Results 201 to 210 of about 30,070 (249)

Are double minutes chromosomes?

Experimental Cell Research, 1978
Double minutes of a human breast cancer cell line revealed no centromeres by Cd banding. They cluster at the periphery of metaphase plates, usually encased in a matrix material. They move in anaphase passively with the chromosomes by attaching to the sides or ends of the chromosomes.
P E, Barker, T C, Hsu
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Double Structure of Chromosomes

Nature, 1938
IN response to our demonstration1 that the metaphase chromosomes of Trillium are composed of four strands twisted about each other in pairs, while the anaphase chromosomes contain two intertwined threads, Dr. Darlington2 states that the appearance of two threads is an artefact induced by a fixative containing acetic acid, and due to “bubbles” arising ...
R. R. GATES, S. V. MENSINKAI
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Pathways to doubled haploidy: chromosome doubling during androgenesis

Cytogenetic and Genome Research, 2008
Production of doubled haploid (DH) plants through androgenesis induction is a promising and convenient alternative to conventional selfing techniques for the generation of pure lines for breeding programs. This process comprises two main steps: induction of androgenesis and duplication of the haploid genome.
J M, Seguí-Simarro, F, Nuez
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No Detectable Misrejoining in Double-Minute Chromosomes

Radiation Research, 1999
Pulsed-field gel electrophoresis combined with Southern hybridization and rare-cutting restriction endonuclease digestion has been used recently to quantify misrejoining of DNA double-strand breaks (DSBs) resulting from exposure to ionizing radiation. Measurements are made 24 h after a high dose of radiation.
B, Nevaldine, R, Rizwana, P J, Hahn
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Epidemiology of double aneuploidies involving chromosome 21 and the sex chromosomes

American Journal of Medical Genetics Part A, 2005
The chance of two chromosome abnormalities occurring in one conceptus is very small. However, some authors have suggested that double aneuplodies (DAs) might be more common than the product of their individual frequencies. The nonrandomness of such DA events was considered to be evidence that nondisjunction (NDJ) may be genetically determined.
Natalia V, Kovaleva, David E, Mutton
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HAPLOID PRODUCTION AND CHROMOSOME DOUBLING

Acta Horticulturae, 2006
In the applications of haploid plants, chromosome doubling has a major role and has been widely researched. Chromosome doubling restores fertility to plants and often results in genetically homozygous doubled haploids. In diploid and allopolyploid species these homozygous plants have the potential to become pure breeding new cultivars or the parents ...
K.J. Kasha, Y.S. Shim, E. Simion, J. Letarte   +3 more
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Chromosome Doubling in Monocots

2008
The development of efficient chromosome doubling protocols is essential for the useful application of doubled haploid (DH) plants in breeding programs, since frequency of spontaneous doubling is most of the time too low. Chromosome doubling has been traditionally applied to plantlets, being the colchicine the most widely anti-microtubule agent used in ...
A. M. Castillo, L. Cistué, M. P. Vallés, M. Soriano   +3 more
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Molecular biology of double‐minute chromosomes

BioEssays, 1993
AbstractDouble‐minute chromosomes play a critical role in tumor cell genetics where they are frequently associated with the overexpression of oncogene products. They have been observed for many years in light microscopic examinations of metaphase chromosomes from tumor cells, but their origin remains unknown and is the subject of considerable ...
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Chromosomal and Genetic Consequences of Chromosome Doubling

2002
Abstract Autotetraploids have four homologues that are capable of pairing. Only two chromosomes may be paired at any one position. However, different chromosomes may be paired at different positions. As a consequence, meiocytes in prophase and metaphase I of meiosis may contain quadrivalents.
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Chromosome doubling of 2x Solanum species by oryzalin: method development and comparison with spontaneous chromosome doubling in vitro

Plant Cell, Tissue and Organ Culture, 2003
A potato breeding scheme implies the possibility of ploidy level manipulation either by reducing the chromosome number of cultivars from 48 to 24 to be able to cross them with diploid related species or by doubling diploid material to reach the generally optimal tetraploid level.
Chauvin, Jean-Eric, Souchet, C., Dantec, J.P., Ellissèche, Daniel   +3 more
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