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71.
右室双部位起搏与双室同步起搏的急性血液动力学对比研究 总被引:9,自引:4,他引:9
比较右室双部位 (RV Bi)起搏和双室 (BiV)同步起搏对血液动力学的影响 ,并与右室心尖部 (RVA)、右室流出道 (RVOT)、左室基底部 (LVB)起搏相比较 ,明确双部位起搏是否优于单部位起搏。 15例患者中病窦综合征 8例、Ⅲ度房室阻滞 7例。分别行RVA、RVOT、LVB、RV Bi、BiV起搏 (VVI,6 0~ 90次 /分 ) ,测定心输出量 (CO)和心脏指数(CI)、肺毛细血管嵌顿压 (PCWP)和QRS波时限 (QRSd)。结果 :①与RVA起搏相比 ,RVOT、LVB、RV Bi、BiV起搏CI分别增加了 7.5 %、11.3%、15 .5 %和 17.2 % ,PCWP分别降低了 14.9%、10 .3%、2 1.7%和 2 0 .0 % (P均 <0 .0 1)。②RV Bi、BiV起搏较RVOT、LVB起搏的CO、CI增高而PCWP降低 (P均 <0 .0 5 )。③RV Bi与BiV起搏、RVOT与LVB起搏之间CO、CI和PCWP无显著差异。④RVOT、RV Bi、BiV起搏的QRSd(分别为 12 8± 11,111± 16 ,10 3± 13ms)较RVA起搏 (146± 18ms)时显著缩短 (P≤ 0 .0 0 1) ,而LVB起搏 (142± 15ms)与RVOT、RVA起搏时无显著差异。结论 :RV Bi起搏和BiV同步起搏的急性血液动力学效果无明显差异 ,但双部位起搏的效果明显优于单部位起搏 ;双部位起搏的QRSd也比单部位起搏明显缩短 相似文献
72.
目的 分析MELF (microcystic elongated and fragmented)浸润在子宫内膜癌诊断及预后判断中的临床价值。方法 回顾性分析2011年3月至2013年6月复旦大学附属妇产科医院收治的6例子宫内膜癌伴有MELF浸润病理类型患者的病例资料。分析MELF浸润与子宫内膜癌临床病理类型、分期及预后的相关性。结果 患者年龄43~67岁,中位年龄56.5岁,临床表现以阴道不规则出血或阴道异常排液为主。1例为子宫内膜样腺癌I级合并透明细胞癌ⅠB期;1例子宫内膜样腺癌Ⅰ级ⅠB期;3例子宫内膜样腺癌Ⅰ级ⅢC期;1例子宫内膜样腺癌Ⅰ级ⅣB期。其中4例存在淋巴结转移,5例存在脉管内转移。术后随访5~29个月,均未见复发及转移。结论 MELF浸润多见于较晚期子宫内膜样腺癌,多伴有淋巴结侵犯。存在MELF浸润的子宫内膜癌应尤其注意是否存在脉管累及及淋巴结转移。 相似文献
73.
Mehmet Rasih Sonsoz Aytac Oncul Erdem Cevik Huseyin Orta Mustafa Yilmaz Elif Ayduk Govdeli Asli Nalbant Zeynep Gizem Demirtakan Mirac Tonyali Damla Durmus Ilkay Anakli Ozlem Polat Yunus Catma Naci Senkal Alpay Medetalibeyoglu Murat Kose Samim Emet Tufan Tukek 《The American journal of the medical sciences》2021,361(5):591-597
BackgroundThe information on electrocardiographic features of patients with coronavirus disease 2019 (COVID-19) is limited. Our aim was to determine if baseline electrocardiographic features of hospitalized COVID-19 patients are associated with markers of myocardial injury and clinical outcomes.MethodsIn this retrospective, single center cohort study, we included 223 hospitalized patients with laboratory-confirmed COVID-19. Clinical, electrocardiographic and laboratory data were collected and analyzed. Primary composite endpoint of mortality, need for invasive mechanical ventilation, or admission to the intensive care unit was assessed.ResultsForty patients (17.9%) reached the primary composite endpoint. Patients with the primary composite endpoint were more likely to have wide QRS complex (>120 ms) and lateral ST-T segment abnormality. The multivariable Cox regression showed increasing odds of the primary composite endpoint associated with acute respiratory distress syndrome (odds ratio 7.76, 95% CI 2.67–22.59; p < 0.001), acute cardiac injury (odds ratio 3.14, 95% CI 1.26–7.99; p = 0.016), high flow oxygen therapy (odds ratio 2.43, 95% CI 1.05–5.62; p = 0.037) and QRS duration longer than >120 ms (odds ratio 3.62, 95% CI 1.39–9.380; p = 0.008) Patients with a wide QRS complex (>120 ms) had significantly higher median level of troponin T and pro-BNP than those without it. Patients with abnormality of lateral ST-T segment had significantly higher median level of troponin T and pro-BNP than patients without.ConclusionsThe presence of QRS duration longer than 120 ms and lateral ST-T segment abnormality were associated with worse clinical outcomes and higher levels of myocardial injury biomarkers. 相似文献
74.
