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1.
ObjectiveTo determine the long-term cardiovascular disease risk of astronauts with spaceflight exposure compared with a well-matched cohort.MethodsNational Aeronautics and Space Administration (NASA) astronauts are selected into their profession based upon education, unique skills, and health and are exposed to cardiovascular disease risk factors during spaceflight. The Cooper Center Longitudinal Study (CCLS) is a generally healthy cohort from a preventive medicine clinic in Dallas, Texas. Using a matched cohort design, astronauts who were selected beginning April 1, 1959, (and each subsequent selection class through 2009) and exposed to spaceflight were matched to CCLS participants who met astronaut selection criteria; 1514 CCLS participants matched to 303 astronauts in a 5-to-1 ratio on sex, date of birth, and age. The outcome of cardiovascular mortality through December 31, 2016, was determined by death certificate or National Death Index.ResultsThere were 11 deaths caused by cardiovascular disease (CVD) among astronauts and 46 among CCLS participants. There was no evidence of increased mortality risk in astronauts (hazard ratio [HR]=1.10; 95% confidence interval [CI], 0.50 to 2.45) with adjustment for baseline cardiovascular covariates. However, the secondary outcome of CVD events showed an increased adjusted risk in astronauts (HR=2.41; 95% CI, 1.26 to 4.63).ConclusionNo increased risk of CVD mortality was observed in astronauts with spaceflight exposure compared with a well-matched cohort, but there was evidence of increased total CVD events. Given that the duration of spaceflight will increase, particularly on missions to Mars, continued surveillance and mitigation of CVD risk is needed to ensure the safety of those who venture into space.  相似文献   
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Introduction and objectivesOptimal treatment of hepatocellular carcinoma (HCC) involving portal vein tumor thrombus (PVTT) remains controversial.Materials and methodsA total of 627 HCC patients with PVTT after initial treatment with one of the following at Affiliated Tumor Hospital of Guangxi Medical University: liver resection (LR, n = 225), transarterial chemoembolization (TACE, n = 298) or sorafenib (n = 104) were recruited and randomly divided into the training cohort (n = 314) and internal validation cohort (n = 313). Survival analysis were repeated after stratifying patients by Cheng PVTT type.ResultsResection led to significantly higher OS than the other two treatments among patients with type I or II PVTT. TACE worked significantly better than the other two treatments for patients with type III. All three treatments were associated with similar OS among patients with type IV. These findings were supported by the internal validation cohort.ConclusionsOur results suggest that the optimal treatment for HCC involving PVTT depends on the type of PVTT. LR may be more appropriate for type I or II PVTT; TACE, for type III Sorafenib may be more appropriate than invasive treatments for patients with type IV PVTT.  相似文献   
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闫铭  李苇航  丁子毅  王栋  石全  张世磊 《骨科》2022,13(5):433-436
目的 探讨以问题为基础的学习(problem-based learning,PBL)联合以案例为基础的学习(case-based learning,CBL)在脊柱外科医学生带教中的教学意义及优势。方法 选取2021年3月至2021年9月在我院脊柱外科实习的53名2017级本科生,随机将其分为传统教学组(简称传统组,28例)和教学方法联合组(简称联合组,25例)进行实习带教,其中传统组男15人,女13人,年龄为(22.04±0.58)岁。联合组男13人,女12人,年龄为(22.36±0.64)岁。实习结束后通过出科考核的方式对学生理论知识及临床实践能力进行考核。同时派发问卷调查,评价老师教学水平及对课程设计满意情况。结果 联合组理论知识及临床实践能力均优于传统组,两组间差异有统计学意义(P<0.05)。另外,从学生反馈来看,联合组学生对老师教学形式及课程设计的满意度更高。结论 教学方法的组合更有利于调动学生主观能动性及主动学习的积极性,培养学习兴趣,提高学习效率。从而更好地掌握脊柱外科专业知识及临床技能,提高本科生及规培生培养质量。  相似文献   
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BackgroundThis study aimed to assess inpatient prevalence, characteristics, outcomes, and resource utilization of hospitalization for methanol intoxication in the United States.Materials and MethodsA total of 603 hospitalized patients with a primary diagnosis of methanol intoxication from 2003 to 2014 were identified in the National Inpatient Sample database. The inpatient prevalence, clinical characteristics, treatments, outcomes, resource utilization, were investigated. Multivariable logistic regression was performed to identify factors independently associated with in-hospital mortality.ResultsThe overall inpatient prevalence of methanol intoxication among hospitalized patients was 6.4 cases per 1,000,000 admissions in the United States. The mean age was 38±18 (range 0–86) years. 44% used methanol for suicidal attempts. 20% of admissions required mechanical ventilation, and 40% required renal replacement therapy. The three most common complications were metabolic acidosis (44%), hypokalemia (18%), and visual impairment or optic neuritis (8%). The three most common end-organ failures were renal failure (22%), respiratory failure (21%), and neurological failure (17%). 6.5% died in the hospital. Factors associated with increased in-hospital mortality included alcohol drinking, hypernatremia, renal failure, respiratory failure, circulatory failure, and neurological failure. The mean length of hospital stay was 4.0 days. The mean hospitalization cost per patient was $43,222ConclusionThe inpatient prevalence of methanol intoxication in the United States was 6.4 cases per 1,000,000 admissions. The risk of in-hospital mortality mainly depended on the number of end-organ failures.  相似文献   
