1 概述
分散控制系统（Distrubuted Control System，DCS）是融计算机技术、控制技术、通信技术、CRT技术为一体，对生产过程进行监视、控制、操作和管理的一种新型控制系统。随着火电机组单机容量的增大、参数的提高，热力系统变得更...1 概述
分散控制系统（Distrubuted Control System，DCS）是融计算机技术、控制技术、通信技术、CRT技术为一体，对生产过程进行监视、控制、操作和管理的一种新型控制系统。随着火电机组单机容量的增大、参数的提高，热力系统变得更加复杂，在运行中须监视的信息量和用于控制的指令量迅速增加。分散控制系统由于其高度的可靠性、强大的功能、灵活的配置，特别是其完善的通讯系统，能及时、准确地在DCS各子系统中传递大量数据，使其各子系统能够有机结合，共同完成复杂的控制任务，从而在火电厂热控系统中获得了广泛的应用。展开更多
Objective： The aim of our study was to evaluate the clinical results and acute side effects of late course three-dimensional conformal radiotherapy （3DCRT） for esophageal carcinoma. Methods： From January 2004 to O...Objective： The aim of our study was to evaluate the clinical results and acute side effects of late course three-dimensional conformal radiotherapy （3DCRT） for esophageal carcinoma. Methods： From January 2004 to October 2006, 70 patients with esophageal carcinoma received late course 3DCRT. Their clinical data were analyzed retrospectively. The short-term clinical results, acute side effects, local control rates and survival rates were evaluated. Results： The complete response rate was 62.9%, partial response rate was 35.7%, and the overall response rate was 98.6%. The 1-, 2-and 3-year local control rates were 77.1%, 51.4% and 45.7%, respectively. The 1-, 2-and 3-year overall survival rates were 75.7%, 54.3% and 38.6%, respectively. The median survival time was 26 months. Conclusion： The technique of late course 3DCRT is an effective treatment for esophageal carcinoma and tend to improve the overall survival rate.展开更多
Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB...Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular （LV） region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance （NICD） pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.展开更多
Objective: The study is a comparative study, the aim of which is to compare 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) in treating nasopharyngeal carcinomas; dosimetricall...Objective: The study is a comparative study, the aim of which is to compare 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) in treating nasopharyngeal carcinomas; dosimetrically evaluating and comparing both techniques as regard target coverage and doses to organs at risk (OAR). Methods: Twenty patients with nasopharyngeal carcinoma were treated by 3D-CRT technique and another 20 patients were treated by IMRT. A dosimetric comparison was done by performing two plans for the same patient using Eclipse planning system (version 8.6). Results: IMRT had a better tumor coverage and conformity index compared to 3D-CRT plans (P value of 0.001 and 0.004), respectively. As for the dose homogeneity it was also better in the IMRT plans and the reason for this was attributed to the dose inhomogeneity at the photon/electron junction in the 3D-CRT plans (P value 0.032). Also, doses received by the risk structures, particularly parotids, was significantly less in the IMRT plans than those of 3D-CRT (P value 0.001). Conclusion: IMRT technique was clearly able to increase the dose delivery to the target volume, improve conformity and homogeneity index and spare the parotid glands in comparison to 3D-CRT technique.展开更多
Objective： The work is a comparative study between two modalities of radiation therapy, the aim of which is to compare 3D conformal radiation therapy （3D-CRT） and intensity modulated radiation therapy （IMRT） in t...Objective： The work is a comparative study between two modalities of radiation therapy, the aim of which is to compare 3D conformal radiation therapy （3D-CRT） and intensity modulated radiation therapy （IMRT） in treating posterior fossa boost in children with high risk medulloblastorna; dosimetrically evaluating and comparing both techniques as regard target coverage and doses to organs at risk （OAR）. Methods： Twenty patients with high risk medulloblastoma were treated by 3D-CRT technique. A dosimetric comparison was done by performing two plans for the posterior fossa boost, 3D-CRT and IMRT plans, for the same patient using Eclipse planning system （version 8.6）. Results： IMRT had a better conformity index compared to 3D-CRT plans （P value of 0.000）. As for the dose homogeneity it was also better in the IMRT plans, yet it hasn＇t reached the statistical significant value. Also, doses received by the cochleae, brainstem and spinal cord were significantly less in the IMRT plans than those of 3D-CRT （P value 〈 0.05）. Conclusion： IMRT technique was clearly able to improve conformity and homogeneity index, spare the cochleae, reduce dose to the brainstem and spinal cord in comparison to 3D- CRT technique.展开更多
文摘1 概述
分散控制系统（Distrubuted Control System，DCS）是融计算机技术、控制技术、通信技术、CRT技术为一体，对生产过程进行监视、控制、操作和管理的一种新型控制系统。随着火电机组单机容量的增大、参数的提高，热力系统变得更加复杂，在运行中须监视的信息量和用于控制的指令量迅速增加。分散控制系统由于其高度的可靠性、强大的功能、灵活的配置，特别是其完善的通讯系统，能及时、准确地在DCS各子系统中传递大量数据，使其各子系统能够有机结合，共同完成复杂的控制任务，从而在火电厂热控系统中获得了广泛的应用。
文摘Objective： The aim of our study was to evaluate the clinical results and acute side effects of late course three-dimensional conformal radiotherapy （3DCRT） for esophageal carcinoma. Methods： From January 2004 to October 2006, 70 patients with esophageal carcinoma received late course 3DCRT. Their clinical data were analyzed retrospectively. The short-term clinical results, acute side effects, local control rates and survival rates were evaluated. Results： The complete response rate was 62.9%, partial response rate was 35.7%, and the overall response rate was 98.6%. The 1-, 2-and 3-year local control rates were 77.1%, 51.4% and 45.7%, respectively. The 1-, 2-and 3-year overall survival rates were 75.7%, 54.3% and 38.6%, respectively. The median survival time was 26 months. Conclusion： The technique of late course 3DCRT is an effective treatment for esophageal carcinoma and tend to improve the overall survival rate.
