained with the use of the provided stego-image. And grid search and Chi-square goodness of fit test are exploited to estimate the length of the secret message embedded with stochastic modulation steganography. The experimental results demonstrate that our new approach is effective for steganalyzing stochastic modulation steganography and accurately estimating the length of the secret message.

关键词： information hiding steganography steganalysis stochastic modulation statistical distribution models of difference.

PET Imaging of brain tumor with 13N-NH3

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PET Imaging of brain tumor with 13N-NH3

Detection of Gene Alteration for Color Vision Defects by Polymerase Chain Reaction

首届全国分子核医学暨分子影像学学术交流会

作者： Zhang Xiansong department of Nuclear medicine, The First Affiliated Hospital, sun yat-sen university, guangzhou, china, 510080

Background Hoop et al. (J Nucl Med. 1976;17:473-479) observed 1 recurrent astrocytoma and 1 glioma showed reduced uptake of 13N-NH3 at the lesions. Schelstraete et al. (Br J Radiol. 1982;55:797-804) observed litter or no extra uptake of 13N-NH3 in 4 primary brain tumors. Benard et al. (Semi Nucl Med. 2003;33:148-162) thought 13N-13N-NH3 was unsuccessful in visualizing primary brain tumors. Purpose The aim of this study was re-evaluated the role of 13N-NH3 PET in brain tumor. Methods 13N- NH3 PET was performed in 47 patients (30male and 17 female patients;age range 18-62 years ) with suspected primary brain tumor or recurrent tumor detected by MRI. Five minutes after injection of 555-740 MBq of 13N-13N-NH3, attenuation-corrected brain images were obtained with a dedicated PET scanner. A histopathological diagnosis was made for 39 of them by open surgery or stereotatic biopsy, and the others were confirmed by clinical or radiologic follow-up, including 10 cases with astrocytoma grade Ⅰ or Ⅱ, 15 astrocytomas grade Ⅲ or Ⅳ(7 of them were tumor recurrence), 2 oligodendroglioma grade Ⅰ, 1 dysembryoplastic neuroepithelial tumor (DNT), 2 meningiomas, 2 metastatic tumors, 5 radiation necrosis, 7 encephalomyelitic foci, 2 ischemic lesions, 1 reactive gliosis. PET images were visually inspected, and the uptake ratios of lesion to contralateral normal brain tissue (T/N) were determined. Results Twenty-seven of thirty-two brain tumor exhibited markedly increased uptake of 13N-NH3. 2 oligodendroglioma, 1 DNT, 1 metastatic tumors and one low-grade astrocytoma in brain stem showed absent 13N-NH3 uptake. The 15 non-neoplastic lesions exhibited absent or less 13N-NH3 uptake. The sensitivity and specificity of 13N- NH3 PET for detecting brain tumor were 27 (84%) of 32 and 15 (100%) of 15, respectively. The sensitivity for detecting astrocytoma was 24 (96%) of 25. There were the significant differences between the T/N ratios in brain tumors and that in non-neoplastic lesions (T/W ratios

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眼科学报 1992年第1期8卷 8-11页

作者： Qingjiong Zhang, Wenshu Mao, Qiaoyun Ma, Ruiping Zeng , Lezheng Wu, De-Zheng Wu, Youzhao Chen Eye Research Institute, zhongshan Ophthalmic Center, sun yat-sen university of Medical Sciences guangzhou 510060, china.~+department of Medical Genetics, SUMS, guangzhou 510080, china. Eye Research Institute Sun Yat-sen University of Medical Sciences Guangzhou China.

According to the fact that the abnormalities of visual pigment genes were always involved in the changing of the exon 5, two oligonucleotide primers were designed to amplify the exon 5 of red pigment gene and green pigment gene. After electrophoresis of the PCR products digested with Rsal or Sau3A, the DNA fragments from the exon 5 of red pigment gene (RPG) and green pigment gene (GPG) were separated since there are different restriction endonuclease sites. On the other hand, we analyzed the exon 5 rela...

