排序方式: 共有15条查询结果,搜索用时 31 毫秒
11.
Kopp P 《Cellular and molecular life sciences : CMLS》2001,58(9):1301-1322
The thyrotropin (TSH) receptor plays a preeminent role in thyroid physiology and disease. TSH, acting through the TSH receptor,
is the major stimulator of thyroid cell growth, differentiation and function. In Graves' disease, the TSH receptor is the
target of stimulating antibodies that cause hyperthyroidism. Although still a topic of debate, the TSH receptor has been implicated
in the pathogenesis of the endocrine ophthalmopathy associated with Graves' disease. Blocking antibodies against the TSH receptor
are involved in the development of hypothyroidism in a subset of patients with autoimmune hypothyroidism. Transplacental passage
of stimulating or blocking TSH receptor antibodies from a mother with autoimmune thyroid disease may result in transient hyper-
or hypothyroidism in early infancy. During pregnancy, the placental hormone human choriogonadotropin (hCG) can cause gestational
hyperthyroidism through cross-reaction with the TSH receptor. Gestational hyperthyroidism may also be involved in the pathogenesis
of hyperemesis gravidarum. Trophoblast tumors secreting hCG are a rare cause of hyperthyroidism. Somatic activating mutations
of the TSH receptor have been identified as a molecular cause of toxic adenomas, whereas activating mutations in the germline
give rise to nonautoimmune familial hyperthyroidism or sporadic congenital hyperthyroidism. These gain-of-function mutations
are dominant, and one mutated allele is sufficient to result in disease. Inactivating germline mutations of both TSH receptor
alleles lead to variable degrees of resistance to TSH, encompassing a spectrum ranging from euthyroid hyperthyrotropinemia
to overt hypothyroidism with thyroid hypoplasia.
Received 31 January 2001; received after revision 3 April 2001; accepted 3 April 2001 相似文献
12.
Sexually dimorphic abdominal pigmentation and segment morphology evolved recently in the melanogaster species group of the fruitfly Drosophila. Here we show that these traits are controlled by the bric à brac [corrected] (bab) gene, which integrates regulatory inputs from the homeotic and sex-determination pathways. bab expression is modulated segment- and sex-specifically in sexually dimorphic species, but is uniform in sexually monomorphic species. We suggest that bab has an ancestral homeotic function, and that regulatory changes at the bab locus played a key role in the evolution of sexual dimorphism. Pigmentation patterns specified by bab affect mating preferences, suggesting that sexual selection has contributed to the evolution of bab regulation. 相似文献
13.
研究了带有时变时滞的中立型随机系统的鲁棒镇定和H∞控制问题.利用Lyapunov泛函方法和It o^公式,基于状态反馈控制器,以线性矩阵不等式(LMI)形式给出了闭环系统鲁棒镇定及H∞控制的新方法.最后,数值算例说明了该方法的有效性. 相似文献
14.
论竞技健美操技术创新的概念与分类 总被引:1,自引:0,他引:1
任蓓 《重庆工商大学学报(自然科学版)》2009,26(2):203-208
该研究以竞技健美操技术创新为研究对象,采用文献资料法、案例分析法,对查阅的文献和案例进行综合的归纳分析,在研究竞技健美操技术创新发展现状基础上,结合其他项目技术创新的特点,对竞技健美操技术创新的概念进行了阐述;对竞技健美操技术创新进行了系统的分类. 相似文献
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