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51.
52.
Members of the HRT family of basic helix-loop-helix proteins act as transcriptional repressors downstream of Notch signaling 总被引:3,自引:0,他引:3
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53.
The use of polymorphic DNA and protein markers for the third complement component for determining linkage of familial hypercholesterolaemia 总被引:4,自引:0,他引:4
S E Humphries J A Donald J J McFadden S Shull R Williamson N I Jowett D J Galton J O Julsrud K Berg A Heiberg 《Atherosclerosis》1984,52(3):267-278
We have used DNA and protein polymorphisms for the third complement component (C3) to assess the potential of DNA markers in the diagnosis and study of familial hypercholesterolaemia (FH), and to confirm the reported linkage between FH and C3. The inheritance of FH and the C3 gene has been studied in 10 families by combining information from both the protein and DNA polymorphisms. Our results confirm that the C3 gene is loosely linked to the gene causing FH (lod score maximum of 2.0) at a recombination distance of 0.15. When these results are combined with previously published data the overall lod score maximum is 4.75 at a recombination distance of 0.2, meaning that the two genes will be inherited together in only about 80% of children. These results confirm that the gene that causes familial hypercholesterolaemia is linked to C3 and is therefore on chromosome 19, but C3 is not close enough to be used as a diagnostic marker. 相似文献
54.
Bash RO; Crist WM; Shuster JJ; Link MP; Amylon M; Pullen J; Carroll AJ; Buchanan GR; Smith RG; Baer R 《Blood》1993,81(8):2110-2117
Alteration of the TAL1 locus is the most common nonrandom genetic defect in childhood T-cell acute lymphoblastic leukemia (T-ALL). To determine if rearrangements of the TAL1 proto-oncogene confer a distinct leukemic phenotype, we studied leukemic peripheral blood or bone marrow samples from 182 children with newly diagnosed T-ALL enrolled on Pediatric Oncology Group treatment protocols. Forty-eight (26%) of the samples had a local rearrangement of the TAL1 locus. Demographic and clinical features were compared for patient subgroups with and without TAL1 rearrangements. The only clinical correlates that were significantly associated with TAL1 gene rearrangements were higher white blood cell count (P = .017) and higher hemoglobin (P = .007) at diagnosis. Immunophenotypically, samples with altered TAL1 were more likely to be CD2+ (P = .001) and lack CD10 (cALLa) expression (P = .007) than those without the rearrangement. There was a trend toward improved event-free survival (EFS) in patients with TAL1 rearrangements (4-year EFS was 44% +/- 7% for patients without the rearrangements v 59% +/- 11% for those with rearrangements), but the difference was not significant (P = .34). The role of TAL1 in leukemogenesis has yet to be clearly defined, and the prognostic significance of TAL1 gene rearrangements in T-ALL deserves further study. 相似文献
55.
