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1821. [Genetic and oncological characteristics of CC57BR/Mv mice].
The incidence of spontaneous malignancies in this line was 21.3% with predominance of haemoblastoses, adenomas of the lungs and liver. The study of the genetic character revealed homozygosis of mice CC57BR in all test genes.
1822. [Effect of lipid hydroperoxides on the yield of chromosome aberrations in irradiated cells].
The combined effect of linoleic acid hydroperoxide and gamma-radiation on Ehrlich ascites tumor cells was not additive with regard to the formation of chromosome aberrations. When cells were preincubated in the presence of a subliminal hydroperoxide dose of 2.10(-5) M the number of aberrant cells increased after irradiation.
1823. [Priorities in the directions of prevention of malignant tumors].1824. [Specificity of the interaction of carcinogenic and cytostatic agents with the elements of the genome at different levels of its organization].
The analysis of the literature permits drawing a conclusion that according to DNA binding site-specificity carcinogens and antitumour drugs can be divided into GC- and AT-binding compounds. When interacting with eucaryotic DNA such specificity leads to an increased binding of carcinogens and antitumour drugs to the repeat-rich DNA (satellite DNA, alpha-DNA, flanking regions of genes). It is supposed that specificity of the binding of chemical compounds on higher levels of genome organization (active and inactive chromatin, nuclear matrix-bound DNA) is also defined by the affinity of compounds to GC- or AT-rich repeats.
1825. [Role of carcinogenic factors in the external environment in the development of a hereditary predisposition to tumor growth (experimental data)].1826. [Tumor heterogeneity and the mechanisms of natural resistance in the metastatic process].
Data from literature concerning differences in cell populations between the primary and metastatic tumours are generalized. Their properties are considered as dependent on heterogeneity of the cell composition, karyotype, cell surface peculiarities and oncogene expression. The problem of the dependence of the ability of tumours to metastasize on their interaction with macrophages and natural killer cells is under discussion.
1827. [Amplification, rearrangement and expression of the c-myc and c-Ha-ras1 proto-oncogenes in patients with breast cancer].
The restriction analysis of breast cancer DNA revealed amplification of c-myc and c-Ha-ras oncogenes in 3 of 19 and 4 of 22 carcinomas, respectively. In two tumours containing amplified c-Ha-ras1-fragment an additional ras-band absent in unchanged lymphatic nodule and blood leukocytes of the same patients was revealed. Amplification of myc gene was registered in poorly differentiated carcinomas with high metastatic potential. c-Ha-ras1 activation (amplification and elevated expression) was identified in nonaggressive tumours with prolonged progression.
1828. [Pathogenesis of the tumor process].
The paper deals with fundamentals underlying current views on cancerogenesis, morphogenesis and tumor growth with special emphasis on the mechanisms of malignant sequential and spasmodic transformation of target cells, a morphologic pattern of malignant transformation (uni- and multicenter development, tumor field theories) and mechanisms of tumor dissemination. Recent conceptions and theories are delineated. Original ideas of the nature of neoplastic process are suggested.
1829. [2 phenotypic variants of B-cell lymphocytic leukemia].
A phenotype of lymphoid cells of peripheral blood in 38 patients with B-cel chronic lymphocytic leukaemia (B-CLL) was determined by means of a set of monoclonal antibodies. In the majority of the cases (32 persons--group I) the cells had an incomplete phenotype (CD 20+, CD 21-, CD 22-, CD 24+, CD 37+). In 6 patients (group II) cells had all the surface markers peculiar to B-CLL cells (phenotype--CD 20+, CD 21+, CD 22+, CD 24+, CD 37+). In 2 out of 6 cases lymphoid cells contained E-receptor (CD 2+). Cells of the patients from group I and II differed also in the level of TUI-receptor. An assumption is advanced about the existence of two phenotypic variants of B-CLL and about a possible association of CD 21 and CD 22 receptors.
1830. [Comparative evaluation of the antitumor, cytogenetic and immunodepressive effects of dimetinur when used perorally and parenterally].
作者: L A Osatrovskaia.;M M Fomina.;E P Bogoslovskaia.;S L Potapov.;D B Korman.
来源: Eksp Onkol. 1988年10卷6期44-8页
The dimethylnitrosourea action after oral and parenteral administration was comparatively evaluated on the basis of criteria for the antitumour and cytogenetic activity, as well as for the immune (T-cell) reactivity of tumour-bearing and intact animals. A considerable antitumour effect and the induction of the overload chromosomal aberrations in tumour cells with the complete preservation of bone marrow cells were observed during the oral drug application. Dimethyl nitrosourea-induced T-cell depression in murine spleen was transitory and reversible. Thus the oral administration of the drug was shown to be optimal for realization of its therapeutical activity with the least toxic side effect on the host normal hemopoietic and immunocompetent cells.
1831. [Traditional and nontraditional approaches to studies of HLA association with diseases].
作者: E A Zotikov.;R M Kut'ina.;N A Krasnikova.;A I Udovichenko.;L S Liubimova.
