The paper presented the principles and references for identifying services of the primary health care at townships and villages in Beijing, and proposed the screening criteria for primary health care package in rural Beijing. Studies made have identified the screening results for the package applicable to both townships and villages in Beijing, along with analysis for the rationale, applicability and operability of the package. Moreover, it probed into the assurance conditions for offering primary health care as a reference for other regions in the country.

Objective To explore the clinical efficacy of CT-Guided radioactive 125I seed implantation in treating retroperitoneal lymph node metastases. Methods Eighteen patients with retroperitoneal lymph node metastases (20 lesions in total) received CT-guided radioactive 125I seed implantation. Treatment planning system (TPS) was used to formulate the therapeutic protocol. The radioactive activity of 125I particle ranged from 1.11 × 107-2.96 × 107 Bq (0.3-0.8 mCi) and the matched peripheral dose (MPD) was 60 -100 Gy. Postoperative dosimetry was routinely performed for all the patients in one week. Postoperative D90 (90%dose received by target volume) was 53 -107 Gy. The patient’s clinical benefit response (CBR), two-month local tumor control rate and one-year survival rate were evaluated, and the complications were recorded. Results All the patients were followed up for 2 -15 months with a median time of 5 months. The one-year survival rate was 22.2%. The clinical benefit rate, overall effective rate and two-month local tumor control rate were 72.2%, 70.0% and 90.0% respectively. No serious complications occurred in all patients. Conclusion For the treatment of retroperitoneal lymph node metastases, CT-guided radioactive 125I seed implantation is mini-invasive with satisfactory short-term effect and fewer complications. Therefore, this technique is a relatively safe therapeutic means.

Objective To discuss the commonly used puncturing approaches in CT-guided 125I seed implantation for lumbar lymph node metastases in order to provide safe and reliable technical guidance for clinical practice.Methods Under CT guidance,125I seed implantation for lumbar lymph node metastases was performed.According to different locations of metastatic lymphadenopathy (left waist,right waist or middle waist),the corresponding puncture route and implantation method were adopted.Meanwhile,different puncturing approach was designed in order to avoid damage to vital organs.Results For the performance of 125I seed implantation for the lymphadenopathy located at the left waist,right waist and middle waist,the commonly used puncturing approaches were percutaneous transthoracic lumboiliac costal muscle method (i.e.back approach),trans-hepatic trans-duodenal method (i.e.lateral approach) or back approach method,and trans-mesenteric approach together with coaxial needle method (i.e.anterior approach) respectively.Conclusion It is clinically feasible to use different puncturing approaches in performing 125I seed implantation for lumbar lymph node metastases,the suitable puncturing approach can ensure a successful and safe operation.

Objective To evaluate the safety and efficacy of CT-guided radioactive 125I seed implantation in treating retroperitoneal lymph node metastasis due to recurrent cervical cancer after radiotherapy.Methods A total of 10 patients with retroperitoneal lymph node metastasis (12 lesions in total)due to recurrent cervical cancer after radiotherapy,who were treated with CT-guided 125I seed implantation during the periodfrom November 2011 to October 2015,were included in this study.The diameters,that were perpendicular to each other,of the involved lymph nodesranged from 1.7 cm×1 cm to 6.5 cm×5 cm,the diameter of 6 involved lymph nodes (50％) was ＜5.0 cm and the diameter of other 6 involved lymph nodes (50％) was ≥5.0 cm.With the help of treatment planning system for brachytherapy,the source distribution was formulated.Under CT guidance,the 125l seedswith the activity of 0.3-0.7 mCi were implanted.Postoperative validation showed that D90 (90％ minimum prescription dose received by the target volume) was 36-110 Gy (median 59 Gy).After the treatment,the changes in lesion size,pain relief and complications were recorded.Results The 10 patients were followed up for 4.3-16.1 months,the median follow-up time was 9.7 months.The 2-month local control rate and the 2-month effective rate were 100％ and 58.3％,respectively.The 2-month,6-month and 12-month survival rates were 100％,66.7％ and 58.3％,respectively.The median survival time was 12.1 months.One patient (10％) died of gastrointestinal bleeding at five months after treatment,six patients (60％) died of distant metastases,three patients (30％) survived withno evidence of local recurrence.No major complications such as massive hemorrhage,intestinal infection,bone marrow suppression or other 125I seed-related complications occurred.Conclusion For the treatment of retroperitoneal lymph node metastasis due to recurrent cervical cancer after radiotherapy,CT-guided radioactive 125I seed implantation has satisfactory short-term curative effect,and this technique is safe and feasible.

