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891.
Euy Kyun Shin Fumihiko Matsuda Junji Fujikura Takashi Akamizu Hideo Sugawa Toru Mori Tasuku Honjo 《European journal of immunology》1993,23(9):2365-2367
In an Epstein-Barr virus-transformed human B cell line we found an unusual immunoglobulin heavy chain gene rearrangement. Restriction mapping and sequencing analysis led us to conclude that VH-D and D-JH recombination took place in a single allele. Both VH-D and D-JH complexes still had their recombination signal sequences adjacent and the DNA sandwiched by these two complexes retained a germ line configuration, suggesting the potential for a secondary rearrangement resulting in a VH-D(-D)-JH formation. With this finding, we propose a novel pathway, in which the VH-D complex is an intermediate in the formation of a functional VH exon. 相似文献
892.
893.
Depression symptomatology was assessed up to four times at 2-year intervals on a sample of 2100 Danish twins initially aged 70 years and older. Data were analyzed using the biometric growth model approach proposed by Neale and McArdle (2000). Results show that occasion-specific depression is moderately and equally heritable in men and women (occasion-specific estimates of heritability ranged from 22% to 37%). Estimates of phenotypic variance, genetic variance, and heritability did not vary systematically across waves. In the best-fitting growth model, depression symptomatology was accounted for by two factors: (1) a level (i.e., average) effect that was highly heritable (estimate of 69% in women and 64% in men) and reflected overall vulnerability, and (2) a residual effect that was nonheritable and reflected occasion-specific circumstances that could either exacerbate or moderate inherited vulnerability. Attempts to identify specific genetic contributions to depression might profitably focus on average levels across multiple assessments, while attempts to identify specific environmental effects might profitably focus on deviations about this average. 相似文献
894.
895.
Larsen LA Svendsen IH Jensen AM Kanters JK Andersen PS Møller M Sørensen SA Sandøe E Jacobsen JR Vuust J Christiansen M 《Clinical genetics》2000,57(2):125-130
In a four-generation family with long QT syndrome, syncopes and torsades de pointes ventricular tachycardia (TdP) were elicited by abrupt awakening in the early morning hours. The syndrome was associated with a novel KCNH2 missense mutation, G572R, causing the substitution of a glycine residue at position 572, at the end of the S5 transmembrane segment of the HERG K(+)-channel, with an arginine residue. This segment is involved in the channel pore and the mutation may cause a reduction in the rapidly activating delayed rectifier K+ current (Ikr), or changed gating properties of the ion channel, leading to prolonged cardiac repolarization. The electrocardiograms of affected persons showed prolonged QT interval and notched T waves. Despite treatment with atenolol, 200 mg twice daily, the proband still experienced TdP episodes. Three untreated relatives of the proband died suddenly, and unexpectedly, at 18, 32, and 57 years of age. The G572R mutation is thus associated with a high mortality rate, and the clinical presentation illustrates that some mutations may not be controllable by just beta-blockade. 相似文献
896.
897.
Because prepared learning has been defined in terms of response acquisition in spite of degraded input, it was expected that differences in resistance to extinction between skin conductance responses conditioned to potentially phobic and neutral stimuli would increase with increased interstimulus interval (ISI) and be larger with a trace than with a delay conditioning paradigm. Twelve groups with 10 subjects each were observed in a differential conditioning experiment manipulating ISI (2, 8, or 16 sec), paradigm (delay versus trace), and fear-relevance of the conditioned stimulus (potentially phobic versus neutral). The results showed highly reliable resistance to extinction of first-interval anticipatory responses to phobic stimuli, and no resistance to extinction of the corresponding responses to the neutral stimuli. This difference did not interact either with the ISI or the paradigm factor. Thus, although underscoring the reliability of the difference in conditioning to potentially phobic and neutral stimuli, the results did not support the specific hypothesis of conditioning to phobic stimuli as being less dependent on the ISI parameters than conditioning to neutral stimuli. 相似文献
898.
A. V. Lagutin 《Bulletin of experimental biology and medicine》1977,84(3):1243-1246
Acute experiments were carried out on cats by a stereotaxic method to identify the morphological formations stimulation of which leads to the development of acute prolapse of the brain. These formations were found to be the lateral hypothalamic area, the zona incerta, zones H1 and H2, the parafascicular, interstitial, and interpeduncular nuclei, and the nucleus of Darkshevich. In response to stimulation of the lateral hypothalamic area, zona incerta, and zones H1 and H2, besides the characteristic histological changes of acute prolapse, signs of edema and swelling of the brain also were found.Department of Human Anatomy, Voroshilovgrad, Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. N. Chernigovskii.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 84, No. 9, pp. 276–279, September, 1977. 相似文献
899.
目的探讨重点理工科学校大一新生焦虑状况及相关因素,为进行针对性的干预提供依据。方法以广东某重点理工高校2007级的大一学生为研究对象,采用自行设计一般项目调查表、状态-特质焦虑量表(STAI)、匹兹堡睡眠质量指数量表(PSQI)、应付方式问卷进行测评。结果测查学生不论男女状态焦虑、特质焦虑分均显著高于地方常模;19.29%的学生睡眠质量较差;高状态焦虑组和高特质焦虑组解决问题、求助应付因子分均显著低于低状态焦虑组和低特质焦虑组,而自责、幻想、退避应付因子分则显著高于低状态焦虑组和低特质焦虑组;多元逐步回归分析说明,学生如常采用解决问题应付方式,在一定程度上可避免焦虑的产生,而睡眠质量差、采用自责应对方式则可加重焦虑水平。结论采取有效的认知应对策略其意义是使学生改变应激源,以使其变得威胁较小或变成挑战,把情绪基调训练成兴奋、期待和征服。 相似文献
900.
目的为探讨脑瘫在婴儿期的临床特征、早期发现、早期干预,以减少其后遗症的发生。方法将2005.06~2007.06在我院新生儿科住院的新生儿,NBNA评定总分≤35分者,分为干预组及对照组,干预组进行早期干预,观察两组高危因素、0—3个月出现早期症状、体征及后遗症方面有无明显差异,并随机收集无高危因素组为健康组,观察三组运动发育、姿势反射建立时间的差别。结果高危因素发生情况、0-3个月出现早期症状、体征方面,干预组与对照组无显著性差异,后遗症方面干预组1岁时无一例发生脑瘫,对照组1岁时有3例诊断为脑瘫,癫痫1例,脑积水1例,白内障1例,双侧神经性耳聋1例。结论早期干预,可降低脑瘫发生率,减轻脑瘫程度。对高危儿进行早期干预开始时间越早越好。 相似文献