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51.
A homologue of the bifunctional sex-determining gene, doublesex (dsx), has been identified in the tephritid fruit fly, Bactrocera tryoni, and has been found to be expressed in a sex-specific manner in adult flies. The male- and female-specific cDNAs are identical at their 5′ ends but differ at their 3′ ends and appear to be the products of alternate splicing. The level of identity of the sex-specific DSX proteins of B. tryoni with the D. melanogaster DSX proteins, across the region corresponding to the DNA binding domain and the oligomerization domains, is greater than 85%. Four sequence motifs which are ten to thirteen bases identical to the TRA/TRA-2 binding sites (thirteen-nucleotide repeat sequences) are present in the female-specific exon of the B. tryoni dsx gene.  相似文献   
52.
There is considerable evidence that sex differences in spatial ability exist in adults, with males outperforming females at every age after puberty. It is difficult, however, to find sex differences in children younger than 13. This is due in part to the lack of adequate measures of spatial ability for use with children. We report the use of spatial tests for children that are similar to those that have shown large sex differences in adults and may be measuring ability comparable to adult spatial ability. Four tests of mental rotation and spatial visualization were given to two samples of children. The first sample consisted of 81 children (39 males and 42 females) aged 9 to 12 years. The second sample consisted of 42 children (21 males and 21 females) aged 9 to 13 years. Sex differences of .4–.6 standard deviations were found on three tests in both samples. These results indicate that sex differences in spatial ability can be found in preadolescents if appropriate tests are used. Measurement of these abilities in children facilitates the investigation of possible biological and sociocultural contributors to the sex differences in spatial ability.This study was supported by National Institutes of Health Grant HD19644 and NIH Biomedical Research Support Grant S07 RR05366-24.  相似文献   
53.
54.
Parental alcoholism and early child development   总被引:2,自引:0,他引:2  
In a cohort of 532 pregnant women from the general population, it was found by compilation of the results from interviews, police records, hospital records and social welfare records that 23 mothers and 51 fathers in 64 families (12%) were suffering from alcoholism/heavy drinking. In these 64 families, the mother was an addict in only 13 families, both parents were addicts in 10 families, and in the remaining 41 families only the father was an addict. Pregnancy, delivery, the newborn child and the child's development until their fourth year of life have been described using a multidisciplinary approach and a longitudinal prospective design. An hypothesis on mental and physical development, and the occurrence of psychopathological symptoms in the children was tested. None of the children of the 13 alcoholic mothers was born with foetal alcohol syndrome, but foetal hazard was indicated by lower birth weight and a higher rate of perinatal deaths. Children of alcoholic parents had retarded mental development and showed more behavioural problems until 4 years of age than controls, but the differences related to physical development during the first year of life had then disappeared. Boys were found to be more vulnerable than girls. The consequences of behaviour seemed to be more pronounced when both parents were alcoholics. No obvious deviation was found when only the father was addicted. Regarding mental development, it appears that factors related to parental alcoholism, including genetic and social factors, and the sex of the child, are of greater importance than the neonatal score on reduced optimality.  相似文献   
55.
目的:为了解阴道毛滴虫在性罪错人群寄生的情况,探讨和分析阴道毛滴虫寄生与性罪错人群间可能存在的联系。方法:对南通市公安局收容教育所性罪错人群以及本市某国营纺织厂健康纺织女工阴道毛滴虫的寄生情况进行了6个月~1年的连续性观察。对1998~2001年间南通市公安局收容教育所性罪错人群3490人和随机抽样国营纺织厂纺织女工284人分别采用生理盐水涂片法镜检阴道毛滴虫滋养体。结果:性罪错人群中淋病双球菌、解脲文原体、沙眼衣原体和梅毒螺旋体感染者阴道毛滴虫滋养体的平均阳性检出率为31.54%,明显高于正常对照组(2.46%,7/284),差异非常显著(x~2=29.97,P<0.005),并且淋病双球菌、解脲支原体、沙眼衣原体和梅毒螺旋体混合感染者,阴道毛滴虫滋养体的阳性检出率高于单纯淋病、解脲支原体感染、沙眼衣原体感染和梅毒螺旋体感染者。结论:建议性罪错人群在接受淋病双球菌、解脲支原体、沙眼衣原体、梅毒螺旋体时,甚至包括艾滋病毒等特异性检测的同时,必须常规检查阴道毛滴虫滋养体,尤其应当高度重视性传播疾病混合感染,务必选用抗性病和抗滴虫相结合的治疗方法,有利于患者迅速痊愈。  相似文献   
56.
