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6A型肺炎球菌结合物分子大小对小鼠免疫原性的影响 预览
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作者 杨英英 张钰奇 +10 位作者 马凯凯 周海飞 李献林 杜娇 杨田瑶 乔瑞洁 王玺 任珍芸 苗鑫 刘爱萍 罗树权 《微生物学免疫学进展》 2019年第3期16-21,共6页
目的 比较不同分子大小的6A型肺炎球菌(serotype 6A Streptococcus Pneumoniae )结合物和佐剂吸附在小鼠体内免疫原性的影响。方法 通过乙酸水解降低6A型荚膜多糖的相对分子质量制备成水解物,水解物经1-氰基-4-二甲胺基吡啶四氟硼酸盐(C... 目的 比较不同分子大小的6A型肺炎球菌(serotype 6A Streptococcus Pneumoniae )结合物和佐剂吸附在小鼠体内免疫原性的影响。方法 通过乙酸水解降低6A型荚膜多糖的相对分子质量制备成水解物,水解物经1-氰基-4-二甲胺基吡啶四氟硼酸盐(CDAP)活化并与破伤风类毒素己二酸酰肼衍生物TT AH 结合,制备成结合物。用Sepharose 4 Fast Flow 纯化结合物,并根据化学检测结果将结合物分为 K D 0.0~0.2、 K D 0.2~0.4、 K D 0.4~0.6等3个组分,每个组分分别以磷酸铝佐剂吸附,将吸附前后的各个组分按照每针次每只小鼠0.2 μg分别免疫小鼠,并采用ELISA检测结合物在小鼠体内的抗体水平。结果 3种不同相对分子质量吸附前后的结合物在小鼠体内均能产生较高水平的抗体,各组2、3针之间具有明显的加强效应。在吸附组和未吸附组中,3种不同分子大小的结合物在小鼠体内产生抗体水平无明显差异。各组分佐剂吸附后的结合物血清抗体滴度高于未吸附组,但这种差异无统计学意义( P > 0.05)。结论 结合物的分子大小对小鼠体内抗体水平的产生没有明显影响;磷酸铝佐剂吸附对于不同分子大小的结合物在小鼠体内的免疫原性有一定的增强效应,但这种增强效应差异无统计学意义。 展开更多
关键词 6A型肺炎球菌荚膜多糖 结合物 分子大小 佐剂 免疫原性
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一种新型的紫杉烷生物素共轭物的制备
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作者 景云荣 王昌伟 《山东大学学报:理学版》 CAS CSCD 北大核心 2019年第7期35-41,共7页
生物素与肿瘤细胞表面的生物素受体结合,通过受体介导的内吞作用将共轭物摄入细胞内,二硫键在肿瘤细胞中能够开链,释放出活性物质,实现靶向性给药,从而大大降低传统化疗药物因缺乏对肿瘤细胞的选择性而引起的毒副作用。用巯基置换的方式... 生物素与肿瘤细胞表面的生物素受体结合,通过受体介导的内吞作用将共轭物摄入细胞内,二硫键在肿瘤细胞中能够开链,释放出活性物质,实现靶向性给药,从而大大降低传统化疗药物因缺乏对肿瘤细胞的选择性而引起的毒副作用。用巯基置换的方式,合成含有二硫键的连接链;用将羧酸基团转化为酰肼基团的方法,将生物素转化为生物素酰肼;选用具有抗多药耐药性的含氟紫杉烷SB-T-12854作为细胞毒分子;通过含有二硫键的连接链将含氟紫杉烷化合物SB-T-12854与生物素酰肼进行偶连,形成一种新型的紫杉烷生物素共轭物。 展开更多
关键词 靶向型给药系统 紫杉烷 生物素 共轭物
细菌鞭毛蛋白在Treg表位肽自身免疫性风湿病治疗中的应用前景
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作者 李梦梦 刘晓 +4 位作者 殷健 王珍 刘亚群 钱锋 徐沪济 《中华微生物学和免疫学杂志》 CAS CSCD 北大核心 2019年第9期710-714,共5页
用调节性T细胞(Treg)表位肽进行免疫、激发和诱导表位肽特异的Treg细胞,抑制过强的自身免疫应答,从而建立起新的免疫稳态,是一个很有前景的自身免疫性风湿病的治疗方案,然而小分子的表位肽通常很难在体内有效激发出表位肽特异的免疫应... 用调节性T细胞(Treg)表位肽进行免疫、激发和诱导表位肽特异的Treg细胞,抑制过强的自身免疫应答,从而建立起新的免疫稳态,是一个很有前景的自身免疫性风湿病的治疗方案,然而小分子的表位肽通常很难在体内有效激发出表位肽特异的免疫应答。细菌鞭毛蛋白是固有免疫系统的一种激动剂,在作为偶联载体时对偶联的抗原有极强的佐剂作用,在特定情况下能够激发和诱导Treg细胞。因此,如果将Treg细胞表位肽与细菌鞭毛蛋白共价偶联,偶联体应可通过鞭毛蛋白本身的作用,以及鞭毛蛋白对Treg细胞表位肽的佐剂作用,有效增强基于Treg细胞的免疫应答,从而增强对自身免疫性风湿病的免疫治疗效果。 展开更多
关键词 细菌鞭毛蛋白 Treg表位 自身免疫性风湿病 偶联体 疫苗效应
发芽糙米蛋白-葡聚糖共价接枝复合物的开发及其物理化学性能、乳液稳定性的评价 预览
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作者 王雪 侯占群 +3 位作者 苑鹏 柳嘉 段盛林 孙爱东 《食品科学》 EI CAS CSCD 北大核心 2019年第12期46-54,共9页
将发芽糙米蛋白(germinated brown rice protein,GBRP)和葡聚糖通过美拉德反应开发一种新型的乳化剂。使用傅里叶变换红外光谱仪和X射线衍射仪分析发芽糙米蛋白-葡聚糖共价复合物(germinated brown riceprotein-dextran conjugate,GBRP-... 将发芽糙米蛋白(germinated brown rice protein,GBRP)和葡聚糖通过美拉德反应开发一种新型的乳化剂。使用傅里叶变换红外光谱仪和X射线衍射仪分析发芽糙米蛋白-葡聚糖共价复合物(germinated brown riceprotein-dextran conjugate,GBRP-Dex Con)。结果表明,通过与葡聚糖共价结合,相比于GBRP,GBRP-Dex Con的溶解度提高了10%(pH 7.0);变性温度(122.2 ℃)提高了14.7 ℃(GBRP为107.5 ℃);GBRP-Dex Con清除DPPH自由基能力及总还原能力显著提高(P<0.05)。通过测定美藤果油乳状液的粒径及物理稳定性发现,GBRPDexCon在稳定乳状液比GBRP、发芽糙米蛋白-葡聚糖混合物(GBRP-Dex Mix)以及作为常规乳化剂的大豆分离蛋白更为有效。本方法制备的乳化剂GBRP-Dex Con具有优异的性能和应用到食品工业的潜力。 展开更多
关键词 发芽糙米蛋白 葡聚糖 共价复合物 粒径 物理化学稳定性
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古汉语同根字考 预览
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作者 李玉 《红河学院学报》 2019年第1期105-110,共6页
