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BL02U1:the relocated macromolecular crystallography beamline at the Shanghai Synchrotron Radiation Facility
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作者 Ke Liu Huan Zhou +9 位作者 Qin Xu Hua‑Ting Kong Kun‑Hao Zhang Wei‑Wei Wang Min‑Jun Li Zhi‑Jun Wang Qiang‑Yan Pan Xing‑Ya Wang Feng Yu Qi‑Sheng Wang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第12期146-155,共10页
Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focus... Macromolecular crystallography beamline BL17U1 at the Shanghai Synchrotron Radiation Facility has been relocated,upgraded,and given a new ID(BL02U1).It now delivers X-rays in the energy range of 6–16 keV,with a focused beam of 11.6μm×4.8μm and photon flux greater than 1012 phs/s.The high credibility and stability of the beam and good timing synchronization of the equipment significantly improve the experimental efficiency.Since June 2021,when it officially opened to users,over 4200 h of beamtime have been provided to over 200 research groups to collect data at the beamline.Its good performance and stable operation have led to the resolution of several structures based on data collected at the beamline. 展开更多
关键词 macromolecular crystallography beamline Shanghai Synchrotron Radiation Facility BL02U1
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Curcumin suppresses gastric NF-κB activation and macromolecular leakage in Helicobacter pylori-infected rats 被引量:28
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作者 Kawiya Sintara Duangporn Thong-Ngam +2 位作者 Suthiluk Patumraj Naruemon Klaikeaw Tanittha Chatsuwan 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第32期4039-4046,共8页
AIM:To investigate whether curcumin could attenuate nuclear factor(NF)-κB p65 expression and macromolecular leakage in the gastric mucosa of Helicobacter pylori(H.pylori)-infected rats.METHODS:Twenty-five male Spragu... AIM:To investigate whether curcumin could attenuate nuclear factor(NF)-κB p65 expression and macromolecular leakage in the gastric mucosa of Helicobacter pylori(H.pylori)-infected rats.METHODS:Twenty-five male Sprague-Dawley rats were equally divided into five groups:control rats(Control),control rats supplemented with 600 mg/kg curcumin,H.pylori-infected rats(Hp),H.pylori-infected rats supplemented with 200 mg/kg curcumin(Hp + curIn H.pylori-infected groups,rats were inoculated with H.pylori suspension twice a day at an interval of 4 h for 3 d.Two weeks later,200 or 600 mg/kg curcumin was given once daily to curcuminsupplemented groups for 7 d.On the day of the experiment,macromolecular leakage in gastric mucosa was examined by intravital fluorescence microscopy.The stomach tissue was removed to examine NF-κB p65 expression in gastric epithelial cells by immunohistochemistry.RESULTS:The expression of NF-κB p65 in gastric epithelial cells and the macromolecular leakage from gastric mucosal microcirculation significantly increased in the Hp group compared with the Control group.The percentages of NF-κB p65 immunoreactive cells in Control and Hp groups were 10.72% ± 2.10% vs 16.02% ± 2.98%,P = 0.004,respectively.The percentages of macromolecular leakage in Control and Hp groups were 10.69% ± 1.43% vs 15.41% ± 2.83%,P = 0.001,respectively.Curcumin supplementation in Hp + cur-CONCLUSION:H.pylori-induced gastric inflammation in rats is associated with increased NF-κB activation and macromolecular leakage which can be reduced by curcumin supplementation. 展开更多
关键词 CURCUMIN Helicobacter pylori Nuclear factorκB p65 macromolecular leakage
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Upgrade of macromolecular crystallography beamline BL17U1at SSRF 被引量:8
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作者 Qi-Sheng Wang Kun-Hao Zhang +10 位作者 Yin Cui Zhi-Jun Wang Qiang-Yan Pan Ke Liu Bo Sun Huan Zhou Min-Jun Li Qin Xu Chun-Yan Xu Feng Yu Jian-Hua He 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第5期58-64,共7页
