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41.
Test of genetic heterogeneity of cleft lip with or without cleft palate as related to race and severity 总被引:6,自引:0,他引:6
The question of possible heterogeneity among population groups and phenotypic groups on the role of major gene in the etiology of cleft lip with or without cleft palate [CL(P)] was examined using the uniformly collected data in Hawaii. Complex segregation analysis was used to analyze patterns of family resemblance under the mixed model incorporating the effects of major gene and multifactorial inheritance. Analysis of the entire data showed superior fit of the mixed model including the effects of both major gene and multifactorial inheritance over the model of major gene alone or multifactorial inheritance alone. No significant heterogeneity could be detected between the high-incidence group (Oriental or Japanese) and the low-incidence group (non-Oriental) in the underlying general model, although higher heritability was observed in general. When families were classified into "severe" and "mild" phenotypes based on cleft lip vs. cleft lip and palate or unilateral vs. bilateral cleft in the proband, no significant differences could be detected between the two types in the underlying genetic model. 相似文献
42.
Pigments of the Gastrointestinal Tract: A Comparison of Light Microscopic and Electron Microscopic Findings 总被引:6,自引:0,他引:6
It is now apparent that light microscopy and histochemistry failed to identify correctly the nature and composition of pigments in various gastrointestinal tract melanoses. In most instances it was thought that the pigment was melanin or a melanin-like substance. Electron microscopy (EM) and electron-probe energy dispersive x-ray analysis have rectified these errors and have shown the following: in melanosis coli the pigment granules contain lipofuscin; in melanoses ilei the pigment granules may contain either silicates and titanium or hemosiderin; and in melanosis duodeni the pigment granules contain iron sulfide. In melanosis esophagi it is not clear what the pigment is; it could be melanin or lipofuscin. 相似文献
43.
内耳门周结构对内镜下脑桥小脑三角区手术的影响 总被引:3,自引:3,他引:3
目的:研究内耳门周结构对颞骨径路内镜下处理脑桥小脑三角区病变手术的影响,为临床开展相应手术提供参考。方法:在20例40侧成人尸头上模拟颞骨径路内窥镜手术,观察小脑下前动脉及内耳门后唇的变异,了解其对内窥镜导入及其手术的影响。结果:内耳门后唇隆起超过面神经脑桥小脑角段1/3以上者占27.5%(11侧)。小脑下前动脉在Ⅶ、Ⅷ脑神经外侧成袢者占22.5%(9侧)。内耳门后唇隆起合并小脑下前动脉袢在Ⅶ、Ⅷ脑神经之外侧者占7.5%(3侧)。结论:当内耳门后唇隆起超过面神经脑桥小脑角段1/3或小脑下前动脉弓在Ⅶ、Ⅷ脑神经之前时将对内窥镜导入有阻碍,当两种情况合并存在时要将内窥镜导入脑桥小脑三角区相当困难,不宜采用此种手术方式。 相似文献
44.
Roger L. Ladda Jonathan Zonana Jeanette C. Ramer Maria J. Mascari Peter K. Rogan 《American journal of medical genetics. Part A》1993,47(4):550-555
Brother were affected with severe congenital contractures, multiple cutaneous manifestations of ectodermal dysplasia, cleft lip/palate, and psychomotor and growth impairment. High resolution prometaphase chromosomes were normal. Molecular studies of DNA markers, closely flanking the X-linked hypohidrotic ectodermal dysplasia locus, did not show evidence of a submicroscopic deletion from the Xq12-q13 region. The parents and a normal sister exhibited none of these findings. This constellation of anomalies appears to represent a unique AR or XLR syndrome. © 1993 Wiley-Liss, Inc. 相似文献
45.
Robert E. Nickel De-Ann M. Pillers Mark Merkens R. Ellen Magenis Deborah A. Driscoll Beverly S. Emanuel Jonathan Zonana 《American journal of medical genetics. Part A》1994,52(4):445-449
Approximately 5% of children with neural tube defects (NTDs) have a congenital heart defect and/or cleft lip and palate. The cause of isolated meningomyelocele, congenital heart defects, or cleft lip and palate has been largely thought to be multifactorial. However, chromosomal, teratogenic, and single gene causes of combinations of NTDs with congenital heart defects and/or cleft lip and palate have been reported. We report on 3 patients with meningomyelocele, congenital heart defects, and 22q11 deletions. Two of the children had the clinical diagnosis of velo-cardio-facial syndrome (VCFS); both also have bifid uvula. The third child had DiGeorge sequence (DGS). The association of NTDs with 22q11 deletions has not been reported previously. An accurate diagnosis of the 22q11 deletions is critical as this micro-deletion and its associated clinical problems is transmitted as an autosomal dominant trait due to the inheritance of the deletion-bearing chromosome. We recommend that all children with NTDs and congenital heart defects, with or without cleft palate, have cytogenetic and molecular studies performed to detect 22q11 deletions. © 1994 Wiley-Liss, Inc. 相似文献
46.
