Intensity-modulated radiation therapy is widely used in the treatment of tumor,and the dose distribution highly conforms to tumor target area in three-dimension.However,the factors such as complex beam,data error,algorithm error and machine error may cause large dose deviation in intensity-modulated radiation therapy,which may lead to unnecessary radiation accident.Therefore,standing on the patients' safety point of view,dose verification is usually performed before executing the treatment plan in order to ensure the safe implementation of the treatment plan and to avoid un-planned irradiation dose.Currently,there are many tools and methods of dose verification in clinic,including point dose verification tools like finger-shaped ionization chamber and thermoluminescence dosimeter;two-dimensional dose verification tools like Mapcheck,MatriXX and films;three-dimensional dose verification tools like ArcCHECK,Delta4 and the third-party software.These common clinical dose verification methods are reviewed in this paper.

Objective To reconstruct 16?bit images of metal implants using the extended function of computed tomography ( CT) imaging, and to analyze the effect of the metal CT value on calculation of dose distribution by evaluation of metal CT values in different scanning conditions. Methods A stainless steel rod and a titanium rod were inserted in a phantom. The 12?and 16?bit images and CT value distribution of metal implants were obtained by scanning the phantom using 120 kV tube voltage and 230 mA tube current. The 16?bit images and CT value distribution of metal implants were obtained by scanning the phantom using fixed tube current ( 230 mA) with varied tube voltage ( 100, 120, and 140 kV) or fixed tube voltage ( 120 kV) with varied tube current ( 180, 230, and 280 mA) . In the Varian treatment planning system, a single?field plan and a parallel?opposed field plan were designed based on the CT images. The dose distribution was calculated and compared by the paired t test. Results The CT values of the stainless steel rod and the titanium rod were both 3 071 HU in 12?bit CT images. In 16?bit CT images;however, the CT value of the stainless steel rod was significantly larger than that of the titanium rod. There were no significant differences in CT value of 16?bit image and dose distribution in radiotherapy plan between three scanning conditions with different tube currents. Under three scanning conditions with different tube voltages, the maximum CT values were 13 568, 13 127, and 12 295 HU for the stainless steel rod and 8 420, 7 140, and 6 310 HU for the titanium rod, respectively. Conclusions High?density metal implants cannot be distinguished by 12?bit images, while the distribution of metal CT value can be obtained by 16?bit images. The dose distribution of metal implants based on 12?bit images is different from that based on 16?bit images. Changes in tube voltage cause substantial changes in the CT value for metal implants, leading to changes in dose distribution in radiotherapy. Variation of tube current within a certain range causes slight changes in metal CT value and dose distribution.

Objective To investigate the features and risk factors associated with lymph node metastasis in colorectal neuroendocrine neoplasm.Methods Clinical and pathological data of 63 patients with colorectal neuroendocrine neoplasm treated in Yinzhou People's Hospital between June 1997 to December 2012,were analyzed retrospectively.Comparisons of categorical data and univariate analysis of risk factors of lymph node metastasis were conducted by x2 test,multivariate analysis was conducted by Logistic regression analysis.Results Of the 63 patients the rate of regional lymph node metastasis was 30％ (19/63) with 58％ limited to para-intestinal lymph nodes in 11 cases,26％ limited to mesenteric lymph nodes in 5 cases,and 16％ limited to mesenteric root central lymph nodes in 3 cases.No metastasis exceeding central lymph nodes was observed.According to univariate analysis,tumor size,depth of invasion,ulceration in mucous membrane,invasion of lymphatic vessel and pathological grading suggested by WHO were related to regional lymph node metastasis (P ＜ 0.01).Multivariate regression analysis revealed that tumor size,invasion of lymphatic vessel and pathological grading were independent risk factors for lymph node metastasis in colorectal neuroendocrine neoplasm (P ＜ 0.05).Conclusions Colorectal neuroendocrine neoplasm with larger tumor size,invasion of lymphatic vessel or higher grade (G2,G3) has high risk of regional lymph node metastasis.

