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- From: rfd@po.CWRU.Edu (Richard F. Drushel)
- Newsgroups: comp.graphics
- Subject: SUMMARY: 3-D reconstruction techniques (LONG--26K)
- Date: 8 Jan 1993 14:29:58 GMT
- Organization: Case Western Reserve University, Cleveland, OH (USA)
- Lines: 610
- Message-ID: <1ik356INN7dv@usenet.INS.CWRU.Edu>
- Reply-To: rfd@po.CWRU.Edu (Richard F. Drushel)
- NNTP-Posting-Host: thor.ins.cwru.edu
-
-
- SURVEY OF METHODS FOR 3-DIMENSIONAL RECONSTRUCTION 1991-1993
-
- compiled by Dr. Richard F. Drushel (rfd@po.cwru.edu)
- Department of Biology
- Case Western Reserve University
- Cleveland, Ohio 44106 USA
- (216) 368-3574
-
- Outline of Survey.
-
- I. USENET search.
- A. Dicer (Apple Macintosh).
- B. VoxelBox (80x86 family).
- C. AutoCAD (80x86 family).
- D. GVLware (SGI workstations).
- E. Khoros (DEC and other workstations).
- F. Miscellaneous software (workstations).
- G. Methods (platform-independent).
-
- II. Advertizement search.
- A. Minnesota Datametrics Corp.
- B. Eutectic Electronics, Inc.
-
- III. Biological literature search.
- A. Volumetric methods.
- B. Rotationally-symmetric or repeating
- structures.
- C. GLOM program.
- D. Ultrasound imaging.
- E. Automatic section alignment.
- F. Hand methods.
-
- ******************************************************************************
-
- I. USENET search. This summary is the result of the following request for
- information which I posted to comp.graphics on 31 December 1992:
-
- >From: rfd@po.CWRU.Edu (Richard F. Drushel)
- >Newsgroups: comp.graphics
- >Subject: 3D reconstruction from serial cross sections
- >Reply-To: rfd@po.CWRU.Edu (Richard F. Drushel)
- >Date: Thu Dec 31 16:07:57 1992
- >
- > For my Ph.D. dissertation, I did this the good old-fashioned
- >19th-century German anatomical way--by hand. Trace sections onto paper,
- >align using a light table, then reconstruct by isometric (orthogonal)
- >projection. Since I am also an illustrator, this turned out well. But
- >now that I am a postdoc, my new boss wants to use computer graphics
- >methods.
- >
- > The problem is, at least in the biological field, every paper
- >published in the last 2 years I have seen dealing with 3D reconstructions
- >uses either the 19th-century by-hand method, or else jerry-rigged hardware
- >and custom, hardware-specific software (read: not commercially available).
- >
- > I am prepared to admit that we biologists are not up to speed
- >on the current advances in such analyses (thus the preponderance of
- >jerry-rigged equipment). What, then, are more modern means of making
- >3D reconstructions from serial cross sections? E-mail please and I
- >will summarize for the net.
- >
- > I would be particularly interested in any solutions based
- >on the 80x86 computer family (for my owm practical needs), but please
- >feel free to describe any setup you wish which does this kind of
- >analysis. Many thanks in advance.
-
- The following newsgroups appear to be resources for information
- regarding 3-D reconstruction hardware, software, algorithms, and methods:
-
- alt.3d
- alt.cad
- alt.cad.autocad
- bionet.biology.computational
- bionet.neuroscience
- comp.graphics
- sci.image.processing
-
- My sincerest thanks to all those who responded! Each of you is credited
- after the material you submitted. Replies are grouped according to hardware
- platform; aside from minor editing for spelling and punctuation, the words are
- those of the respondents. I received responses from:
-
- ah395@cleveland.Freenet.Edu (Jeffrey T. Hansen)
- bridget@delphi.beckman.uiuc.edu (Bridget Carragher)
- cn09+@andrew.cmu.edu (Christopher Kalevi Nuuja)
- dona@zelda.nwra.com (Don Altman)
- dwilson@morph.EBME.CWRU.Edu (David Wilson)
- guy@trofis.tfrc.csiro.au (Guy Carpenter)
- hoberoi@limerick.cbs.umn.edu (Himanshu Oberoi)
- JKK103@PSUVM.PSU.EDU ("Mythos / Xcalbrin") {Joe Krug}
- jwp@world.std.com (john w poduska)
- martin@cs.curtin.edu.au (Martin Dougiamas)
- uselton@nas.nasa.gov (Samuel P. Uselton)
-
- ******************************************************************************
-
- A. Dicer (Apple Macintosh).
