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Proteus syndrome is a multi–organ disorder, a prime feature of which is localized gigantism, usually clinically obvious. Symptoms secondary to hypertrophy of nerves has not been previously recognized as a part of the syndrome. Accepted: 16 May 1997  相似文献   
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BACKGROUND: The informed consent procedure plays a central role in randomised controlled trials but has only been explored in a few studies on children. AIM: To assess the quality of the informed consent process in a paediatric setting. METHODS: A questionnaire was sent to parents who volunteered their child (230 children) for a randomised, double blind, placebo controlled trial of ibuprofen syrup to prevent recurrent febrile seizures. RESULTS: 181 (79%) parents responded. On average, 73% of parents were aware of the major study characteristics. A few had difficulty understanding the information provided. Major factors in parents granting approval were the contribution to clinical science (51%) and benefit to the child (32%). Sociodemographic status did not influence initial participation but west European origin of the father was associated with willingness to participate in future trials. 89% of participants felt positive about the informed consent procedure; however, 25% stated that they felt obliged to participate. Although their reasons for granting approval and their evaluation of the informed consent procedure did not differ, relatively more were hesitant about participating in future. Parents appreciated the investigator being on call 24 hours a day (38%) and the extra medical care and information provided (37%) as advantages of participation. Disadvantages were mainly the time consuming aspects and the work involved (23%). CONCLUSIONS: Parents' understanding of trial characteristics might be improved by designing less difficult informed consent forms and by the investigator giving extra attention and information to non-west European parents. Adequate measures should be taken to avoid parents feeling obliged to participate, rather than giving true informed consent.  相似文献   
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CONTEXT: Although protease inhibitors are used routinely in adults with human immunodeficiency virus (HIV) infection, the role of these drugs in the treatment of clinically stable HIV-infected children is not clear. OBJECTIVE: To evaluate the safety, tolerance, and virologic response produced by a change in antiretroviral therapy in HIV-infected children who were clinically and immunologically stable while receiving previous therapy. DESIGN: The Pediatric AIDS Clinical Trials Group 338, a multicenter, phase 2, randomized, open-label controlled trial conducted from February 6 to April 30, 1997 (patient entry period); patients were followed up for 48 weeks. SETTING: Pediatric HIV research clinics in the United States and Puerto Rico. PATIENTS: Two hundred ninety-seven antiretroviral-experienced, protease inhibitor-naive, clinically stable HIV-infected children aged 2 to 17 years. INTERVENTIONS: Children were randomized to receive zidovudine, 