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《The Journal of thoracic and cardiovascular surgery》2023,165(1):94-103.e24
ObjectiveNew-onset postoperative atrial fibrillation (POAF) after cardiac surgery is common, with rates up to 60%. POAF has been associated with early and late stroke, but its association with other cardiovascular outcomes is less known. The objective was to perform a meta-analysis of the studies reporting the association of POAF with perioperative and long-term outcomes in patients with cardiac surgery.MethodsWe performed a systematic review and a meta-analysis of studies that presented outcomes for cardiac surgery on the basis of the presence or absence of POAF. MEDLINE, EMBASE, and the Cochrane Library were assessed; 57 studies (246,340 patients) were selected. Perioperative mortality was the primary outcome. Inverse variance method and random model were performed. Leave-one-out analysis, subgroup analyses, and metaregression were conducted.ResultsPOAF was associated with perioperative mortality (odds ratio [OR], 1.92; 95% confidence interval [CI], 1.58-2.33), perioperative stroke (OR, 2.17; 95% CI, 1.90-2.49), perioperative myocardial infarction (OR, 1.28; 95% CI, 1.06-1.54), perioperative acute renal failure (OR, 2.74; 95% CI, 2.42-3.11), hospital (standardized mean difference, 0.80; 95% CI, 0.53-1.07) and intensive care unit stay (standardized mean difference, 0.55; 95% CI, 0.24-0.86), long-term mortality (incidence rate ratio [IRR], 1.54; 95% CI, 1.40-1.69), long-term stroke (IRR, 1.33; 95% CI, 1.21-1.46), and longstanding persistent atrial fibrillation (IRR, 4.73; 95% CI, 3.36-6.66).ConclusionsThe results suggest that POAF after cardiac surgery is associated with an increased occurrence of most short- and long-term cardiovascular adverse events. However, the causality of this association remains to be established. 相似文献
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目的:探讨建立一种放射治疗全身器官剂量数据库平台的可行性。方法:使用基于深度学习的自动勾画软件DeepViewer?1例食管癌患者的全身CT上勾画全身器官,然后利用基于GPU加速的蒙特卡罗软件ARCHER计算相应的器官剂量分布,最后利用Lyman-Kutcher-Burman(LKB)模型评估放疗患者正常组织并发症概率(NTCP)。结果:针对该病例,成功建立基于DeepViewer?ARCHER和LKB模型的全身器官剂量数据库,发现距离靶区越近的器官剂量越大,其中心脏与靶区间距离最小,剂量为14.11 Gy,但因其模型参数特殊,通过LKB模型计算的NTCP为0.00%;左、右肺的剂量分别为3.19和1.16 Gy,但是NTCP值却很大,分别为2.13%和1.60%。对于距离靶区较远的头颈部器官(视交叉、视神经和眼)和腹部器官(直肠、膀胱和股骨头)剂量分别约为9和2 mGy,并且NTCP均近似为0.00%。结论:研究结果证明通过自动勾画软件DeepViewer?蒙特卡罗软件ARCHER和LKB模型建立全身器官剂量数据库的可行性。 相似文献
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J. Viac C. Goujon L. Misery V. Staniek M. Faure D. Schmitt A. Claudy 《Photodermatology, photoimmunology & photomedicine》1997,13(3):103-108