-
- The program Dicer, marketed by Spyglass, Inc. (217-355-6000), will do
- exactly what you want (and a lot more). It was designed specifically
- for studying 3-D data. Version 2.0 will be out in about a month. It
- will allow you to take arbitrary slices and iso-surfaces, as well as
- turn selected regions transparent and produce animations. The first
- version had a multi-page writeup in "Computers in Physics".
-
- Currently it only runs on Macintosh systems. Windows & Unix
- versions are coming.
-
- [From dona@zelda.nwra.com (Don Altman)]
-
- Spyglass, Inc.
- P.O. Box 6388
- Champaign, IL 61826
-
- Currently the program is in Version 1.12, available at $495. On February 1st,
- Version 2.0 goes on sale at $695. If you order Version 1.12 now, *BEFORE
- February 1st*, the upgrade to Version 2.0 is *FREE*.
-
- The program's preferred image input form is TIFF, but conversion programs
- are available for "almost anything" (quoth the sales rep :)
-
- ******************************************************************************
-
- B. VoxelBox (80x86 family).
-
- One very powerful technique for this type of reconstruction is called
- volume rendering. It basically takes the 2D slices and puts them
- together into a 3D cube of scalar values. It then allows you to associate
- colors and transparency values to the scalar values, and then the whole
- thing can be drawn in 3D.
-
- (Now for the sales push :-)) Volume renderers have traditionally only
- been available on workstations in the $5K - $10K per package price range,
- but my company, Jaguar Software, has recently started shipping a package
- for the PC for $495, or if you order before Jan 31 $325. The following
- stat sheet describes the product. If there are any other questions I can
- answer, please let me know.
-
- Product Name: VoxelBox
- List Price: $495
-
- System Requirements:
- - A 386 or higher based cpu, running Windows 3.x with at
- least 4MB of memory and a video board capable of displaying
- at least 256 colors.
-
- Volume Rendering:
- - High quality ray-tracer.
- - Fast Rasterizer.
- - Voxel based rendering with color/alpha mapping and lighting.
- - Advanced ray-tracing features include shadows, reflections,
- antialiasing and progressive refinement.
- - Volume cropping and slice planes for removing a corner of
- the volume.
-
- Color/Alpha Manipulation:
- - Create, save and import custom color and alpha maps.
- - Histogram Graph and orthogonal slice display aid color/alpha
- map selection.
- - Includes standard color maps such as hue circuit, heat ramp,
- gray scale, etc.
-
- Data Import:
- - Custom compressed volume format for saving disk space.
- - Readers for HDF and AVS volume files.
- - Custom reader handles byte, word, long, float and double
- based binary data, as well as ASCII data. Byte swapping and
- signed data are also supported.
-
- Data Export:
- - Save generated images in popular image file formats: TIFF,
- GIF, PCX, TGA, BMP, HDF.
- - Save imported volumes with custom compressed volume format,
- which also includes a comment field.
-
- Animation:
- - Create and save animations for viewing later.
- - Key frame scripting for simple animation set up.
- - Time line editor for more advanced control of animation
- scripts.
- - Automatic in-between frame generation.
- - Create animations in bounce or loop mode for continuous
- viewing.
- - Save animations as FLI, FLC, RL0, RLE or HDF movies.
- - Includes a redistributable RL0/RLE movie viewer for
- sharing results.
-
- Printing:
- - Prints to all Windows based color and b&w printers.
- - Output includes color/alpha mapping graphs and a set of axes.
-
- Other Features:
- - On-line hypertext help system.
- - Bounding box manipulator.
- - Extensive 8-bit pseudo color support.
- - Multiple views of the same volume.
- - Affordably priced.
-
- Jaguar Software Inc.
- 573 Main St., Suite 9B
- Winchester, MA 01890
- (617) 729-3659
-
- [From: jwp@world.std.com (john w poduska)]
-
- ******************************************************************************
-
- C. AutoCAD (80x86 family).
-
- I will say yes to your question, AutoCAD can take input from
- an ascii file of 3d points and create a mesh from them, but
- I'm going to add a huge disclaimer ...