Steady-state nerve growth factor (NGF) mRNA levels were estimated in male sex organs of the mouse, rat, and guinea pig by RNA blot hybridization analysis. The abundance of NGF mRNAs was in the order vas deferens greater than epididymis greater than or equal to seminal vesicles much greater than testis. NGF mRNA levels in these organs were compared with those estimated for other rat peripheral tissues and were found to correlate with the density of their sympathetic innervation, with the exception of guinea pig prostate. Castration had no significant effect on NGF mRNA levels in the guinea pig prostate, suggesting that NGF synthesis in this tissue is not under direct androgen control. NGF-like and proNGF-like immunoreactivities were localized by immunohistochemical techniques in the secretory cells of the glandular epithelium of the guinea pig prostate and in germ cells in the seminiferous tubules of the mouse testis.  相似文献   
57.
During the years 1959 to 1983 a doubling in the rate of homicide took place in Copenhagen. This increase was exclusively due to an increasing number of male offenders. By comparing with another Danish material, the frequency of female homicide as well as that of homicide combined with suicide was found practically unchanged since 1946, indicating that both of these kinds of homicides seem to have a background different from those of other offences of fatal violence. During the years 1959 to 1983, the criteria of selection of the defendants for a psychiatric examination for the court were fairly consistent. Examinations were performed in practically all cases, where a charge of murder raised by the police was followed by a legal trial for homicide. Less and less of the defendants, however, were hospitalized for the examination, while more were examined in The Clinic of Forensic Psychiatry in Copenhagen.  相似文献   
58.
目的:观察丙氨瑞林对子宫内膜癌的治疗作用。方法:对诊刮确诊的17例子宫内膜癌病人,予丙氨瑞林700μg,im,qd×7d,用药前后作性激素测定及组织学检查。结果:绝经妇女用药后血中FSH和LH下降(P<0.01和<0.05),雌二醇、孕酮及睾丸酮变化不明显。其中13例内膜样腺癌用药后有丝分裂指数明显下降(P<0.01),有丝分裂指数变化与癌周内膜之反应有关。呈增生反应癌周内膜癌组织有丝分裂指数下降值明显高于呈萎缩状态癌周内膜。结论:丙氨瑞林治疗子宫内膜癌后能降低FSH和LH水平,对子宫内膜癌尤其是雌激素依赖性内膜癌有一定疗效。  相似文献   
59.
Consecutive male (n=100) and female (n= 100) DSM-IV schizophrenics newly registered for treatment in a large psychiatric hospital were examined with regard to age at onset of the first psychotic symptom. Age at onset of the first psychotic symptom did not differ between the sexes regardless of whether schizophrenia was diagnosed by DSM-IV or by several alternative systems. Age at onset defined by other criteria, namely age at first contact with a physician, and age at first admission for psychiatric care, also did not show any differences between the sexes. Survival analysis of subjects having a documented date of birth revealed a female preponderance at younger ages. A higher positive symptom score predicted older age at onset of the first psychotic symptom in the total sample. These findings call into question the universality of the traditional view of a younger age at onset of schizophrenia among males. Tentative neurodevelopmental and cultural explanations are presented to explain why there is no sex difference in age at onset of schizophrenia in India.  相似文献   
60.
This introduction traces the increasing awareness of the prevalence of child sexual abuse over the last 20 years, examines the nature and consequences of such abuse and summarizes current information on the use of group treatment and its evaluation with sexually abused children and adolescents and their parents. Four examples of group treatment with different populations of abused children are described in this issue.  相似文献   
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