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21.
Serum progesterone concentrations in Galago crassicaudatus were quantified at 3-week intervals throughout the 136-day pregnancy. Progesterone concentrations were significantly elevated over those of nonpregnant controls as early as 6 weeks after conception. Progesterone continued to increase throughout gestation. The progesterone profile in pregnant G. crassicaudatus quantitatively resembles that of chimpanzees and qualitatively resembles that of humans. In two animals that aborted, progesterone concentrations after abortion decreased to values comparable to those seen in nonpregnant animals.  相似文献   
22.
Fifteen percent of women worldwide develop postpartum depression; however, many women also suffer from mood disorders during pregnancy. Our knowledge of how these stress-related disorders affect the neurobiology of the mother is very limited. In animal models, depressive-like behavior is often associated with repeated stress and alterations in adult neurogenesis in the hippocampus. However, research has yet to investigate the effect of stress on affective-like behavior and hippocampal neurogenesis in the pregnant female. The aim of the present study was to determine whether stress during gestation alters affective-like behaviors, corticosterone levels, and hippocampal cell proliferation and new cell survival in the pregnant female, and whether these effects differ from virgin females. Age-matched pregnant and virgin Sprague-Dawley rats were divided into two conditions: 1) stress and 2) control. Females in the stress condition were repeatedly restrained during gestation, and at matched time points in virgin females. Affective-like behaviors were assessed at the end of gestation, and at matched time points in virgin females. Results demonstrate that regardless of repeated restraint stress, pregnant females have increased anxiety-like behavior, decreased depressive-like behavior, and lower corticosterone levels, compared to non-stressed, and at times stressed, virgin females. In addition, stressed virgin females have lower levels of depressive-like behavior compared to control virgin females. Interestingly, hippocampal cell proliferation was increased in both virgin and pregnant females after stress. Understanding how stress affects the female during different reproductive states will aid in improving the health and well being of the mother and child.  相似文献   
23.
In the mature chorion, one of the membranes that exist during pregnancy between the developing fetus and mother, human placental cells form highly specialized tissues composed of mesenchyme and floating or anchoring villi. Using fluorescence in situ hybridization, we found that human invasive cytotrophoblasts isolated from anchoring villi or the uterine wall had gained individual chromosomes; however, chromosome losses were detected infrequently. With chromosomes gained in what appeared to be a chromosome-specific manner, more than half of the invasive cytotrophoblasts in normal pregnancies were found to be hyperdiploid. Interestingly, the rates of hyperdiploid cells depended not only on gestational age, but were strongly associated with the extraembryonic compartment at the fetal-maternal interface from which they were isolated. Since hyperdiploid cells showed drastically reduced DNA replication as measured by bromodeoxyuridine incorporation, we conclude that aneuploidy is a part of the normal process of placentation potentially limiting the proliferative capabilities of invasive cytotrophoblasts. Thus, under the special circumstances of human reproduction, somatic genomic variations may exert a beneficial, anti-neoplastic effect on the organism.  相似文献   
24.
Several behavioural effects of prenatal stress are reported in literature, and these seem to depend, among other factors, on the gender studied and the period of gestation in which prenatal stress is applied. In the present study, oral administration of hydrocortisone-acetate (HCA) to 41 pregnant sows was used as a model for prenatal stress, since corticosteroids are considered a key mediator in the effects of prenatal stress. HCA was orally administered to pregnant sows during three periods of gestation: 21-50 (period 1, P1, n = 10), 51-80 (period 2, P2, n = 10) and 81-110 (period 3, P3, n = 10) days after insemination (term 115 days). Control sows (n = 11) received vehicle from 21 to 110 days after insemination. Between days 9 and 48 after birth, treatment effects on male and female piglet behaviour were determined in the home pen and in four different behavioural tests. During the backtest, no gender differences were observed in vocalisations in HCA-piglets, while control males vocalised more than control females. In the home pen at 14 days of age, HCA-piglets spent less time in social interactions than control piglets. During the novel environment test, P1- and P3-piglets walked more than control piglets, but this was not observed during the novel object test, four days later. At weaning, P2- and P3-piglets performed less individual play. Prior to mixing with an unfamiliar piglet (male piglets only), HCA-piglets had lower salivary cortisol concentrations than control piglets, but no difference was observed after mixing. P1-, P2-, and P3- piglets had fewer non-aggressive encounters, and P2-piglets continued fighting longer than control piglets. The present study demonstrates that elevated maternal cortisol concentrations during gestation affect piglet behaviour, and effects do differ between male and female piglets. In addition, effects depend on the period of cortisol administration.  相似文献   
25.
目的:探讨孕妇妊娠期糖尿病对子代先天畸形风险的影响,为优生优育提供参考。方法:对我院妇产科收治的124例糖尿病孕妇的临床资料进行前瞻性分析,同时选取150正常孕妇作为对照组,运用产前超声对糖尿病孕妇和正常孕妇的胎儿的先天畸形进行对比分析。结果:妊娠期糖尿病孕妇子代的先天畸形的风险明显高于正常孕妇(RR=2.24,95%CI=0.85-5.88)。结论:孕妇妊娠期糖尿病可对子代的各系统先天畸形造成较大影响,对孕早期进血糖监测是必要的。  相似文献   
26.
笼养白眉长臂猿的繁殖初探   总被引:1,自引:1,他引:0  
潘阳 《四川动物》2000,19(2):88-89
本文报道了白眉长臂猿(Hylobates hoolock)在笼养条件下繁殖成功。经过笼养条件下3例白眉长臂猿繁殖结果的分析认为:舭舒环境、饲养、雌雄猿的配对以及雌猿自身哺育幼仔能力等,呈影响繁殖能否成功的因素。  相似文献   
27.