-
- Right out of the box, it's kind of useless. To do what you're
- wanting to do, you're going to need to purchase an additional
- hunk of software, or write it yourself, of course. I'm assuming
- that you're taking your cross sectional data from your sea-slug
- bologna, and graphing it in some fashion? (sounds yummy, too bad
- finast doesn't stock it ...) If this is the case, you're going
- to need an interface to take the data and make it useable, because
- basically, autocad doesn't know what to do with it as raw x,y,z
- data, altho once the data is in, it can construct all sorts of neat
- 3d meshes and the like from the data.
-
- [From: ah395@cleveland.Freenet.Edu (Jeffrey T. Hansen)]
-
- ******************************************************************************
-
- D. GVLware (SGI workstations).
-
- If you can access an SGI then
-
- 1) Bring the images over to the SGI. You have to know the format they are in.
- The best form would be a LxM file of bytes. Each byte representing an
- intensity.
-
- 2) Then do
-
- cat img.1 img.2 imn.n > imgLxMxN.bin
-
- 3) view the "volume" using bob. This program is free and available from
- several sites. its home is at ftp.arc.umn.edu. This is very useful for
- viewing the whole volume. This of course does not reconstruct the image in
- the sense of extracting structural info, but by cleverly manipulating the
- colormap one can "see" surprising amounts of detail.
-
- I have helped a person who studies embryo development using confocal
- microscopy. He needed roughly 20 pictures (the N dimension) to get reasonable
- info. The more slices you have the better it is :)
-
- <begin blurb>
-
- The Army High Performance Computing Research Center (AHPCRC) and the
- Minnesota Supercomputer Center, Inc., have been developing a set of
- tools to work with large time dependent 2D and 3D data sets. In the
- Graphics and Visualization Lab (GVL) we are using these tools along
- side standard packages, such as SGI Explorer and the Utah Raster
- Toolkit, to render 3D volumes and create digital movies. A couple of
- the more general purpose programs have been bundled into a package
- called "GVLware".
-
- GVLware, currently consisting of Bob, Raz and Icol, is now available
- via ftp. The most interesting program is probably Bob, an interactive
- volume renderer for the SGI. Raz streams raster images from disk to
- an SGI screen, enabling movies larger than memory to be played. Icol
- is a color map editor that works with Bob and Raz. Source and
- pre-built binaries for IRIX 4.0.1 are included.
-
- To acquire GVLware, anonymous ftp to:
- machine - ftp.arc.umn.edu
- file - /pub/gvl.tar.Z
-
- <end blurb>
-
- [From: hoberoi@limerick.cbs.umn.edu (Himanshu Oberoi)]
-
- ******************************************************************************
-
- E. Khoros (DEC and other workstations).
-
- Or try Khoros. This is a very very good image analysis package and recently
- acquired 3D capabilities. The package is _HUGE_ about 150Mb of disk but very
- versatile and OOP based. Khoros would be a good first bet. The DECstation
- 5000/200 would just about work. Does it have DECWindows? You will need that
- for sure. The ftp site for khoros is
-
- pprg.eece.unm.edu [129.24.24.10]: /pub/khoros - *Khoros image processing
-
- the package is reallly very big. Would take you approx 2-4 hours to ftp it
- over. Try looking in your local area, especially on a computer science
- machine and get the executables :).
-
- In any case you will need lots of memory + disk on your machine.
-
- [From: hoberoi@limerick.cbs.umn.edu (Himanshu Oberoi)]
-
- ******************************************************************************
-
- F. Miscellaneous software (workstations).
-
- (1) If you cannot get your hands on an SGI then if you can get a
- SUN/RS6000/HP etc then get some of the image viewing programs from
- ftp.ncsa.uiuc.edu (the good ones are XDataSlice and PolyView (SGI-specific).
- XDataSlice does volume rendering slicing and contouring. I could send you
- some programs that can get from the NxN byte to something XDataSlice
- understands.
-
- As for XDataSlice from (ftp.ncsa.uiuc.edu) UNIX/XDataSlice/XDS1.2 has a
- DEC Ultrix executable, and XDS2.0b has a DEC 3100 executable. Source is
- also present for the 1.2 version.
-
- And finally if you have an IBM RS6000 you can get DataExplorer from IBM which
- is a OOP type program and is very powerful. Again I could send you some
- macros etc to get your data into it. DataExplorer is available for other
- platforms SGI/HP/SUN too from IBM.
-
- There is a commercial product VoxelView. Runs on SGI and SUN.
