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991.
目的研究结直肠癌人工智能病理诊断模型构建过程中,病理医师对数字切片癌组织的人工标注在不同扫描仪构建的全切片图像(WSI)中准确迁移的方法。
方法在本研究中,我们提出了一种基于图像配准的标注迁移方法,在来自不同扫描仪的WSI之间建立仿射映射。通过多分辨率最小化两个WSI缩略图之间的互信息来估计最佳仿射映射参数,以避免和改变扫描仪特定特性的影响,减少计算时间。我们使用了181张结直肠癌病理切片,使用两个品牌的扫描仪获得相应的WSI,对上述标注迁移方法进行测试。
结果181张HE切片的扫描结果表明,同一张切片由不同扫描仪构建的WSI在颜色、位置、大小等属性上都有不同的表现。使用我们提出的标注迁移方法,其中179张图像的人工标注成功地在不同扫描仪构建的WSI中迁移,其中125对使用单个CPU核心的计算时间不到1分钟。
结论我们提出了一种快速、准确的全自动的标注迁移方法,用于在不同扫描仪构建的WSI之间传递人工标注。在准备深度学习训练数据过程中,既可以避免病理医师对新图像的重新标注,也可以避免病理医师之间在标注上的差异。 相似文献
992.
目的:探讨经皮颈内静脉长期导管在老年维持性血液透析患者中的应用及其常见并发症的防治。方法对2009年12月至2012年12月在中南大学湘雅医院行经皮颈内静脉长期置管的15例维持性血液透析老年患者的临床资料进行回顾性分析,观察置管术后情况、导管的使用情况、常见并发症的防治、透析充分性评价等。结果(1)实施颈内静脉长期置管18例次,其中3例为重新置管,置管成功率100%。(2)导管相关并发症:2例患者术后1周内出现置管处局部渗血;1例出现导管出口感染,2例发生导管相关性血流感染;3例患者出现导管血栓形成;2例诊断导管纤维鞘形成;1例因人为损坏出现导管破裂。经过相应处理后均使问题得到解决。(3)导管使用期限:本组患者长期导管使用时间为4~41个月,除1例死亡(原因为脑出血),3例为重新置管,余患者仍继续使用。(4)透析充分性评价:15例患者平均尿素下降率为72%,平均尿素清除指数达1.54。结论对于血管条件差无法建立动静脉内瘘的老年血透患者,使用颈内静脉长期导管行血液透析可以达到充分透析;提高置管及导管护理技术、加强健康宣教,能延长导管使用年限,减少导管并发症。 相似文献
993.
Nontumoral portal vein thrombosis (PVT) is an increasingly recognized complication in patients with cirrhosis. Substantial evidence shows that portal flow stasis, complex thrombophilic disorders, and exogenous factors leading to endothelial dysfunction have emerged as key factors in the pathogenesis of PVT. The contribution of PVT to hepatic decompensation and mortality in cirrhosis is debatable; however, the presence of an advanced PVT increases operative complexity and decreases survival after transplantation. The therapeutic decision for PVT is often determined by the duration and extent of thrombosis, the presence of symptoms, and liver transplant eligibility. Evidence from several cohorts has demonstrated that anticoagulation treatment with vitamin K antagonist or low molecular weight heparin can achieve recanalization of the portal vein, which is associated with a reduction in portal hypertension-related events and improved survival in cirrhotic patients with PVT. Consequently, interest in direct oral anticoagulants for PVT is increasing, but clinical data in cirrhosis are limited. Although the most feared consequence of anticoagulation is bleeding, most studies indicate that anticoagulation therapy for PVT in cirrhosis appears relatively safe. Interestingly, the data showed that transjugular intrahepatic portosystemic shunt represents an effective adjunctive therapy for PVT in cirrhotic patients with symptomatic portal hypertension if anticoagulation is ineffective. Insufficient evidence regarding the optimal timing, modality, and duration of therapy makes nontumoral PVT a challenging consequence of cirrhosis. In this review, we summarize the current literature and provide a potential algorithm for the management of PVT in patients with cirrhosis. 相似文献
994.
995.
