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排序方式: 共有526条查询结果,搜索用时 15 毫秒
51.
Pretreatment hematocrit in 117 advanced-stage Hodgkin's disease patients treated with a combined modality therapy program was evaluated as an independent prognostic variable with regard to survival and relapse-free survival. Age greater than 40 years, and multiple extranodal sites of involvement were found to be statistically significant independent negative prognostic factors with regard to survival. Pretreatment hematocrit, however, was not an independent negative prognostic variable. 相似文献
52.
A microculture assay for murine granulocyte-macrophage colony- stimulating factor (GM-CSF) has been developed using fetal liver GM colony-forming cells (CFC) isolated by fluorescence-activated cell sorting. These GM-CFC are free of mature hemopoietic cells, such as granulocytes and macrophages, which may interfere with direct assays for GM-CSF. The assay procedure allows the quantitation of GM-CSF within 48 hr by measuring the number of cells produced from 50 GM-CFC in microcultures (15 microliter). The assay is particularly simple to set up and score and yet, because of the reduced volumes, this assay is still capable of detecting 0.2 pg (i.e., 0.2 U) of GM-CSF within 48 hr, i.e., 100 times less GM-CSF than the conventional soft agar assay. By allowing the microcultures to develop for 7 days, the extra proliferation allows a further tenfold increase in the sensitivity of CSF detection. The time and cost of setting up hundreds of GM-CSF assays for fractions from chromatographic columns, e.g., reverse phase high performance liquid chromatography, is reduced by at least five- fold. Enough GM-CFC can be isolated and stored frozen in one afternoon to provide sufficient cells for the daily assay of 200 samples of GM- CSF for several months. Microassay results for several sources of GM- CSF at different stages of purification are compared to the results obtained from the soft agar assay. 相似文献
53.
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
54.
Ö. Başar M.D. E. Akbal S. Köklü Y. Tuna E. Koçak N. Başar D. Tok H. Erbiş M. Şenes 《Herz》2013,38(4):417-422
Aim
Nonalcoholic fatty liver disease (NAFLD) is the most common liver disorder which is reported as the hepatic manifestation of metabolic syndrome with an increased risk of cardiovascular events. Patients with NAFLD are also at risk of future cardiac events independently of metabolic syndrome. The aim of this study was to examine serum concentrations of heart type fatty acid binding protein (H-FABP) in NAFLD and to investigate its correlations with metabolic parameters and subclinical atherosclerosis.Patients and methods
A total of 34 patients with NAFLD and 35 healthy subjects were enrolled in the study. NAFLD patients had elevated liver enzymes and steatosis graded on ultrasonography. Healthy subjects had normal liver enzymes and no steatosis on ultrasonography. H-FABP levels were measured using an enzyme linked immunosorbent assay (ELISA) method and correlations with metabolic parameters and subclinical atherosclerosis were examined. Subclinical atherosclerosis was determined with carotid artery intima–media thickness (CIMT) which was measured by high resolution B mode ultrasonography.Results
H-FABP levels were elevated in patients with NAFLD (16.3?±?4.0 ng/ml) when compared with healthy controls (13.8?±?2.1 ng/ml; p??<?0.001). NAFLD patients had significantly higher CIMT than the controls had (0.64?±?0.17 mm vs. 0.43?±?0.14 mm, p?=?0.009). The H-FABP concentrations were significantly positively correlated with body mass index (r?=?0.255, p?=?0.042), fasting blood glucose level (r?=?0.300, p?=?0.013), CIMT (r?=?0.335, p?=?0.043), and homeostasis model assessment-estimated insulin resistance (HOMA-IR; r?=?0.156, p?=?0.306). In multiple linear regression analysis, H-FABP levels were only independently associated with CIMT (p?=?0.04)Conclusion
Serum H-FABP concentrations increase in patients with NAFLD. Our results may not only suggest that H-FABP is a marker of subclinical myocardial damage in patients with NAFLD but also of subclinical atherosclerosis, independent of metabolic syndrome and cardiac risk factors. 相似文献55.
56.
Percutaneous transjejunal approaches to the biliary system 总被引:2,自引:0,他引:2
57.
58.
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
59.
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
60.