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101.
目的 探讨门静脉结扎术(PVL)后,肝脏血流动力学变化与荷瘤大鼠不同肝叶肿瘤生长的关系.方法 将18只雄性大鼠随机分为A、B组.均为荷瘤大鼠,A组行PVL术,B组为假手术组.分别于术后不同时间段,应用多普勒超声测量结扎肝叶与非结扎肝叶肝动脉及门静脉血流速度,正电子发射计算机断层显像(PET-CT)测算结扎与非结扎肝叶上肿瘤的体积变化,分析血流变化与肿瘤体积变化是否存在相关性.结果 A组PVL肝叶肝动脉血流速度明显高于B组[(4.34±0.53) ml/min比(2.07±0.04) ml/min,P<0.05],且与结扎肝叶肿瘤体积增加呈正相关(r=0.908,P<0.05).结论 PVL肝叶的肝动脉血流增加是PVL术后结扎侧肝叶肿瘤生长加速的促进因素.  相似文献   
102.
We previously reported Rho kinase is involved in vessel hyper-permeability caused by burns. Here we further explore the Rho kinase downstream signaling, it is found that its specific inhibitor Y27632 significantly diminishes the activation of JNK and p38 MAPKs but not ERK that induced by serum from burned rats (burn-serum). JNK activation was found involved in the expression of HUVEC adhesion molecules following thermal injury, although not in the process of stress fiber formation. Inhibition of various MAPKs by specific inhibitors showed that SB203580 (inhibitor of p38), but neither SP600125 (inhibitor of JNK) nor PD98059 (inhibitor of ERK), abolish activation of the p38 downstream kinase MK2. Demonstration of stress fibers by fluorescent-labeled phalloidin showed that inhibition of MK2, either by its specific inhibitor or by dominant negative adeno-viral-carried constructs, significantly reduced burn-serum-induced HUVEC stress-fiber formation, while inhibition of another downstream p38 MAPK kinase, PRAK, had no such effects. Transfection of dominant negative adeno-viral MK2 (Ad-MK2(A)) significantly inhibited thermal injury-induced blood vessel hyper-permeability in rats and, moreover, prolonged the survival of burned rats beyond 72 h following thermal injury. One of the mechanisms behind these phenomena is that Ad-MK2(A) causes a significant depression of burn-serum-induced HSP27-phosphorylation, while the adeno-viral transported dominant negative PRAK (Ad-PRAK(A)) does not block. Although the effect of blockade of MK2 through its adeno-viral approach requires further study and investigation of alternatives to know for sure, we may have found a new pathway behind thermal-injury-induced blood vessel hyper-permeability, namely: Rho kinase > p38 > MK2 > HSP27.  相似文献   
103.

Introduction

Current guidelines on venous thromboembolism (VTE) prevention do not reflect the potential varying risk for patients undergoing different urological procedures. Our study aimed to establish the procedure specific rate of postoperative VTE in patients undergoing urological surgery.

Methods

Hospital Episode Statistics were obtained for all patients undergoing common urological procedures between April 2009 and April 2010. This cohort was followed up to identify all patients reattending with either deep vein thrombosis (DVT) or pulmonary embolism (PE) within 12 months.

Results

A total of 126,891 individuals underwent urological surgery during the study period. This included 89,628 men (70.6%) and 37,236 women (29.3%) with a mean age of 65.2 years. At the 12-month follow-up, 839 patients (0.66%) were readmitted with VTE. Of these, 373 (0.29%) were admitted with DVT and 466 (0.37%) with PE. The procedure-specific rate of VTE varied significantly between 2.86% following cystectomy and 0.23% following urethral dilatation. Procedures performed in the lithotomy position carried a significantly lower risk of VTE than those performed in the supine position (0.60% vs 1.28%, p<0.0001). Furthermore, of all procedures performed in the lithotomy position, those performed on benign conditions carried a significantly lower risk than those performed on malignant disease (0.52% vs 0.79%, p<0.0001).

