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41.
During the development of motor vagal nuclei (MVN), the neuroblasts of the myeloencephalic basal plate migrate in the dorsolateral direction to form the dorsal motor vagal nucleus (DMVN) and ventrolaterally to form the ventral motor vagal nucleus (VMVN). Those neuroblasts that remain close to the median sulcus will form the hypoglossal nucleus. In support of the congenital origin of the alteration of the MVN in sudden infant death syndrome (SIDS), we report the case of an 8‐month‐old female child who was found dead in her cot. The neuropathological assessment revealed that the medullary triangle of the 4th ventricle floor was asymmetric, owing to the presence of three prominences to the left side of the median sulcus. The medial prominence corresponded to the hypoglossal nucleus, which showed a marked increase in the number of large neurons; the intermediate prominence corresponded to the DMVN whose large neurons were reduced and were recognizable mainly at the level of the medial fringe; the lateral prominence corresponded to the solitary nucleus. The left solitary tract showed a reduction of the transverse diameter. Also, the left VMVN showed marked reduction in the number of neurons. Inflammatory and astrocytic reactions were absent. We suggest that in SIDS cases the hypocellularity of the MVN and the increased number of neurons of the hypoglossal nucleus are intimately related, indicating a congenital alteration due to incomplete migration of the vagal neuroblasts with abnormality of the autonomic cardio‐respiratory control.  相似文献   
42.
We report on a Thai family with dominantly inherited malformation syndrome with upper limb anomalies, short stature, quadricuspid aortic valve, and minor craniofacial anomalies. The affected individuals comprised a mildly affected mother, a moderately affected daughter, and a most severely affected son. The daughter and son had short stature. The craniofacial abnormalities comprised frontal bossing, hypoplastic nasal bones, depressed nasal bridge, and broad nasal alae. The upper limb defects varies among the patients, ranging from radial ray defects in the mother through radial and ulnar ray defects with unilateral humeral hypoplasia in the daughter to radial ray defects with severe oligodactyly and bilateral humeral hypoplasia in the son. All patients in this family had hypoplasia of the shoulder girdle and resembled what is observed in many families with Holt‐Oram syndrome. Moreover, the son showed quadricuspid aortic valve with mild aortic regurgitation. However, the present family did not show any mutation of the TBX5 gene, a disease‐causing gene of Holt‐Oram syndrome. The present family deserves further investigation on other genes that play a role in the development of the upper limbs, particularly of radial rays. © 2002 Wiley‐Liss, Inc.  相似文献   
43.
Summary A patient who developed a unilateral opercular syndrome following a cerebrovascular accident is described. Computed tomography showed that the lesion did not affect the opercular cortex, but involved deep white matter and the head of the caudate nucleus of the left hemisphere. Persistent hypophonia and transient aphasia were associated. Comparison with previous cases is discussed.  相似文献   
44.
X chromosome instability associated with familial Turner syndrome   总被引:1,自引:0,他引:1  
A family with two members (two generations) exhibiting Turner syndrome is described. Cytogenetic studies on these individuals showed the presence of multiple X chromosome changes. Evidence is presented to show that the maternally inherited X chromosome is the chromosome involved in the structural alterations observed. The effect of a tendency of the maternal X chromosome to break at specific sites on the development of the Turner phenotype and abnormal karyology is discussed.  相似文献   
45.
Anorectal function in the solitary rectal ulcer syndrome   总被引:8,自引:6,他引:2  
The anorectal function of nine patients with solitary rectal ulcer syndrome (SRUS) (5 F: 4 M, median age, 27 (range, 19–41 years) and nine control subjects (5 F: 4 M, median age, 47 (35–66)P<0.01) has been investigated by a new technique that radiologically visualizes the anorectum during voiding of a semisolid contrast medium, while simultaneously measuring intrarectal pressure and anal sphincter EMG activity. A degree of rectal prolapse was demonstrated in eight of the SRUS patients; six of these lesions were clinically occult. Abnormal failure of the anal sphincter to relax on voiding was present in seven of the SRUS patients. These abnormalities resulted in the SRUS patients requiring a greater increase in intrarectal pressure (median, 100 cm water) to void than the control subjects (median, 65 cm water,P<0.01). This combination of high intrarectal pressure and rectal prolapse during straining seems to be the cause of SRUS This work was supported by a grant from the Medical Research Council.  相似文献   
46.
Advanced malignant melanomas of the uvea unsuited for an eye salvaging approach require enucleation of the tumor containing eye. A series of 68 patients is reported who underwent enucleation combined with insertion of a spherical dura-encased implant after 30 Gray pre-irridiation therapy of the orbit. Postoperative results with special attention to cosmetic outcome and motility of the prosthesis suggest that the insertion of an orbital implant should be preferred to the enucleation with no implant.  相似文献   
47.
