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71.
72.
We present cytogenetic findings in 7 familial and 5 sporadic Alzheimer disease (AD) patients and 34 unaffected relatives, spouses, and normal controls. Our study was prompted by reports of increased chromosome abnormalities in patients and family members at risk for AD. Coded peripheral blood chromosome preparations were evaluated for aneuploidy, aberration rates, and banding patterns. Statistical analyses of our results showed no increase in aneuploidy or aberrations in AD patients, their relatives, or normals. Chromosome loss or gain in aneuploid cells was not specific except in two individuals. These two older persons studied, one with AD and one unaffected, were observed to have increased sex chromosome aneuploidy. This finding was attributed to aging and was not considered to be an effect of AD.  相似文献   
73.
The records of an ongoing Health Surveillance Registry that utilizes multiple sources of ascertainment were used to study the incidence rate of infantile hypertrophic pyloric stenosis (IHPS) in liveborn children in British Columbia during the period 1966–1977 inclusive. The incidence was 4.6 males/1,000 livebirths and 1.2 females/1,000 livebirths, giving a male to female ratio of 3.1 to 1. No significant overall incidence variations with time could be shown during the study period. There was suggestive evidence of independent sex-incidence variation in different geographical regions, which clearly warrants further investigation.  相似文献   
74.
Serum total IgE levels in a representative sample of a Greek population   总被引:1,自引:1,他引:1  
The distribution of IgE in a large randomly stratified Greek population sample was determined in 1187 subjects (793 men and 394 women) aged between 20 and 60 years. Skin prick testing was performed and serum total IgE expressed in iu/ml was measured by Phadebas PRIST: the data are presented as the geometric mean. Subjects were classified as atopic (257 men, 118 women) and nonatopic (536 men, 276 women) according to the results of skin testing with various aeroallergens. At any age, atopic males (120.5 vs 38 iu/ml) and females (99.8 vs 29.3 iu/ml) had higher mean IgE levels, as compared to nonatopic subjects ( P <0.0001). In our adult nonatopic sample, IgE levels did not differ with age ( P >0.05). At any age, nonatopic males had higher (38 iu/ml) mean IgE levels than nonatopic females (29.3 iu/ml) ( P <0.05). The comparison of normal IgE values (nonatopic subjects) from this study with those reported by other investigators revealed that Greek adult males and females had higher IgE levels than populations from other nations. Our results represent the first report on reference values regarding serum total IgE in Greek adults.  相似文献   
75.
对Bem性别角色量表的考察与修订   总被引:20,自引:1,他引:20  
目的:对在性别角色研究中使用得最为广泛的工具-Bem量表进行介绍,考察它在中国文化下的信、效度并进行修订。方法:选取两个城市三所大学中的340名本科生为被试。经过项目分析、因素分析等统计方法,对构成量表的条目进行删除和保留。结果:最后由14项男性化条目和12项女性化条目构成新的Bem量表简本。结论:修订后的Bem量表在信、效度上有了明显的提高,可以成为进一步研究的工具。  相似文献   
76.
Natural fluctuations in sex hormones during the ovarian cycle have enormous influences on ongoing psychological status in the female body. We report here studies of the effects of exogenous sex steroids on anxiety levels in female mice, as evaluated in the elevated cross maze test. Female NMRI mice were subjected to bilateral oophorectomy and one week later received s.c. injections of solvent (sesame oil, controls) or estradiol benzoate for 7 days, either alone or with an additional dose of progesterone on day 7. Elevated maze tests performed 6 h later showed that animals given progesterone had the highest levels of anxiety and the highest levels of grooming reactions as compared with the other groups. Immunohistochemical analysis of the distribution of progesterone receptors in different parts of the brain demonstrated significant increases in the numbers of immunopositive cells after injections of estradiol benzoate alone, with further increases after progesterone injections. Thus, the data obtained here suggest that the genomic effects of sex steroids are important, as they appear to be involved in non-sexual forms of behavior, particularly the level of anxiety.  相似文献   
77.
78.
Klinefelter syndrome (KS) has not typically been associated with mental retardation (MR), however, in recent years a growing body of evidence suggested that KS boys often experience language deficits and academic difficulties. In this study, we screened DNA samples from 1205 patients originally referred for fragile X syndrome (FRAX) testing, because of MR of unknown etiology and detected 8 KS patients. A similar number of males in the same age group were found to have FRAX; 3 of them had a family history of FRAX. Based on these findings, KS might be the most common cause of MR of unknown etiology among prepubertal males. Because of the significant benefits of early recognition and treatment of KS, we emphasize the importance of cytogenetic testing of all prepubertal males with cognitive impairment even without dysmorphic features.  相似文献   
79.
Autosomal dominant holoprosencephaly is a rare but well documented entity and it can be the result of mutations in the Sonic Hedgehog gene (SHH). The transmitting parent may be normal or have a single maxillary central incisor. We describe a skewed sex ratio among the transmitting parents with SHH mutations, with more mothers than fathers having the mutation (p=0.002). The mechanism underlying this skewed sex ratio is not clear; the SHH mutations do not involve triplet repeats, imprinting is plausible but untested, and there is no evidence that the risk of holoprosencephaly is greater among males carrying such a mutation (p=0.15). We considered the possibility that males with such a mutation are at greater risk of other malformations outside the central nervous system, which could reduce their reproductive fitness. To avoid ascertainment bias in identifying children with various malformations in kindreds with familial holoprosencephaly, we reviewed the reports of people with single maxillary central incisor and no other congenital malformations. Of the 16 cases identified, 13 were female (p=0.0085). We suggest that boys with mutations associated with autosomal dominant holoprosencephaly may be at greater risk of major malformations outside the central nervous system than girls.  相似文献   
80.
Individuals with Turner syndrome (TS) have a higher morbidity and mortality compared to the general population. Diabetes and cardiovascular disease are the major contributors to this burden. Precursors to diabetes and cardiovascular disease make up what is known as metabolic syndrome, including abdominal obesity, hypertension, dyslipidemia, and elevated fasting glucose. These features of poor cardiometabolic health are also prevalent among women with TS. Youth with TS also exhibit many of these features, indicating that the pathogenesis of these cardiometabolic conditions may begin early in life. The etiology of the increased risk of cardiometabolic conditions in TS is likely multifactorial, involving genetics, epigenetics, hypogonadism, medical comorbidities, medications, and lifestyle. Counseling for the increased risk of cardiometabolic diseases as well as efforts to prevent or lower this risk should be routinely provided in the care of all patients with TS. Clinical practice guidelines are now available to guide screening and treatment of cardiometabolic conditions in girls and women with TS.  相似文献   
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