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ObjectivesTo determine whether differences in landing force and asymmetry of landing force exist between gymnasts at the time of data collection versus those that subsequently experienced an ankle injury 12-months later.Study designProspective longitudinal observational design with baseline measures and 12 month follow up.SettingBritish Gymnastics National Training Centre.ParticipantsThirty-two asymptomatic elite level gymnasts from three artistic gymnastic squads (n = 15 senior female, n = 10 junior female and n = 7 senior male).Main outcome measuresA modified drop land task was used to quantify measures of landing performance. Peak Vertical Ground Reaction Force (PVGRF) was used to measure landing force. The level of inter-limb asymmetry of landing force was calculated using the Limb Symmetry index (LSI). Other measures included injury incidence and percentage coefficient of variation (% CV).ResultsThere was no statistical difference for landing force (p = 0.481) and asymmetry of landing force (p = 0.698) when comparing injured and non-injured gymnasts. Most participants (69%) demonstrated inter-limb asymmetry of landing forces.ConclusionsOur findings observed inter-limb asymmetry of landing force in injured gymnasts, although uninjured gymnasts also exhibited asymmetry of landing force. Both magnitude of landing force and inter-limb asymmetries of landing force failed to identify the risk of ankle injury. 相似文献
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《The Journal of thoracic and cardiovascular surgery》2023,165(2):750-760.e5
ObjectivesThe reduction of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery using an oxygen delivery-guided perfusion strategy (oxygen delivery strategy) for cardiopulmonary bypass management compared with a fixed flow perfusion (conventional strategy) remains controversial. The purpose of this study was to determine whether a oxygen delivery strategy would reduce the incidence of postoperative acute kidney injury in patients undergoing cardiopulmonary bypass surgery.MethodsWe randomly enrolled 300 patients undergoing cardiopulmonary bypass surgery. Patients were randomly assigned to a oxygen delivery strategy (maintaining a oxygen delivery index value >300 mL/min/m2 through pump flow adjustments during cardiopulmonary bypass) or a conventional strategy (a target pump flow was determined on the basis of the body surface area). The primary end point was the development of acute kidney injury. Secondary end points were the red blood cell transfusion rate and number of red blood cell units, intubation time, postoperative length of stay in the intensive care unit and the hospital, predischarge estimated glomerular filtration rate, and hospital mortality.ResultsAcute kidney injury occurred in 20 patients (14.6%) receiving the oxygen delivery strategy and in 42 patients (30.4%) receiving the conventional strategy (relative risk, 0.48; 95% confidence interval, 0.30-0.77; P = .002). The secondary end points were not significantly different between strategies. In a prespecified subgroup analysis of patients who had nadir hematocrit less than 23% or body surface area less than 1.40 m2, the oxygen delivery strategy seemed to be superior to the conventional strategy and the existence of quantitative interactions was suggested.ConclusionsAn oxygen delivery strategy for cardiopulmonary bypass management was superior to a conventional strategy with respect to preventing the development of acute kidney injury. 相似文献
45.
《HPB : the official journal of the International Hepato Pancreato Biliary Association》2022,24(10):1780-1788
BackgroundWe assessed whether or not covalently closed circular DNA (cccDNA) levels in the background liver influence the recurrence of hepatocellular carcinoma (HCC) in patients with resolved hepatitis B virus (HBV) infection.MethodsAmong 425 patients who underwent initial hepatectomy for HCC between 2010 and 2018, a retrospective review was performed in 44 with resolved HBV infection. The clinicopathologic characteristics were analyzed for correlation with tumor recurrence. The HBV cccDNA levels were tested via a droplet digital polymerase chain reaction assay.ResultsHBV cccDNA was detected in 27 of 44 patients (61%), and the median level was 1.0 copies/1000 ng (range, 0-931.3 copies/1000 ng). Anti-HBc ≥8.9 S/CO was associated with cccDNA detection (odds ratio, 11.08; 95% confidence interval [95% CI], 2.48-49.46; P = 0.002). Twenty-eight patients (64%) developed HCC recurrence after hepatectomy. The overall 3- and 5-year recurrence-free survival rates were 45.7% and 34.3%, respectively.19 HBV cccDNA levels was not significantly associated with HCC recurrence, while the presence of multiple tumors was an independent risk fact or (hazard ratio, 6.53; 95% CI, 2.48-17.19; P < 0.001.ConclusionHBV cccDNA levels did not influence HCC recurrence after hepatectomy. Anti-HBc levels may be used as a surrogate marker for cccDNA. 相似文献
46.
