Objective:To investigate the use of simple pooling and bivariate model in meta-analyses of diagnostic test accuracy (DTA) published in Chinese journals (January to November, 2014), compare the differences of results from these two models, and explore the impact of between-study variability of sensitivity and specificity on the differences. Methods:DTA meta-analyses were searched through Chi-nese Biomedical Literature Database (January to November, 2014). Details in models and data for four-fold table were extracted. Descriptive analysis was conducted to investigate the prevalence of the use of simple pooling method and bivariate model in the included literature. Data were re-analyzed with the two models respectively. Differences in the results were examined by Wilcoxon signed rank test. How the re-sults differences were affected by between-study variability of sensitivity and specificity, expressed by I2 , was explored. Results:The 55 systematic reviews, containing 58 DTA meta-analyses, were included and 25 DTA meta-analyses were eligible for re-analysis. Simple pooling was used in 50 (90. 9%) systematic reviews and bivariate model in 1 (1. 8%). The remaining 4 (7. 3%) articles used other models pooling sensitivity and specificity or pooled neither of them. Of the reviews simply pooling sensitivity and specificity, 41(82. 0%) were at the risk of wrongly using Meta-disc software. The differences in medians of sensitivity and specificity between two models were both 0. 011( P<0. 001, P=0. 031 respectively). Greater differences could be found as I2 of sensitivity or specificity became larger, especially when I2 >75%. Conclusion:Most DTA meta-analyses published in Chinese journals(January to November, 2014) combine the sensitivity and specificity by simple pooling. Meta-disc software can pool the sensitivity and specificity only through fixed-effect model, but a high proportion of authors think it can implement random-effect model. Simple pooling tends to underestimate the results compared with bivariate model. The greater the between-study variance is, the more likely the simple pooling has larger deviation. It is necessary to increase the knowledge level of statistical methods and software for meta-analyses of DTA data.

This design is a multi-point thermometry system based on single bus digital thermometer DS1820.The single bus system of multi-point measure temperature is developed with single chip computer 89C52 and circuit units for physiological signal measurement.Obtainment method of higher resolution temperature data is given.The method makes measure temperature resolution reach to 0.1?C.It is characterized by simplicity of structure,high precision and real time,and is easy to transmit by internet network.So the system has widely applications value on clinic.

Objective:To investigate mechanical properties,fluorine release behavior and bacteria inhibition effect of hydroxyapatite-improved glass ionomer cement(HA/GIC).Methods:HA/GIC was prepared with HA mass fraction of 28％.Bending strength and compressive strength of HA/GIC and GIC were measured by an universal material testing machine.Microstructure of the materials was observed by scanning microscope technique (SEM).Accumulation of fluorine release was measured by fluorine ion selective electrode.Bacterial inhibition of total bacteria and Streptococcus mutans was monitored by fluorescence in situ hybridization.Results:Bending strength,compressive strength and fluorine release accumulation of HA/GIC were significantly higher than those of GIC (P ＜ 0.05).There were many.irregular polymerized particle monomers and micro cracks within the GIC.In HA/GIC,hydroxyapatite particles were connected with original composition.Bacterial inhibition of total bacteria and Streptococcus mutans by HA/GIC was more effective than that by GIC.Conclusion:HA/GIC has perfect mechanical properties,fluorine release behavior and bacterial inhibition effect.

PBL teaching model has been adopted as one of mainstream models in the west medical education.This article,with the characteristics of medical physics,combined with the advantage of PBL,discusses how PBL teaching mode is applied to medical physics.What we have done provides a reference for the development of PBL in medical physics.

In order to meet the needs of training high-quality medical persons, combining teaching reform theory with foundational courses teaching practice, we summarize some successful experience in many respects such as construction and reformation of foundational educational system, grasping subject construction goal, bringing up and cultivating scientific researchers, improving experimental conditions. All we have done reveal that the combination of medicine and engineering is the characteristic form of development.

Objective:To investigate the clinical application value of nano-carbon tracer technology in lymph node dissection and postoperative pathological examination in laparoscopic mid-low rectal cancer resection.Methods:Fifty-two patients with mid-low rectal cancer were randomly divided into experimental group (n=27) and control group (n=25).Before surgery,the Nano-group were injected nano activated carbon suspension liquid under the mucosa.Both groups were accepted the same principles of open colorectal cancer radical surgery.The total number of lymph nodes,number of tiny lymph nodes,number of black dye and number of metastasis lymph node confirmed by pathology in the two groups were statistical analysised.Results:There were 905 pieces of lymph node seized in two groups toally,including (20.67 ± 5.751) medals in Nano-carbon group and (13.88 ±4.466) medals in control group.Lymph node number in nano carbon group was more than control group (P＜0.01).Nano-carbon group seized 113 tiny lymph nodes,significantly higher than 49 in the control group (P＜0.05).The metastasis rate of lymph node was no significant difference in the two groups (P＞0.05).Nano-carbon group seized lymph node metastasis was no significant difference in the rate of the control group (P＞0.05).Nano-carbon group seized 341 black dyed lymph nodes and 217 not black dye lymph nodes.And 67 cases of metastasis lymph nodes in Black dye lymph nodes,15 cases of metastasis lymph nodes in not the black dye lymph nodes.The metastasis rate of black dye lymph node was higher(P＜0.01).Conclusions:Nano-carbon tracer technique can guide the surgeon to accurately lymph nodes dissection during the operation,and can add to the number of lymph nodes in the postoperative surgical specimens,improve lymph nodes in patients with colorectal cancer radical seized quantity.Nano-carbon tracer technique can ensure the accuracy of the pathological staging,there was important clinical significance to lymph node dissection in Mid-low colorectal cancer,which provide an important basis for the development of postoperative adjuvant therapy programs.