Objective To investigate the impact on registration accuracy with the different registration ranges of CBCT images and CT images.Methods CBCT and CT scans were performed on the of 5 patients.The registration ranges of five patients' images of abdomen,head and chest performed CBCT and CT scanning were processed with four modes.Mode 1:the registration range of CT images was larger than the registration range of CBCT images,mode 2:the registration range of CT images and CBCT images were equally,mode 3:taking a 5 cm translation of CT images range from mode 2,mode 4:The CBCT range and CT range reduced 2 cm both sides simultaneously from mode 2.Using the registration program from Insight Segmentation and Registration Toolkit (ITK) to the four modes,the Mean Square Difference (MSD) metric values of four modes after registration were compared and the relationship between mode 2 and another three modes was analyzed by paired t test.Results For the MSD metric values,mode 3 was maximum,mode 2 and 4 were minimum,and mode 1 was centered.The difference between the mode 2 and mode 4 was not statistically significant(P ＞ 0.05).The difference between the mode 2 and mode 1 was statistically significant(t =-4.586,-4.164,-5.618,P ＜ 0.05).The difference between the mode 2 and mode 3 was statistically significant(t =-6.423,-8.109,-19.601,P＜0.05).Conclusion The registration ranges of CBCT and CT images has a certain extent of influence on the accuracy of image registration.The closer the registration range of CBCT and CT is,the higher the registration accuracy is.

Background mental imagery is a multi-componential process involving different mental operations. Objective The present study investigated the subsystems of visual mental imagery processing and their interactions. Methods: Four experimental tasks were done: (1) object, the ability to generate global mental images; (2) resolution, the ability to generate vivid,high-resolution mental images; (3) transformation,the ability to mentally rotate patterns in images, and (4) spatial imagery,spatial cognition. 91 university students (77 males, 14 females) participated in this study. Results: Object task was highly correlated with resolution task, and the same the tendency was found between transformation task and spatial task. Conclusion: The results indicate there are different subsystems of visual mental imagery and corresponding operative strategies, but with strong correlation among these processes and abilities.

OBJECTIVETo explore factors affecting occupational adaptability in nurses for offering basis to increase their occupational adaptability.

METHODSFive hundred and forty-five nurses were investigated with work ability index questionnaire and occupational stress instruments.

RESULTSThere were many risk factors affecting occupational adaptability in nurses. The main variables that influenced occupational adaptability included work-overtime, mental load, social support, physical environment, and job hazards. The social support was the factor increasing the occupational adaptability of the nurses (P < 0.01, OR = 0.912). Five factors including work overtime, mental load, social support, physical environment and job hazards were introduced in the Logistic equation. The established functions were: Logit (P) = -11.357 + 1.011x(1) + 0.335x(2) - 0.076x(3) + 0.260x(4) + 0.129x(5).

CONCLUSIONThere are many risk factors affecting occupational adaptability in nurses. Relevant measures should be taken to promote the occupational adaptability in nurses to reduce the risk factors.

Adaptation, Psychological ; Adolescent ; Adult ; Humans ; Logistic Models ; Middle Aged ; Nurses ; psychology ; Occupational Health ; Risk Factors ; Social Support ; Stress, Psychological ; epidemiology ; prevention & control ; Surveys and Questionnaires ; Workload ; psychology

Objective:To explore the protective effect of puerarin on hypoxia/reoxygenation (H/R)-induced acute kidney injury(AKI)in vitro.Methods:HK-2 cells were treated with H/R for simulating ischemia reperfusion injury(IRI)in vivo. The experimental groups included control group, H/R treatment group(0/6/12/24 h), H/R 24 h + puerarin treatment group(puerarin, Pue), H/R 24 h + Pue+ 3-methyladenine(3-MA)treatment group and H/R 24 h+ 3-MA treatment group. Immunoblotting was employed for detecting the expression changes of autophagy-related proteins, CCK-8 for examining cell proliferation, electron microscopy for observing autophagosome formation and TUNEL for detecting apoptosis.Results:As compared with control group, the expression of LC3-II rose in H/R 24 h group, the expression of autophagy marker P62 declined, count of autophagosome increased, cell viability decreased and cellular inflammation occurred. Puerarin had similar effects to 3-MA. As compared with H/R 24 h group, puerarin could reverse the changes in the expression levels of LC3 and P62 induced by H/R( P<0.05). There were greater cell viability, reduced autophagosome count and lessened cell apoptosis( P<0.05). At the same time, protein expression levels of HMGB1, TLR4 and NF-κB dropped( P<0.05). Conclusions:Puerarin suppresses autophagy through HMGB1/TLR4/NF-κB axis for lessening ischemia-reperfusion injury an in vitro model.

