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71.
Biparental Phodopus campbelli and uniparental P. sungorus juvenile litters (2 males, 2 females) both consumed amniotic fluid and placenta during the birth of younger siblings. Three days later, P. campbelli juveniles were most responsive to a displaced younger sibling. Thus, P. campbelli are responsive to pups as juvenile alloparents and as new parents; however, at intervening ages, infanticidal attack (bite) was seen. At 5, 7, 9, 11, or 13 weeks of age, male and female P. campbelli were given a 5-min test with an unrelated, 3-day-old, anesthetized pup. Females attacked more often than males, yet pup-retrieval rates did not differ. Female aggression increased with age and was replaced by retrieval behavior 3 days after parturition. Male attack ceased after a birth, but parental behavior did not increase, remaining below the rate for new fathers tested with their own awake pup. Over repeated testing, behavior in one test did not predict behavior in another. Transitions from caregiving alloparent to infanticidal adult and back to parental care were clear in females, but less discrete with this stimulus paradigm in these highly paternal males. 相似文献
72.
The maternal dominance hypothesis has been derived from workwith humans which shows that women who are more dominant thanother women are more likely to conceive sons. In both animalsand humans dominance is a characteristic or personality trait,underpinned by testosterone and responsive to a range of environmentalchanges: physical, social and psychological. Studies of thesex ratio in the social sciences and animal behaviour eithersupport or are compatible with the idea that the sex-determiningrole of X- and Y-chromosome bearing spermatozoa may be precededby factors under maternal control which provide for differentialaccess of spermatozoa. Findings in reproductive physiology andphysiological psychology suggest that folh'cular testosteroneor a related hormone may play a critical role. Reproductivephysiologists have already identified maternal mechanisms whichcould provide the context for such a model. 相似文献
73.
Masafumi Ito Atsuko Nakagawa Atsuo Nakayama Yutaka Uno Izumi Takahashi Junpei Asai 《Pathology international》1990,40(2):149-152
Malignant salivary gland tumors in children are very rare. This report describes the autopsy of a child with parotid gland cancer. The patient, a 10 month old girl, was admitted to the Nagoya First Red Cross Hospital with facial nerve palsy. lncisional biopsy of a post-auricular tumor was performed, and undifferentiated carcinoma was diagnosed. The patient died 6 months later of respiratory failure due to pulmonary lymphangitis carcinomatosis. Light and electron microscopic and immunohistochemical examinations of the tumor tissue were performed. The tumor cells were arranged in a medullary, sheet-like manner. Keratinization or mucus lakes were not observed. PAS-alcian blue staining demonstrated intracytoplasmic mucus as granules, and also small intercellular droplets of mucus that might otherwise have been unnoticed. Ultrastructurally, some of the tumor cells had tonofilament-like keratin filaments, and also small hollow spaces bounded by microvilli and containing secretory particles. These were stained by antisera against CEA and keratin. These findings are suggestive of differentiation to mucoepider-moid carcinoma. We also review and discuss malignant salivary tumors of epithelial origin in children. Acta Pathol Jpn 40: 149–152, 1990. 相似文献
74.
子痫前期孕妇外周血及脐血中CD4+CD25+T细胞比例的变化 总被引:1,自引:0,他引:1
王轶英 《中国优生与遗传杂志》2008,16(8):20-21
目的 研究子痫前期孕妇外周血及脐血中CD4+CD25+T细胞的比例变化,探讨CD4+CD25+T细胞在妊娠免疫中的作用。方法 应用流式细胞技术检测孕妇外周血及脐血中CD4+CD25+T细胞的比例变化。结果 子痫前期孕妇外周血及脐血中CD4+CD25+T细胞比例较低,低于同孕期的正常妊娠组P〈0.05)。结论 CD4+CD25+T细胞在妊娠期高血压疾病的发生发展中发挥一定作用。 相似文献
75.
High risk pregnancies in hypopituitary women 总被引:1,自引:0,他引:1
Overton CE Davis CJ West C Davies MC Conway GS 《Human reproduction (Oxford, England)》2002,17(6):1464-1467
BACKGROUND: Various short papers have suggested that pregnancies in women with hypopituitarism are high risk but no formal assessment of pregnancy outcome has yet been reported. METHODS: An audit was carried out concerning the outcome of 18 pregnancies in nine women who underwent ovulation induction in a single centre over 20 years. RESULTS: The live birth rate was 61%, miscarriage rate 28% and mid-trimester uterine death rate 11% with no survivors from four sets of twins. The Caesarian section rate was 100% and half of the live births were on or below the 10th centile for weight. One woman successfully breast-fed. CONCLUSIONS: Women with hypopituitarism have high-risk pregnancies, perhaps because of a uterine defect secondary to endocrine deficiency. Fertility treatment must strive for singleton pregnancies with application of particularly strict criteria to avoid twin pregnancies. Early elective Caesarian section is probably warranted in this group. 相似文献
76.
