Procedures for Three-Dimensional Reconstruction from Thin Sections with Electron Tomography

摘要: Electron tomography (ET) is a method for three-dimensional (3-D) reconstruction of single, transparent objects from series images (i.e., tilt series) recorded with transmission electron microscope (EM) (Fig. 4.1). The related to the procedures used in medical tomography. 3-D reconstructions are usually computed digitized after radial weighting scheme has been applied Fourier-transformed data. ET can be reconstruct any object that enough projection imaging EM. This means specimens biological origin available reconstruction, whereas, e.g., colloidal gold particles not. An ET-calculated map could based on projections have visualized by EM several different ways, i.e., stained or unstained objects, at energy loss levels embedded media. combined analysis structure, imaged thus become very informative. general applicability also it not restricted symmetrical regularly arranged nor preferred orientations support grid. In its present state, allows reproducible single molecular resolution range 5 nm, complex cellular specimens. For isolated free interfering substances, somewhat higher achieved. covers intermediate where there no other physical technique analyze complexes.