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161.
F. PospíšiL 《Biologia Plantarum》1980,22(3):161-166
The influence of phenolic and humic acids on the activity of glucose-6-phosphate-dehydrogenase in the roots of pea under aseptic
conditions has been investigated. It seems clear that vanillic and protocatechuic acids inhibit the enzyme activity in the
excised roots of pea, but their dry weight increases in relation to the control. Gallic acid stimulates the G-6-PD activity
in the roots of whole plants. The humic acids influence neither the enzyme activity nor the dry weight of pea seedlings after
short-term treatment. 相似文献
162.
Dimethyl sulfoxide present in the agar medium at concentration 0.2 % (v/v) and lower does not inhibit cytokinin-induced betacyanin
synthesis in theAmaranthus caudatus seedlings. The activity of kinetin, N6-(Δ2-isopentenyl)adenine andtrans- zeatin is the same when these cytokinins are dissolved in either water or dimethyl sulfoxide and incorporated into the medium
after autoclaving. A simple method is described which allows the cytokinin activity of slightly water-soluble and thermolabile
compounds,e.g. aromatic urea and thiourea derivatives, to be determined in theAmaranthus bioassay. 相似文献
163.
Fractions of reticulocyte lysates were retained on heparin immobilized on Sepharose 4B and further separated by gel filtration on Sepharose 6B. These fractions contain aminoacyl-tRNA synthetases for 12 amino acids tested. Most synthetases with the highest specific activity are present in the fraction of approximately 40S. Particulate synthetases present in the postmicrosomal pellet of rat liver and synthetases associated with polyribosomes are almost completely adsorbed on heparin-Sepharose but free enzymes in the cytosol are not retained. Since only particulate synthetases are retained on the affinity carrier, their adsorbtion may be due to the presence of proteinsynthesis factors, in particular peptide initiation and elongation factors, in the complexes of synthetases. 相似文献
164.
Neonatal transplantation tolerance to the products of theH-2
b
complex was induced in B10.A (H-2
a
) mice. On the basis of the survival of skin allografts it was found that antigens determined by theD region of theH-2
b
complex (of the B10.A(2R) strain) were most easily overcome and that tolerance to the products of theD end of theH-2 complex (of the B10.A(4R) strain) was also easy to induce. The antigens produced by theK end ofH-2 (of the B10.A(5R) and B10.A(3R) strains) represented a stronger incompatibility barrier and a difference in the entireH-2
b
complex caused strongest resistance to tolerance induction. When tolerance to the products of the entireH-2
b
complex was induced in newborn B10.A mice, and the neonatally treated animals were grafted simultaneously with five different grafts, those disparate at theK end ofH-2 and in the entireH-2 region were rejected in some animals, while the grafts disparate at theD end of H-2 remained intact in the same mice. No dependence on theI-J subregion was observed in this system. Furthermore, tolerance was more easily inducible in male than in female B10.A mice. 相似文献
165.
Margareta Glanser Siniša N. Ban Charles L. Cooney 《Applied microbiology and biotechnology》1981,13(1):54-59
Summary In this work we discuss the aerobic biodegradation of sodium sulfite liquor of (NaSSL) and sodium lignosulfonate (NaLS) in
a firwood sulfite waste liquor by a mixed culture of microorganisms consisting of two Trichosporon yeasts and bacteria in the Arthrobacter (two species), Pseudomonas and Chromabacterium genera. Under established process parameters, the NaSSL was biodegradated in one or two stages by mixed cultures. The kinetics
in each stage was studied. The optimal ratio of NaLS and sugars in the substrate for the growth of mixed culture was determined.
The growth of the monocultures of the bacteria on the NaLS and the growth of the yeasts as monocultures on the NaSSL substrate
were examined. UV absorption and IR spectra were employed as analytical methods to follow the microbial degradation of NaLS.
The aim of this research was to study the biodegradation process and kinetics and to remove by means of mixed culture the
maximum amount of organic matter from NaSSL. 相似文献
166.
Summary Twenty-six yeast strains, representative of different yeast genera, were tested for their sensitivity to crude extracellular cellulolytic enzyme complexes obtained from the fungusTrichoderma reesei QM 9414 and its mutants M 6 and MHC 22 (Microcrystalline cellulose was the sole carbon source.) Practically all the yeast strains tested were found to be sensitive, exhibiting signs of cellwall weakening and lysis during prolonged incubation with the emzymes fromTrichoderma. Under growth conditions, the effect of cellulolytic enzymes on yeast cells and their growth rates was much less pronounced. However, at increased cellulase concentrations (5 mg/ml) in the growth medium, lysis of stationary phase yeast cells was observed. 相似文献
167.
Dr. I. Trebichavský M. Holub L. Jarošková L. Mandel F. Kovářů 《Cell and tissue research》1981,215(2):437-442
Summary The development of lymphoid populations in the omentum majus during the prenatal and postnatal life of the pig was studied. T lymphocytes, monocytes and mast cells were first found on the 40th day of gestation. B lymphocytes appeared on the 72nd day of gestation when the first macrophage aggregates were formed. Macrophages appeared to be the prerequisite for the formation of dense lymphatic areas (DLA's). At later stages T cells were observed only in the omentum of germfree pigs. DLA's of conventional pig omentum are filled exclusively with B cells. 相似文献
168.
169.
Summary Studies in 772 children and their mothers living in Porto Alegre, Brazil, disclosed three rare G-6-PD phenotypes. The first, observed in a dark mulatto, is probably identical to a variant previously found in Northeastern Brazil and was named Gd Minas Gerais-like; a white boy of German ancestry showed what seems to be Seattle-like; and a white man of Portuguese ancestry presented a previously undescribed variant that is being called Gd Porto Alegre. The allele responsible for Gd Minas Gerais may be more prevalent in Brazilian populations than was previously thought. Its estimated frequency in 214 black males from Porto Alegre is 0.005. 相似文献
170.
Thylakoid membranes of the cyanobacterium Plectonema boryanum solubilized with Triton X-100 can be resolved into three fractions of pigment-protein complexes (Hladík, J. and Sofrová, D. (1981) Photosynthetica 15, 490–503). Fraction I contained relatively the highest amount of carotenoids as well as monomeric forms of chlorophyll a, Fractions II and III contained chlorophyll-protein complexes with a characteristic exciton-split circular dichroism in the red region. It has been shown that fraction III is an oligomeric form of the chlorophyll-protein complex of fraction II. Circular dichroism spectra indicate that, different from fraction II, fraction III contains specifically oriented and space-fixed molecules of carotenoids. Thermal dissociation of fracion III to fraction II is accompanied by disappearance of the positive circular dichroism effect of carotenoids in the 500–550 nm region, thus causing deorganization of the carotenoids, proceeding in parallel to the geometrical rearrangement of chlorophyll molecules. Extraction of the carotenoids of fraction III with heptane is acompanied by dissociation of fraction III. We assume that the observed effects are due to binding of the two pigments to the protein component of the complex and that carotenoids can mediate a part of the interactions which stabilize the structure of pigment-protein complexes. Thus, besides the light-harvesting and protective functions, carotenoids can also play a structural role. 相似文献