目的探究芒针深刺秩边穴对大鼠脊髓损伤后运动功能的影响及可能作用机制。方法选择健康雄性Wister大鼠81只,随机分为正常组、模型组和芒针组(正常组9只,其余两组各36只),采用改良Allen's造模法制备大鼠脊髓中度损伤模型,模型组不做特殊处理,芒针组采用芒针深刺秩边穴,每日1次,每次30 min。分别于术后1 d、3 d、5 d、7 d行BBB(Basso-Beattie-Bresnahan)运动功能评分;术后1 d、3 d、5 d、7 d取受损段脊髓组织行酶联免疫吸附测定(ELISA)、实时荧光定量PCR(RT-qPCR)和苏木素-伊红染色(HE染色)。结果术后5 d和7 d,芒针组大鼠BBB评分高于模型组,差异有统计学意义(P<0.01);脊髓损伤后,模型组和芒针组大鼠脊髓组织中高迁移率族蛋白B1(HMGB1)、核转录因子kB(NF-kB)、白介素-6(IL-6)含量及HMGB1mRNA、NF-kBmRNA、IL-6mRNA水平显著升高(P<0.05);受损的脊髓组织松散,灰质中有许多空洞形成,伴有炎性细胞浸润。芒针治疗后,芒针组大鼠脊髓组织中HMGB1、NF-kB、IL-6含量及HMGB1mRNA、NF-kBmRNA、IL-6mRNA水平较模型组降低,且在3 d、5 d、7 d差异有统计学意义(P<0.05);受损部位的空洞及炎性细胞逐渐减少。结论脊髓损伤后,炎症因子的大量聚集引起级联性炎症反应,影响大鼠运动功能的恢复。芒针的抗炎机制可能包括抑制HMGB1的表达,降低NF-kB信号通路的传导,下调促炎因子IL-6的分泌。 相似文献
47.
目的研究鸦胆子油软胶囊联合SOX方案(奥沙利铂+替吉奥)治疗晚期结直肠癌的临床疗效。方法选取2018年8月-2019年8月在郑州大学附属洛阳中心医院治疗的80例晚期结直肠癌患者,所有患者随机分为对照组和治疗组,每组各40例。对照组患者入院后给予SOX方案治疗,第1~14天给予注射用奥沙利铂,推荐剂量130 mg/m^2,溶于500 mL 5%葡萄糖溶液中,输注时间小于3h;第1~21天口服替吉奥胶囊,1粒/次,2次/d。治疗组在对照组基础上口服鸦胆子油软胶囊,4粒/次,3次/d。21 d为1个治疗疗程,两组患者接受治疗3个疗程。观察两组的临床疗效,比较Karnofsky(KPS)评分、生活质量(QOL)评分及血清癌胚抗原(CEA)、基质金属蛋白酶(MMP)-2和MMP-9水平。结果经过治疗后,治疗组客观缓解率(ORR)和疾病控制率(CBR)显著高于对照组(P<0.05)。治疗后,两组患者KPS评分和QOL评分显著升高(P<0.05),且治疗组KPS评分和QOL评分升高程度较大(P<0.05)。治疗后,两组CEA、MMP-2和MMP-9水平显著降低(P<0.05);并且治疗组降低较多(P<0.05)。治疗组胃肠道反应、血小板减少、白细胞减少和转氨酶升高等不良反应发生率明显低于对照组(P<0.05)。结论鸦胆子油软胶囊联合SOX方案治疗晚期结直肠癌具有较好的治疗效果,能够提高患者生活质量,降低肿瘤标志物水平,安全性较高,值得在临床上推广应用。 相似文献
48.
