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1.
Sinus venosus atrial septal defect (SV‐ASD) usually coexists with partial anomalous pulmonary vein connection (PAPVC). It is a difficult diagnosis in transthoracic echocardiography (TTE) due to eccentric position of defects. We present a rare case of atypical anatomical variation in PAPVC, which was never described before. Two right pulmonary veins drained into superior vena cava, which overrode SV‐ASD and interatrial septum, a third pulmonary vein into the right atrium. Complete diagnosis could not be set after TTE, nor transesophageal echocardiography, whereas angio‐CT was finally conclusive. This diagnostic approach allowed the surgical planning.  相似文献   
2.
Idiopathic myointimal hyperplasia of mesenteric veins (IMHMV) is a rare and poorly understood ischemic colitis that occurs in the rectosigmoid colon of predominantly young, previously healthy, male patients. A 76‐year‐old Japanese man presented to our hospital with a 1‐year history of worsening diarrhea, lower abdominal pain, and weight loss (−6 kg). Laboratory evaluation revealed white blood cell count of 13 200/μL, C‐reactive protein level of 2.0 mg/dL (normal range, 0.0–0.3), and negative results for stool culture (including Clostridium difficile). Colonoscopy showed circumferential and edematous narrowing of the sigmoid colon with deep longitude ulceration. Biopsy was done and examination of the specimen demonstrated no specific ischemia. The patient was treated with bowel rest, antibiotics, and i.v. fluids; however, his symptoms worsened. Finally, sigmoidectomy was carried out. Histological examination demonstrated significant myointimal hyperplasia of mesenteric veins leading to thickening and stenosis of the venous lumen. Therefore, the final diagnosis was IMHMV. Three months following sigmoidectomy, he was asymptomatic.  相似文献   
3.
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation.  相似文献   
4.
目的 探讨磁共振脑表面成像技术在矢状窦旁腩膜瘤手术中的应用价值.方法 分析本院经头颅CT及MRI诊断为矢状窦旁脑膜瘤,利用显微手术技术切除并经病理证实的的22例患者;术前均运用磁共振脑表面成像技术评估与肿瘤关系密切的脑表面回流静脉情况.术中根据成像结果有目的 地保护重要的回流静脉,对比患者手术前后神经功能恢复状况,并进行随访来评价手术效果.结果 22例患者的术前磁共振脑表面成像中脑表面回流静脉与术中所见高度一致.术后患者恢复良好,未出现与静脉损伤相关的并发症.结论 磁共振脑表面成像技术能在术前明确矢状窦旁脑膜瘤与脑表面回流静脉之间关系,可在术前对患者肿瘤表面脑回流静脉做出正确的评估,对脑表面重要回流静脉的保护提供了准确的影像学依据,对患者神经功能的保护及术后恢复起到重要作用.  相似文献   
5.
氯胺酮对脂多糖诱导下人脐静脉内皮细胞活化的影响   总被引:9,自引:0,他引:9  
目的 观察氯胺酮和N-甲基-D-天门冬氨酸(NMDA)受体非竞争性拮抗剂MK-801对脂多糖(LPS)刺激下人脐静脉内皮细胞(HUVECs)胞间粘附分子-1(ICAM-1)表达及核因子-kappa B(NF-kB)易位表达的影响。方法 采用Jaffe方法培养的HUVECs随机分为10组:对照组(C组,RPMI-1640),LPS组(L组,LPS1μg/ml),氯胺酮组(K组,依浓度不同分为KⅠ、KⅡ、KⅢ、KⅣ亚组,即氯胺酮12.5、25.0、100、300μmol/L LPS1μg/ml),MK-801组(M组,依浓度不同分为MⅠ、MⅡ、MⅢ、MⅣ亚组,即MK-801 1.25、2.50、10、30μmol/L LPS1μg/ml)。在37℃、5%CO_2中孵育18h后,用流式细胞仪检测ICAM-1的表达阳性率。NF-kB易位表达的测定分组处理同上,在LPS1μg/ml刺激2h后,用免疫组化(SP)方法测定内皮细胞中NF-kB p65亚基的表达。结果 KⅡ、KⅢ、KⅣ亚组可抑制LPS作用下HUVECs表面ICAM-1的表达和细胞内部NF-kB的易位表达(P<0.05),且两者的变化呈正相关(r=0.985,P<0.01)。M组各亚组对LPS作用后HUVECs表面ICAM-1的表达和NF-kB的易位表达无明显影响(P>0.05)。结论 氯胺酮对炎症反应中内皮细胞的活化具有抑制作用,但并非通过NMDA受体途径。  相似文献   
6.