来源: Vestn Akad Med Nauk SSSR. 1988年7期43-7页 1832. [Action of khanerol on the superhelical DNA structure of S-37 cells].
The damaging effects on the structure of a supramolecular DNA complex of sarcoma-37 cells in mice following the use of the therapeutic doses of khanerol were found. Capillary elastoviscosimetry and nucleoid sedimentation procedure showed that the damage of the supramolecular DNA complex structure becomes apparent already after 4 hours, and increases by 24 hour. In studies of the binding of khanerol with DNA by Cd and Tmelt. the procedure showed direct interaction of khanerol with DNA. The role of conformational changes of the supramolecular DNA complex in the cytotoxic action of antitumour agents is discussed.
1833. [Tumors in transgenic mice].
Transgenic mice are a suitable model for studying problems of modern biology on the molecular, cellular, and tissue levels. It is shown that some transgenic mice with integrated c-myc, v-myc, T-ag SV40, BPV have spontaneous tumours and may be used to study the role of oncogenes in the tumour development.
1834. [Clinico-epidemiological significance of environmental carcinogenic factors in the emergence of a hereditary disposition to tumor growth].1835. [Modern approaches to the molecular diagnosis of leukemia].
New outlooks in the diagnosis of leukemia and lymphomas with using recombinant DNA technology are reported. Possibility of DNA and RNA analysis to detect specific gene markers are demonstrated. It is a new tool for the precise identification of malignant clones of hematopoietic cells and for the improvement of early diagnosis.
1836. [Gene amplification and rearrangement of murine ribosomal RNA in virus-induced Rauscher leukemia].
作者: D A Domninskiĭ.;E S Pokrovskaia.;I A Smirnova.;Z A Butenko.;N I Grineva.
来源: Eksp Onkol. 1988年10卷6期17-21页
Using as a hybridization probe cDNA 35s RNA from the Rauscher leukemia cells, a part of rRNA gene cluster from the gene library of mice C-1 erythroleukemia cells has been cloned. Fragment 6.7 kb recloned into pUC19 rRNA was used as a probe to analyse organization of rRNA genes of mice with RL. The observed amplification and rearrangement in genome DNA of spleen cells are determined by a new type of their rRNA genes rearrangement in the nontranscribed as well as in the transcribed part of rRNA.
1837. [Hepatitis B virus and the development of human embryonal tumors].
作者: A K Naumova.;E N Sotnikova.;V V Tsibinogin.;V I Korenev.;A F Bukhny.
来源: Mol Biol (Mosk). 1988年22卷1期106-10页
Sera from children bearing embryonal tumors and from their parents were screened for the presence of hepatitis B virus (HBV) and its DNA by means of serology and molecular hybridization, respectively. Sera from tumor-bearing children and their parents both contain HBV or its DNA at average 5 times more frequently than the healthy donors or patients with non-oncological diseases. It is suggested that the presence of HBV or its DNA is caused not solely by infection during cure but also by vertical transmission from parents. The presence of HBV or its DNA might be treated as a risk factor increasing the development of embryonal tumors.
1838. [Differential expression of 2 genes of the Na+,K+-AtPase subunit in normal and tumor tissues in humans].
作者: E D Sverdlov.;K E Petrukhin.;N S Akop'iants.;N E Broude.;G S Monastyrskaia.
来源: Dokl Akad Nauk SSSR. 1988年298卷1期236-9页 1839. [An inhibitor of translation in cellular mRNA containing the 100S structure from Krebs II ascites carcinoma cells infected with encephalomyocarditis virus].
As shown previously, the bulk of cellular mRNA in Krebs II ascite carcinoma cells infected with encephalomyocarditis virus during active virus-specific synthesis is bound to ribosomes within the 100S structure which is inactive in protein synthesis. In order to elucidate the reasons for the translation repression of cellular mRNA within the 100S structure, a fraction of loosely bound proteins which are liberated by treatment of the 100S structure with 0.5 M KCl an which contain sum translation factors, was obtained. This fraction was shown to contain an inhibitor which non-specifically represses the translation of endogenous viral and cellular mRNA within the composition of polyribosomes and of exogenous poly(A)-containing cellular mRNAs from ascite carcinoma cells.
1840. [Proto-oncogene expression in mouse leukemia induced by the Mazurenko virus].
作者: N N Mazurenko.;N B Seniuta.;T I Gladkova.;N P Mazurenko.
来源: Biull Eksp Biol Med. 1988年105卷1期71-4页
The expression of 8 protooncogenes was examined in different types of murine leukemia induced by Mazurenko virus. C-myc-specific RNA (2, 3 kb and 1.8 kb) was revealed only in tissues of mice with thymomas (T-cell leukemias) but not with generalized leukemias. 1.4 kb Ha-ras RNA transcripts were observed in all RNA species from leukemic mice. The highest expression of the above oncogenes was noted in thymus and lymph nodes, in spleen and liver the expression was lower. Ki-ras, abl, fos, myb, erb and B-lym-specific RNA expression was not observed in any of the tissues tested. The expression of C-myc RNA is believed to be the result of C-myc activation due to provirus integration.
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