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排序方式: 共有1681条查询结果,搜索用时 15 毫秒
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Structure function interface with sequential shortening of basal and apical components of the myocardial band 总被引:1,自引:0,他引:1
Manuel Castella Gerald D. Buckberg Saleh Saleh Morteza Gharib 《European journal of cardio-thoracic surgery》2005,27(6):980-987
Objective: To mechanically test the intact cardiac structure to determine the sequence of contraction within the myocardial mass to try to explain ejection and suction. Methods: In 24 pigs (30–85 kg), segment shortening at the site of sonomicrometer crystals was continuously recorded. The ECG evaluated rhythm, and Millar pressure transducers measured intraventricular pressure and dP/dt. Results: Study of segment shortening defined a sequence of contraction within the myocardial mass, starting at the free wall of the right ventricle and on the endocardial side of the antero-septal wall of the left. Crystal location defined underlying contractile trajectory; transverse in right ventricle followed by basal posterior left ventricle, and from the endocardial anterior wall to the posterior apical segment and finally to the epicardial side of the anterior wall. Mean shortening fraction averaged 18±3%, with endocardial exceeding epicardial shortening by 5±1%. Epicardial segment crystal displacement followed endocardial shortening by 82±23 ms in the anterior wall, and finished 92±33 ms after endocardial shortening stopped, time frame that matches the interval of fast drop of ventricular pressure and the start of suction. Conclusions: Crystal shortening fraction sequence followed the rope-like myocardial band model to contradict traditional thinking, with two starting points of excitation–contraction, the right anterior free wall of the right ventricle, and the endocardial side of the anterior wall. Active suction may be due to active shortening of the epicardial fibers of the anterior wall, because relaxation was not detected when both mitral and aortic valves were closed during the interval previously termed ‘isovolumetric relaxation’. 相似文献
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Hamed Nikoupour MD Peyman Arasteh MD MPH Alireza Shamsaeefar MD Fardin Ghanbari MD Arash Boorboor MD Ali Mosa Jafar Almayali MD Mojtaba Shafiekhani PharmD Ph.D Pirouz Samidoust MD Reza Shahriarirad MD Alireza Shojazadeh MD Keivan Ranjbar MD Mohammad Hasan Darabi MD Sina Tangestanipour MD Seyed Morteza Hosseini MD Leila Zahiri MD Saman Nikeghbalian MD 《JPEN. Journal of parenteral and enteral nutrition》2022,46(4):946-957
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Greenfield LJ Proctor MC Michaels AJ Taheri PA 《Journal of vascular surgery》2000,32(3):490-5; discussion 496-7
OBJECTIVE: The purpose of this study was to describe outcomes for patients with trauma who had vena caval filters placed in the absence of venous thromboembolic disease (group P) and compare them with outcomes for patients with trauma who had filters placed after either deep venous thrombosis or pulmonary embolism (group T). DESIGN: The study is a case series of consecutive patients who received vena caval filters after traumatic injury. Data were collected prospectively at the time of filter placement from reports of diagnostic studies obtained for clinical indications and during the annual follow-up examinations. Event rate findings are based on objective tests. Data were obtained from the Michigan Vena Cava Filter Registry. RESULTS: Filters were placed in 385 patients with trauma; 249 of these filters were prophylactic (group P). Event rates were similar in the two groups. New pulmonary embolism was diagnosed in 1.5% of the patients in group P and 2% of the patients in group T. Caval occlusion rates were 3.5% for group P and 2.3% for group T. In all, 15.6% of the patients in group P had deep venous thrombosis or pulmonary embolism after placement. The frequencies of lower extremity swelling and use of support hose were higher in group T than in group P (43% vs 25% and 25% vs 3.5%, respectively; P <.005). Outcomes were comparable in the two groups with respect to mechanical stability of the filter. CONCLUSIONS: The prophylactic indication for vena caval filter placement in patients with trauma is associated with a low incidence of adverse outcomes while providing protection from fatal pulmonary embolism. The current challenge is to limit the number of unnecessary placements through improved methods of risk stratification. 相似文献
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目的:研究开角型青光眼患者非穿透性深层巩膜切除术后高阶像差的变化。
方法:研究包括20例患者20眼, 其中10例为原发性开角型青光眼, 10例为继发性开角型青光眼。患者术前接受非穿透性深层巩膜切除术,并辅以Tenon囊下注射(0.02% of MMC)。术前及术后1、3mo用i-Trace分析仪测定角膜总高阶像差。每次随访时评估眼压(IOP)、最佳矫正视力(BCVA)和眼泡形态。手术的成功率分为完全成功、相对成功和失败。
结果:术前IOP为24.05±3.07 mmHg,平均用药2.85±0.67次,随访3mo后,IOP为12.30±3.32 mmHg,平均用药0.70±0.98次。随访期间IOP均明显下降(P<0.001)。术后随访1mo,总高阶像差(HOT)均方根(RMS)和总球型像差值明显升高,3mo后下降。术后各时间段三叶肌和全眼昏迷样像差变化无统计学意义。术后1mo HOT RMS及球形角膜均明显增加,3mo随访后明显减少。术后角膜三叶肌变化与术前相比无统计学意义。患者年龄和IOP对HOT和角膜HOT的变化无显著影响。
结论:深度巩膜切除术后1mo内角膜和眼部高阶像差增加,3mo后下降,与术前相比无统计学意义。在3mo随访时,患者的BCVA和等效球镜(SE)与术前相比无统计学差异。 相似文献
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Sarang Younesi Bahareh Yazdani Mohammad Mahdi Taheri Amin Pourandokht Saadati Soudabeh Jamali MohammadHossein Modarresi Shahram Savad Saloomeh Amidi Homayoun Razavi Soudeh GhafouriFard 《Journal of clinical laboratory analysis》2022,36(7)
BackgroundNowadays, neonatal screening has become an essential part of routine newborn care in the world. This is a non‐invasive evaluation that evaluated inborn errors of metabolisms (IEMs) using tandem mass spectrometry (LC‐MS/MS) for the evaluation of the baby''s risk of certain metabolic disorders.MethodsThis retrospective study was conducted on 39987 Iranian newborns who were referred to Nilou Medical Laboratory, Tehran, Iran, for newborn screening programs of IEMs. We incorporated second‐tier tests and secondary biomarkers to improve positive predictive value (PPV).ResultsStatistical data were recorded via call interviewing in 6–8 months after their screening tests. The overall prevalence of IEM was 1:975. The mean age of all participants was 3.9 ± 1.1 days; 5.1% of participants were over 13 days and 7.7% were preterm or underweight. A total of 11384 (29.4%) of the cases were born in a consanguineous family. The type of delivery was the cesarean section in 8332 (51.3%) valid cases. The neonatal screening results had an overall negative predictive value (NPV) of 100% and the overall PPV of 40.2%. The false‐positive rate was 0.15%.ConclusionThis study showed a high incidence of metabolic disease due to a high rate of consanguineous marriages in Iran and indicated that incorporation of second‐tier tests and secondary biomarkers improves PPV of neonatal screening programs. 相似文献
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