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1.
S L Monfort S Jayaraman S E Shideler B L Lasley A G Hendrickx 《Journal of medical primatology》1986,15(1):17-26
Investigations were undertaken to determine the applicability of recently reported specific radioimmunoassays for urinary estrone conjugates and progesterone metabolites for monitoring ovarian function in the cynomolgus macaque (Macaca fasciularis) and other macaque species. Mean estrone conjugate measurements appear to accurately reflect the preovulatory estrogen peak in both conceptive (n = 5) and nonconceptive (n = 6) cycles, as well as to indicate early pregnancy through increases which are significantly elevated by Day + 15 (p less than 0.049) post estrone conjugates peak. The mean luteal phase levels of these progesterone metabolites are significantly elevated by Day + 14 (p less than 0.012) in conceptive cycles when compared to the mean values for nonconceptive cycles. 相似文献
2.
The influence of the source of pregnant mares' serum gonadotropin (PMSG) on the num ber, quality, and in vitro development of mouse embryos before and after freezing was evaluated among three genotypes: N:NIH(S), C57BL/6N, and C3H/HeN-MTV?. Immature females were given PMSG from one of five commercial sources. Following col lection ( 116 hr later), embryos were evaluated for stage of development, and four-to eight-cell embryos were pooled within genotype and assigned to standardized fresh or freeze-thaw culture trials. Different PMSG sources stimulated the production of different num bers of total embryos (P < 0.05) but not necessarily more embryos suitable for freezing. Differences in embryo production among genotypes indicated that absolute embryo num bers using a single mouse genotype may not accurately reflect the potency of a specific gonadotropin source. The PMSG source also affected the ability of an embryo to survive in culture either immediately after collection or after frozen storage. The effect, however, was genotype specific, with some mouse strains being relatively insensitive to PMSG source, whereas gonadotropin source played a major role in determining in vitro viability in others. Development rates for freshly collected embryos differed, often inconsistently, from those of thawed embryos regardless of the PMSG source used, demonstrating that fresh embryo development cannot be used to estimate expected post-thaw survival. In vitro development of thawed embryos is influenced not only by genotype, but also the source of the gonadotropin used to promote follicular development and oocyte maturation. These findings may explain, in part, the wide variation in embryo viability and culture rates reported among laboratories and intraspecies animal populations. 相似文献
3.
The Aspergillus nidulans endoxylanase X24 and the Aspergillus oryzae (alpha)-amylase cDNAs were placed under the control of the Saccharomyces cerevisiae actin promoter (pACT1) and introduced into baker's yeast. Bread made with transformants expressing both enzymes (YEpACT-AMY-ACT-X24) showed a 30% increase in volume and reduced firmness in comparison with that produced with a commercial strain. Endoxylanase X24 and (alpha)-amylase seem to act synergistically to improve the quality of bread in terms of volume and density. 相似文献
4.
R. Aledo R. Raz A. Monfort C. M. Vicient P. Puigdomènech J. A. Martínez-Izquierdo 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1995,90(7-8):1094-1100
This paper describes the characterization and chromosomal distribution of new long repetitive sequences present in all species of the genus Zea. These sequences constitute a family of moderately repetitive elements ranging approximately from 1350 to 1700 copies per haploid genome in modern maize (Zea mays ssp. mays) and teosinte (Zea diploperennis), respectively. The elements are long, probably larger than 9 kb, and they show a highly conserved internal organization among Zea subspecies and species. The elements are present in all maize chromosomes in an interspersed pattern of distribution, are absent from centromeric and pericentric heterochromatin, and with some clustering in the distal regions of chromosome arms. 相似文献
5.
The transposon Mutator was first identified in maize, and is one of the most active mobile elements in plants. The Arabidopsis thaliana genome contains at least 200 Mutator-like elements (MULEs), which contain the Mutator-like transposase gene, and often additional genes. We have detected a novel type of MULEs in melon (CUMULE), which, besides
the transposase, contains two ubiquitin-like specific protease-like sequences (ULP1). This element is not present in the observed
location in some melon cultivars. Multiple copies of this element exist in the Cucumis melo genome, and it has been detected in other Cucurbitaceae species. Analysis of the A. thaliana genome revealed more than 90 CUMULE-like elements, containing one or two Ulp1-like sequences, although no evidence of mobility exists for these elements. We detected various putative transposable elements
containing ULP1-like sequences in rice. The discovery of these MULEs in melon and Arabidopsis, and the existence of similar
elements in rice and maize, suggest that a proteolytic function may be important for this subset of the MULE transposable
elements.
Electronic supplementary material Supplementary material is available in the online version of this article at and is accessible for authorized users.
Nucleotide sequence data reported are available in the GenBank database under the accession number AY524004. 相似文献
6.
7.
