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借助于等体积分割法计算了各结构组分的体积百分含量,定量考虑各个织构组分的贡献,并以近真ODF的简便算法消除其误差;结合连续体力学法得出的相应取向的塑性应变比预估了O8Al深冲钢板的r值。结果表明:预估值与实测值符合得较好。 相似文献
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鸭梨果实采后生理及其气调贮藏气体组分研究 总被引:5,自引:0,他引:5
鸭梨果实采后在20±1℃时,随着其后熟进程,ACC含量和乙烯释放量急剧增加,分别于采后第15天和第21天达到峰值,同时伴随出现呼吸跃变.采后果实的果心组织不仅对CO_2极为敏感,而且还对低氧敏感.两者导致组织伤害的症状相同,但集中表现的时间不同.CO_2伤害多出现在贮藏前期,而低氧伤害则主要在贮藏中、后期出现.鸭梨果实气调贮藏的适宜气体组分为7%~10%O_2和0%C0_2. 相似文献
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短裙竹荪多糖清除O^—.2及对人工细胞膜自由基氧化的影响 总被引:3,自引:0,他引:3
短裙竹荪「Dictyophora duplicata(Bose)Fisher」经热水抽提,乙醇沉淀,Sevag法去蛋白,乙醇分级分离,再经DEAE-纤维素柱层析得多糖组分PS。在体外产生O^-.2的反应体系中,竹荪多糖组分PS在较低浓度下(〈200mg/L)具有清除O^-.2的作用,而在较高浓度下(〉200mg/L)作用不明显。同时用荧光法研究了竹荪多糖组分PS对人红细胞膜脂质过氧化的影响,结果表 相似文献
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裂缝是大体积混凝土结构施工中的质量通病,如何有效控制是一个工程技术人员所普遍关注的技术难题。本文结合工程实践,介绍了大体积混凝土结构施工中最常见的温度裂缝产生的原因,提出了优化混凝土组分材料、控制混凝土温度、改善约束条件等有效控制措施。 相似文献
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氧化镧对Cu—O/γ—Al2O3催化剂活性和结构的影响 总被引:1,自引:0,他引:1
在色谱-微反流动法实验装置上考察了三种催化剂对CO和CH4的氧化活性,并运用BET、XRD及TPR等技术研究了La2O3的添加对Cu-O/γ-Al2O3催化剂性能及催化剂氧化还原特性的影响.结果表明,La2O3的添加不仅使La2O3与CuO之间产生相互作用,且也与载体γ-Al2O3产生相互作用;La2O3的添加促进了CuO在γ-Al2O3上的分散,并使CuO均以非晶相形式存在,从而改善了Cu-O/γ-Al2O3催化剂对CO和CH4的氧化活性,还使La-Cu-O/γ-Al2O3催化剂的TPR峰温降低了75℃. 相似文献
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分析了主从触发器的逻辑结构,提出了主从触发器由特征锁存器和通用锁存器构成的设计模式.基于这一模式,用限幅电压开关理论指导设计了nMOS三值D型、JKL型和T型主从触发器.结果表明,这一设计模式可克服JKL型和T型通过D型主从触发器转换得到的缺点,并且证明了限幅电压开关理论可在开关级指导触发器设计 相似文献
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超微LaMO3(M=Fe,Cr,Mn,Co)的导电性与粒度的关系 总被引:1,自引:0,他引:1
用Sol-Gel法合成了LaMO_3(M=Fe,Cr,Mn,Co)超微粉末.X射线衍射分析表明,不同焙烧温度下所合成的化合物均为单相.SEM分析表明,粒子呈球形,室温电阻率测量表明,电阻率随粒度的变化呈两种类型:LaFeO_3,LaCrO_3随粒度的增大,电阻率增加;而LaMnO_3,LaCoO_3随粒度的增大,电阻率减小. 相似文献
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用化学还原法制备了非晶态合金催化剂Ni-B、Co-B和Co-Ni-B.合金的非晶性质由X射线衍射(XRD)及透射电子显微镜(TEM)鉴定.组成用电感耦合等离子发射光谱(ICP)分析.在高真空程序升温脱附质谱(TPD-MS)装置上研究了CO、H2在三种催化剂上的吸附及CO和H2的表面反应(TPSR).发现CO和H2在三种催化剂上分别有二种和一种吸附态,吸附强度和二种吸附态的数目在不同合金上有较大差异.CO加氢反应的主要产物是CH4、CO2和H2O,其中CO在催化剂表面上的解离是反应的控制步骤. 相似文献
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为了制备抗环丙沙星单克隆抗体,首先采用碳二亚胺法合成了环丙沙星与载体蛋白偶联的免疫抗原和包被抗原,免疫BALB/c小鼠,取效价最高的小鼠脾细胞与骨髓瘤细胞SP2/0融合,HAT培养基筛选,有限稀释法克隆化,获得1株稳定分泌抗环丙沙星单克隆抗体的杂交瘤细胞株。检测结果显示,杂交瘤细胞染色体数目平均102条,培养上清的效价为1:1.28×10^3,单抗腹水效价达1:1.024×10^6,IC50为68.31ng/mL,属于IgM型,轻链kappa,CI—ELISA法显示单抗对环丙沙星有高度的选择性,提示获得的单抗可望用于环丙沙星残留物的免疫化学检测。 相似文献
