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采用Mimics对心脏进行三维重构,用3-matic进行模型优化以及模型误差分析,对左心室室壁运动做速度分布假设,基于UDF宏文件对左心室室壁运动编写程序,将血液视为非牛顿流体,采用动网格技术研究不同血压对左心室血液流动的影响。模拟发现当左心室收缩时,压力梯度明显,内部压力减小。当左心室舒张时,内部压力逐渐增高。二尖瓣口处的速率先增大后减小。血压升高,左心室内剪切应力持续增大,极易破坏红细胞结构,产生溶血现象,导致心脏功能紊乱。  相似文献   
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Objective: To observe the effects and safety of Tongyan Spray (通咽喷雾剂) on the range and time of hyoid motion in patients with ischemic post-stroke dysphagia. Methods: Seventy-two patients with ischemic post-stroke dysphagia were selected and randomly assigned to a treatment group (36 cases) and a control group (36 cases) by a random number table from January 2013 to October 2014. All patients swallowed 4 kinds of barium meals with different traits respectively, and each patient underwent video fluoroscopy (VF) examination twice. In the treatment group, Tongyan Spray was sprayed to the pharynx on both sides and the middle part once respectively. The spray was applied 30 min before the second examination. Purified water at room temperature was used as placebo in the control group. The changes in the range and time of hyoid motion in both groups were observed before and after treatment. Results: Six patients dropped out in each group, and 60 patients completed the study and were included in the final analysis. Significant improvement was observed in the range of superior hyoid excursion distance and the time of hyoid motion in the treatment group compared with the control group (P<0.05). There were no obvious adverse reactions observed in oral mucosa in both groups during the whole study. Conclusion: Tongyan Spray was an effective and safe medicine for improving swallowing function in patients with ischemic post-stroke dysphagia.  相似文献   
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Objective: To study the effect and mechanism of Huayu Wan (化瘀丸, HYW) in combination of chemotherapy of tumor treatment. Methods: HYW serum was added in Lewis cells to assess its impact on fluorescent doxorubicin delivery in vitro. Then, Lewis tumor cells was implanted in C57BL/6 mice via xenograft transplantation. Tumor growth was measured and signal intensity corresponding to blood flow was assessed by laser doppler perfusion imaging (LDPI). Finally, the effect of HYW on the efficacy of doxorubicin was studied. Results: HYW can improve the transfer of fluorescent doxorubicin into cells. The blood flow signal in the tumor tissues of the HYW group was higher than that of the control group (P<0.01). Furthermore, HYW improved drug delivery of doxorubicin to tumor tissues, and this activity was associated with HYW-induced microvascular proliferation (P<0.01). Conclusions: HYW can promote microangiogenesis and increase blood supply in tumor tissues, which in turn may increase the risk of metastasis. At the same time, HYW increases drug delivery and improves the efficacy of chemotherapy drugs through vascular proliferation. Therefore, rational judgment must be exercised when considering applying HYW to an antitumor regimen.  相似文献   
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目的 探讨血清高迁移率族蛋白B1(HMGBl)、可溶性髓样细胞触发受体样转录因子-1(sTLT-1)水平与脓毒症患者急性肺损伤(ALI)的关系.方法 选取脓毒症患者160例为研究对象,根据住院期间是否出现ALI分为ALl组(47例)和非ALI组(113例).收集患者一般资料,采用酶联免疫吸附法检测血清HMGB1、sTLT-1水平.采用Pearson法分析脓毒症ALI患者血清HMGB1、sTLT-1水平与相关指标的关系,采用多因素Logistic回归分析观察探讨脓毒症ALI的危险因素,采用受试者工作特征曲线(ROC)分析观察HMGB1、sTLT-1水平对脓毒症患者发生ALI的预测价值.结果 ALI组氧合指数[pa(O2)/FiO2]低于非ALI组,序贯器官衰竭(SOFA)评分、C反应蛋白(CRP)、N-端脑利钠肽前体(NT-proBNP)及血清HMGB1、sTLT-1水平均高于非ALI组,差异有统计学意义(P<0.05).脓毒症ALI患者血清HMGB1、sTLT-1水平与pa(O2)/FiO2呈负相关,与SOFA评分、CRP、NT-proBNP呈正相关(P<0.05).pa(O2)/FiO2、SOFA评分及血清HMGB1、sTLT-1水平均是影响脓毒症ALI发生的危险因素(P<0.05).血清HMGB1、sTLT-1水平联合预测脓毒症患者发生ALI的曲线下面积为0.910,联合预测的敏感度和特异度高于血清HMGB1、sTLT-1水平单独预测.结论 脓毒症ALl患者血清HMGB1、sTLT-1水平升高,可作为判断ALI发生的潜在血清指标.  相似文献   
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BackgroundTo introduce and determine the value of optimized strategies for the management of urological tube-related emergencies with increased incidence, complexity and operational risk during the global spread of coronavirus disease 2019 (COVID-19).MethodsAll emergent urological patients at Tongji Hospital, Wuhan, during the period of January 23 (the beginning of lockdown in Wuhan) to March 23, 2020, and the corresponding period in 2019 were recruited to form this study’s COVID-19 group and control group, respectively. Tongji Hospital has the most concentrated and strongest Chinese medical teams to treat the largest number of severe COVID-19 patients. Patients in the control group were routinely treated, while patients in the COVID-19 group were managed following the optimized principles and strategies. The case incidence for each type of tube-related emergency was recorded. Baseline characteristics and management outcomes (surgery time, secondary complex operation rate, readmission rate, COVID-19 infection rate) were analyzed and compared across the control and COVID-19 periods.ResultsThe total emergent urological patients during the COVID-19 period was 42, whereas during the control period, it was 124. The incidence of tube-related emergencies increased from 53% to 88% (P<0.001) during the COVID-19 period. In particular, the incidence of nephrostomy tube-related (31% vs. 15%, P=0.027) and single-J stent-related problems (19% vs. 6%, P=0.009) increased significantly. The mean surgery times across the two periods were comparable. The number of secondary complex operations increased from 12 (18%) to 14 (38%) (P=0.028) during the COVID 19-period. The number of 2-week postoperative readmission decreased from 10 (15%) to 1 (3%) (P=0.049). No participants contracted during the COVID-19 period.ConclusionsUrological tube-related emergencies have been found to have a higher incidence and require more complicated and dangerous operations during the COVID-19 pandemic. However, the optimized management strategies introduced in this study are efficient, and safe for both urologists and patients.  相似文献   
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肝细胞癌(HCC)是最常见的恶性肿瘤之一。尽管在早期诊断和个体化治疗方面取得了进展,但经根治性切除等治疗后,HCC患者的临床预后仍不佳,复发率高。因此,在HCC患者中识别准确可靠的预后标志物是必要的。作为一种新的免疫营养生物标志物,控制营养状态(CONUT)评分已被报道用于预测癌症患者的预后。本文将对术前CONUT评分与HCC肝切除术后预后的研究进展进行综述。  相似文献   
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组织工程技术通过利用支架材料、种子细胞、生长因子以达到修复或再生组织器官的目的。支架材料的作用是为种子细胞提供机械支撑并且保护细胞免受体内有害微环境的影响。因此,选择或制备适当的支架材料是组织工程中的关键一步。近年来,将支架材料和牙龈间充质干细胞(gingival mesenchymal stem cells,GMSCs)联合应用于组织工程的研究逐渐走向成熟。本文就组织工程中牙龈间充质干细胞递送支架载体的研究现状进行综述,以期为GMSCs组织工程递送支架载体材料的开发和选择提供思路。  相似文献   
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