Mitchell LE, Risch N. Correlates of genetic risk for non-syndromic cleft lip with or without cleft palate. Clin Genet 1993: 43: 255–260. © Munksgaard, 1993 Multivariate analysis was used to determine which characteristics: sex of the proband, sibling sex, severity of the proband's defect or family history, are the best predictors of recurrence risk among siblings of individuals with non-syndromic cleft lip with or without cleft palate (CL \pm P). Sibling recurrence risks are not significantly related to the sex of the proband. Severity of the proband's defect, classified by the extent of the lip defect (unilateral versus bilateral), was found to be a significant predictor of sibling recurrence, whereas involvement of the palate in the proband's defect was not. A positive family history of clefting (i.e. at least one affected first-degree relative in addition to the proband) and the sex of the sibling were also found to be significant predictors of sibling recurrence. The associations between sibling risk and family history, and sibling risk and bilaterality of the proband's defect appear to be mildly confounded. After adjusting for the effects of family history, the risk to siblings of probands with bilateral lip defects is twice the risk to siblings of probands with unilateral defects (O.R. = 2.00; 95% C.I. 1.25-3.19). A positive family history of clefting increases the risk to siblings by greater than 4-fold (O.R. =4.49; 95% C.I. 2.74-7.35), after adjusting for the extent of the proband's lip defect. These results provide a rational strategy for identifying subsets of the ‘at risk’ population which have markedly different recurrence risks. This information is important for genetic counseling, since it allows for more precise estimation of sibling recurrence risks in individual cases. Furthermore, our findings indicate that the power to detect linkage between a genetic marker or a candidate gene and CL \pm P will increase if the study population is ascertained through individuals with bilcteral clefts of the lip, rather than through individuals with either unilateral or bilateral CL \pm P. 相似文献
47.
A new inbred mouse strain, SW/Fr, developed from a random-bred SW stock has a 6% incidence of spontaneous cleft palate without cleft lip. SW/Fr mice close their palates comparatively late in development. After cortisone treatment, the mean of the distribution (mean time to reach palate stage 5) is shifted towards later gestational ages. There is no change in the variance of the distribution. These data lend further support to the hypothesis that cleft palate in mice may fit a model where a continuous distribution is separated into discontinuous parts by a developmental threshold, and that time of palate closure is an important component of liability to cleft palate. 相似文献
48.
Maeda S Suzuki S Moriya T Suzuki T Chida M Suda H Sakuma H Kondo T Sasano H 《Pathology international》2001,51(8):649-653
We report a case of isolated unilateral absence of a pulmonary artery. The first clinical symptom that was manifested in the patient was recurrent hemoptysis, and subsequent angiography revealed that the main pulmonary artery was absent in the right lung, which was being fed only from the systemic circulation. Right pneumonectomy was performed, and neither the main pulmonary artery nor its remnant was detected in the resected right lung. Histologically, there were many muscular vessels in the resected lung, with intimal proliferation, or with plexiform-like lesions. The alveolar septum was moderately thickened and alveolar capillary vessels were dilated. We examined the alveolar capillary endothelial cells of the resected lung for immunoreactivity to thrombomodulin (TM) and von Willebrand factor (vWF). The endothelial cells were negative for TM and positive for vWF, while in the normal lung control group, these cells were positive for TM and negative for vWF. We considered that the hemodynamics of the systemic circulation in the resected lung caused the alteration of immunohistochemical characteristics in alveolar capillary endothelial cells. 相似文献
49.
Chekhonin VP Lebedev SV Ryabukhin IA Petrov SV Gurina OI Dmitrieva TB Volkov AI Kashparov IA Skoblov YS 《Bulletin of experimental biology and medicine》2004,138(4):343-347
Preparations of I125-labeled monoclonal antibodies against neurospecific enolase and mouse plasma IgG1 were injected intravenously to rats immediately after unilateral occlusion of the middle cerebral artery. Radioactivity of I125-labeled monoclonal antibodies against neurospecific enolase in the brain tissue progressively increased, reached a maximum by the 48th hour, and remained practically unchanged after 72 h. At the same time radioactivity of labeled IgG1 in the brain tissue and radioactivity of both preparations in the blood, liver, spleen, kidneys, heart, and lungs decreased over 72 h. Selective accumulation of I125-labeled monoclonal antibodies against neurospecific enolase was less significant in the brain tissue of the contralateral hemisphere and cerebellum not exposed to ischemia.Translated from Byulleten Eksperimentalnoi Biologii i Meditsiny, Vol. 138, No. 10, pp. 388–392, October, 2004 相似文献
50.
Dvorak Abeliovich Esther Maor Nava Bashan Rivka Carmi 《American journal of medical genetics. Part A》1989,32(3):346-349
We report on three patients with duplication of distal 22q. One patient is a de novo carrier of the translocation t(21;22) (p13;q11), the other two are offspring of a translocation carrier t(10;22) (q26;q12). The clinical manifestations of these patients demonstrate the variability of the dup(22q) syndrome. 相似文献