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Results 451 - 500 of 524
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Kurnit D M - - 1984
A search for genes located on human chromosome 21 resulted in the isolation of a HeLa cDNA clone, pUNC724, which hybridized to 3.7 and 2.5 kilobase (kb) EcoRI fragments on each of the human acrocentric chromosomes. In situ hybridization further localized pUNC724 to the pericentromeric region of the human acrocentrics. ...
Schmid M - - 1984
Three cases of inherited satellited Y chromosomes (Yqs) were analysed using several cytogenetic techniques. The cytogenetic data of the 14 cases of Yqs chromosomes described to date were reviewed. All Yqs chromosomes carry an active nucleolus organizer region (NOR) in their long arm and must have developed from translocations involving ...
Collard J G - - 1984
Human chromosomes were separated on basis of size by velocity sedimentation at 52g in a specially designed sedimentation chamber. The chamber has been constructed in such a way that large numbers of chromosomes can be fractionated on a sucrose gradient while wall sedimentation, streaming, and swirling movements of the gradient ...
Langer G - - 1984
Specific recombinant DNA sequences (5S rRNA, B1, albumin) were assigned to flow sorted chromosomes of the Chinese hamster cell line CHV79. For this purpose, a rapid protocol was developed using filterbound chromosomal DNA and probing with various nucleic acids, that allows sequence identification in chromosomes. A flow histogram and a ...
Bernheim A - - 1983
A method is described for directly hybridizing a small number of sorted chromosomes with specific DNA probes. The chromosomes are analyzed by flow cytometry and sorted by deflecting the droplets containing the desired chromosomes onto a nitrocellulose filter. By using probes specific for the human Y chromosome, it has been ...
Bayless-Underwood L - - 1983
Accurate interpretation of chromosomal variants is essential in prenatal diagnosis in order to distinguish polymorphisms from potential pathology in the fetus. This paper reports intra-uterine diagnosis of a satellited Yq in two unrelated families. The 29-year-old consultant in Case A sought prenatal diagnosis because of a maternal family history of ...
Vogt P - - 1983
Six recombinant DNA clones are described, which are derived from the Y chromosome of Drosophila hydei. They reveal characteristic features of Y chromosomal DNA sequences. Three of the cloned inserts are Y-specific and are members of the same family of repeated sequences associated with the lampbrush loop-forming fertility gene "nooses" ...
Verma R S - - 1983
The frequency of different types of satellite associations of nucleolar organizing human chromosomes (i.e. acrocentric chromosomes; 13, 14, 15, 21, and 22) is reported using 10 normal individuals by Ag-staining technique. The preferential involvement of acrocentric chromosomes in satellite association is suggested. Only acrocentric chromosomes with active NORs (i.e. Ag-stained) ...
Musilová J - - 1983
5'-Bromodeoxyuridine (BrdU) present in the course of late S and G2 phases of the cell cycle in PHA-stimulated human lymphocyte cultures causes the despiralization and elongation of some chromosome regions, including short arms of acrocentric chromosomes. BrdU present at a concentration of 250 microM during the last 10 h in ...
Raczkiewicz B - - 1983
Chromosome studies in married couples were performed in order to elucidate their infertility, spontaneous abortions and foetal wastage. Peripheral blood lymphocyte metaphases of 311 persons revealed chromosomal abnormalities in 26 married people. Chromosome aberrations found here were distributed among sex chromosome aneuploidy (complete and mosaic form), structural anomalies of the ...
Di Lernia R - - 1982
Satellite associations were used as parameters to test nucleolar organizer activity. Assuming that toxic and/or mutagenic agents may affect the ribosomal genes, satellite associations in human lymphocytes were analysed following exposure to X-rays and compared with the satellite association pattern of subjects exposed to TCDD. A significant decrease in the ...
Varella-Garcia M - - 1982
Lymphocyte chromosome preparations from 51 malformed patients with idiopathic mental retardation were analyzed for presence or absence of prominent satellites, a high frequency (22%) of s+ variants being found. However, it is not possible to visualize a phenotypic tendency in the s+ patients either as an increase or decrease in ...
