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991.
We describe the case of a pregnant woman with idiopathic pulmonary arterial hypertension, a responder in right heart catheterization, followed since the first trimester in outpatient consultations, admitted to hospital at 23 weeks gestation. She was treated with inhaled iloprost until delivery (at 34 weeks gestation) and continuous infusion of iloprost throughout the perioperative period and following days. This line of therapy has proved efficacious in previous cases. The authors present echocardiographic images that document acute changes in ventricular synchrony during inhalation of iloprost.  相似文献   
992.
We present a case of intermittent cessation of blood flow through stent struts during systole, with normal flow during diastole in the previously stented ostial vein graft. After reviewing the initial procedure, we discovered that the operator had difficulty in positioning the stent. After stent deployment, the ostial stent was malpositioned and was protruding more than 50% into the aorta. During systole, the contrast in the stent struts, which are situated in the aorta, was being washed off by systolic blood flow, while in the diastole, the flow of contrast was normal. This is the first case report of this observation with a brief review.  相似文献   
993.
目的:探讨急性低氧运动对血液流变性和红细胞形态的影响以及补充电解质饮料的干预效果。方法:受试者为8名健康成年男性,均进行两次实验。第1次为急性低氧运动加补充电解质饮料(运动前和运动中)实验,第2次为急性低氧运动不补充任何液体实验,两次实验间隔1周。受试者以70%最大摄氧量(VO2max)强度在低氧环境(O2浓度为15.5%,环境温度为20℃,湿度为55%)下进行1小时的功率自行车运动。分别测定受试者运动前、后的血液流变学指标并观察其红细胞形态的变化。结果:不补液情况下,受试者运动后的血液粘度、红细胞压积及红细胞刚性指数显著增加(P<0.01)。红细胞形态由双凹圆盘形变为一面凸、一面凹的草帽形。运动前和运动中补充电解质饮料,受试者运动后的各项血液流变学指标与运动前相比变化均不显著(P>0.05),且运动后红细胞形态未见明显变化。结论:运动前和运动中补充电解质饮料可缓解急性低氧运动对机体血液流变性产生的不良影响。  相似文献   
994.
目的:观察福辛普利晚期预处理对缺氧复氧心室肌细胞Na /Ca2 交换电流的影响。方法:应用全细胞膜片钳方法,记录观察酶解的成年豚鼠心室肌细胞Na /Ca2 交换电流在缺氧复氧期的变化。结果:缺氧复氧明显增加心肌Na /Ca2 交换电流,在-100mV和 60mV时较对照组分别增加41.05%及32.75%,福辛普利预处理后可明显抑制缺氧复氧心肌Na /Ca2 交换电流,在-100mV和 60mV时分别减少17.90%及14.20%,有助于减少钙内流,减轻钙超载。结论:福辛普利预处理可抑制缺氧复氧心肌Na /Ca2 交换电流逆向转运。  相似文献   
995.
目的探讨用游离自体腹白线片修补急性十二指肠溃疡穿孔的应用价值。方法从2006年1月至2006年7月对13例用自体腹白线片修补急性十二指肠溃疡穿孔的病人的临床资料和随访情况进行回顾性分析,其中2例穿孔大于2cm2,平均手术时间60分钟,平均失血量20ml,平均住院天数9±1天。结果游离自体腹白线片修补急性十二指肠溃疡穿孔13例均痊愈出院。随访15天至6个月,无手术并发症。结论本方法操作较简单、安全、效果好,其适应症广,是一种可行的新方法。  相似文献   
996.
Birnie  D.  H.  Vickers  L.  E.  Hillis  W.  S.  杨海涛 《世界核心医学期刊文摘》2006,2(1):49-50
目的:探讨抗人热休克蛋白60或抗分枝杆菌热休克蛋白65抗体是否能够预测因急性心源性胸痛入院的患者一年预后不良。设计:前瞻性观察研究。地点:教学医院。患者:连续588例急诊收治的疑似急性心源性胸痛患者。主要观察指标:测定入院后晨起血样的抗人热休克蛋白60和抗分枝杆菌热休克蛋白65效价。出院后终点为冠心病死亡、非致死性心肌梗死、冠状动脉搭桥术、经皮穿刺腔内冠状动脉成形术、血管造影或因心脏缺血性胸痛加重再次入院。  相似文献   
997.