从王力所著《同源字典》中未注意的“同源字”中尚可发现并甄别出不少“同根字”。有些字在王力《同源字典》中虽已收录,但这些字还有另外的“语源义”,可以与另一些字构成一组一组的“同根字”。这些同源字也是考察的对象。文章还进行... 从王力所著《同源字典》中未注意的“同源字”中尚可发现并甄别出不少“同根字”。有些字在王力《同源字典》中虽已收录,但这些字还有另外的“语源义”,可以与另一些字构成一组一组的“同根字”。这些同源字也是考察的对象。文章还进行汉藏语历史比较研究,以此来对所构拟原始汉语及上古汉语mb-型复辅音声母及清鼻音声母m-加以验证。 展开更多
关键词 同源字 同根字 语源义 语根 语核 音韵学 汉藏语
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Additive-free non-fullerene organic solar cells with random copolymers as donors over 9%power conversion efficiency
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作者 Meimei Wu Laitao Shi +5 位作者 Yu Hu Lie Chen Ting Hu Youdi Zhang Zhongyi Yuan Yiwang Chen 《中国化学快报:英文版》 SCIE CAS CSCD 2019年第6期1161-1167,共7页
In this study, a series of random conjugated polymers (PBDB-TBTn) as donors were designed and synthesized. In these polymers, benzodithiophene unit with thiophene conjugated side chains (BDT) are donor part, and two d... In this study, a series of random conjugated polymers (PBDB-TBTn) as donors were designed and synthesized. In these polymers, benzodithiophene unit with thiophene conjugated side chains (BDT) are donor part, and two different content of benzo[1,2-c:4,5-c']dithiophene-4,8-dione (BDD) and difluorobenzothiadizole (BT) linked alkylthiophene are acceptor unit. Polymer solar cells (PSCs) were fabricated with ITIC as an acceptor, and over the power conversion efficiency (PCE) of 9%was obtained, with open circuit voltage (Voc) of 0.86 V, short-circuit current density (Jsc) of 16.84 mA/cm^2, and fill factor (FF) of 62.5%. These random conjugated polymers based solar cells are insensitive to solvent additives and thermal annealing. The performance of the device decreases gradually with the increasing of the proportion of fluorinated acceptor unit. The declining efficiency is due to the excessive fluorinated acceptor unit, which leads to over aggregated topography, destroys the effective charge transport pathways, and affects phase separation domain size between the donor and the acceptor. The phenomena are explained by the charge carrier recombination, atomic force microscope (AFM), and transmission electron microscope (TEM). These results indicate that proper addition of fluorinated acceptor units to build random copolymers can enhance the efficiency of organic photovoltaics toward additive-free and thermal annealing-free PSCs. 展开更多
关键词 Random conjugated POLYMER POLYMER solar cells Ternary CONJUGATE polymers Non-fullerene organic photovoltaics
Freezing on demand:A new concept for mine safety and energy savings in wet underground mines 预览
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作者 Mahmoud A.Alzoubi Ahmad Zueter +1 位作者 Aurelien Nie-Rouquette Agus P.Sasmito 《矿业科学技术学报:英文版》 CSCD 2019年第4期621-627,共7页