Ranganath H A - - 1982
The DNA from the two Drosophila nasuta races, D. n. nasuta and D. n. albomicana was investigated by CsCl density gradient centrifugation. D. n. nasuta has one major AT-rich satellite DNA sequence with a density of 1.664 g/cm3, while D. n. albomicana has at least three satellites with densities of ...
Kuhn E M - - 1982
We have collected 23 sporadic symmetrical triradial chromosomes (plus one D with duplicate satellites), 22 from cultured lymphocytes and one from a bone marrow cell. Fifteen triradials were from patients with Bloom's syndrome, and two from a Fanconi's anemia patient. The following chromosomes and chromosome groups were involved: 1, 2, ...
Lebo R V - - 1982
We have determined the subchromosomal location of the human insulin gene by analyzing DNA isolated from sorted human metaphase chromosomes. Metaphase chromosome suspensions were sorted into fractions according to relative Hoechst fluorescence intensity by the fluorescence activated chromosome sorter. The chromosomal DNA in each fraction was characterized by restriction endonuclease ...
Diaz M O - - 1981
We have isolated genomic DNA clones from the newt Notophthalmus which contain one or more copies of a 222 bp tandemly repeated sequence (satellite 1). Satellite 1 occurs in the pericentromeric heterochromatin of all chromosomes and at the sphere loci of chromosomes 2 and 6. Lampbrush chromosome loops associated with ...
Spurná V - - 1981
The population of DATURA STRAMONIUM L. var. TATULA T ORR and DATURA WRIGHTII R EGEL was heterogenous in the numerical and structural composition of karyotypes. DATURA WRIGHTII R EGEL contained, as well as aneuploid sets, a 35% karyotype with a diploid set of chromosomes (2n = 24); there were no ...
Venolia L - - 1981
The major satellite of M. r. robustus DNA has been isolated in a Ag+-Cs2SO4 gradient. It has a density of 1.710 g/cm(3) compared with 1.697 g/cm(3) for the bulk of the DNA, and accounts for about 10% of the total DNA. Sequence heterogeneity within the satellite was shown by an ...
Imaizumi K - - 1981
A seven-year-old Japanese girl with mental retardation, epileptic seizures controllable by anticonvulsants, short stature, and multiple minor malformations was found to have apparent giant satellites on chromosome No.13. The karyotypes of her parents and elder brother were normal. Banding studies revealed that the apparent giant satellites consist of four G-bands, ...
Chen T R - - 1981
We found eight polymorphic variants in human chromosome 15 using Q, C, Q-C and Ag-NOR staining methods. These variants included brightly or dully fluorescent pericentric segments and satellites, giant satellites, increased amounts of short arm hetrochromatin (ph+) and darkly (C band-positive) or lightly (C band-negative) Giemsa-stained pericentric Q-negative segments. These ...
Gosden J R - - 1981
A sequence derived by ECoRI restriction of human satellite DNA III has been cloned in lambda gt WES. The cloned DNA was used as a template for in vitro synthesis of cRNA, which was hybridized in situ to preparations of human metaphase chromosomes with a range of heterochromatic polymorphisms. Most ...
Steffensen D M - - 1981
In situ hybridization using 3H-RNA probes has been used to localize the sequences found in two satellites of density 1.705 g/cc and 1.672 g/cc to specific sites within the chromosomal complement. A detailed analysis of the sites on the S chromosome was carried out using the acute series of inversions ...
Amos A - - 1981
Several species of tsetse fly within the Morsitans and Fusca subgenera of Glossina contain supernumerary (B) chromosomes. Previous studies on the meiotic behaviour of chromosomes (Southern and Pell, 1973) and the C-band patterns (Jordan et al., 1977) have indicated a close similarity between the Y chromosome and the supernumeraries. The ...
Yip M Y - - 1981
Chromosomally normal and trisomy-21 individuals were studied for the ability of their nucleolus-organising chromosomes to form satellite associations in G-banded lymphocyte metaphases. Two types of parameter, absolute association frequency and relative association frequency, were used. There was no significant difference between females and males or between Caucasoids and Mongoloids for ...