Conclusions

Procedure specific rates of postoperative VTE vary widely among patients undergoing urological procedures. These findings suggest the potential benefit of prolonging the use of thromboprophylaxis in high-risk patients but also exploring the apparent lack of need for routine thromboprophylaxis in patients undergoing low-risk procedures.  相似文献   
104.
An ovine iliac vein thrombosis model was devised to test a wall-contacting rotational thrombectomy device. Thrombosis was successfully induced in 9 sheep with an average clot length of 31 mm ± 12 and >60% vessel occlusion on angiography. The thrombus was subsequently removed, maintaining normal intraoperative pulmonary arterial pressure (5.9 mm Hg ± 3.6) and complete distal reperfusion after thrombectomy. Additionally, the sheep were without signs of vascular trauma or embolic complications on gross necropsy and histopathologic analysis. The findings from this study support the use of an ovine iliac deep vein thrombosis model for testing of a lower extremity thrombectomy device.  相似文献   
105.
PurposeTo evaluate the effectiveness and safety of fluoroscopy-guided percutaneous high ligation (FPHL) combined with fluoroscopy-guided foam sclerotherapy (FGFS) to treat varicose veins of the great saphenous veins (GSVs).Materials and MethodsThis was a retrospective study of 113 patients (mean age, 62.1 ± 10.8 years; 60 men) with varicose veins of the GSVs (133 limbs) that were treated with FPHL combined with FGFS between April 1 and October 31, 2019. Demographic and clinical data were collected from these patients before the FPHL procedure, after which FGFS was performed. The preterminal GSV was ligated percutaneously by a percutaneously-positioned polypropylene ligature under fluoroscopic guidance. The outcome of ligation was confirmed by venography. Then, foam sclerotherapy was performed under fluoroscopy. At 1-year follow-up, GSV occlusion was evaluated by ultrasound. The venous clinical severity scores (VCSSs) were compared between the preoperative and 1-year follow-up periods.ResultsThe technical success rate was 100% (133 limbs). Complete 12-month follow-up was available for 112 limbs (84.2%) and 103 of these limbs (92.0%) remained occluded during this period. The VCSS improved from 4.71 ± 2.15 to 0.74 ± 0.60 (V = 6328, P < .001). During follow-up, there were 16 limbs with thrombophlebitis and 38 limbs with saphenous junction pain; these events were alleviated within 2 weeks of the procedure. There was no deep venous thrombosis or other severe adverse events.ConclusionsFPHL combined with FGFS to treat varicose veins in the GSVs achieved an occlusion rate of 92% and improved the clinical symptoms within 1 year; this minimally-invasive procedure was safe and effective.  相似文献   
106.
PurposeTo assess the critical role of transjugular intrahepatic portosystemic shunt (TIPS) in the management of Budd-Chiari syndrome (BCS), as the data with respect to the safety and outcome of TIPS in patients with BCS are scarce because of the rarity of the disease.Materials and MethodsA comprehensive search of literature of various databases from 2000 to October 2021 was conducted for studies evaluating the outcome of TIPS in patients with BCS. The primary outcomes of the analysis were technical and clinical success, adverse events and mortality associated with TIPS, dysfunction of TIPS, need for TIPS revision, need for liver transplantation (LT), and 1-year survival.ResultsA total of 33 studies (1,395 patients) were included in this meta-analysis. The pooled rates and 95% confidence intervals of various outcomes were 98.6% (97.6–99.7) for technical success, 90.3% (86.0–94.6) for clinical success, 10.0% (6.5–13.6) for major adverse events, 0.5% (0.2–1.0) for TIPS-related mortality, 11.6% (7.8–15.4) for post-TIPS hepatic encephalopathy (HE), 40.1% (32.5–47.7) for TIPS dysfunction, 8.6% (4.9–12.4) for the need for TIPS revision, 4.5% (2.8–6.2) for the need for LT, and 94.6% (93.1–96.1) for 1-year survival. Publication bias was seen with all outcomes except for post-TIPS HE, TIPS dysfunction, and the need for LT.ConclusionsThe existing literature supports the feasibility, safety, and efficacy of TIPS in the treatment of BCS. Deciding the optimal timing of TIPS in BCS needs further studies.  相似文献   
