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Vieira Mde L Singh RP Derendorf H 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》2010,878(29):2967-2973
A specific and reliable HPLC-PDA method for the quantitative determination of triamcinolone acetonide, budesonide and fluticasone propionate (as internal standards) in small volumes of microdialysate and rat plasma was developed. An efficient solid-phase extraction (SPE) procedure for plasma samples yielded extremely clean extracts with overall recovery of 104.3% and 95.7% for triamcinolone acetonide (TA) and fluticasone propionate, respectively. Plasma extracts obtained after SPE and microdialysis samples were directly injected on a C18 column to separation. The method has been validated with good linearity, sensitivity, specificity and high accuracy (RE -5.28% to 9.14%) and precision (CV 0.50% to 6.62%) on both matrices. In stability studies, TA and budesonide were stable during storage and assay procedures. The method was applied to a pharmacokinetic study in rodents using microdialysis to determine protein unbound TA concentrations in blood and muscle. 相似文献
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Valente F Lago BV Castro CA Almeida AJ Gomes SA Soares CC 《Memórias do Instituto Oswaldo Cruz》2010,105(8):970-977
An estimated 360 million people are infected with hepatitis B virus (HBV) worldwide. Among these, 65 million live in Africa. Despite the high levels of hepatitis B in Africa, HBV epidemiology is still poorly documented in most African countries. In this work, the epidemiological and molecular characteristics of HBV infection were evaluated among the staff, visitors and adult patients (n = 508) of a public hospital in Luanda, Angola. The overall prevalence of hepatitis B core antibody (anti-HBc) and hepatitis B surface antigen was 79.7% and 15.1%, respectively. HBV infection was higher in males and was more prevalent in individuals younger than 50 years old. HBV-DNA was detected in 100% of HBV "e" antigen-positive serum samples and in 49% of anti-hepatitis Be antibody-positive samples. Thirty-five out of the 40 HBV genotypes belonged to genotype E. Circulation of genotypes A (4 samples) and D (1 sample) was also observed. The present study demonstrates that HBV infection is endemic in Luanda, which has a predominance of genotype E. This genotype is only sporadically found outside of Africa and is thought to have emerged in Africa at a time when the trans-Atlantic slave trade had stopped. 相似文献
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Ana R Seabra Cristina P Vieira Julie V Cullimore Helena G Carvalho 《BMC plant biology》2010,10(1):183
Background
Nitrogen is a crucial nutrient that is both essential and rate limiting for plant growth and seed production. Glutamine synthetase (GS), occupies a central position in nitrogen assimilation and recycling, justifying the extensive number of studies that have been dedicated to this enzyme from several plant sources. All plants species studied to date have been reported as containing a single, nuclear gene encoding a plastid located GS isoenzyme per haploid genome. This study reports the existence of a second nuclear gene encoding a plastid located GS in Medicago truncatula. 相似文献157.
Deyze Alencar Soares Rosângela Vieira de Andrade Simoneide Sousa Silva Anamélia Lorenzetti Bocca Sueli Maria Soares Felipe Silvana Petrofeza 《BMC microbiology》2010,10(1):241
Background
Phospholipase B (PLB) has been reported to be one of the virulence factors for human pathogenic fungi and has also been described as necessary for the early events in infection. Based on these data, we investigated the role of PLB in virulence and modulation of the alveolar pulmonary immune response during infection using an in-vitro model of host-pathogen interaction, i.e. Paracoccidioides brasiliensis yeast cells infecting alveolar macrophage (MH-S) cells. 相似文献158.
Janaína A Couto Karina LA Saraiva Cleiton D Barros Daniel P Udrisar Christina A Peixoto Juliany SB César Vieira Maria C Lima Suely L Galdino Ivan R Pitta Maria I Wanderley 《Reproductive biology and endocrinology : RB&E》2010,8(1):13
Background
The present study was designed to examine the effect of chronic treatment with rosiglitazone - thiazolidinedione used in the treatment of type 2 diabetes mellitus for its insulin sensitizing effects - on the Leydig cell steroidogenic capacity and expression of the steroidogenic acute regulatory protein (StAR) and cholesterol side-chain cleavage enzyme (P450scc) in normal adult rats. 相似文献159.
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The secreted glycoprotein vascular endothelial growth factor A (VEGF or VEGFA) affects many different cell types and modifies a wide spectrum of cellular behaviors in tissue culture models, including proliferation, migration, differentiation and survival. The versatility of VEGF signaling is reflected in the complex composition of its cell surface receptors and their ability to activate a variety of different downstream signaling molecules. A major challenge for VEGF research is to determine which of the specific signaling pathways identified in vitro control development and homeostasis of tissues containing VEGF-responsive cell types in vivo. 相似文献