当前位置: 首页 >> 检索结果
1641. [Genotypic differences in the level of N-acetyltransferase activity in mice of inbred lines and their hybrids].
There are "slow" and "rapid" acetylator phenotypes in mice according to N-acetyltransferase activity (E.C. 2.3.1.5) (N-AT). The results of direct, back- and reciprocal crosses of mice lines with rapid acetylation phenotype (C57BL/He) show monogenic autosomic control of acetylation locus (Ac) with rapid allele dominance and sex dependence upon N-AT activity in males. So, genetic polymorphism according to the Ac locus exists in mice as well as in some other animal species and in humans. The results obtained in this study demonstrated the correlation between the N-AT level in mice and their predisposition to malignant tumors as well as dependence of cyclophosphamide action on the N-AT activity upon the genotype of an individual, which suggests a certain role of the Ac locus in tumor development.
1642. [Familial myxomas of the heart].
作者: M A Nechaenko.;L P Cherepenin.;G F Sheremet'eva.;V A Makhovko.;M V Antonov.
来源: Klin Med (Mosk). 1991年69卷6期38-41页
An analysis has been made of the clinical, diagnostic, surgical and morphological aspects of familial cardiac myxomas, potentialities of their intravital diagnosis and prevention. No morphological differences were established between familial and sporadic cases of cardiac myxoma.
1643. [Induction of unstable mutations in Drosophila melanogaster by microinjection of oncogenic virus DNA into polar embryonic plasm. Malignant effect of oncoviral DNA].
We have demonstrated that the ability to induce benign neoplasms We have dominant mode of inheritance in Drosophila melanogaster is the specific feature of oncoviral DNAs. It is supposed that development of this type of neoplasms in Drosophila is connected with the changes in expression of protooncogenes in mutant genome: firstly, the genetic factors directing the development of neoplasms and Drosophila protooncogenes which shared the homology with v-src are localised in the same regions; secondly, there are structural rearrangements in c-src/fps (29A) protooncogene in mutant stocks which display the ability for neoplastic growth.
1644. [Genetic and environmental factors in the families of children with dystrophic bone cysts].
作者: M O Gudushauri.;E F Lordkipanidze.;L T Aladashvili.;I I Taboridze.
来源: Ortop Travmatol Protez. 1991年5期66-9页
On the basis of data of 49 probands' families with dystrophic osseous, cyst, 12 probands' families with giant cell tumor and 55 children from the general population by means of clinical and multidimensional-genetical analysis (cluster, discriminant) have been revealed genetical and environmental factors, contributing to the formation of the osseous cysts in children. There have been developed the directions of the search of the "principal" environmental and genetical factors, determined the qualitative criteria of the factor significance, revealed the structures of the mutual connection of the significant factors and obtained their prognostication value definition.
1645. [Proto-oncogene expression in the liver of male rats of different age].
作者: L B Novikov.;R M Balanskiĭ.;V N Anisimov.;K P Khanson.
来源: Biull Eksp Biol Med. 1991年111卷5期521-2页
The expression of 10 protooncogenes has been quantitatively studied in liver of male rats L10 age of 1, 10.5, 22 and 37 months. It was shown that a number of specific mRNA transcripts and, therefore, the levels of expression of protooncogenes C-MYC, C-FOS, N-MYC, HA-RAS, KI-RAS, SIS, ABL, YES, MOS and MET in rat liver were constant during life span. These data are in accordance with resistance of the rat strain L10 to spontaneous hepatocarcinogenesis.
1646. [Presence of specific mutation of Ha-ras oncogene in skin tumors of mice induced under different experimental conditions].
作者: A S Loktionov.;I G Popovich.;M A Zabezhinskiĭ.;V N Anisimov.
来源: Biull Eksp Biol Med. 1991年111卷4期398-400页
The mutation was revealed with substitution of A for T in the second position of the 61 Ha-ras oncogene codon in the DNA of 31 skin tumours (26 papillomas and 5 carcinomas) and in 23 mice treated with 12-O-tetradecanoyl phorbol-13-acetate (TPA). Part of these mice were F progeny (n-6) and F progeny (n-4) following DMBA administration during pregnancy, another part F progeny (n-5) following ENU action on males prior to mating, the rest mice (n-3) did not undergo additional actions. The mutation under study was revealed only in 3 out of 5 papillomas and in all 5 carcinomas of mice subjected to DMBA administration during pregnancy.
1647. [The DNA-mediated transformation of mouse fibroblasts after radiation damage to the cellular chromatin].
作者: V G Bezlepkin.;L B Ostrovskaia.;T A Bezlepkina.;A I Giaziev.
来源: Radiobiologiia. 1991年31卷2期188-94页
In experiments with NIH3T3 mouse fibroblast the authors showed a dose-dependent (gamma- or UV-radiation) increase in the immortalized fibroblast transformation by purified DNA preparations from Ehrlich ascites tumour cells. The transformant yield was the highest when the transfection started within the first few minutes after irradiation, when radiation lesions occurred in the genome and the system of enzymic DNA repair was activated. The proteolytic activity inhibition by treating the exposed cells with phenylmethanesultonyl fluorine reduced the radiation-induced transformation.
1648. [The behavior of the X chromosomes in intra- and interspecific hybrid cells of murine teratocarcinoma PCC4azal].
作者: N S Zhdanova.;S I Baĭborodin.;A Iu Kerkis.;L D Matiakhina.;O L Serov.