-
- [From: hoberoi@limerick.cbs.umn.edu (Himanshu Oberoi)]
-
- (2) My first publication (while still a grad student) was "Optimal Surface
- Reconstruction from Parallel Contours," in CACM Oct. 1976. (Fuchs, Kedem &
- Uselton). I haven't worked on this problem for awhile, but I do try to keep
- up on developments. Our software was written in FORTRAN on a PDP-11 and I've
- moved three jobs since then so I don't still have it. In fact, I've re-
- implemented it twice as consultingjobs for commercial outfits' internal use.
-
- Ken Sloan, now on faculty at U. Alabama Birmingham, had a package while
- he was in Washington that went further (and was more thoroughly "developed"),
- handling branching problems and fitting a smooth spline patch surface over the
- initial triangulation. His email is sloan@cis.uab.edu, and he can tell you
- current status of that software. At one point I think it was ftp-able. (He
- often reads this group and may respond himself.)
-
- Another possibility is a small company called Surgicad. While still a
- grad student, I helped port our software to a Data General machine in a cell
- biology lab at Southwest Med in Dallas. Two MD's (interns? post-docs? anyway
- they were slave labor like me) worked as the system hackers in this lab. One
- of them, Dan Schlusselberg is now Pres and CTO of Surgicad. They sell systems
- that may do what you want. My contact info (may be out of date):
-
- Surgicad Corp. (603) 448-4900
- Chiron Springs (603) 448-0179 fax
- 115 Etna Rd.
- Lebanon, NH 03766
-
- [From: uselton@nas.nasa.gov (Samuel P. Uselton)]
-
- ******************************************************************************
-
- G. Methods (platform-independent).
-
- (1) A method we've had reasonable success with here at the Pittsburgh
- Supercomputing Center is this:
-
- For each cross section, create a 2D grid of density values (or assign
- values for each boundry you are interested in). Values outside the cross
- section are 0 (and be sure to have 0's completely surrounding the cross
- section).
-
- Put the 2D grids togeather into a 3D volume and use standard volumetric
- techniques on it. (i.e. isosurface at the density/boundry thresholds you
- are interested in, volumetric rendering, colored slice planes, etc.).
-
- [From: Christopher Kalevi Nuuja <cn09+@andrew.cmu.edu>]
-
- (2) I have seen applications in both the medical field and the geology/
- mining discipline which use serial cross sections to reconstruct solid
- objects. I have in my archive (at home) a paper describing a method for
- dealing with some of the tricky bits - where bodies join and divide - which I
- always figured would be a good place to start if I was ever asked to implement
- such a beastie. Ref can be provided should you request it.
-
- [From: Guy Carpenter <guy@trofis.tfrc.csiro.au>]
-
- (3) I don't know if this is what you meant, but I saw on Beyond 2000 on the
- Discovery channel, once about people doing 3-d cut away views, etc...on the
- computer for dissection in pre-med classes and such. What they had done was
- take very thin slices of the tissue, photograph it, and then load them into
- the computer database. The end result (using appropriate software of course)
- was a really detailed 3-d cutaway /peel away viewing of structures.
-
- [From: "Mythos / Xcalbrin" <JKK103@PSUVM.PSU.EDU> {Joe Krug}]
-
- ******************************************************************************
-
- II. Advertizement search. I searched through the 12 issues of Trends in
- Neurosciences (TINS) Volume 15 (1992).
-
- A. Minnesota Datametrics Corporation
- 1000 Ingerson Road
- St. Paul, MN 55126
- (612) 482-7938 FAX (612) 490-9717
- TINS 15: lvii (1992)
-
- Two systems are available:
-
- (1) 80386/80486-based system with color VGA monitor.
-
- A special electronic instrument is attached to the microscope stage;
- you move the stage to trace the object, and the instrument digitizes the
- (x,y) coordinates (5 micron resolution).
- Software displays level curves in isometric (orthogonal)
- projection--*DISTORTION*. Uses VGA/SVGA color monitors.
- Software can perform simple rotations, translations, feature counts,
- color different features.
- Cost: stage instrument $3500, software $1450.
-
- (2) SGI workstation-based system.
-
- Input: either greyscaled images or data in a variety of formats.
- Output: shaded surfaces, areas, volumes. *TRUE PERSPECTIVE*
- Cost: software $8000, SGI workstation $18,000-$24,000.
- Also available: a translator program to convert the software database
- format into AutoCAD format. If you have AutoCAD, you can use your 80386/80486
- computer instead of the SGI workstation for output. In this case, you just
- buy the $8000 software.
