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101.
The inherited inability to synthesize cortisol is termed congenital adrenal hyperplasia. More than 90% of cases are caused by 21-hydroxylase deficiency. This syndrome is characterized by signs of androgen excess and often mineralocorticoid deficiency. Steroid 21-hydroxylase (P450c2l) is a microsomal enzyme expressed in the adrenal gland that catalyzes conversion of 17-hydroxyprogesterone and progesterone to 11-deoxycortisol and deoxycorticosterone respectively. In man, this enzyme is encoded by the CYP21 (CYP21B) gene which is located in the HLA major histocompatibility complex along with a pseudogene, CYP21P (CYP21A). Mutations in CYP21 causing congenital adrenal hyperplasia are almost all generated by recombinations between CYP21 and CYP21P. These recombinations either delete CYP21 or transfer deleterious mutations from CYP21P to CYP21, a process termed apparent gene conversion. The degree of enzymatic compromise caused by each mutation is correlated with the clinical severity of the deficiency observed in patients carrying that mutation. © 1994 Wiley-Liss, Inc.  相似文献   
102.
目的:探讨人工补片无张力疝修补术的疗效和优点。方法:对59例71个腹外疝在疝囊高位结扎后行人工补片无张力修补术的临床效果进行回顾性分析。结果:本组51例63个腹股沟疝和股疝的手术时间为30—80min,平均55min。术后切口均一期愈合,无切口感染、硬结、异物反应等并发症;术后并发短暂尿潴留2例;阴囊血肿2例、积液4例5侧。腹股沟疝术后5~7天(平均6天)出院,切口疝术后8-11天(平均9天)出院。随访5—51个月,复发2例。结论:人工补片无张力疝修补术是一种简单、安全、痛苦小、恢复快、效果好的疝修补方法,适用于腹壁缺损不严重的各种腹外侧及复发疝。  相似文献   
103.
Summary Two unrelated patients with severe arthrogryposis multiplex congenita (AMC) who died perinatally, are presented. In both, postmortem examination revealed an intact nervous system and striking dystrophic muscle changes, consistent with congenital muscular dystrophy (CMD). Few similar cases have been reported before, but since the condition is not well known, it seems probable that in the past many have been labeled as mere multiple malformations. The possibility of an underlying muscular disorder, either primary myopathic or neurogenic should be considered in any patient with early lethal AMC. Our findings confirm that the fetal akinesia-arthrogryposis sequence is a nonspecific clinical syndrome resulting from various causes of muscular inactivity in utero. The main objective of this report is to provide reasonable guidelines on how to approach the problem of classification. We favor a pathogenetic approach, depending upon careful sampling of the central nervous system and skeletal muscles at autopsy.  相似文献   
104.
105.
目的探讨脐带穿刺在胎儿先天性心脏病诊疗中的应用价值。方法对34例行脐带穿刺的胎儿先天性心脏病例进行回顾性分析。结果34例均穿刺成功,未发生严重并发症。检出染色体异常6例,宫内巨细胞病毒感染1例。结论脐带穿刺术是一种安全有效改善妊娠结局的产前诊疗技术。  相似文献   
106.
为了解先天性肾上腺皮质增生症患者的21-羟化酶CYP21B基因中Ile~(172)→Asn错义突变的发生率,根据放大受阻突变体系(Amplificationrefractorymutationsystem,ARMS)的要求,设计了3种引物:5'd(TTGGGAGACTACTCCCTGCTCT)3'(共同引物)、5'd(AGGTGAGGTAACAGA)3'(正常引物)、5'd(AGGTGAGGTAACAGT)3'(突变引物),在7例患儿中进行了检测,发现具有本突变者3例。对其中一例进行的家系分析,结果提示:这组引物有快速、简便的优点,不需使用同位素就能对具有Ile~(172)→Asn变异的高危家庭成员作产前诊断。  相似文献   
107.