Solution Behavior of Hydrolyzed Gradient Methyl/Phenyl Oxazoline Copolymers and Complexation with DNA 下载免费PDF全文
Partial hydrolysis of 2‐methyl‐2‐oxazoline/2‐phenyl‐2‐oxazoline gradient copolymers (MPOx copolymers) results in amphiphilic copolymers containing cationic ethylene imine, neutral hydrophilic 2‐methyl‐2‐oxazoline, and hydrophobic 2‐phenyl‐2‐oxazoline segments (HMPOx copolymers). The solution behavior of the HMPOx copolymers has been investigated in water, phosphate buffer saline (PBS), and fetal bovine serum (FBS) by static, dynamic, and electrophoretic light scattering and fluorescence spectroscopy. The copolymers form stable spherical aggregates in aqueous media with positive surface charge. The aggregates are found to interact extensively with proteins in FBS solutions. Soluble HMPOx/DNA complexes have also been formed in aqueous media at certain HMPOx/DNA compositions due to electrostatic interactions. The polyplexes have been studied in terms of structure and colloidal stability.
75.
John E. Madias 《Annals of noninvasive electrocardiology》2004,9(2):192-197
There is recent evidence that anasarca peripheral edema, irrespective of its etiology, attenuates ECG QRS potentials. Pulmonary edema (PE) also is thought to cause reduction in the amplitude of QRS complexes. The case reported herein is of a patient with severe PE, hypertension, left ventricular diastolic dysfunction, and no peripheral edema who did not show changes in the QRS complexes with the management of her pulmonary edema. Thus it appears that PE does not attenuate the amplitude of QRS complexes, and alleviation of this condition does not cause augmentation of QRS voltage. This is in contrast to alterations of peripheral edematous states in the setting of congestive heart failure, which result in changes in the QRS amplitude, as shown previously. 相似文献
76.
Bang LE Ripa RS Grande P Kastrup J Clemmensen PM Wagner GS 《Journal of electrocardiology》2008,41(6):609-613
Introduction
Magnetic resonance imaging using the delayed contrast-enhanced (DE-MRI) method can be used for characterizing and quantifying myocardial infarction (MI). Electrocardiogram (ECG) score after the acute phase of MI can be used to estimate the portion of left ventricular myocardium that has infracted. There are no comparison of serial changes on ECG and DE-MRI measuring infarct size.Aim
The general aim of this study was to describe the acute, healing, and chronic phases of the changes in infarct size estimated by the ECG and DE-MRI. The specific aim was to compare estimates of the Selvester QRS scoring system and DE-MRI to identify the difference between the extent of left ventricle occupied by infarction in the acute and chronic phases.Methods
In 31 patients (26 men, age 56 ± 9) with reperfused ST-elevation MI (11 anterior, 20 inferior), standard 12-lead ECG and DE-MRI were taken from 1 to 2 days (acute), 1 month (healing), and 6 months (chronic) after the MI. Selvester QRS scoring was used to estimate the infarct size from the ECG.Results
The correlation values between infarct size measured by DE-MRI and QRS scoring range from 0.33 to 0.43 higher for anterior than inferior infarcts. The infarct size estimated by QRS scoring was larger (about 5% of the left ventricle) than infarct size by DE-MRI acute and 1 month, but at 6 months, there was no difference. In about half of the patients, the QRS score agreed with DE-MRI in change of infarct size from acute to 6 months.Conclusion
In conclusion, the Selvester QRS scoring system is in half of the patients with reperfused first time MI in good accordance with DE-MRI in identifying a decrease or no change in the extent of left ventricle occupied by infarction in the acute and chronic phases. 相似文献77.
Fuyuki Aida Souske Yamaguchi Yohei Takatori Kentaro Nagamatsu Daichi Kiyokawa Kenichi Oyaizu Hiroyuki Nishide 《Macromolecular chemistry and physics.》2015,216(18):1850-1855
A newly established catalyst system for oxygen‐oxidative polymerization of diphenyl disulfide is reported. Combination of vanadyl compounds (e.g., VO(acac)2) and triphenylmethylium tetrakis(pentafluorophenyl)borate (TrB(C6F5)4) proceeds the polymerization to give poly(1,4‐phenylene sulfide) (PPS) at 100 °C. When triphenylmethylium tetrafluoroborate (TrBF4) is applied with vanadyl tetraphenylporphyrin (VO(TPP)) or N,N′‐(ethylenebis(salicylideneaminato))oxovanadium (VO(salen)), PPS is also given via polymerization under conditions near 160 °C. Combination of the vanadyl complex and the borate affords the first protic‐acid‐free catalytic system for the polymerization of the disulfide, suggesting the overall reaction to produce PPS and H2O from O2 and protons that are eliminated from the monomer.
78.
目的:利用国内医学研究常用ICR品系小鼠,在构建用于研究卵母细胞-卵丘细胞交互作用培养模型的基础上,研究卵母细胞及其产生的旁分泌因子生长分化因子9(GDF9)和骨形态发生蛋白15(BMP15)对排卵过程中的关键事件——卵丘扩展的调控作用?方法:通过显微手术制备摘除卵母细胞后的卵丘细胞复合体(OOX),并通过与卵母细胞共培养或GDF9和BMP15 处理研究卵母细胞及其特异释放的旁分泌因子对表皮生长因子(EGF)诱导卵丘扩展过程的调控?结果:成功构建了ICR小鼠OOX培养模型,发现卵母细胞及其释放的旁分泌因子GDF9和BMP15为EGF诱导卵丘扩展所必需?结论:ICR小鼠卵母细胞通过旁分泌机制促进排卵关键过程? 相似文献
79.
An interesting case of wide QRS tachycardia with right bundle branch block morphology: What is the mechanism? 下载免费PDF全文
80.
High‐density mapping for catheter ablation of premature ventricular complexes originating from left ventricular papillary muscles: A case series 下载免费PDF全文