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101.
V. Chaloupecký 《Folia microbiologica》1964,9(4):232-237
- 1.It was found that growing cells always contained more different groups of ribosomes and their total amount was greater than in non-growing cells or spores, in which only two ribosome groups with different sedimentation constants, according to the species of microorganism, were consistently found. 相似文献
102.
Summary A study of enzymatic equipment of enterochromaffine cells (e.c.) in jenual biopsies obtained with a Crosby capsule in normal humans and patients with nontropical sprue was undertaken. The following enzymes were demonstrated: alkaline phosphatase and adenosine triphosphatase (cell membrane), acid phosphatase (corpuscular), non-specific esterase (diffuse and corpuscular, predominantly eserine resistant, in corpuscular localization E 600 resistant), DPN- and TPN-diaphorases and dehydrogenases of lactic acid, malic acid, isocitric acid, glucoso-6-phosphoric acid, succinic acid, -hydroxybutyric acid and -glycerophosphoric acid. Enzyme activities were not equal in all cells suggesting some type of secretory cycle. In most patients with untreated nontropical sprue or with the disease in relapse e.c. were more numerous and hypertrophic with elevated activities of non-specific esterase and acid phosphatase. Implications of these results are briefly discussed.With 8 Figures in the Text, of which 2 in Colour 相似文献
103.
Ve snaze identifikovat fyziologické pochody rozhodující o selektivní toxicitě pyrazonu (1-fenyl-4-amino-5-chorpyridazon-6) jsme sledovali jeho vliv na hlavní enzymové systémy ?ídící dýchání ko?en?. Zatímco jsme u ko?en? zeSinapis alba zjistili úplnou inaktivaci dehydrogenázy kyseliny jantarové—u ko?en? cukrovky je stejný enzym stimulován. 相似文献
104.
A simple biochemical procedure was obtained for studying metabolism ofCorynebacterium diphtheriae during submerged cultivation based on the modification of the assay of dehydrogenase activity using 2,3,5-triphenyltetrazolium
chloride as redox indicator. Results obtained by the estimation of the dehydrogenase activity using TTC are in a good accordance
with oxygen consumption assayed manometrically. By following dehydrogenase activity in submerged cultivations of a production
strain ofCorynebacterium diphtheriae PW8-Weissensee we found that a massive toxin production is connected with the decrease of the activity of cells. This fall
of activity occurs yet during the exponential phase of growth. Especially a sudden fall of succindehydrogenase activity exactly
indicates the beginning of a considerable toxin accumulation in the medium. The presence of inhibitory concentrations of iron
ions in the medium not only increases the level of dehydrogenase activity but changes its whole kinetics. A retarded and irregular
fall of the activity occurs instead of a sharp one typical for good toxin production. 相似文献
105.
Changes in the radioresistance of bacteria after the inhibition of proteosynthesis in the preirradiation phase 总被引:2,自引:1,他引:1
The strain ofEscherichia coli WP2 (tryv) was irradiated with UV light, at a dosage of 240 erg/mm. Proteosynthesis was inhibited by the elimination of the essential
amino acid from the cultivation medium. Changes in radioresistance were followed during 45 minutes of starvation and during
the subsequent 45 minutes of restitution after the addition of the essential amino acid. The radioresistance of the cells
showed a linear increase immediately after the removal of the essential amino acids, proportional to the duration of the inhibition
of proteosynthesis. The increase in radioresistance was shown to be reversible. After the addition of the essential amino
acid there was an immediate decrease in radioresistance which was most marked in the first 15 minutes. 相似文献
106.
The existence of six amylase heterogeneity variants in serum and urine has been discovered in a group of 111 families with twins, and the frequence of each variant was determined. It had been shown that each of these amylase heterogeneity variants is inherited codominantly, and the mode of inheritance is demonstrated schematically.These amylase heterogeneity variants may be used as an aid to twin zygosity determination and also in paternity problems. 相似文献
107.
From the results obtained in the present work it is concluded that gamma globulin of the 7 S type (γG) which represents the main immunoglobulin component of pig colostrum, differs from serum γG globulin by the presence of another type of polypeptide chain, designed L2; the latter was detected after S-sulfonation in starch gel electrophoresis as the fastest moving component and its immunoelectrophoretic pattern shows the presence of two precipitating components. Preparation of soluble heavy and light chains enabled us to study them imunochemically. The heavy chain is represented by two zones; the fainter one was not detected in comparative analysis of the heavy chain of serum γG globulin. The L1 chain of colostral gamma globulin and the light chain of serum gamma globulin seem to contain three precipitating components, one of which appears due to aging of the chain solution in the presence of glycine. The material from colostrum seems to contain a larger amount of this component than serum. Further it was shown that the component arising in this way is antigenically closely related to the heavy chain. 相似文献
108.
R. Řetovský 《Folia microbiologica》1965,10(4):230-235
Colour tests for study of the nuclear apparatus ofChlorella cells are described. It can be concluded from the results thatChlorella cell nucleus contains a relatively large nucleolus; the peripheral layers of the nucleus are rich in chromatin only in the nuclear division phase. The nucleus divides by a simplified form of mitosis, characterized morphologically by simple constriction. 相似文献
109.
110.
The work is concerned with the question of the effect of humic acids on the biological action of agropyrene, the effective substance from the rootstock of Agropyron repens (L.) P. BEAUV. The test organism was the alga Scenedesmus obliquus (TURP.) KRÜGER, cultivated in mineral solution. The basic biological test was the determination of the number and size of the cells of this alga. It was found that the way in which agropyrene acts on combined application with humus acids depends on which humus fraction is used. It can display a synergic action if humic acid is used, since this substance probably facilitates the penetration of agropyrene into the cells. On the other hand, fulvic acid counteracts the activity of agropyrene and this most probably by mutual binding and blocking of active groups and links. 相似文献