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排序方式: 共有591条查询结果,搜索用时 15 毫秒
21.
Characterization of de novo microdeletions involving 17q11.2q12 identified through chromosomal comparative genomic hybridization 总被引:1,自引:0,他引:1
Brunetti-Pierri N Grange DK Ou Z Peiffer DA Peacock SK Cooper ML Eng PA Lalani SR Chinault AC Gunderson KL Craigen WJ Cheung SW 《Clinical genetics》2007,72(5):411-419
High-resolution array-comparative genome hybridization (CGH) is a powerful tool for detection of submicroscopic chromosome deletions and duplications. We describe two patients with mild mental retardation (MR) and de novo microdeletions of 17q11.2q12. Although the deletions did not involve the neurofibromatosis type 1 (NF1) gene, they overlap with long-range deletions of the NF1 region which have been encountered in a small group of NF1 patients with more severe MR. Given the overlap of the deletions in our two patients with the large-sized NF1 microdeletions but not with the more frequent and smaller NF1 deletions, we hypothesize that more than one gene in the 17q11.2q12 region may be involved in MR. We discuss candidate genes for MR within this interval that was precisely defined through array-CGH analysis. 相似文献
22.
功能性胃肠病的根源——脑肠轴神经系统记忆假说 总被引:7,自引:0,他引:7
功能性胃肠病(functionalgastrointestinaldisorders,FGID)以消化道动力与内脏感觉异常为主要病理生理特征并有多种症状重叠、多变或相互转换以及反复发作、较难治愈等特点;其病因和发病机制目前仍未完全清楚.本文将大脑记忆外延提出FGID的根源是脑肠轴神经系统记忆的假说,并用这个假说解释说明FGID的各种特点,以及治疗FGID的思路和方法. 相似文献
23.
24.
腺苷三磷酸结合盒转运蛋白A1在动脉粥样硬化中的作用及其受控特点 总被引:4,自引:0,他引:4
目的:分析腺苷三磷酸结合盒转运蛋白A1(ATP binding cassette transport proteion A1,ABCA1)在动脉粥样硬化中的作用及其受控机制。资料来源:以“腺苷三磷酸结合盒转运蛋白A1”为检索词,应用计算机在Pubmed、中文全文数据库CNKI中检索2000-01/2006-11腺苷三磷酸结合盒转运蛋白A1与人有关的期刊文献,前者限定语言种类为英文,后者限定语言种类为中文。资料选择:对英文文献390篇、中文文献58篇初审。纳入标准:①与ABCA1结构及功能有关的文献。②与核受体有关的文献。③与载脂蛋白AⅠ有关的文献。④与ABCA1基因的突变、单核苷酸多态性有关的文献。⑤ABCA1蛋白、核受体、ABCA1基因的突变、单核苷酸多态性与动脉粥样硬化有关的文献。排出标准:①与哮喘、癌症、代谢性疾病有关的文献。②相关文献中内容相似的文献。③综述文献。资料提炼:选取3篇涉及ABCA1结构、功能的基础内容;18篇涉及与核受体的内容;2篇涉及载脂蛋白AⅠ的内容;7篇涉及ABCA1基因的突变、单核苷酸多态性的内容;9篇涉及ABCA1蛋白、核受体、ABCA1基因的突变、单核苷酸与动脉粥样硬化的内容。其中30篇列为参考文献。资料综合:分析了腺苷三磷酸结合盒转运体A1的结构和功能的基本情况;文献显示腺苷三磷酸结合盒转运体A1在动脉粥样硬化发病过程中起重要作用;核受体对腺苷三磷酸结合盒转运体A1的表达有调节,且腺苷三磷酸结合盒转运体A1受基因调控。结论:腺苷三磷酸结合盒转运体A1可能是与动脉粥样硬化密切相关的重要候选基因;深入探讨其机制,有利于开发新药防治动脉粥样硬化。 相似文献
25.
Ageing appearance in China: biophysical profile of facial skin and its relationship to perceived age
AE Mayes PG Murray DA Gunn CC Tomlin SD Catt YB Wen LP Zhou HQ Wang M Catt SP Granger 《Journal of the European Academy of Dermatology and Venereology》2010,24(3):341-348
Background Perceived age is important to women and is a primary driver for topical product use and facial cosmetic surgery. Changes in facial features and biophysical skin parameters with chronological age and their associations with perceived age have not been described in Asian populations. Objective To investigate the relationship between biophysical properties of the skin, visual features of skin ageing and perceived facial age in Chinese women. Methods Facial photographs were collected of 250 Chinese women, aged 25–70 years in Shanghai, China. The perceived facial age was determined and related to the chronological age for each participant and to a range of visual assessments of skin appearance and objective biophysical measurements of the skin. The profile of changes in these parameters with age was investigated together with the differences in those parameters for women judged to look younger than their chronological age and those judged to look older than their chronological age. Results Large discrepancies in perceived age (up to 29 years) were found in women of the same chronological age. Each objective skin measure and visual assessment parameter had a stronger correlation with perceived age than with chronological age. The strongest relationships to perceived age were for wrinkles and hyperpigmentation. Skin colour, hydration and trans‐epidermal water loss (TEWL) had weaker associations with perceived age. Women judged to look older than their chronological age had significantly higher scores than those judged to look younger for coarse wrinkles and hyperpigmentation across all age groups. The appearance differences between these groups were evident in composite facial images of the same average chronological age. Conclusions We have identified the skin attributes which differ with perceived age in Chinese women. Perceived age is a better measure of the biological age of facial skin than is chronological age in this population. 相似文献
26.
