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991.
Summary We report on a sporadic case satisfied with a proposed diagnostic criteria for Cohen syndrome. This 10 year-old Japanese boy
had truncal obesity, short stature, mild mental retardation, hypotonia, maxillary hypoplasia, micrognathia, narrow hands and
feet, high-arched palate, prominent upper central incisors, high nasal bridge, but no pigmentary retinopathy. Autosomal recessive
manner of inheritance was suggested by the pedigree. 相似文献
992.
Karl-Henrik Gustavson Ylva Flodérus Sten Jagell Lennart Wetterberg Svante B. Ross 《Clinical genetics》1982,22(1):22-24
Catechol-O-methyltransferase (COMT) activity in erythrocytes was measured in six children with Down's syndrome and in their parents to determine if COMT activity is related to a gene on chromosome 21. A gene dosage effect was a possible explanation of the COMT value in three of the children but not in the other three. 相似文献
993.
L.E. Scutt E.W.C. Chow R. Weksberg W.G. Honer Anne S. Bassett 《American journal of medical genetics. Part A》2001,105(8):713-723
Congenital dysmorphic features are prevalent in schizophrenia and may reflect underlying neurodevelopmental abnormalities. A cluster analysis approach delineating patterns of dysmorphic features has been used in genetics to classify individuals into more etiologically homogeneous subgroups. In the present study, this approach was applied to schizophrenia, using a sample with a suspected genetic syndrome as a testable model. Subjects (n = 159) with schizophrenia or schizoaffective disorder were ascertained from chronic patient populations (random, n = 123) or referred with possible 22q11 deletion syndrome (referred, n = 36). All subjects were evaluated for presence or absence of 70 reliably assessed dysmorphic features, which were used in a three‐step cluster analysis. The analysis produced four major clusters with different patterns of dysmorphic features. Significant between–cluster differences were found for rates of 37 dysmorphic features (P < 0.05), median number of dysmorphic features (P = 0.0001), and validating features not used in the cluster analysis: mild mental retardation (P = 0.001) and congenital heart defects (P = 0.002). Two clusters (1 and 4) appeared to represent more developmental subgroups of schizophrenia with elevated rates of dysmorphic features and validating features. Cluster 1 (n = 27) comprised mostly referred subjects. Cluster 4 (n = 18) had a different pattern of dysmorphic features; one subject had a mosaic Turner syndrome variant. Two other clusters had lower rates and patterns of features consistent with those found in previous studies of schizophrenia. Delineating patterns of dysmorphic features may help identify subgroups that could represent neurodevelopmental forms of schizophrenia with more homogeneous origins. © 2001 Wiley‐Liss, Inc. 相似文献
994.
We describe a family with at least seven living persons who are affected by an hitherto undescribed autosomal-dominant syndrome with variable expression, bearing close resemblance to the EEC syndrome and related disorders. The main manifestations are hypodontia and/or early loss of permanent teeth, ectrodactyly, obstruction of lacrimal ducts, onychodysplasia, and excessive freckling. We propose the acronym ADULT (acro-der-mato-ungual-lacrimal-tooth)-syndrome for this condition. © 1993 Wiley-Liss, Inc. 相似文献
995.
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
996.
The recent demonstration that about 20–30% of cases of Down syndrome are of paternal origin has again raised interest in the question of the possible contribution of paternal age independent of maternal age to a couple's risk of a Down syndrome live birth. In this paper the nature of the available evidence is critically reviewed, interpretations reconciling differences between studies that reached opposite conclusions are presented, and an approach to genetic counseling in the face of such apparent differences in the literature is discussed. It is not likely that data from ad hoc studies of parental origin of the extra chromosome will be sufficient to judge the existence or magnitude of paternal age-specific risk, and reliance must be made on statistical studies that searched for paternal age effects while controlling for maternal age. The literature is consistent with an apparent doubling of risk for paternal age 55 and over, but no effect at younger paternal ages. With regard to remarriage, it is suggested that if members of a couple with a 47, +21 child remarry it be assumed that the excess risk “travels” to that new couple which includes the parent in whom non-disjunction occurred in the previous marriage. If parental origin is not known, it is suggested that the risk be calculated on the assumption of a 20–30% likelihood that it was of paternal origin and a 70–80% likelihood that it was of maternal origin, and that the excess empiric risks be apportioned accordingly in the new marriages. 相似文献
997.
Ray V. Haning Ian H. Carlson Enid F. Gilbert Sander S. Shapiro John M. Opitz Laurence E. Karp 《American journal of medical genetics. Part A》1980,7(3):279-292
The second case of virilism as a late manifestation of Bardet-Biedl syndrome (BBS) is described, with endocrine and histological evaluation. Both cases manifested ovulatory cycles and developed virilism in adulthood. Elevated plasma testosterone and 17-OH-progesterone were not suppressed by dexamethasone but were suppressed by medroxyprogesterone acetate. Peripheral and ovarian venous blood obtained at the time of surgery demonstrated a marked gradient for testosterone in both ovaries and for progesterone in the ovary bearing the corpus luteum. Histological evaluation of the ovaries demonstrated bilateral ovarian stromal hyperplasia with focal hyperthecosis. Bilateral ovariectomy resulted in complete correction of the endocrine abnormality, although the established hirsutism remains a mark of previous androgen excess. 相似文献
998.
Jeffrey A. Kuller Victoria A. Cox Steven A. Schonberg Mahin Golabi 《American journal of medical genetics. Part A》1992,43(3):647-650
We report 3 cases of Pallister-Hall syndrome involving hypothalamic hamartoblastoma, hypopituitarism, cranial, and limb abnormalities. The first 2 cases represent the first apparent sibs reported with this syndrome. Patient 1 represents the first known patient with this syndrome with an abnormal karyotype. 相似文献
999.
目的:观察挤压伤大鼠血浆心钠素(ANP)、内皮素-1(ET-1),血清心肌肌钙蛋白I(cTnI)浓度的改变,阐明心钠素、内皮素与心脏损伤的关系。方法:复制挤压伤大鼠动物模型,全自动生化分析仪检测血清心肌酶改变,放射免疫法检测血浆ANP,ET-1水平,化学发光法检测血清cTnI浓度。结果:挤压伤后12 h,血浆ET-1显著低于对照组,血浆ANP、血清心肌酶、cTnI水平显著高于对照组,并持续48 h以上。结论:肢体挤压伤早期存在心肌细胞的损伤,其损伤可能与ANP、ET-1有重要关系。 相似文献
1000.