Beamline BL17 U1 at Shanghai Synchrotron Radiation Facility is an energy-tunable macromolecular crystallography beamline that has been in user operation since 2009. Growing demand from the user community for a small b... Beamline BL17 U1 at Shanghai Synchrotron Radiation Facility is an energy-tunable macromolecular crystallography beamline that has been in user operation since 2009. Growing demand from the user community for a small beam and related experimental methods have motivated upgrades of the devices in the endstation.Minibeam modes have already been developed for operation. A self-integrated diffractometer reduces the sphere of confusion of the rotatory axis to 1μm. The new diffractometer is equipped with an upgraded on-axis viewing system that can improve the resolving power. Additionally,the area detector was also upgraded to the newest generation of detectors, the EIGER X 16 M, which can collect data at 133 Hz. After these upgrades, the endstation became virtually new. This paper covers the upgrade of the endstation devices and gives the first data collection results. 展开更多
关键词 Shanghai Synchrotron Radiation Facility macromolecular CRYSTALLOGRAPHY Endstation GONIOMETER Fine-phi SLICING
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Response of Macromolecular Structure to Deformation in Tectonically Deformed Coal 被引量:8
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作者 LI Xiaoshi JU Yiwen +1 位作者 HOU Quanlin FAN Junjia 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第1期82-90,共9页
The structural evolution of tectonically deformed coals (TDC) with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction (XRD) analysis on 3... The structural evolution of tectonically deformed coals (TDC) with different deformational mechanisms and different deformational intensities are investigated in depth through X-ray diffraction (XRD) analysis on 31 samples of different metamorphic grades (R : 0.7%-3.1%) collected from the Huaibei coalfield. The results indicated that there are different evolution characteristics between the ductile and brittle deformational coals with increasing of metamorphism and deformation. On the one hand, with the increase of metamorphism, the atomic plane spacing (d002) is decreasing at step velocity, the stacking of the BSU layer (Lc) is increasing at first and then decreasing, but the extension of the BSU layer (La) and the ratio of La/Lc are decreasing initially and then increasing. On the other hand, for the brittle deformational coal, d002 is increasing initially and then decreasing, which causes an inversion of the variation of Lc and La under the lower-middle or higher-middle metamorphism grade when the deformational intensity was increasing. In contrast, in the ductile deformational coals, d002 decreased initially and then increased, and the value of L~ decreased with the increase of deformational intensity. But the value of La increased under the lower-middle metamorphism grade and increased at first and then decreased under the higher-middle metamorphism grade. We conclude that the degradation and polycondensation of TDC macromolecular structure can be obviously impacted during the ductile deformational process, because the increase and accumulation of unit dislocation perhaps transforms the stress into strain energy. Meanwhile, the brittle deformation can transform the stress into frictional heat energy, and promote the metamorphism and degradation as well. It can be concluded that deformation is more important than metamorphism to the differential evolution of the ductile and brittle deformational coals. 展开更多
关键词 tectonically deformed coal X-ray diffraction deformational mechanism deformationalintensity macromolecular structure
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Synthesis and characterization of miktoarm star copolymer of styrene and butadiene using multifunctional macromolecular initiator 被引量:2
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作者 Hai Yan Zhang Xing Ying Zhang 《Chinese Chemical Letters》 SCIE CAS CSCD 2009年第9期1131-1135,共5页
A new kind of multifunctional macromolecular initiator with Sn-C bonds and polydiene arms was synthesized by living anionic polymerization. At first, polydiene-stannum chloride (PD-SnCl3) was prepared by the reactio... A new kind of multifunctional macromolecular initiator with Sn-C bonds and polydiene arms was synthesized by living anionic polymerization. At first, polydiene-stannum chloride (PD-SnCl3) was prepared by the reaction of n-butyl-Li (n-BuLi), stannic chloride (SnCl4) and diene. Then PD-SnCl3 was used to react with the dilithium initiator to prepare the multifunctional organic macromolecular initiators. The result suggested that the initiators had a remarkable yield by GPC, nearly 90%. By using these multifunctional macromolecular initiators, styrene and butadiene were effectively polymefized via anionic polymerization, which gave birth to novel miktoarm star copolymers. The relative molecular weight and polydispersity index, microstructure contents, copolymerization components, glass transition temperature (Tg) and morphology of the miktoarm star copolymers were investigated by GPC-UV, ~H NMR, DSC and TEM, respectively. 2009 Xing Ying Zhang. Published by Elsevier B.V. on behalf of Chinese Chemical Society. All rights reserved. 展开更多
