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Chinese Journal of Biomedical Engineering(English Edition) 1998年第2期7卷 75-86页

作者： Wen Zongyao Song Lichua Lu Zhihong sun dagong(department of Medical Physics, Beijing Medical University, Beijing 100083,China) yan zongyi(department of Mechanics and Engineering SciencePeking University,Beijing 100871,China) don huanfu(department of h

Based on Mohandas＇ work, a new animal model of red blood cell(RBC) synchronous senescence in a near normal physiological conditions was proposed. Using this model,we studied the changes of RBC surface charge with the aging process. The results showed that its surface charge decreased with RBC agingprocess. Nevertheless,the regulation of the changes was not linear during RBC aging. The indexes of (DI)d and (DI)or describing RBC rheological behaviours duringits aging process were measured with a new Ektacytometry. It is demonstrated thatboth the indexes decreased with RBC aging,but the relationship was not linear. Thecharacteristics of the indexes displayed a common regularity of smaller alterationsin the first half period of RBC life span and greater alterations in the latter periodof RBC life span. It was also shown that the regulation of the changes for each individual index were not alike. The alterations of RBC mechanical properties duringlife span maight result from the influence of RBC shape, the properties of cytoplasm and membrane viscoelasity and the other factors during RBC aging.

关键词： erythrocyte senescence surface charge rheological properties

Driver Fatigue Detection System Based on Colored and Infrared Eye Features Fusion

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Computers, Materials & Continua 2020年第6期63卷 1563-1574页

作者： Yuyang sun Peizhou yan Zhengzheng Li Jiancheng Zou don hong School of Mathematical Sciences Capital Normal UniversityBeijing100048China School of Electrical and Control Engineering North China University of TechnologyBeijing100144China School of Sciences North China University of TechnologyBeijing100144China department of Mathematical Sciences Middle Tennessee State UniversityMurfreesboroTN 37132USA

Real-time detection of driver fatigue status is of great significance for road traffic *** this paper,a proposed novel driver fatigue detection method is able to detect the driver’s fatigue status around the *** driver’s face images were captured by a camera with a colored lens and an infrared lens mounted above the *** landmarks of the driver’s face were labeled and the eye-area was *** calculating the aspect ratios of the eyes,the duration of eye closure,frequency of blinks and PERCLOS of both colored and infrared,fatigue can be *** on the change of light intensity detected by a photosensitive device,the weight matrix of the colored features and the infrared features was adjusted adaptively to reduce the impact of lighting on fatigue *** samples of the driver’s face were recorded in the test *** training the classification model,the results showed that our method has high accuracy on driver fatigue detection in both daytime and nighttime.

关键词： Driver fatigue detection feature fusion colored and infrared eye features

神经氨酸酶对红细胞膜的剪切弹性模量和表面粘度的影响

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中国生物医学工程学报 2001年第1期20卷 33-37,60页

作者：谢利德姚伟娟孙大公喀蔚波文宗曜尚俊杰严宗毅北京医科大学物理教研室北京100083 北京大学力学工程科学系北京100871

神经氨酸酶 (唾液酸酶 )与红细胞发生生物化学作用 ,分别改变其作用时间和二者的相对作用剂量 ,以达到不同程度地去掉红细胞的表面电荷。用文宗曜、严宗毅等[1] 最近提出的一种测量红细胞膜剪切弹性模量及表面粘度的新方法新型激光衍... 详细信息

神经氨酸酶 (唾液酸酶 )与红细胞发生生物化学作用 ,分别改变其作用时间和二者的相对作用剂量 ,以达到不同程度地去掉红细胞的表面电荷。用文宗曜、严宗毅等[1] 最近提出的一种测量红细胞膜剪切弹性模量及表面粘度的新方法新型激光衍射法 ,分别测量经过各种处理的红细胞的小变形指数 (DI) d 和变形恢复过程即松弛过程中变形恢复到最大值 (DI) max一半的时间t0 .5(即变形恢复半时间 ) ,将测得的结果分别代入红细胞膜的剪切弹性模量 (E)公式和红细胞面粘度 (μm)公式。计算出经过各种处理后的红细胞的膜剪切弹性模量和表面粘度 ,并与正常对照组的相应参数作比较 ,发现二者之间存在明显差异 ,此差异随处理程度的增加而增大 ,表现出明显的量效关系。因此有力地证明了神经氨酸酶对红细胞作用后使其膜剪切弹性模量增大 ,表面粘度增大 ,同时也体现了新型激光衍射法在测量红细胞膜的剪切弹性模量和表面粘度时有很好的灵敏性 ,它与国外文献所报道的微吸管法和流室法测得的结果相近 ,但操作方便 ,省时、省力、造价低 ,因此具有更广泛的应用范围。

