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81.
目的:研究NOS、O2-·和Ca2+在犬高动力型肺动脉高压形成中的意义,控讨O2-·、[Ca2+]i在L一精氨酸→NO通路上的调节作用。方法:6只高动力型肺动脉高压模型犬,检测肺组织NOS活性,丙二醛(MDA)含量及总钙含量。结果:与正常比较,肺高压时,肺组织NOS活性较正常明显降低(P<0.01),MDA、[Ca2+]i;含量明显升高(P<0.05),肺组织NOS与平均肺动脉压(MPAP)、肺血管阻力(PVR)、[Ca2+]i及MDA呈明显负相关。结论:NO作用减弱在肺高压形成中与限速酶NOS活性降低密切相关,O2·和[Ca2+];共同介导肺高压过程。 相似文献
82.
Reliability of Doppler color flow mapping in the identification and localization of multiple ventricular septal defects 总被引:1,自引:0,他引:1
Spevak PJ Mandell VS Colan SD Van Der Velde ME Jonas RA Lock JE Sanders SP 《Echocardiography (Mount Kisco, N.Y.)》1993,10(6):573-581
The purpose of this study was to compare Doppler color flow mapping with angiography and surgical observation for detection of multiple ventricular septal defects (VSDs). Only patients with elevated pulmonary ventricular pressure were included. Among 137 patients with VSDs, 38 multiple defects were identified in 25 patients echocardiographically, 34 multiple defects in 24 patients angiographically, and 21 multiple defects in 17 patients surgically. Using surgical observation as the reference standard, the sensitivity of echocardiography for identifying patients with multiple VSDs was 17 of 17 (100%) and for angiography 15 of 17 (88%). The sensitivity of echocardiography for identifying all multiple VSDs seen at operation was 19 of 21 (90%) and of angiography was also 19 of 21 (90%). In many patients, use of both techniques may no longer be necessary. 相似文献
83.
The purpose of this study was to evaluate the stability of the arterial PCO2 (PaCO2) to end-tidal PCO2 (PETCO2) partial pressure difference (Pa-ETCO2) during surgery using PETCO2 monitoring, in children with congenital heart disease (CHD). Forty children with CHD were studied: ten children with no interchamber communication and normal pulmonary blood flow (PBF) (normal group); ten acyanotic children with increased PBF (acyanotic-shunting group); ten cyanotic children with mixing type lesions and normal or increased PBF (mixing group), and ten cyanotic children with right-to-left intracardiac shunts demonstrating decreased and variable PBF (cyanotic-shunting group). Simultaneous PaCO2 recordings and PETCO2 measurements were obtained for each patient during five intraoperative events: (1) control time, arterial line placement under anaesthesia; (2) time 1, patient preparation; (3) time 2, immediately after sternotomy; (4) time 3, after heparin administration; and (5) time 4, immediately after aortic cannulation. Initially, cyanotic children demonstrated a greater Pa-ETCO2 compared with acyanotic children (P less than 0.05). There was no difference in the Pa-ETCO2 over time in the control, acyanotic-shunting, or mixing groups. The Pa-ETCO2 in the children with cyanotic-shunting lesions at times 2 and 3 was greater (P less than 0.05) than at their control times. We conclude that the Pa-ETCO2 of children with acyanotic-shunting and mixing congenital heart lesions is stable intraoperatively, although patients with mixing congenital heart lesions may demonstrate large individual variations. In children with cyanotic-shunting congenital heart lesions, the Pa-ETCO2 is not stable. The PETCO2 cannot be used during surgery to estimate reliably the PaCO2 in children with cyanotic CHD. 相似文献
84.
We report here a 54-year-old man with an aneurysm arising on a cervical anterior radiculomedullary artery. The aneurysm ruptured
just after vertebral angiography for a vascular anomaly of the brain, and it appeared to be fusiform, with thrombosis following
angiography. Considering the sequential radiological studies and clinical course, it was assumed to be a dissecting aneurysm
caused by the angiography. MRI showed severe swelling of the cervical spinal cord and an infarct in the territory of the anterior
spinal artery. The mechanism of this rare complication is discussed.
