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31.
32.
Trends in pubertal development in Europe 总被引:8,自引:0,他引:8
The secular changes in growth and maturation can be seen as indicators of socio-economic and health status. In most European countries the age of onset of puberty and of menarcheal age has been decreasing during the past few decades. The duration of puberty seems also to decrease, though few studies provide sufficient data to support this postulation. The four Dutch nationwide growth surveys are useful examples assessing the secular trend in pubertal development over the past 45 years. Genetic and environmental factors contribute to the secular changes. Environmental factors seem to be the most important. Recently, attention has been given to substances with oestrogen-like actions that are present in nutrients. The possible role of these substances in growth and maturation is discussed. 相似文献
33.
成人小脑髓母细胞瘤的临床及病理研究 总被引:4,自引:0,他引:4
目的探讨成人小脑髓母细胞瘤的临床病理特点、组织发生学及影响预后的因素。方法对我院1974~1995年间27例成年人(≥16岁)小脑髓母细胞瘤进行了观察。结果本组年龄16~55岁,平均25.8岁,肿瘤发生于小脑蚓部21例,小脑半球6例。随访21例,7例已生存2.5~17年,14例死亡。平均生存时间41.6个月。1年生存率为71.4%,5年及10年生存率均14.3%。组织学类型:经典型14例,促纤维增生型13例。结论通过电镜观察及突触素、神经元特异性烯醇化酶和胶质纤维酸性蛋白免疫组化染色观察,证实髓母细胞瘤是具有向神经元及胶质细胞双向分化潜能的原始神经外胚叶肿瘤。影响预后的因素包括年龄、肿瘤部位、治疗手段以及组织学类型 相似文献
34.
Age of onset in Huntington disease: sex specific influence of apolipoprotein E genotype and normal CAG repeat length 总被引:8,自引:0,他引:8 下载免费PDF全文
Age of onset (AO) of Huntington disease (HD) is known to be correlated with the length of an expanded CAG repeat in the HD gene. Apolipoprotein E (APOE) genotype, in turn, is known to influence AO in Alzheimer disease, rendering the APOE gene a likely candidate to affect AO in other neurological diseases too. We therefore determined APOE genotype and normal CAG repeat length in the HD gene for 138 HD patients who were previously analysed with respect to CAG repeat length. Genotyping for APOE was performed blind to clinical information. In addition to highlighting the effect of the normal repeat length upon AO in maternally inherited HD and in male patients, we show that the APOE epsilon2epsilon3 genotype is associated with significantly earlier AO in males than in females. Such a sex difference in AO was not apparent for any of the other APOE genotypes. Our findings suggest that subtle differences in the course of the neurodegeneration in HD may allow interacting genes to exert gender specific effects upon AO. 相似文献
35.
Chiara Fenoglio Daniela Galimberti Laura Piccio Diego Scalabrini Paola Panina Cecilia Buonsanti Eliana Venturelli Carlo Lovati Gianluigi Forloni Claudio Mariani Nereo Bresolin Elio Scarpini 《Neuroscience letters》2007
Triggering Receptor Expressed on Myeloid cells (TREM)2 deficiency originates a genetic syndrome characterized by bone cysts and presenile dementia, named Nasu-Hakola disease (NHD). Early onset dementia and marked involvement of frontal regions are features characterizing both NHD and other kinds of neurodegenerative disorders, such as Frontotemporal Lobar Degeneration (FTLD), and, in some cases, Alzheimer's disease (AD). Three Single Nucleotide Polymorphisms (SNPs) in TREM2 coding region were screened by allelic discrimination in a population of probable AD patients as well as FTLD patients as compared with age-matched controls. In addition, mutation scanning of the coding region of TREM2 gene was carried out in 7 patients with early onset AD (EOAD), 16 FTLD, and 20 controls. None of the SNPs analyzed was present, either in patients or controls. Moreover, mutation scanning of the five exons of TREM2 failed to detect the presence of novel polymorphisms. These data demonstrate that TREM2 coding region is highly conserved, implying a crucial role of this receptor. Further studies, including a functional analysis, are certainly required to clarify the role of TREM2 in neurodegenerative processes. 相似文献
36.
Kiyoshi Takahashi Naorni Sakashita Yukio Ando Moritaka Suga Masayukl Ando 《Pathology international》1997,47(6):353-359
Clinicopathological features of three autopsy cases of extremely rare late onset type I familial amyloldotic polyneuropathy were presented and compared with 19 autopsy cases of the ordinary type. In the late onset cases, the ages at onset and at death were 27.5 and 24.5 years older, respectively, compared with the ordinary type. Also, duration of the total clinical course form onset to death was 3.7 years less than in the late onset cases. The degree of amyloid deposition was more marked in the heart of the late onset cases, causing prominent cardiac hypertrophy. It was also marked In the kidneys or thyroid of two cases, but slight to moderate in the peripheral or autonomic nervous tissues in all cases. Immunohistochemical Investigation demonstrated the presence of transthyretin (TTR) as an amyloid precursor protein and of serum amyloid P-component in amyloid deposits in various organs and tissues of the late onset type. These findings, as well as serum levels of variant TTR, were similar to those of the ordinary type. These results suggest that there are some factors other than the amyloid precursor protein that effect the degree of amyloid deposition. 相似文献
37.
