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21.
张德礼 《中国科学B辑(英文版)》1991,(8)
In this paper, superhigh reproductive rate strains of MEV with titre more than HA8192* or TCID50 log9.7 10 have been achieved both by cultivation in cell lines with different susceptibility to MEV and by isolating and identifying in field by the author. The systematic tests proved that S18 and L12 strains of MEV are the best strains for vaccine preparation. In this study, the best means for the tissue cultivation of MEV and the most advanced technological process for the production and detection of serum-free cell-cultured MEV fluids with super-high HA titre in batches in large quantities have been established for the first time. Optimum conditions for MEV inactivation were determined, and safe and effective inactivated vaccines with mineral oil or A1(OH)3 gel adjuvant were successfully prepared with serum-free cell-cultured MEV fluids. Both vaccines with different adjuvants can be manufactured in batches in large quantities and have been widely used all over China since 1986. The change laws of the imm 相似文献
22.
Yoshizumi Ishikawa Hideyasu Honda Yoshiyuki Sugahara 《Journal of Sol-Gel Science and Technology》2000,19(1-3):365-369
The conversion of tetrakis(diethylamino)titanium (Ti(NEt2)4) into titania via either a combination of hydrolysis (Ti(NEt2)4 : THF : H2O = 1 : 10 : x, x = 2, 4, 10) at ambient conditions and calcination (method A) or hydrolysis in a water-tetrahydrofuran (THF) mixture (Ti(NEt2)4 : THF : H2O = 1 : 10 : 100) at reflux (method B) was investigated. Titanium tertiary butoxide (Ti(O
t
Bu)4) was also used as a substitute for Ti(NEt2)4. The hydrolysis via method A resulted in the formation of amorphous solids containing organics. Thermal analyses showed that the hydrolysis products showed mass losses up to 500°C probably due to the presence of diethylamine (Et2NH) formed via the hydrolysis of Ti(NEt2)4 in the hydrolysis products, while a mass loss of the hydrolysis product from Ti(O
t
Bu)4 was completed up to about 200°C. After calcination at 600°C, anatase or a mixture of anatase and rutile was obtained. The crystallization behavior of the hydrolysis products from Ti(NEt2)4 was different from that of the hydrolysis product from Ti(O
t
Bu)4. The hydrolysis via method B gave only an amorphous material from Ti(NEt2)4, while a crystalline titania (anatase and brookite) formed from Ti(O
t
Bu)4. 相似文献
23.
5-Hydroxytryptamino-induced calcium sparks in cultured rat stomach fundus smooth muscle cells 总被引:1,自引:0,他引:1
With the imaging fluorescence probe of Ca2+ (fluo-3) and a laser scanning confocal micro-scope, the spontaneous localized calcium release event was first discovered in resting rat cardiac myocytes by Cheng[1] in 1993. A mathematical simulation is developed with computer in order to reveal the effect, which is immediately suggested that these events are likely to reflect the local-ized release of Ca2+ from a small cluster of ryanodine-sensitive Ca2+ release channels in sar-coplasmic reticulum … 相似文献
24.
Hyungrak Kim 《Journal of solid state chemistry》2005,178(6):1935-1939
The compound Ca14MnP11 crystallizes in the Ca14AlSb11 structure type with the tetragonal space group I41/acd (Z=8) and lattice parameters of , c=20.7565(9) at 90 K. The structure consists of MnP49− tetrahedron, P37− trimer, 4 P3− isolated anions and 14 Ca2+ cations. Similar to other compounds of this structure type containing phosphorous, the P37− trimer has a central P atom that is best modeled in the structure as being equally split between two sites. In addition, there is no additional distortion of the manganese-containing tetrahedron compared with the main group analog, Ca14GaP11, suggesting that the Mn oxidation state is Mn2+. Temperature-dependent magnetic susceptibility shows that the compound is paramagnetic over the entire temperature range measured (2-300 K). The data can be fit with a modified Curie-Weiss law and provide an effective magnetic moment of 5.80 (2) B.M. with a Weiss constant of −2.13(2) K and . This moment is significantly higher than those measured for any of the Mn-containing analogs and is consistent with Mn2+. This result will be discussed in light of the electron counting scheme for Mn compounds of the Ca14AlSb11 structure-type. 相似文献
25.
Gopa KarAnil K. Saikia Upasana BoraSanjoy K. Dehury Mihir K. Chaudhuri 《Tetrahedron letters》2003,44(24):4503-4505
The bright yellow crystalline cetyltrimethylammonium tribromide (CTMATB) reagent has been synthesized from the reaction of CTMAB and KBr with H2MoO4·H2O, H2O2 and H2SO4 in the molar ratio 1:2:0.01:4:0.93. CTMATB selectively oxidizes a variety of dialkyl and alkyl aryl sulfides to the corresponding sulfoxides in high yields under mild conditions. 相似文献
26.