Received: 29 March 1999 Accepted: 18 August 1999 相似文献
85.
神经管发育不良患儿及其核心家庭MTHFR基因A1298C多态性分布的研究 总被引:1,自引:0,他引:1
目的 通过对神经管发育不良 (NDTs)患儿及核心家庭MTHFR基因A1 2 98位点多态性分布的研究 ,探讨该基因多态性与NDTs之间的关系。方法 2 0 0 0年 9月~ 2 0 0 2年 3月 ,40例 3~ 1 5岁NDTs患儿 (男 2 8例 ,女 1 2例 )及其中 2 6个核心家庭进行研究。应用聚合酶链反应 限制性片段长度多态性分析 (PCR RFLP)技术 ,分析MTHFR基因第 1 2 98位核苷酸基因型 (野生型、杂合型、突变纯合型 )的分布情况 ;并对 2 6个核心家庭进行以父母为对照的病例对照研究 ,计算传递失衡指数 (TDT)及基于单体型的单体型相对危险度 (HHRR)。结果 NDTs患儿、核心家庭与正常对照中均未发现纯合突变。基因型构成比采用 χ2 检验 ,NDTs患儿及患儿母亲野生型分别占 1 7.50 % ,1 1 .54 % ,杂合型分别占 82 .50 % ,88.46 % ,与正常对照之间差异无显著性意义 (分别为P >0 .2 5 ;P>0 .90 )。患儿父亲野生型占 30 .77% ,杂合突变型占 69.2 3 % ,低于正常对照 (P <0 .0 5)。等位基因频率比较采用u检验 ,患儿为 41 .2 5 % ,与对照间差异无显著性意义 (P >0 .0 5) ;患儿父母分别为69 .2 3 % ,88.46 % ,均高于正常对照 (P <0 .0 1 )。核心家庭分析结果 :TDT(χ2 ) =0 .36 ,P >0 .0 5 ;HHRR(χ2 ) =0 .369,P >0 .0 5。结论 MTHFR基因第 1 2 相似文献
86.
胎儿心律失常的临床意义及预后的研究 总被引:1,自引:0,他引:1
目的 总结胎儿心律失常原因,进一步探讨其临床意义及对胎儿预后的影响。方法 采用回顾性分析方法,对26例胎儿心律失常孕妇的情况、胎儿心律失常的临床表现、诊断方法及长期随诊结果进行总结。结果 胎儿心律失常的发生率为0.2%。26例胎儿心律失常中,3例为胎儿心动过速(11.5%),4例为胎儿心动过缓(15.4%),19例为不规则胎儿心律(73.1%);胎儿心律失常平均诊断孕周为35托周(15~41^ 1周)。26例中22例为产前胎心听诊时发现胎儿心律失常;1例为妊娠15周超声检查时发现胎儿心律失常;3例胎心监测发现胎儿心律失常。17例产前进行了胎儿超声心动检查,心脏结构未见异常,其中6例胎儿超声心动检查提示胎儿房性早搏,占35.3%,余未见异常。产后新生儿均存活,随诊24例(92.3%),16例新生儿进行了超声心动检查,其中2例诊断为先天性心脏病,均为房间膈缺损。先天性心脏病新生儿在心律失常胎儿中发生率为7.7%。结论 大多数心律失常的胎儿预后是好的,心脏畸形的发生率很低。对于持续性心率慢的胎儿,需注意心脏结构异常的存在;对于心律失常胎儿的处理采用期待疗法,根据产科指征决定终止妊娠的方式。 相似文献
87.