关键词：神经氨酸酶红细胞膜剪切弹性模量表面粘度

Fabrication of edge-curled petals-like covalent organic frameworks and their properties for extracting indole alkaloids from complex biological samples

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Journal of Pharmaceutical Analysis 2022年第1期12卷 96-103页

作者： Fanrong sun Ligai Bai Mingxue Li Changqing Yu haiyan Liu Xiaoqiang Qiao hongyuan yan College of Pharmaceutical Sciences Hebei UniversityBaoding071002HebeiChina Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of Ministry of Education Baoding071002HebeiChina Institute of Life Science and Green Development Hebei UniversityBaoding071002HebeiChina

In this study,a functionalized covalent-organic framework(COF)was first synthesized using porphyrin as the fabrication unit and showed an edge-curled,petal-like and well-ordered *** synthesized COF was then introduced to prepare porous organic polymer monolithic materials(POPMs).Two composite POPM/COF monolithic materials with rod shapes,referred to as sorbent A and sorbent B,were prepared in stainless steel tubes using different *** A and B exhibited relatively uniform porous structures and enhanced specific surface areas of 153.14 m;/g and 80.01 m;/g,*** prepared composite monoliths were used as in-tube solid-phase extraction(SPE)sorbents combined with hPLC for the on-line extraction and quantitative analytical *** alkaloids(from Catharanthus roseus *** and Uncaria rhynchophylla(Miq.)*** havil.)contained in mouse plasma were extracted and quantitatively analyzed using the online *** two composite multifunctional monoliths showed excellent clean-up ability for complex biological matrices,as well as superior selectivity for target indole *** validation showed that the RSD values of the repeatability(n=6)were≤3.46%,and the accuracy expressed by the spiked recoveries was in the ranges of 99.38%-100.91%and 96.39%-103.50%for vinca alkaloids and Uncaria alkaloids,***,sorbents A and B exhibited strong reusability,with RSD values≤5.32%,which were based on the peak area of the corresponding alkaloids with more than 100 *** results indicate that the composite POPM/COF rod-shaped monoliths are promising media as SPE sorbents for extracting trace compounds in complex biological samples.

关键词： Covalent organic frameworks Monolithic material Solid-phase extraction Alkaloids Biological samples

Cytochrome P450 enzymes mediated by DNA methylation is involved in deoxynivalenol-induced hepatoxicity in piglets

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Animal Nutrition 2022年第2期9卷 269-279页

作者： Aimei Liu Yaqin yang Jingchao Guo yan Gao Qinghua Wu Ling Zhao Lv-hui sun Xu Wang National Reference Laboratory of Veterinary Drug Residues and Key Laboratory for Detection of Veterinary Drug Residues Huazhong Agricultural UniversityMinistry of Agriculture(MOA)Wuhan430070China hubei hongshan Laboratory College of Animal Science and TechnologyHuazhong Agricultural UniversityWuhan430070China MOA Laboratory for Risk Assessment of Quality and Safety of Livestock and Poultry Products Wuhan430070China College of Life Science Yangtze UniversityJingzhou434025China

Deoxynivalenol(don)is an inevitable contaminant in animal feed and can lead to liver damage,then decreasing appetite and causing growth retardation in *** many molecular mechanisms are related to hepatoxicity caused by don,few studies have been done on cytochrome P450(CYP450)enzymes and DNA *** explore the role of CYP450 enzymes and DNA methylation in doninduced liver injury,male piglets were fed a control diet,or diet containing 1.0 or 3.0 mg/kg don for 4 *** significantly raised the activity of aspartate aminotransferase(AST),alanine aminotransferase(ALT),and glutamyl transpeptidase(GGT)(Phat don exposure increased the expression of CYP450 enzymes(such as CYP1A1,CYP2E1,CYP3A29)(Phe expression of nicotinamide N-methyltransferase(NNMT),galanin-like peptide(GALP)and insulin-like growth factor 1(IGF-1)(Phich DNA methylation affected the expression of these *** vitro study(human normal hepatocytes L02)further proved that don elevated the expression of CYP1A1,CYP2E1 and CYP3A4(Phibited cell growth in a dose-dependent manner,resulting in cell *** importantly,knockdown of CYP1A1 or CYP2E1 could alleviate don-induced growth inhibition by promoting IGF-1 *** together,increased CYP450 enzymes expression was one of the mechanisms of hepatoxicity and growth inhibition induced by don,suggesting that the decrease of CYP450 enzymes can antagonize the hepatoxicity in animals,which provides some value for animal feed safety.

