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101.
The design and performance of annular antenna arrays with reflectors is presented. Arrays with three shapes of reflectors are analysed and simulated. These include the corner reflector, the circular reflector and the elliptical reflector. Power-density distributions within the annular arrays with and without reflectors are obtained by using the FDTD method. Also, the image theory method is used to verify the FDTD results in one case. By comparing the power-density distribution pattern of all four of the array designs (three with different reflectors, one without reflector), it is readily seen in each case that the array with reflectors yields better power-efficiency than the array without reflectors and the elliptical reflector yields the best performance. Comparisons of each array are made using 4, 6 and 8 antennae in the annular array. By using the optimized results of the elliptical reflector, the requirement for the input-power level to each antenna is greatly reduced.  相似文献   
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104.
We describe a 77‐year‐old female with hypertrophic cardiomyopathy in whom live/real time three‐dimensional transesophageal echocardiography (3DTEE) provided incremental value over two‐dimensional transthoracic and transesophageal echocardiography (2DTTE, 2DTEE) and three‐dimensional transthoracic echocardiography (3DTTE) in making a more comprehensive assessment and a more confident diagnosis of caseous mitral annular calcification. 3DTEE revealed a portion of the mass to consist of small, multiple, highly echogenic discrete band‐like and punctate areas within a relatively much less echogenic stroma and surrounded by a well defined highly echogenic border. This appearance correlated with the pathological findings of calcific granules/strands located in a liquefied or semiliquefied interior providing a typical toothpaste like appearance. The highly echogenic outer border represented the residual outer portion or rim of the calcific mass which did not undergo liquefaction. These findings on 3DTEE which correlated with the toothpaste like appearance seen at surgery were not visualized on 2DTTE, 2DTEE, and 3DTTE. (Echocardiography 2010;27:1147‐1150)  相似文献   
105.
目的 对列当Orobanche caerulescens进行生药学研究.方法 采用性状及显微鉴别的方法,对列当的性状,茎的组织构造和粉末的显微特征进行鉴别.结果 列当茎的横切面由表皮、皮层、维管束和髓组成.外韧型维管束呈深波状环列;木质部细胞全部木化;具较发达的木纤维和明显的髓射线.粉末中可见花粉粒、非腺毛、网纹细胞、淀粉粒、纤维及导管.结论 列当的以上特征可为鉴别其真伪及制定其质量标准提供可靠的依据.  相似文献   
106.

Background

Isolated tricuspid valve replacement is rare when performed as a re-operation after a left side operation. It is important to know the factors that determine mortality and morbidity. Tricuspid Annular Plane Systolic Excursion (TAPSE) is a scoring system that is used with non-invasive Doppler echocardiography to determine right ventricular (RV) function. This study analyzed TAPSE scores and adverse outcomes of isolated tricuspid valve surgery in patients with previous cardiac surgery.

Methods

All patients who underwent tricuspid valve replacement between January 2014 and December 2015 were retrospectively reviewed. Patients having concomitant mitral or aortic valve surgery were excluded. These patients were divided into two groups: TAPSE >14 mm and TAPSE ≤14 mm. In-hospital outcomes were compared.

Results

A total of 26 patients with severe tricuspid valve regurgitation underwent tricuspid valve replacement. There were 5 males (19.2%) and 21 females (80.8%). The average age at operation was 54.77±9.61 years (range, 27–69 years). There were 16 patients in the TAPSE >14 mm group and 10 patients in the TAPSE ≤14 mm group. The BNP in the TAPSE >14 mm group was significant (TAPSE >14 mm 672.34±229.98 versus TAPSE ≤14 mm 1,054.79±684.69, P=0.03). The median cardiopulmonary bypass (CPB) time and red blood cell (RBC) transfusions in the two groups were not different. The need for prolonged ventilatory support (>48 h) in the two groups was also not different (TAPSE> 14 mm 91.2±12.31 vs. TAPSE ≤14 mm 39.00±36.80, P=0.46). Moreover, hospital stays were similar between the two groups. No differences were found in postoperative renal and respiratory complications.

