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Objective To study the effect of different atorvastatin doses on contrast-induced nephropathy (CIN) and the role of neutrophil gelatinase-associated lipocalin (NGAL) in early diagnosis of CIN after PCI.Methods Two hundred and twelve patients admitted to our hospital for PCI from June 2015 to January 2017 were divided into high atorvastatin dose treatment group as group A (n=108) and conventional atorvastatin dose treatment group as group B (n=104).They underwent coronary arteriography and PCI.Their serum creatinine and urinary NGAL levels were measured before and at 4,24,48,72 h respectively after coronary arteriography and PCI.The role of urinary NGAL level in early diagnosis of CIN was analyzed according to its ROC curve.Results CIN occurred in 6 patients of group A and in 19 patients of group B with an incidence of 5.6％ and 18.3％ respectively (P=0.012).The urinary NGAL level was significantly higher in two groups at 4,24,48,72 h respectively after coronary arteriography and PCI than before coronary arteriography and PCI,reached its peak at 72 h,and was significantly higher in group B than in group A (P＜0.05).The area under the ROC curve was 0.917,0.919,0.928,0.953 respectively at 4,24,48,72 h after coronary arteriography and PCI.The sensitivity and specificity of urinary NGAL in early diagnosis of CIN were 92.10％ and 100.00％ respectively.Conclusion High atorvastatin dose treatment can reduce the occurrence of CIN.Urinary NGAL level can indicate the change of renal function earlier than serum creatinine level after PCI,and can thus be used as an early predictor of CIN.
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Objective To introduce and evaluate the dosimetric characteristics of a GyroKnife cobalt-60 system for radiosurgery.Methods0.015 cm3 and 0.600 cm3 ionization chamber,EDR2 film and semiconductor dosimeter were used to measure the dose rate of center point for the four collimators.The diameter of the four collimators were 5 mm,12 mm,30 mm and 50 mm,respectively.0.015 cm3 ionization chamber was used to test the dose-time linear relationship and dose stability.0.015 cm3 ionization chamber and semiconductor was used to measure the dose error of phantom between treatment planning system (TPS)calculation and measurement.The film was used to measure the error of TPS calculation isodose lines width.ResultsThe results from the four measurement methods have no significant difference for the collimator 50 mm.But for collimator 5 mm great discrepancy appeared.The error between calculation by TPS and the measurement by semiconductor was biggest and the value was 4.8％.Most of the error was within 3.0％.The error of the 50％ isodose line along x-axis was biggest and the value was 4.9 mm,others are all within 2.0 mm.ConclusionThe dosimetric character of this system is suitable for stereotactic radiotherapy.
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Objective To introduce and evaluate the characteristics of a GyroKnife Digital Cobalt-60 System for stereotactic radiotherapy and radiosurgery in mechanical aspect.Methods To test the radiation safety,the dose rate required for radiation protection was measured by using an ionization survey meter ( Inovision Model 451 B,Cleveland,OH ).Micrometer was used to verify the accuracy of the table in movement and protractor to verify the rotation movement range.The 160 mm diameter polystyrene spherical phantom and film were used in measurement of the radiation Full Width at Half Maximum.And the difference between radiation isocenter and mechanical isocenter was also verified.Results Clinical requirement in radiation protection was met.The maximum error of table movement accuracy was 0.2 cm at Z axis; the maximum error of gantry movement accuracy was 0.1°.For all the collimators,radiation Full Width at Half Maximum ( FWHM ) was 2.55,5.40,10.50,and 18.55 mm and average penumbra was 5.0,12.4,30.1,and 51.5 mm,respectively.The maximum difference between mechanical center and radiation center was 1.41 mm.Conclusions Stereotactic radiotherapy and radiosurgery has good mechanical characteristics and is suitable clinic applications.
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Objective To study the effect of different dose fractionation on overall survival in patients with limited-stage small cell lung cancer (LS-SCLC). Methods LS-SCLC patients treated with radical combined chemotherapy and radiotherapy (RT) between January 2001 and Dec 2007 were analyzed retrospectively. According to the dose fractionation schemes, patients were divided into three groups:conventional fractionated RT (1. 8 -2.0 Gy,once daily), hyperfractionated RT (1.4 Gy, twice daily) and hypofractionated RT (2. 5 Gy,once daily). Overall survival, disease free survival and pattern of failures of the three groups were compared. A total of 177 patients were enrolled, including 63 patients in conventional fractionated RT group, 79 in hyperfractionated RT group and 35 in hypofractionated RT group. Results The overall follow-up rate was 96. 6%. The patient numbers with follow-up of more than 2 and 5 years were 153 and 92, respectively. The median survival time of the entire group was 22. 4 months, and the 2-and 5-year survival rates were 43.4% and 23. 5%, respectively. The 2-year survival rates for three groups were 31%, 46% and 59% (x2 =7.94,P=0.019), respectively. The 2-year disease free survival for three groups were 20%, 31% and 40% ( x2 = 4. 86, P = 0. 088 ), respectively. In the pairwise comparisons,patients in hypofractionated RT group have better survival than those in conventional fractionated RT group ( x2 = 7. 81, P = 0. 005 ), the effect of hyperfractionated RT group lies between the hypo-and the conventional fractionated RT groups, but no significant differences were detected ( x2 = 2. 31, P = 0. 128; x2 = 2. 95, P =0. 086). The mildest side effect was found in the hypofractionated RT group. No statistically significant differences were found in the patterns of first failure. Conclusion The hypofractionated RT scheme showed potential survival benefits for patients with LS-SCLC and should be considered in the setting of randomized clinical trials.