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目的:对食管胃结合部腺癌近端胃切除术(PG)人工三角瓣成形后残胃食糜进行流体动力学数值模拟,并计算不同性质胃内食糜的流动特征。方法:构建常规PG和人工三角瓣成形术术后胃仿真模型,运用Fluent软件对不同粘度胃内食糜反流问题进行数值模拟。结果:站立位姿态时,相对常规PG方案,人工三角瓣成形手术方案表现出较好的抗反流作用;卧位姿态时,当胃内食糜粘度大于0.145 2 Pa[?s,且胃内食糜不超过人工三角瓣情况下,人工三角瓣成形抗反流手术表现出较好的抗反流效果;人工三角瓣抗反流成形手术方案数值模拟结果与临床上患者表现一致。结论:本研究仿真分析为人工三角瓣成形抗反流手术方案的有效性机理分析、临床患者术后饮食及手术方案的进一步改进提供理论及数值依据。
【关键词】食管胃结合部腺癌;抗反流;人工三角瓣;计算流体力学 相似文献
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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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Anti-Oxidant,Anti-Hemolytic Effects of Crataegus aronia Leaves and Its Anti- Proliferative Effect Enhance Cisplatin Cytotoxicity in A549 Human Lung Cancer Cell Line 下载免费PDF全文
Islam OmairiFiras Kobeissy Salam Nasreddine 《Asian Pacific journal of cancer prevention》2020,21(10):2993-3003
Objective: For Arabian traditional medicine, Crataegus aronia syn. Azarolus (L) Bosc. ex DC (Rosaceae) is widely used to treat diabetes, sexual weakness, cardiovascular diseases and cancer. The anti-cancerous and anti-hemolysis effects of the hydroalcoholic extract of this plant have never been investigated before. The present study aims to evaluate the biological activities of the hydroalcoholic extract of Crataegus aronia leaves in combination with cisplatin, one of the most widely employed chemotherapeutics, on A549 human lung cancer cell line. Methods: The anti-oxidant and anti-proliferative activities of leaves, fruits, seeds of C. aronia were investigated by DPPH method and MTT assay; respectively. Cell migration activity was investigated by wound healing and by cell aggregation assays. The effect of C. aronia in inducing cell cycle arrest along with activating cell apoptosis was evaluated by flow cytometry and Western blot assays, respectively. Results: Our results showed that C. aronia leaves (C. aronia L.) had the highest anti-oxidant and anti-proliferative activities. The leaves extract was potent against hemolysis of the human erythrocytes and showed elevated decrease in migration by reducing wound healing migration and by increasing cell aggregation. Finally, C. aronia L. treatment exhibited apoptotic activity on A549 cells by the down-regulation of PARP-1, caspase-3 and Bcl-2 proteins and by increasing the percentage of A549 cells in sub G0 cell cycle. Moreover, the co-treatment of C. aronia L. and cisplatin remarkably sensitised A549 cells to cisplatin. Conclusion: The results suggested that C. aronia L. could be used as a potential treatment against human lung cancer exhibiting minimal side effects on human health. 相似文献
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Signaling by the transforming growth factor-β (TGF-β) superfamily is important in the regulation of hematopoiesis and is dysregulated in myelodysplastic syndromes (MDS), contributing to ineffective hematopoiesis and clinical cytopenias. TGF-β, activins and growth differentiation factors exert inhibitory effects on red cell formation by activating canonical SMAD2/3 pathway signaling. SMAD2/3 overactivation is seen in numerous subtypes of MDS. Furthermore, reduced levels of inhibitory SMAD7 are 相似文献
References
- 1.Valcarcel D, Verma A, Platzbecker U, et al. Phase 2 Study of Monotherapy Galunisertib (LY2157299 Monohydrate) in Very Low-, Low-, and Intermediate-Risk Patients with Myelodysplastic Syndromes. Blood. 2015;126:1669.
- 2.Suragani RN, Cawley SM, Li R, Wallner S, et al. Modified activin receptor IIB ligand trap mitigates ineffective erythropoiesis and disease complications in murine β-thalassemia. Blood. 2014 Jun 19;123(25):3864-72.
