RESUMEN
Attractive Bose-Einstein condensates of dilute alkali gases are unstable against collapse in two- and three-dimensional free space. Nevertheless, we demonstrate that the spin-orbit coupling of the two-component condensates counteracts the tendency of collapse and makes the system preferable to an extended spatial distribution in the three-dimensional case. Furthermore, stable topological objects can be formed in the condensates, which are shown to be the lowest energy states. Two configurations of the density profiles, called three-dimensional skyrmion and three-dimensional dimeron, respectively, are identified depending on the strength of the spin-orbit coupling.
RESUMEN
OBJECTIVE: To explore the postoperative complication and its preventive measure of cervical open-door expansive laminoplasty with lateral mass screw fixation in treating cervical canal stenosis. METHODS: From February 2008 to July 2011, 33 patients with cervical canal stenosis underwent cervical open-door expansive laminoplasty with lateral mass screw fixation. JOA score was used to evaluate clinical effects before and after operation. Of them, complications occurred in 6 cases, male in 2 cases and female in 4 cases. The reason of complications were analyzed. RESULTS: All the patients were followed up from 6 months to 2 years with an average of 10.3 months. The improvement rate of JOA was 78.8% and incidence rate of complication was 18.2% (6 cases). There were 2 cases of axiality symptoms, 1 case of lateral mass screw pulled-out, 2 cases of cerebrospinal fluid leakage with wound dehiscence, 1 case of nerve root parlysis. These complications correlated with operative design, manipulation,improved degree of cervical curvature,postoperative management and cooperation of patient. CONCLUSION: As an effective treatment, cervical open-door expansive laminoplasty with lateral mass screw fixation has lower incidence of axiality pain. Preoperative examination ,postoperative management ,meticulous surgical skill are very important to avoid complications.