Marijt WA; Veenhof WF; Goulmy E; Willemze R; van Rood JJ; Falkenburg JH 《Blood》1993,82(12):3778-3785
HLA-identical bone marrow transplantation (BMT) may be complicated by graft-versus-host disease or graft rejection. Both complications are thought to be initiated by recognition of minor histocompatibility (mH) antigens by HLA-restricted mH-antigen-specific T lymphocytes. Using HLA- A2-restricted mH antigens HA-1-, -2-, and -4-, and HY-specific cytotoxic T lymphocyte (CTL) clones, we studied the recognition by these CTL clones of interleukin-2 (IL-2)-stimulated T cells (IL-2 blasts), BM mononuclear cells (BMMNCs), and hematopoietic progenitor cells (HPCs). We showed that, when IL-2 blasts from the BM donors who were investigated were recognized by the HA-1-, -2-, and -4-, and HY- specific CTL clones, their BMMNCs and HPCs were recognized as well by these CTL clones, resulting in antigen-specific growth inhibition of erythrocyte burst-forming units (BFU-E), colony-forming units- granulocyte (CFU-G), and CFU-macrophage (CFU-M). the HA-2-specific CTL clone, however, inhibited BFU-E and CFU-G growth from four donors to a lesser extent than from two other donors. We further investigated whether inhibitory cytokines released into the culture medium by the antigen-specific stimulated CTLs or by stimulated BMMNCs were responsible for suppression of HPC growth or whether this effect was caused by direct cell-cell contact between CTLs and HPCs. HPC growth inhibition was only observed after preincubation of BMMNCs and CTLs together for 4 hours before plating the cells in semisolid HPC culture medium. When no cell-cell contact was permitted before plating, neither antigen-stimulated CTL nor antigen-nonstimulated CTLs provoked HPC growth inhibition. Culturing BMMNCs in the presence of supernatants harvested after incubation of BMMNCs and CTL clones together for 4 or 72 hours did also not result in HPC growth inhibition. Both suppression of HPC growth and lysis of IL-2 blasts and BMMNCs in the 51Cr-release assay appeared to be dependent on direct cell-cell contact between target cells and CTLs and were not caused by the release of inhibitory cytokines into the culture medium by antigen-specific stimulated CTLs or by stimulated BMMNCs. Our results show that mH-antigen-specific CTLs can inhibit HPC growth by a direct cytolytic effect and may therefore be responsible for BM graft rejection after HLA-identical BMT. 相似文献
56.
Lemos PA Arampatzis CA Hoye A Daemen J Ong AT Saia F van der Giessen WJ McFadden EP Sianos G Smits PC de Feyter P Hofma SH van Domburg RT Serruys PW 《The American journal of cardiology》2005,95(2):167-172
Renal impairment is an important predictor of mortality after percutaneous coronary intervention and may increase the restenosis rate. However, the relation between restenosis and the risk of death in patients who have renal impairment remains unclear. We evaluated the incidences of repeat revascularization and mortality in patients who had renal impairment and those who did not and who received sirolimus-eluting stents or bare stents. A total of 1,080 consecutive patients treated for 1 year had available data to calculate baseline creatinine clearance. Patients received bare stents (first 6 months, n = 543) or sirolimus-eluting stents (last 6 months, n = 537) and were grouped according to the presence or absence of renal impairment (creatinine clearance <60 ml/min). Patients who had renal impairment had a higher mortality rate at 1 year (7.6% vs 2.5%, hazard ratio 3.14, 95% confidence interval 1.68 to 5.88, p <0.01), with no differences in mortality between patients who received bare stents and those who received sirolimus-eluting stents (hazard ratio 0.91, 95% confidence interval 0.49 to 1.68, p = 0.8). The incidence of target vessel revascularization decreased significantly in patients who were treated with sirolimus-eluting stents and did not have renal impairment (hazard ratio 0.59, 95% confidence interval 0.39 to 0.90, p = 0.01) and in those who had decreased renal function (hazard ratio 0.37, 95% confidence interval 0.15 to 0.90, p = 0.03). Thus, sirolimus-eluting stents compared with conventional stents decreased clinical restenosis in patients who had renal impairment. However, this benefit was not paralleled by a decrease in the risk of death in this population. It seems unlikely that restenosis could be a contributing factor that influenced the increased mortality of patients who had impaired renal function. 相似文献
57.
