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BACKGROUND: The initial rate of plasma HIV-1 RNA (pVL) decline has been proposed as a marker of early efficacy of antiretroviral therapy (ART) and a possible predictor of late efficacy. We compared the rate of pVL decline in patients starting ART with nevirapine (NVP), efavirenz (EFV), or both drugs combined in addition to lamivudine (3TC) and stavudine (d4T). METHODS: Analysis of the viral decay constant (VDc) during the first 2 weeks of treatment in patients enrolled in the 2NN study who remained on allocated treatment. RESULTS: The median VDc (log10 copies per day, [interquartile range]) was similar for NVP (0.30 [0.25-0.36], EFV (0.31 [0.27-0.37]), and NVP + EFV (0.30 [0.27-0.36]). Patients with a baseline pVL >100,000 copies/mL were 8.7 (95% confidence interval [CI]: 6.2-12.3) times more likely to have a VDc >75th percentile. A high VDc was not associated with plasma drug concentration or with a decreased risk of virologic failure at week 48 after the start of therapy (hazard ratio = 0.8, 95% CI: 0.6-1.2). CONCLUSION: NVP, EFV, or NVP + EFV in combination with 3TC and d4T show similar rates of pVL decline during the first 2 weeks of treatment. The VDc with these regimens is not predictive of late virologic efficacy.  相似文献   
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The human serum protein transthyretin (TTR) is highly fibrillogenic in vitro and is the fibril precursor in both autosomal dominant (familial amyloidotic polyneuropathy [FAP] and familial amyloidotic cardiomyopathy [FAC]) and sporadic (senile systemic amyloidosis [SSA]) forms of human cardiac amyloidosis. We have produced mouse strains transgenic for either wild-type or mutant (TTRLeu55Pro) human TTR genes. Eighty-four percent of C57BI/6xDBA/2 mice older than 18 months, transgenic for the wild-type human TTR gene, develop TTR deposits that occur primarily in heart and kidney. In most of the animals, the deposits are nonfibrillar and non-Congophilic, but 20% of animals older than 18 months that bear the transgene have human TTR cardiac amyloid deposits identical to the lesions seen in SSA. Amino terminal amino acid sequence analysis and mass spectrometry of the major component extracted from amyloid and nonamyloid deposits revealed that both were intact human TTR monomers with no evidence of proteolysis or codeposition of murine TTR. This is the first instance in which the proteins from amyloid and nonfibrillar deposits in the same or syngeneic animals have been shown to be identical by sequence analysis. It is also the first time in any form of amyloidosis that nonfibrillar deposits have been shown to systematically occur temporally before the appearance of fibrils derived from the same precursor in the same tissues. These findings suggest, but do not prove, that the nonamyloid deposits represent a precursor of the fibril. The differences in the ultrastructure and binding properties of the deposits, despite the identical sizes and amino terminal amino acid sequences of the TTR and the dissociation of deposition and fibril formation, provide evidence that in vivo factors, perhaps associated with aging, impact on both systemic precursor deposition and amyloid fibril formation.  相似文献   
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Cells of the impulse-generating and conducting tissues of the insect-eating bat Pipistrellus pipistrellus were studied and evaluated using ultrastructural morphometry. Sinoatrial node cells are smaller than working atrial cells and measure about 6.5 microm in diameter. Their mitochondira and myofibril content constitute 23% and 19% of cytoplasmic volume, respectively. Corresponding values for working atrial cells are 23% and 52%. Atrioventricular node cells are 4.2 microm in diameter and contain abundant glycogen in the cytoplasm. The fractional volume of mitochondria in about 24% while that of myofibrils is 7%. Cells of the bundle of His are larger (6-8 microm diameter) and contain more cellular organelles than do nodal cells. Their mitochondria and myofibril contents are 25% and 25%, respectively. Cells in the proximal part of the right bundle branch are slender with diameters averaging 3.4 microm. Mitochondrial content is 23% while myofibrils occupy 20% of the cytoplasmic volume of these cells. Distally located bundle branch cells measure 7-10 microm in diameter with mitochondria and myofibril volumes of 30% and 33%. Subendocardial cells in the ventricular free wall are large reaching 28 microm in diameter (cf. 14-18 microm in working ventricular cells) and have mitochondira and myofibril volume fractions of 32% and 29%, respectively (35% & 40% for working ventricular cells).  相似文献   
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Autoimmune thyroid disease (AITD) is an inflammatory thyroiditis that in some cases is characterized by lymphocytic infiltration of the thyroid gland, also referred to as chronic lymphocytic thyroiditis or Hashimoto thyroiditis. Hashimoto thyroiditis is one of the commonest causes of hypothyroidism. Hypothyroidism has been associated with osteoarthritis (OA) and inflammatory forms of arthritis and with several well defined connective tissue diseases, which in turn can cause arthritis. The presence of arthritis in patients with AITD with normal thyroid function is now being increasingly recognized. There is also considerable evidence to suggest that AITD is highly associated with fibromyalgia syndrome. We review the current literature on the rheumatologic manifestations of AITD and describe the features in its presentation that set it apart from other forms of autoimmune arthritis.  相似文献   
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1. The effect of heparin and related glycosaminoglycans on bovine airway smooth muscle proliferation has been investigated. 2. Foetal bovine serum stimulated division of bovine trachealis smooth muscle cells in a concentration-dependent fashion at concentrations between 1 and 30%. 3. Heparin (0.1-100 micrograms ml-1), heparan sulphate (0.1-100 micrograms ml-1) and fragmin (0.1-100 micrograms ml-1) inhibited smooth muscle division in a concentration-dependent fashion between 0.1-100 micrograms ml-1. A heparin disaccharide did not exhibit inhibition of division at 100 micrograms ml-1. 4. Dextran sulphate at molecular weights of 5 x 10(3) and 5 x 10(5) concentration-dependently inhibited division between 0.1-100 micrograms ml-1. Dextran without sulphation did not exhibit inhibition of division at 100 micrograms ml-1. 5. The magnitude of inhibition of proliferation did not reach 100% for any compounds examined at concentrations up to 100 micrograms ml-1 during incubations for 5 and 14 days. IC50 values for inhibition of proliferation ranged between 1-5 micrograms ml-1. 6. These findings suggest that heparin and related glycosaminoglycans inhibit bovine airway smooth muscle cell division.  相似文献   
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目的:探讨寻找干细胞移植治疗急性心肌梗死的最佳移植治疗时间,指导临床应用,提高临床疗效。方法:应用计算机检索medline2000-01/2006-05文章,检索词为:"stem cell transplantation and/or acute myocardialinfarction(AMI)and/or chronic heart failure or ischemic cardiomyopathy",限定文章语言种类为English;同时计算机检索中国期刊全文数据库,相同时间的文章,检索词:"干细胞移植治疗,干细胞移植与急性心肌梗死,干细胞移植治疗与心力衰竭或慢性缺血性心肌病",限定文章语言种类为中文。共检索到300余篇与主题有关的文献,其中12篇有价值的文章见参考文献。移植时间取平均值,并按射血分数值和P值进行列表、作图。对干细胞移植时间与射血分数值之间的关系进行分析。结果:在急性心肌梗死后2~5d和9d以后进行干细胞移植治疗疗效较24h内及6~8d为好。结论:干细胞移植治疗急性心肌梗死的移植时间与临床疗效之间可能存在一定的相关性。经冠脉注入干细胞比经静脉或经心内膜下注入可以更好地改善左室功能,但还需要进一步的临床资料证实。  相似文献   
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