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41.
We report a case of “hugging balloon” dilatation of a giant right coronary artery using two dilatation catheters, a balloon “on a wire” and a balloon “rapid exchange” systems via a single guiding catheter. The necessity of larger PTCA balloon catheter (>4.0 mm) was stressed.  相似文献   
42.
OBJECTIVES: The purpose of this prospective study was to quantitate the diagnostic value of several tachycardia features and pacing maneuvers in patients with paroxysmal supraventricular tachycardia (PSVT) in the electrophysiology laboratory. BACKGROUND: No study has prospectively compared the value of multiple diagnostic tools in a large group of patients with PSVT. METHODS: One hundred ninety-six consecutive patients who had 200 inducible sustained PSVTs during an electrophysiology procedure were included. The diagnostic values of four baseline electrophysiologic parameters, nine tachycardia features and five diagnostic pacing maneuvers were quantified. RESULTS: The only tachycardia characteristic that was diagnostic of atrioventricular (AV) nodal reentry was a septal ventriculoatrial (VA) time of <70 ms, and no pacing maneuver was diagnostic for AV nodal reentry. An increase in the VA interval with the development of a bundle branch block was the only tachycardia characteristic that was diagnostic for orthodromic tachycardia, but it occurred in only 7% of all tachycardias. An atrial-atrial-ventricular response upon cessation of ventricular overdrive pacing was diagnostic of atrial tachycardia, and this maneuver could be applied to 78% of all tachycardias. Burst ventricular pacing excluded atrial tachycardia when the tachycardia terminated without depolarization of the atrium, but the result could be obtained only in 27% of patients. CONCLUSIONS: This prospective study quantitates the diagnostic value of multiple observations and pacing maneuvers that are commonly used during PSVT in the electrophysiology laboratory. The findings demonstrate that diagnostic techniques rarely provide a diagnosis when used individually. Therefore, careful observations and multiple pacing maneuvers are often required for an accurate diagnosis during PSVT. The results of this study provide a useful reference with which new diagnostic techniques can be compared.  相似文献   
43.
Mandibuloacral dysplasia (MAD) is a phenotypically heterogeneous, rare autosomal recessive disorder characterized by mandibular and clavicular hypoplasia, acroosteolysis, delayed closure of cranial sutures, joint contractures, and mottled cutaneous pigmentation. Patients with MAD develop two patterns of lipodystrophy: type A pattern, with loss of sc fat from the extremities and normal or slight excess in the neck and truncal regions; and type B pattern, with a more generalized loss of sc fat involving the face, trunk, and extremities. Recently, affected patients from five consanguineous Italian pedigrees with partial lipodystrophy (type A) were reported to have a homozygous R527H mutation in LMNA (lamin A/C) gene. We carried out mutational analysis of LMNA in affected patients from six pedigrees. Affected patients from two pedigrees with type A lipodystrophy had the homozygous R527H mutation in LMNA. The other four affected subjects who had type B lipodystrophy did not have any mutation in the exons and splice site junctions of LMNA; RNA extracted from lymphoblasts of two of these patients also revealed normal sequence. In these four subjects, sequencing of other known genes implicated in lipodystrophies, i.e. AGPAT2, Seipin, and PPARG also revealed no substantial alterations. We conclude that MAD is a genetically and phenotypically heterogeneous disorder. Besides LMNA gene, other as yet unmapped loci could be linked to MAD.  相似文献   
44.
OBJECTIVES: We prospectively investigated the prevalence and value of this criterion for identifying a target site for ablation in patients with postinfarction ventricular tachycardia (VT). BACKGROUND: Termination of postinfarction VT by pacing with nonglobal capture identifies a critical component of the reentrant circuit. METHODS: In a consecutive series of 34 patients with prior infarction (age 67 +/- 10 years, ejection fraction 0.26 +/- 0.1) referred for radiofrequency catheter ablation, mapping was performed in the left ventricle. At sites with abnormal electrograms, pacing was performed during VT. If VT terminated with nonglobal capture during the pacing train, radiofrequency energy was delivered. RESULTS: Sixty-two VTs (cycle length 450 +/- 84 ms) were mapped and targeted for radiofrequency ablation. Concealed entrainment was present at 101 endocardial sites. Among the 101 sites, VT terminated by pacing with nonglobal capture at 5 sites (5%). At 10 additional sites in 10 patients, VT terminated by pacing with nonglobal capture, and concealed entrainment could not be documented at these sites because of reproducible termination of the VT. An application of radiofrequency energy resulted in VT termination at all 15 sites where nonglobal capture was documented and the targeted VTs were no longer inducible after ablation. CONCLUSIONS: Termination of VT by pacing with nonglobal capture can be demonstrated in approximately one third of patients with postinfarction VT and is a specific criterion for identifying a critical component of the reentrant circuit, whether or not concealed entrainment can be documented at that site.  相似文献   
45.
