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31.
以易制备的2-(1,2-亚乙/1,3-亚丙二硫)亚甲基-3-羰基丁酸1为原料,经与氯化亚砜的氯化反应后,与胺反应成功地以较好产率(40.5%-72.0%)合成重要的有机合成中间体2-(1,2-亚乙/1,3一亚丙二硫)亚甲基-3-羰基-N-芳(烷)基丁酰胺3.  相似文献   
32.
以6-甲基-2-(α-羟甲基)-IH-苯并咪唑(MHMBM)作为荧光探针,利用蛋白质对MHMBM荧光增敏作用,建立了测定人血清总蛋白的新方法。结果表明,在中性水溶液中,MHMBM的荧光强度与牛蛋白(BSA)的浓度呈良好的线性关系,相关系数(r)为0.9995,检出限2.3μg/mL,线性范围4.6—60.0μg/mL。本方法用于测定两种样品溶液中的总蛋白,RSD(n=6)分别为1.7%和1.3%,回收率95.5%和98.6%。  相似文献   
33.
地方高校实验教学示范中心建设的研究与实践   总被引:10,自引:10,他引:10  
高等学校实验教学示范中心将引领我国高校实验室建设和实验教学改革的发展趋势,国家级实验教学示范中心建设被列为教育部本科教学质量工程之一,作为地方高校如何创建省级和国家级实验教学示范中心,文中提出了多出精品,创出特色的建设思路。  相似文献   
34.
对青少年运动员胫骨疲劳性骨膜炎的实验研究   总被引:2,自引:0,他引:2  
笔者针对青少年运动员中胫骨疲劳性骨膜炎发病率高的特点,自1999年以来,以来 往信函和个别访谈的方法,对河南、湖南、湖北、广东和广西五省35所高级中学、10所高等 院校体育系和8所体校的410例患者采用1/1000Hg2(NO3)2.2H2O(千分之一硝酸亚汞)进行 局部贴敷,并配合理疗、点穴按摩等方法,取得显著疗效,治愈率高达96%,深受青少年体 育爱好者的欢迎.  相似文献   
35.
Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) andHelicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status ofH. pylori was determined by histologic examination, RUT,14C-UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1 were significantly higher in patients withH. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml,P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection ofH. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml, respectively (P<0.05). The serum levels of sICAM-1, proved to be significantly correlated with the density ofH. pylori colonization in gastric mucosa (r s=0.316,P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls (P<0.05). Conclusions: These results indicated thatH. pylori infection up-regulates the expression of sICAM-1.  相似文献   
36.
37.
This article describes the inter‐relationship between school organization and classroom instructional style. Two distinct models of school organization, the bureaucratic and open‐systems models, are characterized in terms of three major dimensions of school life; a. the behavior of administrators, teachers and students, b. work design and tasks, and c. space‐time allocations. It is shown that the bureaucratic model of school organization parallels, and sustains, the traditional whole‐class method of teaching in all of the three dimensions. An open‐systems model of staff organization at the school level is required to sustain an alternative form of classroom instruction such as cooperative learning. The approach presented here emphasizes the inter‐relatedness of all three dimensions of schooling at the organizational and classroom levels. It also claims that the implementation of genuine instructional change, that entails new patterns of interpersonal relations in the classroom, is contingent upon similar changes being made at the level of the school as an organization. Lack of attention to school organizational change may explain why efforts at changing instruction at the classroom level frequently fail to yield results.  相似文献   
38.
Abstract

Purpose: Formal agricultural research has generated vast amount of knowledge and fundamental insights on land management, but their low adoption has been attributed to the use of public extension approach. This research aims to address whether and how full participation of farmers through the concept of Rural Resource Centre (RRC) provides new insights for the development of alternative and farmers-based extension methods.

Design/Methodology/Approach: Using the Concept of RRC, this research assesses the role of farmers in on-farm demonstrations and scaling-up of land management practices, and investigates effective ways to enhance beneficial interactions between researchers, extension workers and farmers in view of improving adoption.

Findings: The findings suggest that farmers can effectively participate in demonstrations and scaling-up of agricultural practices. This participation is enhanced by judicious incentives such as higher crop yields that motivate farmers and influence adoption. The current success of the approach stems from the fact that farmers, extension workers and researchers jointly implement the activities and their different aims were achieved simultaneously: scientific results for researchers, better agricultural practices for extension workers, and economic success and free choice for farmers.

Practical implications: This research concludes that farmers have the capacities to play an innermost role in demonstrations and scaling-up of agricultural practices. However, there is a need to build and strengthen their capacities to facilitate their participation and contribution.

Originality/Value: The article demonstrates the value of the preponderant role of farmers in on-farm demonstrations and scaling-up practices by exhibiting the beneficial interactions between researchers, extension workers and farmers.  相似文献   
39.
《Africa Education Review》2013,10(1):199-217
Abstract

Research has revealed that many of the historically disadvantaged schools in South Africa experience difficulty in implementing policies aimed at restoring the quality of teaching and learning. The difficulty has been attributed to several factors such as poor conceptualisation and implementation of quality management systems at school level. This article reports on empirical research that investigated the possibility of applying Total Quality Management principles in schools for the purpose of restoring the culture of learning and teaching. Data was collected through qualitative and quantitative methods in selected schools situated in the Tshwane North District. The findings revealed that there is a gap between what is provided in the policy framework on the management of quality teaching and learning. It is recommended that in order to fill the gap, schools need to apply customised principles of Total Quality Management. The primary aim of this research was to develop such an integrated framework that is not only theoretically sound but that has been customised for schools’ contexts and conditions.  相似文献   
40.
用READ及READKEY()函数模拟BROWSE全屏幕编辑格式,利用代码实现数据库录入数据的简化操作,从而提高录入速度。  相似文献   
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