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0bjective To study the angular dependence of optically stimulated luminescent dosimeter (OSLD) with solid phantoms under SSDL radiation level 60Co radiation field, and to discuss the possibility of OSLD in volumetric modulated arc therapy (VMAT) and other rotating irradiation dose audit. Methods OSLDs were embedded in the two phantoms with the same size and material, respectively. The phantom 1 was set to make the first OSLD perpendicular to the beam, and the phantom 2 was set to make the second OSLD parallel to the beam. The OSLDs were irradiated at 8 angles: 0°, 45°, 90°, 135°, 180°, −45°, −90, −135°. The counts of the OSLSs were read and the response of each angle which normalized to 0° were calculated. Results When the OSLDs are perpendicular to the beam, the angular response is between −6.76% ～ +1.5%, with the maximum angular dependence at 90° and −90°. When the OSLDs are parallel to the beam, the angular response is between −1.74%～+1.67%, below 2%. Conclusion It is better to correct the sensitivity of dosimeters by Element Correction Factors (ECF) for dose audit. Under the condition of rotating irradiation, OSLD shoud be set parallel to the beam, which can better reduce the influence of angular dependence and facilitate further application research of VMAT dose audit.
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Objective:To estimate the induced radioactive 56Mn and its level of iron in heavy concrete shielding wall due to neutron activation during tumor proton therapy. Methods:A Geant4 program was adopted to build the model of a heavy concrete shielding wall in a proton therapy room, simulate secondary neutrons generated by 245 MeV proton beam irradiating water phantom. The statistical distribution of radionuclide 56Mn in shielding wall was calculated. The shielding wall was layered every 10 cm thickness, the dose equivalent rate of radionuclide 56Mn in the first three shielding walls was calculated. Results:Under the maximum beam irradiation conditions (1.872 × 10 10), the number of radionuclide 56Mn in the first three layers of shielding walls are 3.10×10 8, 1.60×10 8, 9.33×10 8. The ambient dose equivalent rate at a distance of 1 m from the treatment room are 2.13×10 -3, 8.82×10 -4, 9.10×10 -4 μSv/h, and the total ambient dose equivalent rate for the first three layers was 3.92× 10 -3 μSv/h. Conclusions:During proton therapy, the shielded walls near the central axis of the beam produce more induced radioactivity. The induced radioactivity produced by the neutron-activated iron element at the ahead of the shielding wall is the strongest, and decreases exponentially as the thickness of the shield wall increases.The induced radioactivity in front of the shielding wall of proton therapy room should be concerned.
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Objective To compare the ultrafine chest drainage tube with traditional thick hose as lower tube after uniport thoracoscope pulmonary nodules resection(segmentectomy,lobectomy) and evaluate its efficacy and safety.Methods Ultrafine chest drainage tube was applied in 55 patients underwent uniport thoracoscopy pulmonary resection,and traditional thick closed drainage hose was applied in another 55 patients in the same period as the control group.Postoperative drainage quantity,drainage time,pain score and incision healing between two group were compared.Results No statistically difference was found in two groups at thoracic drainage quantity on 1 day,2 days postoperative and total drainage time.But statistically difference was found in thoracic drainage quantity on 3 days postoperative,pain score and incision healing(P ＜0.05).Conclusion Ultrafine chest drainage tube has little trauma,definite clinical effect and can be easily accepted by patients.
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Objective To establish a new method to analyze the position accuracy of multileaf collimator (MLC) in the dynamic mode.Methods The MLC test sequence was created in a field,where intentional leaf positional errors ranging from 0.1 to 1 mm per centimeter were introduced.In order to establish the relationship between the ion chamber readings and leaf position,whose slope indicated the leaf position error per centimeter,a two-dimensional ion chamber array was used to measure absorbed dose while leaves were moving at dose rates of 100,300 and 600 MU/min,respectively.For routine test,leaf position error was easily found via dose profile in y direction of the field created by dynamic leaves,where the position error could be quantitatively calculated as the slope of absorbed dose line of x direction of the same field.Results The error of 0.2 mm or more per centimeter was obviously shown through y dose profile.The calibration curve was linear at different dose rates.At 600 MU/min,a 0.1 mm leaf position error corresponded to a slope variation of 0.74％,and the differences between the tested errors and the introduced errors were within 0.1 mm.Conclusions The simple and reliable method is helpful to establish the intensity modulated radiation therapy (IMRT) quality control (QC) system.
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Objective The incidence of complications after esophageal cancer surgery is relatively high.The purpose of this paper was to explore the feasibility of combined thoraco-laparoscopy surgical treatment for senile esophageal cancer(over 70 years old).Methods A total of 526 esophageal cancer cases were retrospectively analyzed in this study.The operative procedures was esophageal carcinoma resection surgery and thoracic and abdominal lymphadenectomy which were operated through video-assisted by thoracoscope and laparoscopic From January 2010 to June 2014 in the Union Hospital of Fujian Medical University,divided into aged groups(≥70 years old,n =132) and non-aged group(＜ 70 years old,n =394).Statistical analysis was carried on the rate of two groups of preoperative risk factors(hypertension,diabetes,cardiac insufficiency,pulmonary insufficiency,cerebral infarction),surgical trauma and the number of lymph node dissection (laryngeal recurrent nerve injury,operation time,intraoperative blood loss),postoperative complications(cardiac complications,chylothorax,pulmonary complications,anastomotic fistula,poor healing of the incision,intrathoracic stomach atony),postoperative recovery and early postoperative mortality.Results Preoperative risk factors:the prevalence of the aged group with hypertension,cerebral infarction,cardiac insufficiency,and pulmonary insufficiency was significantly higher than the non-aged group (P ＜ 0.05) but diabetes (P ＞ 0.05).Surgical trauma and the number of lymph node dissection:no significant difference (P ＞ 0.05).Postoperative complications:the aged group was higher in the incidence of pulmonary complications and cardiac complications than the other (P ＜ 0.05) ; but the chylothorax,anastomotic fistula and poor healing of incision,intrathoracic stomach atony in the two groups seemed no significant difference(P ＞ 0.05).Furthermore,pulmonary complications were highest in the all complications,significantly higher than the others in both groups.Postoperative recovery:significant difference existed in postoperative hospitalization days,the aged group was obviously longer than the non-age groups.Early postoperative mortality rates in the two groups had no significant difference.Conclusion The aged patiences had a higher prevalence in the preoperative risk factors and so was the cardiac complications as well as pulmonary complications among the postoperative complications.However the combined thoraco-laparoscopy in the surgical treatment of elderly patients with esophageal cancer is safe and feasible.
