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121.
目的探讨采用股骨近端防旋髓内钉(PFNA)治疗不稳定股骨转子间骨折的临床疗效。方法2009 年1 月至2011
年3月采用PFNA 内固定治疗不稳定股骨转子间骨折患者96例,男56例,女40例;年龄59~95岁,平均77.6岁;左侧40例,右侧56例。致伤原因:平地跌倒72例,交通伤15例,高处坠落9例。骨折根据按Evans-Jensen分型:Ⅲ型61 例,Ⅳ型35例。均为闭合性骨折,受伤至手术时间3 ~16 d,平均5.1d。结果本组96 例患者术中出血100~300ml,平均120ml;手术时间40~80 min,平均51.0min。2例患者在术后2个月合并脑血管疾病死亡,剩余94 例均获随访,随访时间12~32个月,平均15.2个月。骨折愈合时间10~14周,平均11.2周。术后肺部感染4例,下肢深静脉栓塞2例。髋关节功能恢复程度参照Harris 评分:优55例,良31例,可6例,差2例,优良率91.5%。随访期间无手术部位感染、无髋内翻、内固定折断及骨折再移位,无螺旋刀片断裂、拔出和切出等并发症。结论 PFNA 具有手术时间短、创伤小、出血少、固定可靠和并发症少等优点,是一种有效治疗不稳定股骨转子间骨折的方法。 相似文献
122.
白藜芦醇抗过氧亚硝基及保护DNA作用 总被引:5,自引:0,他引:5
利用紫外-可见、荧光光谱法研究了白藜芦醇(resveratrol,Res)与过氧亚硝基阴离子(peroxynitrite anion,ONOO^-)的相互作用,利用电泳方法证实了Res能抑制ONOO^-引起的DNA损伤作用.结果表明Res与ONOO^-之间存在相互作用,并对ONOO^-引起的DNA损伤具有明显的保护作用,当Res浓度为0.05mmol/L时,有近50%的断链DNA恢复为超螺旋态;CO2能显著降低ONOO^-引起的DNA单链断裂,并能加强Res的保护作用,当Res浓度为0.05mmol/L时,对DNA损伤的保护由50%增加到71%. 相似文献
123.
采用GC—MS技术,利用2种不同极性的毛细管柱分析了羽裂蟹甲草挥发油的化学组成,确定了31种成分的化学结构与相对含量,结果表明其挥发油主要由单萜、氧化单萜和倍半萜组成,其中倍半萜的含量32.1%尤其显著α-姜烯(13.49%)、大牦牛儿烯D(10.76%)、α-蒎烯(8.54%)、顺式丁香烯(6.36%)、芳樟醇(6.16%)、β-月桂烯(4.89%)、顺式β-罗勒烯(4.40%)和顺式罗勒烯酮(3.58%)是其主要成分.同时采用滤纸片琼脂平板扩散法和肉汤稀释法测试了其挥发油对2种真菌和12种细菌(包括6种临床致病菌)的抗菌活性.结果表明挥发油对大部分微生物均具有很好的抗菌作用,尤其对酵母菌、革兰氏阳性菌作用更强,其最低抑菌浓度(MIC)为0.16~5.00g/L,最低杀菌浓度(MBC)为0.16~5.00g/L. 相似文献
124.
DNA分子在激光作用下的随机动力学研究 总被引:6,自引:0,他引:6
对激光与DNA分子相互作用的问题,着重考虑了随机力和阻尼作用,建立了DNA分子在激光作用下的Fokker-Planck方程(FPE)。分析了DNA分子系统的FPE势函数,对DNA遗传变异的随机不确定性现象进行了解释。定义了遗传信息态迁移率,发现影响信息态迁移率的大小是随机力、激光强度以及DNA分子本身的特性协同作用的结果。 相似文献
125.
Wang X Wu G Lu C Wang Y Fan Y Gao H Ma J 《Colloids and surfaces. B, Biointerfaces》2011,86(1):237-241
A novel zwitterionic polypeptide derivative, denoted as His-PAsp/PAsp, was successfully synthesized by amidation of Poly (α,β-L-aspartic acid) with L-histidine methyl ester. Turbidity, zeta potential and 1H NMR measurements were used to study the aggregation behaviors of His-PAsp/PAsp under different pH values. The modified polypeptide derivative composed of electro-negatively carboxylic and electro-positively imidazole residues randomly so as to bear opposite charges at pH values above or below the isoelectric point. When the zwitterionic polypeptide was coated on silicon wafer as a model substrate material, the absorption resistance of fibrinogen, a blood protein resulting in the blood coagulation cascade, on the coated surface was measured. It was found that the adsorption amount of fibrinogen on the polypeptide-coated surface depended on the dose of the polypeptide on silicon wafer. Obvious resistance of the fibrinogen adsorption on the polypeptide-coated surface was observed. Since its good biodegradability and superior anti-protein-fouling property, this pH-responsive zwitterionic polypeptide is a promising candidate for surface modification in many biomedical applications, including medical implants, drug delivery carriers, and biosensors. 相似文献
126.
