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71.
Matthias Meyer Lukas Parik Felix Greimel Tobias Renkawitz Joachim Grifka Markus Weber 《The Journal of arthroplasty》2021,36(5):1533-1542
BackgroundModels for risk stratification and prediction of outcome, such as the Charlson Comorbidity Index (CCI), the Elixhauser Comorbidity Method (ECM), the 5-factor modified Frailty Index (mFI-5), and the Hospital Frailty Risk Score (HFRS) have been validated in orthopedic surgery. The aim of this study is to compare the predictive power of these models in total hip and knee replacement.MethodsIn a retrospective analysis of 8250 patients who had undergone total joint replacement between 2011 and 2019, CCI, ECM, mFI-5, and HFRS were calculated for each patient. Receiver operating characteristic curve plots were generated and the area under the curve (AUC) was compared between each score with regard to adverse events such as transfusion, surgical, medical, and other complications. Multivariate logistic regression models were used to assess the relationship among risk stratification models, demographic factors, and postoperative adverse events.ResultsIn prediction of surgical complications, HFRS performed best (AUC: 0.719, P < .001), followed by ECM (AUC: 0.578, P < .001), mFI-5 (AUC: 0.564, P = .003), and CCI (AUC: 0.555, P = .012). With regard to medical complications, other complications, and transfusion, HFRS also was superior to ECM, mFI-5, and CCI. Multivariate logistic regression analyses revealed HFRS as an independent risk stratification model associated with all captured adverse events (P ≤ .001).ConclusionThe HFRS is superior to current risk stratification models in the context of total joint replacement. As the HRFS derives from routinely collected administrative data, healthcare providers can identify at-risk patients without additional effort or expense. 相似文献
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74.
目的 探讨健康教练教育对提升预防性肠造口患者自我护理能力的作用.方法 将110例直肠癌行预防性肠造口的患者随机分为干预组和对照组各55例.对照组采取个体宣教,每周2次集中授课,1次理论授课,1次实践操作,每月定期随访等常规健康教育;干预组在此基础上采取健康教练教育进行造口管理.比较两组手术前后的肠造口自我护理能力和术后造口并发症发生率.结果 术后第5天、术后1个月末、术后3个月末干预组自我护理能力总分优于同期的对照组(均P<0.01).术后1个月、术后3个月干预组的刺激性皮炎发生率显著低于对照组(均P<0.01).结论 健康教练教育能提高预防性肠造口患者的自我护理能力,降低造口并发症的发生. 相似文献
75.
目的探讨miR-21对骨质疏松小鼠骨髓基质细胞(BMSCs)增殖的影响。方法采用双侧卵巢切除法构建骨质疏松小鼠模型(VOX),分离、培养、纯化小鼠BMSCs并采用si PORT Neo FX转染pre-miR-21、pre-miR-negative control(pre-miR-NC)、antmiR-21、ant-miR-negative control(ant-miR-NC)并进行RT-PCR验证,MTT法检测小鼠BMSCs增殖情况、茜素红与碱性磷酸酶染色法检测小鼠BMSCs成骨能力、Western-blotting检测细胞增殖、成骨分化相关蛋白水平。结果骨质疏松症小鼠BMSCs中miR-21相对表达水平低于Ctrl组(P0.05),OVX-pre-miR-21组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均高于OVX-pre-miR-NC组(P0.05),OVX-premiR-NC组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于Ctrl-pre-miR-NC(P0.05); OVX-ant-miR-21组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于OVX-ant-miR-NC组(P0.05),OVX-ant-miR-NC组BMSCs中miR-21相对表达水平、细胞增殖、PCNA水平、Ki-67水平、ALP染色程度、ALP活性、茜素红染色程度、Runx2水平、Osterix水平均显著低于Ctrl-ant-miR-NC(P0.05)。结论提高miR-21表达水平可促进骨质疏松小鼠BMSCs增殖能力与成骨分化能力。 相似文献
76.
Attentional modulation of SSVEP power depends on the network tagged by the flicker frequency 总被引:1,自引:0,他引:1
Modulation of the steady-state visual evoked potential (SSVEP) by attention was studied in detail using 15 'tag' frequencies in the range of 2.5-20 Hz. The stimuli were two series of random disc search arrays superimposed on two concentric color-marked annuli respectively. Two series of arrays were updated independently; one updated at one fixed frequency (flicker) and the other updated randomly according to a white noise distribution (random broadband flicker, rbbf). On each trial, the observer was instructed to attend one annulus and to detect a target (a triangle) that occasionally appeared in a random disc array in the attended annulus. The SSVEP results show that the choice of flicker frequency selects which cortical network synchronizes to the flicker two distinct cortical networks showed different effects of attention. SSVEP power and the effects of attention on SSVEP power strongly depend on both flicker frequency and radial position of rbbf annulus. At flicker frequencies in the delta band (2-4 Hz), and in the upper alpha band (10-11 Hz), an occipital-frontal network appears to phase-lock to the flicker when attending to the flicker, increasing the magnitude of the SSVEP. At flicker frequencies in the lower alpha band (8-10 Hz), a global response to a peripheral flickering stimulus, that includes parietal cortex and posterior frontal cortex, has higher amplitude when attention is directed away from the flickering peripheral stimulus and towards a competing rbbf stimulus in the fovea. Increases in SSVEP power when attention is directed to peripheral flicker are always associated with increases in phase locking. By contrast, at frequencies in the lower alpha band, increases in SSVEP power when attention is directed away from the flicker and towards foveal stimuli are not associated with changes in phase-locking. Thus, whether attention to a flicker stimulus increases or decreases SSVEP amplitude and phase locking depends on which of two cortical networks, which have distinct spatial and dynamic properties, is selected by the flicker frequency. 相似文献
77.