本文通过分析50例脑动静脉畸形(AVM)的全脑数字减影血管造影(DSA)资料及手术探查结果,探讨AVM的深、浅及供血、引流血管数量与出血发生率的关系。经统计比较发现:深部较浅部AVM出血率高;供应动脉条数多于导出静脉条数者及仅有单条导出静脉出血率最高,并与其他组有显著性差异(P<0.05、P<0.01)。因此,我们认为:在临床工作中对这些AVM患者应给予足够的重视。  相似文献   
7.
应用脐静脉灌注冲洗人胎儿肝脏,胰蛋白酶消化后经光镜及扫描电镜观察,证实可获得纯度为90%以上的肝实质细胞,培养上清液可测出胎甲蛋白活性,证明胎肝细胞具有生物学活性,为应用人肝细胞培养进行生理生化及药理方面的实验研究,提供一种新的获取人肝细胞的方法.  相似文献   
8.
射频闭合与传统剥脱术治疗下肢静脉曲张的对照研究   总被引:7,自引:0,他引:7  
目的评价射频闭合(radiofrequency endovenous obliteration,RFO)的疗效。方法 56例(56条肢体)大隐静脉曲张患者随机分为两组,每组28例。RFO组利用射频能量使大隐静脉全程闭合,静脉剥脱组用传统方法高位结扎剥脱大隐静脉。两组病例小腿散在的曲张浅静脉均采用点式剥脱处理。比较两组病例的切口数、术后疼痛、平均住院日和短期疗效等情况。结果 RFO组平均切口少、术肢疼痛轻、无皮下血肿,术后平均住院日(2.50±1.00)d。静脉剥脱组的术后平均住院日(4.14±0.85)d。结论 RFO闭合大隐静脉具有创伤小、恢复快、腿部少留瘢痕等优点,是一种可部分替代传统大隐静脉高位结扎剥脱术的有效方法。  相似文献   
9.
Jan Erik Hardebo  M.D. 《Headache》1994,34(3):125-131
SYNOPSIS
A large body of evidence points to an inflammatory process in the cavernous sinus and tributary veins as being primarily responsible for cluster headaches. The inflammation obliterates the venous outflow from the cavernous sinus on one side and injures the through-running sympathetic fibers to the eye, upper eye lid, forehead skin, and the intracranial internal carotid artery and its branches. The active period ends when the inflammation is suppressed and the sympathetic fibers partially or fully recover. Evidence is presented that the symptoms suggestive of an enhanced parasympathetic activity during attacks may alternatively be explained as local pain fiber activation or a stasis in the outflow from the cavernous sinus. Vasodilator agents like nitroglycerin induce an attack by enhancing the venous load on the cavernous sinus. Constriction of the proximal intracranial internal carotid artery, spontaneously induced by tressful pain activation of the perivascular sympathetic nerves, or by exogenous administration of serotonin 1 D-like receptor agonists or oxygen, terminates the venous load and thus the pain and associated symptoms.  相似文献   
10.
We investigated the relationship between esophageal varices and the collaterals by endoscopy and endoscopic ultrasound (20 MHz ultrasonic miniprobe; UMP). Moreover, we investigated the correlation between the collaterals around the esophagus and recurrence of esophageal varices in patients with portal hypertension who had undergone EIS. The collaterals were divided into two groups: peri‐esophageal collateral veins (peri‐ECVs) and para‐esophageal collateral veins (para‐ECVs). These were scored as mild or severe according to the stage of development. According to endoscopy, the varix form was significantly larger in severe the peri‐ECVs group than in mild the peri‐ECVs group. The prevalence of perforating veins increased according to the varix form. With regard to variceal recurrence, in patients with variceal recurrences, UMP findings included a significantly higher incidence of severe peri‐ECVs, a significantly larger diameter of perforating veins compared with patients without recurrence. In conclusion, the presence of severe peri‐ECVs and large perforating veins in the esophageal wall strongly correlates with occurrence and recurrence of esophageal varices in patients with portal hypertension. An understanding of these UMP abnormalities on the basis of hemodynamics around the esophagus is thought to be important for management of esophageal varices in patients with portal hypertension.  相似文献   
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