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排序方式: 共有352条查询结果,搜索用时 750 毫秒
71.
72.
Laursen SB Møllgård K Olesen C Oliveri RS Brøchner CB Byskov AG Andersen AN Høyer PE Tommerup N Yding Andersen C 《Reproductive biomedicine online》2007,15(1):89-98
Characterization of human embryonic stem cell (hESC) lines derived from the inner cell masses of blastocysts generally includes expression analysis of markers such as OCT4, NANOG, SSEA3, SSEA4, TRA-1-60 and TRA-1-81. Expression is usually detected by immunocytochemical staining of entire colonies of hESC, using one colony for each individual marker. Four newly established hESC lines showed the expected expression pattern and were capable of differentiating into the three germ layers in vitro. Neighbouring sections of entire colonies grown for 4, 11, 21 and 28 days respectively were stained with different markers to study the regional distribution and cellular co-expression. TRA-1-60 staining defined the hESC territory at all time points analysed. This territory comprised a characteristic OCT4 and NANOG staining often in overlapping subregions. Staining intensity of nuclei varied from strong OCT4 staining to weak or absent NANOG staining, and vice versa. SSEA4 staining was only observed in small clusters or single cells and not confined to the TRA territory. Co-expression of all markers was only detected in small areas. SSEA1 expression was found exclusively outside the TRA territory. In conclusion, pronounced regional differences in the expression of markers considered specific for undifferentiated hESC may suggest the existence of different cell populations. 相似文献
73.
Grete
stergaard Henrik R. Lam Ole Ladefoged Peter Arlien-Sborg 《Basic & clinical pharmacology & toxicology》1993,72(1):34-39
Abstract: In two separate experiments in rats the irreversible effects of six months'exposure to white spirit (0, 400 p.p.m., and 800 p,p.m.) were studied. In one experiment the exposure started at the age of three months, in the other the rats were 15 months at the beginning of the exposure. After an exposure-free period of several months neurobehavioural, pathological, and neurochemical examinations were performed. A marked difference in motor activity between young and aged animals was found. A slight effect on kidney function was seen at 800 p.p.m. No macroscopic or histopathological changes related to dosing were found. The concentrations of noradrenaline, dopamine, and 5-hydroxytryptamine in various brain regions and in whole brain were irreversibly changed. In conclusion, the study revealed different changes within the CNS, but failed to demonstrate neurobehavioural white spirit-induced neurotoxicity. 相似文献
74.
Elaine Hallisey Eric Tai Andrew Berens Grete Wilt Lucy Peipins Brian Lewis Shannon Graham Barry Flanagan Natasha Buchanan Lunsford 《International journal of health geographics》2017,16(1):29
Background
Transforming spatial data from one scale to another is a challenge in geographic analysis. As part of a larger, primary study to determine a possible association between travel barriers to pediatric cancer facilities and adolescent cancer mortality across the United States, we examined methods to estimate mortality within zones at varying distances from these facilities: (1) geographic centroid assignment, (2) population-weighted centroid assignment, (3) simple areal weighting, (4) combined population and areal weighting, and (5) geostatistical areal interpolation. For the primary study, we used county mortality counts from the National Center for Health Statistics (NCHS) and population data by census tract for the United States to estimate zone mortality. In this paper, to evaluate the five mortality estimation methods, we employed address-level mortality data from the state of Georgia in conjunction with census data. Our objective here is to identify the simplest method that returns accurate mortality estimates.Results
The distribution of Georgia county adolescent cancer mortality counts mirrors the Poisson distribution of the NCHS counts for the U.S. Likewise, zone value patterns, along with the error measures of hierarchy and fit, are similar for the state and the nation. Therefore, Georgia data are suitable for methods testing. The mean absolute value arithmetic differences between the observed counts for Georgia and the five methods were 5.50, 5.00, 4.17, 2.74, and 3.43, respectively. Comparing the methods through paired t-tests of absolute value arithmetic differences showed no statistical difference among the methods. However, we found a strong positive correlation (r = 0.63) between estimated Georgia mortality rates and combined weighting rates at zone level. Most importantly, Bland–Altman plots indicated acceptable agreement between paired arithmetic differences of Georgia rates and combined population and areal weighting rates.Conclusions
This research contributes to the literature on areal interpolation, demonstrating that combined population and areal weighting, compared to other tested methods, returns the most accurate estimates of mortality in transforming small counts by county to aggregated counts for large, non-standard study zones. This conceptually simple cartographic method should be of interest to public health practitioners and researchers limited to analysis of data for relatively large enumeration units.75.