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由于化疗、放疗、免疫抑制剂治疗、介入治疗的广泛开展及抗生素的广泛应用,恶性肿瘤继发肺部真菌感染呈上升趋势。肺部真菌感染的确诊有赖于真菌的培养和分离,而常用的咳痰标本又极易受到污染,很难确定其病原性。我们经纤维支气管镜(纤支镜)防污染毛刷(protectedspecimenbrush,PSB)对135例可疑肺部真菌感染患者采样进行真菌培养和涂片检查,其中56例恶性肿瘤继发的肺部感染患者中26例诊断为肺部真菌感染。现报告如下。1,资料与方法1.1,临床资料56例均为我院住院和门诊可疑肿瘤继发的肺部真菌感染患者,男31例,女25例,年龄47 ̄68岁,平均年龄6… 相似文献
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Sona Valsaraj K. T. Augusti Varghese Chemmanam Regi Jose 《Indian journal of clinical biochemistry : IJCB》2009,24(2):175-178
In the present study the efficacies of therapy with insulin, sulphonylurea or insulin + metformin on NIDDM patients are compared.
One group which was on a definite dose of insulin therapy, but with uncontrolled diabetes was treated by doubling the insulin
dose, a second group whose diabetes was not controlled by glibenclamide was switched over to another sulphonylurea viz; glimepiride
and a third group whose diabetes was not controlled by insulin therapy was switched over to a combination therapy with insulin
+metformin. After recording their initial blood parameters all the groups were treated as above for 3 months, and the parameters
were again determined. The fasting blood sugar and serum lipids of the first group were controlled significantly, but the
values were far above normal range. However HDL Cholesterol and atherogenic index were near normal range. In glimepiride treated
group, none of the parameters showed any amelioration. In the combined therapy group, control of blood sugar and atherogenic
index was more or less the same as for group 1, but hyperlipidemia remained slightly above that of the same. From the findings
we can infer that in long term diabetes treatment higher doses of insulin and combined therapy with insulin and metformin
may be more beneficial than with low doses of insulin or sulfonyl urea alone 相似文献
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S. K. Pandey S. Pandey R. M. Mishra M. Indurkar 《Indian journal of clinical biochemistry : IJCB》2017,32(1):103-105
Normal iron levels are required to prevent thrombocytosis by inhibiting thrombopoiesis. Thrombocytosis is usually associated with a mild iron deficiency and is the result of a lack of inhibition of thrombopoiesis. Study participants were 430 iron deficiency anemia (IDA) patients. Ten (10) mL of venous blood were collected for the subjects. Ferritin analysis was done by ELISA method while Hemogram analysis was done by auto-analyzer. Factor V Leiden, PRTG20210A, and MTHFR C677T genotype analysis was performed by PCR–RFLP method. Among the patients, 9 were heterozygous (G>A) and 2 were homozygous (A>A) carrier of FV