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51.
Kuiken T Rimmelzwaan G van Riel D van Amerongen G Baars M Fouchier R Osterhaus A 《Science (New York, N.Y.)》2004,306(5694):241
During the 2003 to 2004 outbreak of avian influenza A (H5N1) virus in Asia, there were anecdotal reports of fatal infection in domestic cats, although this species is considered resistant to influenza. We experimentally inoculated cats with H5N1 virus intratracheally and by feeding them virus-infected chickens. The cats excreted virus, developed severe diffuse alveolar damage, and transmitted virus to sentinel cats. These results show that domestic cats are at risk of disease or death from H5N1 virus, can be infected by horizontal transmission, and may play a role in the epidemiology of this virus. 相似文献
52.
Zhou D Cantu C Sagiv Y Schrantz N Kulkarni AB Qi X Mahuran DJ Morales CR Grabowski GA Benlagha K Savage P Bendelac A Teyton L 《Science (New York, N.Y.)》2004,303(5657):523-527
It is now established that CD1 molecules present lipid antigens to T cells, although it is not clear how the exchange of lipids between membrane compartments and the CD1 binding groove is assisted. We report that mice deficient in prosaposin, the precursor to a family of endosomal lipid transfer proteins (LTP), exhibit specific defects in CD1d-mediated antigen presentation and lack Valpha14 NKT cells. In vitro, saposins extracted monomeric lipids from membranes and from CD1, thereby promoting the loading as well as the editing of lipids on CD1. Transient complexes between CD1, lipid, and LTP suggested a "tug-of-war" model in which lipid exchange between CD1 and LTP is on the basis of their respective affinities for lipids. LTPs constitute a previously unknown link between lipid metabolism and immunity and are likely to exert a profound influence on the repertoire of self, tumor, and microbial lipid antigens. 相似文献
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Fernandez-Gonzalez A La Spada AR Treadaway J Higdon JC Harris BS Sidman RL Morgan JI Zuo J 《Science (New York, N.Y.)》2002,295(5561):1904-1906
The classical recessive mouse mutant, Purkinje cell degeneration (pcd), exhibits adult-onset degeneration of cerebellar Purkinje neurons, retinal photoreceptors, olfactory bulb mitral neurons, and selected thalamic neurons, and has defective spermatogenesis. Here we identify Nna1 as the gene mutated in the original pcd and two additional pcd alleles (pcd2J and pcd3J). Nna1 encodes a putative nuclear protein containing a zinc carboxypeptidase domain initially identified by its induction in spinal motor neurons during axonal regeneration. The present study suggests an unexpected molecular link between neuronal degeneration and regeneration, and its results have potential implications for neurodegenerative diseases and male infertility. 相似文献
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He H Liyanarachchi S Akagi K Nagy R Li J Dietrich RC Li W Sebastian N Wen B Xin B Singh J Yan P Alder H Haan E Wieczorek D Albrecht B Puffenberger E Wang H Westman JA Padgett RA Symer DE de la Chapelle A 《Science (New York, N.Y.)》2011,332(6026):238-240
Small nuclear RNAs (snRNAs) are essential factors in messenger RNA splicing. By means of homozygosity mapping and deep sequencing, we show that a gene encoding U4atac snRNA, a component of the minor U12-dependent spliceosome, is mutated in individuals with microcephalic osteodysplastic primordial dwarfism type I (MOPD I), a severe developmental disorder characterized by extreme intrauterine growth retardation and multiple organ abnormalities. Functional assays showed that mutations (30G>A, 51G>A, 55G>A, and 111G>A) associated with MOPD I cause defective U12-dependent splicing. Endogenous U12-dependent but not U2-dependent introns were found to be poorly spliced in MOPD I patient fibroblast cells. The introduction of wild-type U4atac snRNA into MOPD I cells enhanced U12-dependent splicing. These results illustrate the critical role of minor intron splicing in human development. 相似文献
59.
For analysis of drug dosage forms, precision measures of AOAC approved automated methods, usually containing a spectrophotometric or fluorometric measurement step, were recalculated on a consistent statistical basis, using a computer program "FDACHEMIST." Ten collaborative studies of 14 compounds in 38 materials, consisting of various dosage forms, usually in 10 replications by an average of 7 laboratories, with a total of 2461 determinations, were reviewed. The average relative standard deviations within-laboratory (RSDo) and among-laboratories (RSDx) were 1.1 and 1.9%, respectively, and the ratio of RSDo/RSDx was 0.57, with an average outlier rate of 0.57% of the reported values. The line of best fit for RSDx plotted against - log concentration increases slightly with decreasing concentration, extending from an RSDx of about 1.6% at 100% concentration to an RSDx of 2.2% at 0.1% concentration, a change in RSDx of about 0.2% for a 10-fold decrease in concentration, independent of analyte and matrix. 相似文献
60.
Albert C. Trouse 《Soil & Tillage Research》1983,3(1):67-81
A technique of subsoiling directly under the row to be planted has been found to be beneficial, because barriers to root development are pierced in a location that is difficult to recompact. Over a 15-year period, average yields increased substantially in the southeastern United States when this system was practiced. However, the increases were not consistent, and some reasons for those variations are analyzed. 相似文献