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51.
Objective: To investigate the effect of interleukin-18 (IL-18) on immune response induced by plasmid encoding hepatitis B virus middle protein antigen and to explore new strategies for prophylactic and therapeutic HBV DNA vaccines. Methods: BALB/c mice were immunized with pCMV-M alone or co-immunized with pcDNA3-18 and pCMV-M and then their sera were collected for analysing anti-HBsAg antibody by ELISA; splenocytes were isolated for detecting specific CTL response and cytokine assay in vitro. Results: The anti-HBs antibody level of mice co-immunized with pcDNA3-18 and pCMV-M was slightly higher than that of mice immunized with pCMV-M alone, but there was not significantly different (P>0.05). Compared with mice injected with pCMV-M, the specific CTL cytotoxity activity of mice immunized with pcDNA3-18 and pCMV-M was significantly enhanced (P<0.05) and the level of IFN-γ in supernatant of splenocytes cultured with HBsAg in vitro was significantly elevated (P<0.05) while the level of IL-4 had no significant difference (P>0.05). Conclusion: The plasmid encoding IL-18 together with HBV M gene DNA vaccines may enhance specific TH1 cells and CTL cellular immune response induced in mice, so that IL-18 is a promising immune adjuvant.  相似文献   
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Summary The paper focuses upon curriculum planning in the scientific disciplines at university level, although it is claimed the argument may be of wider applicability. Drawing upon the writings of philosophers of education from several decades ago (notably Schwab and Scheffler) whose work is too often overlooked in contemporary debates about the curriculum, and using illustrative examples from the author’s own experience, it is argued that too often the focus of science curriculum planning is the “rhetoric of conclusions” or the “substantive structure” — the current state of knowledge at the forefront of the respective disciplines — to the neglect of what Schwab called the “syntactical structure” of the sciences (which roughly approximates their epistemology). This aspect of these disciplines is essential for the general student trying to become familiar with the nature of science as a broad field of knowledge, for prospective teachers, and — contra Scheffler’s view — for students who aim at careers as researchers.
Zusammenfassung Der Beitrag der Epistemologie zur Curriuculumkonstruktion in den Naturwissenschaften Der Aufsatz fokussiert auf die Curriculumplanung für den naturwissenschaftlichen Unterricht in der universit?ren Lehrerausbildung, wenngleich behauptet wird, dass dieses Argument weitreichendere Anwendbarkeit besitzt. Der Text knüpft an erziehungswissenschaftlichen Schriften (insbesondere von Schwab und Scheffler) an, deren Ver?ffentlichung zwar einige Dekaden zurückliegt, deren Beitrag in den aktuellen Debatten aber oft übersehen wird. Darüber hinaus werden einige illustrative Beispiele aus dem Erfahrungsschatz des Autors genutzt, um zu zeigen, dass der Fokus der Curriculumplanung für die Naturwissenschaften — dem augenblicklichen Wissensstand der zu berücksichtigenden Disziplinen zufolge — zu oft in einer „Rhetorik der Schlussfolgerung“ oder „substantivischen Struktur“ besteht, was dazu führt, dass das, was Schwab die „syntaktische Struktur“ der Naturwissenschaften nennt (und ihrer Epistemologie ziemlich nahe kommt), vernachl?ssigt wird. Dieser Aspekt jener Disziplinen ist besonders wichtig für Studierende, die allgemeinbildend vertraut werden m?chten mit den Naturwissenschaften, für angehende Lehrer und — entgegen Schefflers Ansicht — für Studenten, die eine Karriere als Forscher anstreben.


“When walking in quicksand country, carry a stout pole — it will help you get out should you need to. As soon as you start to sink, lay the pole on the surface of the quicksand. Flop onto your back on top of the pole. Work the pole to a new position: under your hips and at right angles to your spine. Take the shortest route to firmer ground, moving slowly.” Piven/Borgenicht 1999, p. 18

This paper was presented at the conference Silence Between the Disciplines, Berlin-Brandenburg Academy of Sciences, Berlin, October 2002.  相似文献   
53.
Theories of adolescent connectedness suggest that adolescents strive to become connected by engaging with and valuing the people, activities, and worlds in their social ecology. The purpose of this study was to examine the psychometric properties of a measure designed to assess these worlds of connectedness among 320 junior high school students in Taiwan. The subscales and composite scales evidenced satisfactory reliability and concurrent validity. A hypothesized three-factor, higher order structural model of connectedness was cross-validated. Girls were generally more connected than boys. Both connectedness to school and to friends explained more variance in connectedness to self than did family connectedness. There was mixed support for separation-individuation processes. The measure appears promising in terms of future research on adolescent social development in the Asia Pacific.  相似文献   
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反应级数的确定在化学动力学研究中非常重要,现给出了利用计算机和用微分法确定反应级数的方法.为了使编程的程序简短、高效,采用MATLAB语言作为编程语言.  相似文献   
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In 2001, for the first time in the history of the International Association for Counselling, International Conference was held in a developing Asian country–India, with the theme Families in Transition–Counselling in Transition–Meeting the Challenges Ahead. This special issue contains some of the presentations made by Indian participants during this conference which best reflect the challenges and diversities of counseling efforts with families in India. The first article was specially written for this issue in order to give an international relationship of this journal an in depth contextual understanding of Indian families in transition and the challenges they pose to the contemporary Indian counselor. Two articles are reflected to counseling families affected by socio-politial and economic changes. Five authors have written on counseling related to physical and mental disability/addiction and last two articles are reflected to authors experiences as family counselors.  相似文献   
59.
Kinetic knowledge is of great importance in achieving good control of the pyrolysis and gasification process and optimising system design. An overall kinetic pyrolysis scheme is therefore addressed here. The kinetic modelling incorporates the following basic steps: the degradation of the virgin biomass materials into primary products (tar, gas and semi-char), the decomposition of primary tar into secondary products and the continuous interaction between primary gas and char. The last step is disregarded completely by models in the literature. Analysis and comparison of predicted results from different kinetic schemes and experimental data on our fixed bed pyrolyser yielded very positive evidence to support our kinetic scheme. Project (No. 2001CB409600) Supported by the National Key Basic Research Program (973) of China  相似文献   
60.
普通话二字组词语不同的声调组合方式 ,使前后位声调产生不同的动态变化形式。前位声调的动态变化明显表现在上声调变为低降调和中升调上 ;后位声调的动态变化则表现在调值的明显改变上。后位声调的动态变化更为普遍 ,应该引起足够的重视  相似文献   
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