The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation area... The artificial ground freezing(AGF)systems are designed to operate continuously for an extended period of time to control the groundwater seepage and to strengthen the groundwater structure surrounding excavation areas.This mode of operation requires a massive amount of energy to sustain the thickness of the frozen body.Therefore,it is of great interest to propose new concepts to reduce energy consumption while providing sufficient structural stability and safe operation.This paper discusses the principle of the freezing on demand(FoD)by means of experiment and mathematical model.A lab-scale rig that mimics the AGF process is conceived and developed.The setup is equipped with more than 80 thermocouples,flow-meters,and advanced instrumentation system to analyze the performance of the AGF process under the FoD concept.A mathematical model has been derived,validated,and utilized to simulate the transient FoD concept.The results suggest that the overall energy saving notably depends on the coolant’s temperature;the energy saving increases while decreasing the coolant inlet temperature.Moreover,applying the FoD concept in an AGF system leads to a significant drop in energy consumption. 展开更多
关键词 Artificial ground FREEZING FREEZING on DEMAND Energy SAVING CONJUGATE heat transfer Porous media
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冻干b型流感嗜血杆菌结合疫苗强制降解的稳定性研究
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作者 孙晓东 张腾腾 +3 位作者 佟巍 刘翠 张静飞 刘建凯 《国际生物制品学杂志》 CAS 2019年第2期57-60,共4页
目的 通过强制降解试验观察冻干b型流感嗜血杆菌(Haemophilus in fluenzae type b, Hib)结合疫苗在高温、高湿、强光照射下的稳定性,为疫苗生产工艺、包装材料和贮存条件的确定提供科学依据.方法 分别采用40℃温度、(75±5)%相对湿... 目的 通过强制降解试验观察冻干b型流感嗜血杆菌(Haemophilus in fluenzae type b, Hib)结合疫苗在高温、高湿、强光照射下的稳定性,为疫苗生产工艺、包装材料和贮存条件的确定提供科学依据.方法 分别采用40℃温度、(75±5)%相对湿度、(4 500±500)lx光照处理冻干Hib结合疫苗,取样,按中国药典2015年版三部的要求进行疫苗的全部项目检测.结果 冻干Hib疫苗经40℃处理10d,水分由2.0%上升至2.9%,多糖分子大小(分配系数<0.2的洗脱液回收率)由94%下降至85%,但两者仍分别符合≤3.0%和>60%的质量标准;而高分子结合物含量由87%降至75%,已不符合≥80%的质量标准.(75±5)%相对湿度和(4 500±500) lx光照处理10d对疫苗的影响不明显,疫苗质量指标仍符合规定.结论 高温是影响冻干Hib结合疫苗稳定性的主要因素. 展开更多
关键词 嗜血菌 流感 b型 疫苗 结合 应力 物理 药物稳定性
A modified Tikhonov regularization method for a Cauchy problem of a time fractional diffusion equation 预览
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作者 CHENG Xiao-liang YUAN Le-le LIANG Ke-wei 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第3期284-308,共25页
In this paper,we consider a Cauchy problem of the time fractional diffusion equation(TFDE)in x∈[0,L].This problem is ubiquitous in science and engineering applications.The illposedness of the Cauchy problem is explai... In this paper,we consider a Cauchy problem of the time fractional diffusion equation(TFDE)in x∈[0,L].This problem is ubiquitous in science and engineering applications.The illposedness of the Cauchy problem is explained by its solution in frequency domain.Furthermore,the problem is formulated into a minimization problem with a modified Tikhonov regularization method.The gradient of the regularization functional based on an adjoint problem is deduced and the standard conjugate gradient method is presented for solving the minimization problem.The error estimates for the regularized solutions are obtained under Hp norm priori bound assumptions.Finally,numerical examples illustrate the effectiveness of the proposed method. 展开更多
关键词 CAUCHY problem time-fractional diffusion equation a MODIFIED Tikhonov REGULARIZATION METHOD CONJUGATE gradient METHOD error estimates