INTRODUCTION: The anatomic arrangement of pulmonary veins (PVs) is variable. No prior studies have quantitatively analyzed the effects of segmental ostial ablation on the PVs. The aim of this study was to determine the effect of segmental ostial radiofrequency ablation on PV anatomy in patients with atrial fibrillation (AF). METHODS AND RESULTS: Three-dimensional models of the PVs were constructed from computed tomographic (CT) scans in 58 patients with AF undergoing segmental ostial ablation to isolate the PVs and in 10 control subjects without a history of AF. CT scans were repeated approximately 4 months later. PV and left atrial dimensions were measured with digital calipers. Four separate PV ostia were present in 47 subjects; 3 ostia were present in 2 subjects; and 5 ostia were present in 9 subjects. The superior PVs had a larger ostium than the inferior PVs. Patients with AF had a larger left atrial area between the PV ostia and larger ostial diameters than the controls. Segmental ostial ablation resulted in a 1.5 +/- 3.2 mm narrowing of the ostial diameter. A 28% to 61% focal stenosis was present 7.6 +/- 2.2 mm from the ostium in 3% of 128 isolated PVs. There were no instances of symptomatic PV stenosis during a mean follow-up of 245 +/- 105 days. CONCLUSION: CT of the PVs allows identification of anatomic variants prior to catheter ablation procedures. Segmental ostial ablation results in a significant but small reduction in ostial diameter. Focal stenosis occurs infrequently and is attributable to delivery of radiofrequency energy within the PV.  相似文献   
46.
We analyzed the postoperative short- and mid-term outcomes of a series of patients with annuloaortic ectasia who underwent a modified Bentall operation in our clinic from September 2000 through March 2006. The study included 44 patients. Their average age was 53.4 +/- 14.1 years. The underlying disease was degenerative aortic aneurysm in 42 patients (95.5%) and acute aortic dissection in 2 patients (4.5%). Six patients (13.6%) had Marfan phenotype. Aortic insufficiency was moderate in 30 patients (68.2%) and severe in 14 patients (31.8%). In our modification of the Bentall technique, we completed the resection of the aortic root while leaving 5 to 10 mm of native aortic wall tissue to support the anastomosis. A long piece of Teflon felt (width, 0.5-1 cm) was laid on the annulus, and nonpledgeted 2-0 polyester sutures were passed in turn through the Teflon felt, the preserved aortic tissue, and the aortic annulus. A thin piece of Teflon felt was also used in the coronary artery reimplantation sites. Fibrin glue was routinely applied to all anastomoses. There were no intraoperative deaths. One patient died in the hospital after surgery for acute type I aortic dissection. Another patient died 1 year after the operation from prosthetic-valve endocarditis. No patient required surgical correction of excessive postoperative bleeding. Kaplan-Meier curves showed overall survival of 0.94 (95% confidence intervals, 0.9-0.99). We consider our approach an easy, effective way to minimize bleeding from the anastomoses and at the aortic root--a common challenge in aortic surgery.  相似文献   
47.
Background: Fine particulate matter (PM) air pollution is associated with numerous adverse health effects, including increased blood pressure (BP) and vascular dysfunction. Coarse PM substantially contributes to global air pollution, yet differs in characteristics from fine particles and is currently not regulated. However, the cardiovascular (CV) impacts of coarse PM exposure remain largely unknown.Objectives: Our goal was to elucidate whether coarse PM, like fine PM, is itself capable of eliciting adverse CV responses.Methods: We performed a randomized double-blind crossover study in which 32 healthy adults (25.9 ± 6.6 years of age) were exposed to concentrated ambient coarse particles (CAP; 76.2 ± 51.5 μg/m3) in a rural location and filtered air (FA) for 2 hr. We measured CV outcomes during, immediately after, and 2 hr postexposures.Results: Both systolic (mean difference = 0.32 mmHg; 95% CI: 0.05, 0.58; p = 0.021) and diastolic BP (0.27 mmHg; 95% CI: 0.003, 0.53; p = 0.05) linearly increased per 10 min of exposure during the inhalation of coarse CAP when compared with changes during FA exposure. Heart rate was on average higher (4.1 bpm; 95% CI: 3.06, 5.12; p < 0.0001) and the ratio of low-to-high frequency heart rate variability increased (0.24; 95% CI: 0.07, 0.41; p = 0.007) during coarse particle versus FA exposure. Other outcomes (brachial flow-mediated dilatation, microvascular reactive hyperemia index, aortic hemodynamics, pulse wave velocity) were not differentially altered by the exposures.Conclusions: Inhalation of coarse PM from a rural location is associated with a rapid elevation in BP and heart rate during exposure, likely due to the triggering of autonomic imbalance. These findings add mechanistic evidence supporting the biological plausibility that coarse particles could contribute to the triggering of acute CV events.Citation: Brook RD, Bard RL, Morishita M, Dvonch JT, Wang L, Yang HY, Spino C, Mukherjee B, Kaplan MJ, Yalavarthi S, Oral EA, Ajluni N, Sun Q, Brook JR, Harkema J, Rajagopalan S. 2014. Hemodynamic, autonomic, and vascular effects of exposure to coarse particulate matter air pollution from a rural location. Environ Health Perspect 122:624–630; http://dx.doi.org/10.1289/ehp.1306595  相似文献   
48.