Corzo D; Yunis JJ; Salazar M; Lieberman JA; Howard A; Awdeh Z; Alper CA; Yunis EJ 《Blood》1995,86(10):3835-3840
Genes of the major histocompatibility complex (MHC) have been associated with susceptibility to drug-induced adverse reactions. We previously found that clozapine-induced agranulocytosis (CA) is associated with the HLA-DRB1*0402, DRB4*0101, DQB1*0302, DQA1*0301 haplotype in Ashkenazi Jewish patients and with the HLA-DRB1*1601, DRB5*02, DQB1*0502, DQA1*0102 haplotype in non-Jewish patients. In the present study, we tested the hypothesis that the variants of the heat- shock protein 70 (HSP-70) encoded by the HSP-70 loci located within the MHC region and known to be involved in apoptosis and regulation of cell proliferation could play an important role in molecular mechanisms of CA. First, we analyzed HSP70-2 polymorphism in risk-associated haplotypes from HLA homozygous cells and normal individuals and confirmed that the HSP70-2 9-kb variant was associated invariably with DR4 (HLA-DRB1*0402, DQB1*0302) and DR2 (HLA-DRB1*01601, DQB1*0502, DQA1*0102 and HLA-DRB1*1501, DQB1*0602) haplotypes, which were the haplotypes found increased in Jewish and non-Jewish patients with CA, respectively. The 9.0-kb variant was also found to be associated with HLA-B44, DRB1*0401 and HLA-B44, DRB1*07 haplotypes. Second, in patients with CA (12 Ashkenazi Jewish and 20 non-Jewish patients), HSP70-1 A and HSP70-2 9.0-kb variants were associated with the MHC haplotypes found by us to be markers of susceptibility to CA. The clozapine-treated control group had an excess number of HSP70-1 C and HSP70-2 8.5-kb variants, consistent with genetic resistance to CA associated with those variants. This finding supports our hypothesis that a dominant gene within the MHC region (marked by HSP70-1 and HSP70-2), but not necessarily HLA, is associated with CA in two different ethnic groups. 相似文献
58.
The purpose of this paper is to report the longitudinal effects of the ‘Teaching Kids to Cope with Anger’ (TKC-A) program on self-reported anger in rural youth. Through a randomized controlled trial, 179 youths of 14–18 years of age, from three rural high schools, were randomized into a control (n = 86) and an intervention group (n = 93) for eight TKC-A weekly sessions. These students completed the STAXI-2 anger instrument questionnaires at baseline, post-intervention, 6 months, and at 1 year. T-test statistics were used to analyze and compare the control and intervention groups. Through analysis of the Anger Index sub-scale of the STAXI-2 at 1 year post-intervention, a significant difference was reported between the control and intervention group. Participants reported that the TKC-A intervention was helpful in coping with emotional, behavioral, and social aspects of anger. Future research may utilize the TKC-A with youth who have anger management problems. Psychiatric-mental health nurses can screen youth for anger and be cognizant of coping skills of youth, assess for anger problems and provide health education to youth about approaches for coping with anger. 相似文献
59.
Lindsay A Bliss Catherine J Yang Zeling Chau Sing Chau Ng David W McFadden Tara S Kent A James Moser Mark P Callery Jennifer F Tseng 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2014,16(10):899-906
Background
The volume effect in pancreatic surgery is well established. Regionalization to high-volume centres has been proposed. The effect of this proposal on practice patterns is unknown.Methods
Retrospective review of pancreatectomy patients in the Nationwide Inpatient Sample 2004–2011. Inpatient mortality and complication rates were calculated. Patients were stratified by annual centre pancreatic resection volume (low <5, medium 5–18, high >18). Multivariable regression model evaluated predictors of resection at a high-volume centre.Results
In total, 129 609 patients underwent a pancreatectomy. The crude inpatient mortality rate was 4.3%. 36.0% experienced complications. 66.5% underwent a resection at high-volume centres. In 2004, low-, medium- and high-volume centres resected 16.3%, 24.5% and 59.2% of patients, compared with 7.6%, 19.3% and 73.1% in 2011. High-volume centres had lower mortality (P < 0.001), fewer complications (P < 0.001) and a shorter median length of stay (P < 0.001). Patients at non-high-volume centres had more comorbidities (P = 0.001), lower rates of private insurance (P < 0.001) and more non-elective admissions (P < 0.001).Discussion
In spite of a shift to high-volume hospitals, a substantial cohort still receives a resection outside of these centres. Patients receiving non-high-volume care demonstrate less favourable comorbidities, insurance and urgency of operation. The implications are twofold: already disadvantaged patients may not benefit from the high-volume effect; and patients predisposed to do well may contribute to observed superior outcomes at high-volume centres. 相似文献60.