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排序方式: 共有387条查询结果,搜索用时 9 毫秒
41.
O Falusi AL French EC Seaberg PC Tien DH Watts H Minkoff E Piessens A Kovacs K Anastos MH Cohen 《Clinical infectious diseases》2002,35(11):1414-1417
We assessed the prevalence and predictors of latent Toxoplasma infection in a large group of human immunodeficiency virus (HIV)-infected and HIV-uninfected at-risk US women. The prevalence of latent Toxoplasma infection was 15% (380 of 2525 persons) and did not differ by HIV infection status. HIV-infected women aged > or =50 years and those born outside of the United States were more likely to have latent Toxoplasma infection, with prevalences of 32% and 41%, respectively. 相似文献
42.
Kandimalla R van Tilborg AA Kompier LC Stumpel DJ Stam RW Bangma CH Zwarthoff EC 《European urology》2012,61(6):1245-1256
Background
DNA methylation markers could serve as useful biomarkers, both as markers for progression and for urine-based diagnostic assays.Objective
Identify bladder cancer (BCa)–specific methylated DNA sequences for predicting pTa-specific progression and detecting BCa in voided urine.Design, setting, and participants
Genome-wide methylation analysis was performed on 44 bladder tumours using the Agilent 244K Human CpG Island Microarray (Agilent Technologies, Santa Clara, CA, USA). Validation was done using a custom Illumina 384-plex assay (Illumina, San Diego, CA, USA) in a retrospective group of 77 independent tumours. Markers for progression were identified in pTa (n = 24) tumours and validated retrospectively in an independent series of 41 pTa tumours by the SNaPshot method (Applied Biosystems, Foster City, CA, USA).Measurements
The percentage of methylation in tumour and urine samples was used to identify markers for detection and related to the end point of progression to muscle-invasive disease with Kaplan-Meier models and multivariate analysis.Results and limitations
In the validation set, methylation of the T-box 2 (TBX2), T-box 3 (TBX3), GATA binding protein 2 (GATA2), and Zic family member 4 (ZIC4) genes was associated with progression to muscle-invasive disease in pTa tumours (p = 0.003). Methylation of TBX2 alone showed a sensitivity of 100%, a specificity of 80%, a positive predictive value of 78%, and a negative predictive value of 100%, with an area under the curve of 0.96 (p < 0.0001) for predicting progression. Multivariate analysis showed that methylation of TBX3 and GATA2 are independent predictors of progression when compared to clinicopathologic variables (p = 0.04 and p = 0.03, respectively). The predictive accuracy improved by 23% by adding methylation of TBX2, TBX3, and GATA2 to the European Organisation for Research and Treatment of Cancer risk scores. We further identified and validated 110 CpG islands (CGIs) that are differentially methylated between tumour cells and control urine. The limitation of this study is the small number of patients analysed for testing and validating the prognostic markers.Conclusions
We have identified four methylation markers that predict progression in pTa tumours, thereby allowing stratification of patients for personalised follow-up. In addition, we identified CGIs that will enable detection of bladder tumours in voided urine. 相似文献43.
Christian Hafner Arndt Hartmann Johanna M M van Oers Robert Stoehr Ellen C Zwarthoff Ferdinand Hofstaedter Michael Landthaler Thomas Vogt 《Modern pathology》2007,20(8):895-903
Somatic activating fibroblast growth factor 3 (FGFR3) mutations in human skin can cause seborrheic keratoses, one of the most frequent skin tumors in man. However, details of the involved mechanisms remain elusive. We analyzed 65 acanthotic seborrheic keratoses with varying vertical diameters for FGFR3 mutations using a SNaPshot multiplex assay. Immunohistochemistry was performed for Ki-67, bcl-2 and FGFR3 protein in all seborrheic keratoses and 19 normal skin samples. FGFR3 mutations were detected in 37 of 65 seborrheic keratoses (57%). These mutations were found both in flat (initial) and thick seborrheic keratoses. FGFR3 mutations were significantly associated with increased age and localization on the head and neck (P<0.01). Ki-67 expression was significantly higher in seborrheic keratoses than in normal epidermis independent of the FGFR3 status (P<0.001). Furthermore, FGFR3 mutations were associated with an increased expression of bcl-2 and FGFR3 protein (P<0.05). Our results indicate that FGFR3 mutations can occur early in the pathogenesis of at least a subset of seborrheic keratoses. Increased age appears to be a risk factor for these mutations. The preferential occurrence of FGFR3 mutations in seborrheic keratoses of the head and neck suggests a causative role for cumulative lifetime ultraviolet light exposure. 相似文献
44.
Percutaneous transjejunal approaches to the biliary system 总被引:2,自引:0,他引:2
45.
De Klein A; Riegman PH; Bijlsma EK; Heldoorn A; Muijtjens M; den Bakker MA; Avezaat CJ; Zwarthoff EC 《Human molecular genetics》1998,7(3):393-398
We describe a G-->A transition within intron 5 of the NF2 gene. This
mutation creates a consensus splice branch point sequence. To our knowledge
this is the first report of a mutation that creates a functional branch
point sequence in a human hereditary disorder. The new branch point
sequence is located 18 bp upstream of a consensus splice acceptor site. A
consensus splice donor site is found 106 bp 3' of the acceptor site. Asa
consequence the G-->A transition results in an alternatively spliced
mRNA containing an additional exon 5a of 106 bp derived from intron
sequences. We cloned the mutant cDNA and show that due to an in-frame stop
codon the cDNA codes for a truncated NF2 protein. The mutation was observed
in three affected members of an NF2 family. In a tumour of one of the
family members both alternatively spliced and wild-type mRNA were found,
although the wild-type allele of the gene is absent due to an interstitial
deletion on chromosome 22. We also show that immunoprecipitations reveal
the presence of full-length wild-type NF2 protein in the tumour lysate.
These data support the hypothesis that some degree of normal splicing of
the mutant precursor RNA is taking place. It is therefore likely that this
residual activity of the mutant allele explains the relatively mild
phenotype in the family. These data also indicate that complete
inactivation of the gene is not required for tumour formation.
相似文献
46.
Thurman EC; Walker J; Jayaraman S; Manjunath N; Ardman B; Green JM 《International immunology》1998,10(5):691-701
Accessory molecule interactions can be critical in determining the outcome
of a T cell's encounter with antigen. Cell adhesion proteins may augment T
cell responses by facilitating TCR engagement of the antigen-MHC complex,
while co-stimulatory molecules may deliver distinct signals that modulate T
cell responsiveness. CD43 (leukosialin, sialophorin) has been suggested to
influence cell activation by steric hindrance based upon the large size and
glycosylation of the protein, as well as the relative abundance of the
protein on the cell surface. In this paper we examine both in vitro and in
vivo T cell-dependent responses in CD43-deficient mice. We demonstrate that
T cells from CD43-deficient mice are hyper-responsive following both in
vivo and in vitro activation, and that this is observed in response to not
only TCR-CD3-mediated stimulation, but also following receptor-independent
activation. This data suggests that mechanisms other than non-specific
steric hindrance are important in the regulation of T cell activation by
CD43.
相似文献
47.
48.
Emergency room radiography of asthma: an efficacy study 总被引:2,自引:0,他引:2
49.
50.
Two cases of left atrial myxoma were evaluated with magnetic resonance (MR) imaging. In both cases, the myxoma was clearly defined as to its location, origin, and size. In one case, the myxoma prolapsed through the mitral valve. Our study indicates that MR imaging is valuable in the diagnosis of myxomas. 相似文献