Described herein are six cases of transverse testicular ectopia. All patients who underwent orchidopexy at the one pediatric surgical unit between October 2001 and January 2008 were evaluated. The medical records of all patients diagnosed with transverse testicular ectopia were evaluated retrospectively. Five patients (84%) were admitted with a symptomatic right inguinal hernia and empty scrotum on the left side. Only one child (16%) had left‐sided hernia and right non‐palpable testis (age ranged from 1 month to 3 years). Four patients (66%) were diagnosed in the operating theatre and the last two (33%) on inguinal ultrasound preoperatively. Magnetic resonance imaging was also performed in the last patient. Herniorrhaphy with fixation of the ectopic gonad to the opposite hemiscrotum through a transseptal incision was performed in all patients. Postoperative complications were not observed.  相似文献   
49.
EB病毒LMP1在鼻咽癌细胞系中通过NF-κB、AP-1促进IL-8分泌   总被引:1,自引:0,他引:1  
目的:探讨EB病毒LMP1分子致瘤机制,在已证实鼻咽癌细胞系中LMP1有效激活NF-κB 或AP-1的基础上,对LMP1是否通过NF-κB 或AP-1促进IL-8分泌进行探讨。方法:以稳定表达LMP1及其3种突变体,空白载体的鼻咽癌细胞系[HNE2-LMP1,NHE2-MLP1(1-185),HNE2-LMP1(1-231),HNE2-LMP1Δ187-351和HNF3-pSG5]及antisense-LMP1处理的HNF2-LMP1鼻咽癌的细胞系为材料,将IL-8报道质粒瞬时导入这些细胞系中,通过测定luciferase值以反映LMP1是否促进IL-8转录;将mut AP-1/IL-8-luc或IκB α(S32A/S36A)表达质粒导入HNE2-LMP1细胞系中,比较其IL-8报道活性,以确定LMP1是否通过AP-1或NF-κB 诱导IL-8转录;利用ELISA方法测定HNE2-LMP1,HNE2-pSG5,anti-sese-LMP1处理的HNE2-LMP1鼻咽癌细胞系中的IL-8浓度,进一步从蛋白水平上确定LMP1是否促进IL-8分泌。结果:与HNE2-pSG5相比,在HNE2-LMP1,HNE2-LMP1Δ187-351和HNE2-LMP1(1-231)细胞系中IL-8报道活性分别升高了原来水平的11.5,8.6和3.4倍,而HNE2-LMP1(1-185)对IL-8报道活性不影响。在HNE2-LMP1细胞系中IL-8蛋白水平提高了17.4倍,而antisense-LMP1则使HNE2-LMP1细胞的IL-8报道活性及蛋白水平分别下降到原来水平的18.3%和9.2%,导入mutAP-1/IL-8-luc或IκBα(S32A/S36A)的HNE2-LMP1细胞中IL-8报道活性分别下降到原有水平39%和26%,结论:鼻咽癌细胞系中LMP1可能通过NF-κAP-1促进IL-8表达。  相似文献   
50.
全国第六届口腔黏膜病学术会议纪要   总被引:1,自引:0,他引:1  
中华口腔医学会第六届全国口腔黏膜病学术会议,于2004年10月21至24日在上海隆重召开。参加大会的学术同仁150人,共收到来自全国25个省、市、自治区的论文190余篇,其中63位代表的论文在大会上进行了交流。本届会议中完成了全国第三届口腔黏膜病专业委员会的改选,选举了以周曾同教授为主任委员的新一届专业委员会,讨论并通过了“口腔扁平苔藓(萎缩型、糜烂型)疗效评价标准(试行)”,内容精彩纷呈,学术讨论气氛浓厚。  相似文献   
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