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排序方式: 共有562条查询结果,搜索用时 15 毫秒
501.
目的:探讨单孔胸腔镜肺癌根治术后使用单根胸腔引流管联合负压引流管的效果。方法:选取2018年1月~2020年1月于我院行单孔胸腔镜肺癌根治术的肺癌患者100例为研究对象,采用随机数字表法分为两组,对照组患者放置一根30#多孔胸管,观察组在对照组的基础上放置一根负压引流管。比较两组患者的围术期相关指标、并发症的发生情况、手术VAS评分及CRP及PCT水平的变化情况。结果:两组患者总引流管留置时间和胸腔总引流量相比无统计学差异(P>0.05)。观察组患者的30#多孔胸管留置时间、住院时间及再次胸腔穿刺率显著短于/低于对照组(P<0.05),肺不张、漏气、积液或积气等总并发症发生率显著低于对照组(P<0.05);术后3 d和术后5 d的VAS评分均显著低于对照组(P<0.05),术后3 d的CRP及PCT水平显著低于对照组(P>0.05)。结论:单孔胸腔镜肺癌根治术后使用单根胸腔引流管联合负压引流管可显著减轻患者的疼痛,缩短30#多孔胸管留置时间及住院时间,降低再次胸腔穿刺率及并发症发生率,同时可缓解患者的炎症状态。 相似文献
502.
目的:用动脉瘤栓塞体积比评价颅内动脉瘤栓基术的治疗效果,观察颅内动脉瘤栓塞术治疗颅内动脉瘤的影响因素及颅内动脉瘤栓塞术的术后情况。方法:选取112例行血管内栓塞治疗的患者为研究对象,按术后动脉瘤栓塞体积比分成VER〉25%和VER〈25%两组,观察不同的栓塞材料(电解可脱弹簧圈、水解可脱弹簧圈)和术中血管的痉挛程度(轻、中、重)对栓塞程度的影响;术后随访106例病人,按动脉瘤栓塞体积比分成VER〉25%和VER〈25%两组,统计两组患者的再出血率和复发率,用动脉瘤栓塞体积比评价栓塞术的预后效果。结果:动脉瘤栓塞体积比VER〉25%和VER〈25%两组间进行比较,不同血管痉挛情况下和使用不同的栓塞材料在两组间均存在显著差异(P〈O.05),具有统计学意义;术后随访半年,比较VER〉25%和VER〈25%两组的再出血率也有显著差异(P〈O.05),具有统计学意义。结论:动脉瘤栓塞体积比在评价颅内动脉瘤栓塞术中有重要意义,血管痉挛情况、栓塞材料是影响颅内动脉瘤栓塞术栓塞疗效的主要影响因素;术后随访证实动脉瘤栓塞体积比对评价动脉瘤栓塞术的预后有一定的作用。 相似文献
503.
F. Auricchio M. Conti A. Reali 《Computer methods in biomechanics and biomedical engineering》2014,17(12):1347-1357
Until recently, heart valve failure has been treated adopting open-heart surgical techniques and cardiopulmonary bypass. However, over the last decade, minimally invasive procedures have been developed to avoid high risks associated with conventional open-chest valve replacement techniques. Such a recent and innovative procedure represents an optimal field for conducting investigations through virtual computer-based simulations: in fact, nowadays, computational engineering is widely used to unravel many problems in the biomedical field of cardiovascular mechanics and specifically, minimally invasive procedures. In this study, we investigate a balloon-expandable valve and we propose a novel simulation strategy to reproduce its implantation using computational tools. Focusing on the Edwards SAPIEN valve in particular, we simulate both stent crimping and deployment through balloon inflation. The developed procedure enabled us to obtain the entire prosthetic device virtually implanted in a patient-specific aortic root created by processing medical images; hence, it allows evaluation of postoperative prosthesis performance depending on different factors (e.g. device size and prosthesis placement site). Notably, prosthesis positioning in two different cases (distal and proximal) has been examined in terms of coaptation area, average stress on valve leaflets as well as impact on the aortic root wall. The coaptation area is significantly affected by the positioning strategy ( ? 24%, moving from the proximal to distal) as well as the stress distribution on both the leaflets (+13.5%, from proximal to distal) and the aortic wall ( ? 22%, from proximal to distal). No remarkable variations of the stress state on the stent struts have been obtained in the two investigated cases. 相似文献
504.