关键词： Color vision defect Gene Polymerase chain reaction Nucleic acid hybridization Heredity.

RING PROXY SIGNATURES

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Journal of Electronics(china) 2008年第1期25卷 108-114页

作者： Wei Baodian Zhang Fangguo Chen Xiaofeng department of Electronics and Communication Engineering Sun Yat-Sen University Guangzhou 510275 China department of Computer Science Sun Yat-Sen University Guangzhou 510275 China Guangdong.Key Laboratory of Information Security Technology Guangzhou 510275 China

Proxy signatures have been used to enable the transfer of digital signing power within some context and ring signatures can be used to provide the anonymity of a signer. By combining the functionalities of proxy signatures and ring signatures, this paper introduces a new concept, named ring proxy signature, which is a proxy signature generated by an anonymous member from a set of potential signers. The paper also constructs the first concrete ring proxy signature scheme based on the provably secure Schnorr's signatures and two ID-based ring proxy signature schemes. The security analysis is provided as well.

关键词： Proxy signature Ring signature Ring proxy signature ID-based cryptography Bilinear parings

Microvascular Changes in the Retrobulbar Optic Nerve in Idiopathic Intracranial Hypertension

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眼科学报 1999年第1期15卷 7-12页

作者： Xinzu Gu, X.H. Lin, H.G. Saddati, Y.Zhong, H.Y.Hsu, A.A.Sadunzhongshan Ophthalmic Center, sun yat-sen university of Medical Sciences, guangzhou 510060 , china department of Ophthalmology, USC school of medicine , Doheny Eye Institute, Los Angeles , CA 90033 Correspondence: Xinzu Gu, MD, PhD, zhongshan Ophthalmic Center, sun yat-sen university of Medical Sciences, 54 Xianlie Road, guangzhou 510060, china zhongshan Ophthalmic Center Sun Yat-sen University of Medical Sciences 54 Xianlie Road Guangzhou 510060 China

Purpose : To examine the microvascular changes in the retrobulbar optic nerve in idio-pathic intracranial hypertension (PTC).Methods: Both optic nerves from a 29-year-old man with a two year history of PTC were examined histologically and morphometrically. A semi-automated image analysis system and paraphenylenediamine (PPD) stain were employed to resolve sufficiently the microvascular images for counts and ***: There were 150 vessels distributed in the optic nerves which revealed the following: The average lumen of the vessels in outer sectors were larger than those of the inner sector vessels (168. 17μm2vs. 46. 99μm2; p = 0. 0338;OD; and 251. 96μm2vs. 130.02μm2;p = 0.029;OS) while in the normal control optic nerve the outer and inner area lumens were reversed in size-differential, but this did not show a statistical difference. The thickness of the PTC optic nerve vessel walls in the outer sectors was also greater than that of the walls in the inner sectors (4. 95μm vs. 2. 67μm;

关键词：神经微脉管轴突退化原发性颅骨内高血压

An Aggregation Composition Compensation Method Based on Paired Net

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International Journal of Automation and computing 2012年第5期9卷 530-538页

作者： Xiao-Yong Mei 1,2 Yi-Yan Fan 2 Chang-Qin Huang 3 Ai-Jun Jiang 1 Shi-Xian Li 1 1 school of Information Science and Technology,sun yat-sen university,guangzhou 510006,china 2 school of Computer Science and Technology,Hunan university of Arts and Science,Changde 415000,china 3 department of Electrical Engineering and Computer Science,university of California,Irvine,CA,92697,USA school of Information Science and Technology Sun Yat-sen University Guangzhou China school of Computer Science and Technology Hunan University of Arts and Science Changde China department of Electrical Engineering and Computer Science University of California Irvine USA

With regard to the failure and cancellation of business logic of web services composition(WSC),this paper propose a novel web services transaction compensation mechanism based on paired net which can dynamically establish agile compensation-triggered process(CSCP-Nets),and satisfy prospective compensation *** related execution semantics of five usual composition compensation patterns based on paired net are analyzed in the situations of successful execution,failure compensation and failure *** net based application of trip reservation process(TRP) shows that it is feasible.