Beek B - - 1981
Satellite associations were analysed in differentially stained human leukocyte chromosomes, obtained from four patients with Down's syndrome and four normal probands. A particular type of close association between two acrocentrics, showing a non-random arrangement of sister chromatids in a concordant dark-to-dark and light-to-light alignment, was found to be more common ...
Niikawa N - - 1980
A 2-month-old female infant with typical features of the 13q-syndrome was found to be a hitherto unreported mosaic consisting of 46,XX,del(13)(q22)-46,XX,r(13)(p13q22). Both of the 13q- and r(13) chromosomes were Ag N banding positive. Therefore, it was assumed that they had retained the satellite stalks. Two possible mechanisms were proposed for ...
Stella M - - 1980
A Y chromosome with satellites at the end of the long arm is reported. The banding techniques RBG, GTC, C and N were used. C-banding revealed a reduction of the heterochromatic part of the chromosome. The pedigree of the family didn't show any pathological feature in the carriers of this ...
Brown S D - - 1980
DNA was isolated from a chinese hamster/mouse hybrid cell line containing a single mouse chromosome, the X-chromosome, and digested with a variety of restriction endonucleases known to cut mouse satellite DNA. After agarose gel electrophoresis and transfer to nitrocellulose, hybridisation was carried out to a radioactive mouse satellite DNA probe. ...
Di Lernia R - - 1980
Satellite associations and silver staining were analyzed in a normal woman carrying three "s" variants, on chromosomes 13, 21, and 22. Six of the acrocentric chromosomes were identified and a positive correlation between the parameters of satellite association frequency and positive silver staining was found for each chromosome. These parameters ...
Yu C W - - 1980
The finding of heteromorphisms in certain regions of human chromosomes is useful in chromosome identification, especially in the study of the origin of nondisjunction. Quantitation of heteromorphisms in the smaller human chromosomes is theoretically valuable but remains technically difficult. In this paper we evaluate two methods for quantitation of human ...
Balícek P - - 1980
Fifteen unrelated individuals were found among the patients of the Cytogenetics Laboratory who possessed multiple-satellited marker chromosomes (14 with double satellites and 1 with triple satellites). Cytogenetic analysis was carried out by means of a conventional staining method and also by R, C, and Q banding and by the technique ...
Singh L - - 1980
Satellites visible in female but not in male DNA were isolated from the snakes Elaphe radiata (satellite IV, p = 1.708 g x cm-3) and Bungarus fasciatus (BK1 minor, p = 1.709 g x cm-3). The satellites cross hybridize. Hybridization of 3H labelled nick translated BK minor satellite DNA with ...
Miklos G L - - 1980
When differences are found between related species of organisms, it is often assumed that the differences themselves are causal factors either in speciation itself or in processes related to speciation. Two recent proposals on the functions of satellite DNA (Hatch et al., 1976 and Fry and Salser 1977) are that ...
Wegner R D - - 1980
Disomic and trisomic cells of a patient with Down syndrome mosaic were used to study the effect of the additional chromosome 21 against an identical genetic background. The frequency of AG staining and the participation in satellite associations were determined for each pair of acrocentric chromosomes. The additional chromosome 21 ...
Bartsch H D - - 1980
The possible derivation of a small supernumerary marker chromosome was investigated by means of different staining techniques and the frequency of satellite associations. It could be demonstrated that the marker chromosome participates at satellite association more than randomly. The marker chromosome is supposed to derive from 2 of chromosomes 13, ...
Duhamel-Maestracci N - - 1979
The in situ hybridization method has been used to investigate the localization of each of the three satellite DNAs present in the genome of the guinea pig. Purified fractions of the satellite DNAs were utilized as templates for synthesis of 3H-labeled complementary RNA (cRNA) by E. coli RNA polymerase, then ...
Cooke H J - - 1979
Two fragments cloned from purified human satellite III DNA do not cross-react with each other. One fragment, for which a partial sequence is reported, hybridises to satellite II as well as III and is shown to originate on chromosome 1. The other cloned fragment originates from the Y chromosome. This ...