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NEW HYBRID CONJUGATE GRADIENT METHOD AS A CONVEX COMBINATION OF LS AND FR METHODS 预览
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作者 Snezana S.DJORDJEVIC 《数学物理学报:B辑英文版》 SCIE CSCD 2019年第1期214-228,共15页
In this paper, we present a new hybrid conjugate gradient algorithm for unconstrained optimization. This method is a convex combination of Liu-Storey conjugate gradient method and Fletcher-Reeves conjugate gradient me... In this paper, we present a new hybrid conjugate gradient algorithm for unconstrained optimization. This method is a convex combination of Liu-Storey conjugate gradient method and Fletcher-Reeves conjugate gradient method. We also prove that the search direction of any hybrid conjugate gradient method, which is a convex combination of two conjugate gradient methods, satisfies the famous D-L conjugacy condition and in the same time accords with the Newton direction with the suitable condition. Furthermore, this property doesn’t depend on any line search. Next, we also prove that, moduling the value of the parameter t,the Newton direction condition is equivalent to Dai-Liao conjugacy condition.The strong Wolfe line search conditions are used.The global convergence of this new method is proved.Numerical comparisons show that the present hybrid conjugate gradient algorithm is the efficient one. 展开更多
关键词 hybrid CONJUGATE GRADIENT method CONVEX combination Dai-Liao CONJUGACY condition NEWTON direction
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Enantioselective Conjugate Addition-Protonation of 5H-Oxazol-4-ones and 5-Methylene 1,3-Oxazolidine-2,4-diones: 2,2'-Biphenol-lnduced Diastereoselectivity Switch
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作者 Bohua Lu Shuang Xin +1 位作者 BO Zhu Junbiao Chang 《中国化学:英文版》 SCIE CAS CSCD 2019年第7期689-694,共6页
A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjuga... A synthetic strategy for catalytic asymmetric conjugate addition-protonation and diastereoselective switch between 5H-oxazol-4-ones and 5-methylene 1,3-oxazolidine-2,4-diones was established.An array of chiral conjugate addition-protonation products bearing 1,3-O-heterotertiary-O-heteroquarternary nonadjacent stereocenters were obtained in excellent yields,moderate to good diastereoselectivities,and excellent enantioselectivities (up to 97% yield,11:1 dr,and 98% ee).Induction by 2,2'-biphenol could effectively promote the production of the corresponding diastereoisomers via cycloaddition intermedia. 展开更多
关键词 Conjugate Addition DIASTEREOSELECTIVITY
用于穿透和聚焦在散射介质内部的光学相位共轭技术 预览
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作者 李承明月 《红外与激光工程》 EI CSCD 北大核心 2019年第7期1-9,共9页