Sperm capacitation was examined in the endangered Eld's deer (Cervus eldi thamin). Sperm motility and viability (percentage of sperm cells with intact membranes) were assessed in vitro over time after attempting to induce capacitation in TALP alone and TALP supplemented with calcium (10 mM CaCl2), dibutyryl cAMP (1 mM dbcAMP), or fetal calf serum (20% FCS). Sperm aliquots were evaluated at 0, 3, 6, 9, and 12 h for motility, viability, and ability to acrosome react after exposure to calcium ionophore (A23187, CI; 10 microM) or lysophosphatidylcholine (LC; 100 microg/mL). Fresh sperm aliquots in TALP + 10 mM CaCl2 exposed to CI had fewer (P < 0.05) intact acrosomes than the TALP control (TALP alone) or dbcAMP and FCS treatments after 9 h. Mean (+/- SEM) percentage of intact acrosomes of spermatozoa incubated in medium with increased CaCl2 declined (P < 0.05) from 80.2 +/- 2.6% (0 h) to 49.7 +/- 7.3% after prolonged incubation (9 h). The proportion of capacitated fresh spermatozoa was not influenced by LC treatment. Capacitation was not induced (P > 0.05) by any of the presumptive sperm capacitators after freeze-thawing. Likewise, neither CI nor LC induced the acrosome reaction (AR) in these spermatozoa, suggesting that the freeze-thawing process may have caused membrane damage. Results revealed that the supplementation of medium with CaCl2 evokes capacitation in some spermatozoa. However, Eld's deer spermatozoa appear remarkably resistant to conventional stimulators of capacitation and the AR. 相似文献
8.
Recent research demonstrated the utility of fecal progestagens (P4) for detecting pregnancy in elk (Cervus elaphus) during mid- to late gestation. Several factors, however, may influence fecal P4 excretion and limit its use in free-ranging animals. We investigated the effects of nutrition and body condition (percent ingesta-free body fat) on fecal P4 concentrations and incidence of abortion. During mid-gestation (late December 1997 through early March 1998), 40 gravid cow elk varying in body condition were placed on three diets (high, medium, and low) in which the amount of food offered varied. Feces were collected periodically and analyzed for P4 via radioimmunoassay. We found no significant effect of dietary treatment on P4 concentrations, but as body condition declined, P4 concentrations declined significantly. This decline did not impede the ability to detect pregnancy based on previously reported criteria, even for elk in such poor condition that they aborted. However, fecal P4 concentrations in 10% (4/39) of samples collected from 13 non-pregnant animals maintained on a high plane of nutrition were false-positive for pregnancy. We suggest alternate criteria for determining pregnancy in elk using fecal P4 values: > 1.25 micrograms/g feces as pregnant, < 1.0 microgram/g feces as non-pregnant, and 1.0-1.25 micrograms/g feces as inconclusive. Finally, two cows that aborted did not abort until weeks after being classified as emaciated and near death, suggesting that nutrition-associated abortion in elk may not occur during mid-gestation except under extremely harsh conditions. 相似文献
9.
10.
Morrow CJ Wolfe BA Roth TL Wildt DE Bush M Blumer ES Atkinson MW Monfort SL 《Animal reproduction science》2000,59(1-2):71-86
Ovarian response and pregnancy success in scimitar-horned oryx (n=28) were compared, following treatment with two synchronization protocols and fixed-time artificial insemination (AI) with frozen-thawed semen. Each oryx received two injections of 500 microg of prostaglandin-F(2alpha) analogue (PGF(2alpha)-only) 11 days apart, and half received PGF(2alpha) in combination with an intravaginal progesterone-releasing device (CIDR11+PGF(2alpha)). Semen was collected by electroejaculation from anaesthetised adult oryx and cryopreserved. Anaesthetised females were transcervically inseminated 56.0+/-1.1 h (+/-S.E.M.) after PGF(2alpha) injection and/or device withdrawal using 28.0+/-1.5x10(6) motile thawed sperm. Ovarian endocrine response was monitored in 20 females by analysing faecal oestrogen and progesterone metabolites. Periovulatory oestrogen peaks were detected in 19/20 (95%) females after synchronization. There were no between-treatment differences in oestrogen concentrations or peak characteristics (P0.05). Luteal development after synchronization was delayed in half the progesterone treated (CIDR11+PGF(2alpha)) females, and faecal progestin excretion profiles indicated that the ovulatory follicle associated with synchronization either failed to ovulate or to fully lutenise. Pregnancy was diagnosed by ultrasonography and/or rectal palpation and was monitored by faecal progestin excretion. More (P=0. 013) pregnancies resulted from the PGF(2alpha)-only treatment (37.5%, 5/14) than from the CIDR11+PGF(2alpha) treatment (0/14), and four healthy scimitar-horned oryx calves were born, three after gestation intervals of 247 days and one after 249 days. 相似文献