目的探讨不同程度碘对比剂后急性肾损伤的危险因素及其转归预后。方法筛选2016年4月1日至2019年8月31日于重庆医科大学附属第三医院住院期间发生碘对比剂后急性肾损伤(PC-AKI)的患者,按照急性肾损伤分层标准将其分为非严重损伤组(A组)和严重损伤组(B组),从基本人口学资料、基础疾病、药物使用情况、转归预后等方面分析两组患者的特点及差异。结果 1 920例患者中发生PC-AKI者90例,其中A组72例(80.00%),B组18例(20.00%),B组中最终需肾脏替代治疗(血液透析)干预者11例(12.22%)。A组与B组间一般情况、基础肾功能、碘对比剂的使用以及联用肾毒性药物、静脉水化量等观察指标无统计学差异。B组合并慢性疾病者更多,其中冠心病(55.56%vs 29.17%)、心肌梗死(27.78%vs 5.56%)患病率差异具有统计学意义(P<0.05),行血液透析的患者第一诊断为心肌梗死者占45.45%。65.85%的患者在使用对比剂后10 d内肌酐仍高于基线,54.54%的透析患者在出院时仍需透析治疗,81.81%的透析患者出院时死亡或放弃治疗。结论合并冠心病、心肌梗死的患者更容易发生严重PC-AKI,当合并这些疾病的患者使用碘对比剂时,临床医师应密切关注其肾功能的变化。PC-AKI的肾功转归较差,发生PC-AKI后需透析治疗的患者往往预后不良。 相似文献
49.
《慢性疾病与转化医学(英文)》2020,6(2):98-105
Coronavirus disease 2019 is a major threat to public health globally. Though its pathogenesis has not been fully elucidated, angiotensin-converting enzyme 2 (ACE2) has been recently identified as a receptor for the entry of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the cell. Here, we aimed to clarify the potential role of ACE2 in SARS-CoV-2-induced acute lung injury and its underlying mechanism. As a receptor for coronavirus, ACE2 mediates the entry of SARS-CoV-2 into cells in a similar way as for severe acute respiratory syndrome coronavirus (SARS-CoV). The high binding affinity of SARS-CoV-2 to ACE2 correlates with its efficient spread among humans. On the other hand, ACE2 negatively regulates the renin-angiotensin-aldosterone system (RAAS) primarily by converting angiotensin II to angiotensin 1–7, which exerts a beneficial effect on coronavirus-induced acute lung injury. Human recombinant ACE2 has been considered as a potential therapy for SARS-CoV-2 by blocking virus entry and redressing the imbalance of RAAS in SARS-CoV-2 infection. The level of ACE2 expression can be upregulated by treatment with an ACE inhibitor (ACEI) or angiotensin Ⅱ type 1 receptor blocker (ARB). To date, no evidence shows that ACEIs or ARBs increase the susceptibility and mortality of patients infected with SARS-CoV-2, and hence, it is not advisable to discontinue such drugs in patients with cardiovascular disease. 相似文献
50.
放射性肺损伤是胸部肿瘤放疗后常见并发症,随着对放射性肺炎研究不断深入,如何为基础研究和药物干预寻求最佳的动物模型和效应评价已成为当前亟待解决的难题之一。通过检索近10年文献,对不同放射性肺损伤模型动物及放射部位的选择、照射剂量的确定、照射方法的比较和动物模型效应评价进行了对比研究,以期寻找建立放射性肺损伤动物模型的稳定方法和较为明确的效应机制,为防护和减缓放射性肺损伤的发生发展而进行的基础研究和药物研制提供可靠的方法。 相似文献