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Objective:To investigate the factors affecting the therapeutic effects of stereotactic radiotherapy on primary liver cancer.Methods:The clinical data of 116 patients with primary liver cancer who received stereotactic radiotherapy in Binzhou Central Hospital from February 2018 to April 2020 were retrospectively analyzed. The factors that affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer were analyzed.Results:Stereotactic radiotherapy was effective in 85 patients, with an overall response rate of 73.28%. There were no significant differences in maximum tumor diameter, arteriovenous fistula, portal vein tumor thrombus, distant metastasis, pseudocapsule, liver function Child-Pugh grade, Barcelona clinic liver cancer staging, and the number of stereotactic radiotherapies between different patients ( χ2 = 14.71, 12.76, 19.16, 8.54, 7.30, 7.71, 9.41, 4.08, P < 0.05 or < 0.01). Maximum tumor diameter, portal vein tumor thrombus, pseudocapsule, liver function Child-Pugh grade, Barcelona clinic liver cancer staging, and the number of stereotactic radiotherapies were the independent risk factors that affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer (Wald χ2 = 3.13, 3.75, 4.16, 5.20, 3.90, 3.40, all P < 0.05). Conclusion:Many factors affect the therapeutic effects of stereotactic radiotherapy on primary liver cancer. Early identification of the high-risk factors for primary liver cancer is conducive to minimizing the risk of stereotactic radiotherapy, improving the therapeutic effects of stereotactic radiotherapy, and improving the prognosis. This study is highly innovative and scientific.
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Objective To explore the setup errors of two different position fixing techniques in radiotherapy for thoracic canc -er, and analyze and compare the accuracy and repeatability of the two different techniques .Methods Sixty four patients with thoracic cancer were selected in our hospital from December 2011 to June 2013 .All patients received radiotherapy .Patients were divided into two groups by means of random number table .Each group had 32 cases.The low-temperature thermoplastic membrane group used ther-moplastic membrane method to fix position while vacuum bag group with negative pressure fixed position by vacuum bag method .The setup errors in the right/left direction (X-axis), anterior/posterior direction (Z-axis), head/foot direction (Y-axis) and three dimen-sional directions ( I) were compared and analyzed between the two groups .Results The low-temperature thermoplastic membrane group was able to reduce the setup errors significantly in the Z-axis (1.13 ±0.33 /2.33 ±1.24, P 0.05).Conclusions Position fixing technique with low-temperature thermoplastic membrane can help to fix position in radiotherapy for thoracic cancer , reduce the setup errors in the Z-axis, and improve the setup accuracy .
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Objective To explore the effect of two different position fixing methods on position deviation of different directions and lesions in patients with lung cancer receiving radiotherapy .Methods 100 cases were randomly selected and divided into the two groups .Group A included 50 cases using thermoplastic membrane and group B included 50 cases using vacuum cushion .Position deviations of different directions and lesions of the two groups were observed and compared .Results The forward and backward directions′position deviation of group A was significantly lower than that of group B(t=3.67,P=0.00).The total position deviation of group A was significantly lower than that of group B(t=2.83,P=0.00).The position deviation in the middle of lung field of group A was significantly lower than group B(t =4.26,P=0.00).The repositioning cases of group A accounted for 30.00%(15/50)and group B accounted for 56.00%(28/50).The difference was significant (χ2 =6.90,P=0.00).Conclusion Using thermoplastic membrane as position fixing method in patients with lung cancer receiving radiotherapy can reduce position deviation .
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The operating principle of magnetron lamp-wire power of accelerator is introduced,and the operating states are analyzed including tripolar circuit,lamp-wire current protection circuit,preheating time delay circuit and power circuit.Common failures and corresponding disposals are also introduced.
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The competition in modern medical marketplace is stormy.The technical & medical equipment is the focal point of investment for the hospital.This paper introduces the operation,management and maintenance of medical electron linear accelerator,in combination with the reality of the hospital and the working experience.The close relationship between the equipment's high-use rate,low-stop rate,short-term of recovery and every step during the operation of the equipment is explicitly expounded.