Electrodermal Orienting Responses to Onset and Offset of Auditory Stimulation under Nonsignal Conditions 总被引:1,自引:0,他引:1
It has previously been reported that the orienting reflex (OR) to the onset of a stimulus habituates more slowly than the OR to stimulus offset. In this paper, we attempted to account for this in terms of differences between the ON condition (whose presentation elicits the onset OR) and the OFF condition (whose “presentation” elicits the offset OR). Because the typical habituation paradigm begins with a period of adaptation to the OFF (stimulus absent) condition, the relative novelty of the ON condition is enhanced. This bias would contribute to the advantage of onset ORs over offset responses. This hypothesis was evaluated by comparing skin conductance responses (SCRs) to onset and offset of a 600 Hz tone in a group adapted in the presence of that tone (Tone Adaptation, TA) vs one adapted in its absence (Silent Adaptation, SA). The results supported our hypothesis; onset ORs habituated significantly more slowly than offset ORs in Group SA, but not in Group TA. 相似文献
38.
Evidence for an Association of the Dopamine D5 Receptor Gene on Age at Onset of Attention Deficit Hyperactivity Disorder 总被引:3,自引:0,他引:3
J. Lasky-Su J. Biederman N. Laird M. Tsuang A. E. Doyle J. W. Smoller C. Lange S. V. Faraone 《Annals of human genetics》2007,71(5):648-659
The purpose of this study was to determine whether the single nucleotide polymorphisms (SNPs) within candidate genes for attention deficit hyperactivity disorder (ADHD) are associated with the age at onset for ADHD. One hundred and forty-three SNPs were genotyped across five candidate genes ( DRD5 , SLC6A3 , HTR1B , SNAP25 , DRD4 ) for ADHD in 229 families with at least one affected offspring. SNPs with the highest estimated power to detect an association with age at onset were selected for each candidate gene, using a power-based screening procedure that does not compromise the nominal significance level. A time-to-onset analysis for family-based samples was performed on these SNPs to determine if an association exists with age at onset for ADHD. Seven consecutive SNPs surrounding the D5 dopamine receptor gene ( DRD5 ), were associated with the age at onset for ADHD; FDR adjusted q-values ranged from 0.008 to 0.023. This analysis indicates that individuals with the risk genotype develop ADHD earlier than individuals with any other genotype. A haplotype analysis across the 6 significant SNPs that were in linkage disequilibrium with one another, CTCATA , was also found to be significant (p-value = 0.02). We did not observe significant associations with age at onset for the other candidate loci tested. Although definitive conclusions await independent replication, these results suggest that a variant in DRD5 may affect age at onset for ADHD. 相似文献
39.
《Disability and health journal》2021,14(4):101122
BackgroundDisability faced by a young person can impact the school-to-work transition and shape health and well-being over the life course. Unique barriers to entry and advancement within the labor market that are relevant to young people with disabilities underscore the need for tailored policy-level supports.ObjectivesTo examine and describe policies that support the school-to-work transition of young people with disabilities in Canada.MethodsA scan of policies which focused on the school-to-work transition of young people with disabilities across Canada was conducted between June 2019 and January 2020. Searches were completed within federal, provincial and territorial policy portals. Each policy relating to employment participation of people with disabilities was summarized. Policies that focused on the school-to-work-specific were synthesized using Bemelmans-Vidic, Rist and Vedung's policy tool framework.ResultsA total of 36 policies were identified by our scan that focused on the employment of people with disabilities. Only five policies explicitly addressed the school-to-work transition. All existing policies were implemented at the provincial level and aimed to promote entry into employment. The synthesis of policies revealed that financial policy tools were primarily used to incentivize employment, provision of workplace accommodations, or the development and implementation of job readiness programs.ConclusionOur analysis of federal, provincial and territorial policies in Canada uncovered a limited number of policies that specifically support the school-to-work transition. Addressing these policy gaps can increase the inclusion of young people with disabilities in the labor market. 相似文献
40.
ObjectivesThe aim of this study was to investigate the impact of mixed cognitive intervention training using spaced retrieval training, and errorless learning in participants with early onset dementia. This was based on reality orientation therapy for cognitive function, depression, and occupational performance of patients.MethodsTwo early onset vascular dementia patients (> 65 years) with mild or moderate impairment were enrolled in a pre-test - post-test single-subject research design study. Prior to the study, the caregivers were interviewed about meaningful times, people, places, and areas of interest for the participant. A list of individual training words were selected based upon this information, and the participant was instructed to recall them after a 45-second, 90-second, 6-minute, and 12-minute delay. Baseline (3 sessions), intervention (20 sessions), and a second baseline period (3 sessions) were conducted. Activities of daily living were measured, and cognition was measured using the Consortium to Establish a Registry of Alzheimer’s Disease Korean version, whilst depression was measured using the Korean Form Geriatric Depression Scale, and task performance and satisfaction measured by the Canadian Occupational Performance Measure.ResultsAfter intervention, both participants showed improvements in activities of daily living (ADL), word list memory/recognition, trail making A, occupational performance, and satisfaction improvement, which was clinically significant in 1 participant who also had a reduced score in the scale of depression classifying him as not depressed.ConclusionSpaced retrieval training and errorless learning based on reality orientation therapy is an effective intervention in patients with early onset dementia and mild or moderate impairment. 相似文献