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941.
942.
目的:探讨抑制半乳糖凝集素3(galectin-3)的表达对人胃癌MGC-803细胞凋亡的影响,为基因靶向治疗提供潜在靶点。方法:人胃癌MGC-803细胞分为siRNA干扰组、空白对照组和阴性对照组,siRNA干扰组MGC-803细胞转染靶向galectin-3的siRNA,空白对照组MGC-803细胞只加转染试剂,阴性对照组MGC-803细胞转染阴性对照的siRNA。采用流式细胞术和碘化丙啶(PI)染色法检测各组细胞凋亡率和细胞凋亡情况,Western blotting法检测各组细胞中galectin-3、Bcl-2和Bax蛋白表达情况。结果:与阴性对照组和空白对照组比较,siRNA干扰组细胞中galectin-3蛋白表达水平明显降低(P<0.05)。PI染色,siRNA干扰组凋亡细胞数量明显增加,凋亡细胞出现细胞核固缩、染色质浓集、新月形和凋亡小体等细胞凋亡特征,阴性对照组仅有少量散在的凋亡细胞。流式细胞术和Western blotting法检测,与阴性对照组和空白对照组比较,siRNA干扰组细胞凋亡率明显升高(P<0.05),Bcl-2蛋白表达水平明显降低(P<0.05),Bax蛋白表达水平未发生明显变化(P>0.05)。结论:抑制galectin-3表达可促进MGC-803细胞的凋亡,提示galectin-3对胃癌细胞发挥癌基因作用,具有成为靶向治疗靶点的可能性。  相似文献   
943.
《中国现代医生》2020,58(29):170-173+177
目的 研究高流量呼吸湿化治疗仪(HFNC)在食管癌术后并发急性呼吸衰竭患者治疗中的临床效果。方法 选取复旦大学附属中山医院2017 年1 月~2018 年6 月45 例食管癌术后并发急性呼吸衰竭的患者作为研究对象,分为观察组和对照组。对照组22 例患者采用传统方法氧疗,观察组23 例患者采用高流量呼吸湿化治疗仪治疗。比较两组患者在睡眠时间、动脉血氧分压、心率、呼吸率、SpO2、气管插管率等在治疗后的上述指标差异。结果 治疗后,与对照组相比,观察组患者睡眠时间延长,动脉血氧分压显著提高,心率趋于平稳,呼吸率下降,SpO2 有明显改善(P<0.05,P<0.001)。治疗后,观察组患者的气管插管率为13.0%(3/23),低于对照组的27.3%(6/22),但差异无统计学意义(P>0.05)。结论 高流量呼吸湿化治疗仪(HFNC)的使用可显著提高食管癌术后并发急性呼吸衰竭患者的氧疗效果、给氧舒适度及睡眠时间,患者易于接受,可以改善患者的呼吸功能。  相似文献   
944.
The estimation of survival of myelodysplastic syndromes (MDS) and risk of progression into acute myeloid leukaemia is challenging due to the heterogeneous clinical course. The most widely used prognostic scoring system (International Prognostic Scoring System [IPSS]) was recently revised (IPSS‐R). The aim of this study was to investigate the prognostic relevance of flow cytometry (FC) in the context of the IPSS‐R. Bone marrow aspirates were analysed by FC in 159 patients with MDS. A flow score was calculated by applying the flow cytometric scoring system (FCSS). Patients were assigned to IPSS and IPSS‐R risk groups. The FCSS correlated with the World Health Organization classification, IPSS and IPSS‐R risk groups. Mild flow cytometric abnormalities were associated with significantly better overall survival (OS) and lower risk of disease evolution. The presence of aberrant myeloid progenitors was associated with transfusion dependency and disease progression. Most importantly, the FCSS identified prognostic subgroups within the IPSS‐R cytogenetic good risk and low risk group. Flow cytometric analysis in patients with MDS provides additional prognostic information and is complementary to the IPSS‐R. The addition of a flow cytometric score next to the clinical parameters within the IPSS‐R is a further refinement of prognostication of patients with MDS.  相似文献   
945.
Percutaneous coronary intervention (PCI) of small coronary vessels represents a real challenge for myocardial revascularization because of the high risk of stent-restenosis and increased risk of adverse clinical events. Moreover, small coronary arteries supply small myocardial territories therefore questioning the clinical significance of small-vessel stenoses. The definition of small-vessel disease and PCI-strategies used are very heterogeneous across studies. The present review will focus on percutaneous coronary revascularization in patients with small vessel coronary artery disease.  相似文献   
946.
Multiparameter flow cytometry (MFC) identifies rare cases of biclonal disease in chronic lymphocytic leukaemia (CLL). By MFC, we identified 76 patients with biclonal disease in a cohort of 5523 CLL patients (1·4%). Fluorescence in situ hybridization and chromosome banding analysis revealed five and six cases, respectively, with two different cytogenetic aberrations due to clonal evolution. Two different B‐cell receptor rearrangements and IGHV subtypes were more frequent in biclonal than in monoclonal CLL by MFC (37·1% vs. 2·7%; < 0·001). Patients with biclonal CLL by MFC showed a trend to a shorter time to treatment than monoclonal CLL (P = 0·080).  相似文献   
947.
Paroxysmal nocturnal haemoglobinuria (PNH) clones are frequently detected in patients with aplastic anaemia (AA). To evaluate the prognostic role of PNH clone presence we conducted a prospective study in 125 AA patients treated with combined immunosuppressive therapy (IST). Seventy‐four patients (59%) had a PNH clone (PNH+ patients) at diagnosis, with a median clone size of 0·60% in granulocytes and 0·15% in red blood cells. The response rate at 6 months was higher in PNH+ patients than that in PNH‐ patients, both after first‐ and second‐line IST: 68% vs. 45%, = 0·0164 and 53% vs. 13%, = 0·0502 respectively. Moreover, 42% of PNH+ patients achieved complete remission compared with only 16% of PNH‐ patients (= 0·0029). In multivariate logistic regression analysis, PNH clone presence (odds ratio 2·56, = 0·0180) and baseline absolute reticulocyte count (ARC) ≥30 × 109/l (odds ratio 5·19, = 0·0011) were independent predictors of response to treatment. Stratification according to PNH positivity and ARC ≥30 × 109/l showed significant distinctions for cumulative incidence of response, overall and failure‐free survival. The results of this prospective study confirmed the favourable prognostic value of PNH clone presence in the setting of IST for AA.  相似文献   
948.
949.
950.

