Results 221 to 230 of about 30,580 (249)

Origin of chromosomal abnormalities: Evidence for delayed fertilization in meiotic nondisjunction

Human Genetics, 1983
This study ascertained 35 aneuploid patients, of which 34 had trisomy 21 and one had trisomy 18. Their parents were matched by age at the conception with parents of 35 euploid patients with congenital defects. Interviews with the couples focused on exposures and activities at the time of the conception. No parents had infectious hepatitis preceding the
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SPONTANEOUS MEIOTIC CHROMOSOME ABNORMALITIES IN MALE MICE (MUS MUSCULUS)

Canadian Journal of Genetics and Cytology, 1971
Three types of spontaneous meiotic chromosome aberrations were described in mouse spermatocytes: (1) Precocious separation of XY chromosomes was observed in about 6% of cells in diakinesis and first metaphase; (2) chromosome degeneration appeared in 9.2 and 4.8% of cells at pachytene and at first metaphase, respectively; (3) polyploidy, in particular ...
C C, Lin, W S, Tsuchida, S A, Morris
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First meiotic division abnormalities in human oocytes: mechanism of trisomy formation

Cytogenetic and Genome Research, 1994
Trisomy is the single most frequent type of chromosome abnormality in humans and has considerable impact on many aspects of human pathology. It arises most commonly through “nondisjunction” at maternal meiosis I, but the underlying mechanism of formation remains obscure.
R R, Angell, J, Xian, J, Keith, W, Ledger, D T, Baird   +4 more
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DNA fragmentation and meiotic segregation in sperm of carriers of a chromosomal structural abnormality

Fertility and Sterility, 2009
To determine the meiotic segregation and DNA fragmentation in spermatozoa of carriers of a chromosomal structural abnormality.Case series.University hospital.Thirty-seven male carriers of a chromosomal structural abnormality (21 with a balanced reciprocal translocation, 7 with a robertsonian translocation, 9 with a pericentric inversion).Meiotic ...
Aurore, Perrin, Emilie, Caer, Maria, Oliver-Bonet, Joaquima, Navarro, Jordi, Benet, Véronique, Amice, Marc, De Braekeleer, Frédéric, Morel   +7 more
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A new meiotic abnormality inZea mays: multiple spindles associated with abnormal cytokinesis in both divisions

Genome, 2001
We report here a new meiotic abnormality recorded in one plant of an inbred line of Zea mays. After an apparently normal prophase I, chromosomes did not congregate in a single metaphase plate. Bivalents remained scattered in the cytoplasm, giving rise to several spindles.
C M, Caetano-Pereira, M S, Pagliarini
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Microsporogenesis and meiotic abnormalities in the hybrid complex of Phlomis composita (Lamiaceae)

Botanical Journal of the Linnean Society, 2003
The extent of chromosome structural differences such as permanent translocations and paracentric inversions has been studied in the hybrid complex of Phlomis composita and its putative parental taxa P. lychnitis and P. crinita. They are detected as meiotic abnormalities during microsporogenesis.
ABELARDO APARICIO, RAFAEL G. ALBALADEJO
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[Diagnosticum of abnormalities of plant meiotic division].

Tsitologiia, 2006
Abnormalities of plant meiotic division leading to abnormal meiotic products are summarized schematically in the paper. Causes of formation of monads, abnormal diads, triads, pentads, polyads, etc. have been observed in meiosis with both successive and simultaneous cytokinesis.
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[Abnormalities of meiotic recombination in Han Chinese azoospermic patients].

Zhonghua yi xue yi chuan xue za zhi = Zhonghua yixue yichuanxue zazhi = Chinese journal of medical genetics, 2012
To analyze defective homologous chromosomal recombination in Han Chinese azoospermic patients.Testicular biopsy samples from 7 healthy controls and 7 Han Chinese azoospermic patients including 2 obstructive azoospermia (OA group) and 5 non-obstructive azoospermia (NOA group) were analyzed.
Xiao-jin, He, Qing-ling, Yang, Zhen-zhen, Pan, Huan, Wu, Liu, Wang, Qing-hua, Shi, Ji-hua, Zhao, Yun-xia, Cao   +7 more
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[Cytoskeleton abnormalities and meiotic restitution in the higher plants].

Tsitologiia, 2006
Cytoskeleton abnormalities leading to the formation of restitution nuclei, and to the reunion of segregated daughter chromosome groups in the higher plant meiosis are reviewed.
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[Effect of emotional stress on the frequency of meiotic abnormalities in male mice].

Genetika, 1986
The effect of stress on the recombination frequencies at the 1st and 2nd chromosomes of male mice was shown earlier. The purpose of this work is the study of the stress effects on the behaviour of meiotic chromosomes. Male mice (A/He and DD/J inbred strains) were treated with acute immobilizing stress at different periods, prior to killing.
I P, Gorlov, P M, Borodin
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