Leiden; while 20 were heterozygous (C>T) and 3 were homozygous (T>T) for MTHFR polymorphism. None of the patient was identified with PT mutation. Patients with thrombosis gene marker had lower hemoglobin, mean corpuscular volume, mean corpuscular haemoglobin levels, and mean corpuscular hemoglobin concentration than patients without thrombosis gene marker. Serum ferritin was elevated in subject with the absence of thrombosis gene markers. Our data suggest a high impact of inherited hypercoagulability risk factors in the pathogenesis of IDA and its complications. 相似文献
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半导体激光治疗慢性牙髓炎和慢性根尖周炎 总被引:4,自引:0,他引:4
为探讨利用半导体激光治疗慢性牙髓炎和慢性根尖周炎的新办法,使用半导体激光光源及单模光纤将激光引入根管,对128只牙根管进行照射,并与常规根管治疗术进行对照比较,结果表明,激光治疗慢性牙髓炎和慢性根尖周炎组治愈率分别为96.15%和94.74%,疗效优于对照组,经统计学检查有显著性差异。 相似文献
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探讨了胰腺癌血管受累的CT分型与肿瘤手术可切除性的关系.对43例经手术、病理证实的胰腺癌进行薄层CT动态扫描,根据确定的CT标准,观察肿瘤与血管的关系,并与手术结果对照.发现胰腺癌血管受累以C型最常见,占37.2%,A型10例,肿瘤切除率100%(10/10),B型9例,切除率为77.8%(7/9),C型、D型24例,均不可切除.表明薄层CT动态扫描能提高胰腺癌血管受累的诊断正确率,血管受累CT分型对外科制定手术计划具有一定价值. 相似文献
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Maryam Farahnak Zarabi Ali Farhangi Samaneh Khademi Mazdeh Zahra Ansarian Davod Zare Mohammad Reza Mehrabi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(2):154-160
Carboxylate-modified gold nanoparticles (GNPs) were synthesized in a simple one-step process based on the reduction of tetrachloroauric acid by aspartic acid in water. GNPs were identified by UV–Vis spectroscopy, dynamic light scattering (DLS) and transmission electron microscopy. Conjugation of protein molecules with functionalized nanoparticles was performed through electrostatic interaction. The GNP–protein conjugates were characterized by gel electrophoresis. The interaction between functionalized GNPs and protein molecules lead to conformational transition of protein structure after conjugation of protein with GNPs. This process was investigated by fluorescence spectroscopy and circular dichroism spectroscopy. 相似文献
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以恶唑啉为导向基团 ,通过邻位锂化方便地高非对映选择性地合成了一系列平面手性二茂铁硫恶唑啉、硒恶唑啉和膦恶唑啉配体 .应用于 1 ,3 二苯基烯丙基醋酸酯的烯丙基烷基化反应 ,ee值最高可达 99%,膦氮配体在烯丙基胺化反应中 ,ee值最高也可达 97%.此外 ,发现中心手性起到了决定产物ee值和绝对构型的作用 ,平面手性和中心手性的匹配在取得高对映选择性上是重要的 .设计合成的一类平面手性二茂铁修饰的手性口袋型双膦配体 ,由于有平面手性的辅助而具有更有效的诱导效应 .这类配体在前手性亲核试剂的不对称烯丙基化生成季碳氨基酸衍生物构及alpha 位双取代季碳酮反应中 ,ee值最高分别可达到 75 %和 95 %.设计合成的 1 ,1’ 二茂铁膦氮配体 ,在单取代的烯丙基醋酸酯的钯催化区域选择性及对映选择性的烯丙基烷基化及胺化反应中 ,显示了非常高的反应活性、区域选择性和对映选择性 .配体中BINOL羟基由于和苄胺存在分子间氢键而对反应的选择性起到了关键作用 ,并从实验上给予了证明 相似文献