160 mg/m2 3 times per day, plus lamivudine, 4 mg/kg 2 times per day (n = 100); the same regimen plus ritonavir, 350 mg/m2 2 times per day (n = 100); or ritonavir, 350 mg/m2 2 times per day, and stavudine, 4 mg/kg 2 times per day (n = 97). MAIN OUTCOME MEASURE: Plasma HIV-1 RNA levels at study weeks 12 and 48, compared among the 3 treatment groups. RESULTS: At study week 12, 12% of patients in the zidovudine-lamivudine group had undetectable plasma HIV RNA levels (<400 copies/mL) compared with 52% and 54% of patients in the 2- and 3-drug ritonavir-containing groups, respectively (P<.001). Through study week 48, 70% of children continued receiving their ritonavir-containing regimen. At study week 48, 42% of children receiving ritonavir plus 2 nucleosides compared with 27% of those receiving ritonavir and a single nucleoside had undetectable HIV RNA levels (P = .04); however, similar proportions in each group continuing initial therapy had HIV RNA levels of less than 10000 copies/mL (58% vs 48%, respectively; P = .19). CONCLUSIONS: In our study, change in antiretroviral therapy to a ritonavir-containing regimen was associated with superior virologic response at study week 12 compared with change to a dual nucleoside analog regimen. More children receiving ritonavir in combination with 2 compared with 1 nucleoside analog had undetectable HIV RNA levels at study week 48.  相似文献   
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植入前诊断是产前诊断非常早的一种方法,目的是放弃携带严重遗传病的胚胎,将健康胚胎植入母体。两种主要的方法是聚合酶链反应(PCR)和荧光原位杂交(FISH)。PCR用于单基因病诊断,FISH用于染色体异常诊断。临床主要应用于存在遗传风险的患者如携带单基因病和染色体易位的患者。随着分子生物学技术的飞速发展,如比较基因组(CGH),全基因组扩增技术(WGA),引物延伸预扩增(PEP),间期核转换技术及DNA芯片技术(DNAchip)等PGD先进检测手段的应用,单细胞用于诊断单基因或多基因突变及染色体疾病,为期不远。  相似文献   
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目的:检测急性白血病(acute leukemia,AL)病人谷胱甘肽硫转移酶-π(glutathione—S—transferltse-π,GST-π)、多药耐药相关蛋白1(multi—drug resistance relevant protein 1,MRP1)的表达,探讨二者与AL多药耐药(multi—drug resistance,MDR)的关系及临床意义,明确二者在AL中的表达有无相关性以及两者表达与AL病人临床特征的关系。方法:采用免疫组织化学S—P法检测80例AL病人及30例正常人外周血单个核细胞GST-π、MPP1表达。运用SPSS10.0统计软件,采用X^2检验、四格表精确概率法、t检验、直线相关分析方法统计结果。结果:GST-π、MRP1在难治组的阳性率均高于初治组和完全缓解组;在初治组的阳性率均高于对照组。GST-π、MRP1在AL难治组中的表达具有高度相关性。GST-π、MRP1表达阳性组完全缓解率低于阴性组。GST-π、MRP1的表达与AL难治组病人年龄、性别、骨髓幼稚细胞比例及外周血白细胞计数无关。且两者在急性淋巴细胞白血病(acute lymphoblastic leukemia,ALL)组、急性非淋巴细胞白血病(acute nonlymphoblastic leukemia,ANLL)组表达无差别。结论:GST-π和MRP1的高表达与AL临床耐药有关;GST-π和MRP1在难治组中的表达密切相关;GST-π和MRP1表达阳性的AL病人的完全缓解率明显降低,两者可能是影响AL疗效的重要指标;GST-π和MRP1在难治组表达阳性率与年龄、性别、外周血白细胞计数、骨髓幼稚细胞比例可能无关,且在ALL组与ANLL组中差别无统计学意义。  相似文献   
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目的:了解基质金属蛋白酶-2(MMP-2)及转化生长因子-β1(TGF-β1)在心肌梗死大鼠左室重构及心衰发展过程中的改变,以及氟伐他汀的干预作用,探讨心梗后心衰的发生机制。方法:选用雄性SD大鼠67只随机分为假手术组、心梗组和心梗他汀组,经冠状动脉前降支结扎术建立心肌梗死后心衰模型,手术24 h后心梗他汀组大鼠管饲氟伐他汀4 mg·kg-1·d-1,假手术组和心梗组大鼠管饲安慰剂。术后3 d、4周、8周检测大鼠非梗死区心肌MMP-2的含量(Western-blot法)、胶原、TGF-β1的改变(免疫组化法),压力传感器记录左室血流动力学改变。结果:术后各时点非梗死区心肌的MMP-2含量,心梗组及心梗他汀组显著高于假手术组(P<0.05),而心梗他汀组显著低于心梗组(P<0.05);术后各组各时点非梗死区心肌TGF-β1表达的变化趋势与MMP-2相同;与心梗组比较,心梗他汀组术后4周和8周的心功能明显改善,胶原容积分数(CVF)及Ⅰ/Ⅲ型胶原比值(Ratio of type Ⅰ/Ⅲ)降低(P<0.05)。结论:氟伐他汀通过减少非梗死区心肌MMP-2和TGF-β1的含量,而减轻心梗后非梗死区心肌胶原网络的破坏及反应性胶原的过度沉积,从而预防和逆转心室重构,改善心脏功能。  相似文献   
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