107.
PurposeTo evaluate temporal trends, practice variation, and associated outcomes with the use of intravascular ultrasound (US) during deep venous stent placement among Medicare beneficiaries.Materials and MethodsAll lower extremity deep venous stent placement procedures performed between January 1, 2017, and December 31, 2019 among Medicare beneficiaries were included. Temporal trends in intravascular US use were stratified by procedural setting and physician specialty. The primary outcome was a composite of 12-month all-cause mortality, all-cause hospitalization, or repeat target vessel intervention. The secondary outcome was a composite of 12-month stent thrombosis, embolization, or restenosis.ResultsAmong the 20,984 deep venous interventions performed during the study period, 15,184 (72.4%) utilized intravascular US. Moderate growth in intravascular US use was observed during the study period in all clinical settings. There was a variation in the use of intravascular US among all operators (median, 77.3% of cases; interquartile range, 20.0%–99.2%). In weighted analyses, intravascular US use during deep venous stent placement was associated with a lower risk of both the primary (adjusted hazard ratio, 0.72; 95% confidence interval [CI], 0.69–0.76; P < .001) and secondary (adjusted hazard ratio, 0.32; 95% CI, 0.27–0.39; P < .001) composite end points.ConclusionsIntravascular US is frequently used during deep venous stent placement among Medicare beneficiaries, with further increase in use from 2017 to 2019. The utilization of intravascular US as part of a procedural strategy was associated with a lower cumulative incidence of adverse outcomes after the procedure, including venous stent thrombosis and embolization.  相似文献   
108.
Background: In adults, placement of the laryngeal mask airway causes increased overlapping of the internal jugular vein (IJV) and common carotid artery (CCA). However, few studies in children have been reported. The aim of this study was to describe the degree of overlap of the IJV and the CCA before and after laryngeal mask airway placement in infants and children. Method: There were 160 children scheduled to undergo Protex® SoftSeal® and Ambu® placement. Patients were initially positioned in the 15° Trendelenburg position with their heads rotated 30° to the left. The ultrasound probe was placed perpendicular to the skin, and the images of the right IJV and CCA were collected at the level of the cricoid cartilage. Following laryngeal mask airway placement, images were collected in the same manner. Results: No statistically significant changes were observed in the overlap index before and after laryngeal mask airway placement. By inflating the laryngeal mask airway cuff, migration of the vessel forward was 24.38% and outward migration was 13.99%. Conclusion: There was no remarkable change in the overlap index before and after laryngeal mask airway placement in children.  相似文献   
109.
目的 探讨脱细胞基质( DCM)人工血管用于小口径血管移植的可行性.方法 40条雄性杂种犬随机分为DCM、膨体聚四氟乙烯(ePTFE)人工血管及自体颈外静脉3组行右颈总动脉置换术,彩超监测移植物通畅率.术后4、8周活体取材,标本行苏木素-伊红(HE)、免疫组织化学染色及扫描电镜检查.结果 3组移植物1周通畅率(75.0%、64.3%、100.0%)差异无统计学意义(P>0.05);自体颈外静脉组4、8周通畅率( 100.0%、88.9%)优于DCM组(56.3%、26.7%)及ePTFE组(57.1%、23.1%,P<0.05),后两组差异无统计学意义(P>0.05).DCM人工血管4、8周血栓形成面积小于ePTFE人工血管,吻合口内膜内皮化程度高于后者.结论 小口径DCM人工血管在抑制血栓形成及加快内皮化方面优于ePTFE人工血管.  相似文献   
110.
目的:探讨并总结铜针留置、铜针留置结合环形缝扎治疗脉管畸形的临床应用体会.方法:采用铜针留置、铜针留置结合环形缝扎治疗脉管畸形患者46例,其中静脉畸形43例,动、静脉畸形3例.治疗1~3 次,其中第1次治疗41例,第2次治疗4例,第3次治疗1例,再次治疗至少间隔6个月.观察铜针留置治疗后患者的局部和全身反应,检测其中6例患者铜针留置治疗前及铜针留置治疗5天后血清铜及肝功能变化,数据结果进行统计学分析并对疗效进行评价.结果:本组治疗患者46例,术后随访6~24个月.临床治疗效果:I级(差)3例,占6.5%;II级(中)11例,占23.9%;III级(好)27例,占58.7%;IV级(优)5例,占10.9%.43例(包括中、好和优)脉管畸形患者获得有效治疗(图2~3),总有效率为93.5%.6例留置铜针治疗5天后,血清铜轻度升高,方差分析显示与治疗前相比无显著性差异(P>0.05);血清丙氨酸氨基转移酶、谷草转氨酶活性轻度升高,秩和检验显示与治疗前相比无显著性差异(P>0.05).结论:铜针留置简单易行、安全性高,对患者组织形态和功能影响小,是治疗脉管畸形的有效方法之一;铜针留置结合环形缝扎是铜针治疗脉管畸形的改进和发展,可以更有效地治疗脉管畸形,适用于治疗病变范围较大、较深的脉管畸形.  相似文献   
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