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51.
ObjectiveThis study aimed to determine predictors of microvascular occlusion (MVO) in patients with ST elevation myocardial infarction (STEMI) after primary percutaneous coronary intervention (pPCI).MethodsThis retrospective, observational study consecutively included 113 patients with STEMI undergoing pPCI. Cardiac magnetic resonance imaging was used to determine the presence of MVO in these patients. Biomarkers in serum were routinely tested 1 day after pPCI. Multivariable logistic regression analysis was used to evaluate significant predictors of occurrence of MVO.ResultsThere were 62 patients in the MVO group and 51 patients in the non-MVO group. C-reactive protein (CRP), thrombomodulin, lymphatic vessel endothelial hyaluronan receptor-1, syndecan-1, and troponin T (TnT) levels after the procedure were significantly higher in the MVO group than in the non-MVO group. CRP (hazard ratio [HR]=1.036), TnT (HR=1.316), and syndecan-1 (HR=1.986) levels were independently associated with MVO in patients with acute myocardial infarction after pPCI.ConclusionsLevels of CRP, TnT, and syndecan-1 can be used as serum biomarkers for MVO in patients with STEMI receiving pPCI.  相似文献   
52.
目的 探讨原发性三叉神经痛(PTN)微血管减压术(MVD)出现困难减压的处理方法以及疗效。方法 回顾性分析2013年1月至2019年12月采用MVD治疗的408例PTN的临床资料。术中出现困难减压56例,常规减压352例。对于困难减压病人,综合采取包括安置腰大池引流、神经内镜辅助、扩大松解桥小脑角区蛛网膜粘连、经小脑水平裂-小脑桥脑裂入路解剖显露,以及“架桥”等方法妥善处理。结果 术后随访0.5~5年。常规减压组术后即刻缓解37例,延迟缓解14例,无效5例;困难减压组术后即刻缓解267例,延迟缓解62例,无效23例。常规减压组术后即刻缓解率(75.85%,267/352)与困难减压组(66.07%,37/56)无统计学差异(P>0.05),常规减压组术后有效率(93.54%,329/352)与困难减压组(91.07%,51/56)无统计学差异(P>0.05)。常规减压组术后总并发症发生率(7.7%,27/352)与困难减压组(10.7%,16/56)无统计学差异(P>0.05)。两组均无手术死亡病例及严重后遗症。结论 PTN病人MVD中出现的困难减压并不是影响MVD疗效的决定性因素,只要术中处理得当,困难减压病人术后也可以取得很好的疗效。术前应熟悉和掌握常见的困难减压的应对方法,并且秉持适可而止的理念,减少手术并发症,可进一步提高手术疗效。  相似文献   
53.
Prostate growth seems to be influenced by paracrine factors like endothelin-1 (ET-1), originating from the microvascular endothelium. Recently, we reported on the first isolation and primary culture of microvascular endothelial cells (HPEC) derived from tissue of human benign prostatic hyperplasia (BPH). Therefore, direct investigation of growth factor secretion by HPEC is now possible.

BPH tissue was cut into small cubes and gently squeezed after incubation with dispase. HPEC were cultured from the resulting cell suspension after a stepwise selection by use of superparamagnetic beads coated with antibodies against endothelial specific antigens. HPEC were characterized by flow cytometry. After the incubation of HPEC either with vascular endothelial growth factor (VEGF), tumor necrosis factor α (TNF-α), or adenosine triphosphate (ATP), the secretion of ET-1 was measured by ELISA.

