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11.
目的 制备具有天然神经组织结构的支架,构建组织工程化面神经用于修复面神经损伤。方法 取家兔面神经,改良化学萃取法制备脱细胞神经基质,HE染色形态学观察去细胞及脱髓鞘情况,荧光分光光度计测定支架内细胞经Quant-iT PicoGreen工作液染色后的DNA含量。MTT法检测细胞在支架上的相对生长率从而检测支架的细胞毒性。结果 支架移植体呈圆柱形,弹性与正常神经基本一致,组织观察显示细胞结构未见残余完整细胞及细胞碎片残留,未见神经髓鞘及轴突结构,细胞外基质形成纵向排列结构,结构之间可见空隙。兔脱细胞面神经基质支架内残留的DNA含量较正常兔面神经明显下降(P<0.01)。神经基质供体无细胞毒性。结论 改良化学萃取法可有效去除面神经细胞,天然结构保存完好,细胞毒性低,可作为组织工程化面神经的支架。  相似文献   
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Hereditary neuropathy with liability to pressure palsies (HNPP; also called tomaculous neuropathy) is an autosomal-dominant disorder that produces a painless episodic, recurrent, focal demyelinating neuropathy. HNPP generally develops during adolescence, and may cause attacks of numbness, muscular weakness, and atrophy. Peroneal palsies, carpal tunnel syndrome, and other entrapment neuropathies may be frequent manifestations of HNPP. Motor and sensory nerve conduction velocities may be reduced in clinically affected patients, as well as in asymptomatic gene carriers. The histopathological changes observed in peripheral nerves of HNPP patients include segmental demyelination and tomaculous or “sausage-like” formations. Mild overlap of clinical features with Charcot-Marie-Tooth (CMT) disease type 1 (CMT1) may lead patients with HNPP to be misdiagnosed as having CMT1. HNPP and CMT1 are both demyelinating neuropathies, however, their clinical, pathological, and electrophysiological features are quite distinct. HNPP is most frequently associated with a 1.4-Mb pair deletion on chromosome 17p12. A duplication of the identical region leads to CMT1A. Both HNPP and CMT1A result from a dosage effect of the PMP22 gene, which is contained within the deleted/duplicated region. This is reflected in reduced mRNA and protein levels in sural nerve biopsy samples from HNPP patients. Treatment for HNPP consists of preventative and symptom-easing measures. Hereditary neuralgic amyotrophy (HNA; also called familial brachial plexus neuropathy) is an autosomal-dominant disorder causing episodes of paralysis and muscle weakness initiated by severe pain. Individuals with HNA may suffer repeated episodes of intense pain, paralysis, and sensory disturbances in an affected limb. The onset of HNA is at birth or later in childhood with prognosis for recovery usually favorable; however, persons with HNA may have permanent residual neurological dysfunction following attack(s). Episodes are often triggered by infections, immunizations, the puerperium, and stress. Electrophysiological studies show normal or mildly prolonged motor nerve conduction velocities distal to the affected brachial plexus. Pathological studies have found axonal degeneration in nerves examined distal to the plexus abnormality. In some HNA pedigrees there are characteristic facial features, including hypotelorism. The prognosis for recovery of normal function of affected limbs in HNA is good, although recurrent episodes may cause residual deficits. HNA is genetically linked to chromosome 17q25, where mutations in the septin-9 (SEPT9) gene have been found.  相似文献   
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This article describes the association between previous infection and/or vaccination and the development of optic neuritis (ON) in 18 children. Ten of these children subsequently developed clinically definite multiple sclerosis (MS), while in 8 patients a clinically definite etiology could not be confirmed. Vaccination preceded the first ON attack in 6 patients, all but one of whom subsequently developed MS. It also preceded subsequent demyelinating events in 6 patients. Ten of the patients had a bacterial or viral infection within the 2 weeks prior to the first symptoms of ON. Intrathecal antibody synthesis against 2 or more viruses could be shown in 5 out of 8 patients studied; 5 out of 6 patients had oligoclonal antibodies in CSF and 12 out of 16 patients a high IgG index. Neither intrathecal antibody synthesis against 2 or more viruses nor elevated IgG indexes could be found in the control patients. Measles and mumps occurred at a significantly later age in the children who subsequently developed MS than in the control children, and these patients had significantly more events that might have impaired the blood-brain barrier than the controls. These results indicate that immunological events leading to MS may be triggered during childhood. Vaccination and infection often precede ON in childhood. Intrathecal viral antibody production can occur already in childhood at the time of the first symptoms of MS.  相似文献   
15.
