Antall József szerk.: Orvostörténeti közlemények 92. (Budapest, 1980)

TANULMÁNYOK - Miczbán Izabella: A sejtkép személetének alakulása a XX. században (magyar és angol nyelven)

introduced into common medical knowledge the view of functional anatomy. Following Galileo's principle, Huzella's slogan for morphologic researches was "to perceive the visible and to make visible the invisible". [6] This was the guiding principle of those qualitative researches which aimed at a fresher, livelier representation, a more spectacular approach of cells. A more elaborated and grounded form of examination for surviving cells and tissues is the tissue culture. On institutional basis, this process was introduced in Hungary by Huzella and his circle. The observations on the life processes of the cells were microcinematographically recorded, working with time contraction in case of slow processes and with reduced explosure time in case of rapid events. The projection of these films had the effect of revelation at that time, and brought international fame as well, after the stained images classical histology had produced. [6, 9] The value of observations on living cells spared by microtechnical interventions now became evident. The microscopic image of native preparations however, is very poor in contrast since these preparations affect upon the phase of the light which is a character our eyes are less sensitive of, unlike stained preparations which change the intensity of light of which our eyes are more sensitive. There was need for a process which could transform small differences of phase into differences in intensity. This problem was solved by Zernike's phase contrast process (1935) which resulted in more contrastful images by way of inserting a phase lamella into the objective of the microscope. The elaboration of the phase contrast theory gave way to further development. It became known that in all the microscopes the image is a result of the interference of inflected and non-inflected beams of light. While with the traditional microscope the object itself dissolves the light supplying waves into partial waves, in the newly constructed interferential microscope (1955, 1971) they are dissolved into two or more coherent partial waves by an apparatus indépendant of the object. In this case not only the changes indicating sudden width and break are contrastful but continuous transitions become visible as well. [3] Besides the so far mentioned qualitative, direct, physical methods, still within microscopic dimensions, we must speak of cytochemistry which also has a qualitative character but works with indirect, chemical methods. Its task is partly to discover the mechanism of microtechnic processes, its primary interest, however, lies in the finer chemical composition, structure and physiology of the cell. [12, 15] The purpose of "visible invisibility" received new possibilities by the opening up of submicroscopic dimensions with indirect and direct methods. The instrument of the first is polarized optical analysis (1938) and roentgenospectograph (1939), of the latters electron microscopic examination (1932). The transmissionary electron microscope was constructed on the analogy of light microscope. In keeping with the Abbé formula the solubility of electron microscopes is 0,1—0,2 nanometer as opposed to the 200 nanometer solubility of the light microscope. In the scanning electron microscope the concentrated beam of electron rays is forced on a sweeping movement with the help of deflectings reels. [19] Thus the surface of the investigated object is scanned point by point. Upon the effect of the electrons splashed into the surface of the object, secondary electrons of similar energy leave off the object. These are gathered by the detector and the qualitative changes transform into electric sign. From the intensified signs got into the cathode tube image