Methodologic aspects of the x-ray endoscopic study of the pancreatobiliary system]

Methodological variants of roentgenoendoscopic investigation of the pancreatobiliary system were worked out on the basis of a combination of various methods of contrast studies of the ducts and fibroduodenoscopy. Possibilities of their use were shown with respect to a clinical situation. Investigations of 240 patients led to the conclusion that the use of the above variants of roentgenoendoscopic investigation increased diagnostic and therapeutic efficacy in diseases of the pancreatobiliary system.     

The value of the x-ray study method in the diagnosis of celiac-sprue]

The authors describe some features of x-ray symptoms of Gee-Herter disease with relation to severity and a period of disease. Altogether 106 adult patients with this disease were followed up, of them 78 patients with diagnosis of Gee-Herter disease, confirmed by histology of intestinal biopsy specimens, were selected for analysis. Three groups of patients with different x-ray symptoms were singled out. Some distinctive features of differential diagnosis and complications of Gee-Herter disease in adults were noted.     

An x-ray study of the subcutaneous tissue using an artificial method of providing contrast]

The paper is concerned with the main methodological principles and potentialities of a radiocontrast study of subcutaneous fat to detect pathological changes in it. The proposed method consists in slow administration in the middle fat layers of 20-25% solution of verografin from not less than two points, and subsequent roentgenography in a necessary projection. The method was used in 15 patients with various orthopedic diseases for diagnosis of inflammatory, tumorous and degenerative-dystrophic diseases.     

Application of x-ray analysis for the study of the orientation in DNP films]

A planar texture in dried film samples of DNP was found by X-ray study. Axes of DNA macromolecules are located in the film plane and the 77 A reflection is directed along this axis. Periodic structures corresponding to 55 and 34 A are packed parallel to the film plane. The results obtained do not contradict with a supercoil DNP model, however they all allow other possible packing models of DNP molecules, in particular, histone layers alternating with DNA layers in oriented films.     

Experience in the use of synchrotron radiation for the x-ray study of biopolymers]

The results of methodical work, carried out on the sources of synchrotron radiation (SR) with the aim of using SR as a powerful source of X-rays for studying biopolymer structure, are presented. The questions of monochromatization are considered. The technique designed for photoregistration of diffraction patterns within the wide range of scattering angles is described. X-ray diffraction patterns of feather ceratin, collagen and striated muscle are obtained with exposure periods ten times less than those in the case of X-ray tubes. The high resolution of diffraction lines, the absence of parasitic phone and the presence of reflections within the wide range of scattering angles are characteristic of these patterns.     

A field method for the cephalometric x-ray study of skulls in early Nubian cemeteries

The cephalometer, a clinical and research instrument employed by the orthodontic profession to record standardized x-rays of the human skull, has been modified for research work in remote areas where the usual laboratory facilities are not available. This cephalometer was specifically designed to record cephalograms (head radiographs) on the living Nubian population and their extensive skeletal record. The cephalometer consists of a light, portable tripod stand and an aluminum beam to which is attached at one end a Wehmer cephalostat (head holder), and on the other end an isotope radiation source. Hence, the radiation source and the cephalostat were held in the standard relationship of five feet from source to the mid-saggittal plane of the cranium. Ytterbium-169, with a half life of 32.5 days, was used to expose the film. The isotope and the use of the new Experimental Polaroid X-ray Film permitted the x-ray examination of Nubian skulls with no conventional power source or darkroom facilities.     

Preliminary electron microscopic and x-ray study of the crystalline protein of diphtheria toxin]

The authors present the results of the electron microscopic and roentgenological study of the crystalline protein of diphtheria toxin. On the basis of direct measurements of the crystal image and diffraction pictures it was possible to calculate the interplane distances of the placement of molecules in the crystal. Examination in polarization microscope showed that the crystals were optically uniaxial with a direct extinction and a positive character of elongation. Molecular aggregates revealed in the protein molecules resembled the caudal part of the bacteriophage by structure.     

The supramolecular organization of oxyhemoglobin in erythrocytes. A small-angle x-ray scattering study]

From X-ray scattering diagrams of concentrated solutions of hemoglobin the pair-correlation function of the molecules is calculated. At a concentration of 324 g/l the distance between neighbouring molecules amounts to 65 A. The number of direct neighbours of one molecule is 9. The pair-correlation function cannot be described by the assumption of a lattice-cell-model; therefore, a lattice-vacancy-model with fluid order is proposed.