摘要:

SUMMARYA new instrument is described which permits automatic sampling of microscopic fields on sections. For this purpose a motor‐driven high‐precision specimen stage was fitted to a microscope. The motors are controlled by an electronic unit to permit the following modes of operation: (a) continuous operation by a four‐position joy‐stick switch for easy and rapid scanning of the preparation; (b) single‐step operation, where the specimen is displaced in either thex‐ or they‐direction by a preselected distance adjustable between 15 μm and 20 mm; (c) automatically repeated step operation, where the steps occur at intervals pre‐selectable between 0·5 and 34 sec; (d) scanning operation, where the specimen continuously moves along thex‐axis and is shifted to the next line at a preselected distance when the end of the sweep is reached. The details of principle and operation are presented together with a few typical exam

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02199.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SUMMARYThe following method is proposed for the analysis of the elliptically polarized light leaving a transparent, birefringent and dichroic specimen (in which the direction of maximum absorption coincides with either of the principal axes of refractive index), oriented with its optic axis at ± 45° relative to the transmission azimuth of the polarizer.Between the specimen and the rotatable analyser are two λ/4 plates; that nearer the specimen is fixed with its slow axis at ± 90° to the polarizer, while that nearer the analyser is rotatable. If the amplitude ratio of the components of light leaving the specimen is tan Y (Y being less than 45°), and their relative retardation is Δ°, at compensation the azimuth of the rotatable λ/4 plate will be Δ/2 (relative to its initial position orthogonal to the polarizer) and that of the analyser will be (45° ‐ Y), relative to the new azimuth of the rotatable λ/4 plate.Apart from involving minimal calculations, the method is capable of high precision with suitable equipment, since all critical settings can be made with the aid of a Nakamura half‐shade plate. Although so far used only in transmission polarization microscopy, the method is quite general and could be applied in any work involving

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02200.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SUMMARYUsing the mica‐replication technique of Hall, it is possible to visualize small, metal‐shadowed biological macromolecules. Consideration is given to the interpretation of micrographs obtained in this way, in order that molecular dimensions may be inferred.It is shown that the width of the shadow cast by a macromolecule can be measured precisely. A method is developed whereby the histogram of the experimentally determined shadow widths is interpreted by reference to computer‐generated histograms, based upon models of assumed dimensions. Results are presented illustrating the use of this new m

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02201.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SUMMARYQuartz glass capillaries of about 6 μm inside diameter were filled with fluorochrome solutions of accurately known concentrations and embedded as microscopical objects. The fluorescence intensity of a constant capillary volume has been found to be directly proportional to the amount of the excited fluorochrome in this volume within the fluorochrome concentration range 1:103. The capillary volume can be determined accurately by microinterferometric measurement of the inside diameter.The capillary section irradiated by the exciting light may be considered as very small in comparison with the total length of the capillary tube. During and after irradiation the excited part of fluorochrome solution is continuously renewed by convectional flow and diffusion. Therefore photodecomposition does not affect the measured fluorescence intensity, and the standard value remains unchanged even after numerous measurements. Thus, these fluorescence standards may be used to make successive calibrations of a microfluorometer and to check the constancy and reproducibility of measuring conditions. In certain circumstances it also permits measured fluorescence intensity to be interpreted in terms of the amount of fluorochrome or fluorescent substance.The results achieved with the capillary fluorescence standard are compared with those obtained by means of conventional methods. In addition, some essential optical properties of the microfluorometer equipment required for the proper use of this standard are discussed

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02202.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

摘要:

SUMMARYAn alternative cytochemical procedure is described for the periodic acid‐Schiff reaction (PAS) for adjacent glycol groups. This method appears to be as reliable as the PAS in its specificity and reproducibility, is simple to perform and its fully developed colour is more intense than the PAS reaction, although it fades after a few hour

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02203.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02204.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02205.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02206.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02207.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY

ISSN:0022-2720    

DOI:10.1111/j.1365-2818.1970.tb02208.x

出版商:Blackwell Publishing Ltd    

年代:1970

数据来源: WILEY