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Clinical features and treatment outcome of 31 patients over 16 years of age with t(8;21) acute myeloid leukemia (AML) were compared with 60 patients without t(8;21). Among 31 patients with t(8;21), 15 patients were classified as AML-M2 and 11 and 5 patients as AML-M4 and M1, respectively. Of these patients, 28 patients (90.3%) achieved complete remission and 22 patients received consolidative treatment: intermediate-dose cytarabine (IDAC) 11, high-dose cytarabine (HDAC) 6, and allogeneic bone marrow transplantation (BMT) 5. When compared with patients without t(8;21), we could not demonstrate better treatment outcome for t(8;21) AML [median event-free survival (EFS) and overall survival (OS) 10.3 and 12.5 months in AML with t(8;21) vs 11.5 and 15.6 months in AML without t(8;21)]. In the t(8;21) AML group, patients who received HDAC consolidation did not show superior treatment outcome to those who received other consolidative treatment [median EFS: IDAC 11.9 months vs HDAC 9.2 months vs allogeneic BMT 38.1 months (P=NS) and median OS: IDAC 17.8 months vs HDAC 12.0 months vs allogeneic BMT 47.3 months (P=NS)]. Similar treatment outcome between patients with and without t(8;21) and non-superior treatment outcome of HDAC consolidative chemotherapy in the t(8;21) AML group in our study is contradictory to previous reports.These two authors equally contributed to this study: K.-W. Lee and I. S. ChoiSupported by a grant CRI-01-07 from the Cancer Research Institute, Seoul National University College of Medicine, and a grant 05-2001-002 from the S.N.U.H. Research Fund  相似文献   
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Objective

The rhizome of the Cimicifuga racemosa plant (commonly known as black cohosh) has been used for menopausal complaints. Studies regarding the cardiovascular effects of black cohosh are lacking. We investigated the effect of black cohosh on the plasminogen activator system in cultured vascular smooth muscle cells (VSMCs).

Methods

VSMCs were isolated from rat aortae. Expression of plasminogen activator inhibitor type 1 (PAI-1) and tissue-type plasminogen activator (t-PA) proteins were evaluated by Western blot analysis and enzyme-linked immunosorbent assay, respectively. The activities of PAI-1 and t-PA in the conditioned media were assessed by fibrin overlay zymography. A 40% 2-propanol extract of black cohosh was used.

Results

Black cohosh extract (BcEx) stimulated the protein expression of PAI-1, but it did not affect that of t-PA. Vitamin E, a potent antioxidant, inhibited the BcEx-induced increase in PAI-1 expression, while ICI 182,780, an estrogen receptor antagonist, had no effect. Fibrin overlay zymography revealed that BcEx increased the activity of PAI-1 in the conditioned media, while concurrently decreasing that of free t-PA by inducing a binding to PAI-1.

Conclusions

BcEx induces PAI-1 protein expression in the VSMCs likely via an oxidant mechanism. It also stimulates the enzyme activity of PAI-1 and reduces that of free t-PA. These findings suggest that black cohosh might exert a negative influence on fibrinolysis.  相似文献   
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The vast majority of the mouse and human genomes consist of repetitive elements (REs), while protein-coding sequences occupy only ~3 %. It has been reported that the Y chromosomes of both species are highly populated with REs although at present, their complete sequences are not available in any public database. The recent update of the mouse genome database (Build 38.1) from the National Center for Biotechnology Information (NCBI) indicates that mouse chromosome Y is ~92 Mb in size, which is substantially larger than the ~16 Mb reported previously (Build 37.2). In this study, we examined how REs are arranged in mouse chromosome Y (Build 38.1) using REMiner-II, a RE mining program. A combination of diverse REs and RE arrays formed large clusters (up to ~28 Mb in size) and most of them were directly or inversely related. Interestingly, the RE population of human chromosome Y (NCBI Build 37.2-current) was less dense, and the RE/RE array clusters were not evident in comparison to mouse chromosome Y. The annotated gene loci were distributed in five different regions and most of them were surrounded by unique RE arrays. In particular, tandem RE arrays were embedded into the introns of two adjacent gene loci. The findings from this study indicate that the large and interrelated clusters of REs and RE arrays predominantly represent the unique organizational pattern of mouse chromosome Y. The potential interactions among the clusters, which are populated with various interrelated REs and RE arrays, may play a role in the structural configuration and function of mouse chromosome Y.  相似文献   
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IntroductionDissection of regional lymph nodes (RLNs) can lead to significant morbidity and a high prevalence of complications. Published guidance states that these procedures should be carried out by surgeons who are members of a specialist skin multidisciplinary team who carry out a combined minimum of 15 axillary/groin dissections per year. However, there is little evidence to guide this minimum figure of procedures. We report on the burden of service provision and prevalence of complications across the South West of England and Wales.MethodsA 12-month review of dissections of RLNs for skin cancer was undertaken covering five Plastic Surgery Units with a collective catchment of 8.4 million people. Detailed data were collected on patient demographics, pathology, timing of surgery, and prevalence of complications.ResultsA total of 163 dissections were carried out. Forty-three per cent of patients experienced one or more complication. In that 12-month period, an average of 8 axillary/groin dissections was carried out per surgeon. A funnel plot demonstrated that the prevalence of complications for individual surgeons was within the limit of the plot but, in many cases, this was based only on a relatively small number of procedures per consultant. If surgeons carried out 10 procedures per year, the upper and lower limits on the plot were 73% and 11%, respectively.ConclusionsFunnel plots can provide a useful guide as to whether the prevalence of complications for procedures for individual surgeons lies within acceptable limits. Based on these results, 10 procedures per consultant per year should be sufficient to enable meaningful assessment of the prevalence of complications.  相似文献   
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