-
- ******************************************************************************
-
- B. Eutectic Electronics Corp.
- Department A01
- 8608 Jersey Court
- Raleigh, NC 27613
- (919) 782-3000 FAX (919) 782-9913
- TINS 15: xli (1992).
-
- (1) 80386/80486-based system with color VGA monitor.
-
- Consists of a vector graphics processor, a special color vector graphics
- screen, and a special digitizing tablet with mouse. Software package contains
- tracing routines, color editors, and output routines to calculate volumes and
- areas.
- Input: stack of prints *WHICH MUST BE TRACED* on the special tablet--no
- provision for in-microscope scanning.
- Output: outlines of reconstruction only (no shading). *TRUE
- PERSPECTIVE*
- Cost: installed yourself, you provide the base computer, $8000 for the
- 3 special hardware pieces and the software.
-
- ******************************************************************************
-
- III. Literature search. I searched Biological Abstracts Volume 93 (1992)
- under keyword RECONSTRUCT* for articles with 3-DIMENSIONAL in the title or
- abstract. This is *LONG* and perhaps only of interest to biologists, so
- if you wish, you may hit "n" now :)
-
-
- A. Volumetric methods.
-
- (1) Takersley, R.A., and R.V. Dimock (1992). Quantitative analysis of the
- structure and function of the marsupial gills of the freshwater mussel
- Anodonta cataracta. Biol. Bull. 182: 145-154.
-
- Examined and quantified volumetric changes in gill water tubes.
- Serial frontal sections @ 10 microns, photograph & align every 5th
- section.
- Digitize with Summagraphics digitizer (25 sections/sample) on Zenith
- Z-386SX computer.
- Analyze with PC3D (Jandell Scientific) to determine volumes.
- Final reconstruction was 1.25 mm-thick slice of gill.
- Output: *NO PICTURES SHOWN*
-
- ******************************************************************************
-
- B. Rotationally-symmetric or repeating structures.
-
- (1) Baker, T.S., Newcomb, W.W., Olson, N.H., Cowsert, L.M., Olson, C., and
- J.C. Brown (1991). Structures of bovine and human papillomaviruses: Analysis
- by cryoelectron microscopy and three-dimensional image reconstruction.
- Biophys. J. 60: 1455-1456.
-
- Digitized images of whole-mount EM spreads of virus particles.
- Technique of common lines and Fourier-Bessel transformations.
- *ONLY WORKS ON ROTATIONALLY-SYMMETRIC PARTICLES*
- Used VAX/VMS 8550 with custom FORTRAN-77 programs from:
-
- Fuller, S.D. (1987). The T=4 envelope of Sindbis
- virus is organized by interactions with a complementary
- T=3 capsid. Cell 48: 923-934.
-
- Output: Grey-scaled photographs of solids.
-
- (2) Dokland, T., Lindqvist, B.H., and S.D. Fuller (1992). Image
- reconstruction from cryoelectron micrographs reveals the morphopoietic
- mechanism in the P2-P4 bacteriophage system. EMBO J. 11:: 839-846.
-
- Same techniques, different virus.
-
- (3) Frank, J., Penczek, P., Grassucci, R., and S. Srivastava (1991).
- Three-dimensional reconstruction of the 70S Escherichia coli ribosome in ice:
- The distribution of ribosomal RNA. J. Cell Biol. 115: 597-606.
-
- Digitize micrographs on flatbed microdensitometer (PDS 1010A,
- Perkin-Elmer Corp., Norwalk, CT).
- Align on SGI workstation (Silicon Graphics, Mountain View, CA).
- 3-D contours from SGI workstation using INSIGHT software (Biosym
- Technologies, San Diego, CA).
- Same techniques, different hardware and software.
-
- (4) Zedzik, J., O"fverstedt, L.-G., and U. Skoglund (1992). Three-
- dimensional reconstruction of bovine intradural spinal root myelin by electron
- microscope tomography. J. Neurosci. Res. 31: 387-393.
-
- Micrographs scanned by Optronics P-1000 optical drum scanner.
- VAX 11/750 and Convex C210 computer analysis of repeating structures.
- Output: Balsa wood models made from level curve printer output.
-
- ******************************************************************************
-
- C. GLOM program.
