Objective To study the difgerence between the IAEA code of practice TRS-Z77 and TRS-398 in the determination of the absorbed dose to water for high-energy photon beams using several cylindrical chambers. Methods For 6 different types of cylindrical chambers,the calibration factors ND,W,Q0 in terms of absorbed dose to water were calculated from the air exposure calibration factors N,,and were compared with the ND,W,Q0 measured in European standard laboratory. Accurate measurements were performed in Varian 6 MV photon beam using 6 cylindrical chambers according to TRS-277 and TRS-398.The beam quality correction factors kQ.Q0 as well as the water absorbed doses were compared.Results For the set of chambers,the difference between ND,W,Q0 computed from Nx and ND.-.Q0 obtained in European standard laboratory was 0.13％ ～ 1.30％.The difference of beam quality correction factors for TRS-277 and TRS-398 was 0.09％ ～0.45％.The distinction of the water absorbed doses obtained according to the two different protocols was 0.27％ ～ 1.40％,and was primarily due to their different calibration factors.Conclusions The discrepancy in absorbed doses determined according to two protocols using different cylindrical chambers is clinically acceptable.However,TRS-398 allows a more convenient localization of chambers,provides a more simple formulation,and offers the reduced uncertainty in the dosimetry of radiotherapy beams.

Delicacy management proves a pressing need in cost management of medical service items in the current hospital operation.This paper first covered the methodology and system of hospital costing.It went on to describe the costing for four major medical service items in a quarter in 2011 using the activity-based costing method with the ultrasonographic section of a large hospital as an example.The outcomes were compared to the traditional costing method and the statutory pricing standards,resulting in the proposal and recommendation on reforming the costing methodology of service item pricing,and applying the activity-based costing management of medical service items in the hospital.

Objective To discuss the effect of formative evaluation for flipped classroom of college English teaching. Method We chose 180 clinical medicine undergraduates from a college and divided them equally into experimental class and control class. In the experimental class, the formative evaluation was implemented for the flipped classroom of college English teaching from September 2014 to June 2015. At the same time, the teaching in the control class was carried out according to the basic process of flipped classroom, with no formative evaluation. At the end of the experiment, the students' satisfaction survey, autonomous learning ability and English proficiency test of the two classes were finished. SAS 9.1 software was used for statistical analysis, and t test was used to compare two class measurement information and count data with chi-square test. Result ①Experimental class' satisfaction of formative assessment teaching design for flipped classroom was 94.45%, which was obviously higher than that of the control class (66.66%). The difference was statistically significant (χ2=7.94, P=0.005). (χ2=7.94,P=0.005).②The score at first, fifth dimension and the overall score of independent learning in experimental classes were respectively (55.31± 4.99)、 (53.61±4.93)、 (247.16±22.10), and they were significantly higher than those in the control class (47.18±4.23)、(45.72±4.01)、(225.92±20.78) (t=8.889, P=0.001;t=7.299, P=0.001;t=6.642,P=0.001), and other dimensions' score was also significantly higher than that in comparative classes (P<0.05). ③The pass-ing rate of CET-4, and the number of students from 505 to 544 and more than 545 fraction in the experi-mental class were respectively 79 (87.78%)、19 (21.11%)、10 (11.11%), and they were significantly higher than those in the control class 61(67.78%)、10(11.11%)、0(0). Conclusion Formative assessment can obvi-ously improve the teaching effect of flipped classroom of college English.

To explore an easily executive and conveniently generalized method with effectiveness and low costing for myopia screening at the early stage.Research was performed to testify the reasonability of using axial length/corneal radius (AL/CR) for myopia screening in children by comparing the cost between AL/CR plus vision acuity (VA) and simple VA examination.Chinese school-aged children in Yangfang school district,Beijing (n=1427,aged 6～12 years old) were randomly grouped for either pure VA examination or for VA plus AL/CR examination.Those suspicious myopic children were informed for further refractive examination.Finally,the cost from screening to definite diagnosis of refractive error was calculated.Generally,compared with VA examination,the total cost was reduced by 15.12％ and by 12.34％,respectively,in the elder group using VA plus AL/CR examination.VA plus AL/CR examination is an economical and reasonable method for screening suspicious myopia in Chinese school-aged children compared with pure VA examination.

Objective To evaluate the prognostic value of microsatellite instability (MSI) in stage Ⅱ colon cancer patients.Methods 120 stage Ⅱ colon cancer patients underwent radical resection in the Department of Colorectal Surgery,Beijing Cancer Hospital from 2000 to 2007.Tissue samples were collected and DNA was extracted for MSI determination using PCR following the Pentaplex panel.Clinical parameters were also combined and analyzed statistically to explore the association between MSI status and clinical parameters.Results The incidence of high frequency of microsatellite instability (MSI-H) was 20.8％ in these 120 stage Ⅱ colon cancer patients.There was a significant correlation between the status of MSI and tumor differentiation (x2 =9.69,P =0.021);However MSI status was demonstrated to be a prognostic factor for disease free survival or overall survival (all P ＞ 0.05).Nor was MSI status associated with tumor relapse or metastasis.Age and preoperative serum CEA level were identified as independent factors for DFS by Cox regression.Conclusion In stage Ⅱ colon cancer patients,MSI status correlates with tumor differentiation,but is not a prognostic factor.