Optical phase conjugation(OPC)is a technique that generates a light field with reversed wavefront and identical amplitude distribution as the incident light.It has a unique feature of suppressing the aberration of inc... Optical phase conjugation(OPC)is a technique that generates a light field with reversed wavefront and identical amplitude distribution as the incident light.It has a unique feature of suppressing the aberration of incident beam induced by inhomogeneous or disturbing medium.Although this technique has been extensively studied since the 1970s,it has become more attractive because of unprecedented achievements and prospective potentials in biomedical applications.OPC-based techniques have been successfully utilized to form a focus through/inside highly scattered biological samples.It opens a new avenue by significantly enhancing the light delivery in biological tissue for high-resolution imaging,diagnosis and treatment of medical diseases.In order to provide insight into its further development,recent progress of OPC techniques for focusing light through/inside biological tissue was summarized. 展开更多
关键词 optical PHASE CONJUGATION HOLOGRAPHY digital HOLOGRAPHY HOLOGRAPHIC material PHASE CONJUGATE mirror
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可拓学共轭理论在专利资源分析中的运用 预览
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作者 鄞汉藩 周彦 +5 位作者 陆碧虹 钟兵 陈亮 黄盼 韩丽平 林娜 《广东工业大学学报》 CAS 2019年第3期16-24,67共10页
本文采用虚部与实部的物质性、软部与硬部的系统性、潜部与显部的动态性、负部与正部的对立性4个方面的分析方法,研究专利事物之间相互对应以及相互关联的共轭关系,探求专利创造、保护、运用的各种矛盾问题的解决方法,开拓专利技术创新... 本文采用虚部与实部的物质性、软部与硬部的系统性、潜部与显部的动态性、负部与正部的对立性4个方面的分析方法,研究专利事物之间相互对应以及相互关联的共轭关系,探求专利创造、保护、运用的各种矛盾问题的解决方法,开拓专利技术创新之路,在潜在风险隐患进行未雨绸缪的专利预警中、在现有资源进行有深度宽度的专利挖掘中、在科技成果进行有力度速度的专利创造中、在世界市场进行有角度尺度的专利布局中、在未来发展进行有高度广度的专利导航中,进一步增强企业参与世界经济大循环的竞争力,实现专利应有的市场价值和社会价值. 展开更多
关键词 可拓学 专利 资源 分析 共轭 运用
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易卦与代数 预览
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作者 丁光涛 《安徽师范大学学报:自然科学版》 CAS 2019年第5期409-413,共5页
从代数学角度研究传统易卦符号体系,引入四象和八卦的共轭和乘积运算,并与复数和四元数乘积比较,指出可以构成不同于复数和四元数的新数系。
关键词 易卦 代数 数系 共轭 乘积
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沉水植物对阿特拉津胁迫的毒理响应 预览
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作者 瞿梦洁 朱锋 +2 位作者 李慧冬 刘伟 朱端卫 《生态毒理学报》 CSCD 北大核心 2018年第4期209-216,共8页
为揭示在阿特拉津胁迫下沉水植物生长及其与谷胱甘肽代谢途径的关系,通过培养实验研究了沉水植物菹草(Potamogeton crispus)和穗花狐尾藻(Myriophyllum spicatum)对0、0.5、1.0和2.0 mg·kg~(-1)阿特拉津的吸收特性,并对不同... 为揭示在阿特拉津胁迫下沉水植物生长及其与谷胱甘肽代谢途径的关系,通过培养实验研究了沉水植物菹草(Potamogeton crispus)和穗花狐尾藻(Myriophyllum spicatum)对0、0.5、1.0和2.0 mg·kg~(-1)阿特拉津的吸收特性,并对不同培养时期沉水植物的鲜重、总谷胱甘肽含量(T-GSH,即还原型谷胱甘肽GSH和氧化型谷胱甘肽GSSG之和)、GSH/GSSG比值及其形态变化、谷胱甘肽还原酶(GR)活性和谷胱甘肽-S-转移酶(GST)活性进行了测定。结果表明:沉积物阿特拉津初始浓度越高,植物体内阿特拉津浓度也越高。在培养60 d内,添加的阿特拉津对2种沉水植物的生长均产生显著抑制作用(P〈0.05)。在阿特拉津胁迫60 d后,各处理植物体内GSH/GSSG比值有所回升,其GR和GST活性均高于空白对照组。处理组植物体内GR和GST活性在30 d时达到最高值。与此同时,GSH脱去谷氨酸后能与阿特拉津形成共轭物。以上结果提示,≤2 mg·kg~(-1)阿特拉津在培养前60 d内会对植物生长产生抑制,但在90 d时植物会从伤害中恢复过来。沉水植物体内的谷胱甘肽在GR和GST作用下,对阿特拉津及其产生的活性氧具有一定去除作用,并通过控制酶活使植物体保持一定的GSH含量;另一方面,GSH可以与阿特拉津结合形成新的共轭物,以此缓解阿特拉津对沉水植物的毒害。 展开更多
关键词 阿特拉津 沉水植物 鲜重 谷胱甘肽 共轭物 谷胱甘肽还原酶 谷胱甘肽S-转移酶
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In vitro and in vivo evaluation of improved EGFR targeting peptide-conjugated phthalocyanine photosensitizers for tumor photodynamic therapy
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作者 Qingle Chen Yanhong Ma +6 位作者 Jisi Zhao Mei Zhao Wenjing Li Qian Liu Li Xiong Wenjie Wu Zhangyong Hong 《中国化学快报:英文版》 SCIE CAS CSCD 2018年第7期1171-1178,共8页