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Objective The new lung cancer TNM staging for T staging the new grading.The aim of this study was to investigate the relationship between the T staging and grading of the Seventh Edition and lymph node metastasis of lung cancer.Methods In 513 cases of non-small cell lung cancer primary tumor size and lymph node metastasis were analyzed,and explore the situation of different size,lymph node metastasis in primary tumors.To analyse the collected data with SPSS software.Results The total lymph node metastatic rates in tumor diameter biggest ≤2 cm(T1a) 、2 cm ＜ ～ ≤3 cm(T1b) 、3 cm ＜ ～ ≤5 cm (T2a) 、5 cm ＜ ～ ≤7 cm(T2b) 、＞ 7 cm(T3) were 14.47％ 、28.89％ 、37.59％ 、36.37％ 、37.89％.The lymph node metastatic rate of T1a was significantly different,compared with T1b 、T2a 、T2b and T3,respectively.There were no differences between every two groups of T1b,T2a,T2b and T3.The N1 metastaic rates of T1a 、T1b 、T2a 、T2b 、T3 were compared by chi-square(P ＜0.05),The lymph node metastatic rates of T1a and T2a (P =0.001),T1a and T2b (P =0.024).The N2 metastaic rates of T1a 、T1b 、T2a 、T2b 、T3 were compared by chi-square(P ＜0.05),The lymph node metastatic rate of T 1 a was significantly different,compared with T1b 、T2a and T2b,respectively.The lymph node metastatic rate of T1 b was significantly different,compared with T2a 、T2b and T3,respectively.Conclusion The new T staging of tumor the size of the new classification is associated with lymph node metastasis rate,especially in N2.low T la lymph node metastasis rate.
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Objective To establish a method for determining the content of Naringin and Hesperidin in Zengshi Keli by HPLC. Methods The Kromasil C18 column with acetonitrile-water-phosphoric acid (20∶80∶0.02) as the mobile phase was used. The flow rate was 1.0 mL/min, the detective wavelength was 283 nm, the temperature of column is 35 ℃. Results The calibration curve were linear in the range of 0.178 5～0.892 5 ?g for Naringin and 0.073 68～0.368 4 ?g for Hesperidin (r=0.999 9) respectively. The average recovery was 97.24% (RSD=1.21%) and 96.95% (RSD=1.49%) respectively. Conclusion The method was simple, accurate, reproducible and can be used for quality control of Zengshi Keli.
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Objective To establish a simple,rapid,accurate and practical method for determination of chloride in drinking water by chloride ion-selective electrode.Methods The chlorine ion-selective electrode was used as indicator electrode and type217saturated calomel electrode of the double salt bridge(the lower salt bridge was filled with a solution of0.1mol/L potassium nitrate)was used as reference electrode.The contents of chloride in water were calculated using the calibration curve method in the electrolyte containing0.1mol/L potassium nitrate.Results The linear range of the method was10 -5 -10 0 mol/L and the best lin ear range was10 -4 -10 -1 mol/L with r=0.9999and the slope=53.5?0.667.The detection limit,recovery rate and coefficient of variation(CV)were0.3545mg /L,94.2%-102.2%(mean98.1%)and2.8%respectively.The suitable pH for the determination of the method was2-10.In the solution containing3.545mg/L chloride,50times more BrO -3 ,NO -2 ,CH 3 COO - ,SO 42- ,F - ,CrO 42- and10times more CO 32- could not interfere with the detection,but Br - and I - were interfering factors.The re-sults obtained by the chlorine ion-selective electrode method and the national standard determination method showed no statistic differences.Conclusion The method was easy to operate,rapid,accurate and suitable for determination of chloride in water.
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Objective To establish a method for determination of lead in cosmetics. Methods Samples were digested. The lead content was detected by isochronous mercury-plating method with the condition of lead cation being enriched for 40 s at -1.20V(vs. SCE). Results The stripping potential peak of lead appeared at - 0. 20 V( vs. SCE) . The detection limit was 0.03 jug Pb. Six parallel determinations of a sample were done with the mean of 3.574mg/ kg and the relative standard deviation of 4. 1% . Recovery rates obtained by standard addition test ranged from 90% -100.5% . Conclusion The method is suitable for detecting lead in cosmetics.
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OBJECTIVE:To establish the Microbial limit test(MLT) for Danggui funing drop pills.METHODS:The recovery rates of 5 tested strains treated by Danggui funing drop pills were detected and the MLT method for the control bacteria was validated.RESULTS: Danggui funing drop pills exhibited strong inhibitory effect on staphylococcus aureus and bacillus subtilis,but showed no effect on escherichia coli,candida albicans and aspergillus niger.CONCLUSION: By membrane-filter procedure,the antibacterial effect of Danggui funing drop pills can be eliminated and the bacterial count can be conducted;however,by routine method,the test of control bacteria is feasible.