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61.
J Bal D Maciejko E Bu?awa T Mazurczak 《Polski tygodnik lekarski (Warsaw, Poland : 1960)》1992,47(9-10):215-218
The results of DNA analysis with the aid of specific molecular probes are discussed. DNA analysis involved 22 families of a high risk of cystic fibrosis. A significance of the obtained results in genetic counselling is also discussed. DNA analysis enabled detection or exclusion of cystic fibrosis gene carrier state in patient's relatives. DNA analysis proved fully informative in case of 17 families being a base to offer these families prenatal diagnosis of the disease in the I trimester of pregnancy, if such a family plans conception, and to accept this diagnostic technique. 相似文献
62.
Jan Pałyga 《Biochemical genetics》1991,29(9-10):431-445
Histone H1 from erythrocytes of Japanese quail was resolved in a sodium dodecyl sulfate (SDS)-polyacrylamide gel into five fractions differing in apparent molecular weights. A polymorphism of histone H1.1, H1.2, and H1.3 bands was detected among quail individuals. While some birds possessed either a high (phenotype .3+) or a low (phenotype .3+/.3-) level of H1.3, at least half of the quail population lacked this H1 band (phenotype .3-). Appropriate genetic crosses demonstrated that H1.3 behaved as though it was coded by a gene with two codominant alleles at an autosomal locus. Using two-dimensional polyacrylamide gel electrophoresis (acid-urea followed by SDS gels), it was found that birds .3+ contained polypeptides H1.b1 and H1.b'1; birds .3-, polypeptides H1.b2 and H1.b'2 with lower apparent molecular weights; and birds .3+/.3-, both types of polypeptides in equal proportions. The H1.b2 + H1.b'2 complement was not discernible in SDS gels, for it migrated together with H1.c' within band H1.4. It was found that a small number of birds lacking the H1.2 band in SDS gels failed to express histone H1.a. Since birds with phenotype .2- with a defective allele of the gene H1.a were simultaneously lacking the H1.3 band, it seems that the imperfect allele of the H1.a gene might be closely linked to the alleles producing H1.b2 + H1.b'2. 相似文献
63.
A. B. Jarzębski J. J. Malinowski G. Goma P. Soucaille 《Bioprocess and biosystems engineering》1992,7(7):315-317
Simulations of continuous ethanol or acetonobutylic fermentations in aqueous two-phase systems show that at high substrate feed concentrations it is possible to obtain solvent productivities about 25–40% higher than in conventional systems with cell recycle if the biomass bleed rate is kept about one tenth of the value of D.List of Symbols
a
Volumetric fraction of dextran rich phase
-
B h–1
Bleed rate
-
D h–1
Dilution rate
-
P kg m–3
Product concentration
-
PD kg m–3 h–1
Productivity
-
S kg m–3
Substrate
-
X kg m–3
Biomass
-
Partition coefficient 相似文献
64.
65.
Lucyna Grębecka 《Protoplasma》1981,106(3-4):343-349
Summary Perforation of peripheral cell layers ofA. proteus in any place provokes immediate endoplasm efflux, what supports the view that the hydrostatic pressure is higher in the cell interior than outside. The local effusion of endoplasm results in the reversal of flow in formerly advancing pseudopodia, in agreement with the pressure gradient theories of protoplasmic streaming. Amoebae with destroyed frontal zones squeeze all their endoplasm out through the breach, what disproves the frontal contraction hypothesis of amoeboid movement, but supports the concept of a general contraction of cell cortex.Study supported by the Research Project II.1 of the Polish Academy of Science. 相似文献
66.
The effective synthesis of 4,4,14α-trimethyl-19 (10 → 9β) abeo-steroids (iv), (v), and (Vl) with two- and five-carbon side chains from lanosterol is described. Their structures were proved on the basis of spectral data. The title compounds are the first synthetic synthons for the preparation of 4,4,14α-trimethyl-steroids with an unnatural configuration. 相似文献
67.
A simple filter method for the fluorometric estimation of DNA in alkaline and neutral sucrose gradient fractions with DABA·2HCl is discussed. Alpha-450 membrane filters of regenerated cellulose (Gelman Instrument Co., Ann Arbor, Michigan) were used. In the proposed method washing of the DNA precipitate as well as the reaction with DABA·2HCl were performed directly on the filters, thus avoiding repeated washing and centrifugations of DNA precipitates applied hitherto in analogous fluorometric techniques. A good coincidence of the results concerning localization of DNA sedimentation profiles determined by radioisotopic and fluorometric methods was obtained. The method is very convenient for DNA estimation in alkaline and neutral sucrose density gradient fractions obtained by ultracentrifugation of DNA of nonproliferating cells where DNA labeling is very difficult, and in the case of human lymphocytes even impossible without stimulation for blastic transformation. Its other advantages are a considerably simplified procedure and a higher precision with respect to other fluorometric methods for determination of DNA. 相似文献
68.
Summary Normal mouse spleen cells take up in vitro radioactively labeled immune RNA. RNA taken up is present in nuclei, polysomes, membranes and cytoplasm. About 20–40% of immune RNA is nonspecifically associated with cell surface. 45% of RNA taken up is degraded and reutilized inside the cells within 2 hours.This work was supported by the Polish Academy of Sciences within the project 09.7.4.1.1. 相似文献
69.
70.
Examination was made of the effect of alternating light and darkness (LD 12:12) and constant light (LL) conditions on length of development and fecundity of the moth, Ephestia kuehniella. It was found the conditions applied cause acceleration of larval development on an average by 3 days in comparison with development under constant darkness conditions (DD). The fecundity of the insects examined decreases considerably under the experimental conditions.When pharate adults are kept in light for 18 hr per 24-hr period on the 6th to 7th day of their development, males incapable of fertilizing females are produced. 相似文献