Objective To compare the effects of remifentanil infused at different rates on median effective target plasma concentration (EC50) of propofol inhibiting responses to laryngeal mask airway (LMA) insertion and determine the optimum infusion rate of remifentanil when used for fiberoptic bronchoscopy in pediatric patients.Methods Eighty-four ASA Ⅰ or Ⅱ pediatric patients,aged 7 months-3 years,scheduled for elective fiberoptic bronchoscopy,were randomly assigned into 3 groups (n =28 each):normal saline group (group C),remifentanil infused at 3 ng· kg-1 ·min-1 group (group R1) and remifentanil infused at 5 ng· kg-1 · min-1 group (group R2).Responses to LMA insertion were defined as body movement and/or bucking during insertion.The initial target plasma concentrations of propofol were 5.2,4.8 and 4.4 μg/ml in groups C,R1 and R2,respectively.The target plasma concentration of propofol was determined by up-and-down sequential allocation.Each time the target plasma concentration increased/decreased by 0.2μg/ml.EC50 and 95 ％ confidence interval of propofol blunting responses to LMA insertion were determined by probit method.Results EC50 (95 ％ confidence interval) of propofol was 5.03 (4.92-5.12) μg/ml,4.71 (4.58-4.84) μg/rnl and 4.46 (4.20-4.94) μg/ml in groups C,R1 and R2,respectively.There was no significant difference in EC50 of propofol between groups R1 and C (P ＞ 0.05).EC50 of propofol was significantly lower in group R2 than in groups C and R1 (P ＜ 0.05).Conclusion The infusion rate of remifentanil should not be lower than 5 ng· kg-1· min-1 when combined with propofol in pediatric patients undergoing fiberoptic bronchoscopy.

Objective To explore the immune characteristic of a patient with hypogammaglobulinaemia and low natural killer(NK)cell numbers. Methods Case histories were analyzed repeatedly to grasp important characteristics of the disease. A routine blood examination and peripheral blood immunological detection was done. Complete neutrophil function test,lymphocyte proliferation ability and cytokine profile were evaluated. Results A 3-year-old boy was referred to the hospital because of fever and abdominal pain as well as partial intestinal obstruction. Laboratory examination revealed low immunoglobulin,reduced absolute numbers of B and NK cells and deficient B cell function of lower IFN-γ and IL-12 production. The patient also had mesenteric lymphadenopathy and a caecal mass with histology suggestive of ileocecal junctional tuberculosis. The patient was infected with cytomegalovirus(CMV)and fungus,which are not common in simple antibody deficiencies. The patient was followed for four years and during this period the patient had recurrent periodontitis resulting in the loss of one tooth. Conclusions Although the precise mechanism of the defect is unclear,we speculate that the case may cast new light on primary immunodeficiencies predominantly with antibody deficiency.(J Clin Pediatr,2011,29(7):601-608)

Objective To determine the best extraction process of ginkgo leaves with the total transfer rate of total flavonol glycosides and terpene lactones as the index.Methods The effects of ethanol concentration, solid-liquid ratio and extraction time on extraction process were investigated by orthogonal design method, and the contents of total flavonol glycosides and terpene lactones were detected by HPLC to calculate transfer rate.Results The optimum extraction conditions were as follows:85% ethanol refluxing and extracting for three times;the first time extracting with five-fold amount of solvent (V/W) for 3 hours;the last two times with three-fold solvent (V/W) for 2 hours.Conclusion This extraction process has the advantages of simplicity of operator, reason, energy conservation, high efficiency, and is suitable for industrial production.

Objective Investigate the clinicopathological characteristics of h?rthle cell tumors of the thyroid. Methods Sixteen cases of HCT were studied by the clinicopathological study and immunohistochemical and review of the literature. Results There were 13 cases of h?rthle cell adenomas, 5 h?rthle cell follicular carcinomas. Immunostains showed that almost all benign and malignant HCT expressed TG, vimentin, S-100 protein. Conclusions HCT is a potential malignant tumor with a defined pathologic feature. It should be follow up for a longer time to their biological behaviors. To distinguish between the benign and the malignant depends on traditional encapsulation, and whether there is a blood vessel invasion or metastasis.

OBJECTIVE:To study the apoptosis of human leukemic cells induced by Dihydroartemisinin and its molecular mechanism.METHODS:Human leukemia K562 cells were treated by Dihydroartemisinin.The inhibitory effect on cell proliferation was assayed by MTT.Fluorescence microscopy was applied to observe the presence of apoptosis.The expression of caspase-3 was assayed with reverse transcription-polymerase chain reaction(RT-PCR).Levels of mitochondrial and cytoplasmic cytochrome C were determined using Western blot.RESULTS:After treatment with Dihydroartemisinin for 48 hours,the IC50 values of human leukemia K562 cells were 8? 10-5mol? L-1 detected at a wavelength of 570nm by MTT.Distinct morphology changes of cell apoptosis such as karyopyknosis and conglomeration were observed by Hoechst33342/PI staining.RT-PCR assay showed the expression of Caspase-3.Western-blot detection showed the decrease of mitochondrial cytochrome C concentration but the positive expression of cytoplasmic cytochrome C concentration.CONCLUSION:Dihydroartemisinin could inhibit proliferation and induce apoptosis of human leakemic K562 cells,this may partially attributed to the promotion of the delivery of cyt-c and the activation of caspase-3.