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991.
SV Slonitski? AA Maevski? VB Mantulenko EV Frisman 《Canadian Metallurgical Quarterly》1980,14(4):754-758
The influence of acetamide (AA) on the native DNA molecule conformation has been studied by methods of flow birefringence and viscometry. On one hand, it was shown that hydrodynamical and optical behaviour of the macromolecule at extremely low additions of AA is qualitatively the same as in the presence of nonelectrolytes which stabilize the water structure. On the other hand, the influence of intermediate and large AA concentrations on the native DNA molecule conformation is qualitatively the same as of corresponding urea concentrations, which is known to be a structure-breaker. The influence of AA on the thermostability of the native DNA molecule as well as on the stacking-association constant of adenosine has been studied by a spectrophotometric method. The obtained data confirm the hypothesis of the importance of ion-dipole interactions between nonelectrolytes and the phosphate groups of the DNA molecule. 相似文献
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993.
EK Balashova DL Pevzner VI Rozengart OE Sherstobitov AA Abduvarkhabov 《Canadian Metallurgical Quarterly》1976,48(4):460-464
Hydrophobity (coefficient in distribution in the hexane water system) and the content of cholinesterase organophosphorous inhibitors (OPI) of the structure Ro (CH3) P (O) SC2H4 SC2H5 were studied in the rat brain. When the O-alkyl radical is increased hydrophobity rises and the relative content of free OPI in the brain extracted by chloroform decreases. With an increase in R from the ethyl to butyl one the ability to the additional inhibition of the brain own cholinesterase lowers due to incubation of homogenate at 37 degrees C, that evidences for an essential drop in the studied series of the free OPI fraction relative to the free OPI extracted by chloroform. 相似文献
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998.
AA Khokhlov 《Canadian Metallurgical Quarterly》1976,2(2):98-99
A case of chronic prostatitis where conventional chemotherapy and repeated transurethral resections failed to relieve pain is described. A cutaneous uretero-entero anastomosis was performed for troublesome pain and incontinence and only a permanent sympathetic block with phenol at the level of L4 achieved complete pain relief. 相似文献
999.
Following an episode of rheumatic carditis, severe mitral incompetence developed in a 9-year-old girl. A mitral annuloplasty succeeded for a short time in ameliorating her symptoms of cardiac failure. However, mitral incompetence recurred and was accompanied by severe anemia and hemosiderinuria. Distortion of erythrocytes was evident on a peripheral blood smear. A second mitral annuloplasty resulted in resolution of the hemolytic anemia. 相似文献
1000.
AA Hartmann 《Canadian Metallurgical Quarterly》1978,263(1):105-114
The behaviour of the aerobic skin flora of the flexor sides of the forearms, under a three-week restriction of washing, was investigated in twenty-four patients for its quantitative and qualitative aspects. The combined scrabbing-washing method was used as described by Burtenshaw with Ringer's solution. After a three-week restriction of washing, using the Wilcoxon-Test, statistically no significant changes in the total number of microorganisms were found in areas investigated in the intermittent sampling of the skin flora. A three-week restriction of washing in the region of the flexor sides of the forearms does not induce significant changes in the composition of the normal aerobic skin flora. The percentage of differences in the total number of bacteria fluctuates up to the mark in wide limits; statements about standard deviations are not permitted because of the technical and experimental conditions. There was no shifting of the Resident flora to other groups of bacteria in the patients under study. Pathogenic microorganisms could not be found in higher numbers after the second sampling. 相似文献