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1.
Objective: To determine the effective nucleotide sites of ribozymes against HCV, and obtain a highly effective, nontoxic and
inexpensive antisense ribozyme specific for HCV. Methods: Two effective ribozymes, targeted to HCV 5’NC region and C region,
were designed and synthesized. Eukaryotic expression vectors, pSV2-gpt. CD-SR (, containing either HCRZNC or HCRZC were constructued
and transfected into MT-2 cells, which had been infected by HCV. Quantitative PCR and hydridization were used to determine
the effect of inhibition of HCV by ribozymes. Results: HCRZNC and HCRZC suppressed the replication of HCV by 54.7% and 62.1%,
respectively. Furthermore, when both ribozymes were cotransfected into cells, they suppressed replication by 78.8%. Conclusion:
Two specific antisense ribozymes have strong inhibitory effects on the replication of HCV in cultured cells, and have better
effect when used together. 相似文献
2.
3.
本首先分析了当前我国专科教育所面临的发展困境与成因,进而提出了改革我国专科教育体制、建立新型专科教育运行机制的构想与相关的政策性建议。作认为,作为高等教育的一个重要组成部分,专科教育为我国的社会主义教育事业作了重要贡献,但目前又进入到一个新的发展转型期,挑战与发展的机遇关存;改革计划管理的约束的体制,寻求办学效益和社会效益的统一,建立起与社会主义市场经济体制相适应的专科教育体制与机制,实现教育体制与学校功能的战略性调整,是现阶段专科教育改革发展的必然趋势和重要条件。 相似文献
4.
John U. Ogbu 《The Urban Review》1995,27(3):189-205
Culture has featured prominently in minority educational research, policies, and intervention since the early 1960s. It is
receiving even more attention today in minority education discourse due to the emergence of cultural diversity and multicultural
education as popular national issues. A careful analysis of the new discourse suggests, however, that the issue has shifted
from how cultural differences enhance or deter the school adjustment and academic performance of minority children to the
problem of cultural hegemony and representation in school curriculum and other domains of education. But cultural diversity
and multicultural education are only a partial solution to the problems of culture in minority education. This essay is in
two parts. In part one I argue for a reconsideration of the earlier question about how culture affects minority school adjustment
and academic performance. I also proposecultural frame of reference as a new level of analysis of the cultural problems that confront minority students at school. In part two I illustrate my
points with two case studies from Minority Education Project in Oakland, California. 相似文献
5.
6.
Faculty satisfaction is considered an important factor of quality in online courses. A study was conducted to identify and confirm factors affecting the satisfaction of online faculty at a small research university, and to develop and validate an instrument that can be used to measure perceived faculty satisfaction in the context of the online learning environment. The online faculty satisfaction survey (OFSS) was developed and administered to all instructors who had taught an online course in fall 2007 or spring 2008 at a small research university in the USA. One hundred and two individuals completed the web‐based questionnaire. Results confirm that three factors affect satisfaction of faculty in the online environment: student‐related, instructor‐related, and institution‐related factors. 相似文献
7.
G. M. Sankolli M. I. Khatkhatay M. P. Desai D. K. Pardhe P. C. Ishrad U. M. Joshi 《Indian journal of clinical biochemistry : IJCB》1992,7(1):71-74
Aprototype kit for the detection of occurrence of ovulation based on urinary pregnanediol glucuronide estimations by ELISA
was developed in our laboratory. This kit was sent for evaluation at 4 centres in Bombay and Pune, India. The diagnosis of
ovulation/anovulation based on the results of the kit is comparable with that based on reference parameters commonly used
(ultrasonography of ovarian follicles and serum progesterone estimations). The accuracy of the test was 93.5%, specificity
was 87.5% and sensitivity was 95.7%. This rapid indigenous test can be very useful in assessing ovulatory status of the woman
by the clinicians in their offices. 相似文献
8.
Foundational issues in evolution education 总被引:1,自引:0,他引:1
There is a great need for effective evolution education. This paper reviews some of the evidence that demonstrates that need and analyzes some of the foundational semantic, epistemological, and philosophical issues involved. This analysis is used to provide a functional understanding of the distinction between science and non-science. Special emphasis is placed the scientific meaning of the terms theory, hypothesis, fact, proof, evidence, and truth, focusing on the difference between religious belief and acceptance of a scientific theory. Science is viewed as theologically neutral and as not mutually exclusive from religion. Finally, a number of practical recommendations to the classroom biology teacher are presented. 相似文献
9.
Ajay Kumar D. H. Shah M. G. R. Rajan U. R. Thakare S. M. Sharma 《Indian journal of clinical biochemistry : IJCB》1992,7(2):159-164
An external quality assessment was conducted to assess the performance of various laboratories for RIA of thhyroid related
hormones in two phases. In the first phase thirty five laboratories participated. At the end of first phase a meeting cum
workshop was organised to discuss the results of first phase, difficultires faced by the participants and pinpoint the short
oming. A second phase was then initiated with an objective of improvement in the performance, if any, where twelve samples
from four pools were distributed to twenty four laboratories who participated for the second phase. The overall return of
the results increased significantly from 71.8% (1586/2208) for the first phase to 92.4% (732/792) for the second phase. The
inter laboratory %CV for T3, T4 and TSH were lower during the second phase (30.6%, 19.0% and 31.6% respectively) as compared to those observed during first
phase (36.3%, 22.7% and 52.8% respectively). Similarly, there was an improvement in reproducibility of ALTM as %CV for T3, T4 and TSH decreased from 6.0%, 9.8% and 13.4% respectively to 4.5%, 4.6% and 8.5% respectively. The individual performances
of the participating laboratories viz. bias, variability of bias and imprecision also showed a trend towards improvement as
percent laboratories having desirable or acceptable results for T3, T4 and TSH increased from 10.7%, 60.7% and 0.0% respectively to 20.8%, 66.7% and 22.2% respectively. External quality assessment
thus appears to be beneficial in assessing the performane of a laboratory in comfparison with other laboratories and indeed
helps in improving the performance. 相似文献
10.
Tunable pores (TPs) have been used for resistive pulse sensing of 1 μm superparamagnetic beads, both dispersed and within a magnetic field. Upon application of this field, magnetic supraparticle structures (SPSs) were observed. Onset of aggregation was most effectively indicated by an increase in the mean event magnitude, with data collected using an automated thresholding method. Simulations enabled discrimination between resistive pulses caused by dimers and individual particles. Distinct but time-correlated peaks were often observed, suggesting that SPSs became separated in pressure-driven flow focused at the pore constriction. The distinct properties of magnetophoretic and pressure-driven transport mechanisms can explain variations in the event rate when particles move through an asymmetric pore in either direction, with or without a magnetic field applied. Use of TPs for resistive pulse sensing holds potential for efficient, versatile analysis and measurement of nano- and microparticles, while magnetic beads and particle aggregation play important roles in many prospective biosensing applications. 相似文献