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Objectives: To report our initial experience with transumbilical laparo‐endoscopic single‐site adrenalectomy for adrenal tumors by using a single port with a multichannel cannula and bent laparoscopic instrumentation. Methods: Between December 2009 and December 2010, 30 patients underwent transumbilical laparo‐endoscopic single‐site adrenalectomy at our hospital. The procedure was carried out for adrenal cortical adenoma in 17 patients, adrenal pheochromocytoma in seven patients and other types of tumors in six patients. A multichannel port, bent laparoscopic instruments and Opti4 laparoscopic electrodes were used in all patients. The intraperitoneal space was approached through the umbilicus. The multichannel port was placed through a 2‐cm incision at the inner edge of the umbilicus. A 5‐mm flexible laparoscope was introduced to maintain an adequate laparoscopic view, and surgical specimens were extracted using an Endocatch bag. Results: All procedures were successfully completed, with only one incision through the umbilicus, and without conversion to a standard laparoscopic approach. Mean operative time was 120.1 ± 34.7 min. Tumor laterality and patient body mass index did not affect surgical morbidity. The initial 15 patients had a significantly longer mean pneumoperitoneum time (95.8 ± 37.5 min) than the last 15 patients (70.5 ± 18.7 min). Only one postoperative complication was observed (postoperative hematoma). Conclusions: A transumbilical approach for laparo‐endoscopic single‐site adrenalectomy is safe and feasible, and it results in superior cosmesis. Improvements in surgical devices might facilitate further development of this approach.  相似文献   
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Blood compatibility of a ventricular assist device (VAD) depends on the dynamics of blood flow. The focus in most previous studies was on blood flow in the VAD. However, the tip shape and position of the VAD inflow cannula influence the dynamics of intraventricular blood flow and thus thrombus formation in the ventricle. In this study, blood flow in the left ventricle (LV) under support with a catheter-type continuous flow blood pump was investigated. The flow field was analyzed both numerically and experimentally to investigate the effects of catheter tip shape and its insertion depth on intraventricular flow patterns. A computational model of the LV cavity with a simplified shape was constructed using computer-aided design software. Models of catheters with three different tip shapes were constructed and each was integrated to the LV model. In addition, three variations of insertion depth were prepared for all models. The fully supported intraventricular flow field was calculated by computational fluid dynamics (CFD). A transparent LV model made of silicone was also fabricated to analyze the intraventricular flow field by the particle image velocimetry technique. A mock circulation loop was constructed and water containing tracer particles was circulated in the loop. The motion of particles in the LV model was recorded with a digital high-speed video camera and analyzed to reveal the flow field. The results of numerical and experimental analyses indicated the formation of two large vortices in the bisector plane of the mitral and aortic valve planes. The shape and positioning of the catheter tip affected the flow distribution in the LV, and some of these combinations elongated the upper vortex toward the ventricular apex. Assessment based on average wall shear stress on the LV wall indicated that the flow distribution improved the washout effect. The flow patterns obtained from flow visualization coincided with those calculated by CFD analysis. Through these comparisons, the numerical analysis was validated. In conclusion, results of these numerical and experimental analyses of flow field in the LV cavity provide useful information when designing catheter-type VADs.  相似文献   
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Background

Laparoscopic inguinal hernia repair is associated with a decrease in postoperative pain, shortened hospital stay, earlier return to normal activity, and decrease in chronic pain. Moreover, laparoscopic surgery performed with needlescopic instruments has more advantages than conventional laparoscopic surgery. However, there are few reports of large-scale laparoscopic transabdominal preperitoneal inguinal hernia repair using needlescopic instruments (nTAPP). This report reviews our experiences with 352 nTAPP in 317 patients during the 15-year period from April 1996 to April 2011.

Methods

We performed nTAPP as the method of choice in 88.5% of all patients presenting with inguinal hernia. To perform the nTAPP, 3-mm instruments were used. A 5-mm laparoscope was inserted from the umbilicus, and surgical instruments were inserted through 5- and 3-mm trocars. After reduction of the hernia sac and dissection of the preperitoneal space, we placed polyester mesh or polypropylene soft mesh with staple fixation. The peritoneum was closed with 3–0 silk interrupted sutures.

Results

The mean operative time was 102.9?min for unilateral hernias and 155.8?min for bilateral hernias. There was no conversion to open repair. Forty-three patients (13.6%) used postoperative analgesics, and the mean frequency of use was 0.5 times. Regarding intraoperative complications, we observed one bladder injury, but no bowel injuries or major vessel injuries. Postoperative complications occurred in 32 patients (10.1%). One patient with a retained lipoma required reoperation. There was no incidence of chronic pain or mesh infection. The operative time for experienced surgeons (≥20 repairs) was significantly shorter than that of inexperienced surgeons (<20 repairs; P?Conclusions The nTAPP was a safe and useful technique for inguinal hernia repair. Large prospective, randomized controlled trials will be required to establish the benefit of nTAPP.  相似文献   
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[Purpose] The purpose of this study was to compare the intramuscular balance ratios of the upper trapezius muscle (UT) and the lower trapezius muscle (LT), and the intermuscular balance ratios of the UT and the serratus anterior muscle (SA) among prone extension (ProExt), prone horizontal abduction with external rotation (ProHAbd), forward flexion in the side-lying position (SideFlex), side-lying external rotation (SideEr), shoulder flexion with glenohumeral horizontal abduction load (FlexBand), and shoulder flexion with glenohumeral horizontal adduction load (FlexBall) in the standing posture. [Methods] The electromyographic (EMG) activities of the UT, LT and SA were measured during the tasks. The percentage of maximum voluntary isometric contraction (%MVIC) was calculated for each muscle, and the UT/LT ratios and the UT/SA ratios were compared among the tasks. [Results] The UT/LT ratio with the FlexBand was not significantly different from those of the four exercises in the side-lying and prone postures. The UT/SA ratio with the FlexBall demonstrated appropriate balanced activity. [Conclusion] In an anti-gravity posture, we recommend the FlexBand and the FlexBall for inducing balanced UT/LT and UT/SA ratios, respectively.Key words: Scapular muscle exercise, Balanced scapular muscle activity, Electromyography  相似文献   
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BackgroundFew studies have examined the efficacy or safety of a transdermal β2 agonist as add-on medicationto long-term leukotriene receptor antagonist (LTRA) therapy in pediatric asthma patients.MethodsIn this randomized, open-label, multicenter clinical trial, children aged 4-12 years on long-term LTRA therapy were treated with tulobuterol patches (1-2 mg daily) or oral sustained-release theophylline (usual dose, 4-5 mg_kg daily) for 4 weeks. LTRAs were continued throughout the trial. Outcomes included volume peak expiratory flow (% PEF), fractional exhaled nitric oxide (FeNO), clinical symptoms and adverse events.ResultsThirty-three and 31 patients were treated with tulobuterol patches and theophylline, respectively. % PEF measured in the morning and before bedtime was significantly higher at all times in the treatment period compared with baseline in the tulobuterol patch group (p < 0.001), and was significantly higher in the tulobuterol patch group compared with the theophylline group. FeNO was similar and unchanged from baseline in both groups. There were no drug-related adverse events in either group.ConclusionsThese results suggest that short-term use of a transdermal β2 agonist is an effective therapy for pediatric asthma without inducing airway inflammation in children on long-term LTRA therapy.  相似文献   
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