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目的探寻冠状动脉慢血流现象(CSFP)的临床危险因素,了解冠状动脉形态对心肌梗死溶栓治疗试验(TIMI)血流的影响,推测CSFP的发病机制。方法回顾性收集2017年1月至2019年7月于兰州大学第一医院心脏中心行冠状动脉造影无狭窄病变的患者256例,根据TIMI血流帧数将其中血流减慢的患者设为CSFP组(100例),将血流正常患者设为对照组(156例),按年龄和性别匹配。收集患者临床数据和冠状动脉造影数据,采用二元logistic回归模型分析CSFP的危险因素,并采用Pearson相关分析检验冠状动脉形态学参数与平均校正的TIMI帧数(cTFC)的相关性。结果CSFP组同型半胱氨酸[(22.07±7.27)mmol/L比(18.16±6.63)mmol/L]、中性粒细胞百分比[(44.40±15.60)%比(35.43±12.49)%]、淋巴细胞百分比[3.65%(1.32%,24.65%)比1.80%(1.02%,6.22%)]、平均血小板体积(MPV)[(13.17±1.82)fl比(12.20±1.57)fl]、血小板分布宽度(PDW)[(14.17±2.17)f l比(13.21±2.42)f l]与对照组相比更高,三酰甘油[(3.05±1.37)mmol/L比(3.44±1.36)mmol/L]、纤维蛋白原[(2.65±0.68)g/L比(2.86±0.66)g/L]与对照组相比更低,术中血压更低,冠状动脉平均直径更大,平均远端分支数更少,差异均有统计学意义(均P<0.05)。二元logistic回归模型拟合显示:同型半胱氨酸(OR 1.077,95%CI 1.034~1.123,P<0.001)、中性粒细胞百分比(OR 1.064,95%CI 1.032~1.097,P<0.001)、PDW(OR 1.194,95%CI 1.051~1.356,P=0.006)、MPV(OR 1.338,95%CI 1.127~1.588,P=0.001)是预测CSFP的独立危险因素。相关性分析显示,冠状动脉平均直径与平均cTFC呈显著正相关(r=0.583,P<0.05);冠状动脉平均远端分支数与平均cTFC呈显著负相关(r=-0.508,P<0.05)。结论同型半胱氨酸、中性粒细胞百分比、PDW和MPV是预测CSPF的独立危险因素。冠状动脉平均直径和远端分支数均与冠状动脉平均cTFC密切相关。炎症可能是CSFP发生的关键机制。  相似文献   
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Objectives: To evaluate the safety of acute ischemic stroke (AIS) therapy in patients with infective endocarditis (IE) with intravenous thrombolysis (IVT) or endovascular therapy (EVT) such as mechanical thrombectomy. Methods: We conducted a retrospective study of patients who underwent AIS therapy with IVT or EVT at a tertiary referral center from 2013 to 2017, that were later diagnosed with acute IE as the causative mechanism. We then performed a systematic review of reports of acute ischemic reperfusion therapy in IE since 1995 for their success rates in terms of neurological outcome, and mortality, and their risk of hemorrhagic complication. Results: In the retrospective portion, 8 participants met criteria, of whom 4 received IVT and 4 received EVT. Through systematic review, 24 publications of 32 participants met criteria. Combined, a total of 40 participants were analyzed: 18 received IVT alone, 1 received combined IVT plus EVT, and 21 received EVT alone. IVT compared to EVT were similar in rates of good neurologic outcomes (58% versus 76%, P= .22) and mortality (21% versus 19%, P= .87), but had higher post-therapy intracranial hemorrhage (63% versus 18% [P= .006]). Conclusion: IV thrombolysis has a higher rate of post-therapy intracranial hemorrhage compared to EVT. EVT should be considered as first-line AIS therapy for patients with known, or suspected, IE who present with a large vessel occlusion.  相似文献   
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ObjectivesTo identify factors associated with 30-day all-cause readmission rates in surgical patients discharged to skilled nursing facilities (SNFs), and derive and validate a risk score.DesignRetrospective cohort.Setting and participantsPatients admitted to 1 tertiary hospital's surgical services between January 1, 2011, and December 31, 2014 and subsequently discharged to 110 SNFs within a 25-mile radius of the hospital. The first 2 years were used for the derivation set and the last 2 for validation.MethodsData were collected on 30-day all cause readmissions, patient demographics, procedure and surgical service, comorbidities, laboratory tests, and prior health care utilization. Multivariate regression was used to identify risk factors for readmission.ResultsDuring the study period, 2405 surgical patients were discharged to 110 SNFs, and 519 (21.6%) of these patients experienced readmission within 30 days. In a multivariable regression model, hospital length of stay [odds ratio (OR) per day: 1.03, 95% confidence interval (CI) 1.02-1.04], number of hospitalizations in past year (OR 1.24 per hospitalization, 95% CI 1.18-1.31), nonelective surgery (OR 1.33, 95% CI 1.18-1.65), low-risk service (orthopedic/spine service) (OR 0.32, 95% CI 0.25-0.42), and intermediate-risk service (cardiothoracic surgery/urology/gynecology/ear, nose, throat) (OR 0.69, 95% CI 0.53-0.88) were associated with all-cause readmissions. The model had a C index of 0.71 in the validation set. Using the following risk score [0.8 × (hospital length of stay) + 7 × (number of hospitalizations in past year) +10 for nonelective surgery, +36 for high-risk surgery, and +20 for intermediate-risk surgery], a score of >40 identified patients at high risk of 30-day readmission (35.8% vs 12.6%, P < .001).Conclusions/ImplicationsAmong surgical patients discharged to an SNF, a simple risk score with 4 parameters can accurately predict the risk of 30-day readmission.  相似文献   
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