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191.
The effect of soluble glucan derivates on spleen colony-forming units in sublethally irradiated mice
A. Líšková J. Wagnerová L. Červeňáková A. Krištofová M. Ferenčík 《Folia microbiologica》1990,35(4):353-362
We examined the effects of 5 soluble derivatives of yeast glucan on the formation of exogenous (CFU-S) and endogenous (E-CFU)
colony-forming units in the spleens of sublethally irradiated (60Co, 6.5–7.0 Gy) mice of two inbred strains. For the estimation of CFU-S, glucans were administered intravenously either to
donors or recipients of spleen cells 24 h prior to irradiation or removal of the spleen. The number of CFU-S was increased
when both the donors and recipients were treated with glucan; the highest increase was obtained with glucans S, P and K. All
glucan preparations increased significantly also the number of E-CFU even when administered 90 min after irradiation. There
exist differences in the response to the stimulatory effect of glucans among individual mouse strains. Thus, for example,
the stimulatory effect of glucan KM on the E-CFU number was significantly more pronounced in strain A/Ph than in strain C57B1/6. 相似文献
192.
A method, suitable for the isolation of closed circular plasmid DNA from methylotrophic bacteria is described. Improvement
of cell lysis was achieved by butanol extraction of cells before application of the lytic agent. Using this method, cryptic
plasmids of 7.8, 14, 36 and 200 kb were purified from soil-isolated methylotrophs. 相似文献
193.
A transient 7-fold rise of ppGpp concentration, 2-3-fold increase of pppGpp concentration and 50 % drop of the concentration
of GTP inBacillus megaterium cells immediately after their transfer to the sporulation medium were observed. Actinomycin D, in concentrations inhibiting
RNA synthesis by 95%, blocked the rise of the (p)ppGpp pool and caused an instant several-fold increase of the GTP level.
When the cells were exposed to actinomycin D in the sporulation medium for a 1-h period (time 0–1 h, 1–2 h or 2.20–3.20-h),
they were able to form colonies on nutrient agar after being kept, in addition for 1–2 h in the sporulation medium free of
the antibiotic. The ability of sporulation was, however, markedly limited. The share of cells that could sporulate increased
when the irreversible sporulation phase was reached. 相似文献
194.
J. Matoušek P. Dědič M. J. Beneš P. Kopáček Věra Turková Ludmila Trněná 《Biologia Plantarum》1990,32(6):460-473
A polyspecific antiserum against protein extracted from PSTV-infected tomato leaves was prepared and the IgGs were separated
by affinity chromatography on a beaded cellulose adsorbent with an immobilized “healthy” antigen. The antibody not adsorbed
entered into a preferential reaction with the antigen from PSTV-infected leaves as estimated by an enzyme-linked immunosorbent
assay. The immunochemical reactions did not significantly exceed the control background, if antigens from tomato leaves infected
with potato viruses X, Y and M were analyzed. By immunoblot technique we revealed, however, that several antigens not detected
in healthy leaves appeared in the leaves infected either with PSTV or with viruses X and M. An accumulation of a major antigen
having a molecular mass of about 70 kDa was observed in viroid-infected leaves only, suggesting the specificity for viroid
infection. The antigen was found not to be an alkaline endoproteinase - the pathogenesis-related protein P-69.
Some antigens with molecular masses approximately 38.0, 23.7 and 22 kDa, which occurred in PSTV-infected leaves and in healthy
calluses, were not detectable in PSTV-infected calluses.
No reaction exceeding the control level was observed using enzyme-linked immunosorbent assay for antigens from silver nitrate-treated
tomato leaves, although such leaves showed symptoms similar to that caused by viroids. 相似文献
195.
Deletion of 13q in two patients with retinoblastoma,one probably due to 13q- mosaicism in the mother
Summary We examined the peripheral blood chromosomes of eight patients with retinoblastoma. In two of them an interstitial deletion of 13q was found. The breakpoints were determined as follows: case 1, 13q1221; case 2, 13q1231. In both cases, band 13q14 was deleted. In case 2 the lymphocytes of the mother showed the identical interstitial 13q deletion in 3 of 100 mitoses, thus raising the possibility of maternal origin of the 13q deletion in a child. In one patient, retinoblastoma was unilateral; in the other, bilateral. Both patients were mentally retarded. 相似文献
196.
197.
Phosphatidylcholine is one of the most frequent phospholipid components of the inner mitochondrial membrane ofNeurospora crassa. Quantitative analysis of phospholipids of the wild strain ofNeurospora crassa and of its twocho mutants showed that these strains did not significantly differ in the content of phosphatidylcholine. Mutants cultivated
in a medium without choline contained, as compared with the wild strain, an increased amount of phosphatidylserine and a decreased
quantity of phosphatidic acid. Respiratory activity increased and sensitivity to inhibitors of respiration changed. It is
likely that the presence of choline in the growth medium exerts a regulatory effect on the cell metabolism of these mutants. 相似文献
198.
This communication describes a new savanna-like community, theBletio purpureae-Andropogonetum gracilis Balátová-Tulá?ková etR. Capote ass. nov., found in the woodless eastern part of the Sierra del Rosario Mountains (western part of Cuba). From the phytosociological point of view, it belongs to the allianceAchlaenion piptostachyae Balátová-Tulá?ková all. nov., the orderAchlaenetalia piptostachyae Balátová-Tulá?ková ord. nov., and the classSclerio baldwinii-Andropogonetea gracilis Balátová-Tulá?ková cl. nov. In the area under study four subassociations were distinguished: theBletio-Andropogonetum typicum Balátová-Tulá?ková et.R. Capote subass. nov., theB.-A. rhynchosporetosum fascicularis Balátová-Tulá?ková etR. Capote subass. nov., theB.-A. cassietosum aeschynomenes Balátová-Tulá?ková etR. Capote subass. nov., and theB.-A. stenandrietosum droseroidis Balátová-Tulá?ková etR. Capote subass. nov. 相似文献
199.
200.
Dagmar Jičínská Eduard Brabec Marcel Rejmánek Jan Jeník Joří Haager Josef Holub Věroslav Samek Hana Rambousková Josef Holub Marie Naděžda Končalová Robert Neuhäusl Josev Kyncl František Krahuleo Jaroslav Dobrý Blanka Úlehlová Jiří Úlehla Eliška Rybníčková Kamil Rybníček 《Folia Geobotanica》1982,17(4):431-448