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71.
Systematic Parasitology - Isospora parnaitatiaiensis Silva, Rodrigues, Lopes, Berto, Luz, Ferreira & Lopes, 2015 was identified from a new host, the plain antvireo Dysithamnus mentalis...  相似文献   
72.
Ten microsatellite loci were developed and described for Pimelodus microstoma, identified in eggs collected from the lower Das Cinzas river. Nine loci were polymorphic, with 02–19 alleles per locus. The observed heterozygosity values were up to 0.898. Five species of the Pimelodidae family were also tested for amplification of loci, among which Pimelodus maculatus was the most successful in the transferability of primers. These loci have proven to be useful for studying the variability and structuring of populations of Pimelodus microstoma.  相似文献   
73.
Plant and Soil - Aggressive ruderal plant species pose an increasing problem in anthropically degraded lands. They both affect and are affected by other vegetation and by soil fertility in their...  相似文献   
74.
Hemigrammus xaveriellus sp. nov. is described from the upper Río Vaupés basin (Amazon basin), Departamento Guaviare, Colombia. It is distinguished from all congeners by the combination of the following characters: presence of a conspicuous, dark, longitudinal midlateral stripe extending along the body; presence of a conspicuous rounded, horizontally elongated humeral blotch anterior to the beginning of the dark midlateral stripe; seven scale rows between the dorsal fin and lateral line (vs. five to six); and five scale rows between the lateral line and pelvic-fin insertion (vs. three to four). The single mature male of He. xaveriellus possessed a well-developed urogenital papilla, an unusual feature among characids. The presence of an enlarged urogenital papilla in the family is discussed, and comments regarding the putative relationships of the new species are presented.  相似文献   
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76.

Familial hypercholesterolemia (FH) is an autosomal dominant genetic disease characterized by high levels of low-density lipoprotein-cholesterol (LDLc), associated to premature cardiovascular disease. The detection of the variants related to FH is important to improve the early diagnosis in probands / index-cases (ICs) and their relatives. We included ICs with FH and their relatives, living in a small region of Minas Gerais state-Brazil, which were classified according to Dutch Lipid Clinic Network Criteria (DLCNC) and submitted to sequencing of genes related to FH (LDLR, APOB, PCSK9, LDLRAP1, LIPA, STAP1, APOE, ABCG5 e ABCG8). In a total of 143 subjects (32 ICs and 111 relatives), eight variants were identified in 91 individuals. From these variants, five were in LDLR [p.(Asp224Asn), p.(Ser854Gly), p.(Cys34Arg), p.(Asp601His), deletion of exon15 in LDLR)], one in APOB [p.(Met499Val)], one in PCSK9 [p.(Arg237Trp)] and one in APOE [p.(Pro28Leu)] genes. The variants were detected in 100% of those subjects classified as definitive, 87% as probable and 69% as possible FH cases based on DLCNC. The LDLc level was higher in individuals with corneal arch and xanthomas or xanthelasmas, as well as in pathogenic or probably pathogenic variants carriers. This study showed higher frequency of LDLR gene variants compared to other genes related to LDL metabolism in individuals with FH in Minas Gerais – Brazil and the presence of FH in relatives without previous diagnosis. Our data reinforce the importance of molecular and clinical evaluation of FH relatives in order to early diagnosis the FH, as well as cardiovascular diseases prevention.

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77.
The first-line chemotherapy treatment for Glioblastoma (GBM) - the most aggressive and frequent brain tumor - is temozolomide (TMZ). The Sonic hedgehog (SHH) pathway is involved with GBM tumorigenesis and TMZ chemoresistance. The role of SHH pathway inhibition in the potentiation of TMZ's effects using T98G, U251, and GBM11 cell lines is investigated herein. The combination of GANT-61 and TMZ over 72 hr suggested a synergistic effect. All TMZ-resistant cell lines displayed a significant decrease in cell viability, increased DNA fragmentation and loss of membrane integrity. For T98G cells, G2/M arrest was observed, while U251 cells presented a significant increase in reactive oxygen species production and catalase activity. All the cell lines presented acidic vesicles formation correlated to Beclin-1 overexpression. The combined treatment also enhanced GLI1 expression, indicating the presence of select resistant cells. The selective inhibition of the SHH pathway potentiated the cytotoxic effect of TMZ, thus becoming a promising in vitro strategy for GBM treatment.  相似文献   
78.
Hyphessobrycon chiribiquete n. sp. is described from the Río Caquetá drainage in Colombia and the Río Ucayali drainage in Peru, western Amazon. The new species is diagnosed from its congeners by having the following combination of characters: a conspicuous narrow midlateral stripe, starting on the sides of the body behind the opercle near the lateral line; lateral stripe overlapped anteriorly with a vertically elongated humeral blotch; inner premaxillary teeth pentacuspid; margin of anal fin falcate in mature males.  相似文献   
79.
Ribosomal subunit biogenesis in eukaryotes is a complex multistep process. Mrd1 is an essential and conserved small (40S) ribosomal subunit synthesis factor that is required for early cleavages in the 35S pre-ribosomal RNA (rRNA). Yeast Mrd1 contains five RNA-binding domains (RBDs), all of which are necessary for optimal function of the protein. Proteomic data showed that Mrd1 is part of the early pre-ribosomal complexes, and deletion of individual RBDs perturbs the pre-ribosomal structure. In vivo ultraviolet cross-linking showed that Mrd1 binds to the pre-rRNA at two sites within the 18S region, in helix 27 (h27) and helix 28. The major binding site lies in h27, and mutational analyses shows that this interaction requires the RBD1-3 region of Mrd1. RBD2 plays the dominant role in h27 binding, but other RBDs also contribute directly. h27 and helix 28 are located close to the sequences that form the central pseudoknot, a key structural feature of the mature 40S subunit. We speculate that the modular structure of Mrd1 coordinates pseudoknot formation with pre-rRNA processing and subunit assembly.  相似文献   
80.
Galactomannan (GM) was recently included in consensus guidelines as an indirect mycological criterion for the diagnosis of invasive aspergillosis. Currently, there is an enzyme immunoassay available to detect GM in biological samples, the Platelia? Aspergillus EIA. In this study, the reproducibility of positive results obtained using this assay was evaluated using serum samples from neutropenic patients. A trend toward lower values was observed, and 55 %(27/49) of positive results were negative after retesting. A low reproducibility of positive results for the detection of GM in serum was observed.  相似文献   
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