Angelica Sharapova Marina Olkhovich Svetlana Blokhina German L. Perlovich 《Molecules (Basel, Switzerland)》2022,27(19)
The important physicochemical properties of three novel bioactive hybrid compounds with different groups (-CH3, -F and -Cl) were studied, including kinetic and thermodynamic solubility in pharmaceutically relevant solvents (buffer solutions and 1-octanol) as well as partition coefficient in system 1-octanol/buffer pH 7.4. The aqueous solubility of these chemicals is poor and ranged from 0.67 × 10−4 to 1.98 × 10−3 mol·L−1. The compounds studied are more soluble in the buffer pH 2.0, simulating the gastrointestinal tract environment (by an order of magnitude) than in the buffer pH 7.4 modelling plasma of blood. The solubility in 1-octanol is significantly higher; that is because of the specific interactions of the compounds with the solvent. The prediction solubility behaviour of the hybrid compounds using Hansen’s three-parameter approach showed acceptable results. The experimental solubility of potential drugs was successfully correlated by means of two commonly known equations: modified Apelblat and van’t Hoff. The temperature dependencies of partition coefficients of new hybrids in the model system 1-octanol/buffer pH 7.4 as a surrogate lipophilicity were measured by the shake flask method. It was found that compounds demonstrated a lipophilic nature and have optimal values of partition coefficients for oral absorption. Bioactive assay manifested that prepared compounds showed antifungal activities equal to or greater than fluconazole. In addition, the thermodynamic aspects of dissolution and partition processes have been examined. Bioactive assay manifested that prepared compounds showed antifungal activities equal to or greater than the reference drug. 相似文献
27.
随着我国高等教育迈向深化改革的新发展阶段,传统工科教学也面临理论结合实践、基础结合创新、传统结合多元的改革新目标和新要求。本研究以理论力学课程教学为例,提出了一种以学生为主体的短视频创作在工科基础课程教学中的应用模式,有效提升了学生学习效率和知识掌握程度,对开拓学生学习能力和创新思维具有显著促进作用。该模式为工科多元教学提供了新的思路,对与时俱进优化工科教学改革具有重要参考价值。
相似文献28.
欧洲大型强子对撞机(LHC) 上发现的125 GeV新希格斯粒子可能成为标准模型预期的“上帝粒子”。这一革命性发现开启了探索宇宙中一切基本粒子质量起源的新时代,成为21世纪粒子物理学的转折点。文章着重介绍:(1) 探寻上帝粒子的重大科学意义;(2) 探索质量起源的历史,以及为什么牛顿力学和爱因斯坦相对论均未解决质量起源问题;(3) 神秘的真空与希格斯机制;(4) 上帝粒子是如何提出的和怎样在LHC上发现的;(5) 展望21世纪质量起源的探索与新物理定律的革命。 相似文献
29.
"一带一路"战略为深化我国与沿线国家的教育交流合作提供了重要契机,也为我国的新工科人才培养体系的理论研究与教育实践开拓了新视野,提出了新挑战。在以新技术、新业态、新模式、新产业为代表的新经济蓬勃发展的大背景下,对工程科技人才提出了更高要求。建设具有新理念、新结构、新体系、新质量、新模式的新工科,迫切需要借助国际化加快工程人才教育体系的改革创新。构建面向"一带一路"的工程教育国际化新体系,面向新工科人才培养,密切结合"一带一路"沿线各国工科人才培养的实际情况,以工程力学、航空航天工程、机械工程等专业的国际化联合培养为抓手,深入研究面向新工科建设的"一带一路"工程教育国际化新体系。 相似文献
30.
通过荧光法在不同温度下研究了3种第三代头孢新药: 盐酸头孢吡肟、头孢匹胺和头孢唑肟钠与人血清白蛋白(HSA)和牛血清白蛋白(BSA)的作用, 分别应用荧光淬灭和荧光加强理论公式计算了它们的结合常数等, 进而分别计算了它们的热力学函数. 因对应于不同的理论公式得出的KA值并不完全相同, 由此得到它们相应的热力学参数也有所不同. 本文对这些热力学数据的差异进行了分析比较, 结果表明: 基于荧光加强理论公式(4)获得的热力学数据显示更为合理. 因而我们建议, 即使在研究受体-底物的荧光淬灭反应时, 采用荧光加强理论公式(4)可以获得更符合实际的结果. 相似文献