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161.
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
162.
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
163.
Enzymically generated triplet carbonyl compounds transfer energy to the fluorescent state of flavins as shown by the suppression of the carbonyl chemiphosphorescence and concomitant appearance of the flavin fluorescence. A Stern-Volmer analysis including the effect of the collisional quenching by a diene indicates that the transfer occurs by a long range process.The present results open the way to “photobiology without light”. 相似文献
164.
M Haun M F Pereira M E Hoffmann A Joyas V Campos L D Filardi S L de Castro N Duran 《Biological research》1992,25(1):21-25
The biosynthetic pigment from Chromobacterium violaceum BB-78, 1,3-dihydro-2H-indol-2-one and its derivatives exhibit biological activities such as antimicrobial action, low hemolytic effects on red blood cells and in vitro trypanocide activity. A relatively high cytotoxicity on V-79 hamster fibroblast cells of the biosynthetic pigment was found, although with the methylol derivative the toxicity was almost eliminated. The methylol derivative exhibited similar toxicity as Nifurtimox, a known, commercial trypanocide compound. 相似文献
165.
166.
Marianne S. Jurkowitz-Alexander Ruth A. Altschuld Steven E. Haun Ralph E. Stephens† Lloyd A. Horrocks 《Journal of neurochemistry》1993,61(4):1581-1584
Abstract: Oligodendroglia-glioma hybrid cells (ROC-1) subjected to inhibition of glycolytic and oxidative ATP synthesis undergo a sequence of changes, including ATP depletion, parallel processes of cell swelling and blebbing, and finally plasma membrane disruption and cell death. The morphological and biochemical changes that follow ATP depletion were studied in the presence and absence of polyethylene glycol (M, 8,000), a nonpermeant oncotic agent. Polyethylene glycol prevented cell swelling and membrane blebbing. It significantly delayed, but did not prevent, the release of lactate dehydrogenase into the medium; it did not affect the fall in [ATP]. These results suggest that osmotic cell swelling may be a contributing factor in the loss of cell viability when ROC-1 cells are depleted of ATP. 相似文献