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161.
Emerging reports have associated chronic pulmonary obstructive disease (COPD) with invasive aspergillosis (IA), particularly in patients treated with mechanical ventilation and/or corticosteroids. This is a multicentre study in which COPD patients demonstrating a new lung infiltrate while being mechanically ventilated were prospectively evaluated for the presence of IA. From the 47 patients studied, Aspergillus fumigatus was recovered in culture in two patients (4.2%). While serum galactomannan (GM) was negative for 94% of patients, GM levels in respiratory samples were >0.5, >1.0 and >1.5 for 74.5, 40.5, and 21.3% of patients, respectively. PCR was positive for 10 patients in the study but did not differentiate Aspergillus colonization from infection. The combination of PCR and GM in respiratory samples may be an interesting alternative to diagnose IA in COPD patients.  相似文献   
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ABSTRACT: BACKGROUND: Dengue is the most important mosquito-borne viral disease worldwide. Dengue virus comprises four antigenically related viruses named dengue virus type 1 to 4 (DENV1-4). DENV-3 was re-introduced into the Americas in 1994 causing outbreaks in Nicaragua and Panama. DENV-3 was introduced in Brazil in 2000 and then spread to most of the Brazilian States, reaching the neighboring country, Paraguay in 2002. In this study, we have analyzed the phylogenetic relationship of DENV-3 isolated in Brazil and Paraguay with viruses isolated worldwide. We have also analyzed the evolutionary divergence dynamics of DENV-3 viruses. RESULTS: The entire open reading frame (ORF) of thirteen DENV-3 isolated in Brazil (n= 9) and Paraguay (n= 4) were sequenced for phylogenetic analysis. DENV-3 grouped into three main genotypes (I, II and III). Several internal clades were found within each genotype that we called lineage and sub-lineage. Viruses included in this study belong to genotype III and grouped together with viruses isolated in the Americas within the lineage III. The Brazilian viruses were further segregated into two different sub-lineage, A and B, and the Paraguayan into the sub-lineage B. All three genotypes showed internal grouping. The nucleotide divergence was in average 6.7% for genotypes, 2.7% for lineages and 1.5% for sub-lineages. Phylogenetic trees constructed with any of the protein gene sequences showed the same segregation of the DENV-3 in three genotypes. CONCLUSION: Our results showed that two groups of DENV-3 genotypes III circulated in Brazil during 2002-2009, suggesting different events of introduction of the virus through different regions of the country. In Paraguay, only one group DENV-3 genotype III is circulating that is very closely related to the Brazilian viruses of sub-lineage B. Different degree of grouping can be observed for DENV-3 and each group showed a characteristic evolutionary divergence. Finally, we have observed that any protein gene sequence can be used to identify the virus genotype.  相似文献   
164.
Two parrot species, Amazona amazonica and A. aestiva, submitted to cytogenetic analysis presented a diploid chromosome number of 2n=70 (20M+50m). With the C-banding pattern, the cells of female speciments showed an almost totally heterochromatic W chromosome. No chromosome differences were observed in the two species studied.  相似文献   
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In studies performed during 1986, 1987, 1990, and 1991, in the seasonally flooded forest of the Napo and Nanay river basin, we recorded seven instances of cohabitation in night monkeys,Aotus vociferans. Cohabitation refers to the sharing of a sleeping site of one species of animal with other different species of animals (Aquino & Encarnacion, 1986). We also recorded two instances of cooccupation of night monkeys with other species of nocturnal mammals. Cooccupation refers to the independent use of different sleeping sites within the same tree by two or more species of animals. This study is the first report of cooccupation within the generaAotus. Forty-five sleeping trees with entrance holes were used by the night monkeys. In addition, one sleeping site was observed in a small concavity of the foliar sheath on aMauritia flexuosa palm.  相似文献   
166.
The observation of remarkable karyotypic variation in owl monkeys (Aotus trivirgatus) stimulated us to study the chromosomal evolution of this New World genus. As an extension of this project, we examined the chromosome complement of a “phenotype-B” Aotus population from Peru. In addition to karyotype V(2n = 46), two new karyotypes with diploid numbers of 47 and 48 were identified. A G-band comparison of these karyotypes indicated that the chromosome number polymorphism in these Peruvian owl monkeys resulted from a single fusion or fission event involving a single metacentric and two acrocentric chromosome pairs. This mechanism is also known to be responsible for the chromosome number polymorphism in at least two other populations of phenotype B Aotus, one from Colombia and the other from Panama.  相似文献   
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The main purpose of this article is to show the application of the CG/C/IRMS in real time during competition in the steroid confirmation analysis. For this reason, this paper summarizes the results obtained from the doping control analysis during the period of the 2007 Pan American Games held in Rio de Janeiro, Brazil. Approximately 5600 athletes from 42 different countries competed in the games. Testing was performed in accordance to World Anti-Doping Agency (WADA) technical note for prohibited substances. This paper reports data where abnormal urinary steroid profiles, have been found with the screening procedures. One 8 mL urine sample was used for the analysis of five steroid metabolites with two separate analyses by gas chromatography/combustion/isotope ratio mass spectrometry (GC/C/IRMS). Urine samples were submitted to GC/C/IRMS for confirmation analysis to determine the 13C/12C ratio of selected steroids. Fifty-seven urine samples were analyzed by GC/C/IRMS and the δ 13C values (‰) of androsterone, etiocholanolone, 5β-androstane-3α, 17β-diol (5β-diol), 5α-androstane-3α, 17β-diol (5α-diol) and 5β-pregnane-3α, 20α-diol (5β-pdiol), the endogenous reference compound are presented. One urine sample with a testosterone/epitestosterone (T/E) ratio of 4.7 was confirmed to be positive of doping by GC/C/IRMS analysis. The δ values of 5β-diol and 5α-diol were 3.8 and 10.8, respectively, compared to the endogenous reference compound 5β-pdiol, which exceeded the WADA limit of 3‰. The results obtained by CG/C/IRMS confirmation analyses, in suspicious samples, were conclusive in deciding whether or not a doping steroid violation had occurred.  相似文献   
170.
A series of 4,4-disubstituted cyclohexylamine based CCR5 antagonists has been designed and synthesized. Their antiviral structure–activity relationship has been extensively explored.  相似文献   
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