关键词： Web services composition failure handling composition compensation execution semantic analysis paired net

The Inhibitory Effect of Extracts From Fructus lycii and Rhizoma polygonati on in vitro DNA Breakage by Alternariol

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Biomedical and Environmental Sciences 1996年第1期9卷 67-70页

作者： XU DAO-SONG KONG TIAN-QING AND MA JIAN-QUAN (department of Biochemistry, sun yat-sen university of Medical Sciences, guangzhou, 510089, Guangdong Province, china) department of Biochemistry Sun Yat-Sen University of Medical Sciences Guangzhou China.

Alternariol caused DNA single-strand breakage. Conversion of the closed circular double-stranded supercoiled DNA (pBR 322) to the nicked circular form and linear form was used to investigate the effect of extracts of some Chinese medical herbs on DNA nicking induced by alternariol. Some substances in the extracts of Rhizoma polygonati (RP) and Fructus lycii (FL) were shown to protect DNA from the attack by *** substance in the RP may bind to plasmid DNA, and this binding reduces the electrophoretic mobility of DNA. These results indicate that substances from FL and RP may be used as DNA protectors. It is possible that they play an important role in preventing cancer.

关键词： DNA The Inhibitory Effect of Extracts From Fructus lycii and Rhizoma polygonati on in vitro DNA Breakage by Alternariol

Fibrin(ogen)olytic character of Flla isolated from Agkistrodon acutus venom

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Acta Pharmacologica Sinica 2005年第6期 691-695页

作者： Yi-wen WANG, Xiu-xia LIANG, Jia-shu CHEN~2, Qi CHEN, Peng-xin QIU, Xi LIN, Guang-mei YAN department of Pharmacology, zhongshan Medical College, sun yat-sen university, guangzhou 510080, china

Aim: To investigate the fibrin(ogen)olytic character of FIIaisolated from Agkistrodon acutus venom in vitro and in vivo. Methods:125I-labeled human plasma clot lysis was measured in vitro and rabbit carotid artery thrombosis was as an in vivo model. Results: In vitro, urokinase (UK) at 25,35,40,45,60 kU/L and FTL, at 0.08,0.23,0.4,0.5, and 0.7 g/L resulted an equivalent clot lysis (20%, 40%, 50%, 60%, and 80%). UK at 25-60 kU/L induced 27.3%3.6%, 35.2%2.3%, 39.3%2.4%, 44.2%4.6%, and 51.1%1.2% fibrinogen degradation. But FIIaat 0.08-0.7 g/L induced 95.4%0.3%, >95.6%, >95.6%, >95.6%, >95.6% fibrinogen degradation respectively. In vivo, UK 40 kU/kg and FIIa1.0 mg/kg reduced the weight of residual thrombus to 9.02.5 mg and 7.83.5 mg compared with negative control group (30.05.4 mg). But the fibrinogen degradation rate after UK 40 kU/kg and FIIa1.0 mg/kg treatment was 24.4%6.2% and 4.1%7.8%, respectively (Pthe whole blood clots>platelet rich plasma (PRP) clots. The sequence for FIIa0.4 g/L was PRP>PPP>whole blood clots. Conclusion: At the same percentage of clot lysis, FIIadegraded more fibrinogen than UK did in vitro but less fibrinogen than UK did in vivo. The order of the lysis speed was PPP>whole blood clots>PRP clots for UK and PRP>PPP>whole blood clots for FIIa.

关键词： snake venoms Agkistrodon acutus urokinase fibrinolysis carotid artery thrombosis