大连地区35068例围产儿中先天性心脏病的调查   总被引:1,自引:1,他引:1  
目的为了解我院围产儿先天性心脏病发病情况.方法对2000年1月~2003年12月大连市妇幼保健院分娩的围产儿35068例进行前瞻性调查.结果查出先心病487例,其中彩色多普勒超声心动图诊断467例,尸检确诊20例.发病率13.9‰.以单纯性室间隔缺损(VSD)20.95%和房间隔缺损(ASD)18.07%居多,其中又以.膜部VSD和Ⅱ孔型ASD最多.复合型畸形占41.68%,以ASD VSD(12.73%)居多.出生~7d发生心力衰竭59例.围产儿死亡52例,死亡率1.48‰,占1岁以内先心病死亡总数的67.53%.以青紫型复杂畸形为主.结论先心病的发生与母亲早期呼吸道病毒感染有关(χ2=20.98,P<0.01,相对危险度5.99).PDA的发生与早产儿密切相关(χ2=29.1,P<0.01,相对危险度5.01).  相似文献   
108.
Genetic screening of Congenital Adrenal Hyperplasia (CAH) is known to be challenging due to the complexities in CYP21A2 genotyping and has not been the first-tier diagnostic tool in routine clinical practice. Also, with the advent of massive parallel sequencing technology, there is a need for investigating its utility in screening extended panel of genes implicated in CAH. In this study, we have established and utilized an Allele-Specific Polymerase Chain Reaction (ASPCR) based approach for screening eight common mutations in CYP21A2 gene followed by targeted Next Generation Sequencing (NGS) of CYP21A2, CYP11B1, CYP17A1, POR, and CYP19A1 genes in 72 clinically diagnosed CAH subjects from India. Through these investigations, 88.7% of the subjects with 21 hydroxylase deficiency were positive for eight CYP21A2 mutations with ASPCR. The targeted NGS assay was sensitive to pick up all the mutations identified by ASPCR. Utilizing NGS in subjects negative for ASPCR, five study subjects were homozygous positive for other CYP21A2 variants: one with a novel c.1274G>T, three with c.1451G>C and one with c.143A>G variant. One subject was compound heterozygous for c.955C>T and c.1042G>A variants identified using ASPCR and NGS. One subject suspected for a Simple Virilizing (SV) 21 hydroxylase deficiency was positive for a CYP19A1:c.1142A>T variant. CYP11B1 variants (c.1201-1G>A, c.1200+1del, c.412C>T, c.1024C>T, c.1012dup, c.623G>A) were identified in all six subjects suspected for 11 beta-hydroxylase deficiency. The overall mutation positivity was 97.2%. Our results suggest that ASPCR followed by targeted NGS is a cost-effective and comprehensive strategy for screening common CYP21A2 mutations and the CAH panel of genes in a clinical setting.  相似文献   
109.
Dermatoglyphic findings were compared in 42 patients (32 females, 10 males) with Congenital Adrenal Hyperplasia (CAH) and 110 normal controls (70 females, 40 males). In CAH males, an excess of whorls (p less than 0.001), an increased total finger ridge count (p less than 0.05), and an increased frequency of patterns in the fourth interdigital area (p less than 0.025) was found. A main line A terminating high in the hypothenar area (p less than 0.05), and a missing c-triradius or an abortive main line C (p less than 0.05) was observed in CAH females. Both sexes displayed an increase in the frequency of small radially directed hypothenar patterns (p less than 0.05) and sydney lines (p less than 0.01).  相似文献   
110.
Trisomy 6qter   总被引:2,自引:0,他引:2  
A previously reported patient with trisomy for the distal part of 6q was shown by R-banding to be trisomic for 6q26qter, due to a t(6;22)(q26;p12) mat. Altogether nine patients with 6qter trisomy have been reported. The main features of the 6qter trisomy syndrome are: severe mental and growth retardation; acrocephaly and brachycephaly; a carp-shaped mouth; micrognathia; a very short neck with unusual anterior webbing; joint contractures; the absence of severe inner organ malformations; and survival into adulthood.  相似文献   
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