A. Chuan B. Jeyaratnam G. Iohom G. Shorten P. Lee S. Miglani K. Kwofie J. Szerb A. U. Niazi R. Jin T. Jen C. J. McCartney R. Ramlogan the Education in Regional Anaesthesia Collaboration Group 《Anaesthesia》2021,76(7):911-917
The learning curve for novices developing regional anaesthesia skills, such as real-time ultrasound-guided needle manipulation, may be affected by innate visuospatial ability, as this influences spatial cognition and motor co-ordination. We conducted a multinational randomised controlled trial to test if novices with low visuospatial ability would perform better at an ultrasound-guided needling task with deliberate practice training than with discovery learning. Visuospatial ability was evaluated using the mental rotations test-A. We recruited 140 medical students and randomly allocated them into low-ability control (discovery learning), low-ability intervention (received deliberate practice), high-ability control, and high-ability intervention groups. Primary outcome was the time taken to complete the needling task, and there was no significant difference between groups: median (IQR [range]) low-ability control 125 s (69–237 [43–600 s]); low-ability intervention 163 s (116–276 [44–600 s]); high-ability control 130 s (80–210 [41–384 s]); and high-ability intervention 177 s (113–285 [43–547 s]), p = 0.06. No difference was found using the global rating scale: mean (95%CI) low-ability control 53% (95%CI 46–60%); low-ability intervention 61% (95%CI 53–68%); high-ability control 63% (95%CI 56–70%); and high-ability intervention 66% (95%CI 60–72%), p = 0.05. For overall procedure pass/fail, the low-ability control group pass rate of 42% (14/33) was significantly less than the other three groups: low-ability intervention 69% (25/36); high-ability control 68% (25/37); and high-ability intervention 85% (29/34) p = 0.003. Further research is required to determine the role of visuospatial ability screening in training for ultrasound-guided needle skills. 相似文献
78.
目的研究BRP44高表达的人前列腺癌细胞PC3细胞系(雄激素非依赖性前列腺癌细胞株)细胞的生物学性状的影响,以了解其在人前列腺癌发生发展中可能的机制和作用。方法将已转染BRP44的PC3细胞提取其RNA,进而行Northern Blot检测证明其高表达,用Alamar Blue检测BRP44高表达的阳性细胞生长情况,流式细胞仪检测其细胞周期变换,采用改良的Transweu侵袭小室方法检测细胞侵袭能力。结果BRP44高表达的PC3细胞增殖速度较转染空载体的PC3细胞和正常PC3细胞快,差异有统计学意义(P〈0.05)。在体外细胞移动实验中,BRP44高表达的PC3细胞也较另两组细胞表现出更强的穿膜能力、侵袭力(P〈0.01)。结论BRP44表达增高与人前列腺癌细胞的恶性表型具有密切相关性,BRP44可能在人前列腺癌的发生、发展中发挥重要作用。 相似文献
79.
目的:研究超低频经颅磁刺激(TMS)对脑缺血大鼠认知功能的影响并探讨其机制。方法将60只健康大鼠分为4组(各15只):A组(假手术组),B组(模型组),C组(TMS组)和D组(TMS+H89组)。比较各组大鼠的逃避潜伏时间、跨越原平台次数及血管内皮生长因子(VEGF)、脑源性神经营养因子(BDNF)和巢蛋白(nestin)的表达水平。结果A组大鼠逃避潜伏期为(16.31±2.33)s,跨越原平台次数为(8.02±1.76)次;B组大鼠逃避潜伏期为(57.14±2.89)s,跨越原平台次数为(3.15±0.88)次;C组大鼠逃避潜伏期为(29.18±1.95)s,跨越原平台次数为(5.44±0.75)次;D组大鼠逃避潜伏期为(45.87±2.06)s,跨越原平台次数为(4.16±1.02)次。与A组比较,B、C、D组大鼠的逃避潜伏期明显延长,且B组长于D组及C组,差异均有统计学意义(P<0.05);大鼠的跨越原平台次数明显减少,且B组少于D组及C组,差异均有统计学意义(P<0.05)。各组大鼠VECF、BDNF和nestin表达水平比较,差异均有统计学意义(P<0.05)。结论低频TMS可以明显改善脑缺血大鼠的认知功能,其作用与环磷腺苷效应元件结合蛋白及其下游基因(VEGF、BDNF)的表达有关。 相似文献
80.
目的探究不同剂量微生物源性抗氧化剂对小鼠睡眠及其抗氧化性能的影响。方法 60只雄性昆明小鼠随机分为4组,低、中、高剂量组分别灌喂0.5 g/kg体重、1.0 g/kg体重和1.5 g/kg体重微生物源性抗氧化剂,对照组使用生理盐水进行灌胃,试验期30 d。在末次灌胃后,各组动物腹腔注射戊巴比妥钠,通过翻正反射实验观察小鼠睡眠状况,并在结束后,检测小鼠血清抗氧化性能。结果与低、高剂量组相比,中剂量组的微生物源性抗氧化剂可以显著延长戊巴比妥钠睡眠时间(P0.05)。与对照组,低,高剂量组相比,中剂量组极显著提高GSH-Px活力(P0.01)、显著提高SOD活力(P0.05)。与对照组相比,中剂量组MDA和8-ISO-PGF2α含量有显著降低(P0.05)。结论提示微生物源性抗氧化剂有促进小鼠的睡眠、提高机体抗氧化能力的作用,且在1.0g/kg体重剂量下效果最显著。 相似文献