Formation and evolution of the Archean continental crust of China:A review

The mainland of China is composed of the North China Craton,the South China Craton,the Tarim Craton and other young orogehie belts.Amongst the three cratons,the North China Craton has been studied most and noted for its widely-distributed Archean basement rocks.In this paper,we assess and compare the geology,rock types,formation age and geochemical composition features of the Archean basements of the three cratons.They have some common characteristics,including the fact that the crustal rocks prior to the Paleoarchean and the supracrustal rocks of the Neoarehean were preserved,and Tonalite-Trondhjemtite- Granodiorite (TTG)magmatism and tectono-magmatism occurred at about 2.7 Ga and about 2.5 Ga respectively.The Tarim Craton and the North China Craton show more similarities in their early Precambrian crustal evolution.Significant findings on the Archean basement of the North China Craton are coneluded to be:(1)the tectonic regime in the early stage (>3.1 Ga)is distinct from modem plate tectonics;(2)the continental crust accretion occurred mostly from the late Mesoarchean to the early Neoarehean period;(3)a huge linear tectonic belt already existed in the late Neoarchean period,suggesting the beginning of plate tectonics;and (4)the preliminary cratonization had already been completed by about 2.5 Ga. Hadean detrital zircons were found at a total of nine locations within China.Most of them show clear oscillatory zoning,sharing similar textures with magmatic zircons from interrnediate-felsic magmatic rocks. This indicates that a fair quantity of continental material had already developed on Earth at that time.

Apoptosis of human colon carcinoma HT-29 cells induced by ceramide

瞄准：在人的冒号癌 HT-29 房间上调查外长的导致 ceramide 的 apoptosis 的效果。方法：轻显微镜，传播电子显微镜和荧光显微镜被用来在 HT-29 房间观察 apoptosis 的形态学变化。Agarose 胶化电气泳动被执行检测 DNA 碎片。Mitochondrial 功能被 MTT 试金检测。Bcl-2 家庭基因成员的 mRNA 表示被反向的抄写决定聚合酶链反应(RT-PCR ) 试金。结果：在 C2-ceramide 治疗以后， apoptosis 的典型特征例如原子染色质破裂， apoptotic 身体和 DNA 梯子，能被观察。在到为 12 和 24 h 的 50 micromol/L C2-ceramide 的暴露以后，房间 apoptosis 分别地是 64.1% 和 81.3% ，它有一时间 -- 并且剂量效果关系。Mitochondrial 功能开始在暴露以后从 6 h 减少到酰基鞘氨醇。同时，起来调整或下面调整的酰基鞘氨醇 Bcl-2 家庭基因成员的 mRNA 表示。结论：酰基鞘氨醇由影响 Bcl-2 家庭基因成员的表示并且影响 mitochondrial 功能导致人的冒号癌 HT-29 房间的 apoptosis。