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31.
Hirschsprung disease (HSCR) is a congenital disorder characterized by an absence of ganglion cells in the nerve plexuses of the lower digestive tract. Although mutations in eight different genes (EDNRB, EDN3, ECE1, SOX10, RET, GDNF, NTN, SIP1) have been identified in affected individuals, it is now clear that RET and EDNRB are the primary genes implicated in the etiology of HSCR. All eight genes are involved in the early development of the enteric nervous system, and most act through two distinct biochemical pathways mediated by RET and EDNRB. Mutations in RET and EDNRB account for up to 50% and 5% of HSCR cases in the general population, respectively. Interaction between these two signaling pathways could modify RET expression and, therefore, HSCR phenotype. Here, we report the case of a 1-year-old Taiwanese boy who presented with abdominal distension since birth and bilious vomiting after feeding. HSCR (short-segment type) was diagnosed based on X-ray, lower gastrointestinal series and biopsy findings. Mutation analysis revealed a heterozygous T>C missense mutation in exon 1 of the EDNRB gene, that substitutes the highly conserved cysteine-90 residue in the extracellular domain of the G protein-coupled receptor with an arginine residue (C90R). No RET gene mutation was detected in this patient.  相似文献   
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Legionella pneumophila is a common cause of sporadic community-acquired pneumonia, but culture-proven legionellosis is rarely diagnosed. There is no laboratory test for Legionnaires' disease that can detect all patients with the disease. Culture is the standard diagnostic method and should be initiated as soon as possible in suspected cases. We describe a rare case of community-acquired pneumonia caused by L. pneumophila serogroup 6. A 77-year-old man was admitted to a tertiary care hospital because of high fever, productive cough, and progressive dyspnea. Chest radiography showed bilateral pneumonia, which led to respiratory failure necessitating mechanical ventilatory support. Despite antibiotic therapy, his condition continued to deteriorate and acute renal failure also developed. Urine was negative for L. pneumophila. Culture of the sputum yielded L. pneumophila serogroup 6, although there was no elevation of the serum antibody titer. Pneumonia resolved gradually and he was extubated after treatment with levofloxacin followed by erythromycin. L. pneumophila other than serogroup 1 should be included in the differential diagnosis of patients with suspected atypical community-acquired pneumonia.  相似文献   
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Abstract: Background: Identification of risk drinking in expectant fathers may be helpful as an important part of efforts to minimize maternal alcohol use, and as an opportunity to inform them about a problematic practice during a critical developmental stage for the couple. The purpose of this study was to evaluate the T‐ACE screening questionnaire, which asks about t olerance to alcohol, being a nnoyed by other's comments about drinking, attempts to c ut down, and having a drink first thing in the morning (“ e ye‐opener”), in the male partners of pregnant women who themselves were T‐ACE positive. Methods: Two hundred fifty‐four male partners were asked to complete the T‐ACE embedded in a health survey, the Alcohol Use Disorders Identification Test (AUDIT), and other questions about their alcohol use in the past 30 days when their pregnant partners had a median gestation of 11.5 weeks (T1). After delivery, male partners again completed the T‐ACE and quantity‐frequency questions (T2). The predictive ability of the T‐ACE and AUDIT was compared, using risk drinking (>4 drinks/day or >14 drinks/week) as the criterion standard. Results: A substantial minority of male partners had risk drinking, 31 percent at T1 and 25 percent at T2. Although the AUDIT was better than the T‐ACE as an independent predictor of risk drinking, the latter was most accurate when the tolerance threshold exceeded 2 drinks, the same established for pregnant women. The sensitivity (T1 = 84.6%, T2 = 82.8%) and specificity (T1 = 43.8%, T2 = 51.1%) of the T‐ACE at this threshold compared favorably with those of the AUDIT at the standard cut point of 8. Conclusions: The T‐ACE may be a practical way for clinicians to identify risk drinking in both pregnant women and expectant fathers. (BIRTH 33:2 June 2006)  相似文献   
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目的 探讨甲状腺99TcmO-4 显像冷结节对不同性质甲状腺疾病的诊断价值。方法 采用静脉注射99TcmO-4 185MBq ,2 0min后甲状腺前位静态显像 ,采集总计数 1× 10 6。显像显示甲状腺结节局部放射性分布缺损或低于正常甲状腺组织则定性为冷结节。结果  34 2例甲状腺99TcmO-4 显像发现冷结节 85例 ,发生率为2 4.9% ,85例冷结节中 ,37例 (4 3.5 % )为甲状腺瘤 ,15例为甲状腺癌 (17.6 % ) ,2 0例 (2 3.5 % )为结节性甲状腺肿 ,8例 (9.4% )为甲状腺炎 ,4例 (4 .7% )为单纯性甲状腺囊肿 ,1例 (1.3% )为甲状腺外肿物。结论 冷结节在甲状腺99Tcm O-4 显像时较为常见 ,且不同性质甲状腺疾病的冷结节及其周围组织有一定的特征性表现 ,因此99TcmO-4显像冷结节对甲状腺腺瘤、甲状腺癌、甲状腺囊肿、甲状腺炎等常见疾病具有较高的临床价值。  相似文献   
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晶体玻璃体视网膜联合手术治疗复杂性视网膜脱离   总被引:6,自引:2,他引:4  
目的探讨玻璃体视网膜手术(vitreretinalsurgery,VR术)联合晶体切除/超声粉碎的效果。方法对81例(81只眼)应用晶体玻璃体视网膜联合手术(lenticular-vitreoretinalsurgery,LVR术)治疗的复杂性视网膜脱离进行回顾性分析。结果解剖性成功者64只眼(79.01%),功能性成功者45只眼(55.56%);手术成功率显著降低的原因是前部增殖性玻璃体视网膜病变(proliferativevitreo-retinopathy,PVR)(成功率42.86%,P<0.01)和术中/术后眼内出血(成功率58.82%,P<0.025)。结论LVR术是治疗复杂性视网膜脱离的主要方法;显著影响手术预后的因素是前部PVR和术中/术后眼内出血。  相似文献   
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混合Poisson分布及其应用:疾病的统计分布(五)   总被引:4,自引:0,他引:4  
本文讨论了混合Poisson分布的性质、应用条件、参数的估计及混合Poisson分布阶数的确定,指出混合Poisson分布可用于混合样本的判别归类,并用Bayes的思想导出其判别归类方法。模拟试验结果表明:当混合Poisson分布中各部分的比例相差不大,而各部分的均值相差较大时,抽样效果和拟合效果越好,所得到的估计值越接近理论值;反之效果越差。  相似文献   
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