A.J. van Hell A. KlymchenkoD.M. Gueth W.J. van BlitterswijkG.A. Koning M. Verheij 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(9):1301-1307
The endothelial lining and its outer lipid membrane are the first major barriers drug molecules encounter upon intravenous administration. Our previous work identified lipid analogs that counteract plasma membrane barrier function for a series of amphiphilic drugs. For example, short-chain sphingolipids (SCS), like N-octanoyl-glucosylceramide, effectively elevated doxorubicin accumulation in tumor cells, both in vitro and in vivo, and in endothelial cells, whereas other (normal) cells remained unaffected. We hypothesize here that local membrane lipid composition and the degree of lipid ordering define SCS efficacy in individual cells. To this end, we study the differential effect of SCS on bovine aortic endothelial cells (BAEC) in its confluent versus proliferative state, as a model system. While their (plasma membrane) lipidome stays remarkably unaltered when BAECs reach confluency, their lipids segregate to form apical and basolateral domains. Using probe NR12S, we reveal that lipids in the apical membrane are more condensed/liquid-ordered. SCS preferentially attenuate the barrier posed by these condensed membranes and facilitate doxorubicin influx in these particular membrane regions. We confirm these findings in MDCK cells and artificial membranes. In conclusion, SCS-facilitated drug traversal acts on condensed membrane domains, elicited by confluency in resting endothelium. 相似文献
505.
506.
摘要目的:用动脉瘤栓塞体积比评价颅内动脉瘤栓塞术的治疗效果,观察颅内动脉瘤栓塞术治疗颅内动脉瘤的影响因素及颅内
动脉瘤栓塞术的术后情况。方法:选取112例行血管内栓塞治疗的患者为研究对象,按术后动脉瘤栓塞体积比分成VER≥ 25%和
VER<25%两组,观察不同的栓塞材料(电解可脱弹簧圈、水解可脱弹簧圈)和术中血管的痉挛程度(轻、中、重)对栓塞程度的影
响;术后随访106 例病人,按动脉瘤栓塞体积比分成VER≥ 25%和VER<25%两组,统计两组患者的再出血率和复发率,用动脉
瘤栓塞体积比评价栓塞术的预后效果。结果:动脉瘤栓塞体积比VER≥ 25%和VER<25%两组间进行比较,不同血管痉挛情况下
和使用不同的栓塞材料在两组间均存在显著差异(P<0.05),具有统计学意义;术后随访半年,比较VER≥ 25%和VER<25%两组
的再出血率也有显著差异(P<0.05),具有统计学意义。结论:动脉瘤栓塞体积比在评价颅内动脉瘤栓塞术中有重要意义,血管痉挛
情况、栓塞材料是影响颅内动脉瘤栓塞术栓塞疗效的主要影响因素;术后随访证实动脉瘤栓塞体积比对评价动脉瘤栓塞术的预
后有一定的作用。 相似文献
507.
Fu Gao Pierre Chambon Stefan Offermanns George Tellides Wei Kong Xiaoming Zhang Wei Li 《Biochemical and biophysical research communications》2014
Transforming growth factor-β (TGF-β) signaling has been significantly implicated in the pathogenesis of aneurysm, prominently the initiation and progression of abdominal aortic aneurysm (AAA). Vascular smooth muscle cell (SMC) is the principal resident cell in aortic wall and is essential for its structure and function. However, the role of TGF-β pathway in SMC for the formation of AAA remains unknown. Therefore, the goal of the present study was to investigate the effect of TGF-β pathway in SMC for AAA pathogenesis, by using a genetical smooth muscle-specific (SM-specific) TGF-βtype II receptor (Tgfbr2) disruption animal model. Mice deficient in the expression of Tgfbr2 (MyhCre.Tgfbr2f/f and MyhCre.Tgfbr2WT/f) and their corresponding wild-type background mice (MyhCre.Tgfbr2WT/WT) underwent AAA induction by infrarenal peri-adventitial application of elastase. Fourteen days after elastase treatment, the aortas were analyzed and indicated that disruption of 1 or 2 alleles of Tgfbr2 in SMC provided markedly step-wise protection from AAA formation. And elastin degradation, medial SMC loss, macrophage infiltration, and matrix metalloproteinases (MMP) expression were all significantly reduced in Tgfbr2 deletion mice. Our study demonstrated, for the first time, that the TGF-β signaling pathway in SMC plays a critical role in AAA and disruption can prevent the aneurysm formation. 相似文献
508.
