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1.
作者分别用差速离心法及蔗糖梯度离心法制备胎盘微绒毛膜(PMM),用受体放射分析法研究了PMM的转铁蛋白受体(TfB),结果表明:两种方法制备的PMM均可用于受体分析,但差速离心法更为简便。测定60例产妇PMM的TfR,其数目为3.53±1.98×10~(12)个位点/mg膜蛋白,最大结合容量为6.33±4.21×10~(-12)mol/mg膜蛋白,Kd值为4.95±3.39×10~(-9)mol/L。受体结合反应体系最适实验条件为,膜蛋白浓度每管50μg,标记物浓度每管50 000cpm,孵育30分钟,B/F分离的聚乙二醇浓度为12%(W/V)。对TfR的特性研究表明:TfR与转铁蛋白的结合具有高度亲和力、高度特异性及可饱和性。 相似文献
2.
目的 :研究肺表面活性物质 (PS)治疗新生儿呼吸窘迫综合征 (NRDS)前后血管内皮分泌功能变化及可能的治疗机理。方法 :用PS制剂固尔苏治疗 18例NRDS患儿 ,于治疗前 3 0min ,治疗后 1、 6、 12、 2 4h ,用硝酸还原酶法测定NO (一氧化氮 )、放射免疫法测定ET (内皮素 )、 6 K PGF1α (6 酮前列环素 )。结果 :固尔苏治疗后患儿NO、 6 K PGF1α明显升高 ,ET明显下降 ,与治疗前比较有显著性差异 (P <0 0 1)。治疗后 1、 6、 12、 2 4hNO、6 k PGF1α、ET各组间两两比较无明显差异 (P >0 0 5 )。结论 :PS治疗NRDS的机理可能是通过改善血管内皮功能发挥作用 ,为用外源性NO吸入和静注前列环素辅助治疗NRDS提供可能的实验依据。 相似文献
3.
Terry Kwong MB BS FRACP Senior Fellow Elsa Valderrama MD Assistant Professor of Pediatric Pathology Carole Paley MD Assistant Professor of Pediatrics Norman Ilowite MD Associate Professor of Pediatrics 《Seminars in arthritis and rheumatism》1994,23(6)
Childhood sarcoidosis is a rare disorder with protean manifestations. The case of a child with prolonged fever, hepatosplenomegaly, pancytopenia, and systemic necrotizing vasculitis manifesting as fever, rash and skin infarctions, digital pregangrene, and foot drop is reported. This is the first case of systemic necrotizing vasculitis reported in sarcoidosis. The fulminant course of the disease required treatment with intravenous pulsed cyclophosphamide and high doses of corticosteroids. The spectrum of vasculitis in childhood and adult sarcoidosis is reviewed. 相似文献
4.
采用中药与行为干预综合治疗的方法对140名轻、中度精神发育迟滞的儿童进行分组康复观察。结果发现中药加行为干预组治疗后智力商数(IQ)及能力的变化最大,明显优于单用中药组和单纯行为干预组(P<0.01);与对照组相比有非常显著的差异(P<0.001)。从而为精神发育迟滞儿童的康复治疗提供了新的途径。 相似文献
5.