关键词 Mnitifunctional macromolecular initiator Miktoarm star copolymer STYRENE BUTADIENE ISOPRENE Anionic polymerization
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Photoinitiating Characteristics of Benzophenone Derivatives as Type II Macromolecular Photoinitiators Used for UV Curable Resins 被引量:2
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作者 CHENG Liang-liang ZHANG Yong SHI Wen-fang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第1期145-149,共5页
Dodecyl-benzophenone(DBP) and hexadecoxyl-benzophenone(HDBP) as type 11 photoinitiators used for radical photopolymerization systems were synthesized by Friedel-Crafts reaction, and characterized by 1H NMR and FTI... Dodecyl-benzophenone(DBP) and hexadecoxyl-benzophenone(HDBP) as type 11 photoinitiators used for radical photopolymerization systems were synthesized by Friedel-Crafts reaction, and characterized by 1H NMR and FTIR spectroscopy. The UV-Vis absorption spectra of DBP and HDBP, propitious to photopolymerization under a commercial mercury UV bulb are centered at 345 and 335 nm, respectively. HDBP has higher extinction coefficient than DBP, but lower photoinitiating efficiency. Their photoinitiating performances for EB605, a bisphenol A epoxy acrylate with 40%(mass fraction) tripropyleneglycol diacrylate (TPGDA), resin consisting of bisphenol A epoxy acrylate and tripropyleneglycol diacrylate in the presence of triethanolamine as a coinitiator were investigated by photo-differential scanning calorimetry(photo-DSC). DBP initiates the curing of acrylate more efficiently than HDBP, showing higher photopolymerization rate and unsaturation conversion, resulted from the poor compatibility of HDBP with the resin. The photoinitiating activity of DBP to epoxy acrylate resin is even higher than that of BP at lower loadings. 展开更多
关键词 macromolecular photoinitiator Benzophenone derivative PHOTOPOLYMERIZATION
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Adsorption kinetics of platinum group elements onto macromolecular organic matter in seawater 被引量:1
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作者 Kai Liu Xuelu Gao +1 位作者 Qianguo Xing Fushan Chen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2019年第8期8-16,共9页
Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum... Adsorption kinetics of the interaction between Pt, Pd and Rh(defined here as platinum group elements, PGEs)ions and macromolecular organic compounds(MOCs,>10 kDa), including humic acid, carrageenan and bovine serum albumin, and different cutoff fractions of natural organic matter(>1 kDa and >3 kDa) obtained from seawater using centrifugal ultrafiltration devices were investigated. For a given element, all the adsorption kinetics did not reach equilibrium except the interaction between Pt and >1 kDa cutoff, and between Pd and humic acid.For all the tested MOCs, the adsorption kinetics could be divided into two stages, a rapid adsorption process in the first 8 h and the desorption stage after the first 8 h until the equilibrium. The change trend of partition coefficient(log10Kd) values with experiment time was consistent with that of the kinetic curves. However, in the interaction between PGE ions and natural dissolved organic matter(NDOM), an obvious difference in the change trends of log10Kd and kinetic curves was observed. It indicated that the partition behavior of PGE ions interacting with NDOM in seawater was a combined effect of different organic constituents. The adsorption and log10Kd of PGEs in the >1 kDa NDOM fraction were higher and more stable than those in the >3 kDa NDOM fraction. The results also indicated that the 1–3 kDa NDOM may dominate the interaction between PGEs ions and NDOM. Moreover, no kinetic model could perfectly simulate the adsorption process. It indicated that the colloidal struction and morphology of MOCs or NDOM in seawater might be inhomogeneous. Hence, the interaction between PGE ions and organic matter in seawater was a complicated process and needs further research. 展开更多
关键词 adsorption KINETICS PLATINUM group elements macromolecular ORGANIC COMPOUNDS natural ORGANIC MATTER seawater