Irina Girleanu Carol Stanciu Camelia Cojocariu Lucian Boiculese Ana-Maria Singeap Anca Trifan 《Saudi Journal Of Gastroenterology》2014,20(5):288-292
Background/Aim:
Portal vein thrombosis (PVT) has a high incidence in patients with liver cirrhosis and determines a poor prognosis of hepatic disease. The aim of our study was to define the natural course of partial PVT in cirrhotic patients, including survival and decompensation rates.Patients and Methods:
We performed a prospective, cohort study, in a tertiary referral center. There were 22 cirrhotic patients with partial nonmalignant PVT, without anticoagulant treatment, who were followed-up between January 2011 and October 2013. All patients were evaluated by Doppler abdominal ultrasound and computed tomography. Kaplan–Meier method was used to determine the difference in clinical events between the study subgroups.Results:
After a mean follow-up period of 20.22 months, partial PVT improved in 5 (22.73%), was stable in 11 (50%), and worsened in 6 (27.27%) patients. Hepatic decompensation rate at 6 and 18 months was higher in patients with worsened PVT than in those with stable/improved PVT (50% vs. 25%, P < 0.0001 and 100% vs. 56.25%, P < 0.0001, respectively). The survival rate at 6 months was 66.66% in worsened PVT group vs. 81.25% (P = 0.005) in stable/improved group, and 16.66% vs. 81.25% (P < 0.0001) at 18 months, respectively. Multivariate analysis showed that Model of End-Life Disease was the independent predictor of hepatic decompensation [hazard ratio (HR) 1.42; 95% confidence interval (CI): 1.08−1.87, P = 0.012] and survival (HR 1.76; 95% CI: 1.06−2.92, P = 0.028).Conclusions:
Nonmalignant partial PVT remained stable/improved in over half of cirrhotic patients and aggravated in more than one fourth in whom it negatively influenced the survival and decompensation rates. 相似文献996.
目的比较达比加群酯与华法林治疗脑静脉血栓形成(cerebral venous thrombosis,CVT)安全性和有效性。方法回顾性分析2017年1月至2018年12月在河南省人民医院神经内科住院治疗的CVT患者的病历资料,根据用药情况分为达比加群酯组和华法林组。主要转归指标为治疗后6个月时的功能转归良好,定义为改良Rankin量表评分0~2分。次要转归指标包括受累静脉窦再通率以及出血发生率。结果共纳入152例CVT患者,其中达比加群酯组34例,华法林组118例。两组人口统计学和基线资料比较均差异无统计学意义。治疗6个月时,达比加群酯组和华法林组功能转归良好率(94.1%对93.2%;χ^2=0.043,P=0.836)以及受累静脉窦再通率(94.1%对93.2%;χ^2=0.043,P=0.836)均差异无统计学意义。达比加群酯组出血发生率显著低于华法林组(8.8%对27.1%;χ^2=4.985,P=0.026),两组轻微出血发生率差异无统计学意义(8.8%对16.1%;χ^2=0.618,P=0.432),但达比加群酯组严重出血发生率有显著低于华法林组的趋势(0%对11.0%;Fisher精确检验P=0.074)。达比加群酯组无死亡病例,华法林组死亡2例,其中1例妊娠期女性患者在治疗4个月时死于CVT复发,1例男性患者在治疗2个月时死于急性心肌梗死。两组病死率差异无统计学意义(0%对1.7%;Fisher精确检验P=1.000)。结论达比加群酯治疗CVT的有效性不逊于华法林,且出血并发症风险更低。 相似文献
997.
998.
Ashish Aggarwal Kanika Puri Suthat Liangpunsakul 《World journal of gastroenterology : WJG》2014,20(19):5737-5745
Patients with liver cirrhosis were traditionally believed to be protected against development of blood clots.Lately,studies have shown that these patients may probably be at an increased risk of venous thrombotic complications.Although the hemostatic changes in the chronic liver disease patients and the factors that may predict bleeding vs thrombotic complications remains an area of active research,it is believed that the coagulation cascade is delicately balanced in these patients because of parallel reduced hepatic synthesis of pro and anticoagulant factors.Thrombotic state in cirrhotic patients is responsible for not only portal or non-portal thrombosis[deep vein thrombosis(DVT)and pulmonary embolism(PE)];it has also been associated with progression of liver fibrosis.The use of anticoagulants in cirrhosis patients is a challenging,and often a scary situation.This review summarizes the current literature on the prevalence of venous thrombosis(DVT and PE),risk factors and safety of prophylactic and therapeutic anticoagulation in patients with chronic liver disease. 相似文献
999.
Gurpreet Singh Dhillon Shohreh Honarbakhsh Antonio Di Monaco Ann Elizabeth Coling Kernerov Lenka Francesca Pizzamiglio Ross J. Hunter Rodney Horton Moussa Mansour Andrea Natale Vivek Reddy Massimo Grimaldi Petr Neuzil Claudio Tondo Richard J. Schilling 《Journal of cardiovascular electrophysiology》2020,31(6):1259-1269