Age determines memory for face identity and expression   总被引:1,自引:1,他引:0  
Background: The recognition of facial expressions is an important component of emotion processing which contributes to interactional behavior. One of the factors highly associated with potential decline of ability in behavioral tasks is age. Methods: We have investigated age‐related changes in facial identity and expression memory of healthy subjects in three age groups: young adults (20–40 years), elderly adults (60–80 years) and, for the first time in the literature, very old adults (over 80 years of age). Using a picture test, photographs of faces with happy or angry expressions were presented to study participants during the encoding task, and the memory for identity and emotional facial expression was investigated in a subsequent recognition task showing emotionally neutral faces. Half of the faces presented in the recognition task were initially shown in the encoding task. Results: Age interacted with the memory process: the ability to recognize both facial identity and emotional expression declined with advanced age. Happy facial expressions were better recognized in all age groups. Although there was a continuous overall decrease in recognition of both happy and angry expressions with advanced age, the effect favoring happy facial expressions was stable also in very old adults. Other factors such as gender or educational level did not affect the memory process for facial expressions. Conclusions: Our findings suggest that age is a significant determinant of memory for facial identity and emotional expression, and that, similar to younger adults, the recognition process of the elderly favors happy emotional facial expressions.  相似文献   
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目的:探讨腮腺深叶癌切除面神经后,即刻功能性修复的临床效果。方法:对1984年1月至2005年10月间收治的11例腮腺癌患者,术中采用将肿瘤连同腮腺及面神经切除,同时行颈丛神经移植重建面神经的治疗方法。结果:术后面神经功能均完全恢复,所有患者术后6个月复诊,见患者静态时面部对称,动态时口角轻度偏斜,术后一年两侧面部完全对称,睁、闭眼及提口角功能基本恢复正常。结论:腮腺癌根治术中采用颈丛神经移植能有效地恢复面神经的功能,既达到肿瘤切除的彻底性,又符合功能外科的发展要求,是一种比较理想的手术方法。  相似文献   
18.
Facial muscle spasms, which are rare in adults, present a particularly difficult entity for the optometrist to recognise. The condition may not even manifest itself at an eye examination and the optometrist may have to rely on subjective symptoms to assist in the recognition of the condition. It is important to diagnose the condition correctly as specific and effective treatment is available.  相似文献   
19.
We report on 7 patients (6 M, 1 F) with Coffin-Lowry syndrome who have a sensorineural hearing deficit in addition to developmental delay and characteristic facial changes. One of the patients also had a history of premature exfoliation of primary teeth. These are previously unappreciated clinical signs that may aid in the early diagnosis of Coffin-Lowry syndrome. Early diagnosis and recognition of a hearing deficit in the patient can lead to the use of hearing aids to help the patient achieve his or her full potential. These “;new”; clinical manifestations expand the phenotype of Coffin-Lowry syndrome and constitute an additional indication of pleiotropy. © 1993 Wiley-Liss, Inc.  相似文献   
20.
Congenital “healed” cleft lip (CHCL) is an unusual anomaly including a paramedian “scar” of the upper lip, which appears as if a typical cleft lip has been corrected in utero. The CHCL is frequently associated with an ipsilateral notch in the vermilion, and “collapsed” nostril. Twenty-five CHCL cases are presented, eighteen of which were an isolated malformation found among the 3,950,715 births examined in two similar birth defect registries: ECEMC in Spain and ECLAMC in Latin America. Like open cleft lip, of which it seems to be a variant, CHCL is most frequently seen among males (14/18 isolated cases), it preferentially affects the left side (10/18 cases), and it segregated together with cleft lip in one family. The five CHCL cases with other congenital anomalies included: two cases with hydrocephalus, two VACTERL associations, and one atypical oblique facial cleft infant with single umbilical artery. CHCL may result from a defective fusion of the frontonasal and maxillary processes (before week 7 of embryonic life), or from a spontaneously repaired open cleft lip, later on. In either way, these cases heal with a visible scar, and the pre-occurrence of CHCL in two families suggests a familial predisposition to this phenomenon. © 1995 Wiley-Liss, Inc.  相似文献   
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