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81.
Femke HM Prince Vivian P Bykerk Nancy A Shadick Bing Lu Jing Cui Michelle Frits Christine K Iannaccone Michael E Weinblatt Daniel H Solomon 《Arthritis research & therapy》2012,14(2):R68-8
Introduction
Remission is an important goal of therapy in rheumatoid arthritis (RA), but data on duration of remission are lacking. Our objective was to describe the duration of remission in RA, assessed by different criteria.Methods
We evaluated patients from the Brigham and Women''s Rheumatoid Arthritis Sequential Study (BRASS) not in remission at baseline with at least 2 years of follow-up. Remission was assessed according to the Disease Activity Score 28-C-reactive protein (DAS28-CRP4), Simplified Disease Activity Index (SDAI), and Clinical Disease Activity Index (CDAI) scores, and the recently proposed American College of Rheumatology (ACR)/European League against Rheumatism (EULAR) criteria for remission. Analyses were performed by using Kaplan-Meier survival curves.Results
We identified 871 subjects with ≥2 years of follow-up. Of these subjects, 394 were in remission at one or more time-points and not in remission at baseline, according to at least one of the following criteria: DAS28-CRP < 2.6 (n = 309), DAS28-CRP < 2.3 (n = 275), SDAI (n = 168), CDAI (n = 170), and 2010 ACR/EULAR (n = 158). The median age for the 394 subjects at entrance to BRASS was 56 years; median disease duration was 8 years; 81% were female patients; and 72% were seropositive. Survival analysis performed separately for each remission criterion demonstrated that < 50% of subjects remained in remission 1 year later. Median remission survival time was 1 year. Kaplan-Meier curves of the various remission criteria did not significantly differ (P = 0.29 according to the log-rank test).Conclusions
This study shows that in clinical practice, a minority of RA patients are in sustained remission. 相似文献82.
Background
DNA methylation plays an important role in the process of tumorigenesis. Identifying differentially methylated genes or CpG islands (CGIs) associated with genes between two tumor subtypes is thus an important biological question. The methylation status of all CGIs in the whole genome can be assayed with differential methylation hybridization (DMH) microarrays. However, patient samples or cell lines are heterogeneous, so their methylation pattern may be very different. In addition, neighboring probes at each CGI are correlated. How these factors affect the analysis of DMH data is unknown. 相似文献83.
Fabio Rezzonico Theo HM Smits Emilio Montesinos Jürg E Frey Brion Duffy 《BMC microbiology》2009,9(1):204
Background
Pantoea agglomeransstrains are among the most promising biocontrol agents for a variety of bacterial and fungal plant diseases, particularly fire blight of apple and pear. However, commercial registration ofP. agglomeransbiocontrol products is hampered because this species is currently listed as a biosafety level 2 (BL2) organism due to clinical reports as an opportunistic human pathogen. This study compares plant-origin and clinical strains in a search for discriminating genotypic/phenotypic markers using multi-locus phylogenetic analysis and fluorescent amplified fragment length polymorphisms (fAFLP) fingerprinting. 相似文献84.
Historical biogeography and the evolution of the latitudinal gradient of species richness in the Papionini (Primata: Cercopithecidae) 总被引:1,自引:0,他引:1
MONIKA BÖHM PETER J. MAYHEW 《Biological journal of the Linnean Society. Linnean Society of London》2005,85(2):235-246
We apply historical biogeography techniques to the macaques, baboons and their relatives (Primata: Papionini) and relate the inferred history of range shifts, and associated evolutionary events, to the latitudinal distribution of extant species, which is strongly tropical. The results of reversible parsimony, weighted ancestral area and dispersal-vicariance analyses all agree that Central Africa was part of the range of the ancestor of the tribe. Tropical regions with high current species richness (Central Africa, South-east Asia, Indonesia) have: (1) had a relatively long history of occupation, (2) experienced both a greater number and a greater average rate of speciation events and (3) given rise to more dispersal events to other regions. However, nested sister-taxon comparisons across the tribe show no overall association between differences in latitude and differences in rates of cladogenesis. Our historical reconstructions are largely consistent with previous hypotheses and fossil data, and suggest that both the passage of time since colonization and rates of cladogenesis have enhanced tropical species richness. Historical biogeography may thus considerably aid understanding of this and other spatial problems in macroecology. © 2005 The Linnean Society of London, Biological Journal of the Linnean Society , 2005, 85 , 235–246. 相似文献
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We examined the possible effects of elemental mercury vapor on the liver of the female rats. We divided the animals into an untreated control group and an experimental group that was exposed to mercury vapor for 45 days. Liver samples were obtained for histological and stereological analysis. The total liver, parenchyma and sinusoid volumes were increased significantly in the mercury vapor treated group compared to controls. Also, the mean density, total number and mean nuclear diameter of hepatocytes, except for binucleated hepatocytes, was decreased in the experimental group compared to controls. Light and electron microscopy revealed alterations of liver structure of the experimental animals compared to controls. 相似文献
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BICUCULLINE has been shown to have an action essentially similar to Picrotoxin in antagonizing both synaptically evoked postsynaptic inhibition and the depressant action of γ-amino-butyric acid (GABA) on cuneate neurones1. This supports the hypothesis that GABA is the postsynaptic inhibitory transmitter in the cuneate2. However, evidence3 indicates that GABA has a dual action in the cuneate, not only depressing the excitability of postsynaptic neurones, but also increasing the excitability of primary afferent terminals in a manner which might be expected of a presynaptic inhibitory transmitter. The experiments reported here show that the alkaloids bicuculline and picrotoxin block presynaptic inhibition and that this action is consistent with them exerting a GABA-antagonist action at primary afferent terminals. 相似文献
90.