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991.
M. V. R. Reddy R. Alli B. C. Harinath 《Indian journal of clinical biochemistry : IJCB》2000,15(1):127-135
Lymphatic filariasis caused mainly by infection fromWuchereria bancrofti andBrugia malayi remains as the major cause of clinical morbidity in tropical and subtropical countries. Development of vaccine against filarial infection can act as additional measure to the existing therapeutic and vector control methods in the control of this disease. The main hurdles in the development of anti-filarial vaccine are the strict primate specificity ofWuchereria bancrofti, the paucity of parasite material, the diversity of clinical manifestations and their associated complex immune responses, lack of clear understanding on host-parasite interactions and the mechanisms involved in protective immunity. However in the past few years, the information generated in immuno-epidemiological studies, correlated with observations in experimental animals suggests that a filarial vaccine is feasible. Initially live irradiated infective larvae have been successfully used to induce high level of protective immunity in several animal models. Applying diverse strategies, variety of purified or recombinant filarial antigens have been explored for their ability to induce protection in different host-parasite systems. Some of these targeted filarial antigens induced high level of resistance in experimental animals against challenge infections. More focussed studies on thorough characterization of parasitological and immunological changes associated with resistance induced by such candidate protective antigens and on delivery mechanisms and safety aspects will be crucial in their selection for possible use in humans. 相似文献
992.
RobertC.Gallo LucMontagnier 《中国科技信息》2002,(24):41-42
超过7000万人感染HIV、2000万人死亡,艾滋病是医学史上最严重的流行病之一. 相似文献
993.
994.
Isis at seventy-five 总被引:1,自引:0,他引:1
995.
Harleen Mangat Tajamul Hussain C Sundaram MP JS Anandaraj 《Indian journal of clinical biochemistry : IJCB》2002,17(2):74-79
Poly A RNA status and itsin vitro translation in a rabbit reticulolysate cell free system, were assessed in the skeletal muscle of young boys with Duchenne
muscular dystrophy. Compared to normals there is a significant 48% increase in poly A RNA content of dystrophic muscle and
its translatability was increased by 56% based on35S methionine incorporation into total protein systhesised. Immunoprecipitation of the translated products with monospecific
antibodies showed that there is a 2.6 fold and a 2 fold increase in m and μ calpains respectively. This underlines the importance
of both synthetic and degenerative activities in the early pathology in DMD muscle. 相似文献
996.
In previous work it was established that the U.K. tractor industry was characterised by a high degree of technical change and that this was brought about by a process of more or less continuous incremental innovation. What was lacking was an analysis of how much technical change had been introduced and an indication of the role played by technical change in determining the performance of the U.K. tractor industry internationally. This paper concludes that on the average technical change in the industry had increased by as much as 150 percent during the years 1959–1977, though there is some indication that the rate of change might now be slowing somewhat.In order to determine the relative importance of technical change a method was developed to operationalise the distinction between price and non-price competition as well as the idea of intrinsic (technical) and associative (non-technical) factors as constituents of the latter. Based on cross-sectional data for the year 1978, it has been possible to show that British manufacturers tend to produce moderately priced tractors of low to medium technical sophistication: that German manufacturers produced the most technically sophisticated tractors; that the Italian manufacturers are not generally more sophisticated, technically, than the British producers except with respect to their development of four-wheel drive; and that COMECON-based producers combine a very low price with some degree of technical sophistication. Finally, it has been possible to show that the tractors with the highest sales are among the less sophisticated in each of the power ranges investigated and that new entrants used technical sophistication as an element of their entry strategy. The answer to the question of what allows the market leader to be market leader required the development of measures for associative non-price factors, such as the availability of a dealer network brand loyalty, resale prices of tractor models, etc. By performing a regression analysis on these measures along with previously derived measures of quality-adjusted price and relative technical sophistication it has been possible to show that market leadership is achieved as a result of a balance of a number of factors, the most important of which are the size of the dealer network, warrants cost, advertising, technical sophistication and price. 相似文献
997.
A diverse sample of doctoral students completed an on-line questionnaire assessing their supervisors' academic, personal and autonomy support and their research self-efficacy. The more task-related help and personal support students received, the more positively they evaluated their supervision. The degree to which supervisors encouraged students to think and act autonomously (autonomy support) was not uniquely associated with students' supervision satisfaction but predicted greater research self-efficacy. A combination of high levels of autonomy and academic support was associated with the highest levels of research self-efficacy, whereas when greater levels of personal support were accompanied by low levels of autonomy support, students reported lower research self-efficacy. These results indicate that effective doctoral supervision involves supporting students to voice and act on their own ideas while simultaneously providing guidance on how to complete research tasks. 相似文献
998.
In this paper, we consider the difficulties that a group of internationally educated female teachers (female IETs) encountered in the process of seeking certification in the Canadian Maritimes. We read their experiences in the context of neoliberalism, in particular how they are positioned in the labour force and also the teaching profession. We consider the material effects of differences such as gender, race, ethnicity, and regional location for the female IETs. Further, we underscore implications for teacher education. 相似文献
999.
Effective teachers are often creative ones, yet an examination of creative teaching is largely invisible in the North American creativity literature. Even within education there is little about teachers’ own creative practice. Nonetheless, there are benefits to studying creative teachers: in education it can explicate ways of enhancing teachers’ creativity and enriching praxis; and in psychology it can extend our understanding of social and interpersonal creativity, as well as everyday creativity. This paper reviews 12 Canadian case studies of creative teaching conducted by a creative teaching research group. An in-depth elaboration of two themes, creative person and community, is presented. 相似文献
1000.
Not all young children benefit from book exposure in preschool age. It is claimed that the ability to hold information in
mind (short-term memory), to ignore distraction (inhibition), and to focus attention and stay focused (sustained attention) may have a moderating effect on children’s reactions to the home literacy environment. In a group of 228 junior kindergarten
children with a native Dutch background, with a mean age of 54.29 months (SD = 2.12 months), we explored therefore the relationship
between book exposure, cognitive control and early literacy skills. Parents filled in a HLE questionnaire (book sharing frequency
and an author recognition checklist as indicator of parental leisure reading habits), and children completed several tests
in individual sessions with the researcher (a book-cover recognition test, PPVT, letter knowledge test, the subtests categories
and patterns of the SON, and cognitive control measures namely digit span of the KABC, a peg tapping task and sustained attention
of the ANT). Main findings were: (1) Children’s storybook knowledge mediated the relationship between home literacy environment
and literacy skills. (2) Both vocabulary and letter knowledge were predicted by book exposure. (3) Short-term memory predicted
vocabulary over and above book exposure. (4) None of the cognitive control mechanisms moderated the beneficial effects of
book exposure. 相似文献