Phthalocyanine(Pc) is one of the most promising photosensitizer candidates because of its strong absorption(extinction coefficient ε 〉 10^5 LmoI -1 cm^-1) at long wavelengths and strong singlet oxygen generation... Phthalocyanine(Pc) is one of the most promising photosensitizer candidates because of its strong absorption(extinction coefficient ε 〉 10^5 LmoI -1 cm^-1) at long wavelengths and strong singlet oxygen generation abilities(a singlet oxygen quantum yield of approximately 50%). However, low tumor targeting, low water solubility and a high tendency to aggregate appear to significantly restrict the compound's application in tumor treatment. Conjugating Pc with peptide ligands could be a useful strategy for alleviating these problems. Here, to further optimize the structures of peptide-conjugated zinc Pcs for PDT therapy, we finely tuned the hydrophilicity of the modified Pc aromatic macrocycle with varied length of polyethylene glycol(PEG) and added an extra PEG linker and an extra glutamic acid between the Pc ring and the peptide ligand to reduce the influence of the ligand on the Pc aromatic ring.Among the synthesized conjugates, Pc-3 showed greatly improved targeting towards tumors and abolished inoculated tumors with only a single PDT treatment in a subcutaneous xenograft tumor model,making this approach a promising therapeutic agent for the treatment of cancer. 展开更多
关键词 Photodynamic therapy Potosensitizer PHTHALOCYANINE PEPTIDE CONJUGATE
氨苯砜-海藻酸缀合物的合成、表征及释放评价
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作者 范雪娇 张丽丽 葛志强 《中国药学杂志》 CSCD 北大核心 2018年第3期205-209,共5页
目的合成氨苯砜-海藻酸(DS—Alg)缀合物,确保氨苯砜(DS)无法经皮吸收进入全身血液循环。方法海藻酸(Alg)作为载体、缬氨酸(Val)为连接臂,合成DS—Alg缀合物并优化合成条件。^1H—NMR、MS以及FT—IR对产物结构进行确证。以pH7... 目的合成氨苯砜-海藻酸(DS—Alg)缀合物,确保氨苯砜(DS)无法经皮吸收进入全身血液循环。方法海藻酸(Alg)作为载体、缬氨酸(Val)为连接臂,合成DS—Alg缀合物并优化合成条件。^1H—NMR、MS以及FT—IR对产物结构进行确证。以pH7.4、0.05mol·L^-1PBS和乙醇混合液为接受介质,进行DS—Alg缀合物体外释放评价,监测释放介质中缬氨酸-氨苯砜(Val—DS)和DS的浓度。大鼠局部烫伤作为模型,对创伤部位涂抹给药,监测血液中药物浓度。结果优化得到DS—Alg合成条件为:缬氨酸一氨苯砜0.277g、海藻酸钠0.400g、1-(3-二甲氨基丙基)-3-乙基碳二亚胺盐酸盐7eq、N-羟基丁二酰亚胺3eq、反应溶剂pH为5.5。缀合物释放72h,接受液中无Val-DS或DS检出,表明DS与Alg共价结合后结构稳定,Ds在实验条件下无法解离透皮释放。DS—Alg经皮给药72h内大鼠血浆中无DS检出,AUC0→72h为0,说明缀合药物无法经皮肤进入血液。结论DS—Alg结构稳定,可以避免DS进入血液循环。 展开更多
关键词 氨苯砜 海藻酸 缀合物 局部用药 药物释放
Combretastatin A4/poly(L-glutamic acid)-graft-PEG conjugates self-assembled to nanoparticles 预览
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作者 Yang Ou Zhao-hui Tang +4 位作者 Lu Sun Hai-yang Yu Jia Li Mei-hui Zhao Hui Xu 《亚洲药物制剂科学(英文)》 2018年第2期191-196,共6页
Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficac... Combretastatin A4(CA4) possesses varying ability to cause vascular disruption in tumors,while the short half-life, low water solubility and deactivation of many CA4 analogs during storage limited its antitumor efficacy and drug stability. A novel macromolecular conjugate of CA4(CA4-PL) was synthesized by covalent bonding of CA4 onto poly(L-glutamic acid)-graft-polyethylene glycol(PLG-g-PEG) via Yamaguchi reaction. The obtained CA4-PL was characterized by ~1H NMR, GPC, and UV methods, and the properties of the nanoparticles composed of CA4-PL, including critical aggregation concentration, size and size distribution, and morphology, were investigated. CA4-PL can self-assemble to form micelle-like nanoparticles of 80~120 nm in diameter, which may have potential to improve the blood circulation period as well as the targetability of CA4, and find applications to treat various tumors when combined with traditional chemotherapy or radio therapy. 展开更多