HPEC showed a typical endothelial morphology. They were positive for von Willebrand factor and CD31. The ET-1 secretion of HPEC was inhibited by VEGF, but was unaffected by TNF-α or ATP. Furthermore, histochemistry revealed that in vivo microvascular endothelial cells were negative for ET-1. Because of the suppression by the widespread VEGF, it is unlikely that ET-1 from the microvascular endothelium acts as a growth factor in human BPH.  相似文献   
54.
目的初步探讨显微血管减压术中单纯应用涤纶垫棉治疗基底动脉压迫所致三叉神经痛的临床疗效。方法回顾性分析2012年1月至2019年12月陆军军医大学大坪医院神经外科收治的31例基底动脉压迫引发三叉神经痛患者的临床资料。31例患者在显微血管减压术中均单纯使用涤纶垫棉作为减压材料,且未使用其他减压方式。手术采用经乙状窦后入路,于脑干和责任动脉之间放置涤纶垫棉实现减压。采用巴罗神经学研究所(BNI)提出的疼痛分级评估手术效果。结果31例三叉神经痛患者中,27例(87.1%)术后疼痛即刻完全缓解(BNI分级Ⅰ级),3例在术后3个月内完全缓解(BNI分级Ⅰ级),1例疼痛部分缓解(BNI分级Ⅲ级)。5例(16.1%)患者术后出现面部感觉减退,其中3例自愈;1例患者出现渐进性听力下降。31例患者的随访时间为6~85个月(中位时间为40个月),随访期间有4例(12.9%)复发(BNI分级Ⅳ~Ⅴ级),其中2例再次接受手术治疗,另外2例采用立体定向放射治疗配合药物治疗可部分控制面部疼痛。结论显微血管减压术中单纯应用涤纶垫棉治疗基底动脉所致三叉神经痛的术后即刻效果显著,但其复发率及并发症的发生率较高。  相似文献   
55.
 目的:探讨葡萄糖调节蛋白78(GRP78)引发大鼠肝肺综合征(HPS)肺微血管重构的机制。方法:Wistar大鼠被随机分为4周组、6周组和8周组3个时点,采用复合致病因素法制备大鼠肝硬化合并HPS模型,并设标准饮食的正常大鼠作为对照组。免疫组化染色法观察肺组织GRP78、Ⅷ因子相关抗原(FⅧ-RAg)C/EBP 同源蛋白(CHOP)/生长阻滞及DNA损伤诱导蛋白153(GADD153)、caspase-12、Bcl-2和核因子(nuclear factor,NF)-κB的表达。RT-PCR和Western blotting法检测肺组织血管内皮生长因子(VEGF) mRNA和蛋白表达水平。结果:模型组动物肺组织中GRP78、FⅧ-RAg及VEGF蛋白的表达随HPS进展逐步增高,CHOP/GADD153及caspase-12的表达随HPS进展逐步降低,Bcl-2和NF-κB随病程进展表达逐渐增加,NF-κB尤以胞核表达增高明显。GRP78与FⅧ-RAg及VEGF蛋白水平呈明显正相关(P<0.01),而与CHOP/GADD153及caspase-12的表达呈明显负相关(P<0.01)。在各时点,模型组动物肺组织GRP78和FⅧ-RAg显著高于正常对照组;VEGF蛋白和mRNA均显著高于正常对照组;而CHOP/GADD153及caspase-12 的表达均低于正常对照组(P<0.05)。结论:GRP78可能通过促进血管内皮细胞增殖和抑制其凋亡,促进肺微血管重构,导致HPS的发病。  相似文献   
56.
目的 明确两种微血管内皮细胞(MVECs)糖链表达的特点。 方法 复苏冻存的大鼠空肠黏膜MVECs;取3日龄SPF仔猪肺组织,采用胶原酶消化法和差速贴壁法分离培养猪肺MVECs;采用凝集素细胞化学方法,检测刀豆凝集素(Con A)、菜豆红细胞凝集素(PHA-E)、蓖麻凝集素Ⅰ(RCA-Ⅰ)、番茄凝集素(LEL)、黑接骨木凝集素(SNA)、荆豆凝集素Ⅰ(UEA-Ⅰ)、麦胚凝集素(WGA)和双花扁豆凝集素(DBA)共8种凝集素在两种MVECs的染色情况。 结果 大鼠空肠黏膜MVECs对Con A、WGA和LEL呈强阳性着色,PHA-E、SNA和RCA-Ⅰ呈中等阳性着色,DBA呈弱阳性着色,UEA-Ⅰ呈阴性着色;猪肺MVECs对Con A和PHA-E呈强阳性着色,RCA-Ⅰ呈中等阳性着色,LEL和SNA呈弱阳性着色,UEA-Ⅰ、WGA和DBA呈阴性着色。 结论 两种MVECs的糖链表达具有显著异质性,大鼠空肠黏膜MVECs和猪肺MVECs均不同水平地表达甘露糖、半乳糖、1, 3-N-乙酰葡糖胺和唾液酸,N-乙酰葡糖胺和N-乙酰半乳糖胺表达于前者不表达于后者,岩藻糖在两者均不表达。  相似文献   
57.
58.

