The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable_state tr...The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable_state trajectory of high dimensional nonlinear dynamic systems was got within integral space.According to international standard of rotor system vibration, energy limits of safety criterion were determined. The safety margin was calculated within a series of observing spaces by comparative positive_area criterion (CPAC) method. A quantitative example calculating safety margin for unbalance elastic rotor system was given by CPAC. The safety margin criterion proposed includes the calculation of current stability margin in engineering. This criterion is an effective method to solve quantitative calculation question of safety margin and stability margin for nonlinear dynamic systems.展开更多
Introduction: Nowadays the more accepted surgical option for treating early breast cancer is breast conserving surgery. The main challenge in this type of surgery is to get free safety margins without need of second s...Introduction: Nowadays the more accepted surgical option for treating early breast cancer is breast conserving surgery. The main challenge in this type of surgery is to get free safety margins without need of second surgical operation, so many breast surgeons have started to depend on intraoperative frozen sections to ensure free safety margins. Aim of work: To assess our policy that we prefer to depend on intraoperative frozen section analysis to get free safety margin in breast conserving surgery from the 1st surgery, and its oncologic outcome. Patients and Methods: This is a retrospective study conducted in Oncology Center—Mansoura University (OCMU), where the data of 219 patients with breast cancer, who were managed by breast conserving surgery with intraoperative frozen section analysis of the safety margins, was analyzed. Results: The intraoperative frozen section analysis of safety margin was negative from the start in 183 (83.6%) patients, while it was positive in 36 patients (16.4%). Intraoperative decision of margin re-excision was applied for 29 patients (13.2%) in order to reach negative margin, modified radical mastectomy was offered for 4 patients (1.8%), while nipple sparing mastectomy with immediate breast reconstruction using latissimus dorsi flap was offered for 3 patients (1.4%). The postoperative paraffin results were typical with intraoperative frozen section analysis results in 216 patients (98.6%) and different results were obtained in only 3 patients (1.4%) who were managed by modified radical mastectomy in a second operation. Only 4 patients had local recurrence (1.8%) during the period of follow-up duration which was ranged from 1 to 86 months with mean ± SD (22.3 ± 14.1). Conclusion: The intraoperative frozen section analysis of safety margins in breast conserving surgery has very high-rate typical results with the paraffin section analysis and it is very helpful in decreasing the rate of second surgical operation in cases of infiltrated margins. It should be used routinely in all cases of breast conserving surgery.展开更多
The length and method of measurement of the safety-margin below the rectal cancer, being of the utmost importance for its prognosis, is still under debate.The following study was designed and done for its solution.Lig...The length and method of measurement of the safety-margin below the rectal cancer, being of the utmost importance for its prognosis, is still under debate.The following study was designed and done for its solution.Light microscopic examination was done on 83 resected rectal cancer specimens to assess the extent of intramural invasion towards the anus.By use of a ruler,the distance between the lower tumour margin and the resection line or the dentate line was measured when the specimen was:l. freshly resected,2.after fixing in 10% formalin, and 3.after being mounted in sections. The measurements were compared. By the same method,the distance between the lower tumor margin and the intended resectyion line was measured immediately before resection.It was compared with the measurement immediately after the resection.In 83 rectal cancer specimens, the extent of intramural infiltration toward the anus was:≤0.5 cm in 75 cases (90.4%).≥l cm in 2 cases which showed highly malignant carcinomas.These 2 cases, however,should not have been indicated for anus-saving resection.In 46 fresh specimens,the tumor-resection line distances gave an average of 2.7 cm.After fixing in 10% formalin, they became shortened by 0.7 cm. And, mouting in sections further shortened them by another 0.5 cm,giving a total shortening of l.2 cm.The tumor-resection line distance in 7 of the 11 fresh specimens resected by the Dixon's operation was shortened,though never more than o.5 cm immediately the operation.In performin ganus-saving resection for the low rectal cancer, after full isolation the rectum and stretching it slightly,≥3 cm of the rectum distal to the lower tumor margin should be resected.A safety margin of more than 2.5 cm is necessary in the fresh specimen.If formalin fixed specimen is measured, the safety margin should be ≥2 cm.展开更多
文摘The safety margin criterion of nonlinear dynamic question of an elastic rotor system are given. A series of observing spaces were separated from integral space by resolving and polymerizing method. The stable_state trajectory of high dimensional nonlinear dynamic systems was got within integral space.According to international standard of rotor system vibration, energy limits of safety criterion were determined. The safety margin was calculated within a series of observing spaces by comparative positive_area criterion (CPAC) method. A quantitative example calculating safety margin for unbalance elastic rotor system was given by CPAC. The safety margin criterion proposed includes the calculation of current stability margin in engineering. This criterion is an effective method to solve quantitative calculation question of safety margin and stability margin for nonlinear dynamic systems.