Gosden J R - - 1979
The distribution of satellite DNA and nucleolar organiser activity have been studied in a female with a new dicentric translocation chromosome derived from the maternal chromosomes 13 and 14. More than half the satellite DNA (60.5%) was lost in the translocation, together with both the nucleolar organiser regions (NOR'S). However, ...
Carrano A V - - 1979
The 24 human chromosome types of normal diploid fibroblast cell strain were classified into 15 groups by high-resolution flow cytometry on the basis of 33258 Hoechst fluorescence. Chromosomes associated with each group were flow sorted onto microscope slides and identified by quinacrine banding analysis. DNA cytophotometry of metaphase chromosomes from ...
Singh L - - 1979
Sex chromosome associated satellite DNAs is isolated from the snakes Elaphe radiata (sat III) (Singh et al., 1976) and Bungarus fasciatus (Elapidae) (minor satellite) are evolutionarily conserved throughout the suborder Ophidia. An autosome limited satellite DNA (B. fasciatus major satellite) is not similarly conserved. Both types of satellites have been ...
Sigmund J - - 1979
In human lymphocyte cultures the frequencies of satellite associations in first, second, and third mitoses were investigated using the BUDR-method. A marked decrease of the association frequency with increasing numbers of cell cycles was found. The number of nucleoli seen in interphase is correlated with the satellite association frequency in ...
Verma R S - - 1979
A 43-year-old impotent male Caucasian had a chromosomal constitution of 46,XY,17ps+. The satellited chromosome 17 was also present in his sister. There is no suggestive evidence that this satellited chromosome causes any clinical abnormality. Based on multiple banding techniques, it is concluded that the 17ps+ is a rare chromosomal heteromorphism.
Wheeler L L - - 1978
Metaphase chromosomes of D. nasutoides were hybridized in situ with 3H-cRNA synthesized from the four satellites which make up 50--60% of the total DNA of this species. All four satellites were localized in the large, metacentric, heterochromatic chromosome four. They did not, however, appear to hybridize to centromeric or other ...
de Capoa A - - 1978
The frequency of involvement in satellite association and the frequency of selective staining of the secondary constrictions with silver solutions have been studied in five phenotypically normal individuals, all carriers of morphological variants of the nucleolus organizing region (NOR). The results show the preferential involvement of some morphological markers in ...
Ardito G - - 1978
In the present work 2526 metaphase plates were prepared from 28 normal adult individuals (12 male and 16 female) and then treated with the trypsin method in order to recognize the acrocentric chromosomes involved in the satellite associations. From our data it can be inferred that while the pattern of ...
Manuelidis L - - 1978
Complex repeating restriction multimers and a simple AT rich satellite isolated with Hoechst 33258 ( less than or equal to 0.5% of the human genome) were localized by in situ hybridization to human chromosomes. The complex repeats were clustered at the centromeres, consonant with their integration in tandem arrays at ...
Gosden J R - - 1978
In a family with a stable dicentric 13:14 translocation chromosome, the distribution of DNA sequences complementary to satellite DNAs I, II and III and ribosomal RNA were studied. The translocation chromosome showed a loss of sequences complementary to all three satellite DNAs, located in the short arms of the acrocentric ...
Zankl H - - 1978
The association pattern was studied in 2715 mitoses of 90 meningiomas with different numbers of acrocentric chromosomes. In cells with monosomy 22, a significant increase of mitoses with associations was observed in comparison to cells with a normal karyotype. The number of associating acrocentric chromosomes was highly significantly increased. This ...
Hansson A - - 1978
Studies of fluorescence and other chromosomal variants were informative in 26 out of 72 families. Maternal nondisjunction was found in 19 and paternal in 7 cases. Satellite association studies of these parents and 94 controls from the same age group showed a highly significant increase in the satellite association index ...
Gosden J R - - 1977
Human satellite DNAs I, II and IV were transcribed to yield radioactive complementary RNAs (cRNAs). These cRNAs were hybridised to metaphase chromosomes of man, chimpanzee (Pan troglodytes), gorilla (Gorilla gorilla) and orang utan (Pongo pygmaeus). The results of this in situ hybridisation were analysed quantitatively and compared with accepted chromosome ...
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