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41.
目的 探讨改良单图像法手工测量髌骨不稳患者胫骨结节-股骨滑车沟(tibial tuberosity-trochlear groove,TT-TG)间距的可行性。
方法 选取髌骨不稳患者30例。高年资手术医师A、B,使用改良单图像法手工测量髌骨不稳患者TT-TG间距,对比高资年影像学医师C,使用双图法测量髌骨不稳患者TT-TG间距。应用Cronbach′s alpha系数评价结果的可信度。应用组内相关系数(intraclass correlation coefficient,ICC)评价结果的可重复性。使用Bland-Altman分析图评价结果的一致性。
结果 高年资手术医师A、B使用改良单图像法手工测量髌骨不稳患者TT-TG间距分别和高年资影像学医师C使用双图法测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数分别为0.913和0.959,组内相关系数分别为0.913和0.958。Bland-Altman分析图显示,TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)和0.143(95%CI:-3.110~3.397)。A、B医师之间使用改良单图像法手工测量髌骨不稳患者TT-TG间距比较,Cronbach′s alpha系数为0.891,组内相关系数为0.891。Bland-Altman分析图显示TT-TG间距差值(mm)的均值为-0.276(95%CI:-3.526~2.974)。
结论 改良单图像法手工测量髌骨不稳患者TT-TG间距操作简单,可以准确测量出髌骨不稳患者的TT-TG间距,该方法和双图法可以相互替换使用。 相似文献
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The significance of hepatobiliary scintigraphy (HBS) for hepatic graft function assessment was established mostly on retrospective studies and was not widely recognized due to the lack of quantitative data and variation in accuracy. This prospective study was performed to investigate the effectiveness of quantitative HBS for assessing hepatocyte dysfunction and biliary complication in liver transplant recipients.In 57 recipients who had undergone orthotopic liver transplantation, a total of 67 dynamic 99mTc-EHIDA scans were performed and quantitative parameters including the hepatocyte extraction fraction (HEF), time to maximum hepatic radioactivity (Tmax), and time for peak activity to decrease by 50% (T1/2) were calculated. The scintigraphic results based on the 3 parameters were compared against the final diagnosis. A ROC curve analysis was carried out to identify the cutoff value of Tmax for diagnosis of biliary stricture. Correlation between the parameters of postoperative HBS and conventional biochemical liver function indices were also analyzed.Quantitative 99mTc-EHIDA HBS had an overall sensitivity of 94.12% (16/17), specificity of 93.33% (42/45), and diagnostic accuracy of 93.55% (58/62) for detecting hepatocyte dysfunction and biliary complication in liver transplant recipients. The recommended cutoff value of Tmax for diagnosis of post-transplant biliary stricture was set at 15.75 min with a sensitivity of 100.0% and a specificity of 94.0%. The scintigraphic parameters (HEF, Tmax) were statistically significantly associated with the conventional liver function parameters.Quantitative 99mTc-EHIDA HBS offers a noninvasive imaging modality with high sensitivity and specificity to diagnose hepatocyte dysfunction as well as distinguish between patients with or without biliary stricture following liver transplantation. Furthermore, HEF and Tmax values obtained from dynamic HBS show good correlation with conventional liver function parameters. 相似文献
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Learning to Discretize: Solving 1D Scalar Conservation Laws via Deep Reinforcement Learning
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Yufei Wang Ziju Shen Zichao Long & Bin Dong 《Communications In Computational Physics》2020,28(5):2158-2179
Conservation laws are considered to be fundamental laws of nature. It has
broad applications in many fields, including physics, chemistry, biology, geology, and
engineering. Solving the differential equations associated with conservation laws is a
major branch in computational mathematics. The recent success of machine learning,
especially deep learning in areas such as computer vision and natural language processing, has attracted a lot of attention from the community of computational mathematics and inspired many intriguing works in combining machine learning with traditional methods. In this paper, we are the first to view numerical PDE solvers as an
MDP and to use (deep) RL to learn new solvers. As proof of concept, we focus on
1-dimensional scalar conservation laws. We deploy the machinery of deep reinforcement learning to train a policy network that can decide on how the numerical solutions should be approximated in a sequential and spatial-temporal adaptive manner.
We will show that the problem of solving conservation laws can be naturally viewed
as a sequential decision-making process, and the numerical schemes learned in such a
way can easily enforce long-term accuracy. Furthermore, the learned policy network
is carefully designed to determine a good local discrete approximation based on the
current state of the solution, which essentially makes the proposed method a meta-learning approach. In other words, the proposed method is capable of learning how to
discretize for a given situation mimicking human experts. Finally, we will provide details on how the policy network is trained, how well it performs compared with some
state-of-the-art numerical solvers such as WENO schemes, and supervised learning
based approach L3D and PINN, and how well it generalizes. 相似文献
47.