文摘Cardiac resynchronization therapy （CRT） is associated with a favorable outcome only in patients with left bundle branch block （LBBB） pattern and in patients with a QRS duration 〉 150 ms, in patients with non-LBBB pattern with a QRS duration of 120-150 ms usually is not beneficial. After adjusting for QRS duration, QRS morphology was no longer a determinant of the clinical response to CRT. In contrast to the mainstream view, we hypothesized that the unfavorable CRT outcome in patients with non-LBBB and a QRS duration of 120-150 ms is not due to the QRS morphology itself, but to less dyssynchrony and unfavorable patient characteristics in this subgroup, such as more ischemic etiology and greater prevalence of male patients compared with patients with LBBB pattern. Further, the current CRT technique is devised to eliminate the dyssynchrony present in patients with LBBB pattern and inappropriate to eliminate the dyssynchrony in patients with non-LBBB pattern. We also hypothesized that electrocardiography may also provide information about the presence of interventricular and left intraventricular dyssynchrony and the approximate location of the latest activated left ventricular （LV） region. To this end, we devised new ECG criteria to estimate interventricular and LV intraventricular dyssynchrony and the approximate location of the latest activated LV region. Our preliminary data demonstrated that the latest activated LV region in patients with nonspecific intraventricular conduction disturbance （NICD） pattern might be at a remote site from that present in patients with LBBB pattern, which might necessitate the invention of a novel CRT technique for patients with NICD pattern. The application of the new interventricular and LV intraventricular dyssynchrony ECG criteria and a potential novel CRT technique might decrease the currently high nonresponder rate in patients with NICD pattern.
文摘Objective: The study is a comparative study, the aim of which is to compare 3D conformal radiation therapy (3D-CRT) and intensity modulated radiation therapy (IMRT) in treating nasopharyngeal carcinomas; dosimetrically evaluating and comparing both techniques as regard target coverage and doses to organs at risk (OAR). Methods: Twenty patients with nasopharyngeal carcinoma were treated by 3D-CRT technique and another 20 patients were treated by IMRT. A dosimetric comparison was done by performing two plans for the same patient using Eclipse planning system (version 8.6). Results: IMRT had a better tumor coverage and conformity index compared to 3D-CRT plans (P value of 0.001 and 0.004), respectively. As for the dose homogeneity it was also better in the IMRT plans and the reason for this was attributed to the dose inhomogeneity at the photon/electron junction in the 3D-CRT plans (P value 0.032). Also, doses received by the risk structures, particularly parotids, was significantly less in the IMRT plans than those of 3D-CRT (P value 0.001). Conclusion: IMRT technique was clearly able to increase the dose delivery to the target volume, improve conformity and homogeneity index and spare the parotid glands in comparison to 3D-CRT technique.
文摘Objective： The work is a comparative study between two modalities of radiation therapy, the aim of which is to compare 3D conformal radiation therapy （3D-CRT） and intensity modulated radiation therapy （IMRT） in treating posterior fossa boost in children with high risk medulloblastorna; dosimetrically evaluating and comparing both techniques as regard target coverage and doses to organs at risk （OAR）. Methods： Twenty patients with high risk medulloblastoma were treated by 3D-CRT technique. A dosimetric comparison was done by performing two plans for the posterior fossa boost, 3D-CRT and IMRT plans, for the same patient using Eclipse planning system （version 8.6）. Results： IMRT had a better conformity index compared to 3D-CRT plans （P value of 0.000）. As for the dose homogeneity it was also better in the IMRT plans, yet it hasn＇t reached the statistical significant value. Also, doses received by the cochleae, brainstem and spinal cord were significantly less in the IMRT plans than those of 3D-CRT （P value 〈 0.05）. Conclusion： IMRT technique was clearly able to improve conformity and homogeneity index, spare the cochleae, reduce dose to the brainstem and spinal cord in comparison to 3D- CRT technique.
