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251.
Achiléa Lisboa Bittencourt Washington Luiz C. dos Santos Cristina Haun de Oliveira 《Mycopathologia》1984,87(3):181-187
The authors present a case of intrauterine fetal infection by Candida, in an abortion of four months, associated with an I.U.D. In the placenta and adnexa we observed an acute inflammation consisting of extraplacental membranitis, omphalitis, chorio-amnionitis and choriovasculitis with a marked villitis and intervillitis. In the fetus, involvement of the skin, lungs and pharynx was observed.This case represents, probably the 15th reported instance of congenital fetal candidiasis, and the first case of a Candida hematogenic placental infection acquired from the fetal blood. The fetus undoubtedly acquired its infection by an ascending route, through the contamined amniotic fluid. 相似文献
252.
Marli Camassola Luciano Ramos De Bittencourt Nicole T. Shenem Jürgen Andreaus 《Biocatalysis and Biotransformation》2013,31(5-6):391-396
New cellulases from a strain of Penicillium echinulatum were characterized for their filter paper activity and β-glucosidase activity. Both activities showed maximum values between pH 4 and 5. With citrate buffer, activities were slightly higher than in acetate buffer of the same pH. Thermal stability of both activities was good up to 55°C. Filter paper activity was significantly reduced at higher temperatures. 相似文献
253.
Mitochondrial DNA variation and genetic structure in populations of Drosophila melanogaster 总被引:5,自引:0,他引:5
The understanding of the genetic structure of a species can be improved by
considering together data from different types of genetic markers. In the
past, a number of worldwide populations of Drosophila melanogaster have
been extensively studied for several such markers, including allozymes,
chromosomal inversions, and quantitative characters. Here we present
results from a study of restriction- fragment-length polymorphisms of
mitochondrial DNA (mtDNA) in 92 isofemale lines from many of the same
geographic populations of D. melanogaster. Eleven restriction enzymes were
used, of which four revealed restriction-site polymorphism. A total of 24
different haplotypes were observed, of which 18 were unique to single
populations. In many populations, the unique haplotypes have reached high
frequency without being observed in neighboring populations. A Wagner
parsimony tree reveals that mutationally close variants show geographical
clumping, suggesting local differentiation of mtDNA in populations. The
Old-World and the New-World populations are differentiated, with the
predominant Old-World haplotype being virtually absent from the New World.
These results contrast with those for the nuclear genes, in which many loci
show parallel clines in different continents, and suggest a common origin
of D. melanogaster populations in North America.
相似文献
254.
The molecular organization of the beta-globin complex of the deer mouse, Peromyscus maniculatus 总被引:1,自引:0,他引:1
Padgett RW; Loeb DD; Snyder LR; Edgell MH; Hutchison CA d 《Molecular biology and evolution》1987,4(1):30-45
Recombinant DNA clones have been isolated that contain 80 kb of the
beta-globin complex from the deer mouse, Peromyscus maniculatus.
Comparisons of this complex with that from the laboratory mouse, Mus
domesticus (with an order 5'-Hbby, Hbb-bhO, Hbb-bhl, Hbb-bh2, Hbb-bh3,
Hbb-bl, Hbb-b2 3') highlight organizational trends in the beta-globin
complex since the two species diverged. Unlike other mammals studied thus
far, the deer mouse possesses three adult genes. Partial sequence analysis
indicates that each of the three adult genes is intact and hence may be
functional. Hybridization of one of the two Mus pseudogenes, Hbb-bh3, to
genomic blots from Peromyscus reveals that it has a homologous counterpart
in Peromyscus. Homologous genes to the two gamma-like Mus genes, Hbb-bhO
and Hbb-bhl, are also found in Peromyscus. The strong hybridization between
the Hbb-bhl genes and significant nucleotide similarity between the Hbb-bhO
genes suggest that both pairs are important for the ontogeny of these mice
although no known product has been identified for the Hbb-bhO genes. The
presence of Hbb-bhO and Hbb-bhl in Peromyscus suggests that the duplication
that created this related gene set occurred before the two lineages
diverged. A single gene for Hbb-y has been isolated from Peromyscus. The
adult region in Peromyscus has undergone significant divergence from the
same region in Mus, having three rather than two adult genes, the
acquisition of at least 15 kb of extra DNA relative to Mus, and possibly
the loss of the Hbb-bh2 pseudogene. The nonadult region of the complex, in
contrast, contains the same set of genes apparently distributed over the
same amount of DNA as in the Mus beta- globin complex. This observation
suggests that the embryonic region of the complex is more evolutionarily
stable than the adult region.
