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Using ethnographic data collected in a second grade classroom over the course of a school year, this paper describes the ways in which one school's discourse of liberalism is deleteriously deployed. We view the school's discipline creed as emblematic of the school's liberal curriculum, and interrogate the effects on four African American boys in the classroom when the school enacts this creed. Despite the agency that these boys obviously had, they were unable to control the ways in which they were placed at a structural disadvantage and manipulated by a system far more powerful than they were. The results were that these four boys suffered. Not only did the intended liberal curriculum fail to be translated fully into the enacted curriculum, the liberal underpinnings of this curriculum precluded teachers and students from taking any critical stance. 相似文献
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Excised cotyledons of Pinus radiata D. Don cultured under shoot-forming(plus benzyladenine) and non shoot-forming (minus benzyladenine)conditions for 10 and 21 days were fed U-[14C]-glucose for 3h in the light followed by a 3 h chase period. The labellingof individual metabolites as well as 14C incorporation intoprotein was assessed. It was found that the general metabolicpatterns were qualitatively the same in shoot-forming and nonshoot-forming conditions, however, metabolism leading to respirationas well as to the synthesis of some amino acids and proteinsynthesis was enhanced in the shoot-forming cultures. (Received February 16, 1987; Accepted July 8, 1987) 相似文献
4.
The influence of rad2 mutation blocking incision of pyrimidine dimers on frequency of UV-light and 6-hydroxylaminopurine (6-GAP)-induced adenine-independent revertants was studied in the strains of Saccharomyces cerevisiae containing the same mutant allele of gene ADE2 in episomic plasmid and in chromosome. It was shown that the strains carrying the ade2 mutation in chromosome and in plasmid did not differ in sensitivity to lethal action of UV-light and 6-GAP. However, in the plasmid rad2 strain reversions were induced by UV-light more frequently (approximately 100 times), as compared to the chromosome strain. We observed no significant differences between reversion frequencies in plasmid and chromosome RAD strains. The tendency to enhanced 6-GAP-induced mutagenesis, less sharply expressed, was observed in the chromosome rad2 strain, as compared to the plasmid one. However, the plasmid RAD strain was characteristic of higher reversion frequency induced by 6-GAP, as compared to the chromosome strain. The possible mechanisms of these phenomena are discussed. 相似文献
5.
Richard W. Joy IV Kamlesh R. Patel Trevor A. Thorpe 《Plant Cell, Tissue and Organ Culture》1988,13(3):219-228
The effect of ascorbic acid on growth and shoot formation in callus cultures of tobacco (Nicotiana tabacum L.) was investigated, using young (4–12 subcultures) and old (more than 30 subcultures) tissue. It was found that ascorbate, at levels of 4–8×10-4M, enhanced shoot formation in both young and old callus. Treatment with ascorbate also speeded up the shoot-forming process. In addition, ascorbate completely reversed the inhibition of shoot formation by gibberellic acid in young callus, but was less effective in old callus. 相似文献
6.
Augmentin is a new combination manufactured by Smith Kline Beecham (Great Britain). It is composed of amoxycillin and clavulanic acid and has antibacterial activity. Augmentin was used in clinical trials in the therapy of 50 adult patients with suppurations after surgical operations on the organs of the abdominal cavity, general staphylococcal infections, pneumonia and prophylactically during the preoperative period. It was also used in the treatment of 30 children patients with bronchopulmonary affections and inflammatory otorhinolaryngological diseases. The clinical trials were performed in the Clinic of Infectious Diseases of the N. G. Gabrichevski? Moscow Research Institute of Epidemiology and Microbiology. For comparison ampicillin was used in the trials. Augmentin was shown to be an efficient formulation with antibacterial activity which could be successfully used in the parenteral therapy of severe affections due to organisms sensitive to it. In the treatment of the children patients with pneumonia augmentin by its therapeutic efficacy proved to be superior to ampicillin. The tolerance of augmentin was good. 相似文献
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TRANSFORMATION of allogenic lymphocytes in mixed cultures depends chiefly on an incompatibility between the lymphocyte donors at the major histocompatibility locus in man (HL-A), mouse (H-2) and rat (H-l)1. Although the mouse H-2 locus can be divided into several regions each of which controls one or more antigenic specificities2 and two or more subloci control HL-A antigens in man3, it is not known whether all parts of the major histocompatibility locus are equally important in eliciting transformation in mixed lymphocyte cultures. We now show that capacity to elicit lymphocyte transformation is different for different parts of the mouse H-2 locus. 相似文献
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