(n.) The development, or mode of origin, of the ova.
Example Sentences:
(1) During oogenesis in many animals there is a massive extrachromosomal synthesis of the genes for ribosomal RNA.
(2) The distribution of these molecules has been studied during oogenesis and during early post-fertilization development.
(3) By applying a number of quantitative nucleic acid hybridization procedures to both total and fractionated oocyte and somatic DNA, employing both homologous and heterologous U snRNA gene probes and suitable amplification and non-amplification control probes, we show that the U snRNA genes do not undergo any major amplification in Xenopus oogenesis.
(4) We assume that the relative content of 5S rRNA fractions reflects the proportion between ribosomes synthesized during oogenesis and those synthesized in embryos and larvae.
(5) The temperature-sensitive Drosophila developmental mutation, l(3)c21RRW630 (abbreviated RW630) disturbs oogenesis and has a maternal effect on embryogenesis.
(6) As the oocyte grows the amount of DNA in it increases rapidly, but at the end of oogenesis the increase in the amount of DNA lags considerably behind the rate of increase in the volume of the oocyte.
(7) The shorter cyclin B transcript alone is then detectable in the presumptive oocyte until stages 7-8 of oogenesis.
(8) Our results indicate that no significant differences exist in the rate of protein synthesis among any of the stages of oogenesis investigated.
(9) 6) Significant, lower frequencies of structural chromosome anomalies were observed irradiating earlier stages of mouse oogenesis.
(10) Eight stages in the oogenesis of Dermogenys pusillus were selected in order to demonstrate the formation of the egg membrane.
(11) The tudor (tud) locus of Drosophila melanogaster is required during oogenesis for the formation of primordial germ cells and for normal abdominal segmentation.
(12) The stages of embryogenesis of Polypodium closely correspond to stages of the host oogenesis.
(13) It is shown that E2-17 beta MCR changes significantly during the progress of oogenesis, mainly at the end of the sexual cycle.
(14) This treatment resulted in developmental retardation which was manifested in a number of ways: at the age of 30 days, the weight of the body was well as spleen, testes and particularly thymus was significantly reduced; histologically, the normal proportion of the red and white pulp in the spleen was changes; spermatogenesis (but not oogenesis) was markedly retarded corresponding to the age of 12-15 days in normal males; also skin displayed a persisting immaturity as reflected by an abundance of mast cells.
(15) Adult females homozygous for temperature-sensitive alleles exposed to the restrictive temperature during oogenesis produce embryos that show anterior segments with structures normally unique to the eighth abdominal segment, another transformation characteristic of polycomb-group mutants.
(16) This effect may have been related to differences in the environmental factors to whcih the two groups were exposed during oogenesis.
(17) They also suggest that the O-acetylated Neu5Gc and 9-O-Ac-KDN residues may have an important role during oogenesis.
(18) The microtubule array becomes progressively more complex and polarized during oogenesis; an extensive array of microtubules and microtubule bundles was apparent in the animal hemisphere of stage VI oocytes, and a less ordered array was observed in the vegetal hemisphere.
(19) The molecular and cytoplasmic organization of both axes originates during oogenesis and leads to the production of an ooplasmic system which consists of euplasm and deutoplasm (yolk) and contains a nucleus as well as extranuclear determinants of maternal origin.
(20) Serendipity delta (sry delta) is a member of a set of Drosophila zinc finger protein genes showing maximal transcription during oogenesis.
Spermatogenesis
Definition:
(n.) The development of the spermatozoids.
Example Sentences:
(1) An effective gonadal shield should reduce the gonadal dose to a level low enough to preserve spermatogenesis in most patients.
(2) The findings support our earlier suggestion that the kinetics of spermatogenesis in the quail are fundamentally similar to the pattern which has been described for mammals.
(3) Combined with histological analysis, these results suggest a more rapid recovery of normal spermatogenesis after physical insult with LAC treatment.
(4) The effect of the mutation for white belly spot controlled by the dominant gene W on spermatogenesis in mice was examined by experimental cryptorchidism and its surgical reversal.
(5) After 35 and 43 days, spermatogenesis was complete in 99.6% of the tubular cross sections, and most tubular cross sections were in stages IV-VII of the cycle of the seminiferous epithelium.
(6) The morphological process of spermatogenesis is largely unaffected and motile sperm are produced, but meiocyte aneuploidy is common.
(7) These results demonstrate that administration of a GnRH antagonist in the presence of constant serum T levels does not induce consistent azoospermia, and that the supporting effects of T on spermatogenesis cannot be explained exclusively on the basis of the testicular androgen concentrations.
(8) These injections suppressed peripheral FSH levels to 6% of the control values, suggesting that FSH might be the modulator of the effects on spermatogenesis.
(9) It is concluded that this new method of administration may have practical and pharmacokinetic advantages for the purpose of reversible inhibition of spermatogenesis.
(10) Whether this mechanism is thermoregulatory for the normal spermatogenesis cannot be inferred from the present work.
(11) The nuclei were isolated from boar spermatid or sperm cells at three distinct stages of spermatogenesis: just before the completion of a maturation process in the testis (late spermatid), immediately after a subsequent transformation into spermatozoa (caput spermatozoon), and after full maturation (cauda spermatozoon).
(12) Considering that chromatin reorganizations during spermatogenesis may be directly or indirectly related to changes of the nuclear lamina we have decided to further investigate lamin expression during this process.
(13) In addition, there is significantly less germ cell production from the primary spermatocyte stage of spermatogenesis onwards and the total number of Sertoli cells observed is less.
(14) An alternative explanation, that there may be a pre-existing defect in spermatogenesis, was tested in 20 post-pubertal males with acute torsion.
(15) In this study, we document the presence of significant mRNA levels for 5 different PKA subunits (RI alpha, RI beta, RII alpha, RII beta, and C alpha) in germ cells and demonstrate differential expression patterns for these subunits during spermatogenesis.
(16) While the results reflect antiandrogenic and antispermatogenic action of V. rosea, the selective retention of the spermatogonia provides scope for the much desired revival of spermatogenesis on cessation of the treatment.
(17) The solvent alone, hydroxypropyl cellulose, had some inhibitory effect on spermatogenesis.
(18) The regulation of cellular growth is essential in the developing testis and is required for the maintenance of spermatogenesis in the adult testis.
(19) Analysis of data on the influence of different metals (cadmium, cobalt, molybdenum) on the Drosophila melanogaster cells has revealed a considerable genotoxic effect of cadmium salts which manifests in the high percentage of cells elimination at the early stages of spermatogenesis--the premeiotic cells.
(20) Changes in the mode of DNA packaging in nuclei during spermatogenesis were studied by measuring of the fluorescence anisotropy decay of an ethidium dye intercalated in the DNA in whole nuclei.