A consecutive series of patients (1978–1981) comprising all patients with acute leukaemia from a population of 475000 inhabitants was reviewed. Thus, 94 patients were diagnosed as having acute leukaemia. No patients were lost from follow-up. The incidence figures of ALL and AML differed significantly from those of Sweden as a whole. 9 patients were < 15 years old. The median age of adult patients was 64 years, 60.8% being ≥ 60 years old. Of adult patients with AML, 20% had a preleukaemic history (chronic myeloproliferative disorders, myelodysplastic syndromes and others). None of 6 patients with leukaemia as a metamorphosis of a chronic myeloproliferative disorder achieved a complete remission. The overall remission rate of the remaining adult patients was 25%. Treated patients, 15–39 years old, with AML without any preleukaemic history, had a complete remission rate of 80% compared to 12% for patients ≥ 60 years old with the same diagnosis. Of 60 patients with ‘primary’ AML, 14 were not treated, mainly because of advanced age and complicating diseases. Most of these patients died within a week of admission.  相似文献   
48.
Amyloid P (AP) component is present in all types of systemic amyloid deposits. Recently, it has been shown to be also present in cerebral amyloid lesions of Alzheimer's disease (AD). In this study, we used immunocytochemical methods to extend these findings at the electron microscope level and characterize the spectrum of AP immunoreactivity in neurofibrillary pathology (NFP) of AD and other neurodegenerative disorders including Down's syndrome (DS), Creutzfeldt-Jakob, Parkinson's, Pick's and diffuse Lewy body diseases and progressive supranuclear palsy. In AD and DS, AP immunoreaction product was evident in all the classical amyloid lesions and NFP in a large sample of all cortical areas examined. The distribution and relative intensity of immunostaining was similar to that of thioflavin S staining in serial sections. In many cases, however, plaques and vessels stained by anti-AP serum were not apparent with thioflavin S. Serial sections immunostained with antiserum to amyloid A, C-reactive protein or to other proteins involved in systemic amyloidoses and the acute phase response showed no evidence of staining in any of the cerebral lesions. Electron microscopy confirmed that AP immunoreactivity was associated with the abnormal filaments characteristic of NFP as well as amyloid fibrils found in plaques and vessels showing congophilic amyloid angiopathy. Plaques of Creutzfeldt-Jakob disease, Pick bodies of Pick's disease, tangles and Lewy bodies in Parkinson's disease and a subpopulation of Lewy bodies in the diffuse Lewy body disease coexistent with AD were also stained. With the exception of vessels in two of the five cases, AP was not detected in age-matched controls. Our observations indicate AP to be a consistent feature of cerebral NFP and amyloid deposits.  相似文献   
49.
二甲基亚砜诱导人肝癌细胞BEL-7402凋亡的研究   总被引:2,自引:0,他引:2  
目的 :研究二甲基亚砜 (DMSO)对人肝癌细胞凋亡的诱导作用。方法 :用不同浓度的DMSO处理体外培养的人肝癌细胞BEL 74 0 2 ,应用普通光镜、荧光显微镜、MTT分析方法和流式细胞技术 (FCM )检测肝癌细胞凋亡的形态学变化、细胞存活率、凋亡百分率和细胞周期分布的变化。结果 :DMSO诱导BEL 74 0 2细胞核DNA凝缩和核片段化 ,最后形成凋亡小体 ;随着DMSO浓度的增加和处理时间的延长 ,细胞存活率明显下降 ,其IC50 为 1.9% ;2 %的DMSO处理细胞 12h ,凋亡率达 17.2 1% ,同时S期细胞明显增加 ,G2 M期细胞明显下降。结论 :DMSO可诱导人肝癌细胞凋亡 ,并使细胞受阻于S期而进入凋亡程序。  相似文献   
50.
本文对95例肾病综合征进行分析,探讨了性别、年龄、发病迁延时间、浮肿、蛋白尿、血尿、血压、尿素氮、血浆蛋白、血浆胆固醇、免疫球蛋白、补体C_3与激素反应及分型的关系。认为下列综合分析可做为判定难治性肾病综合征的参考。难治性肾病多分布在7岁以上,激素治疗4~8周血浆蛋白尚未恢复,尿镜检反复出现红细胞及颗粒管型,血清r—球蛋白不低,而补体C_3降低,提示难治性肾病。各种感染常常是造成肾病综合心难以控制,甚至死亡的重要因素。  相似文献   
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