Accumulation of atopic disorders within families: a sibling effect only in the offspring of atopic fathers 总被引:1,自引:0,他引:1
BACKGROUND: Several studies have reported an association between a child's risk of atopic disorders and family size. However, the inverse association might not be the same in populations with a different genetic disposition for atopic disorders. OBJECTIVE: This longitudinal study was designed to assess risk factors of atopy. METHODS: Lifetime prevalence of asthma, hay fever and eczema of 1440 families including 3165 offspring was ascertained by means of standardized questionnaires. RESULTS: After possible confounders had been controlled for, an inverse association between atopic disorders and the number of older siblings was found only in the offspring of atopic fathers (trend for older siblings: chi2 = 13.38, degrees of freedom [d.f.] = 1, P= 0.0002; odds ratio 'no older sibling'= 2.87 (95% confidence interval 2.18-3.78); '1 older sibling' = 2.11 [1.52-2.92], '2 older siblings' = 1.29 [0.74-2.23]; '3 or more older siblings' = 0. 15 [0.02-0.981). No such relationship was found for children without a history of paternal atopy (trend for older siblings: chi2 = 1.5 1, d.f. = 1, P = 0.22; odds ratio 'no older sibling' = 1 [reference]; '1 older sibling' =0.82 [0.63-1.06]; '2 older siblings' = 0.97 [0.67-1.40]; '3 or more older siblings' = 0.64 [0.31-1.33]). The trend for older siblings in the case of paternal atopy was significantly different from the trend for older siblings without a history of paternal atopy (chi2 = 8.68, d.f. = 1, P = 0.003). The number of younger siblings was not related to child's risk of atopy (trend for younger siblings: chi2 = 0.001, d.f. = 1, P = 0.97). CONCLUSIONS: Data from this study suggest a protective effect of sibship size only in children with a history of paternal atopy and if older siblings are present. The reason for this combined effect remains unclear. Thus, further investigations are needed to interpret the biological cause of the so called 'sibling effect'. 相似文献
77.
As an alternative to genetic theories of handedness, some theorists have offered an environmental mechanism, associated with birth stress, for the appearance of left-handedness. They suggest that brain damage as a result of birth difficulties can lead to a switch in hand preference from the right side to the left side. Consequently, one should find more left-handers in groups where the probability of the occurrence of birth stress is greater. Three studies are presented which explore the laterality of not only hand but also foot, eye, and ear, in a total of 5161 individuals, in an attempt to assess any relationship to birth stress. Maternal age seems to predict deviations from dextrality, dependent on the sex of the offspring, while paternal age and birth order do not. The use of a direct measure of conditions predisposing toward birth stress suggests that these results depend on prenatal or perinatal environmental trauma rather than chromosomal factors.This research was supported by grants from the Medical Research Council of Canada and from the Natural Sciences and Engineering Research Council of Canada, and represents an equal and shared contribution of both authors. 相似文献
78.
本实验取在分娩过程中的50对健康足月妊娠母亲的静脉血与其分娩的胎儿脐带血分别测定其血清中游离氨基酸的浓度,发现:(1)脐血中绝大多数氨基酸的浓度都显著高于母血。(2)分娩中产妇血清游离氨基酸总浓度高于非妊娠育龄妇女。(3)男性胎儿和女性胎儿的脐血氨基酸浓度除胱氨酸以外均无显著性差异。 相似文献
79.
We examined the interaction of the albino locus with the maternal environment on the behavioral development of two coisogenic strains of mice. Subjects of the pigmented C57BL/6 strain (=B6+/+) and of the albino C57BL/6c2J strain (=B6c/c) were either fostered by a mother of their own strain or cross-fostered at birth to an F1 hybrid dam. They were compared for the amount and daily distribution of activity displayed during 48 h in a seminatural device at weaning and when 75 days old. Food hoarding in the nest and food consumption at the food-search place were also recorded in adult subjects. When animals were fostered by a mother of their own strain, albino mice were more active and less nocturnal than pigmented mice at both ages. They hoarded less food in the nest and ate more at the food-search place. Most of these differences disappeared when both strains were fostered by an F1 dam. The amount of activity displayed during 48 h increased between 21 and 75 days of age. This increase was affected by cross-fostering to an F1 dam in B6c/c mice only. The developmental pattern of daily distribution of activity was changed by F1 dams in B6+/+ mice only. Whereas these influences of F1 dams produced subjects resembling the mother's phenotypic score, maternal effects on hoarding behavior in B6c/c mice produced subjects which did not resemble their foster mother. The results are discussed in terms of different possible ways of hereditary transmission of behavior and some methodological consequences are emphasized. 相似文献
80.
Bischoff FZ Sinacori MK Dang DD Marquez-Do D Horne C Lewis DE Simpson JL 《Human reproduction update》2002,8(6):493-500
Both intact fetal cells as well as cell-free fetal DNA are present in the maternal circulation and can be recovered for non-invasive prenatal genetic diagnosis. Although methods for enrichment and isolation of rare intact fetal cells have been challenging, diagnosis of fetal chromosomal aneuploidy including trisomy 21 in first- and second-trimester pregnancies has been achieved with a 50-75% detection rate. Similarly, cell-free fetal DNA can be reliably recovered from maternal plasma and assessed by quantitative PCR to detect fetal trisomy 21 and paternally derived single gene mutations. Real-time PCR assays are robust in detecting low-level fetal DNA concentrations, with sensitivity of approximately 95-100% and specificity near 100%. Comparing intact fetal cell versus cell-free fetal DNA methods for non-invasive prenatal screening for fetal chromosomal aneuploidy reveals that the latter is at least four times more sensitive. These preliminary results do not support a relationship between frequency of intact fetal cells and concentration of cell-free fetal DNA. The above results imply that the concentration of fetal DNA in maternal plasma may not be dependent on circulating intact fetal cells but rather be a product of growth and cellular turnover during embryonic or fetal development. 相似文献