小儿先天性左向右分流型心脏病的介入治疗 总被引:2,自引:2,他引:2
目的 评价应用Amplatzer封堵器进行介入治疗小儿先天性心脏病的效果、安全性。方法 超声心动图确诊的动脉导管未闭 (PDA)、房间隔缺损 (ASD)及膜部室间隔缺损 (膜部VSD)患者 4 9例 ,在透视或 /和经胸超声心动图 (TTE)指引下置入Amplatzer封堵器 ,术后 2 4小时 ,1、3、6、12个月及以后每年分别TTE、ECG和X线胸片检查评价治疗效果。结果 16例ASD球囊测量缺损伸展径为 13~ 2 8(平均 19 3± 4 9)mm ,选择封堵器直径 13~ 30 (平均 2 0 6± 5 1)mm ;2 5例PDA造影测量PDA最窄处直径为 2~ 7 7(平均 3 9± 1 5 )mm ,选择封堵器直径 4~ 12 (平均 6 6± 1 9)mm ;8例膜部VSD造影测量VSD直径 3 4~ 8(平均 4 7± 2 3)mm ,选择封堵器直径 6~ 10 (平均 7 8±1 7)mm。技术成功率为 10 0 % ,术中未发生任何并发症 ,无急诊手术病例。术后即刻造影或TTE显示 10例存在残余分流 ,3个月TTE示所有病例无残余分流和再通 ,心室内径均有不同程度的缩小 ,肺动脉压下降。结论 应用Amplatzer封堵器介入治疗小儿先天性心脏病 ,具有操作简单、安全、损伤小、成功率高等优点 ,适合于儿童继发孔型ASD、各种类型的PDA及膜部VSD的介入治疗 相似文献
88.
89.
OBJECTIVE—To review the outcomes of 193 fetuses with cardiac abnormalities detected by echocardiography.METHODS—A total of 422 fetuses between 16 and 41 gestational weeks, referred to paediatric cardiologists for detailed echocardiography, were included in this study.RESULTS—Structural heart defects were found in 55 (28%), isolated arrhythmia in 105 (54%), and other non-structural abnormalities (dilated cardiomyopathy, hypertrophic cardiomyopathy, aneurysm of the foramen ovale, isolated pericardial effusion or echogenic foci) in 33 (17%) of 193 fetuses. Total mortality was 26%. The prognosis was poor in fetuses with structural heart defects; 37 of 55 cases (67%) died in utero or postnatally. Chromosomal abnormality was associated with structural heart defect in 38% of fetuses, of whom 38% died. Among fetuses with isolated arrhythmia survival was 95%. Poor outcome was associated with complete heart block (n=14) in 2 (14%) fetuses with hydrops and heart rate of less than 55 per minute, and with supraventricular tachycardia (n=21) in three (14%) neonates delivered prematurely at a mean gestational age of 33 weeks. Furthermore, nine of 12 fetuses (75%) with structural heart defects and arrhythmia died. Among fetuses with non-structural cardiac abnormalities, survival was 73%. Poor outcome was evident in fetuses with dilated cardiomyopathy in eight of 13 (62%) and with hypertrophic cardiomyopathy in one of eight (13%) of cases.CONCLUSIONS—Factors associated with a poor prognosis were: structural heart defect associated with chromosomal abnormality or arrhythmia, congestive heart failure associated with supraventricular tachycardia or complete heart block, especially if delivery occurs preterm; and fetal hydrops with congestive heart failure and atrioventricular valve regurgitation. 相似文献
90.
恶性肿瘤累及颈动脉的外科处理 总被引:2,自引:1,他引:2
为探讨头颈部恶性肿瘤侵犯颈动脉的外科治疗,对5例喉癌或下咽癌颈淋巴结转移累及一侧颈动脉病人,术前经CT或B超检查,3例经术前体外颈动脉压迫训练合格后手术切除受累段颈总动脉,2例系术中损伤颈总动脉后紧急切除受轻动脉。其中1例即刻行断端吻合,5例术中,术后均无明显脑缺血表现,3例术后随访2年以上健在,2例尚在随访中。 相似文献