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101.
小鼠给予汉康液2.0g/kg/日,连续灌胃22天,结果表明该液能明显降低小鼠血清中丙二醛(MDA)含量,并对血清超氧化物歧化酶(SOD)活性有显著增强作用。  相似文献   
102.
华威大学是一所在短时间内迅速崛起的新大学,它的成功与其教学质量内部保障体系关系密切.本文在对华威大学教学质量保障体系的目标、组织构架、保障方法等进行分析的基础上,总结出其教学质量保障体系的几个突出特点:切合实际的质量目标、高效的组织结构、紧紧围绕"课程"保障教学质量的方法,并将这种突出强调"课程"要素的质量保障体系归纳为"课程型"质量保障模式.  相似文献   
103.
以质粒pSC101为载体,用鸟枪法将短小芽孢杆菌A3染色体的β—内酰胺酶基因,克隆至大肠杆菌HB101。经质粒检测及酶切电泳分析证明,克隆的β—内酰胺酶基因位于2.6kb的EcoRI片段上,将此片段连接到质粒PAL32转化枯草杆菌,亦能表达并向胞外分泌β—内酰胺酶。  相似文献   
104.
Objective: To construct a PC12 cell strain with neuronal differentiation, and observe the apoptosis and pro-liferation activity effects induced these cells by Amyloid beta-Protein (Aβ-43). Methods: 1) PC12 cells in logarithmicgrowth phase were subcultured for 24 h. After the culture fluid was changed, the cells were treated with Rat-β-NGF andcultured for 9 days. 2) Neuronal differentiation of PC12 cells in logarithmic growth phase were divided into four groups:control group (0), experimental group (1), experimental group (2) and experimental group (3). The concentrations of Aβ inthe four groups were 0 μmol/L, 1.25 μ mol/L, 2.5 μ mol/L and 5 μmol/L, respectively. The cells were harvested at 24, 48 and72 h later and stained with AnnexinV-FITC/PI after centrifugation and washing. Then flow cytometry was conducted toexamine the apoptosis percentage. 3) NGF-induced PC12 cells were selected and Aβ with different concentrations wasadded. The final concentrations of Aβ were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μ mol/L, respectively. After the cellswere incubated in an atmosphere of 5% CO2 at 37 ℃ in an incubator for 72 h, the OD values were examined. Results: 1)Neuronal differentiated PC 12 cell lines were successfully established. 2) Flow cytometric examination indicated that Aβ(1.25, 2.5, and 5.0 μmol/L) could effectively induce apoptosis of neuronal-differented cells at the 24 h, 48 h and 72 h timepoints. 3) Aβ (0-5.00 μ mol/L) had no obvious effect on proliferation or restraining of the neuronal differentiation of thePC 12 cells after a 72 h interacting process. Conclusion: This investigation revealed successful neuronal differentiation of thePC12 cell strain. The induction of apoptosis of the neurocytes by various concentrations of Aβ was observed and the in-fluence of Aβ on induced proliferation of PC 12 cells by Rat-β-NGF was revealed. This study -05 provide basis for futureresearch on the molecular cure of AD and interdiction of AD evolution.  相似文献   
105.
Objective: McKeown esophagectomy followed by cervical and abdominal procedures has been commonly used for invasive esophageal carcinoma. This minimally-invasive operative procedure in the lateral prone position has been considered to be the most appropriate method. We describe our experiences in minimally invasive McKeown esophagectomy (MIME) for esophageal cancer. Methods: Between March 2016 and February 2018, a total of 82 patients underwent MIME by a single group in our department (a single center). All procedure, operation, oncology, and complication data were reviewed. Results: All MIME procedures were completed successfully, with no conversions to open surgery. The median operative time was 260 min, and median blood loss was 100 ml. The average number of total harvested lymph nodes was 20.1 in the chest and 13.5 in the abdomen. There were no deaths within 30 postoperative days. Twenty cases (24.4%) developed postoperative complications, including anastomotic leak in 4 (4.9%), single lateral recurrent nerve palsy in 4 (4.9%), bilateral recurrent nerve palsy in 1 (1.2%), pulmonary problems in 3 (3.7%), chyle leak in 1 (1.2%), and other complications in 7 (including pleural effusions in 4, incomplete ileus in 2, and neck incision infection in 1; 8.54%). Average postoperative hospitalization time was 12 d. Blood loss, operation time, morbidity rate, and the number of harvested lymph nodes were analyzed by evaluating learning curves in different periods. Significant differences were found in operative time (P=0.006), postoperative hospitalization days (P=0.015), total harvested lymph nodes (P=0.003), harvested thoracic lymph nodes (P=0.006), and harvested abdominal lymph nodes (P=0.022) among different periods. Conclusions: Surgical outcomes following MIME for esophageal cancer are safe and acceptable. The MIME procedure for stages I and II could be performed proficiently and reached an experience plateau after approximately 25 cases.  相似文献   
106.
开放、多元、综合的艺术教育——美国艺术教育考察报告   总被引:5,自引:0,他引:5  
本文通过对美国艺术教育的实地考察和分析 ,指出美国艺术教育是在人文科技视野下实施的开放、多元、综合的艺术教育 ,具有如下几个特点 :从教育内容看 ,是跨学科、多层面、综合的 ;从教学方法看 ,是探究性和多元化的 ;从教育途径看 ,是学校、社会和家庭积极合作、互动的 ;艺术教师队伍结构灵活、专兼并举、素质较高。作者还就改革和加强我国艺术教育提出了若干思考  相似文献   
107.
尽管权益结合法存在许多缺陷,但由于购买法目前在我国尚不具备现实运用环境,且为了促进我国企业合并的发展,现阶段应允许我国进行换股合并的食业采采权豁结合法。  相似文献   
108.
构建现代教育服务体系的理论与实践   总被引:1,自引:0,他引:1  
大连教育学院为了很好地服务于本市新时期的初、中等教育,坚持科学发展观,积极构建现代教育服务体系:以"原野行动"服务于新农村建设的教师培训;以"大篷车计划"构建服务于教师专业发展的网络平台;以"空中课堂"服务于农村小学的英语教学;以"村小校长培训"服务于推进区域教育均衡发展的校长培训末梢工程;以"名师名校长培训"服务于全面实施素质教育的校长、教师培训;以"二二三四"工作服务于大连市的初、中等教育与教学。  相似文献   
109.
本文以2015年高职高专全国大学英语竞赛测试真题为例,对试题的结构、考察内容、测试题型、题量、分值比例进行归类量化分析,发现该竞赛试题的题量与难度呈逐年上升的趋势,测试内容愈加广泛,题型多样化的特点愈加明显;从而探讨该竞赛的测试特点与发展趋势,充分发挥大学英语竞赛对英语教学实践的促进作用。  相似文献   
110.
介绍了作研发的一套英语语音测试系统软件,能利用计算机判断识别学生的语言,可代替教师进行英语语音测试的繁重工作。  相似文献   
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