Conclusions

It is important to determine the right ventricule function quantitatively. The TAPSE score is an important parameter that determines the cardiac index and right ventricle function. It should be used for the prediction of mortality and morbidity with all the other parameters as a whole.  相似文献   
107.
ObjectivesThe aim of this study was to assess 1-year clinical outcomes among high-risk patients with failed surgical mitral bioprostheses who underwent transseptal mitral valve-in-valve (MViV) with the SAPIEN 3 aortic transcatheter heart valve (THV) in the MITRAL (Mitral Implantation of Transcatheter Valves) trial.BackgroundThe MITRAL trial is the first prospective study evaluating transseptal MViV with the SAPIEN 3 aortic THV in high-risk patients with failed surgical mitral bioprostheses.MethodsHigh-risk patients with symptomatic moderate to severe or severe mitral regurgitation (MR) or severe mitral stenosis due to failed surgical mitral bioprostheses were prospectively enrolled. The primary safety endpoint was technical success. The primary THV performance endpoint was absence of MR grade ≥2+ or mean mitral valve gradient ≥10 mm Hg (30 days and 1 year). Secondary endpoints included procedural success and all-cause mortality (30 days and 1 year).ResultsThirty patients were enrolled between July 2016 and October 2017 (median age 77.5 years [interquartile range (IQR): 70.3 to 82.8 years], 63.3% women, median Society of Thoracic Surgeons score 9.4% [IQR: 5.8% to 12.0%], 80% in New York Heart Association functional class III or IV). The technical success rate was 100%. The primary performance endpoint in survivors was achieved in 96.6% (28 of 29) at 30 days and 82.8% (24 of 29) at 1 year. Thirty-day all-cause mortality was 3.3% and was unchanged at 1 year. The only death was due to airway obstruction after swallowing several pills simultaneously 29 days post-MViV. At 1-year follow-up, 89.3% of patients were in New York Heart Association functional class I or II, the median mean mitral valve gradient was 6.6 mm Hg (interquartile range: 5.5 to 8.9 mm Hg), and all patients had MR grade ≤1+.ConclusionsTransseptal MViV in high-risk patients was associated with 100% technical success, low procedural complication rates, and very low mortality at 1 year. The vast majority of patients experienced significant symptom alleviation, and THV performance remained stable at 1 year.  相似文献   
108.
Anatomic continuity between the anterior mitral leaflet and the aortic root may predispose those patients with aortic root pathology to functional changes of the mitral valve without any involvement of this valve. A 34-year-old man presented with aortic valve endocarditis. Transthoracic echocardiograpy showed severe aortic regurgitation with a large aortic root abscess. The anterior leaflet of the mitral valve was displaced towards the apex of the heart causing moderate mitral regurgitation. The patient underwent aortic valve replacement with reconstruction of the aortic annulus and ventriculoaortic continuity. This procedure alone restored the mitral valve structure and function without any need for intervention on the mitral valve. Aortic abscess is a serious complication of aortic valve endocarditis and may alter the function of other structures of the heart, especially the mitral valve. Restoration of aortic wall integrity and left ventricular – aortic continuity usually restores the mitral valve structure and function if the valve is unaffected by the infection. A decision on the mitral valve should be made following correction of the aortic pathology.  相似文献   
109.
目的:探讨后路椎间盘镜腰椎间盘切除术(MED)与显微镜下腰椎间盘切除术(MSLD)治疗腰椎间盘突出症(LDH)的中期临床疗效。方法将2009年3月至2010年4月于兰州大学第二医院骨科接受手术治疗的98例单节段LDH患者随机分为两组,其中接受MED治疗的患者44例(MED组),接受MSLD治疗的患者54例(MSLD组)。采用视觉疼痛模拟评分(VAS)、JOA评分和Oswestry功能障碍指数(ODI)评价两组患者手术疗效。结果MED组创伤小、出血少,术后恢复快。两组患者手术切口长度、出血量、恢复工作时间比较,均差异有统计学意义(P<0.01);手术时间、住院时间、并发症发生率比较,差异无统计学意义(P>0.05)。MED组和MSLD组患者术后平均随访时间为49.13个月和47.24个月,末次随访时两组患者术后腰腿痛VAS评分、JOA评分、ODI指数较术前均明显改善(P<0.01),组间比较差异无统计学意义(P>0.05)。结论MED与MSLD均是治疗单节段LDH的有效方法,但MED创伤小、术后患者可早期下地活动,是理想的微创手术。  相似文献   
110.
Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are increased in plasma lipids and blood cell membranes in response to supplementation. Whilst arachidonic acid (AA) is correspondingly decreased, the effect on other fatty acids (FA) is less well described and there may be site-specific differences. In response to 12 months EPA + DHA supplementation in doses equivalent to 0–4 portions of oily fish/week (1 portion: 3.27 g EPA+DHA) multinomial regression analysis was used to identify important FA changes for plasma phosphatidylcholine (PC), cholesteryl ester (CE) and triglyceride (TAG) and for blood mononuclear cells (MNC), red blood cells (RBC) and platelets (PLAT). Dose-dependent increases in EPA + DHA were matched by decreases in several n-6 polyunsaturated fatty acids (PUFA) in PC, CE, RBC and PLAT, but were predominantly compensated for by oleic acid in TAG. Changes were observed for all FA classes in MNC. Consequently the n-6:n-3 PUFA ratio was reduced in a dose-dependent manner in all pools after 12 months (37%–64% of placebo in the four portions group). We conclude that the profile of the FA decreased in exchange for the increase in EPA + DHA following supplementation differs by FA pool with implications for understanding the impact of n-3 PUFA on blood lipid and blood cell biology.  相似文献   
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