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51.
目的优化1,8-桉叶油素(1,8-cineole,1,8-Cin)自微乳给药系统(1,8-cineole self-microemulsion drug delivery system,1,8-Cin-SMEDDS)处方,对其进行表征并进行细胞摄取考察。方法通过绘制伪三元相图,确定1,8-Cin-SMEDDS有效自乳化区域,进行初步处方筛选。以粒径和载药量为指标,采用星点设计-效应面法对1,8-Cin-SMEDDS处方进行优化并验证。荧光显微镜观察高糖损伤的人脐静脉内皮细胞(HUVEC)对1,8-Cin-SMEDDS的摄取情况。结果 1,8-Cin-SMEDDS的最佳处方是大豆油(7.5%)与1,8-Cin(22.5%)为混合油相,HS15(56%)为乳化剂,乙醇(14%)为助乳化剂,滴加纯水至8m L得半透明略带蓝色乳光液体。透射电镜观察其外观呈球形液滴,激光粒度Zeta电位测定仪测得平均粒径为(131.68±1.44)nm,Zeta电位为(-10.03±1.63)m V;HPLC法测得包封率为(99.890±0.012)%,载药量为(224.750±0.028)mg/g。HUVEC细胞摄取实验结果表明,细胞对1,8-Cin-SMEDDS的摄取高于游离1,8-Cin。结论 1,8-Cin-SMEDDS制备方法简便,重复性好,所得1,8-Cin-SMEDDS外观良好,包封率高,理化性质稳定,且能促进细胞摄取。  相似文献   
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Background and aimsWe aimed to investigate the impact of vascular resection (VR) on postoperative outcomes and survival of patients undergoing hepatectomy for intrahepatic cholangiocarcinoma (ICC).MethodsA retrospective analysis of a multi-institutional series of 270 patients with resected ICC was carried out. Patients were divided into three groups: portal vein VR (PVR), inferior vena cava VR (CVR) and no VR (NVR). Univariate and multivariate analysis were applied to define the impact of VR on postoperative outcomes and survival.ResultsThirty-one patients (11.5%) underwent VR: 15 (5.6%) to PVR and 16 (5.9%) to CVR. R0 resection rates were 73.6% in NVR, 73.3% of PVR and 68.8% in CVR. The postoperative mortality rate was increased in VR groups: 2.5% in NVR, 6.7% in PVR and 12.5% in CVR. The 5-years overall survival (OS) rates progressively decreased from 38.4% in NVR, to 30.1% in CVR and to 22.2% in PVR, p = 0.030. However, multivariable analysis did not confirm an association between VR and prognosis. The following prognostic factors were identified: size ≥50 mm, patterns of distribution of hepatic nodules (single, satellites or multifocal), lymph-node metastases (N1) and R1 resections. In the VR group the 5-years OS rate in patients without lymph-node metastases undergoing R0 resection (VRR0N0) was 44.4%, while in N1 patients undergoing R1 resection was 20% (p < 0.001).ConclusionVascular resection (PVR and CVR) is associated with higher operative risk, but seems to be justified by the good survival results, especially in patients without other negative prognostic factors (R0N0 resections).  相似文献   
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PurposeThis study evaluated the factors affecting contralateral and ipsilateral recurrent deep vein thrombosis (DVT) after iliac vein stent placement in patients with iliac vein compression syndrome (IVCS).Materials and MethodsData from 130 patients (95 female patients) who underwent catheter-directed thrombolysis and stent placement for IVCS with left lower leg thrombosis at a single institution were retrospectively analyzed. Mean patient age was 69.0 ± 14.0 years old. Median follow-up was 14 months (range, 3–164 months). Anticoagulation therapy was prescribed for 6 months, followed by lifelong antiplatelet therapy. Multivariate logistic regression analysis was performed to evaluate the factors affecting the development of contralateral and ipsilateral recurrent DVT.ResultsSeven patients (5.4%) developed contralateral DVT (median, 26 months; range, 2–61 months), and 11 patients (8.5%) developed ipsilateral DVT (median, 1 month; range, 0–53 months). Stent location (odds ratio [OR], 11.564; 95% confidence interval [CI], 1.159–115.417) and in-stent thrombosis during follow-up (OR, 15.142; 95% CI, 1.406–163.119) were predictors of recurrent contralateral DVT. Thrombophilia (OR, 47.560; 95% CI, 2.369–954.711), remaining inferior vena cava filter (OR, 30.552; 95% CI, 3.495–267.122), and in-stent thrombosis during follow-up (OR, 82.057; 95% CI, 2.915–2309.848) were predictors of ipsilateral DVT.ConclusionsContralateral DVT occurs late and is associated with extension of the iliac vein stent to the inferior vena cava and in-stent thrombosis. Ipsilateral DVT occurs relatively early and is associated with thrombophilia, remaining inferior vena cava filter, and in-stent thrombosis.  相似文献   
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《药学学报(英文版)》2020,10(8):1453-1475
Angiokinases, such as vascular endothelial-, fibroblast- and platelet-derived growth factor receptors (VEGFRs, FGFRs and PDGFRs) play crucial roles in tumor angiogenesis. Anti-angiogenesis therapy using multi-angiokinase inhibitor has achieved great success in recent years. In this study, we presented the design, synthesis, target identification, molecular mechanism, pharmacodynamics (PD) and pharmacokinetics (PK) research of a novel triple-angiokinase inhibitor WXFL-152. WXFL-152, identified from a series of 4-oxyquinoline derivatives based on a structure–activity relationship study, inhibited the proliferation of vascular endothelial cells (ECs) and pericytes by blocking the angiokinase signals VEGF/VEGFR2, FGF/FGFRs and PDGF/PDGFRβ simultaneously in vitro. Significant anticancer effects of WXFL-152 were confirmed in multiple preclinical tumor xenograft models, including a patient-derived tumor xenograft (PDX) model. Pharmacokinetic studies of WXFL-152 demonstrated high favourable bioavailability with single-dose and continuous multi-dose by oral administration in rats and beagles. In conclusion, WXFL-152, which is currently in phase Ib clinical trials, is a novel and effective triple-angiokinase inhibitor with clear PD and PK in tumor therapy.  相似文献   
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目的 探讨颅内深静脉血栓形成(deep cerebral venous thrombosis,DCVT)的临床诊断与治疗策略。 方法 回顾性分析10年来影像学诊断为DCVT的5例患者的临床表现、影像学特征、治疗及预后情况。 结果 DCVT最常累及Rosenthal基底静脉、大脑内静脉、Galen静脉和直窦,其临床表现不典型,常见有头痛、意识障碍、复视、偏瘫等,常见诱发因素有口服避孕药、产褥期、妊娠期等。丘脑水肿为DCVT患者最常见的影像学征象。肝素抗凝治疗简单有效,大脑深静脉可恢复再通,临床症状缓解。 结论 DCVT患者临床症状缺乏特异性,早期诊断困难,特殊成像技术和特定影像学特征有助于其明确诊断,及时正确的抗凝治疗可获得良好的预后。  相似文献   
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目的探讨脑源性微囊泡(BDMVs)对脐静脉内皮细胞骨架的影响。方法体外制备BDMVs,并予透射电镜观察及粒径检测。将PKH26荧光染料标记的BDMVs与脐静脉内皮细胞共培养0.5 h、1 h、2 h后,应用流式细胞术检测不同时间点的脐静脉内皮细胞吞噬BDMVs情况。将体外常规培养的脐静脉内皮细胞分为对照组、BDMVs组(加入终浓度1.5×10^7/mL的BDMVs处理细胞)及尼莫地平组[予2μg尼莫地平(0.2 mg/mL)预处理10 min后加入终浓度1.5×10^7/mL的BDMVs处理细胞],应用激光共聚焦显微镜观察罗丹明标记鬼笔环肽染色后各组脐静脉内皮细胞中纤维型肌动蛋白的荧光强度及应力纤维数目。结果透射电镜下可见体外制备的BDMVs具有完整的膜结构,粒径范围为100~1000 nm。流式细胞术检测显示,吞噬BDMVs的脐静脉内皮细胞比例随培养时间的延长呈时间依赖性升高(0.5 h:22.7%±1.2%;1 h:52.3%±1.3%;2 h:71.6%±1.9%),各时间点间两两比较差异均有统计学意义(P<0.05)。激光共聚焦显微镜观察显示,与对照组相比,BDMVs组中纤维型肌动蛋白的荧光强度明显升高且应力纤维数目明显增多增粗;而与BDMVs组相比,尼莫地平组中纤维型肌动蛋白的荧光强度明显降低且应力纤维数目明显减少变细。结论脐静脉内皮细胞吞噬BDMVs的作用随时间延长而增强,且吞噬BDMVs后可导致细胞骨架重构,而尼莫地平可部分阻断该作用。  相似文献   
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