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211.
212.
A simple and yet reliable silver impregnation method, using potassium ferrocyanide, for demonstrating nervous tissue of the rat central nervous system embedded in paraffin or paraplast is described. The method reported here is compared and discussed with earlier techniques using potassium dicyanoargentate, potassium ferrocyanide and potassium ferricyanide. 相似文献
213.
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215.
216.
H Pedersen 《Journal of ultrastructure research》1970,33(5):451-462
217.
Ferredoxin from Bacillus polymyxa 总被引:5,自引:0,他引:5
Y I Shethna N A Stombaugh R H Burris 《Biochemical and biophysical research communications》1971,42(6):1108-1116
218.
The capillaries of the cardiac muscle were investigated in the goat by means of light microscopy, transmission electron microscopy and scanning electron microscopy, and the following results were obtained. The capillaries of the working cardiac muscles were numerous, arranged mainly parallel to the long axis of muscle cells and formed dense elongated networks. On the contrary, those of the terminal Purkinje fibers were relatively few in number, oriented in various directions and formed loose and circularly meshed networks surrounding the fibers. Such findings were discussed in correlation with the physiology and functional morphology of various types of the cardiac muscle cells. 相似文献
219.
220.
W. H. Trethowan 《BMJ (Clinical research ed.)》1970,4(5727):109-111
At Birmingham University since 1966 the major medical examinations began to be replaced by a process of continuous assessment. This is based on fairly frequent tests, usually at the end of each course, including short essay questions, multiple-choice questions, and tests of ability in wards and laboratory. At the end of the first final-year course 96 students underwent assessment. Of these 77 passed; 19 were referred for re-examination, of whom a further 12 passed subsequently. The scheme was found suitable by both teachers and external examiners. 相似文献