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本对新疆南、北疆、东疆地区和乌鲁木齐市的101所民族中学进行实地的调查研究,通过对各民族中学体育教学中大纲、教材、场地器材、汉语授课、男女生分班情况、教师培训、教学计划以及对课程改革的认识等方面的分析.进一步了解新疆各地区民族中学学校体育状况,特别是“体育与健康”课程实施后,各地区民族中学学校体育教学现状以及所面临的问题,旨在加快新疆少数民族中学的体育教学改革和《体育与健康》课程教学研究。为新疆教育主管部门制定实施“体育与健康”课程教学提供决策依据。  相似文献   
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Beta 2-microglobulin (beta 2-m) is a highly conserved polypeptide (12,000 molecular weight; 12K) noncovalently associated with the heavy chain (45-48K) of the major histocompatibility complex (MHC) class I antigens. Its synthesis is required for expression of the HLA-A/B and H-2K/D heavy chains at the cell surface; beta 2-m is also associated with the human cell-surface antigens T6 and M241 isolated from thymocytes. However, on the T leukaemic cell line MOLT-4 some of the T6 antigens contain a different 12K subunit, termed beta t (refs 3, 7, 8). Purified human beta 2-m can exchange partially both with human beta 2-m associated with HLA-antigens, and with mouse beta 2-m associated with murine alloantigens. As MOLT-4 cells were grown in the presence of fetal calf serum (FCS) and as serum is known to contain some free beta 2-m, we examined whether beta t was bovine beta 2-m which had replaced endogenous beta 2-m on the surface of the cell. Here we show both that beta 2-m from FCS or human serum (HuS) used in cell culture can exchange with beta 2-m on the cell surface, and that beta t is in fact bovine beta 2-m.  相似文献   
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Summary To investigate heavy metal uptake in the common mushroomAgaricus bisporus, commercial cultures of the fungus were exposed to different amounts of copper ad cadmium. In contrast to copper, cadmium already exerted pronounced toxic effects at low concentrations (>10 M) in the compost and concomitantly enhanced the uptake of copper. Tyrosinase activity measured in the fruit bodies increased sharply, when small amounts of Cd (10 M) were added to copper-rich compost. Gel filtration experiments with crude extracts from fruit bodies demonstrated the absence of a low molecular weight metal binding protein.Acknowledgments. This work was supported by the Schweizerischer Nationalfonds grant 3.420–0.78 (to K.L.) and by Hauser Champignonkulturen AG. We are indepted to Dr D. Rast for helpful discussions.  相似文献   
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Zusammenfassung Die Gewebskonzentrationen an ATP, ADP, ATP+ADP, Kreatinphosphat, Kreatin und Kreatinphosphat + Kreatin sind unter vergleichbaren Bedingungen im linken Ventrikel von Mini-pig-Herzen kleiner als im Hundeherzen. Die Unterschiede in den Koeffizienten (ATP/ADP und Kreatinphosphat/Kreatin) dürfen narkosebedingt sein. Sämtliche Messgrössen sind nicht mit dem Entnahmeort der Biopsien (apikal, basal) korreliert.

Supported by the Swiss National Science Foundation (Grant Nr. 3.484).  相似文献   
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Summary We have briefly described an apparatus which permits us to register quantitatively different substances labelled with radioactive isotopes, formerly separated by paper chromatography. We were able to show by the Krebs' method, thus simplified, that the oxidative resynthesis of ATP is diminished in the hepatic homogenates of rats during a beri-beri crisis.  相似文献   
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The role of kinesin, dynein and microtubules in pancreatic secretion   总被引:1,自引:1,他引:0  
The regulated secretion of pancreatic zymogens depends on a functional cytoskeleton and intracellular vesicle transport. To study the dynamics of tubulin and its motor proteins dynein and kinesin during secretion in pancreatic acinar cells, we infused rats with 0.1 μg/kg/h caerulein. Electron and fluorescence microscopy detected neither dynein nor kinesin at the apical secretory pole, nor on the surface of mature zymogen granules. After 30 min of secretagogue stimulation, kinesin and the Golgi marker protein 58 K were reallocated towards the apical plasma membrane and association of kinesin with tubulin was enhanced. Disruption of acinar cell microtubules had no effect on initial caerulein-induced amylase release but completely blocked secretion during a second stimulus. Our results suggest that mature zymogen granule exocytosis is independent of intact microtubules, kinesin and dynein. However, microtubule-dependent mechanisms seem to be important for the replenishment of secretory vesicles by redistribution of Golgi elements towards the apical cell pole. J. Schnekenburger and I.-A. Weber have contributed equally to this work.  相似文献   
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Intellectual ability and cortical development in children and adolescents   总被引:1,自引:0,他引:1  
Children who are adept at any one of the three academic 'R's (reading, writing and arithmetic) tend to be good at the others, and grow into adults who are similarly skilled at diverse intellectually demanding activities. Determining the neuroanatomical correlates of this relatively stable individual trait of general intelligence has proved difficult, particularly in the rapidly developing brains of children and adolescents. Here we demonstrate that the trajectory of change in the thickness of the cerebral cortex, rather than cortical thickness itself, is most closely related to level of intelligence. Using a longitudinal design, we find a marked developmental shift from a predominantly negative correlation between intelligence and cortical thickness in early childhood to a positive correlation in late childhood and beyond. Additionally, level of intelligence is associated with the trajectory of cortical development, primarily in frontal regions implicated in the maturation of intelligent activity. More intelligent children demonstrate a particularly plastic cortex, with an initial accelerated and prolonged phase of cortical increase, which yields to equally vigorous cortical thinning by early adolescence. This study indicates that the neuroanatomical expression of intelligence in children is dynamic.  相似文献   
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