Cigarette smoking may alter bronchial inflammation in asthma. Multicolour immunohistofluorescent examination on bronchial cryosections was used to examine bronchial inflammatory cell infiltrate in patients with occupational asthma. Monoclonal antibodies to CD3, CD4, CD8, T-cell receptor-delta1, CD68 and human leukocyte antigen-DR were combined to identify T-cell subsets and macrophages in bronchial biopsies from 20 workers with occupational asthma (12 smokers and eight nonsmokers), 15 healthy workers (seven smokers and eight nonsmokers) and 10 nonsmoking, nonexposed controls. The increased subepithelial CD4+ T-cell density in nonsmoking asthmatics was not present in smoking asthmatics, who had the lowest CD4+ T-cell density of all groups. The decreased subepithelial CD4+ and CD8+ T-cell density correlated with a reduction in lung function, as measured by percentage predicted forced expiratory volume in one second, in smoking asthmatics only. Although smoking asthmatics had a significantly increased number of intraepithelial CD8+ T-cells and macrophages compared with nonsmoking asthmatics, the proportion of gammadelta-T-cells was significantly decreased in both asthmatic groups. Smoking asthmatics had a distinctly different distribution of T-cell subsets compared with nonsmoking asthmatics. The accumulation of subepithelial CD4+ T-cells, which was observed in nonsmoking asthmatics, appeared to be inhibited in smoking asthmatics, suggesting a smoking-induced bronchial immune modulation, at least in occupational asthma in the aluminium industry.  相似文献   
998.
OBJECTIVE: Optimal timing for CABG surgery after myocardial infarction (MI) remains controversial. We examined the influence of patient age and time elapsed between MI and isolated CABG surgery on operative mortality. METHODS: Perioperative data of 13,545 patients who underwent isolated CABG surgery from 1991 to 2005 were reviewed. A previous MI was found in 7219 patients, classified among groups A-E whether they underwent surgery less than 6h (A, n=26), between 6 and 24h (B, n=51), between 1 and 7 days (C, n=313), between 8 and 30 days (D, n=917), or more than 30 days (E, n=5912) after the event. Crude percentages and odds ratio estimates of operative mortality were calculated. RESULTS: In patients who had no history of MI, the mortality rate was 1.7%, while it was, respectively, 19.2, 9.8, 8.6, 3.2, and 2.4% in patients from groups A to E. Among 6589 patients over 65 years of age, 3027 had no history of MI. Their mortality was 2.4%, compared to, respectively, 35.7, 13.8, 11.3, 5.1, and 3.9% for those belonging to groups A-E. Overall odds ratio estimates of operative mortality were 3.92 (p=0.19), 5.08 (p=0.002), 4.33 (p=0.0001), 1.50 (p=0.08), and 1.18 (p=0.24) for groups A-E, respectively. CONCLUSIONS: Operative mortality is not influenced by a history of MI sustained more than 30 days prior to isolated CABG surgery, but is highly and most significantly increased between 6h and 1 week after MI, especially in older patients. That critical period should be avoided whenever possible.  相似文献   
999.
It is well known that migraine has a strong genetic component, although the type and number of genes involved remains unclear. There is evidence to suggest that serotonin-related genes may be involved in the pathogenesis of migraine. To investigate whether the 5-HT1A receptor gene contributes to the risk of migraine we performed an association study of C-1019G promoter polymorphism of the gene in 102 migraineurs and 93 controls. Subjects were of Han Chinese origin. No significant differences in allele (P=0.82) or genotype frequencies (P=0.71) were seen in migraineurs compared with the controls. When migraine with aura, without aura, with family history, without family history were analyzed separately, the frequencies did not vary significantly. Our results suggest that C-1019G in 5-HT1A is not a major genetic risk factor for migraine.  相似文献   
1000.
OBJECTIVE: This study investigated auditory involuntary and voluntary attention in children aged 6-8, 10-12 and young adults. The strength of distracting stimuli (20% and 5% pitch changes) and the amount of allocation of attention were varied. METHODS: In an auditory distraction paradigm event-related potentials (ERPs) and behavioral data were measured from subjects either performing a sound duration discrimination task or watching a silent video. RESULTS: Pitch changed sounds caused prolonged reaction times and decreased hit rates in all age groups. Larger distractors (20%) caused stronger distraction in children, but not in adults. The amplitudes of mismatch negativity (MMN), P3a, and reorienting negativity (RON) were modulated by age and by voluntary attention. P3a was additionally affected by distractor strength. Maturational changes were also observed in the amplitudes of P1 (decreasing with age) and N1 (increasing with age). P2-modulation by voluntary attention was opposite in young children and adults. CONCLUSIONS: Results suggest quantitative and qualitative changes in auditory voluntary and involuntary attention and distraction during development. The processing steps involved in distraction (pre-attentive change detection, attention switch, reorienting) are functional in children aged 6-8 but reveal characteristic differences to those of young adults. In general, distractibility as indicated by behavioral and ERP measures decreases from childhood to adulthood. SIGNIFICANCE: Behavioral and ERP markers for different processing stages involved in voluntary and involuntary attention reveal characteristic developmental changes from childhood to young adulthood.  相似文献   
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