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1.
In this paper, effective Eulerian algorithms are introduced for the computation of the forward finite time Lyapunov exponent (FTLE) of smooth flow fields. The advantages of the proposed algorithms mainly manifest in two aspects. First, previous Eulerian approaches for computing the FTLE field are improved so that the Jacobian of the flow map can be obtained by directly solving a corresponding system of partial differential equations, rather than by implementing certain finite difference upon the flow map, which can significantly improve the accuracy of the numerical solution especially near the FTLE ridges. Second, in the proposed algorithms, all computations are done on the fly, that is, all required partial differential equations are solved forward in time, which is practically more natural. The new algorithms still maintain the optimal computational complexity as well as the second order accuracy. Numerical examples demonstrate the effectiveness of the proposed algorithms.  相似文献   
2.
韦斌  连浩  邓彦  孙园园 《国际眼科杂志》2022,22(12):1960-1964

目的:评估飞秒激光辅助超声乳化联合Ahmed青光眼引流阀植入术治疗合并难治性青光眼的白内障的有效性和安全性。

方法:回顾性病例对照研究。2019-10/2021-10入院合并难治性青光眼的白内障患者53例53眼,依据自愿选择分为飞秒激光辅助白内障超声乳化(FLACS)组26例26眼和常规白内障超声乳化(CPCS)组27例27眼。两组分别行FLACS和CPCS联合Ahmed青光眼引流阀植入术。比较两组患者术中超声乳化能量释放量(CDE)、有效超声时间(EPT)的差异和术前与术后抗青光眼药物数量的变化,以及术后观察不同时期(1d,1wk,1、3mo)在提高最佳矫正视力(BCVA),降低眼压、角膜内皮细胞损伤程度和手术并发症及成功率状况。

结果:FLACS组术中CDE和EPT明显低于CPCS组(t=8.50、5.16; P<0.01、=0.001)。两组术后抗青光眼药物较术前均明显减少(t=9.12、7.76; P=0.011、0.016),但两组间无差异(t=1.79,P=0.082)。两组术后BCVA均较术前改善,眼压均较术前降低(P<0.05)。FLACS组在术后早期(1d,1wk)BCVA的改善较CPCS组更显著(t=9.74、8.49; P=0.008、0.012),但在术后1、3mo的BCVA改善程度并无不同(t=0.62、0.44; P=1.415、2.021)。CPCS组在术后随访不同时期的角膜内皮细胞损伤较FLACS组更明显(P<0.05)。术后随访的不同时期FLACS组和CPCS组在控制眼压方面无差异(F组间=0.64,P组间=0.421)。FLACS组的手术并发症发生率27%(7/26)较CPCS组89%(24/27)低(χ2=20.95,P<0.01),其中角膜水肿(8% vs 41%)、前囊撕裂(0 vs 11%)在FLACS组中明显低于CPCS组,后囊破裂(0 vs 7%)、玻璃体脱出(0 vs 4%)及人工晶状体偏位(0 vs 7%)也均发生在CPCS组。但两组的治疗总成功率相近(P=28.718)。

结论:飞秒激光辅助超声乳化联合Ahmed青光眼引流阀植入术可充分发挥联合手术的精准微创可控优势,帮助合并难治性青光眼的白内障患者有效降低眼压及更早获得视力恢复。  相似文献   