OBJECTIVE:

To evaluate the horizontal mattress technique in microvascular anastomosis for size-mismatched vessels.

METHODS:

The present study involved cadaveric simulation using size-mismatched (1.5:1) Thiel-embalmed cadaveric arteries. The authors performed horizontal mattress anastomoses using 9-0 nylon suture and recorded the procedure. Vessel patency was evaluated by saline infusion. Vessels were cut open and photographed; histological slides were prepared and stained with hematoxylin and eosin.

RESULTS:

Four anastomoses were performed. Vessels were found to be patent in all cases, with grade 0 leaks. Intima-on-intima apposition with no intraluminal exposure of muscularis nor adventitia were observed.

CONCLUSION:

The present cadaveric study supports the technical feasibility of using horizontal mattress sutures in size-mismatched end-toend anastomoses.  相似文献   
59.

BACKGROUND:

Fluid management of the surgical patient has undergone a paradigm shift over the past decade. A change from ‘wet’ to ‘dry’ to a ‘goal-directed’ approach has been witnessed. The fluid management of patients undergoing free flap reconstruction is particularly challenging. This is typically a long operation with minimal surgical stimulation, and hypotension often ensues. The use of vasopressors in these cases is contraindicated to maintain adequate flow to the flap. Hypotension is often treated with intravenous fluid boluses. However, aggressive fluid administration to maintain adequate blood pressure can result in flap edema, venous engorgement and, ultimately, flap loss.

OBJECTIVE:

The primary objective of the present study was to determine whether goal-directed fluid therapy, titrated to maintain stroke volume variation ≤13%, with the use of an arterial pulse contour device results in improved postoperative cardiac index (CI) and stroke volume index (SVI) with reduced amounts of intravenous fluid. The primary end points studied were CI, SVI and cumulative crystalloid/colloid administration.

METHODS:

Twenty female patients undergoing simultaneous microvascular free flap reconstruction immediately following mastectomy were studied. Preoperative and intraoperative care were standardized. Each patient received intra-arterial blood pressure monitoring. In all patients, cardiac output measurement occurred throughout the intraoperative period using the arterial pulse contour device. Control patients had their fluid administered at the discretion of the anesthesiologist (blinded to results from the cardiac output device). Patients in the intervention group had a baseline crystalloid infusion of 5 mL/kg/h, with intravenous colloid boluses to maintain a stroke volume variation ≤13%.

RESULTS:

There was no difference in heart rate or mean arterial pressure between groups at the end of the operation. However, at the end of the operation, the intervention group had significantly higher mean (± SD) CI (3.8±0.8 L/min/m2 versus 3.0±0.5 L/min/m2; P=0.02) and SVI (51.4±2.4 mL/m2 versus 43.3±2.3 mL/m2; P=0.03). This improved CI and SVI was achieved with similar amounts of administered intraoperative fluid (5.8±0.5 mL/kg/h versus 5.0±0.7 mL/kg/h, control versus intervention). The intervention group required less postoperative fluid resuscitation during the early postoperative period (total fluid administered from end of operation to midnight of the operative day, 6.4±1.9 mL/kg/h versus 10.2±3.3 mL/kg/h, intervention versus control, respectively, P<0.01).

DISCUSSION:

Goal-directed fluid therapy using minimally invasive cardiac output monitoring resulted in improved end-operative hemodynamics, with less ‘rescue’ fluid administration during the perioperative period.  相似文献   
60.
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