关键词： Deoxynivalenol hepatoxicity Growth inhibition CYP450 enzyme DNA methylation Piglet

《增广贤文》中的纺织服饰信息源考及其文化内涵探析

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武汉纺织大学学报 2024年第1期37卷 18-23页

作者：王燕杨小明东华大学人文学院上海201620

目前《增广贤文》中关于纺织服饰的信息解读存在着一些误解,这些误解不利于中国传统文化和纺织文化的传播。文章基于文献考据和考古实物相结合的二维互证研究方法,对《增广贤文》中关于纺织服饰的信息进行再研究,研究认为:第一,“红粉... 详细信息

目前《增广贤文》中关于纺织服饰的信息解读存在着一些误解,这些误解不利于中国传统文化和纺织文化的传播。文章基于文献考据和考古实物相结合的二维互证研究方法,对《增广贤文》中关于纺织服饰的信息进行再研究,研究认为:第一,“红粉”并不是指红色的粉,而是指胭脂和粉妆。第二,“假缎染就真红色,也被旁人说是非”一句,其实是被人篡改了,“缎”应该是“饶”字,此句是一种反面警示教育,告诫即使有真本事也会被人诋毁。第三,“种麻得麻,种豆得豆”一句中的麻是指麻籽,而非麻纤维。第四,“会使不在家豪富,风流不用着衣多”“有钱堪出众,无衣懒出门”涉及“衣”的解读两句看似相互矛盾,但二句反映的是中国君子对于自己的内心强调的是淡然,对外则强调“光前裕后”,强调“礼”在生活中的重要,同时强调礼只有通过心才能起到作用。第五,“光阴似箭,日月如梭”一句,体现了中国古代的纺织与世界观、宇宙观的联系。第六,“一毫之恶,劝人莫作。一毫之善,与人方便”中的毫是重量单位。

关键词：《增广贤文》纺织服饰考辨文化内涵

Effects of tip-pruning treatment on source-sink regulation of Catharanthus roseus seedlings

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Journal of Forestry Research 2006年第4期17卷 326-328页

作者： GAO yang ZhANG Xue-ke GUO Xiao-rui sun yan-fei ZU Yuang-gang Key Laboratory of Forest Plant Ecology the Ministry of Education of China Northeast Forestry University Harbin 150040 P. R. China

Fifty cultivated Catharanthus roseus seedlings were selected for tip-pruning treatment and the effects of tip-pruning on seedling growth and source-sink regulation were investigated for revealing physiological mechanisms of plants. The results showed that tip-pruning treatment resulted in obvious inhibition of apical dominance and enhancement of branching numbers. The contents of soluble sugars, acid sucrose invertase activity (AI) had a great change in differently positional leaves of the seedling. The sink strength in tip leaves of seedlings dramatically declined after tip-pruning treatment, while that in the leaves at the middle and bottom of seedlings had no obvious changes. The inhibition of apical dominance of tip leaves of seedlings was caused by the diminished sink strength due to tip-pruning treatment,

关键词： Catharanthus roseus (L.) G. don Source-sink regulation Tip-pruning Apical dominance

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膜蛋白交联对红细胞膜变形性及流动性的影响

北京生物医学工程 2000年第2期19卷 96-100页

作者：孙大公施岩陈凯谢利德姚伟娟文宗曜北京医科大学血液流变学研究中心北京100083 承德医学院数学教研室承德067000

本文通过不同浓度戊二醛作用于红细胞膜。用新型激光衍射法测量了这些红细胞样品的弹性模量 E和膜粘度 μm。同时通过 DPh标记的萤光偏振法测定了这些红细胞膜的流动性 ,并采用 MSL标记的电子自旋共振波谱技术 (ESR)测量了红细胞膜蛋白... 详细信息