相似文献
255.
Benelli Jéssica Louise Basso Rossana Patrícia Grafulha Talita Werner Poester Vanice Rodrigues Munhoz Lívia Silveira Martins Katheryne Benine Zogbi Heruza Einsfeld Von Groll Andrea Severo Cecília Bittencourt Stevens David A. Xavier Melissa Orzechowski 《Mycopathologia》2022,187(4):397-404
Mycopathologia - Opportunistic infections are serious complications in critically ill COVID-19 patients, especially co-infections with bacterial and fungal agents. Here we report a rare case of... 相似文献
256.
Diana Salles Sampaio Nelson Sabino Bittencourt Júnior Paulo Eugênio Oliveira 《Botanical journal of the Linnean Society. Linnean Society of London》2013,173(1):77-91
Apomixis and polyploidy have been important in the evolution of the angiosperms, and sporophytic apomixis has been associated with polyembryony and polyploidy in tropical floras. We studied the occurrence of polyembryony in populations of tetraploid Anemopaegma acutifolium, A. arvense and A. glaucum from the Brazilian cerrados, and histological features of sexual and apomictic processes were investigated in A. acutifolium. All populations and species were polyembryonic (68.9–98.4% of seeds). Normal double fertilization occurred in most ovules, with exceptions being that 3% of ovules were penetrated but not fertilized and in 4% of ovules both synergids were penetrated. The penetration of both synergids suggests a continuous attraction of pollen tubes and polyspermy. Adventitious embryo precursor cells (AEPs) arose from nucellar and integumental cells of the ovule in pollinated and unpollinated A. acutifolium, indicating sporophytic apomixis. However, further embryo and endosperm development required pollination and fertilization. This pseudogamy also allows concurrent sexual embryo development. Similar polyembryony rates and polyploidy indicated that A. arvense and A. glaucum are also apomictic, forming an agamic complex similar to that observed for some species of confamilial, but not closely related Handroanthus. The co‐occurrence of apomixis and polyploidy in different groups of Bignoniaceae indicates homoplasious origin of these agamic complexes. © 2013 The Linnean Society of London, Botanical Journal of the Linnean Society, 2013, 173 , 77–91. 相似文献
257.
A L Bittencourt L A de Freitas M L Pompeu M L Vieira A Barral 《Memórias do Instituto Oswaldo Cruz》1990,85(1):53-59
The authors investigated the relation between parasites and host-cells in active and regressed lesions of a patient with diffuse cutaneous leishmaniasis, evaluating the frequency of different cell types, and the location and integrity of amastigotes. No correlation was found between parasite integrity and size of parasitophorous vacuoles. They observed ultrastructural findings characterizing a cell mediated immune response: macrophages lysis, parasitic destruction inside macrophages, close contact between parasitized macrophages and lymphocytes and between parasites and lymphocytes, lymphocytic infiltration and fibrosis. They suggest that in DCL there is a limited cellular immune response, although insufficient to control infection. 相似文献
258.
Sartori Rafaela Basso Siqueira Stefania Fortes Maroneze Mariana Manzoni Fagundes Mariane Bittencourt Wagner Roger Zepka Leila Queiroz Jacob-Lopes Eduardo 《Journal of applied phycology》2021,33(3):1457-1472
Journal of Applied Phycology - Microalgae produce many metabolites with diversified structures that play important roles in their development. This work evaluated the effects of different climatic... 相似文献
259.
Sharon LR Simon Lise Lamoureux Margot Plews Michael Stobart Jillian LeMaistre Ute Ziegler Catherine Graham Stefanie Czub Martin Groschup J David Knox 《Proteome science》2008,6(1):23
Background
The bovine spongiform encephalopathy (BSE) epidemic and the emergence of a new human variant of Creutzfeldt-Jakob Disease (vCJD) have led to profound changes in the production and trade of agricultural goods. The rapid tests currently approved for BSE monitoring in slaughtered cattle are all based on the detection of the disease related isoform of the prion protein, PrPd, in brain tissue and consequently are only suitable for post-mortem diagnosis. Objectives: In instances such as assessing the health of breeding stock for export purposes where post-mortem testing is not an option, there is a demand for an ante-mortem test based on a matrix or body fluid that would permit easy access and repeated sampling. Urine and urine based analyses would meet these requirements. 相似文献260.