文摘Introduction: Nowadays the more accepted surgical option for treating early breast cancer is breast conserving surgery. The main challenge in this type of surgery is to get free safety margins without need of second surgical operation, so many breast surgeons have started to depend on intraoperative frozen sections to ensure free safety margins. Aim of work: To assess our policy that we prefer to depend on intraoperative frozen section analysis to get free safety margin in breast conserving surgery from the 1st surgery, and its oncologic outcome. Patients and Methods: This is a retrospective study conducted in Oncology Center—Mansoura University (OCMU), where the data of 219 patients with breast cancer, who were managed by breast conserving surgery with intraoperative frozen section analysis of the safety margins, was analyzed. Results: The intraoperative frozen section analysis of safety margin was negative from the start in 183 (83.6%) patients, while it was positive in 36 patients (16.4%). Intraoperative decision of margin re-excision was applied for 29 patients (13.2%) in order to reach negative margin, modified radical mastectomy was offered for 4 patients (1.8%), while nipple sparing mastectomy with immediate breast reconstruction using latissimus dorsi flap was offered for 3 patients (1.4%). The postoperative paraffin results were typical with intraoperative frozen section analysis results in 216 patients (98.6%) and different results were obtained in only 3 patients (1.4%) who were managed by modified radical mastectomy in a second operation. Only 4 patients had local recurrence (1.8%) during the period of follow-up duration which was ranged from 1 to 86 months with mean ± SD (22.3 ± 14.1). Conclusion: The intraoperative frozen section analysis of safety margins in breast conserving surgery has very high-rate typical results with the paraffin section analysis and it is very helpful in decreasing the rate of second surgical operation in cases of infiltrated margins. It should be used routinely in all cases of breast conserving surgery.
文摘The length and method of measurement of the safety-margin below the rectal cancer, being of the utmost importance for its prognosis, is still under debate.The following study was designed and done for its solution.Light microscopic examination was done on 83 resected rectal cancer specimens to assess the extent of intramural invasion towards the anus.By use of a ruler,the distance between the lower tumour margin and the resection line or the dentate line was measured when the specimen was:l. freshly resected,2.after fixing in 10% formalin, and 3.after being mounted in sections. The measurements were compared. By the same method,the distance between the lower tumor margin and the intended resectyion line was measured immediately before resection.It was compared with the measurement immediately after the resection.In 83 rectal cancer specimens, the extent of intramural infiltration toward the anus was:≤0.5 cm in 75 cases (90.4%).≥l cm in 2 cases which showed highly malignant carcinomas.These 2 cases, however,should not have been indicated for anus-saving resection.In 46 fresh specimens,the tumor-resection line distances gave an average of 2.7 cm.After fixing in 10% formalin, they became shortened by 0.7 cm. And, mouting in sections further shortened them by another 0.5 cm,giving a total shortening of l.2 cm.The tumor-resection line distance in 7 of the 11 fresh specimens resected by the Dixon's operation was shortened,though never more than o.5 cm immediately the operation.In performin ganus-saving resection for the low rectal cancer, after full isolation the rectum and stretching it slightly,≥3 cm of the rectum distal to the lower tumor margin should be resected.A safety margin of more than 2.5 cm is necessary in the fresh specimen.If formalin fixed specimen is measured, the safety margin should be ≥2 cm.
