AIM: To assess the safety and feasibility of peroral esophageal myotomy(POEM) in patients with achalasia.METHODS: From January 2012 to March 2014, 50 patients(28 men, 22 women; mean age: 42.8 years, range: 14-70 years...AIM: To assess the safety and feasibility of peroral esophageal myotomy(POEM) in patients with achalasia.METHODS: From January 2012 to March 2014, 50 patients(28 men, 22 women; mean age: 42.8 years, range: 14-70 years) underwent POEM. Pre- and postoperative symptoms were quantified using the Eckardt scoring system. Barium swallow and esophagogastroscopy were performed before and after POEM, respectively. Esophageal motility was evaluated in all patients, both preoperatively and one month after POEM treatment, using a high-resolution manometry system. Manometry data, Eckardt scores, lower esophageal sphincter pressure and barium swallow results were used to evaluate the effect of the procedure.RESULTS: POEM was successfully completed for all patients. The mean procedure time was 55.4 ± 17.3 min and the mean total length of myotomy of the circular esophagus was 10.5 ± 2.6 cm. No specific complications occurred, with the exception of two patients that developed as ymptomatic pneumomediastinum and subcutaneous emphysema. Clinical improvement in symptoms was achieved in all patients. Approximately 77.5% of patients experienced weight gain 6 mo after POEM, with an average of 4.78 kg(range: 2-15 kg). The lower esophageal sphincter resting pressure, four second integrated relaxation pressure and Eckardt scores were all significantly reduced after POEM(Ps < 0.05). A small segment of proximal esophageal peristalsis appeared postoperatively in two patients, but without normal esophageal peristalsis. The average diameter of the esophageal lumen decreased significantly from 4.39 to 3.09 cm(P < 0.01). CONCLUSION: POEM can relieve achalasia symptoms, improve gastroesophageal junction relaxation and restore esophageal body motility function, but not normal esophageal peristalsis.展开更多
As a combination of bio-mechanism and engineering technology, robot fish has become a multidisci- plinary research that mainly involves both hydrodynamics-based control and actuation technology. This paper presents a ...As a combination of bio-mechanism and engineering technology, robot fish has become a multidisci- plinary research that mainly involves both hydrodynamics-based control and actuation technology. This paper presents a simplified propulsive model for carangiform propulsion, which is a swimming mode suitable for high speed and high efficiency. The carangiform motion is modeled as an N-joint nscillating mechanism that is composed of two basic components： the streamlined fish body represented by a planar spline curve and its hmate caudal tail by an oscillating foil. The speed of fish＇s straight swimming is adjusted by modulating the joint＇s oscillating frequency, and its orientation is tuned by different joint＇s deflection. The results from actual experiment showed that the proposed simplified propulsive model could be a viable eandidate for application in aquatic： swimming vehicles.展开更多
文摘AIM: To assess the safety and feasibility of peroral esophageal myotomy(POEM) in patients with achalasia.METHODS: From January 2012 to March 2014, 50 patients(28 men, 22 women; mean age: 42.8 years, range: 14-70 years) underwent POEM. Pre- and postoperative symptoms were quantified using the Eckardt scoring system. Barium swallow and esophagogastroscopy were performed before and after POEM, respectively. Esophageal motility was evaluated in all patients, both preoperatively and one month after POEM treatment, using a high-resolution manometry system. Manometry data, Eckardt scores, lower esophageal sphincter pressure and barium swallow results were used to evaluate the effect of the procedure.RESULTS: POEM was successfully completed for all patients. The mean procedure time was 55.4 ± 17.3 min and the mean total length of myotomy of the circular esophagus was 10.5 ± 2.6 cm. No specific complications occurred, with the exception of two patients that developed as ymptomatic pneumomediastinum and subcutaneous emphysema. Clinical improvement in symptoms was achieved in all patients. Approximately 77.5% of patients experienced weight gain 6 mo after POEM, with an average of 4.78 kg(range: 2-15 kg). The lower esophageal sphincter resting pressure, four second integrated relaxation pressure and Eckardt scores were all significantly reduced after POEM(Ps < 0.05). A small segment of proximal esophageal peristalsis appeared postoperatively in two patients, but without normal esophageal peristalsis. The average diameter of the esophageal lumen decreased significantly from 4.39 to 3.09 cm(P < 0.01). CONCLUSION: POEM can relieve achalasia symptoms, improve gastroesophageal junction relaxation and restore esophageal body motility function, but not normal esophageal peristalsis.
文摘As a combination of bio-mechanism and engineering technology, robot fish has become a multidisci- plinary research that mainly involves both hydrodynamics-based control and actuation technology. This paper presents a simplified propulsive model for carangiform propulsion, which is a swimming mode suitable for high speed and high efficiency. The carangiform motion is modeled as an N-joint nscillating mechanism that is composed of two basic components： the streamlined fish body represented by a planar spline curve and its hmate caudal tail by an oscillating foil. The speed of fish＇s straight swimming is adjusted by modulating the joint＇s oscillating frequency, and its orientation is tuned by different joint＇s deflection. The results from actual experiment showed that the proposed simplified propulsive model could be a viable eandidate for application in aquatic： swimming vehicles.