Wen Wang Yanmei Liu Chuan Yu Jing Tan Weiyi Xiong Duo Dong 《Expert opinion on drug safety》2020,19(3):339-347
ABSTRACTObjectives: Limited evidence has suggested that cefoperazone-sulbactam causes coagulation disorders and bleeding.Methods: The authors conducted a retrospective study to compare patients receiving cefoperazone-sulbactam versus those treated with cefoperazone-tazobactam or ceftazidime. Propensity-score matching was used to explore whether treatment with cefoperazone-sulbactam increased the risk of prothrombin time (PT) prolongation, coagulation disorders, and bleeding, or decreased platelets (PLT).Results: The cohort included 23,242 patients. Among patients receiving cefoperazone-sulbactam, the risk of PT prolongation, coagulation disorders, decreased PLT, and bleeding was 5.3%, 9.2%, 15.7%, and 4.2%, respectively. Propensity-score matching analyses suggested that cefoperazone-sulbactam increased the risk of PT prolongation (aOR 2.26, 95% CI 1.61–3.18), coagulation disorders (aOR 1.81, 95% CI 1.43–2.30), and decreased PLT (aOR 1.46, 95% CI 1.25–1.72), but not increase bleeding (aOR 1.05, 95% CI 0.79–1.40) compared with ceftazidime. Patients receiving cefoperazone-sulbactam had higher risk of PT prolongation (aOR 1.53, 95% CI 1.11–2.10), coagulation disorders (aOR 1.53, 95% CI 1.21–1.95), but not decreased PLT (aOR 0.93, 95% CI 0.81–1.07) or bleeding (aOR 1.11, 95% CI 0.87–1.42), compared with those receiving cefoperazone-tazobactam.Conclusion: Cefoperazone-sulbactam may be associated with a higher risk of PT prolongation and coagulation disorders compared with cefoperazone-tazobactam and ceftazidime. 相似文献
48.
目的 制备具有天然神经组织结构的支架,构建组织工程化面神经用于修复面神经损伤。方法 取家兔面神经,改良化学萃取法制备脱细胞神经基质,HE染色形态学观察去细胞及脱髓鞘情况,荧光分光光度计测定支架内细胞经Quant-iT PicoGreen工作液染色后的DNA含量。MTT法检测细胞在支架上的相对生长率从而检测支架的细胞毒性。结果 支架移植体呈圆柱形,弹性与正常神经基本一致,组织观察显示细胞结构未见残余完整细胞及细胞碎片残留,未见神经髓鞘及轴突结构,细胞外基质形成纵向排列结构,结构之间可见空隙。兔脱细胞面神经基质支架内残留的DNA含量较正常兔面神经明显下降(P<0.01)。神经基质供体无细胞毒性。结论 改良化学萃取法可有效去除面神经细胞,天然结构保存完好,细胞毒性低,可作为组织工程化面神经的支架。 相似文献
49.
目的探讨化浊解毒方治疗溃疡性结肠炎(UC)的治疗作用及机制。方法120例UC患者按照随机数字表法分为观察组、对照组各60例。观察组予中药化浊解毒方口服,每日1剂,早晚2次温服;对照组予美沙拉嗪肠溶片口服,1.0 g/次,3次/d。2组疗程均4周。对比2组治疗前后Geboes指数、结肠镜下黏膜表现、生活质量评分、疾病活动指数及血清炎性因子IL-8、IL-35水平,凝血指标血清FIB水平,统计治疗后1年内复发情况。结果治疗后,观察组Geboes指数、疾病活动指数及血清炎性因子IL-8水平、凝血指标血清FIB水平均较本组治疗前降低,生活质量评分、血清炎性因子IL-35水平升高(P<0.05);且观察组治疗后疾病活动指数及血清炎性因子IL-8水平、凝血指标血清FIB水平均低于对照组,生活质量评分、血清炎性因子IL-35水平均高于对照组(P<0.05)。与对照组相比,治疗组糜烂、溃疡改善不明显(P>0.05),充血水肿、颗粒样变等肠镜表现改善情况均优于对照组(P<0.05)。治疗结束1年观察组复发率为10.64%,对照组为23.53%,2组差异有统计学意义(P<0.05)。结论化浊解毒方能改善UC患者临床症状,修复肠黏膜病理损伤,降低复发率;其机制可能与调节血清炎性因子IL-8、IL-35和凝血因子FIB水平有关。 相似文献
50.
Ye Gao Lei Xin Yu-Xin Wang Yuan-Hang Dong Zhuan Liao 《Scandinavian journal of gastroenterology》2020,55(1):105-113
AbstractBackground and aim: Capsule retention is the most common adverse event associated with video capsule endoscopy. The use of double-balloon enteroscopy-assisted capsule endoscope retrieval has been increasingly reported in recent years. However, evidence is limited regarding its success rate, associated factors, and subsequent clinical outcomes.Methods: A systematic review of relevant studies published before January 2019 was performed. Successful retrieval rate and associated factors, rate of endoscopic balloon dilation, and outcomes after double-balloon enteroscopy were summarized and pooled.Results: Within 154 associated original articles, 12 including 150 cases of capsule retrieval by double-balloon enteroscopy were included. The estimated pooled successful retrieval rate was 86.5% (95% confidence interval, 75.6–95.1%). Anterograde approach and capsules retained in the jejunum or trapped by malignant strictures were associated with a higher successful retrieval rate than the retrograde approach (62/83 [74.7%] vs. 10/38 [26.3%], p?<?.001) and capsules retained in the ileum (41/41 [100.0%] vs. 43/58 [74.1%], p?<?.001) or trapped by benign strictures (21/21 [100.0%] vs. 65/83 [78.3%], p?=?.043). Endoscopic balloon dilation was performed in 38.8% (95% confidence interval, 22.3–56.3%) of patients with benign strictures. Two perforations (1.3%) were reported as severe adverse events after double-balloon enteroscopy. A significantly lower surgery rate was found among cases with successful video capsule removal compared with unsuccessful cases (7.2% vs. 38.5%, p?=?.002).Conclusions: Double-balloon enteroscopy is feasible and safe for removing retained video capsule endoscopes, and its use could decrease the need for surgery in patients with benign strictures and facilitate subsequent surgery in patients with malignant strictures. 相似文献