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目的分析虹膜角膜内皮(ICE)综合征患者的临床特征。方法回顾性病例系列研究。收集2014年1月至2020年5月在温州医科大学附属眼视光医院诊断为ICE综合征患者的临床资料。记录患者的临床类型、生活视力、临床特征及继发性青光眼情况。采用广义估计方程中的Wald χ2检验等方法对3种临床类型的临床特征进行比较。结果共纳入114例(127只眼)ICE综合征患者, 其中女性64例, 男性50例;就诊年龄为(49±13)岁。Chandler综合征(CS)53例(46.5%), 进行性虹膜萎缩(PIA)36例(31.6%), Cogan-Reese综合征(CRS)24例(21.0%), 无法明确临床类型1例(0.9%)。101例(88.6%)患者为单眼发病。在CS、PIA及CRS中分别有81.7%(49/60)、56.1%(23/41)及41.7%(10/24)患眼的生活视力低于0.3;角膜水肿在CS中最多见(52.5%, 32/61), 其次是PIA(29.3%, 12/41)以及CRS(20.8%, 5/24);瞳孔异位在CS、PIA、CRS中分别占78.7%(48/61)、95.1%(39/...  相似文献   
6.
Zedoary tumeric (Curcumae Rhizoma, Ezhu in Chinese) has a long history of application and has great potential in the treatment of liver cancer. The anti liver cancer effect of zedoary tumeric depends on the combined action of multiple pharmacodynamic substances. In order to clarify the specific mechanism of zedoary tumeric against liver cancer, this paper first analyzes the mechanism of its single pharmacodynamic substance against liver cancer, and then verifies the joint anti liver cancer mechanism of its "pharmacodynamic group". By searching the research on the anti hepatoma effect of active components of zedoary tumeric in recent years, we found that pharmacodynamic substances, including curcumol, zedoarondiol, curcumenol, curzerenone, curdione, curcumin, germacrone, β-elemene, can act on multi-target and multi-channel to play an anti hepatoma role. For example, curcumin can regulate miR, GLO1, CD133, VEGF, YAP, LIN28B, GPR81, HCAR-1, P53 and PI3K/Akt/mTOR, HSP70/TLR4 and NF-κB. Wnt/TGF/EMT, Nrf2/Keap1, JAK/STAT and other pathways play an anti hepatoma role. Network pharmacological analysis showed that the core targets of the "pharmacodynamic group" for anti-life cancer are AKT1, EGFR, MAPK8, etc, and the core pathways are neuroactive live receiver interaction, nitrogen metabolism, HIF-1 signaling pathway, etc. At the same time, by comparing and analyzing the relationship between the specific mechanisms of pharmacodynamic substance and "pharmacodynamic group", it is found that they have great reference significance in target, pathway, biological function, determination of core pharmacodynamic components, formation of core target protein interaction, in-depth research of single pharmacodynamic substance, increasing curative effect and so on. By analyzing the internal mechanism of zedoary tumeric pharmacodynamic substance and "pharmacodynamic group" in the treatment of liver cancer, this paper intends to provide some ideas and references for the deeper pharmacological research of zedoary tumeric and the relationship between pharmacodynamic substance and "pharmacodynamic group".  相似文献   
7.
This phase II randomized clinical trial aimed to assess the efficacy and toxicity of Endostar, an antiangiogenesis inhibitor, combined with concurrent chemoradiotherapy (CCRT) for locally advanced cervical cancer (LACC). Patients with LACC were randomly assigned to either CCRT plus Endostar (CCRT+E arm) or CCRT alone (CCRT arm). All patients received pelvic intensity-modulated radiation therapy (IMRT) and brachytherapy. Weekly cisplatin was administered concurrently with IMRT. Patients in the CCRT+E arm also received concurrent Endostar every 3 weeks for two cycles. The primary endpoint was progression-free survival (PFS) and acute