Yaqin Zhang Yongjun Li Long Sui Guolin Lu Xiaoyu Huang 《Journal of polymer science. Part A, Polymer chemistry》2012,50(10):1890-1899
A series of new well‐defined amphiphilic graft copolymers containing hydrophobic poly(tert‐butyl acrylate) backbone and hydrophilic poly(ethylene oxide) side chains were reported. Reversible addition‐fragmentation chain transfer homopolymerization of tert‐butyl 2‐((2‐bromopropanoyloxy)methyl)acrylate was first performed to afford a well‐defined backbone with a narrow molecular weight distribution (Mw/Mn = 1.07). The target poly(tert‐butyl acrylate)‐g‐poly(ethylene oxide) (PtBA‐g‐PEO) graft copolymers with low polydispersities (Mw/Mn = 1.18–1.26) were then synthesized by atom transfer nitroxide radical coupling or single electron transfer‐nitroxide radical coupling reaction using CuBr(Cu)/PMDETA as catalytic system. Fluorescence probe technique was employed to determine the critical micelle concentrations (cmc) of the obtained amphiphilic graft copolymers in aqueous media. Furthermore, PAA‐g‐PEO graft copolymers were obtained by selective acidic hydrolysis of hydrophobic PtBA backbone while PEO side chains kept inert. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012 相似文献
127.
Chen Dong Xingfei Zheng Guolin Li Honglin Zhu Mingquan Zhou Zhongli Hu 《Applied biochemistry and biotechnology》2011,163(5):679-691
Two cytosolic copper–zinc superoxide dismutase (cytCuZnSOD) complementary deoxyribonucleic acid were achieved in Nelumbo nucifera (Elian). The active sites and common characteristics of cytCuZnSOD family were showed by homology modeling. The two recombinant
proteins expressed by PET-32a vector showed the similar SOD activity (89.94 ± 0.54 U/mg) and could maintain more than 90%
activity after incubation at 65°C. The subcellular location by green fluorescent protein revealed that these two isoforms
were all located in cytosol and nucleus. The cytCuZnSODs were expressed in various parts of N. nucifera, which were expressed highest in the leafstalks and young leaves and lowest in the roots. The cytCuZnSOD messenger ribonucleic acids isolated from wounded leaves significantly increased at 1.5 h after treatment (HAT) with the
highest expression at 3 HAT, after which the level decreased. 相似文献
128.
A new kind of bifunctional magnetic-fluorescent nanoparticles(NPs)with abundant carboxyls on the surface has been prepared by covalently combining glutathiose(GSH)-modified CdTe quantum dots(QDs)with Fe_3O_4@SiO_2NPs.The silica-coated Fe_3O_4NPs were functionalized with amino groups by(3-aminopropyl)triethoxysilane to provide Fe_3O_4@SiO_2-NH_2NPs,which was then chemically conjugated with GSH-modified CdTe QDs to form bifunctional magnetic-fluorescent NPs,Fe_3O_4@SiO_2-NH-CO-CdTe-QDs NPs.The properties and morphologies of Fe_3O_4@SiO_2-NH-CO-CdTe-QDs NPs were investigated by FTIR,X-ray diffraction,transmission electron microscopy(TEM),absorption and fluorescence spectroscopy and vibrating sample magnetometry.TEM images display that Fe_3O_4@SiO_2-NH-CO-CdTe-QDsNPs possess spherical core-shell structure with a uniform size about 50 nm.The bifunctional NPs were found to exhibit good magnetic and strong fluorescent properties favorable for their application in the detection of latent fingerprints.Furthermore,the carboxyls on the surface of NPs have good absorptions with water in air and the residues of fingerprints so as to not only avoid dust flying to protect the health of operators,but also improve the efficiency of detection. 相似文献
129.
130.
Jimin Xu Guolin Cheng Deyong Su Yantao Liu Xinyan Wang Yuefei Hu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2009,15(47):13105-13110
A novel palladium catalyzed direct ortho‐arylation of N‐phenacylpyridinium bromide was developed. The amazing N‐phenacyl group regioselectively activates the C? H bond of pyridine and automatically departs from the arylated products. A kinetic isotope effect study proved that the reaction went through a C? H‐bond activation pathway and 2,6‐diphenylpyridine was produced stepwise from 2‐phenylpyridine. 相似文献