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Type-restricted neutralization of molecular clones of human immunodeficiency virus 总被引：23，自引：0，他引：23
D J Looney A G Fisher S D Putney J R Rusche R R Redfield D S Burke R C Gallo F Wong-Staal 《Science (New York, N.Y.)》1988,241(4863):357-359
In a study of the immunologic significance of the genetic diversity present within single isolates of human immunodeficiency virus type 1 (HIV-1), the neutralization of viruses derived from molecular clones of the HIV-1 strain HTLV-IIIB by an extensive panel of sera was compared. Sera from HIV-1-infected patients and from goats immunized with polyacrylamide gel-purified HIV-1 envelope glycoprotein (gp120), native gp120, or gp120-derived recombinant peptides, showed marked heterogeneity in neutralizing activity against these closely related viruses. The change of a single amino acid residue in gp120 may account for such "clonal restriction" of neutralizing activity. 相似文献
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Serum hepatitis antigen (SH): rapid detection by high voltage immunoelectroosmophoresis 总被引：30，自引：0，他引：30
An immunoelectroosmophoretic technique for rapid detection of the antigen (SH) associated with the serum hepatitis virus has been devised. The technique maintains the specificity characteristic of the Ouchterlony gel-diffusion method, yet detects in 1 to 2 hours one-tenth the amount of antigen required for gel diffusion. The test has immediate application to blood-banking practice since it permits the screening of such labile products as platelets and fresh whole blood, and the detection of antigen in additional serums negative by the Ouchterlony technique. 相似文献
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We studied the effects of anthropogenic edges on predation and parasitism of forest bird nests in an agriculturally fragmented
landscape and a continuously forested landscape in Ontario, Canada. Nesting data were collected at 1937 nests across 10 species
in the fragmented landscape from 2002–2008, and 464 nests across 4 species in the continuously forested landscape from 2006–2008.
Brood parasitism only occurred in the fragmented landscape, and was positively related to the proportion of rural grassland
and row crop habitats within 500-m of nests. Daily nest survival was negatively related to the density of roads within 500-m
of nests in the fragmented landscape, but was not influenced by distance to anthropogenic edge in either landscape. Predation
rates were higher in the fragmented landscape for Ovenbird and Rose-breasted Grosbeak nests, but did not differ between landscapes
for Veery and American Redstart nests. Uniformly high predation in the fragmented landscape may be a result of (1) matrix
predators that penetrate deep (>300 m) into the forest interior, or (2) the additive effect of forest-dependent and matrix-associated
predators that results in high predation pressure in both edge and interior habitats. Further research focused on the identification
of nest predators, their population dynamics, and habitat use is required to understand the underlying mechanisms leading
to uniformly high nest predation in fragmented landscapes. 相似文献