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41.
目的研究1例散发多发性外生性骨疣患者的基因突变情况,确定其致病基因。方法采用聚合酶链反应结合DNA直接测序法检测EXT1以及EXT2基因的突变热点区域;并应用错配引物PCR扩增引入酶切位点结合限制性片段长度多态性方法检测和鉴定突变。结果经测序证实在患者EXT1基因的第7内含子3’剪接位点上游26bp处发现一杂合突变,此杂合突变不存在于其表型正常的父母双亲中,是一个新生突变;错配引物扩增与限制性片段长度多态性分析结果表明在150名家系外正常对照者中没有此突变。结论EXT1基因1633-26(C→A)突变可能是导致这个患者发生多发性外生性骨疣的致病突变。 相似文献
42.
43.
Dr. E. Carstens D. Klumpp M. Zimmermann 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1980,38(4):425-430
Summary Inhibition of spinal dorsal horn neuronal responses to noxious (50 °C) skin heating by stimulation of the midbrain periaqueductal gray (PAG) was quantitatively investigated in cats anesthetized with sodium pentobarbital and nitrous oxide. Systematic variation of the interval between onset of PAG stimulation (PAGS) and onset of noxious skin heating revealed that a marked reduction of spinal unit heat-evoked discharges occured immediately upon onset of PAGS, and ceased immediately at offset of PAGS with a post-stimulation excitatory rebound. Stimulation at sites in both ventral and dorsal PAG produced inhibition, the strength of which increased sometimes in a linear manner with increasing strength of PAGS. Thresholds for the generation of descending inhibition were higher in dorsal than ventral PAG. PAGS also inhibited spinal unit responses to non-noxious skin stimulation (brushing of hairs). Descending inhibition from PAG is considered as a possible mechanism for analgesia produced by stimulation of PAG and other brainstem structures.The work was supported by a grant from the Deutsche Forschungsgemeinschaft (Zi 110) 相似文献
44.
在急性分离的大鼠骶髓后连合核神经元上,采用制霉菌素穿孔法膜片钳技术,研究AMPA受体和NMDA受体的相互作用.结果显示,激活AMPA受体可逆性地抑制NMDA反应,该效应依赖于细胞外钙离子.而且,通过AMPA受体通道内流的钙离子单独即足以抑制NMDA受体介导的反应.本结果证明,钙离子可透性AMPA受体可能参与了脊髓伤害性信息的调控.该过程可能与针刺镇痛的机制有关. 相似文献
45.
Christoph Wiegreffe Bodo Christ Ruijin Huang Martin Scaal 《Developmental dynamics》2007,236(9):2578-2585
The dorsal aorta is the earliest formed intraembryonic blood vessel. It is composed of an inner lining consisting of endothelial cells and an outer wall consisting of smooth muscle cells (SMCs) and fibrocytes. Aortic SMCs have been suggested to arise from several developmental lineages. Cephalic neural crest provides SMCs of the proximal part of the aorta, and SMCs of the distal part are derived from the paraxial mesoderm. Here, we show by using quail-chick chimerization that in the avian embryo, SMCs in the wall of the dorsal aorta at trunk level arise from the sclerotome. Our findings indicate a two-step process of aortic wall formation. First, non-paraxial mesoderm-derived mural cells accumulate at the floor of the aorta. We refer to these cells as primary SMCs. Second, SMCs from the sclerotome are recruited to the roof and sides of the aorta, eventually replacing the primary SMCs in the aortic floor. 相似文献
46.
目的:探讨指背腱膜滑动距离与近侧指间关节(PIP)屈曲关系,为临床修复提供解剖学基础。方法:男性成人新鲜尸体标本10侧30指(示、中、环指各10指),切除手指皮肤,不破坏腱鞘、屈肌支持带、伸肌支持带、内在肌及外在肌,使肌腱保持正常的生理状态,分别测量各指中央束(CS)、侧束(LB)在PIP屈曲45°和90°时的滑动距离。结果:当PIP屈曲45°时,CS滑动距离为(2.7±0.4)mm,LB滑动距离为(2.8±0.6)mm;当PIP屈曲90°时,CS滑动距离为(4.3±0.7)mm,LB滑动距离为(4.8±0.6)mm。结论:指背腱膜滑动距离减少,严重影响手指的屈曲功能。对于指背腱膜的新鲜性损伤应予以精确修复;对于陈旧性损伤的修复应确保指背腱膜的正常滑动范围。 相似文献
47.
本文应用放射免疫分析方法,测定了16只哮喘豚鼠初级传入系统和中枢内神经激肽β(NKB)的水平。结果表明,与正常对照组(结状神经书3228±11.89,C7~C8段脊神经节23.63±13.26,T1~T2段脊神经节24.25±1819,T3~T5段脊神经节25.53±12.34,C7~T5段脊髓后角28.65±16.59,孤束核26.34±18.36Pg/gwettissue)相比较,哮喘豚鼠初级传入系统和中枢内(结状神经节43.26±12.35,C7~C段脊神经节32.53±17.63,T1~T2段神经书32.25±20.65,T3~T5段脊神经节34.36±15.33,C7~T5段脊髓后角39.53±2028,孤束核3662±17.85Pg/gwettissue)NKB的含量明显高于对照组(P<0.05)。结合NKB在呼吸道的作用,这些结果提示,初级传入系统和中枢内的NKB可能参与哮喘发病的病理生理机制。 相似文献
48.