Objective To evaluate the results of surgical treatment for patients with heterotaxy syndrome and cardiac anomaly.Methods From September 2008 to October 2013,34 patients with heterotaxy syndrome underwent 46 cardiac operations at Guangzhou Women and Children Medical Center.22 were male,and 12 female.Mean age at operation was 22 months (4 months to 14 year).There were right atrial isomerism 24 cases,left atrial isomerism 10 cases.Only one had a single VSD,and others were all with complex cardiac anomaly,including complete atrioventricular canal defect 26 cases,tricuspid atresia 4 cases,mitral atresia 1 case,anomalous pulmonary venous connection 18 cases,pulmonary venous stenosis 4 cases,double superior vena cava 17 cases,and interrupted hepatic portion of the inferior vena cava 5 cases.Fontan procedure was performed in 5 patients,bidirectional Glenn in 13,Kawashima in 3,central shunt in 1,atrioventricular valve replacement in 5,and pulmonary artery banding in 5.Results There were 4 died during hospitalization.The follow-up duration was 1 month to 5 years.There were 2 died.The early to middle term mortality was 17.6％ (6/34).In the same period the mortality for 103 patients without heterotaxy syndrome underwent univentricular repair was 4.8％ (5/103).There was significant statistical difference (P ＜ 0.05).Conclusion Right heart bypass operation remains the preferred palliative procedure for patients with heterotaxy syndrome,and the eraly and middle term results were satisfied.

Objective To evaluated the early and mid-term results of arterial switch operation (ASO) for patients with intramural coronary artery.Methods From September 2008 to March 2012,75 patients underwent ASO at Guangzhou Women and Children Medical Center for repair of transposition of the great arteries and Taussig-Bing anomaly.Among these patients,7patients (9.3％) had an intramural coronary artery.Mean age at operation was 2.4 months (2 days to 1 year) and mean body weight was(4.3 ±2.2) kg.The TGA and VSD in 3 cases,TGA/IVS in 2,and Taussig-Bing anomaly in 2.Among them 3 patients had an aortic arch anomaly,interruption of the aortic arch in 1 and coarctation of the aorta in 1.The individual coronary button technique was used in coronary transfer in 7 patients,of whom one patient required to unroof the intramural segment,an-other one required to unroof the intramural segment and enlarge with autologous pericardium the because of myocardial ischemia.There was 1 operative death because of low cardiac output syndrome.This patient underwent a coronary transfer combining aortic arch repair but without unroofing the stenotic intramural segment.The mortality was 14.2％.In the same period the mortality for 68 patients without an intramural coronary artery was 4.4％ (3/68).There was no statistical difference in mortalitv between the patients with and without an intramural coronary artery (P ＞ 0.05).Results 6 patients follow-up 4 to 47months.There was no late death.No intramural coronary artery obstruction was identified by cardiac computerize temography.All patients had normal ventricular function and were in NYHA class Ⅰ during follow-up.The intramural coronary artery is well known as a risk factor of ASO.Conclusion The technique of coronary transfer should be individually adapted to each anatomical situation.Individual technique for coronary transfer has excellent results.

Objective: This paper summarized the research status and progress of photodynamic therapy (PDT) and sonodynam-ic therapy (SDT), and we hope this can be a useful reference for clinics or research. Methods: In this review we expound their molecular mechanisms in detail and classify the photosensitizer and sonosensitizer, indicate their applications for the cancer treatment and summarize their new treating modes. PDT and SDT have huge potential for cancer treatment. Results: PDT and SDT have achieved a certain results, whereas there are still many problems, such as tissue oxygen content, new photosensitizer and sonosensitizer, drug dosage and mechanisms of SDT. Conclusions: PDT and SDT, which are new methods for treating cancer, have shown a good application prospect. But PDT has not been universal in clinics and SDT is still in the experiment stage.

Objective To evaluate narrow band imaging (NBI) assisted argon plasma coagulation (APC) in treatment of Barrett's esophagus (BE). Methods Suspected BE lesion was observed under white light, NBI and magnification, biopsies were taken at the site with characteristic pit pattern and capillary architecture of BE. A total of 86 patients with pathologically confirmed BE were randomly divided into NBI group (n= 42) to receive APC under NBI, or control group (n= 44) to receive APC under whit light. For APC procedure, the probe was inserted through biopsy channel to reach 1 cm beyond the endoscope tip, and was located 1-2 cm from the lesion to assure safe use. All patients were followed up with endoscopy and biopsy at 3 and 6 months after APC, respectively. Results There was no significant difference between 2 groups in effective rate of BE mucosal eradication at 3 and 6 months after APC procedure (P > 0.05). Conclusion NBI assisted APC is safe and effective in eradication of BE epithelium, in reducing procedure time and in relieving of functional gastrointestinal symptoms related with BE.