Shunsuke Netsu Tetsuro Shishido Tatsuro Kitahara Yuki Honda Akira Funayama Taro Narumi Shinpei Kadowaki Hiroki Takahashi Takuya Miyamoto Takanori Arimoto Satoshi Nishiyama Tetsu Watanabe Chang-Hoon Woo Yasuchika Takeishi Isao Kubota 《Biochemical and biophysical research communications》2014
Midkine is a multifunctional growth factor, and its serum levels are increased with the functional severity of heart failure. This study aimed to examine the role of midkine in heart failure pathogenesis. Midkine expression levels were increased in the kidney and lung after transverse aortic constriction (TAC) surgery, but not sufficiently increased in the heart. After TAC, phosphorylation of extracellular signal-regulated kinase1/2 and AKT, and the expression levels of foetal genes in the heart were considerably increased in transgenic mice with cardiac-specific overexpression of midkine (MK-Tg) compared with wild-type (WT) mice. MK-Tg mice showed more severe cardiac hypertrophy and dysfunction, and showed lower survival rate after TAC than WT mice. We conclude that midkine plays a critical role in cardiac hypertrophy and remodelling. 相似文献
509.
《Journal of biomechanics》2014,47(16):3820-3824
We recently reported a mechanistic model to link micro-architectural information to the delamination strength (Sd) of human ascending thoracic aorta (ATA). That analysis demonstrated that the number density (N) and failure energy (Uf) of the radially-oriented collagen fibers contribute to the Sd of both aneurysmal (ATAA) and non-aneurysmal (CTRL-ATA) aortic tissue. Among the set of ATAA samples, we studied specimens from patients displaying bicuspid (BAV) and tricuspid aortic valve (TAV) morphologic phenotypes. Results from our prior work were based on the assumption that the Uf was independent of dissection direction. In the current study, we excluded that assumption and hypothesized that Uf correlates with the Sd of ATAA. To test the hypothesis, we used previously-reported experimentally-determined Sd measurements and N of radially-oriented collagen fibers as input in our validated mechanistic model to calculate Uf for BAV-ATAA, TAV-ATAA and CTRL-ATA tissue specimens. The results of our analysis revealed that Uf is significantly lower for both BAV-ATAA and TAV-ATAA compared to CTRL-ATA cases, and does not differ between BAV-ATAA and TAV-ATAA. Furthermore, we found that Uf is consistent between circumferential-radial and longitudinal-radial planes in either of BAV-ATAA, TAV-ATAA or CTRL-ATA specimens. These findings employ a novel mechanistic model to increase our understanding of the putative interrelationship between biomechanical properties, extracellular matrix biology, and failure energy of aortic dissection. 相似文献
510.
The effects of stent interaction on porcine urinary bladder matrix employed as stent-graft materials
Deployment of stent-grafts, derived from synthetic biomaterials, is an established minimally invasive approach for effectively treating abdominal aortic aneurysms (AAAs). However, a notable disadvantage associated with this surgical technique is migration of the deployed stent-graft due to poor biocompatibility and inadequate integration in vivo. Recently, tissue-engineered extracellular matrices (ECMs) have shown early promise as integrating stabilisation collars in this setting due to their ability to induce a constructive tissue remodelling response after in vivo implantation. In the present study the effects of stent loading on an ECM?s mechanical properties were investigated by characterising the compression and loading effects of endovascular stents on porcine urinary bladder matrix (UBM) scaffolds. Results demonstrated that the maximum stress was induced when the stent force was 8-times higher than a standard commercially available stent-graft and this represented about 20% of the failure strength of the UBM material. In addition, the influence of stent shape was also investigated. Findings demonstrated that the stress induced was higher for circular stents at low forces and a higher stress was induced on square stents when increased force was applied. Our findings demonstrate that porcine UBM possesses sufficient mechanical strength to withstand the compression and loading effects of commercially available stent-grafts in the setting of endovascular aneurysm repair. 相似文献