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A NEW UNSTEADY THREE DIMENSIONAL MODEL FOR MACROMOLECULAR TRANSPORT AND WATER FILTRATION ACROSS THE ARTERIAL WALL 被引量:1
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作者 HUANG Hao(黄浩) +1 位作者 WEN Gong-bi(温功碧) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2001年第10期1155-1172,共18页
A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mit... A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mitosis of endothelial cell of the arterial wall, the macromolecular transport happens surrounding the leaky cells. The arterial wall was divided into four layers: the endothelial layer, the subendothelial intima, the internal elastic lamina and the media for the convenience of research. The time-dependent concentration growth,the effect of the shape of endothelial cell and the effect of physiological parameters were analyzed. The analytical solution of velocity field and pressure field of water flow across the arterial wall were obtained; and concentration distribution of three macromolecules ; LDL,HRP and Albumin, were calculated with numerical simulation method. The new theory predicts, the maximum and distribution areas of time dependent concentration with round shape endothelial cell are both larger than that with ellipse-shape endothelial cell. The model also predicts the concentration growth is much alike that of a two-dimensional model and it shows that the concentration reaches its peak at the leaky junction where atherosclerotic formation frequently occurs and falls down rapidly in a limited area beginning from its earlier time growth to the state when macromolecular transfer approaches steadily. These predictions of the new model are in agreement with the experimental observation for the growth and concentration distribution of LDL and Albumin. 展开更多
关键词 UNSTEADY three-dimensional model flow ACROSS the ARTERIAL wall macromolecular TRANSPORTATION ATHEROSCLEROSIS concentration distribution
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Identification of Damage on Different Plants Caused by Botrytis cinerea and its Extracellular Macromolecular Toxin 被引量:2
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作者 Hu Hailin Dong Qionge +3 位作者 Wu Jia Huo Da Wang Yunyue Yang Hongyu 《Plant Diseases and Pests》 CAS 2013年第3期16-19,共4页
With Bowytis cinerea and its extracellular macromolecular toxins as the test materials, 30 speiees of plants belonging to 29 genera and 21 families were selected as the test plants to observe the infectivity of B. dne... With Bowytis cinerea and its extracellular macromolecular toxins as the test materials, 30 speiees of plants belonging to 29 genera and 21 families were selected as the test plants to observe the infectivity of B. dnerea and damage status of macromolecular toxins secreted by B. cinerea on plants. The resulsts showed that 17 species of plants were beth infected by B. cinerea and damaged by toxins, accounting for 56.7% of the total plants. Two species of plants could be neither infected by B. cinerea nor damaged by toxins. The study provided the reference for further understanding of pathogenic mechanism of plant pathogenic fungi toxins. 展开更多
关键词 Botrytis cinerea ExtraceUular macromolecular toxins Damage identification of plant
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Studies on Hepatocyte-Targeting Magnetic Resonance Imaging Macromolecular Contrast Media 被引量:1
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作者 FU Yan jun ZHUO Ren xi 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1997年第4期56-58,63,共7页
DTPA was covalently conjugated to the copolymer of L lysine and L tyrosine, then transchelated with Gd EDTA,the resultant polymer chelates were further reacted with 6 O bromoacetyl D galacto... DTPA was covalently conjugated to the copolymer of L lysine and L tyrosine, then transchelated with Gd EDTA,the resultant polymer chelates were further reacted with 6 O bromoacetyl D galactose or methyl lactobionyloxyacetate to give PLT(Gd DTPA) with galactose moiety as liver targeting group.These macromolecular MRI contrast agents were characterized by means of FT IR, ICP AES, elementary analyses and UV Vis spectrophotometry. Their in vitro relaxivity and liver targeting property in mice were also investigated. 展开更多
关键词 MRI macromolecular contrast media(MMCM) POLYLYSINE Hepatocyte targeting RELAXIVITY BIODISTRIBUTION
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COMP ARISON OF MACROMOLECULAR COMPONENT DISTRIBUTIONS IN OSTEOARTHRITIC AND HEALTHY CARTILAGES BY FOURIER TRANSFORM INFRARED IMAGING 被引量:1
