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991.
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
992.
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
993.
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
994.
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
995.
996.
997.
Most patients with cri-du-chat syndrome have a de novo deletion of the short arm of chromosome 5 (5p). In order to perform extensive phenotype-genotype correlation studies, a relatively easy method for the precise determination of the extent of a patient's deletion is essential. Towards this purpose, a set of minimally overlapping YAC clones that span 5p was identified. A BAC that maps at or near the 5p telomere was also used. A total of 110 patients with previously determined de novo terminal deletions by standard cytogenetic approaches were reanalyzed using the YAC clones and fluorescent in situ hybridization (FISH). Of the 110 samples, 4 patients were determined to have interstitial deletions, 1 patient had an unbalanced translocation, and no deletion could be detected in 2 patients. The FISH results in the 7 patients affect the clinical prognosis for some of these patients. These results demonstrate the need for supplementing standard cytogenetics with FISH analysis when an abnormal karyotype is detected. 相似文献
998.
C. W. Ang K. Krogfelt P. Herbrink J. Keijser W. van Pelt T. Dalby M. Kuijf B. C. Jacobs M. P. Bergman P. Schiellerup C. E. Visser 《Clinical microbiology and infection》2007,13(9):915-922
Weeks or months following Campylobacter infection, a small proportion of infected individuals develop Guillain-Barré syndrome (GBS) or reactive arthritis (ReA). Stool culture for Campylobacter is often negative in these patients, and serology is therefore the method of choice for diagnosing a recent infection with Campylobacter. This study developed a capture ELISA system to detect anti-Campylobacter IgA and IgM antibodies indicative of a recent infection. The sensitivity of the assay was 82.0% in uncomplicated Campylobacter enteritis patients, 96.2% in GBS patients who were culture-positive for Campylobacter, and 93.1% in culture-positive ReA patients, with a specificity of 93.0%. The assay allows identification of Campylobacter infection in patients with post-infectious neurological and rheumatological complications. 相似文献
999.
1000.
F. Encha-Razavi J. C. Larroche J. Roume G. Migne Al. Delezoide M. Gonzales N. Mulliez 《American journal of medical genetics. Part A》1992,42(1):44-50
We report on congenital hypothalamic hamartomas, discovered at autopsy in 3 unrelated fetuses. In the first 2 patients, the tumor was associated with skeletal dysplasia only. In the third patient, it was part of a non-random congenital malformation association, suggestive of Meckel syndrome. In one family, a previous boy died soon after birth with similar craniofacial and skeletal abnormalities. As far as we know, the association between isolated skeletal dysplasia and congenital hypothalamic hamartomas has not yet been documented in the literature. Nevertheless, a spectrum of skeletal abnormalities has been described in association with congenital hypothalamic “hamartoblastoma” and a constellation of variable visceral malformations under the eponym of “Pallister-Hall syndrome” (PHS). A detailed analysis of the PHS reported cases shows that only skeletal dysplasia and oro-facial abnormalities are present constantly. They show similarities with those found in our first 2 cases. These findings prompt us to consider skeletal dysplasia and oro-facial abnormalities as common denominator and minimum criteria required to define a nosologically distinct, possibly familial entity, which we suggest calling “congenital hypothalamic hamartoma syndrome” (CHHS). 相似文献