Objective To investigate the imaging features of hippocampus and entorhinal cortex in the normal,mild cognitive impairment(MCI) and Alzheimer's disease (AD),and explore the value of diagnosing MCI and AD by using the method of MRI measuring the volume of hippocampus and entorhinal cortex.Method One hundred and twenty-two people including 42 cases of MCI,38 cases of AD,and 42 cases of noroal cognition(NC) were selected as our subjects from health examination persons both in hospital and outpatient service.All were performed general examination and neuropsychological scale evaluation.The volume of hippocampus and entorhinal cortex were measured by using MRI.The correlation between the volumetric changes of hippocampus and entorhinal cortex with scores of mini-mental state examination (MMSE) and Montreal Cognitive Assessment(MoCA) was analyzed.Results The volume of hippocampus and entorhinal cortex in the MCI group,AD group and NC group were (6.29 ± 1.13)cm3 and (2.71 ± 0.51) cm3,(6.27 ± 1.11) cm3 and (2.09 ±0.68) cm3,(7.01 ±0.92) cm3 and (3.12 ±0.34) cm3 respectively.The volume of MCI group was obviously smaller than that of NC group (P ＜ 0.05).The volume of AD group was smaller than that of NC group(P ＜0.01).The volume of AD group was obviously smaller than that of MCI group(P ＜0.01).There was positive correlation between hippocampus volume,the volume of entorhinal cortex and MMSE scores (r =0.770,0.811 ; P ＜ 0.01).Meanwhile,hippocampal volume,volume of entorhinal cortex were positive correlated with MoCA (r =0.810,0.842; P ＜ 0.01).Conclusion The atrophy of entorhinal cortex and hippocampus is closely related to cognitive disorder.The MRI measuring of the volume of entorhinal cortex and hippocampus has a potential value in diagnosing and distinguishing of MCI and NC.

Intestinal mucosal mechanical barrier is one of the most important structure to maintain the body homeostasis.The occurrences of inflammatory bowel disease,necrotizing enterocolitis and poor prognosis of patients with obstructive jaundice are closely related to the damage of the mucosal barrier function.Long-term high fat diet and obstructive jaundice can cause the abnormality of bile acids metabolism.These pathological conditions are often associated with the destruction of intestinal mucosal barrier function.So the correlations between abnormal bile metabolism and intestinal mucosal mechanical barrier function have aroused interests of many researchers.They found that bile acids the important component of bile are closely related to the intestinal barrier function.The paper reviewed the recent articles and summarized the mechanisms of the deficiency of bile acids,excessive bile acids and abnormal bile acids composition damaging the intestinal mucosal barrier function.It will provide reference for the new fields of study,prevention of the toxic effects of bile acids and the improvement of the prognosis of patients.

Objective To study the dosimetric effect of two source patterns, including equal spacing and peripheral dense intermediate sparse by assuming a tumor shrinking speed of 20%per month after 125 I seed implantation. Methods A virtual cylindrical tumor with 4 cm in height and 5 cm in diameter was contoured on a three-dimensional treatment planning system ( TPS ) . Two groups of preoperative plans were made with 1. 85 × 107 Bq 125 I seeds using two source patterns respectively. It was assumed that the tumor height was unchanged, while the diameter of tumor would decrease at a speed of 20%per month, and the locations of seeds would concentrate towards the tumor core. The 90%target volume dose ( D90 ) , the ratio of 90%isodose volume over the target volume ( V90 ) , and the ratio of 150%isodose volume over the target volume (V150) were calculated at 0, 1, 2, 3 months after 125I implantation respectively. Results In equal spacing group, 85 seeds were implanted. The values of D90 were 126. 20, 130. 41, 133. 82 and 139. 48 Gy after 0, 1, 2 and 3 months respectively. The values of V90 were 97. 0%, 98. 1%, 99. 3%and 100%, while those of V150 were 70. 2%, 69. 9%, 71. 1% and 71. 5%. The dense in-periphery and sparse-in the middle group was loaded with 75 seeds. The D90 values were 126. 46, 125. 41, 123. 50 and 128. 83 Gy, the V9095. 2%, 95. 7%, 94. 9%and 97. 6%, and the V15052. 8%, 60. 4%, 62. 7%and 59. 3%after 0, 1, 2 and 3 months, respectiviely. Conclusions When the tumor diameter reduces at a rate of 20%per month after 125 I seed implantation, the expected tumor dose absorption will gradually increase using the equal spacing sources pattern. However, the expected dose does not vary withsource distribution of dense-in the-surrounding and sparse-in-middle, which also reduces high dose volume more than the equal spacing pattern.

