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41.
Yip  Ronald ML  Cheung  Tommy T  So  Ho  Chan  Julia PS  Ho  Carmen TK  Tsang  Helen HL  Yu  Carrel KL  Wong  Priscilla CH 《Clinical rheumatology》2023,42(8):2013-2027
Clinical Rheumatology - Gout is one of the most common noncommunicable diseases in Hong Kong. Although effective treatment options are readily available, the management of gout in Hong Kong remains...  相似文献   
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ABSTRACT. In general, prostanoids act as local mediators, not as circulating hormones. A specific exception to this rule is the infusion of prostaglandin E1 in patients with ductus arteriosus-depend-ent pulmonary or systemic blood flow associated with congenital heart disease. We therefore measured prostaglandin E, plasma levels by gas chromatography-mass spectrometry during effective infusion of prostaglandin E1 in 10 neonates. Prostaglandin E1 plasma levels ranged from 22 to 530 (median 56) pg/ml in these patients. Since prostaglandin E1 is not synthesized endogenously to any significant extent, these plasma concentrations constitute genuine circulating levels not confounded by the common problem of e vivo artifacts. If endogenous prostanoids (e.g. prostaglandin E2) are suspected as circulating mediators, plasma levels detected by reliable methods ought to be in the same range as prostaglandin E1 plasma levels in the present investigation.  相似文献   
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Reports on the influence of inhaled glucocorticoids on growth have been controversial. We studied the growth of prepubertal asthmatic children prior to and during glucocorticoid therapy. We collected retrospectively the notes of 201 asthmatic children aged 1–11 years receiving inhaled beclomethasone dipropionate or budesonide. We calculated their height and height velocity standard deviation scores (HSDS and HVSDS, respectively) before the treatment and up to 5 years during the treatment and compared those with the growth of healthy peers. The dose of the medication was calculated and the severity of asthma was assessed. The asthmatic children grew similarly to their healthy peers before treatment with inhaled glucocorticoids: the mean HSDS was +0.02 and the mean HVSDS +0.01 for boys and -0.16 and +0.13 for girls, respectively. Growth retardation took place soon after the start of the treatment, the most profound decrease in the growth velocity (the change in the mean HVSDS from +0.05 to -0.88) occurring during the first year of treatment. The growth-retarding effect of inhaled glucocorticoids was not dose dependent. In the covariance analysis the increasing severity of asthma had a significant interaction with repeated measurements, showing more growth retardation along with more severe asthma, especially during long-term treatment. Asthma per se does not impair growth, but inhaled glucocorticoids may do so. Careful monitoring of the growth of all asthmatic children receiving inhaled glucocorticoids is necessary because the growth-retarding effect of the medication is not dose dependent. Individual sensitivity might explain the differences seen in the growth patterns of children receiving inhaled glucocorticoids.  相似文献   
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BACKGROUND: Recently, new immunoblot assays for the detection of antibodies to hepatitis C virus (HCV) became available. STUDY DESIGN AND METHODS: The performance of five confirmatory anti-HCV immunoblot assays was studied with samples with known HCV antibody and HCV RNA status. The assays were a third-generation strip recombinant immunoblot assay (RIBA-3, Chiron Corp., Emeryville, CA), a second-generation HCV blot (DB-2 blot, Diagnostic Biotechnology, Singapore), the Wellcozyme HCV Western blot (Murex blot, Murex Diagnostics, Dartford, UK), an immunodot HCV assay (Matrix, Abbott Laboratories, Chicago, IL), and the third-generation HCV line immunoassay (Liatek-III, Organon Teknika, Boxtel, The Netherlands). RESULTS: Sensitivity on samples from 48 HCV RNA-positive, second-generation RIBA (RIBA-2)-positive persons and specificity on samples from 31 low-risk donors was 96 percent or better for all assays. The sensitivity on 31 HCV RNA-positive, RIBA-2- indeterminate samples was as follows: Liatek-III, 94 percent; RIBA-3, 90 percent; Murex blot, 61 percent; Matrix, 55 percent; and DB-2 blot, 39 percent. In testing 39 HCV RNA-negative, RIBA-2-indeterminate donor samples, the percentage found to be negative was Liatek-III, 77 percent; RIBA-3, 67 percent; Murex blot, 49 percent; DB-2 blot, 33 percent; and Matrix, 15 percent. The order of sensitivity on four HCV seroconversion series was (from high to low): RIBA-3, Liatek-III, DB-2 blot, Murex blot, and Matrix; the differences were small. CONCLUSION: Detection of HCV antibodies was not refined by the addition of new HCV antigens (NS5, E2/NS1), but by improved classical antigens (core, NS3, NS4). Replacement of the commonly used RIBA-2 will resolve the status of a high proportion of RIBA-2-indeterminate samples.  相似文献   
47.
