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1.
V. Fuster 《HOMO》2011,62(6):500-509
Using data from parish and civil registers in a rural community in northwest Spain (Los Nogales), family reconstitution provided 1502 complete reproductive histories, of which 584 corresponded to first marriages of women dying after their 50th birthday. A homogeneous sample consisting of women married in the period 1877–1899 (N = 311) provided information concerning their reproductive performance, including ages at first and last maternity and number of children born alive and surviving, which was related to the mother's post-menopausal longevity, also considering premarital fertility and her marital status (widow/married). The results obtained indicate that mothers with a lower proportion of children dying before the first birthday and the age of 15 (mainly males) have a greater post-reproductive longevity. Moreover, women with a more protracted end to their reproductive period and greater fertility live for more years beyond their 50th birthday. These results do not prove a causality between maternal longevity and more successful reproduction; instead, they are indicative of a holistic condition of health. A wide spectrum of favorable biological and environmental factors will have positive consequences for a woman's life trajectory, affecting both her reproductive performance and her own likelihood of surviving.  相似文献   

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Fibroblast growth factor (FGF) signaling is essential for the development of the gonadotropin-releasing hormone (GnRH) system. Mice harboring deficiencies in Fgf8 or Fgf receptor 1 (Fgfr1) suffer a significant loss of GnRH neurons, but their reproductive phenotypes have not been examined. This study examined if female mice hypomorphic for Fgf8, Fgfr1, or both (compound hypomorphs) exhibited altered parameters of pubertal onset, estrous cyclicity, and fertility. Further, we examined the number of kisspeptin (KP)-immunoreactive (ir) neurons in the anteroventral periventricular/periventricular nuclei (AVPV/PeV) of these mice to assess if changes in the KP system, which stimulates the GnRH system, could contribute to the reproductive phenotypes. Single hypomorphs (Fgfr1(+/-) or Fgf8(+/-)) had normal timing for vaginal opening (VO) but delayed first estrus. However, after achieving the first estrus, they underwent normal expression of estrous cycles. In contrast, the compound hypomorphs underwent early VO and normal first estrus, but had disorganized estrous cycles that subsequently reduced their fertility. KP immunohistochemistry on Postnatal Day 15, 30, and 60 transgenic female mice revealed that female compound hypomorphs had significantly more KP-ir neurons in the AVPV/PeV compared to their wild-type littermates, suggesting increased KP-ir neurons may drive early VO but could not maintain the cyclic changes in GnRH neuronal activity required for female fertility. Overall, these data suggest that Fgf signaling deficiencies differentially alter the parameters of female pubertal onset and cyclicity. Further, these deficiencies led to changes in the AVPV/PeV KP-ir neurons that may have contributed to the accelerated VO in the compound hypomorphs.  相似文献   

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Three micro algae, Ankistrodesmus convolutus, Scenedesmus incrassatulus and Chlorella vulgaris, at three concentrations, were tested as diets for Moina macrocopa. Their effect on reproduction, fecundity, growth and survival was evaluated. All three algae satisfied the nutritional requirements of M. macrocopa, despite their difference in size. The best concentration, expressed in dry weight, was 5 mg l–1 for all three. Time to first reproduction was 4 days with all diets. Average time between clutches was 33 hours, and maximum number of clutches was 12; the highest average number of offspring per brood was 27. The largest broods were the fourth to sixth, depending on the diet. Ephippium hatching depends on temperature, taking only 24 hours at 30 °C and 48 hours at 27 °C. This species could be an important test organism in aquatic bioassays, and a live food in aquaculture.  相似文献   

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Pouched mice were kept under controlled conditions of illumination (10D:14L) and temperature (22 +/- 2 degrees C). Age at vaginal opening, first oestrus and first conception did not differ significantly between juvenile females raised singly, in single-sex groups of 5, or with an adult male. After the introduction of a male, sterile cycles and/or matings before first conception were experienced by all females whether they were raised singly or in single-sex groups. Of 10 females raised with a male, 4 conceived at their first mating. Onset of puberty in juvenile females raised with an adult female was delayed, while in juvenile females raised with their families (mother, father and litter mates) only vaginal opening was delayed. However, when raised in family groups without the father, vaginal opening as well as first oestrus were delayed. Grouping of females after weaning, with or without a male, did not change the oestrous cycle pattern. Females in these groups cycled independently of each other and the females grouped with a male also mated and conceived independently of each other. Pregnancy was blocked in 7 of 8 females when the stud male was removed and a strange male was introduced. In females exposed to a succession of males, pregnancy was blocked up to 4 times.  相似文献   