- 3.Dussiot M, Maciel TT, Fricot A, et al. Nat Med. 2014 Apr;20(4):398-407.
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本文通过收集1989年1月至2019年12月国内学者发表在国内外期刊上的文献及参考文献,共纳入符合标准的140例恶性淋巴瘤(malignant lymphoma,ML)合并自身免疫性血细胞减少(autoimmune cytopenia,AIC)病例,包括溶血性贫血(autoimmune hemolytic anemia,AIHA)、免疫性血小板减少症(immune thrombocytopenia,ITP)、纯红细胞再生障碍性贫血(pure red cell aplasia,PRCA)及Evans综合征等。虽然各亚型淋巴瘤病例数均较少(n=1~28),但通过系统性分析仍得到部分有意义的发现。除免疫性中性粒细胞减少(autoimmune neutropenia,AIN)外,各类AIC均有报道,发生率依次为AIHA>ITP>冷凝集素综合征(cold agglutinin syndrome,CAS)>PRCA>Evans综合征。AIC见于各亚型淋巴瘤,但各类AIC在不同亚型发生率存在差异。CAS仅见于淋巴瘤B细胞非霍奇金淋巴瘤(B cell nonHodgkin′slymphoma,B-NHL)、AIHA、ITP,Evans综合征多见于B-NHL,PRCA则多见于T细胞非霍奇金淋巴瘤(T cell non Hodgkin′s lymphoma,T-NHL)。相较于糖皮质激素等常规治疗,合并ML的AIC抗肿瘤治疗对有效率更高。恶性淋巴瘤合并AIC临床情况复杂,需引起临床关注。 相似文献
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余春姣 《中国继续医学教育》2020,(6):196-198
目的研究地中海贫血孕妇实施产科综合护理模式的护理配合措施及效果。方法选择78例于我院检查地中海贫血孕妇,纳入时间为2017年5月-2018年5月,采用随机数字表法将其分为综合护理组与对照组,每组均39例。其中对照组采用常规护理形式,综合护理组行产科综合护理模式,对比综合护理组与对照组护理前后心理状态评估指标及家属的护理满意度。结果护理前综合护理组与对照组患者心理状态评估指标差异无统计学意义(P>0.05),与对照组(76.92%)相比,护理后综合护理组焦虑指标、抑郁指标更低,综合护理组孕妇及家属的护理满意度(94.87%)较高(P<0.05)。结论通过综合护理模式可提升地中海贫血孕妇护理满意度,并改善其心理状态。 相似文献
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Muberra Namli Kalem Ziya Kalem Nilufer Akgun Ebru Yuce Hatice Aktas 《The journal of maternal-fetal & neonatal medicine》2019,32(6):954-960
Aim: The aim of this study was to investigate the possible maternal and fetal factors, which affect the Umbilical Coiling Index (UCI).Methods: This prospective, observational, analytic study was conducted using the data of 380 women with term pregnancy and newborns who presented at a University Hospital. Hemoglobin (Hb), ferritin, iron, and the total iron binding capacity (TIBC) of the maternal blood were measured, and transferrin saturation was estimated based on the ratio between serum iron and TIBC. Blood gases, ferritin, iron, and TIBC of the umbilical cord were also measured, and the transferrin saturation was calculated. The length and thickness of the umbilical cord, numbers of coilings, weight of placenta, neonatal weight were registered. The UCI was calculated dividing the total number of coils by the length of the umbilical cord (in cm).Results: A positive, linear, and statistically significant relationship was found between the UCI scores and the umbilical cord blood transferrin saturation, umbilical cord thickness, and the first- and fifth-min APGAR scores (p?=?.044, p?.001, p?=?.008, p?=?.022, respectively). No statistically significant relationship was found between the maternal Hb values and the UCI scores (p?=?.472). In addition, there was no statistically significant relationship between the UCI scores and maternal ferritin, maternal transferrin saturation and umbilical cordon ferritin levels (p?=?.940, p?=?.681, and p?=?.975, respectively).Conclusions: A positive correlation was found between the UCI and umbilical cord transferrin saturation and between the newborn APGAR scores. However, this finding is not sufficient to explain the relationship of the umbilical cord dynamics with the newborn wellbeing and coiling. 相似文献
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