Ultraviolet radiation B (UVB) on the skin induces erythema, inflammation and modifications of the immune system. These changes have been reported after excessive short-term or long-term exposure to broad spectrum UVB. In this study, we examined the effects of local repetitive UVB irradiation of 311 nm wavelength on the skin of seven young volunteers. Skin biopsies were taken before and after UVB irradiation, and we immunohistochemically analyzed the expression of CD1a and HLA-DR antigens of Langerhans cells (LC), the possible infiltration of dermis/epidermis by CD11b macrophages, the modifications or the induction of intercellular adhesion molecule-1 (ICAM-1), E-selectin and vascular cell adhesion molecule-1 (VCAM-1) involved in the binding of leukocytes to the endothelial surface and the development of perivascular infiltrates of LFA-1+ mononuclear cells. We also determined the expression of substance P receptors (SPR) using biotinylated substance P (SPB). Exposure of UVB 311 nm induced a drastic reduction of CD1a+ cells and a moderate increase of HLA-DR+ dendritic cells in the epidermis without infiltration by CD11b macrophages. An increase of the binding of SPB to upper layer epidermal cells was noted in five of seven biopsies. In the dermis, vessel-associated ICAM-1 expression increased and an induction of E-selectin occurred on nearly 20 to 40% of endothelial cells, but VCAM-1 expression remained undetectable. The percentage of LFA-1+ cells did not change significantly after irradiation. These observations may be compatible with a selective role of UVB 311 nm on the skin immune response. 相似文献
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目的:研究正常[牙合]者瞳孔间距(Interpupillary Distance,IPD)与咬合垂直距离(Occlusal Vertical Dimension,OVD)的关系。方法:对116名福建籍青年正常[牙合]者测量其OVD与IPD,并进行两者相关回归分析。结果:总样本的OVD均值为65.35mm±4.70mm,IPD均值为63.98mm±3.26mm,男性正常[牙合]者OVD均值为68.16mm±4.23mm,IPD均值为65.46mm±2.96mm,女性正常[牙合]者的OVD均值为63.22mm±3.86mm,IPD均值为62.86mm±3.05mm;总样本的IPD与OVD的相关系数r=0.633,男性样本的IPD与0VD的相关系数r=0.563,女性样本的IPD与OVD的相关系数r=0.531。结论:IPD与OVD间存在显著相关性,IPD可以作为需咬合重建患者确定其OVD的参考指标。 相似文献
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采用快速粘度分析仪(RVA)研究了食盐对18种普通玉米杂交种淀粉糊化性质的影响。结果表明:食盐显著降低了所有普通玉米杂交种淀粉的峰值、破损值和回生值;提高了谷值、终粘度、出峰时间和成糊温度。但对不同的普通玉米杂交种淀粉的糊化性质的影响程度有显著差别。随着食盐溶液质量分数的增加,普通玉米杂交种淀粉的谷值、终粘度、出峰时间和成糊温度也逐渐增加,破损值和回生值则显著降低,峰值受食盐溶液质量分数的影响很小。 相似文献
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Cancer chemotherapy with the application of several drugs is studied. The negative and inhibiting effect of the tumour on normal cells is taken into account. Under certain hypotheses, we determine the optimal regimen that minimizes the tumour burden at the end of a fixed period of therapy while maintaining several normal cell populations above prescribed levels. More precisely, it is demonstrated that the optimal drug administration corresponds to the strategy of intensive chemotherapy. 相似文献
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层流洁净手术室空气日常监测方法效果观察 总被引:2,自引:0,他引:2
目的探讨层流洁净手术室空气日常监测有效方法。方法对层流洁净手术室百级、千级、万级各1间手术间,分别按《医药卫生洁净室(区)沉降菌的测试方法》GB/T16294-1996、《医药消毒卫生标准》GB/T15982-1995,在相同的温度、湿度下,共计8d,专人定时静态下,采用多点布控法(多点布控组)与常规布控法(常规布控组),分两组不同高度进行空气沉降法采样,30min后进行检测。结果多点布控与常规布控采样,细菌菌落数均未超标;无致病菌检出。多点布控组与常规布控组监测结果经t检验,有显著性差异(P<0.01)。多点布控采样效果优于常规布控组。手术区在0.8m、1.2m高度多点布控采样检测结果无细菌生长;周边区地面上采样与周边高度0.8m处采样监测结果经χ2检验,有显著性差异(P<0.05),多点布控周边区地面上采样阳性率高于周边高度0.8m采样。常规布控0.8m高度采样阳性率高于1.2m高度采样,采样监测结果经χ2检验,无显著性差异(P>0.05)。结论采用多点布控,手术区0.8 ̄1.2m高度、周边地面上采样进行空气沉降法监测是洁净手术室空气日常监测的有效方法。 相似文献