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作者 JIANHUA YIN YANG XIA ZHIYAN XIAO 《Journal of Innovative Optical Health Sciences》 SCIE EI CAS 2013年第4期84-90,共7页
Fourier transform infrared imaging(FTIRI)was used to examine the depth-dependent content variations of macromolcular components,ollagen and protooglycan(PG),in osteoarthritic and healthy cartilages.Dried 6 pmm thick s... Fourier transform infrared imaging(FTIRI)was used to examine the depth-dependent content variations of macromolcular components,ollagen and protooglycan(PG),in osteoarthritic and healthy cartilages.Dried 6 pmm thick sections of canine knee cartilages were imaged at 6.25 pμrm pixel-size in FTIRI.By analyzing the infrared(IR)images and spectra,the depth dependence of characteristic band(sugar)intensity of PG show obvious difference bet ween the cartilage sections of(OA)and bealth.The result confimns that PG content decreases in the ostcoarthritic cartilage.However,no clear change occurs to collagen,suggesting that the OA influences little on the collagen content at early stage of OA.This observation will be helpful to further understand PG loss associated with pathological conditions in OA,and demonstrates that FIIRI has the po-tential to become an important analytical tool to identify early clinical signs of tissue degna-dation,such as PG loss even collagen disruption. 展开更多
关键词 macromolecular component OSTEOARTHRITIS articular cartilage Fourier transform infrared imaging(FTIRI)
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Anti-tumor activities of macromolecular fractions of fresh gecko vivo and their induction of Bel-7402 cell differentiation 被引量:5
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作者 Yuxia Wang Xiangxiang Gu +3 位作者 Hongmei Deng Di Geng Huaying Sun Chunmei Wang 《Journal of Traditional Chinese Medical Sciences》 2017年第4期328-335,共8页
Objective:To investigate the anti-tumor effect of macromolecular fractions of fresh gecko (M-AG) in vivo and their differentiation-inducing activity in Bel-7402 cells in vitro.Methods:An H22 hepatocarcinoma-bearing mo... Objective:To investigate the anti-tumor effect of macromolecular fractions of fresh gecko (M-AG) in vivo and their differentiation-inducing activity in Bel-7402 cells in vitro.Methods:An H22 hepatocarcinoma-bearing mouse model was used to evaluate the anti-tumor activity of M-AG samples.The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was applied to analyze cell viability.Cell morphology was observed by phase contrast microscopy.The quantity of the alpha-fetoprotein was detected by a radioimmunoassay.Chromatometry was used to assay the albumin quantity.Activities of alkaline phosphatase and γ-glutamyl trans-peptidase were measured by biochemical methods.Finally,western blotting was applied to assess proteins in the mitogen-activated protein kinase (MAPK) signaling pathway.Results:Macromolecular fractions of fresh gecko exerted a significant anti-tumor effect in mice.The inhibition rate of tumor growth was 63% in the moderate M-AG dose group.Cells treated with M-AG displayed a differentiated state.The treatment lowered alphafetoprotein secretion and significantly decreased the activities of γ-glutamyl trans-peptidase and alkaline phosphatase in Bel-7402 cells.In contrast,M-AG increased the amount of albumin in the cell culture medium.All biochemical indices demonstrated that M-AG induced Bel7402 cell differentiation.Western blotting showed no changes in the quantities of extracellular signal-regulated kinase (ERK) 1/2,p38MAPK,or c-Jun N-terminal protein kinase 1/2.However,M-AG significantly activated the phosphorylation of ERK1/2 in a dose-dependent manner.In addition,M-AG had no significant influence on the expression of nuclear factor-kappa B.Conclusion:Macromolecular fractions of fresh gecko has an anti-tumor activity in H22 hepatocarcinoma-bearing mice in vivo and inhibits Bel-7402 cell proliferation in vitro by inducing cell differentiation related to activation of ERK1/2. 展开更多
关键词 macromolecular FRACTIONS of FRESH GECKO H22 hepatocarcinoma-bearing mice ANTI-TUMOR activity Induced differentiation ERK1/2
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A NEW UNSTEADY THREE DIMENSIONAL MODEL FOR MACROMOLECULAR TRANSPORT AND WATER FILTRATION ACROSS THE ARTERIAL WALL
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作者 黄浩 温功碧 《应用数学和力学》 EI CSCD 北大核心 2001年第10期1043-1057,共15页