6.
One hundred forty pubertal Swiss-Webster female mice (Mus musculus) were assigned randomly to a purified diet modified to contain 1, 2, 3, 4, 5 and 6 ppm copper as copper carbonate (Diets 1 thru 6, respectively). Diet 7 was a commercial rodent laboratory diet containing 11 ppm copper. Following 60 days of prefeeding, the breeding regimen was initiated by introducing a proven breeder male into each cage of 10 females in the afternoon and removing them the next morning. The breeding regimen was conducted for 28 days and females were either sacrificed at 24 or 96 hours following detection of a vaginal plug. Body weight, hematocrit, heart weight, hemoglobin concentration, ova recovery rate and fertilization rate were recorded for each female. All morphologically normal embryos collected 24 hours after detection of the vaginal plug were cultured and development in vitro evaluated. Body weight, hemoglobin concentration and hematocrit were lower (P less than .05), and heart weight and percent body weight occupied by the heart (%BWOH) were higher (P less than .05) in mice fed Diet 1. Heart weight and %BWOH were not different among mice fed Diets 2 thru 6 (P greater than .05). Ova recovery rate and fertilization rate were significantly reduced in mice maintained on Diet 1. The incidence of in vitro blastocyst formation was lower in embryos collected from females fed Diets 1 and 3 (P less than .05). Blastocyst hatching in vitro was not observed in embryos from females maintained on Diet 1, and was greater in embryos from females fed Diets 4, 5, and 7 (P less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

7.
Trade-offs between growth and reproduction in female bison   总被引:6,自引:0,他引:6  
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8.
C3H mice including aged retired breeding females, aged virginal females, young virginal females and young males were examined for the incidence and severity of pulmonary calcification. Pulmonary calcification appeared in aged females, but not in young mice of either sex, and the lesions in aged breeders were more severe and frequent than in aged virgins. These results indicate that spontaneous pulmonary calcification is observed in aged females of the C3H strain. The findings of increased incidence and severity of pulmonary lesions in aged breeders suggest that pregnancy, delivery and lactation are important enhancing factors. Calcified lesions were also observed in kidney, heart, brain, ovary, choroid plexus, cornea and artery in the animals examined.  相似文献   

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Female C3H/Bi mice develop spontaneous viral mammary carcinoma which can metastasize to the lungs. Two hundred and forty tumoral mice were either exposed to a toro?dal pulsed magnetic field, 12 Hz, 100 Hz or 460 Hz in frequency or used as controls. The exposure was mainly done 10 min. a day, 3 days a week, or 30 minutes once a week from about 2 to 3 weeks after the appearance of the tumors until death. In comparison with the controls, the exposed mice showed lighter spleens and lungs; this last observation could mean fewer pulmonary metastases. The weight of the tumors has been found lighter for 460 Hz MF, not changed for 100 Hz MF, heavier for 12 Hz MF, but lifespans were not altered by the exposure.  相似文献   

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Free growth and post-Doxorubicin treatment regrowth of the C3H mammary carcinoma were analysed in individual mice. In both cases, the Gompertzian function provided a better fit than the exponential function, and the difference was statistically significant (P less than 0.001, chi 2 test). No comprehensive Gompertzian function was found, and each individual tumour growth or regrowth was described by a specific curve. Nevertheless, although both individually measured alpha 0 and beta, Gompertzian parameters varied from one animal to another, in both free-growing and post-treatment regrowing tumours a strong linear correlation between alpha 0 and beta was found. A parallelism test was performed to verify if there exists any treatment-induced alteration. The two regression lines appeared to be identical, however.  相似文献   

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Summary Multinucleate epithelial cells occur in the thymus of C3H mice. They are poorly differentiated and scarce, but are more numerous in the medulla than in the cortex. Their increase in number with age is particularly significant between the first and the third months especially for cells with a large number of nuclei, and may be related to thymic involution.Viral particles of type C, similar to those described in murine leukemias, are found in mono- and multinucleate medullary epithelial cells.Research supported by grant 10.013 of the Fonds de la Recherche Fondamentale Collective (Brussels)  相似文献   

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A diurnal rhythmicity in plasma corticosterone levels was demonstrated in female BALB/cCrgl and C3H/Crgl mice, with and without mammary tumor virus. Removal of the adrenals followed by metopirone treatment reduced circulating corticoid to non-detectable levels in C3H but not in BALB/c mice. Dexamethasone strains. Neonatal exposure to exogenous hormones failed to cause any obvious change in corticoid levels. Bilateral ovariectomy of these neonatally treated mice at 40 days of age resulted in a subsequent lowering of plasma corticoid levels when compared with intact animals.  相似文献   

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Growth,reproduction and longevity in nematodes from sewage treatment plants   总被引:1,自引:0,他引:1  
The growth, reproduction and longevity of Diplogasteritus nudicapitatus, Paroigolaimella bernensis and Rhabditis curvicaudata were investigated under conditions of excess food within the temperature range 5°C–20°C. In all three species growth rate increased with temperature, and in D. nudicapitatus and R. curvicaudata the adult size attained varied significantly with temperature. P. bernensis did not reproduce at 5°C, but showed a progressive increase in reproductive output at higher temperatures. D. nudicaitatus showed increased egg production as temperature increased while R. curvicaudata had maximum egg output at 10°C. Longevity is temperature dependent, decreasing with higher temperatures. Virgin females survived for longer than reproducing females. The data indicate that while D. nudicapitatus and P. bernensis are thermophilic species, R. curvicaudata is adapted to lower temperatures.  相似文献   

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