Massa O Iafusco D D'Amato E Gloyn AL Hattersley AT Pasquino B Tonini G Dammacco F Zanette G Meschi F Porzio O Bottazzo G Crinó A Lorini R Cerutti F Vanelli M Barbetti F;Early Onset Diabetes Study Group of the Italian Society of Pediatric Endocrinology Diabetology 《Human mutation》2005,25(1):22-27
Permanent neonatal diabetes mellitus (PNDM) is a rare condition characterized by severe hyperglycemia constantly requiring insulin treatment from its onset. Complete deficiency of glucokinase (GCK) can cause PNDM; however, the genetic etiology is unknown in most PNDM patients. Recently, heterozygous activating mutations of KCNJ11, encoding Kir6.2, the pore forming subunit of the ATP-dependent potassium (K(ATP)) channel of the pancreatic beta-cell, were found in patients with PNDM. Closure of the K(ATP) channel exerts a pivotal role in insulin secretion by modifying the resting membrane potential that leads to insulin exocytosis. We screened the KCNJ11 gene in 12 Italian patients with PNDM (onset within 3 months from birth) and in six patients with non-autoimmune, insulin-requiring diabetes diagnosed during the first year of life. Five different heterozygous mutations were identified: c.149G>C (p.R50P), c.175G>A (p.V59M), c.509A>G (p.K170R), c.510G>C (p.K170N), and c.601C>T (p.R201C) in eight patients with diabetes diagnosed between day 3 and 182. Mutations at Arg50 and Lys170 residues are novel. Four patients also presented with motor and/or developmental delay as previously reported. We conclude that KCNJ11 mutations are a common cause of PNDM either in isolation or associated with developmental delay. Permanent diabetes of non autoimmune origin can present up to 6 months from birth in individuals with KCNJ11 and EIF2AK3 mutations. Therefore, we suggest that the acronym PNDM be replaced with the more comprehensive permanent diabetes mellitus of infancy (PDMI), linking it to the gene product (e.g., GCK-PDMI, KCNJ11-PDMI) to avoid confusion between patients with early-onset, autoimmune type 1 diabetes. 相似文献
6.
Model for assessment of proficiency of human immunodeficiency virus type 1 sequencing-based genotypic antiretroviral assays
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Huang DD Bremer JW Brambilla DJ Palumbo PE Aldrovandi G Eshleman S Brown C Fiscus S Frenkel L Hamdan H Hart S Kovacs A Krogstad P LaRussa P Sullivan J Weinberg A Zhao YQ;Pediatric ACTG Sequencing Working Group 《Journal of clinical microbiology》2005,43(8):3963-3970
Use of sequencing-based genotyping as a diagnostic assay for human immunodeficiency virus (HIV) antiretroviral resistance is increasing. Periodic evaluation of the proficiency of laboratories performing this assay should be established. It is important to identify components of the assay that influence the generation of reliable sequencing data and that should and can be monitored. A model was developed to determine what parameters were reasonable and feasible for assessing the performance of genotyping assays. Ten laboratories using the genotyping platform, HIV-1 Genotyping System (HGS) v. 1 and software versions 1.1 or 2.0, participated in two rounds of testing. For each round, each group was sent a panel consisting of three clinical samples to sequence in real time. Six months later, seven laboratories using the TRUGENE HIV-1 Genotyping Kit participated in a separate round, working with both panels at the same time. Analysis of the data showed that one main indicator of genotyping proficiency was achievement of > or =98% sequence homology of a sample tested to a group consensus sequence for that sample. A second was concordant identification of codons at sites identified with resistance mutations in the sample, although scoring of these criteria is still undetermined from this study. These criteria are applicable to all sequence-based genotyping platforms and have been used as a baseline for assessing the performance of genotyping for the determination of antiretroviral resistance in our ongoing proficiency program. 相似文献
7.
Clinical,immunological, and molecular analysis in a large cohort of patients with X-linked agammaglobulinemia: an Italian multicenter study 总被引:5,自引:0,他引:5
Plebani A Soresina A Rondelli R Amato GM Azzari C Cardinale F Cazzola G Consolini R De Mattia D Dell'Erba G Duse M Fiorini M Martino S Martire B Masi M Monafo V Moschese V Notarangelo LD Orlandi P Panei P Pession A Pietrogrande MC Pignata C Quinti I Ragno V Rossi P Sciotto A Stabile A;Italian Pediatric Group for XLA-AIEOP 《Clinical immunology (Orlando, Fla.)》2002,104(3):221-230
A questionnaire-based retrospective clinical and immunological survey was conducted in 73 males with a definite diagnosis of X-linked agammaglobulinemia based on BTK sequence analysis. Forty-four were sporadic and 29 familial cases. At December 2000, the patients' ages ranged from 2 to 33 years; mean age at diagnosis and mean duration of follow-up were 3.5 and 10 years respectively. After the mid-1980s all but 2 were on intravenous immunoglobulin (IVIG) substitution therapy, with residual IgG >500 mg/dl in 94% of the patients at the time of enrollment. Respiratory infections were the most frequent manifestation both prior to diagnosis and over follow-up. Chronic lung disease (CLD) was present in 24 patients, in 15 already at diagnosis and in 9 more by 2000. The cumulative risk to present at diagnosis with CLD increased from 0.17 to 0.40 and 0.78 when the diagnosis was made at the ages of 5, 10, and 15 years respectively. For the 9 patients who developed CLD during follow-up, the duration of follow-up, rather than age at diagnosis; previous administration of intramuscular immunoglobulin; and residual IgG levels had a significant effect on the development of CLD. Chronic sinusitis was present in 35 patients (48%), in 15 already at diagnosis and in 20 by 2000. Sistemic infections such as sepsis and meningitis/meningoencephalitis decreased over follow-up, probably due to optimal protection provided by high circulating IgG levels reached with IVIG. 相似文献
8.
