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991.
The ultrastructure of cytolytic T lymphocytes adhered to the surface of target cells was investigated at different periods after start of interaction. Fifteen-minute incubation led to increase of number of Golgi apparatus cisternae and vacuoles. After 30 min incubation Golgi apparatus become oriented to the contact area. If several lymphocytes adhered to one target cell the Golgi apparatus of each of them was oriented toward the contact area. If one lymphocyte adhered simultaneously to two target cells its Golgi apparatus was oriented toward both target cells. Giant Golgi apparatus vacuoles were formed 30 to 60 min later and then moved to plasma membrane of lymphocyte and then the content of those vacuoles moved to the intercellular space between a cytolytic T lymphocyte and a target cell. The period required for the hypertrophy and change of orientation of Golgi apparatus is supposed to represent the “mobilization” step of a medium-sized and small killer lymphocyte. 相似文献
992.
993.
J Tsunehiro K Okamoto Y Furuyama T Yatake T Kaneko 《Bioscience, biotechnology, and biochemistry》1999,63(9):1515-1521
The digestibility of the hydrogenated derivative of an isomaltooligosaccharide mixture (IMO-H) was investigated. In an in vitro experiment, the digestibility of IMO-H was examined by models of the digestive system. IMO-H was resistant to two types of alpha-amylase and to artificial gastric juice. Enzymes in the rat small intestinal mucosa hydrolyzed tri-, tetra- and higher saccharide alcohols to disaccharide alcohol, removing successive glucose units from the non-reducing ends of the chains. The hydrolysis ratio for IMO-H was intermediate between the values for maltose and maltitol. In an in vivo study, growing rats were fed on an experimental diet containing IMO-H, maltitol, or hydrogenated palatinose in the range from 5% to 20%. The growth parameters of the rats fed on the test sugar show that the availability of IMO-H was about 1.2 to 1.25 times that of maltitol or hydrogenated palatinose. 相似文献
994.
995.
996.
997.
998.
Polypeptide components of an excitable plasma membrane 总被引:4,自引:0,他引:4
999.
The copigment present in the crystalline blue pigment isolated from Blue Boy cornflowers (Centaurea cyanus L.) was identified as apigenin 4′-O-β-glucoside 7-O-β-d-glucuronide. The NMR spectra of aryl glucuronides are discussed. 相似文献
1000.
Phenylacetic, 3-phenylpropionic, -hydroxyphenylacetic and 3 (-hydroxyphenyl) propionic acids together with the series of C2 to C6 saturated fatty acids previously reported in the anal sac secretion of the red fox () are identified as constituents of the anal sac secretion of the lion (Panthera leo). All these compounds are also observed in the anal sac secretion of the red fox using gas chromatography. The aerobic microflora of red fox and domestic dog () anal sac secretion samples invariably consisted predominantly of and . The hypothesis that the secretion volatiles so far identified may be microbiologically produced is examined. 相似文献