A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mit... A new unsteady three-dimensional convective-diffusive mathematical model for the transportation of macromolecules and water across the arterial wall was proposed . After the formation of leaky junctions due to the mitosis of endothelial cell of the arterial wall, the macromolecular transport happens surrounding the leaky cells. The arterial wall was divided into four layers: the endothelial layer, the subendothelial intima, the internal elastic lamina and the media for the convenience of research. The time-dependent concentration growth, the effect of the shape of endothelial cell and the effect of physiological parameters were analyzed. The analytical solution of velocity field and pressure field of water flow across the arterial wall were obtained; and concentration distribution of three macromolecules; LDL, HRP and Albumin, were calculated with numerical simulation method. The new theory predicts, the maximum and distribution areas of time dependent concentration with round-shape endothelial cell are both larger than that with ellipse-shape endothelial cell. The model also predicts the concentration growth is much alike that of a two-dimensional model and it shows that the concentration reaches its peak at the leaky junction where atherosclerotic formation frequently occurs and falls down rapidly in a limited area beginning from its earlier-time growth to the state when macromolecular transfer approaches steadily. These predictions of the new model are in agreement with the experimental observation for the growth and concentration distribution of LDL and Albumin. 展开更多
关键词 非定常三维模型 大分子传质 动脉粥样硬化 浓度分布 跨血管壁流动
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BLOOD FLOW AND MACROMOLECULAR TRANSPORT IN CURVED BLOOD VESSELS
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作者 魏兰 温功碧 谭文长 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2006年第9期1223-1231,共9页
A numerical analysis of the steady/pulsatile flow and macromolecular (such as LDL and Albumin) transport in curved blood vessels was carried out. The computational results predict that the vortex of the secondary fl... A numerical analysis of the steady/pulsatile flow and macromolecular (such as LDL and Albumin) transport in curved blood vessels was carried out. The computational results predict that the vortex of the secondary flow is time-dependent in the aortic arch. The concentration of macromolecule concentrates at the region of sharp curve, and the wall concentration at the outer part is higher than that at the inner part. Atherosclerosis and thrombosis are prone to develop in such regions with sharp flow. 展开更多
关键词 curved blood vessels blood flow macromolecular transport ATHEROSCLEROSIS
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NMR RELAXIVITY AND IMAGING OF NEUTRAL MACROMOLECULAR POLYESTER GADOLINIUM(Ⅲ)COMPLEXES
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作者 叶朝辉 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 1999年第5期471-475,共5页
Five neutral macromolecular polyester gadolinium (Ⅲ) complexes with pendant hydrophobic alkyland aromatic functional groups were prepared. The longitudinal relaxation rates of these complexes weremeasured. One of the... Five neutral macromolecular polyester gadolinium (Ⅲ) complexes with pendant hydrophobic alkyland aromatic functional groups were prepared. The longitudinal relaxation rates of these complexes weremeasured. One of these Gd (Ⅲ) complexes was chosen for the acute toxicity test and T_1-weighted imagingmeasurement. Preliminary results showed that. compared with Gd-DTPA. the neutral macromoleculargadolinium (Ⅲ) complexes provide higher T_1 relaxivity enhancement and longer function duration. 展开更多
关键词 Magnetic resonance imaging (MRI) Neutral contrast agent macromolecular gadolinium complexes RELAXIVITY Acute toxicity
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THE STEADY/PULSATILE FLOW AND MACROMOLECULAR TRANSPORT IN T-BIFURCATION BLOOD VESSELS
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作者 李丁 温功碧 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2003年第5期532-544,共13页