Increasing trend of Cesarean deliveries in HIV-infected women in the United States from 1994 to 2000
Dominguez KL Lindegren ML D'Almada PJ Peters VB Frederick T Rakusan TA Ortiz IR Hsu HW Melville SK Sadek R Fowler MG;Pediatric Spectrum of HIV Disease Consortium 《Journal of acquired immune deficiency syndromes (1999)》2003,33(2):232-238
BACKGROUND: Meta-analysis and randomized clinical trial results reported in June 1998 indicated a significant reduction in perinatal HIV transmission rates among mothers undergoing a cesarean section (C-section). OBJECTIVE: The objective of this study was to examine recent trends in and factors associated with C-section deliveries among HIV-infected women in the United States. DESIGN: A multisite pediatric medical record review of a cohort of HIV-exposed and HIV-infected infants in the Pediatric Spectrum of HIV Disease (PSD) Cohort study (n = 6467) and the national Pediatric HIV/AIDS Reporting System (HARS) (n = 8,306) was conducted. SETTING/PATIENTS: All infants born between 1994 and 2000 to HIV-positive mothers referred to the PSD study or to a Pediatric HARS hospital or clinic site were enrolled. RESULTS: The proportion of deliveries by C-section was steady at about 20% from 1994 through June 1998. From July 1998 through December 2000, this proportion increased to 44% in the PSD study and to nearly 50% in the Pediatric HARS. On analysis by multiple logistic regression, delivery of infants by C-section was associated with the release of study results (OR = 2.83), delivery in four PSD sites in reference to Texas (OR: 2.02-1.43), having private medical care reimbursement (OR = 1.62), and having maternal prenatal care (OR = 1.43). CONCLUSIONS: The PSD and Pediatric HARS data demonstrate a sharp increase in C-section rates mainly among HIV-infected women in the United States after the release of the meta-analysis and randomized clinical trial results in 1998. This finding highlights the rapid impact of study results on obstetric practice. It underscores the critical role of prenatal care in offering perinatal interventions such as scheduled C-section when indicated to reduce the likelihood of HIV transmission. 相似文献
9.
本文以小儿感冒为例介绍黎炳南教授运用解表法的经验。黎教授认为:小儿感冒以风邪为主要病因,不可与温病混同;治疗宜重在祛风,其中应重视使用善于发散的辛温药物,并注意温清调配;须据证选用升散或通降之法;对兼有阳气、阴血不足者,可以补散并用,补法中又以补益阳气为主。 相似文献
10.
目的 探讨核因子 κB(Nuclearfactor κB ,NF κB)在哮喘患儿气道炎症中的作用。方法 获得 9例哮喘患儿及 6例非哮喘对照的支气管粘膜 ,进行免疫组化及凝胶电泳迁移率检查 ,分别观察NF κB在支气管上皮细胞的表达及NF κB与DNA的结合活性。结果 NF κB在 9例哮喘患儿的支气管上皮细胞核均有表达 ;在 4例哮喘患儿中 (对 6例哮喘患儿进行了凝胶电泳迁移率检查 ) ,观察到NF κB与DNA结合。在 6例非哮喘对照患儿的支气管上皮细胞核均未见NF κB表达 ,也未见NF κB与DNA结合。结论 NF κB在哮喘患儿支气管上皮细胞活化 ,可能通过调控多种炎性蛋白的表达 ,导致气道炎症发生。 相似文献