As a standard method for early stage prostate cancer, 125Ⅰ seed implantations are used widely in America. Although there are guidelines from American Brachytherapy Society and American Association of Physicists in Medicine, some hospitals still cannot implant the seeds properly according to the guidelines. Complications were observed inevitably. The medical events about seeds implantation in America from 2002 were investigated and the reasons were analyzed in this paper. Additionally, some solutions were given to avoid the medical events, so that the practitioners in China can learn from it and make sure the 125Ⅰ seeds implantation can be developed healthily and smoothly.

Objective To discuss the necessity and feasibility of intraoperative use of treatment planning system (TPS) to make real-time planning for the treatment of retroperitoneal metastatic carcinoma with CT-guided 125I seed brachytherapy.Methods The clinical data of 20 patients with retroperitoneal lymph node metastases,who received CT-guided 125I seed brachytherapy during the period from January 2013 to December 2015,were retrospectively analyzed.The patients were divided into group A (n=10) and group B (n=10).The intraoperative TPS was employed to formulate the real-time planning for the patients of group A,while real-time planning was not adopted for the patients of group B.The quality verification of preoperative planning and postoperative effect was conducted for the patients of both groups.Comparing the preoperative and postoperative absorbed dose,the minimum absorbed dose (D90) error percentage of 90％ target volume,the error percentage of the covered volume by 90％ prescription dose to the target volume (V90),the error percentage of the covered volume by 100％ prescription dose to the target volume (V100),and the error percentage of the covered volume by 150％ prescription dose to the target volume (V150) were calculated in all patients of both groups,and the results were statistically analyzed.Results The mean error percentage of D90,V90,V100,V150 in group A were (-1.30±6.80) Gy,(-0.60±2.10)％,(-0.47±2.70)％ and (89.60±282.00)％ respectively,which in group B were (-9.33±46) Gy,(11.50±13.7)％,(-13.40±15.90)％ and (10.37±2.00)％ respectively.The differences in the error percentage of D90,V90 and V100 between group A and group B were statistically significant (P＜0.05 in all),while no statistically significant difference in the error percentage of V150 existed between group A and group B (P＞0.05).Conclusion The use of intraoperative TPS real-time planning can significantly improve the consistency of target region dose before and after seed implantation and make the dose distribution more reasonable,which is of great value for the standardization of CT-guided 125I seed brachytherapy of retroperitoneal lymph node metastases.

Objective: The mitotic count of gastrointestinal stromal tumors (GIST) is closely associated with the risk of planting and metastasis. The purpose of this study was to develop a predictive model for the mitotic index of local primary GIST, based on deep learning algorithm. Materials and Methods: Abdominal contrast-enhanced CT images of 148 pathologically confirmed GIST cases were retrospectively collected for the development of a deep learning classification algorithm. The areas of GIST masses on the CT images were retrospectively labelled by an experienced radiologist. The postoperative pathological mitotic count was considered as the gold standard (high mitotic count, > 5/50 high-power fields [HPFs]; low mitotic count, ≤ 5/50 HPFs). A binary classification model was trained on the basis of the VGG16 convolutional neural network, using the CT images with the training set (n = 108), validation set (n = 20), and the test set (n = 20). The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated at both, the image level and the patient level. The receiver operating characteristic curves were generated on the basis of the model prediction results and the area under curves (AUCs) were calculated. The risk categories of the tumors were predicted according to the Armed Forces Institute of Pathology criteria. Results: At the image level, the classification prediction results of the mitotic counts in the test cohort were as follows:sensitivity 85.7% (95% confidence interval [CI]: 0.834–0.877), specificity 67.5% (95% CI: 0.636–0.712), PPV 82.1% (95% CI: 0.797–0.843), NPV 73.0% (95% CI: 0.691–0.766), and AUC 0.771 (95% CI: 0.750–0.791). At the patient level, the classification prediction results in the test cohort were as follows: sensitivity 90.0% (95% CI: 0.541–0.995), specificity 70.0% (95% CI: 0.354–0.919), PPV 75.0% (95% CI: 0.428–0.933), NPV 87.5% (95% CI: 0.467–0.993), and AUC 0.800 (95% CI: 0.563–0.943). Conclusion We developed and preliminarily verified the GIST mitotic count binary prediction model, based on the VGG convolutional neural network. The model displayed a good predictive performance.