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《The Journal of thoracic and cardiovascular surgery》2023,165(1):149-158.e4
BackgroundCoronary artery bypass grafting (CABG) improves survival in patients with heart failure and severely reduced left ventricular systolic function (LVEF). Limited data exist regarding adverse cardiovascular event rates after CABG in patients with heart failure with midrange ejection fraction (HFmrEF; LVEF > 40% and < 55%).MethodsWe analyzed data on isolated CABG patients from the Veterans Affairs national database (2010-2019). We stratified patients into control (normal LVEF and no heart failure), HFmrEF, and heart failure with reduced LVEF (HFrEF) groups. We compared all-cause mortality and heart failure hospitalization rates between groups with a Cox model and recurrent events analysis, respectively.ResultsIn 6533 veterans, HFmrEF and HFrEF was present in 1715 (26.3%) and 566 (8.6%) respectively; the control group had 4252 (65.1%) patients. HFrEF patients were more likely to have diabetes mellitus (59%), insulin therapy (36%), and previous myocardial infarction (31%). Anemia was more prevalent in patients with HFrEF (49%) as was a lower serum albumin (mean, 3.6 mg/dL). Compared with the control group, a higher risk of death was observed in the HFmrEF (hazard ratio [HR], 1.3 [1.2-1.5)] and HFrEF (HR, 1.5 [1.2-1.7]) groups. HFmrEF patients had the higher risk of myocardial infarction (subdistribution HR, 1.2 [1-1.6]; P = .04). Risk of heart failure hospitalization was higher in patients with HFmrEF (HR, 4.1 [3.5-4.7]) and patients with HFrEF (HR, 7.2 [6.2-8.5]).ConclusionsHeart failure with midrange ejection fraction negatively affects survival after CABG. These patients also experience higher rates myocardial infarction and heart failure hospitalization. 相似文献
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A typical time series in functional magnetic resonance imaging (fMRI) exhibits autocorrelation, that is, the samples of the time series are dependent. In addition, temporal filtering, one of the crucial steps in preprocessing of functional magnetic resonance images, induces its own autocorrelation. While performing connectivity analysis in fMRI, the impact of the autocorrelation is largely ignored. Recently, autocorrelation has been addressed by variance correction approaches, which are sensitive to the sampling rate. In this article, we aim to investigate the impact of the sampling rate on the variance correction approaches. Toward this end, we first derived a generalized expression for the variance of the sample Pearson correlation coefficient (SPCC) in terms of the sampling rate and the filter cutoff frequency, in addition to the autocorrelation and cross‐covariance functions of the time series. Through simulations, we illustrated the importance of the variance correction for a fixed sampling rate. Using the real resting state fMRI data sets, we demonstrated that the data sets with higher sampling rates were more prone to false positives, in agreement with the existing empirical reports. We further demonstrated with single subject results that for the data sets with higher sampling rates, the variance correction strategy restored the integrity of true connectivity. 相似文献
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《Allergology international》2022,71(4):432-436
Steroid hormones, especially glucocorticoids, androgens, and estrogens, have profound influence on immunity. Recent studies using cell-type specific steroid hormone receptor-deficient mice have revealed the precise roles of some of these hormones in the immune system. Glucocorticoids are known to have strong anti-inflammatory and immunosuppressive effects and pleiotropic effects on innate and adaptive immune responses. They suppress the production of inflammatory cytokines by macrophages and DCs and the production of IFN-γ by NK cells, thus inhibiting innate immunity. By contrast, glucocorticoids enhance the immune response by inducing the expression of IL-7R and CXCR4 in T cells and the accumulation of T cells in lymphoid organs in accordance with the diurnal change of the glucocorticoid concentration. Thus, glucocorticoids suppress innate immunity but enhance adaptive immunity. Androgens suppress the homeostasis and activation of ILC2s and the differentiation of Th2 and Th17 cells and enhance the suppressive function of Tregs, thereby alleviating allergic airway inflammation. Thus, these steroid hormones have pleiotropic functions in the immune system. Further investigations are awaited on the regulation of immunity and allergy by estrogens using cell-specific steroid hormone receptor-deficient mice. 相似文献
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目的 探讨丙泊酚复合瑞芬太尼喉罩全身麻醉(全麻)的效果。方法 62例腹腔镜、泌尿科、骨科、肛肠科、妇科等手术治疗的患者,随机分为实验组和对照组,每组31例。对照组采用常规气管插管静脉复合全麻,实验组给予靶控输注丙泊酚复合瑞芬太尼喉罩全麻。比较两组患者插入喉罩(插管)、插管1 min、插管3 min、拔出喉罩(拔管)1 min、拔管3 min时心率(HR)和平均动脉压(MAP)水平;不良反应发生情况、麻醉效果;全麻起效时间、维持全麻时间、术后苏醒时间。结果 实验组插管时、插管1 min、插管3 min、拔管1 min、拔管3 min的HR水平分别为(77.52±6.36)、(73.26±5.56)、(72.01±4.69)、(75.35±7.63)、(72.34±6.79)次/min,均低于对照组的(92.34±7.85)、(87.97±5.25)、(78.85±5.20)、(95.69±9.21)、(85.63±7.43)次/min,差异均具有统计学意义(P<0.05)。实验组插管时、插管1 min、插管3 min、拔管1 min、拔管3 min的MAP水平分别为(90.25±6.73)、(87.65±7.98)、(88.79±7.65)、(88.09±5.61)、(88.52±5.16)mm Hg(1 mm Hg=0.133 kPa),均低于对照组的(109.51±7.85)、(103.27±12.43)、(102.52±8.21)、(106.74±7.68)、(104.62±7.71)mm Hg,差异均具有统计学意义(P<0.05)。实验组不良反应发生率3.23%低于对照组的19.35%,差异具有统计学意义(P<0.05)。实验组麻醉总有效率96.77%均高于对照组的80.65%,差异均具有统计学意义(P<0.05)。实验组全麻起效、维持全麻、术后苏醒时间分别为(1.61±0.23)、(100.59±6.72)、(17.99±3.52)min,均短于对照组的(2.93±0.41)、(123.61±7.85)、(36.87±4.16)min,差异均具有统计学意义(P<0.05)。结论 针对腹腔镜等手术患者应用丙泊酚复合瑞芬太尼喉罩全麻对血液动力学影响小,不良反应发生率低,麻醉效果良好,降低对机体损伤,值得推广应用。 相似文献
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Yosuke Homma Takashi Shiga Hiraku Funakoshi Dai Miyazaki Atsushi Sakurai Yoshio Tahara Ken Nagao Naohiro Yonemoto Arino Yaguchi Naoto Morimura 《The American journal of emergency medicine》2019,37(2):241-248