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991.
Marinescu VD Kohane IS Kim TK Harmin DA Greenberg ME Riva A 《Bioinformatics (Oxford, England)》2006,22(8):999-1001
992.
Haas KM Sen S Sanford IG Miller AS Poe JC Tedder TF 《Journal of immunology (Baltimore, Md. : 1950)》2006,177(5):3063-3073
The CD22 extracellular domain regulates B lymphocyte function by interacting with alpha2,6-linked sialic acid-bearing ligands. To understand how CD22 ligand interactions affect B cell function in vivo, mouse anti-mouse CD22 mAbs were generated that inhibit CD22 ligand binding to varying degrees. Remarkably, mAbs which blocked CD22 ligand binding accelerated mature B cell turnover by 2- to 4-fold in blood, spleen, and lymph nodes. CD22 ligand-blocking mAbs also inhibited the survival of adoptively transferred normal (73-88%) and malignant (90%) B cells in vivo. Moreover, mAbs that bound CD22 ligand binding domains induced significant CD22 internalization, depleted marginal zone B cells (82-99%), and reduced mature recirculating B cell numbers by 75-85%. The CD22 mAb effects were independent of complement and FcRs, and the CD22 mAbs had minimal effects in CD22AA mice that express mutated CD22 that is not capable of ligand binding. These data demonstrate that inhibition of CD22 ligand binding can disrupt normal and malignant B cell survival in vivo and suggest a novel mechanism of action for therapeutics targeting CD22 ligand binding domains. 相似文献
993.
Microplate fluorescence assay for the quantification
of double stranded DNA using SYBR Green I dye 总被引:1,自引:0,他引:1
A high-throughput, 96-well microplate fluorescence assay (MFA) was developed for DNA quantification using the double-stranded DNA-binding dye SYBR Green I. Samples mixed with SYBR Green I in the wells of a microtiter plate produced fluorescence in proportion with DNA concentration which was measured using a fluorescence plate reader. The performance characteristics of the assay were compared with spectrophotometric quantification based on ultraviolet absorption and the Hoefer DyNA Quant assay utilizing the fluorescent dye, Hoechst 33258. The MFA accurately quantified different types of DNA over a broad linear dynamic range of concentrations (0.25–2,500 pg/μl), and was not affected by a variety of contaminants in the assay mixture. 相似文献
994.
By experimenting with many different circularly permutated yellow fluorescent protein (cpYFP) variants as acceptors in fluorescence
resonance energy transfer based biosensors, the optimal dynamic range can be discovered by sampling the possibilities of relative
fluorophore orientations before and after bioactivity. Hence, to facilitate the sampling process, we introduced a new approach
to construct a library of cpYFP variants using fluorescence screening and a tandem fusion template. This new approach is rapid
because it does not require creating intermediate N- and C-terminal fragments and it allows quick screening for positive colonies by fluorescence. As a demonstration, eleven cpYFP
variants were created and eight showed fluorescence. The emission and excitation spectra of these cpYFP variants showed strong
similarity to YFP and therefore can be used in replacement.
Revisions requested 27 October 2005; Revisions received 23 December 2005 相似文献
995.
In this paper, the insectivores, chiropterans and rodents from the middle Miocene site of Can Missert are described. The faunal list of this locality includes the following species: Miosorex grivensis, Desmanella sp., Talpidae indet., Vespertilionidae indet., Hispanomys daamsi, Megacricetodon minor, Megacricetodon ibericus, Fahlbuschia crusafonti, Democricetodon brevis nemoralis, Eumyarion medium, Muscardinus hispanicus, Eomuscardinus sp., Paraglirulus werenfelsi and Spermophilinus bredai. H. daamsi is a new Cricetodontine species which is characterized by complete ectolophs and relatively long third lower molars. The rodent association of Can Missert enable one to assign this locality to the late Aragonian, MN 8, being close in age to other localities in the Vallès-Penedès Basin such as Castell de Barberà. However, the proportion in which each species is represented is very different in the two cases. This evidence points to the existence climatic pulses at the end of the Aragonian Mammal-Stage. 相似文献
996.
Although gene and protein measurements are increasing in quantity and comprehensiveness, they do not characterize a sample's entire phenotype in an environmental or experimental context. Here we comprehensively consider associations between components of phenotype, genotype and environment to identify genes that may govern phenotype and responses to the environment. Context from the annotations of gene expression data sets in the Gene Expression Omnibus is represented using the Unified Medical Language System, a compendium of biomedical vocabularies with nearly 1-million concepts. After showing how data sets can be clustered by annotative concepts, we find a network of relations between phenotypic, disease, environmental and experimental contexts as well as genes with differential expression associated with these concepts. We identify novel genes related to concepts such as aging. Comprehensively identifying genes related to phenotype and environment is a step toward the Human Phenome Project. 相似文献
997.
998.
999.
Elena Alonso Carlos Fernández Isaac Najera Javier Pro José V. Tarazona Gregoria Carbonell 《Soil & Sediment Contamination》2006,15(3):327-337
Multi-species soil systems (MS·3) are homogeneous soil columns that allow a combined assessment of chemical fate and effects on representative soil organisms. Theoretically, the presence of organisms can modify the movement of chemicals in the soil core. This influence was studied for copper and cadmium comparing the results on MS·3 with earthworms and two plant species versus soil columns without organisms. Metals were applied on the top of the soil at three doses: low (3.4 g Cu/ha + 1.7 g Cd/ha), medium (8.5 g Cu/ha + 4.3 g Cd/ha) and high (17 g Cu/ha + 8.5 g Cd/ha). Three organic compounds (pentachlorophenol, 4-chlorophenol and chlorpyrifos) were applied. Toxicity and metal levels in biota followed dose-response relationships. Results showed higher metal concentrations in the depth layers of MS·3 than in the soil columns. The effect was higher for the lower dose, where organisms were less affected, than at the higher doses, where very severe toxicity was observed, confirming the role of organisms in the enhanced mobility. 相似文献
1000.