toxicities. The exploratory endpoint was the impact of vascular endothelial growth factor receptor-2 (VEGFR2) expression on long-term survival. A total of 116 patients were enrolled. Patients in the CCRT+E arm and in the CCRT arm had similar acute and late toxicity profile. The 1- and 2-year PFS were 91.4% versus 82.1% and 80.8% versus 63.5% (p=0.091), respectively. The 1- and 2-year distance metastasis-free survival (DMFS) were 92.7% versus 81.1% and 86.0% versus 65.1% (p=0.031), respectively. Patients with positive VEGFR2 expression had significant longer PFS and overall survival (OS) compared with those with negative VEGFR2 expression. Patients in the CCRT+E arm had significantly longer PFS, OS, and DMFS than those in the CCRT arm when VEGFR2 expression was positive. In conclusion, CCRT plus Endostar significantly improved DMFS but not PFS over CCRT alone. The addition of Endostar could significantly improve survival for patients with positive VEGFR2 expression.  相似文献   
8.
张静  邓卓  李玢  张瑜  杜善平 《现代肿瘤医学》2019,(13):2368-2372
目的:探讨腹腔镜与传统开腹手术治疗子宫内膜癌的临床效果差异。方法:回顾性分析陕西省人民医院2013年10月至2018年3月114例确诊为子宫内膜癌并以腹腔镜治疗的患者为研究对象(腹腔镜组),以同期62例开腹手术治疗的子宫内膜癌病例为对照组,两组在手术时间、术中出血量、淋巴结清扫个数、术后膀胱功能恢复时间、排气时间、体温恢复时间、住院时间及并发症等各方面指标进行比较。结果:腹腔镜组术中失血量、输血率、术后体温恢复时间、肠道功能恢复时间、膀胱功能恢复时间、术后住院天数及手术并发症发生率显著低于开腹组(P<0.05)。腹腔镜组与开腹组在手术时间、术中清扫淋巴结数目、复发率及总生存率差异无统计学意义。结论:与传统方法相比,腹腔镜手术短期效果良好,生存率相当,在具备丰富的腹腔镜手术经验、完善的腹腔镜设备的条件下,可以广泛应用于子宫内膜癌患者的治疗。  相似文献   
9.
Solute carrier family 12 member 5 (SLC12A5) has an oncogenic role in bladder urothelial carcinoma. The present study aimed to characterize the molecular mechanisms of SLC12A5 in bladder urothelial carcinoma pathogenesis. Functional assays identified that in bladder urothelial carcinoma SLC12A5 interacts with and stabilizes SOX18, and then upregulates matrix metalloproteinase 7 (MMP7). In vivo and in vitro assays were performed to confirm the effect of SLC12A5’s interaction with SOX18 on MMP7‐mediated bladder urothelial carcinoma progression. SLC12A5 was upregulated in human bladder tumors, and correlated with the poor survival of patients with bladder urothelial carcinoma tumor invasion and metastasis, promoted by SLC12A5 overexpression. We demonstrated that SLC12A5 interacted with SOX18, and then upregulated MMP7, thus enhancing tumor progression. Importantly, SLC12A5 expression correlated positively with SOX18 and MMP7 expression in bladder urothelial carcinoma. Furthermore, SLC12A5 expression was suppressed by miR‐133a‐3p. Ectopic expression of SLC12A5 partly abolished miR‐133a‐3p‐mediated suppression of cell migration. SLC12A5‐SOX18 complex‐mediated upregulation on MMP7 was important in bladder urothelial carcinoma progression. The miR‐133a‐3p/SLC12A5/SOX18/MMP7 signaling axis was critical for progression, and provided an effective therapeutic approach against bladder urothelial carcinoma.  相似文献   
10.
目的 建立自我信心、动机和权威建议影响儿童安全座椅使用的模型,并通过结构方程模型进行验证,为推动儿童安全座椅使用宣传倡导工作提供科学依据。方法 采用多阶段整群随机抽样方法,在上海市和深圳市调查9 112位拥有≥ 1辆私家轿车且有0~6岁儿童家庭的儿童监护人关于儿童安全座椅使用的情况,构建自我信心、动机和权威建议影响儿童安全座椅使用的模型,通过结构方程模型对理论模型进行验证和量化分析。结果 整体模型符合预期理论模型,且拟合情况较好,指标均达到标准。RMSEA=0.03,CFI=0.97。各路径标准化系数均有统计学意义(P<0.05)。权威建议和动机对自我信心的影响标准化系数分别为0.45和0.30,自我信心对儿童安全座椅使用的影响标准化系数为0.40。权威建议对动机的影响标准化系数为0.61。结论 在儿童安全座椅宣传倡导工作中应重视使用来源于专业权威、具备较好公信力和公益性的专家及机构组织的建议,应将儿童道路交通安全现况和安全座椅作用机制作为宣传重点之一。  相似文献   
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