A numerical analysis of the steady and pulsatile, macromolecular(such as low density lipopotein (LDL), Albumin) transport in T-bifurcation was proposed. The influence of Reynolds number and mass flow ratio etc. parame... A numerical analysis of the steady and pulsatile, macromolecular(such as low density lipopotein (LDL), Albumin) transport in T-bifurcation was proposed. The influence of Reynolds number and mass flow ratio etc. parameters on the velocity field and mass transport were calculated. The computational results predict that the blood flow factors affect the macromolecular distribution and the transport across the wall, it shows that hemodynamic play an important role in the process of atherosclerosis. The LDL and Albumin concentration on the wall varies most greatly in flow bifurcation area where the wall shear stress varies greatly at the branching vessel and the atherosclerosis often appears there. 展开更多
关键词 T-bifurcation steady blood flow unsteady blood flow macromolecular transport pulsatile blood flow
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Study on the Characteristics of Macromolecular Chains of Cellulose in Dilute Solutions
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作者 鲁平 陈自力 +1 位作者 田原 刘兆峰 《Journal of China Textile University(English Edition)》 EI CAS 1999年第3期21-24,共4页
The characteristics of macromolecular chains of cellulose in dilute solutions are discussed. Viscometry was used for the measurement of the intrinsic viscosity [η] of four cellulose samples, which were respectively d... The characteristics of macromolecular chains of cellulose in dilute solutions are discussed. Viscometry was used for the measurement of the intrinsic viscosity [η] of four cellulose samples, which were respectively dissolved in the solvent Tri-ethylenediamine cadmium hydroxide Cadoxen (Cadoxen), Cupriethylenediamine hydroxide(Cuen), iron sodium tartrate complex(EWNN) and N,N-dimethylacetamide(DMAc)with lithium chloride(LiCI, 9% w/w). The intrinsic viscosity of the four solutions decreased in the following manner:[η]DMAc/LiCl】[η]EWNN】[η]Cuen】[η]Cadoxen. The stability of cellulose (Sample α-cellulose) dissolved in solvents Cuen and EWNN was tested by plotting the intrinsic viscosity vs. time. The values of Huggins constant K_H for the cellulose samples dissolved in solvents Cadoxen,Cuen,EWNN and DMAc/LiCl (9% w/w ) were calculated. 展开更多
关键词 CELLULOSE INTRINSIC VISCOSITY DILUTE solutions macromolecular CHAINS .
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Phase transition of DNA compaction in confined space: Effects of macromolecular crowding are dominant
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作者 陈尔坤 范洋涛 +3 位作者 赵光菊 毛宗良 周海平 刘艳辉 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第1期489-494,共6页
With a view of detecting the effects of macromolecular crowding on the phase transition of DNA compaction confined in spherical space,Monte Carlo simulations of DNA compaction in free space,in confined spherical space... With a view of detecting the effects of macromolecular crowding on the phase transition of DNA compaction confined in spherical space,Monte Carlo simulations of DNA compaction in free space,in confined spherical space without crowders and in confined spherical space with crowders were performed separately.The simulation results indicate that macromolecular crowding effects on DNA compaction are dominant over the roles of multivalent counterions.In addition,effects of temperature on the phase transition of DNA compaction have been identified in confined spherical space with different radii.In confined spherical space without crowders,the temperature corresponding to phase transition depends on the radius of the confined spherical space linearly.In contrast,with the addition of crowders to the confined spherical space,effects of temperature on the phase transition of DNA compaction become insignificant,whereas the phase transition at different temperatures strongly depends on the size of crowder,and the critical volume fraction of crowders pertains to the diameter of crowder linearly. 展开更多
关键词 macromolecular crowding Monte Carlo simulation DNA compaction phase transition
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Effect of Vector Density and Competence on Macromolecular Vector Transformation Efficiency
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作者 Hongni Qin Lanlan ZHANG 《Asian Agricultural Research》 2016年第12期81-84,88,共5页