We present an anonymous questionnaire inquiry involving 334 primary schoolteachers in the Randers area with the purpose of elucidating teachers' knowledge about asthma. To a series of statements about asthma, the teachers answered yes, no or don't know. A limited knowledge of different aspects of asthma in children was found, although 57% had asthma children in their classes. Specially limited was knowledge about medical treatment. Five percent had received proper instruction about asthma and had a significantly better knowledge of medical treatment (p less than 0.001-0.05). Only 57% knew that wheezing after physical exertion is a strong indicator of asthma and only 33% knew that exertion in cold weather increases the risk of an attack. It is recommended that instruction in children's diseases, especially asthma, is introduced in teacher training colleges. 相似文献
27.
Further evidence for the role of genes on chromosome 2 and chromosome 5 in the inheritance of pulmonary function 总被引:3,自引:0,他引:3
Malhotra A Peiffer AP Ryujin DT Elsner T Kanner RE Leppert MF Hasstedt SJ 《American journal of respiratory and critical care medicine》2003,168(5):556-561
The spirometric measurements FEV1, FVC, and the ratio FEV1/FVC are used in the diagnosis of lung function disorders. Therefore, understanding the genetics underlying these spirometric measurements will increase our knowledge of the genetics of pulmonary function. FEV1 and FVC were measured on 264 members of 26 Utah Genetic Reference pedigrees, originally collected for the Centre d'Etude du Polymorphisme Humain genetic mapping project. Using segregation analysis, we inferred major locus inheritance of the FEV1/FVC ratio, although we could not distinguish between a dominant or recessive mode of inheritance. No evidence of major locus inheritance was found for either FEV1 or FVC. Suggestive evidence of linkage for the ratio FEV1/FVC was found on chromosome 2 (heterogeneity lod = 2.36, dominant model) and chromosome 5 (heterogeneity lod = 2.23, recessive model), replicating linkages from other studies. In addition, nonparametric variance component linkage analysis showed linkage of FEV1/FVC in both of these regions, providing further support to the results. No nonparametric lod scores over 1.5 were obtained for either FEV1 or FVC. 相似文献
28.
Hypoplasia ponto-neocerebellaris 总被引:1,自引:0,他引:1
Zusammenfassung Anhand der klinischen Beobachtung von drei Geschwisterkindern, von denen eines auch pathologisch-anatomisch untersucht werden konnte, wird das Bild der Hypoplasia ponto-neocerebellaris in Erinnerung gerufen und differentialdiagnostisch von der Nyssen-van Bogaert'schen Dégénérescence optico-cochléo-dentelée abgegrenzt. Charakteristische morphologische Zeichen sind die Aufgliederung des Dentatumzellbandes in zahlreiche kleine Zellinseln, die Verschmächtigung des Brückenfußes und eine mangelhafte Fältelung des Oliven-Zellbandes.
Summary In an otherwise healthy family three male infants fell ill with microcephaly, hypotonus of the muscles, non-specific hyperkineses, seizures, and rapid mental deterioration. In addition to microdysplasia in the cerebral cortex the main neuropathological findings were the separation of the dentate nucleus into many islets, an atypical band of the inferior olives, and deficiency of the pontocerebellar fibers in the basal part of the pons. The hypoplasia of the areas involved can be distinguished from the degenerative process in the dégénérescence systematisé optico-cochleo-dentelé (Nyssen-van Bogaert).相似文献
29.
While portable spirometers are increasingly used, little attention has been paid to test their validity for measurement of flows in small airways. The aim of this study was to compare the Spirotel portable spirometer to a laboratory spirometer (Jeager PFT), with regard to accuracy in measuring forced expiratory flows, and more specifically those influenced by small airways (FEF(25-75)). Fifty-nine children (mean age, 12 years; range, 7-17), were studied at baseline and after a bronchodilator inhalation. Spirometers were tested separately in a randomly designed order. A total of 117 sessions of flow-volume curves was performed with each spirometer. We obtained at least two acceptable and reproducible curves in 88% and 76% of the sessions, with the laboratory and the portable spirometers, respectively. Unacceptable curves were easily detected by visual inspection of flow-time and flow-volume waveforms. Agreement was excellent between spirometers for the measurement of all expiratory flows, both at baseline and postbronchodilator. More specifically, agreement between spirometers was as high for measurements of FEF(25-75) (intraclass correlation coefficients 0.97) as for proximal flows. High correlations were found between baseline expiratory flows measured by each spirometer (and expressed as percent of predicted values), both in large and small airways (P < 0.001). The portable spirometer was highly sensitive for detecting small airways obstruction, as compared to the laboratory spirometer. Finally, the magnitudes of bronchodilator-related flow changes were also highly correlated, both in large and small airways (P < 0.001 and P = 0.004, respectively). We conclude that the Spirotel portable spirometer is reliable for measurement of forced expiratory flows, in large and small airways, provided that all curve waveforms can be stored and available for visual inspection. 相似文献
30.
Data from rodent models of induced microgyria suggest that bilateral damage leads to more severe rapid auditory processing deficits than unilateral damage. It is unclear whether this reflects the degree, or bilateral/unilateral nature, of damage. The current study evaluates the effects of microgyric severity by assessing rats with single- vs double-pair bilateral focal microgyric lesions, using auditory discrimination and MGN measures. Behavioral data show a significant auditory processing deficit on rapid processing tasks for microgyric as compared to control subjects, and also reveal more severe deficits for double- than for single-pair bilateral microgyrics. Greater disruptions are also seen in the MGN of double-pair compared to single-pair bilateral microgyric subjects. 相似文献