来源: Ontogenez. 1991年22卷2期158-67页
We have demonstrated that X chromosomes are reactivated in hybrids obtained by fusion of mouse PCC4azaI teratocarcinoma cells (XO, 39HPRT-) with splenocytes from mouse females heterozygous in Hprt gene. These hybrids are capable of spontaneous differentiation. We also obtained similar interspecies hybrids of PCC4azaI cells with bone marrow cells of the American mink. The majority of such hybrids remained undifferentiated, however, after long-term cultivation at high cell density they differentiated into epithelial- or fibroblast-like cells similarly to PCC4azaI cells. Two hybrids had the autosomal complement of the mouse and two X chromosomes (mouse and mink); both X chromosomes were active. These X chromosomes were not inactivated during differentiation in vitro.
1649. [The expression of P-glycoprotein in leukemia P388 cells with induced doxorubicin resistance].
作者: V A Sukhanov.;V L D'iakov.;V V Lalaev.;A V Iakh'iaev.;I M Voronkova.;F V Donenko.;N B Borovkova.;L V Moroz.
来源: Biull Eksp Biol Med. 1991年111卷3期290-1页
beta-D-galactose-containing glycoproteins were prepared from cells P-388 leukemia and from P-388 leukemia cells with induced resistance to doxorubicin. It was shown by HPLC method that plasma membranes from resistant cells contain 4-4.5% P-glycoproteins and plasma membranes from sensitive cells contain P-glycoproteins about 10 times lower.
1650. [New antineoplastic antibiotics, new analogs, modifiers of biological reactions and oncogene inhibitors].1651. [Characteristics of pathogenesis of acute leukemia in children].
The main components of acute leukemia pathogenesis have been considered from the current positions: origination of the leukemic clone, characteristics of leukemia tumor histogenesis, mechanisms of proliferation and differentiation of leukemic cells. The main pathogenetic differences of acute leukemia in children and adults have been traced. The importance of these differences for the clinical picture, prognosis and response to chemotherapy has been analyzed.
1652. [Prognostic factors in the development and course of acute lymphoblastic leukemia in children].1653. [The characteristics of the regulation of the cellular proliferation of embryonic rat fibroblasts transformed by E1A+c-Ha-ras oncogenes].
The ability of growth factors (GF) to stimulate proliferation of rat embryo fibroblast (REF) lines immortalized by E 1A oncogene and transformed by complementing E 1A and c-Ha-ras oncogenes (mutant form) was studied. Unlike untreated REF, those immortalized by E 1A oncogene required less serum and GF to proliferate. Proliferation could be stimulated by specific GF alone. Serum appeared to be capable of stimulating proliferation of cells transformed by E 1A + c-Ha-ras oncogenes; however, both GF and proteinases C and A activators failed to exert such effect. Transferrin, usually required by normal cells in late G1-phase, shared the stimulating effect on E 1A+c-Ha-ras-transformed cells. To summarize, E 1A+c-Ha-ras oncogene-transformed REF can grow independently of GF but still require transferrin.
1654. [Pharmacological correction of the cytogenetic effect of cyclophosphane].1655. [The medical genetic approach in the diagnosis of cancer].
作者: L V Akulenko.;V V Briuzgin.;I N Bazyma.;K I Zhordania.;E N Malygin.;A A Samgina.;M A Chekalova.;R F Gar'kavtseva.
来源: Vopr Onkol. 1991年37卷2期211-5页
Formation of registers of families afflicted by tumors of certain sites and dynamic follow-up of "healthy" members of such families is a new approach to early diagnosis and prevention of cancer. The results of a clinico-genetic study of hormone-dependent tumors of the female genitals and breast served as a basis for the development of a pattern of medico-genetic follow-up which, in turn, may facilitate integration of the above method with treatment for cancer of said and other sites.
1656. [The molecular mechanisms of the action of steroid hormones and the reasons for breast cancer resistance to hormonal therapy].1657. [Activation of the Ha-ras oncogene in tumors induced in mice by transplacental exposure to 7,12-dimethylbenz(a)anthracene].
作者: A S Loktionov.;M Hollstein.;N Martel.;D Galendo.;L Tomatis.;H Yamasaki.
来源: Vopr Onkol. 1991年37卷3期297-303页
A study of tumors induced in mice by transplacental exposure to 7,12-dimethylbenz(a)anthracene (DMBA) alone or in combination with postnatal tissue-specific promotion showed skin and liver tumor development to be associated with cellular Ha-ras oncogene activation in a large percentage of cases. As shown by Xba I RFLP, oncogene activation was caused by T for A substitution at the second position of codon 61. The said mutation was traced in DMBA-induced tumors of the liver alone but not in spontaneous hepatomas. The results of the study showed the role of oncogene activation in cancer development to be tissue-specific.
1659. [An increased frequency of allele A6 of the proto-oncogene HRAS1 in cancer patients].
Size and frequency of rare alleles of HRAS1 protooncogene were studied in 258 patients with various neoplasms and 32 healthy donors of the northwestern region of the USSR. Literature data on distribution of rare alleles of certain size in sick and healthy people were compared to our results. On the whole, 1918 HRAS1 alleles from cancer patients and 1104 alleles from donors were considered. The study established a significant increase in the frequency of rare A6 allele in cancer patients.
1660. [Multidrug resistance]. |