Progression through the cell cycle in eukaryotic cells is controlled by a family of protein kinases, termed cyclin-dependent kinases (CDKs), and their specific partners, the cyclins. In particular, the control of mammalian cell proliferation occurs largely during the G1 phase of the cell cycle. Five mammalian G1 cyclins have been enumerated to date: cyclins D1, D2, and D3 (D-type cyclins), and cyclins E and E2. By the use of immunohistochemistry and immunoelectron microscopy, we observed that in the first trimester of gestation of human placenta, cyclin D1 was distributed in the nuclei of the cytotrophoblast compartment together with a weak positivity of endothelial cells surrounding blood vessels. The endothelial positivity of cyclin D1 strongly increased in the third trimester of gestation. Moreover, we observed the subcellular localization of cyclin D1 that was present both in the stroma of placental villi and in the nuclei of syncytiotrophoblast cells. Therefore, we observed that CDK4 was localized in the nuclei of the cytotrophoblast compartment during the first and third trimesters and it also had a nuclear positivity in the endothelial cells of blood vessels at the end of the third trimester of gestation. In conclusion we may hypothesize that cyclin D1/CDK4 complex functions to regulate the cell cycle progression in the proliferative compartment of human placenta, the cytotrophoblast, during the first trimester through interaction with p107 and p130. Therefore, cyclin D1 and CDK4 seem to be involved in the control of placental angiogenesis during the third trimester of gestation.This work was supported by the University of Naples Federico II (M.D.F., V.F. and V.L.), by the Second University of Naples (L.C. and A.D.L.) and I.S.S.C.O. (President H.E. Kaiser)  相似文献   
28.
Pregnant Swiss albino mice were exposed to diagnostic levels of ultrasound (3.5 MHz, intensity 65 mW, I(SPTP) = 1 W/cm(2), I(SATA) = 240 W/cm(2)) for 10, 20 and 30 minutes on day 14 of gestation. Sham exposed controls were maintained for comparison. Fifteen pregnant mice were exposed for each group. Exposed as well as control animals were left to complete gestation and parturition. Ultrasound induced changes in maternal vaginal temperature was recorded. The changes in the physiological reflexes and postnatal mortality up to 6 weeks of age were recorded. The litters were subjected to behavioral tests for locomotor activity, learning and memory at 4 month and 1 year of age. Neither the physiological reflexes nor the postnatal mortality was affected by ultrasound exposure. However, there was a noticeable impairment in both locomotor and learning behavior even after a 10 min exposure, which further increased with increases in exposure time. Thus the present study demonstrates the neurotoxicity of diagnostic ultrasound and the high susceptibility of early fetal brain to induction of lasting detrimental changes by ultrasound exposure.  相似文献   
29.
圈养金钱豹的繁育   总被引:1,自引:0,他引:1  
金钱豹(Pantherapardus),属猫科食肉兽,活体观赏价值较高,骨骼则具有较高的经济和药用价值;过去它在我国分布较广,数量亦多,但因野外栖息地大幅度缩小,特别是乱捕滥猎致使其种群数量急剧下降,现濒于绝灭状态;《濒危野生动植物种国际贸易公约》(...  相似文献   
30.
Limited information is available on lysine requirement estimates of modern, high-producing gestating sows Therefore, the objective of this study was to evaluate the effects of increasing standardized ileal digestible (SID) lysine during gestation on piglet birthweight and reproductive performance of gilts and sows. A total of 936 females (498 gilts, 438 sows; Camborough®, PIC, Hendersonville, TN) were group-housed (approximately 275 females per pen) and individually fed with electronic sow feeders. Females were moved from the breeding stall to pens on d 4 of gestation and allotted to one of four dietary treatments on d 5. Dietary treatments included increasing SID lysine intake (11.0, 13.5, 16.0, and 18.5 g/d). Gilts (parity 1) and sows (parity 2+) received 2.1 and 2.3 kg (22.2 and 24.3 MJ net energy per day) of feed throughout the entire gestation period, respectively. Dietary treatments were achieved by different blends of low (0.48% SID lysine) and high (0.88% SID lysine) lysine diets, prepared by changing the amount of corn and soybean meal in these two diets. Female weight and backfat were recorded on d 4 and 111 of gestation. Individual piglet weight was obtained within 12 h of birth on litters from 895 females. Final weight, and calculated maternal BW, body lipid, and body lean at d 111 of gestation increased (linear, P < 0.01) for gilts and sows as SID lysine increased. There was no evidence for differences in final backfat depth. Average total born for gilts and sows was 15.3 and 16.0 pigs with no evidence for differences among treatments. The percentage of pigs born alive increased (P = 0.01) with increasing SID lysine intake for sows, but not in gilts as a result of a treatment by parity group interaction (P = 0.04) for percentage of stillborn pigs. Increasing SID lysine intake during gestation did not affect the percentage of mummified fetuses, total born, or birthweight of piglets born alive in this study. In addition, increasing SID lysine intake during gestation did not affect subsequent reproductive performance. In conclusion, increasing dietary SID lysine intake in gestation increased female BW, without changing backfat depth. The minimal effects on female reproductive performance and piglet birthweight suggest that 11 g/day of SID lysine intake appears to be adequate for gestating gilts and sows; however, providing sows with 18.5 g/d SID lysine reduced (P = 0.01) stillbirth rate by 2.3 percentage points.  相似文献   
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