The optimum intensities for multiple static multileaf collimator field compensation

A method of determining the optimum beam intensities for compensation using multiple static multileaf collimator fields is presented. In this method a histogram of the number of beam pixels against beam intensity is generated for the intensity-modulated beam (IMB). The intensity of each beam to be used is chosen to minimize the mean square deviation between each bin in the histogram and the closest beam intensity. This method has been applied to sample IMBs possessing one maximum and two maxima. For both cases, the use of uniform beam intensity increments is shown to be close to optimal. In the case with two maxima, the efficacy of irradiating both peaks simultaneously, rather than separately, has been studied and shown to be of potential benefit. The optimum intensities for an IMB for breast radiotherapy are also presented.     

Transport of fatty acids in the bloodflow as the major function of lipoproteins

System of lipoproteins serves for the transport of fatty acids in the blood. Triacylglycerols are the transport form of saturated (mono-unsaturated and trans-forms) fatty acids forming crystal phase. Phospolipids and cholesterol ethers are transport forms of polyunsaturated acids in the polar and crystal phases, respectively. Even in the forms of complex lipids saturated and polyunsaturated fatty acids are transported in the blood by various apoproteins. ApoB-48 transports saturated fatty acids to hepatocytes in the form of chilomicrons. ApoA-1 transports transports polyunsaturated fatty acids directly to cells including hepatocytes. ApoA-100 contains two lipid binding domains. It transports saturated fatty acids and their cholesterol ethers associated with the third and fifth domains, respectively. For the structural function polyunsaturated fatty acids are transported by ApoA-1 high density lipoproteins in the polar phase and they penetrate into cells via phospholipid re-esterification.     

Development of peripheral neurovascular disorders in miners exposed to cool microclimate

Complete clinical and physiologic examination of 415 tunnelers exposed to intensive vibration in cooling microclimate proved that extreme functioning of thermoregulation results in shorter development, quicker progression of vibration disease and abortive types of the disease. The data obtained were helpful to base treatments and prophylaxis including special clothes, appropriate therapy.     

Genotypic basis of low viability in vestigial mutants of Drosophila melanogaster

The role of a marker mutation and other genes in a decrease in viability was studied in the Drosophila melanogaster vg line. In flies of the C-S line, chromosome 2 was substituted by the homologous chromosome of the vg flies. In addition, the flies of the mutant phenotype with mutant genes partially or completely substituted by the wild-type C-S genes were obtained in saturating crosses C-S x vg. In the reciprocal variant of chromosome 2 substitution, the flies of the C-S phenotype with chromosomes 1, 3, and 4 from the vg line were obtained. Chromosome 2 of the vg line, introduced into C-S fly karyotype, proved to substantially reduce the heat resistance and life span of flies. In the case of reciprocal replacement (C-S line chromosome 2 substituted for the homologous chromosome of vg flies), a significant increase in viability was observed, which, however, never reached the level characteristic of the C-S line. As the vg genotype became saturated with C-S genes, the heat resistance and life span of flies increased substantially. However, even the complete saturation of mutant chromosomes with wild-type genes never resulted in the equal viability of vg and C-S flies. These data suggest that the low viability of the vg mutant is largely accounted for by the gene composition of the second chromosome and, primarily, by the presence of the vg gene. Nevertheless, there is evidence that, along with the pleiotropic effect of the marker mutation, other genes not linked to chromosome 2 are responsible for the studied physiological properties of the vg flies.     

Relaparotomy]

The study of intrarenal and upper urinary tracts urodynamics in the presence of the ureteropelvic obstruction and of the function of the lower urinary tract shows that congenital hydronephrosis was in 42.8% of cases associated with bladder dysfunction presenting with hyperreflex-type dysfunction. Maladapted hyperreflex bladder was diagnosed in 29.4%, adapted--in 13.5% of cases. The hyporeflex dysfunction occurred in 15.9% of cases. The urinary bladder dysfunction in children with congenital hydronephrosis accounts for 58.7%. These aggravate the same defects of the upper urinary tracts and deteriorate the course of chronic obstructive pyelonephritis.     

Causes and prevention of sudden arrest of circulation in surgical treatment of rheumatic mitral defect

Lymphangiomas are benign tumors, their growth are slow, customarily without symptoms, their location more frequent are in head or neck and they're diagnosed before the two first life years frequently. Their etiology continues uncertain, being accepted the congenital origin. We report on three cases of abdominal lymphangioma beginning as an acute abdomen. The importance of these cases is based mainly in the low frequency of presentation of these tumors in this location (2-5% of the lymphangiomas) and in their initial symptomatology.