To research the effects of vector quantity and competence on the positive cloning rate,with a known gene sequence but in the absence of DNA template,we artificially designed 26 primers to synthesize a target gene of 8... To research the effects of vector quantity and competence on the positive cloning rate,with a known gene sequence but in the absence of DNA template,we artificially designed 26 primers to synthesize a target gene of 835 bp in vitro using overlapping PCR technique. The whole experiment design with two factors and six levels( 36 combinations) was applied to study the effects of the vector density and competent cells on the macromolecular vector transformation efficiency. Based on the 1 500 ng target gene,the vector density grades were designed( 50,100,150,200,250,300 ng),and then the recombinant plasmids were transformed into Top10F',DH5,Stbl3,Epi400,JM108,SCSI. Results showed that the positive cloning rates of different vector amount from big to small were in the order of 200,250,300,150,100 and 50 ng.The maximum positive cloning rate of 200 ng reached 75%; and the average value was 28. 5%. The positive cloning rates of different competent cells from big to small were in the order of stbl3,Top10F',DH5,JM108,Epi400 and SCSI. Stbl3 was higher than other competent cells under any vector density,and its average positive cloning rate was 42. 4%. Both the vector density and competent cells had significant effects on the macromolecular vector transformation efficiency. The optimal combination was C4 with 200 ng vector density and Stbl3,the positive cloning rate of which could reach 75%. 展开更多
关键词 macromolecular vector Vector density COMPETENCE Transformation efficiency
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Studies on mitochondrial macromolecular syntheses in various organs of aging animals labeled with 3H-precursors as revealed by electron microscopic radioautography
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作者 Tetsuji Nagata 《Advances in Bioscience and Biotechnology》 2010年第4期241-262,共22页
In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 indi... In order to study the aging changes of intramitochondrial macromolecular synthesis in various organs of aging animals during the development and aging, 10 groups of developing and aging mice, each consisting of 3 individuals, total 30, from fetal day 19 to postnatal newborn at day 1, 3, 9, 14 and adult at month 1, 2, 6, 12 to 24 were injected with 3H-thymidine a DNA precurson, another 10 groups consisting of 3 individuals, total 30, were injected with 3H-uridine a RNA precursor, and another 10 groups of 30 individuals were injected with 3H-leucine a protein precursor, total 90 individuals. Then, all the animals were sacrificed 1 hr after the injections and the liver tissues, the lung tissues, the kidney tissues, the testis and ovary tissues, the adrenal tissues were taken out, fixed and processed for electron microscopic radioautography. On electron microscopic radioautograms obtained from each animal, ten photographs in respective groups, numbers of mitochondria per cell profile area, numbers of labeled mitochondria per cell and the mitochondrial labeling index (LI) labeled with 3H-thymidine showing DNA synthesis, LI labeled with 3H-uridine showing RNA synthesis, and LI labeled with 3H-leucine showing protein synthesis, in various organs, were counted and the results in various organs in respective aging groups were compared, respectively. From the results, it was demonstrated that the numbers of mitochondria in hepatocytes as well as in 3 zones of the adrenal cortex, the zona glomerulosa, fasciculata and reticularis of mice at various ages increased from fetal day 19 to postnatal month 1 due to development and aging of animals. On the other hand, the numbers of labeled mitochondria and the labeling indices of intramitochondrial DNA syntheses incorporating 3H-thymidine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 zones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. The numbers of labeled mitochondria and the labeling indices of intramitochondrial RNA syntheses incorporating 3H-uridine in hepatocytes and 3 ones of cortical cells increased from fetal day 19 to postnatal month 1 and decreased to month 24. Moreover, some other organs such as the lung and the testis were also review and discussed. From the results, it was shown that the activity of intramitochnodrial DNA synthesis, RNA synthesis, and protein synthesis in hepatocytes, adrenal cortical cells, pulmonary cells and testicular cells in developing and aging mice as well as some other organs increased and decreased due to development and aging. 展开更多
关键词 MITOCHONDRIAL macromolecular SYNTHESES AGING ANIMALS Labeled 3H-Precursors ELECTRON MICROSCOPIC Radioautography
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