Since the first outbreak of avian influenza A(H7N9) virus in humans was identified in 2013, there have been five seasonal epidemics observed in China. An earlier start and a steep increase in the number of humans infected with H7N9 virus was observed between September and December 2016, raising great public concern in domestic and international societies. The epidemiological characteristics of the recently reported confirmed H7N9 cases were analysed. The results suggested that although more cases were reported recently, most cases in the fifth epidemic were still highly sporadically distributed without any epidemiology links; the main characteristics remained unchanged and the genetic characteristics of virus strains that were isolated in this epidemic remained similar to earlier epidemics. Interventions included live poultry market closures in several cities that reported more H7N9 cases recently.

Objective To apply metal artifact reduction algorithm to reduce metal artifacts based on 12 bit and 16 bit CT images,and aimed to analyze the effects on CT value and dose distribution.Methods The metal implant was inserted into the phantom,and the original 12 bit CT image and original 16 bit CT image were derived from CT scanning.The images were processed using NMAR algorithm,so the corrected 12 bit image and corrected 16 bit image were obtained.A patient's CT was chosen with artificial femur,and used the NMAR algorithm to reduce metal artifacts.Furthermore,the CT values of original images and corrected images were compared and analyzed.In the planning system,dose distribution was calculated based on each image by same radiation treatment plan.The dose distribution difference of each image was compared and analyzed.Results For the 12 bit image,the CT value of metal was 3 071 HU,which was much smaller than the metal's actual CT value ll 080 HU.The metal's CT value for the 16bit image was 11 098 HU,which was very close to the actual value.The original CT images contained a lot of artifacts around the metal,resulting in a large deviation of CT values from the reference image.After NMAR correction,metal artifacts were reduced significantly,and the CT values were close to the reference images.The dose distribution of the corrected 16 bit image was closest to that of the reference image.The maximum dose deviation on the central axis was 1.8％.The difference between the 12 bit image and the reference image downstream the metal was notable,and the maximum dose deviation on the central axis was 81.6％.The X-rays passed through the artifact region in original image,the dose distribution was obviously different from the reference image,and the maximum dose deviation was 21.6％.Conclusions For the patient with metal implant,using the NAMR algorithm on the 16 bit image result in accurate CT value of CT image,so that the accurate dose distribution will be obtained.

Objective · To study the effect of inhibitor of differentiation 1 (ID1) on ocular neovascularization. Methods · The oxygen-induced retinal neovascularization (OIR), laser-induced choroidal neovascularization (CNV) and over-expression of vascular endothelial growth factor (VEGF) (Rho-VEGF) transgenic mice were established. The localization and mRNA level of ID1 in retina of OIR mice and Rho-VEGF transgenic mice were determined by immunofluorescence staining and quantitative real-time PCR. Mice deficient in ID1 (ID1-/-) were used to induce retinal neovascularization in accordance with the above three models, and to compare the changes of ID1 on the number of retinal, subretinal and choroidal neovascularization areas. In order to explore the role ID1 in neovascularization, the numbers and areas of retinal, subretinal and choroidal neovascularization in the mice models with or without ID1 deficiency were compared. Its effect on the related factors, i.e. hypoxia-inducible factor-1α (HIF-1α), VEGF and vascular endothelial growth factor receptor 1/2 (VEGFR1/2) were also observed. Results · Mice deficient in ID1 showed a significant reduction in the area of neovascularization in these three models (P＜0.05). Mice lacking ID1 showed reduced levels of HIF-1α, VEGF and VEGFR 1. Conclusion · ID1 promotes the expression of HIF-1α, VEGF and VEGFR1 in the retina and choroidal neovascularization during hypoxia and oxidative injury.