Results 201 to 210 of about 34,110 (232)

Meiosis in the male mouse. An autoradiographic investigation

Chromosoma, 1970
Meiosis in the male mouse has been studied autoradiographically in air-dried preparations. Information has been obtained on the relative rates of DNA synthesis and the lengths of the S-periods in spermatogonia and spermatocytes. The average rate of synthesis in the spermatocyte is lower, and the S-period is of longer duration than the preceding ...
S, Kofman-Alfaro, A C, Chandley
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Meiosis in the Human Male

Cytogenetic and Genome Research, 1964
An improved technique for the preparation of meiotic chromosomes from human testicular biopsy specimens for microscopic examination is described. The results are exemplified by a description of the observations of the chromosomes at various stages of the first and second meiotic divisions in a normal male.
J.A. Böök, B. Kjessler
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Meiosis in a male with Down's syndrome

Chromosoma, 1965
The chromosomes in mitotic and meiotic phases were investigated in a male Down's syndrome case, aged 45. Information was obtained that based on blood and tunica vaginalis cultures, the somatic chromosome complement was found to possess 47 chromosomes with the standard 21-trisomy, and further that the majority of cells from biopsied testicular specimens
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Meiosis in Male Chorthippus

1965
In the species of the genus Chorthippus, as in a majority of the genera in the sub-family Truxalinae, the mitotic chromosome complement of the male includes seventeen members. Sixteen of these are autosomes and can be matched into eight homologous pairs; the seventeenth chromosome is unpaired and represents a sex or X-chromosome. All these elements are
Bernard John, Kenneth R. Lewis
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Endocrine Correlates of Meiosis in the Male Rat

Archives of Andrology, 1979
Changes in the proportion of cells within various DNA classes of dispersed testicular cells from the developing rat were monitored by microflow fluorometry and correlated with changes in the function of the pituitary (FSH), of the Leydig cells (androgens) and Sertoli cells (androgen-binding proteins, ABP).
O P, Clausen, K, Purvis, V, Hansson
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Retinoic acid regulation of male meiosis

Current Opinion in Endocrinology, Diabetes & Obesity, 2013
Description of new evidence to support the model for how retinoic acid regulates spermatogonial differentiation, male meiosis and the cycle of the seminiferous epithelium.It has been known since the 1920s that vitamin A is essential for spermatogenesis.
Cathryn A, Hogarth, Michael D, Griswold
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Meiosis-Inducing and Meiosis-Preventing Substances in Human Male Reproductive Organs

Fertility and Sterility, 1981
The initiation of meiosis is controlled by two substances, a meiosis-inducing substance (MIS) and a meiosis-preventing substance (MPS). These have been shown to be present in reproductive organs of both sexes of different mammals. In this investigation MIS and MPS were also shown to be present in man.
J, Grinsted, A G, Byskov
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Meiosis in the Male Periplaneta americana

Nature, 1963
CYTOLOGY of the common cockroach Periplaneta americana (Blattidae) dates back to 19091, and yet recent re-examination has not only brought to light interesting details, but also much controversy2–8. It was therefore felt necessary to examine the locally available species of cockroaches with the view of understanding the intricacies of the problem ...
M. R. RAJASEKARASETTY, C. V. RAMANAMURTHY   +1 more
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Effect of nitrofurantoin on meiosis of the male mouse

Human Genetics, 1977
The effects of nitrofurantoin [N-(5-nitro-2-furfurylidine)-1-amino-hydantoin] on chromosomes of primary and secondary spermatocytes of mice were studied. No mutagenic activity was detectable after application of either 8 mg/kg or 40 mg/kg nitrofurantoin.
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Cytogenetic Aspects of Human Male Meiosis

1973
During the first half of the present century human meiotic chromosomes were studied mainly in order to obtain information on the chromosome number of man. Different authors came to different conclusions regarding this number due to the fact that the only technique available for such studies was the use of histological sections from fixed testicular ...
M, Hultén, J, Lindsten
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