胃癌雌激素受体的研究   总被引:1,自引:3,他引:1  
自20世纪60年代发现雌激素受体以来,学者们开展了对各种不同器官肿瘤受体的研究,并形成了激素作用机制的3种模式(二步模式、核模式和平衡模式).目前已在众多的肿瘤中发现了性激素受体,如孕酮激素(PR)、雌激素(ER)和雄激素(AR).这些肿瘤包括激素依赖性器官和非依赖性器官的肿瘤.  相似文献   
48.
CD11b is the alpha chain of the Mac-1 integrin and is preferentially expressed in myeloid cells (neutrophils, monocytes, and macrophages). We have previously shown that the CD11b promoter directs cell-type- specific expression in myeloid lines using transient transfection assays. To confirm that these promoter sequences contain the proper regulatory elements for correct myeloid expression of CD11b in vivo, we have used the -1.7-kb human CD11b promoter to direct reporter gene expression in transgenic mice. Stable founder lines were generated with two different reporter genes, a Thy 1.1 surface marker and the Escherichia coli lacZ (beta-galactosidase) gene. Analysis of founders generated with each reporter demonstrated that the CD11b promoter was capable of driving high levels of transgene expression in murine macrophages for the lifetime of the animals. Similar to the endogenous gene, transgene expression was preferentially found in mature monocytes, macrophages, and neutrophils and not in myeloid precursors. These experiments indicate that the -1.7 CD11b promoter contains the regulatory elements sufficient for high-level macrophage expression. This promoter should be useful for targeting heterologous gene expression to mature myeloid cells.  相似文献   
49.
To elucidate the molecular basis of band 3 deficiency in a recently defined subset of patients with autosomal dominant hereditary spherocytosis (HS), we screened band 3 cDNA for single-strand conformation polymorphism (SSCP). In 5 of 17 (29%) unrelated HS subjects with band 3 deficiency, we detected substitutions R760W, R760Q, R808C, and R870W that were all coinherited with the HS phenotype. The involved arginines are highly conserved throughout evolution. To examine whether or not the product of the mutant allele is inserted into the membrane, we studied one HS subject who was doubly heterozygous for the R760Q mutation and the K56E (band 3sMEMPHIS) polymorphism that results in altered electrophoretic mobility of the band 3 Memphis proteolytic fragments. We detected only the band 3MEMPHIS in the erythrocyte membrane indicating that the protein product of the mutant, R760Q, band 3 allele is absent from the red blood cell membrane. These findings suggest that the R760Q substitution, and probably the other arginine subsitutions, produce band 3 deficiency either by precluding incorporation of the mutant protein into the red blood cell membrane or by leading to loss of mutant protein from differentiating erythroid precursors.  相似文献   
50.
Kenney  RT; Malech  HL; Epstein  ND; Roberts  RL; Leto  TL 《Blood》1993,82(12):3739-3744
The genetic defect in the p67phox-deficient form of chronic granulomatous disease (CGD) follows an autosomal recessive pattern of inheritance. When genomic DNA from normal individuals is digested with HindIII and probed with p67phox cDNA an allelic restriction fragment length polymorphism (RFLP) of 4.0 kb or 2.3 kb is detected. We cloned and characterized the p67phox gene using the cDNA and sequenced the exon/intron boundaries, mapping 16 exons on the 40-kb gene. The polymorphic region was then sequenced to identify the inheritance pattern of amniocentesis-derived fetal cells by genomic amplification. The proband, a 9-year-old female patient with p67phox-deficient CGD, and her phenotypically normal mother are homozygous for the RFLP marker, whereas the father and two brothers are heterozygous. The fetus was shown to be heterozygous as well, showing it had inherited at least one normal p67phox gene from the father and that it was predicted to have a normal phenotype. Cord blood samples at birth showed normal oxidative function. Amplification allows rapid detection of the inheritance pattern for fetal diagnosis in informative families. We report the genomic structure of p67phox and an amplification-based method for detection of the marker on chromosome 1q25, used here for prenatal diagnosis of CGD.  相似文献   
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