Einar Stensvold Tor ge Myklebust Johan Cappelen Bernt J. Due‐Tnnessen Paulina Due‐Tnnessen Aleksandra Kepka Tom Brge Johannesen Brd Krossnes Tryggve Lundar Snezana Maric Hrvoje Miletic Viggo Moholdt Kristin Smistad Myrmel Terje Nordberg Jana Rydland Tore Stokland Kristin Solem Ole Solheim Ingrid Torsvik Gry C. Wikran Bernward Zeller Finn Wesenberg Anne Grete Bechensteen Petter Brandal 《Pediatric blood & cancer》2019,66(10)
76.
Extended spectrum cephalosporin resistance among clinical isolates of Enterobacteriaceae in West Norway during 2006–2013; a prospective surveillance study
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Haima Mylvaganam Helge Kolstad Rebecca Irene Breistein Grete Lind Dag Harald Skutlaberg 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2017,125(1):52-58
Routine surveillance of resistance to broad‐spectrum cephalosporins in Enterobacteriaceae and phenotypic identification of underlying mechanisms using a simple strategy was commenced in 2006 at our laboratory, serving West Norway. This report focuses on the results until 2013. The classical plasmid‐mediated extended spectrum beta‐lactamase (ESBLA) among clinically relevant Escherichia coli isolates showed an increase from 0.6% to 4.3% during the surveillance period, while prevalence for other mechanisms remained stable, below 0.7%. ESBLA in Klebsiella pneumoniae had similar prevalence in 2006 (0.6%) and 2013 (4.4%), but in between it peaked to 3.9% in 2008 and to 9.3% in 2011. Within the other species, the numbers of clinically relevant isolates and isolates‐producing ESBLA were much lower. An increasing resistance due to hyperproduction of AmpC enzymes was seen in Enterobacter and Citrobacter, with prevalence increasing from 18% and 12.2% in 2006 to 27.5% and 26.1% in 2013, respectively. Hyperproduction of KOXY enzyme in Klebsiella oxytoca remained below 9.5% and did not show an increasing trend. The overall increase in the proportions of isolates‐producing ESBLA in E. coli/K. pneumoniae and hyperproduction of AmpC in Enterobacter/Citrobacter necessitates measures to hinder the spread of resistant bacteria and vigilant antibiotic stewardship. 相似文献
77.
78.
Definition of MHC and T cell receptor contacts in the HLA-DR4restricted immunodominant epitope in type II collagen and characterization of collagen-induced arthritis in HLA-DR4 and human CD4 transgenic mice 总被引:6,自引:0,他引:6
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Ellen Christina Andersson Bjarke Endel Hansen Helle Jacobsen Lars S. Madsen Claus B. Andersen Jan Engberg Jonathan B. Rothbard Grete Snderstrup McDevitt Vivianne Malmstrm Rikard Holmdahl Arne Svejgaard Lars Fugger 《Proceedings of the National Academy of Sciences of the United States of America》1998,95(13):7574-7579
Rheumatoid arthritis (RA) is an autoimmune disease associated with the HLA-DR4 and DR1 alleles. The target autoantigen(s) in RA is unknown, but type II collagen (CII) is a candidate, and the DR4- and DR1-restricted immunodominant T cell epitope in this protein corresponds to amino acids 261–273 (CII 261–273). We have defined MHC and T cell receptor contacts in CII 261–273 and provide strong evidence that this peptide corresponds to the peptide binding specificity previously found for RA-associated DR molecules. Moreover, we demonstrate that HLA-DR4 and human CD4 transgenic mice homozygous for the I-Abβ0 mutation are highly susceptible to collagen-induced arthritis and describe the clinical course and histopathological changes in the affected joints. 相似文献
79.
Effect of animal‐assisted interventions on depression,agitation and quality of life in nursing home residents suffering from cognitive impairment or dementia: a cluster randomized controlled trial
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80.