本文通过不同浓度戊二醛作用于红细胞膜。用新型激光衍射法测量了这些红细胞样品的弹性模量 E和膜粘度 μm。同时通过 DPh标记的萤光偏振法测定了这些红细胞膜的流动性 ,并采用 MSL标记的电子自旋共振波谱技术 (ESR)测量了红细胞膜蛋白运动性的变化 ,并取得了与新型激光衍射法一致的结果。发现膜蛋白构象发生改变 ,膜脂流动性下降 ,红细胞膜剪切弹性模量 (E)和表面粘度 (μm)均呈上升趋势 ,红细胞变形能力下降。

关键词：膜蛋白生物力学特性红细胞膜变形性

The effect of intravenous high-dose glucocorticoids and orbital decompression surgery on sight-threatening thyroid-associated ophthalmopathy

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International Journal of Ophthalmology(English edition) 2019年第11期12卷 1737-1745页

作者： Yun Wen Jian-hua yan The State Key Laboratory of Ophthalmology Zhongshan Ophthalmic Center Sun Yat-sen University

AIM: To report the effects of intravenous high-dose glucocorticoids(iv GC) and orbital decompression(OD) surgery for treatment of sight-threatening thyroid-associated ophthalmopathy(TAO).METhODS: A retrospective review of medical records from patients with sight-threatening TAO [definite or highly suspected dysthyroid optic neuropathy(don)] treated with iv GC(60 cases) and OD(25 cases) was conducted at the Zhongshan Ophthalmic Center between January 2001 and January 2009. Patients were initially treated with iv GC(iv GC group). If no significant improvement in visual function was obtained, they then received OD surgery(OD group). The pre-versus post-treatment efficacies of either iv GC or OD in these patients were assessed using several indices, including visual acuity, intraocular pressure, ocular alignment, ocular motility, and exophthalmos. RESULTS: Nighty-one eyes had definite don while 79 were considered to have highly suspected don. In the iv GC group, 51 individuals(85.0%) eventually demonstrated normal vision, while 10 patients(16.7%) demonstrated a reduction in deviation(Phowed slight improvements in ocular motility(Phowed varying reductions of exophthalmos(mean: 4.35±1.13 mm, Pht cases(32.0%) experienced an 8-15 PD reduction of deviation and ocular motility improved in 12 cases(48.0%), while 3 patients(12.0%) developed new-onset strabismus with diplopia post-surgically(Ph iv GC and OD show good therapeutic efficacy in the treatment of sight-threatening TAO. Thepresence of extremely poor eyesight(≥0.5 log MAR) was corrected in some patients with iv GC alone, thus sparing these patients from subsequent OD surgery. In patients who were refractory to steroids, subsequent OD surgery often provided satisfactory outcomes, however, new-onset strabismus with di

关键词： thyroid-associated ophthalmopathy dysthyroid optic neuropathy glucocorticoids orbital decompression orbital surgery

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政策调整对股票市场波动的影响

经济问题 2013年第9期 36-39,62页

作者：孙研王春艳西北大学经济管理学院陕西西安710100 西安交通大学经济与金融学院陕西西安710061

以利率调整、存款准备金率调整、货币供应量变动作为货币政策调整变量,以印花税调整和财政支出变动作为财政政策调整变量,来研究股票市场的波动,分析了单个政策调整对股票市场波动的影响和政策调整组合对股票市场波动的影响。研究发现,... 详细信息

以利率调整、存款准备金率调整、货币供应量变动作为货币政策调整变量,以印花税调整和财政支出变动作为财政政策调整变量,来研究股票市场的波动,分析了单个政策调整对股票市场波动的影响和政策调整组合对股票市场波动的影响。研究发现,单一货币政策中存款准备金率调整对股票市场波动性影响显著,而利率调整对股票市场波动性影响不显著。单一财政政策中印花税调整在中期对股票市场波动性影响显著。不考虑宏观经济指数变动时,只有利率调整对股票市场波动性的影响显著为负向,印花税调整和存款准备金率调整对股票市场波动性影响不显著;考虑宏观经济指数变动时,三个政策调整对股票市场波动性的影响不显著。不论是否考虑宏观经济景气指数的变动,财政支出变动对股票市场波动的影响显著负向,货币供应量变动对股票市场波动的影响显著为正。

关键词：政策调整股票市场波动货币政策财政政策