Introduction

Intracoronary (IC) papaverine which is one of the commonly used agents for Fractional Flow Reserve (FFR) estimation has been reported to cause transient ST elevation in some patients. This phenomenon has not been systematically studied.

Material and methods

This is a prospective, observational study. Consecutive patients, who underwent FFR at our institute using IC papaverine from May 2012 to April 2013, were included. FFR was done when clinically indicated. The procedure involved administration of 20 mg papaverine (Paparin® – Troikaa, Ahmedabad) as a fast bolus by intracoronary route followed by a 10 cc contrast flush, following which pressure measurements were made. Continuous ECG recording by Philips Hemodynamic Laboratory was obtained for all patients throughout the procedure. Post procedure, they were observed for any delayed effects and eventual outcome was documented. Fischer''s mid-p test was used for statistical analysis.

Result

Twenty-five patients (18 males, 7 females, mean age 57.9 ± 20 years) underwent FFR using Papaverine. The mean LVEF was (51 ± 15%). Fourteen patients (56%) developed transient ST elevation ≥0.5 mm in one or more leads which resolved spontaneously in all cases without any sequelae. The presence of a significant lesion either in the coronary artery being evaluated or in a remote coronary artery did not predict the ST elevation. 70.5% of diabetics (p = 0.02), 75% of hypertensives (p = 0.008) and 75% of patients with LVH (p = 0.008) had ST elevation. None of the 5 patients without any one of these comorbidities showed ST elevation.

Conclusion

Transient ST elevation occurs in a significant proportion of cases receiving IC papaverine which is not associated with any adverse clinical outcomes. Micro vascular dysfunction is the most likely mechanism of this phenomenon.  相似文献   
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