-
- (1) Faraj, A.H., Morley, A.R., and S. Coleman (1991). Three-dimensional
- reconstruction of juxtaglomerular apparatus (JGA) in five-sixth nephrectomized
- rats. APMIS 99: 1129-1141.
-
- 1 micron sections/toluidine blue stain/each 5th section taken for
- reconstruction.
- Photograph @ 250X, enlarge to 16.5x21.5 cm, hand-trace contours in
- different colored inks on the enlargements.
- GLOM program to digitize tracings with mouse, reconstruct, rotate,
- translate. Program described in:
-
- Coleman, S.Y. (1986). Statistical computer
- graphics and morphometry in 3-dimensional reconstruction
- of serial sections of glomerulus. Ph.D. thesis, University
- of Newcastle-Upon-Tyne.
-
- *COMPUTER TYPE/ARCHITECTURE/MPU NOT STATED*
- Output: Produces only level curves; no removal of hidden lines, etc.
- Different structures printed in 4 colors on dot-matrix printer.
-
- (2) Faraj, A.H., Lindop, G.B.M., Morley, A.R., and S. Coleman (1992).
- Three-dimensional reconstruction of human juxtaglomerular apparatus (JGA).
- APMIS 100: 29-38.
-
- Same techniques as above.
-
- ******************************************************************************
-
- D. Ultrasound imaging.
-
- (1) Rosenfield, K., Losordo, D.W., Ramaswamy, K., Pastore, J.O., Langevin,
- R.E., Razvi, S., Kosowsky, B.D., and J.M. Isner (1991). Three-dimensional
- reconstruction of human coronary and peripheral arteries from images recorded
- during two-dimensional intravascular ultrasound examination. Circulation 84:
- 1938-1956.
-
- Ultrasound images of arteries recorded on VHS video tape.
- Digitized on 80386-PC/AT with D/A converter (ImageComm Systems, Santa
- Clara, CA).
- Images processed with SciView workstation (ImageComm Systems) using
- OMNIVIEW software (Pura Labs, Brea, CA).
- Specific for dealing with grey-scaled image analysis.
- *USED CATHETER BORE FOR ALIGNMENT*
- Output: 3-D grey-scaled images.
-
- ******************************************************************************
-
- E. Automatic section alignment.
-
- (1) Hibbard, L.S., Arnicar-Sulze, T.L., Dovey-Hartman, B.J., and R.B. Page
- (1992). Computed alignment of dissimilar images for three-dimensional
- reconstructions. J. Neurosci. Methods 41: 133-152.
-
- 60-80 nm EM sections, to span total distance of 100 microns.
- 4 out of every 10 sections used for processing.
- Digitized on Optronics P-1000 scanning microdensitometer @ 100 micron
- resolution.
- DIANA image analysis system on DEC VAX computers/workstations (J.
- Neurosci. Methods 26: 55-74 (1988)).
- 3-D graphics using either GRAMPS (Comput. Graphics 15: 133-141 (1981))
- or MOVIE.BYU (custom software at BYU)
- or author's (TLS) custom program for Evans & Sutherland PS390
- graphics system.
- Output: grey-scaled solid images.
- *GOOD THEORY PAPER*
-
- ******************************************************************************
-
- F. Hand techniques.
-
- (1) Senoh, K., and J. Naito (1991). A WGA-HRP study of the fiber
- arrangement in the cat optic radiation: A demonstration via three-dimensional
- reconstruction. Exp. Brain Res. 87: 473-483.
-
- Trace section outlines on clear animation cels.
- Stack cels, each separated by distance proportional to thickness.
- Hang a blank cel in front of the stack.
- Look through stack and trace outlines in perspective.
-
- (2) Pignot-Paintrad, I., and C. Bressac (1992). Rapid three-dimensional
- reconstruction at the light microscopic level and a technique for re-embedding
- the same semithin sections for electron microscopic examination. Biotech.
- Histochem. 67: 55-57.
-
- Hand reconstruction of plastic sections temporarily mounted (drawing
- tube on microscope).
- When you find out where you are, liberate desired sections, reembed, and
- thin section.
-
- ******************************************************************************
-
- END OF SUMMARY.
- --
- Richard F. Drushel ****** Ph.D. in Developmental Biology as of 4:45 PM 9211.20
- rfd@po.cwru.edu ** Cleveland FreeNet ** Co-Sysop, Coleco ADAM Forum ** Go Z80!
- .............................................................................
- After 13 years of CWRU, gainfully employed making bologna slices of sea-slugs!
-