Cortical and sub-cortical lesions in the rat were used to analyze the intracortical trajectory of the noradrenergic axons, which were visualized by aldehyde-induced catecholamine histofluorescence and by immunohistochemistry using an antibody directed against rat dopamine-β-hydroxylase. Following subcortical lesions there is a slowly progressive reduction in the density of cortical noradrenergic axons, indicating that they undergo asynchronous anterograde degeneration. By 2 weeks after transection of the dorsal noradrenergic bundle, no dopamine β-hydroxylase-immunoreactive fibers are detectable in the ipsilateral cortex. Neither transection of the cingulum bundle, nor parasagittal incisions through the dorsal cortex lateral to the cingulum, diminished the noradrenergic innervation of medial or dorso-lateral cortex. A cortical lesion medial to the cingulum bundle markedly reduced the density of noradrenergic fibers in cingulate cortex caudal to the lesion, but did not affect the innervation of dorso-lateral cortex. In contrast, dorso-lateral frontal incisions and decortication (frontal lobotomy) produced a marked ipsilateral decrease in the noradrenergic fiber density throughout the remaining dorso-lateral cortex, while sparing the innervation of cingulate and infra-rhinal cortex.These results demonstrate that the dorso-lateral cortex is innervated by noradrenergic fibers in the medial forebrain bundle that reach the frontal pole, turn dorsally over the anterior portion of the forceps minor and continue caudally within the deep layers of frontal and dorso-lateral cortex, supplying the noradrenergic innervation throughout their trajectory. The medial cortex is innervated by a separate group of noradrenergic fibers that ascend through the septum, curve over the genu of the corpus callosum, and run caudally in the supracallosal stria.The present results show that the cingulum bundle is not a major intra-cortical noradrenergic pathway and does not provide branches that contribute significantly to the innervation of dorsal or lateral cortex. Thus the medial and lateral cortex can be selectively and differentially denervated of noradrenergic fibers and a coarse topographic order exists in the noradrenergic innervation of cortex. Since noradrenergic fibers travel long distances within the cortical grey matter, a small lesion of frontal cortex can have far-reaching effects on the innervation of distant, more caudal regions of cortex. The coeruleocortical projection has properties that differ from those of the best characterized cortical afferents and may be a useful model for the study of other ascending monoamine systems. The tangential, intracortical trajectory of the noradrenergic fibers would confer upon the coeruleo-cortical system the capacity to modulate neuronal activity simultaneously through a vast expanse of neocortex. A formulation of cortical organization is presented which integrates the tangential organization of the coeruleo-cortical projection with the concept of columnar organization of cortex. 相似文献
49.
目的:为桡骨交锁髓内钉固定术避免桡神经深支损伤提供解剖学依据。方法:前臂标本44侧解剖显露桡神经深支,将肱骨外上髁与Lister结节连线和桡骨头关节面,关节面下1.0、1.5、2.0cm,桡神经深支穿入旋后肌平面,桡神经深支跨越桡骨平面等6个面的交点,依次标记为A、B、C、D、E、F6个点。记录AE、AF的长度,测量B、C、D3个定点在屈肘前臂旋前、中立、旋后位与桡神经深支的水平距离。结果:B、C、D3个定点离桡神经深支的距离越来越近;而对于同一定点,其与桡神经深支的距离按旋前、中立、旋后位的顺序越来越远。结论:桡骨交锁髓内钉固定时,宜于屈肘前臂中立位,在肱骨外上髁与Lister结节连线上,距桡骨头关节面约1.5cm的位置,由前臂后外侧向前内侧插入远端交锁螺丝钉较为安全。 相似文献
50.
目的:为设计阴部外动脉阴茎皮瓣转位尿道成形术提供依据。方法:30侧经动脉内灌注红色乳胶的成人尸体,解剖观测阴部外动脉起始、行程;着重阴部外动脉阴茎支在阴茎的走行、分支分布。结果:阴部外动脉始于股动脉,外径1.8±0.4mm,伴行静脉1-2支,汇入大隐静脉。阴茎支可视为本干的延续,经耻骨结节两侧靠近阴茎,分别经2(10)点、3(9)点和1(11)点进入阴茎,多数分出背侧支、腹侧支分布阴茎皮肤。外径0.8±0.2mm。结论:阴茎皮肤血管恒定,以阴茎支为蒂,可在阴茎外侧或背外侧、腹外侧设计皮瓣,用于尿道成形术。术式已在临床应用,效果满意。 相似文献