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71.
目的:研究外源笥三磷酸腺苷(adenosine triphosphate,ATP)是否能够进入低温保存大鼠肝脏细胞内。方法:采用大鼠肝脏持续低温机器灌流保存模型,利用放射自显影技术判定[α-^32P]ATP是否进入细胞内。结果:灌流液中不加[α-^32P]ATP的A组光镜照片显示大鼠肝细胞内外均未见特异性标记银粒显影,而灌流液中含37MBq[α-^32P]ATP的B组光镜照片显示大鼠肝细胞内可见多个大小不等的[α-^32P]ATP自显影银粒分布,而肝窦及肝小叶中央静脉等血管内则几乎无黑色自显银粒分布。结论:外源性ATP能够进入低温保存大鼠肝细胞内。 相似文献
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74.
Hans J. Seitz Wilhelm Krone Harald Wilke Wolfgang Tarnowski D. Carsten B. Dunkelmann A. Harneit 《Pflügers Archiv : European journal of physiology》1981,389(2):115-120
The effect of acute cold exposure on the concentration of glucagon in the blood was investigated in man and in intact and adrenalectomized rats.In man fasted overnight acute cold exposure, which caused a twofold increase in O2-consumption resulted in a rapid rise in plasma glucagon. The levels of insulin and blood glucose remained unaltered, while the concentration of serum free fatty acids and -hydroxybutyrate increased.In fasted intact rats acute cold exposure lead to similar effects. A close parallelism between the rise in plasma glucagon and the concentration of hepatic cycloAMP was observed. Adrenalectomy did not impair the cold induced rise in plasma glucagon and hepatic cycloAMP.It is concluded that acute cold exposure caused a rapid rise in the concentration of plasma glucagon leading to an increase in the concentration of hepatic cycloAMP, thus enhancing the rate of hepatic gluconeogenesis and ketogenesis. As these alterations were similar in the absence of glucocorticoids and medulla-derived catecholamines, it is suggested that glucagon may play a role in the metabolic adaptation to acute cold exposure. 相似文献
75.
Gregory K. Snyder Caroline Farrelly Joseph R. Coelho 《European journal of applied physiology》1992,65(2):158-163
Summary The effects of changes in oxygen supply and oxygen demands on fiber cross-sectional areas, capillary dersities and capillary to fiber ratios were determined in three skeletal muscles of rat. The muscles examined were the vastus lateralis, soleus, and diaphragm. Reduced oxygen supply was produced by subjecting rats to ambient hypoxia, and increased oxygen demands were produced by subjecting rats to low ambient temperatures or treatment with thyroxin. Capillaries were visualized by injecting fluorescent dyes into the circulation. Muscles were quick frozen at resting lengths to preserve normal fiber geometry and were subsequently sectioned on a cryostat. All of the muscles sampled from animals in the experimental groups had elevated capillary densities. However, capillary to fiber ratios were not increased significantly in any muscle, for any experimental condition. Thus, all of the observed differences in capillarity were due to changes in the intrinsic rate of muscle fiber growth. Further, the relations of capillary density and capillary to fiber ratio to fiber area were the same as those obtained during normal maturation, suggesting that capillary growth is closely linked to the intrinsic rate of fiber growth. 相似文献
76.
Blood storage and blood transfusion have beenimportantclinical work.In recentyears,the demandfor the quality of blood transfusion is getting higher.Great progress has been made in blood storage tech-nique and more and more reports on change in bloodcomponents during storage have been published.However,reports on dynamic changes in blood com-ponentsin bank- stored blood are stillrare.The paperinvestigated the dynamic change of blood componentsF :c and AT- in blood stored in blood bank un-der… 相似文献
77.
伤寒史学研究成果简述 总被引:1,自引:0,他引:1
万晓刚 《Zhonghua yi shi za zhi (Beijing, China : 1980)》2000,30(4):211-214
建国以来有关伤寒史学的研究成果表现在相关人物、相关著作、相关事件、学术关系及阶段特征五个方面。前期研究成果 ,尚不足以充分展示伤寒学历史地位和现实意义 ,更无充分依据昭示其未来之发展方向 ,因而有必要继续深入开展伤寒史学研究 相似文献
78.
We found two patterns of leptomeningeal storage that reflect two basic visceral storage patterns in Fabry disease. (i) A generalized-type leptomeningeal storage pattern, affecting all main leptomeningeal cell types (external arachnoideal epithelium, fibroblasts, vessel wall elements), was a consistent finding in three cases of classical generalized visceral phenotype. (ii) A localized leptomeningeal storage pattern was expressed, to a high degree, solely in the external arachnoidal epithelium; this pattern was found in one case with the variant visceral-restricted-type storage (confined to the cardiocytes). Thus, the external arachnoidal epithelium may be particurlarly susceptible to Fabry lipid storage, probably caused by a distinctly larger sustained lysosomal lipid load as compared to other cell types. 相似文献
79.
The relationship between physical stability of freeze-dried cakes and protein stability during storage was studied using -galactosidase as a model protein and inositol as an excipient. Amorphous samples freeze-dried from solutions containing the enzyme and various concentrations of inositol in sodium phosphate buffer (50 mM, pH 7.4) were stored for 7 days over P2O5 at 40 to 70°C. Structural collapse and inositol crystallization were observed in some of the samples, depending on the formulation and storage temperature. The physical stability of freeze-dried samples was also studied by differential scanning calorimeter (DSC). Inositol showed a protein-stabilizing effect when its amorphous form was retained during storage, regardless of structural collapse. However, crystallization of inositol during storage removed its stabilizing effect. Addition of water-soluble polymers such as dextran, Ficoll and carboxymethyl cellulose sodium salt (CMC-Na) preserved activity of the enzyme by preventing inositol crystallization. 相似文献
80.
Mucolipidoses II is a rare lysosomal storage disorder with autosomal recessive inheritance. There cases with typical clinical
features in early infancy like coarse facial features, severe psychomotor retardation and joint contractures are being reported.
All the cases had no mucopolysacchariduria. These cases had normal values of lysosomal enzymes in leucocytes but markedly
increased values in serum thus confirming mucolipidoses II. Despite the fact that there is no specific treatment, genetic
counselling and prenatal diagnosis is indicated. 相似文献