关键词 COMBRETASTATIN A4 Macromolecular conjugate Poly(L-glutamic acid)-graft-polyethylene glycol SELF-ASSEMBLE NANOPARTICLES
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Self-immolative micellar drug delivery:The linker matters
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作者 Xuan Meng Min Gao +6 位作者 Jian Deng Di Lu Aiping Fan Dan Ding Deling Kong Zheng Wang Yanjun Zhao 《纳米研究:英文版》 SCIE EI CAS CSCD 2018年第12期6177-6189,共13页
Redox-responsive polymer-drug conjugate micelles are excellent nanoscale vehicles for self-immolative intracellular drug delivery.To covalently connect the polymer and drug,disulfide-bearing linkers,such as 3,3'-d... Redox-responsive polymer-drug conjugate micelles are excellent nanoscale vehicles for self-immolative intracellular drug delivery.To covalently connect the polymer and drug,disulfide-bearing linkers,such as 3,3'-dithiodipropionic acid (DDPA) and 4,4'-dithiodibutyric add (DDBA),are used.In this paper,we report the influence of linker length on the therapeutic outcome of redox-sensitive conjugate micelles.Curcumin was selected as the model drug and it was conjugated to a multivalent methoxy poly(ethylene glycol)-polylysine copolymer with DDPA or DDBA as the linker.The obtained two polymer-curcumin conjugates were amphiphilic and could self-assemble into micelles that have a hydrodynamic diameter less than 100 nm.The loading of curcumin in both micelles was above 20% (w/w).Irrespective of the linker type,micelle disassembly was observed due to the collapse of the disulfide bond in a reducing environment.However,the rate of curcumin release was much faster with the DDBA linker than with the DDPA linker as the side product was a 5-membered ring with a low ring strain.The linker length-induced variation of curcumin release kinetics caused a significant difference in the intracellular drug concentration and a higher cytotoxicity was witnessed in three model cell lines (HeLa,PC3,and 4T1) for the micelles with a DDBA linker compared to those containing a DDPA linker.As expected,this phenomenon was also observed in HeLa tumor-bearing nude mice in vivo.The current work highlights the significance of linker length in engineering redox-responsive on-demand delivery systems. 展开更多
关键词 DRUG delivery micelles redox-responsive CURCUMIN polymer-drug CONJUGATE
汉语同根字札记 预览
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作者 李玉 《龙岩学院学报》 2018年第3期27-34,共8页
从王力所著《同源字典》中未注意的同源字中尚可发现并甄别出不少"同根字"。有些字王力《同源字典》虽已收录,但这些字还有另外的"语源义",可以与另一些字构成一组一组的"同根词"。这些字也是考察的对象。在进行汉藏语历史比较研... 从王力所著《同源字典》中未注意的同源字中尚可发现并甄别出不少"同根字"。有些字王力《同源字典》虽已收录,但这些字还有另外的"语源义",可以与另一些字构成一组一组的"同根词"。这些字也是考察的对象。在进行汉藏语历史比较研究的基础上,对文中所构拟的原始汉语及上古汉语^**mb-型复辅音声母加以验证。 展开更多
关键词 同源词 同根词 语源义 语根 语核 汉藏语
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