Objective:To analyze the change rules of quantitative parameters of magnetic resonance-perfusion weighted imaging (MR-PWI) in cynomolgus monkeys with different degrees of liver fibrosis, and to explore the best parameter of MR-PWI in evaluating the severity of liver fibrosis.Methods:Liver fibrosis models of twenty-two cynomolgus monkeys were successfully established by subcutaneous injection of carbon tetrachloride and feeding with high-fat food. Among them, 15 cynomolgus monkeys developed into early liver cirrhosis (stage S4 of liver fibrosis). Compatibility group design was adopted, the comparative study on MR-PWI of exchange double blood supply model of liver was carried out in these 15 cynomolgus monkeys with a complete development process of liver fibrosis. The quantitative parameters of MR-PWI included endothelial transfer constant ( ktrans), reflux rate constant ( kep), extravascular extracellular space fractional volume ( ve), fractional plasma volume ( vp) and hepatic artery perfusion index (HPI). The change rules of the above parameters and their correlation with the severity of hepatic fibrosis were analyzed. The best parameter of MR-PWI was explored. Compatibility group design (randomized block design), analysis of variance, SNK- q test, Spearman rank correlation analysis and receiver operating characteristic (ROC) curve analysis were used for statistical analysis. Results:ktrans and kep of MR-PWI of cynomolgus monkeys decreased along with the progress of hepatic fibrosis, and the differences were statistically significant ( F=685.228, 99.718, both P<0.01). There were statistically significant differences between each stage of hepatic fibrosis (S1 to S4) and normal liver tissue (S0) ((0.527±0.038), (0.479±0.035), (0.432±0.032) and (0.387±0.031) mL/min vs.(0.584±0.044) mL/min, all P<0.01; (2.193±0.307), (1.997±0.301), (1.624±0.174) and (1.532±0.130) mL/min vs. (2.565±0.482) mL/min, all P<0.01). There were statistically significant in ktrans and kep between stage S3, S4 severe liver fibrosis and stage S1 mild liver fibrosis, stage S2 moderate liver fibrosis (all P<0.01), however there were no statistically significant differences between stage S3 and stage S4 liver fibrosis, between stage S1 and stage S2 liver fibrosis (all P>0.05). Along with the development of the severity of liver fibrosis, HPIs increased gradually, and the differences were statistically significant ( F=839.883, P<0.01). The HPIs of stage S0 to S4 were 0.244±0.022, 0.317±0.035, 0.421±0.046, 0.546±0.043 and 0.651±0.058, respectively, and there were statistically significant differences between groups (all P<0.01). Along with the progression of the severity of liver fibrosis, vp decreased while ve increased gradually, but there were no statistically significant differences among groups (all P>0.05). The results of Spearman rank correlation analysis indicated that ktrans and kep were negatively correlated with the severity of liver fibrosis ( rs=-0.875 and -0.797, both P<0.01), however HPI was positively correlated with the severity of liver fibrosis ( rs=0.959, P<0.01). The results of ROC curve analysis showed that area under curves (AUCs) of ktrans, kep and HPI in the diagnosis of early cirrhosis were 0.852 (95% CI 0.767 to 0.937), 0.799 (95% CI 0.700 to 0.897) and 0.967 (95% CI 0.932 to 1.002), respectively. The best cut-off values were 0.395 mL/min, 1.561 mL/min and 0.590, respectively. The sensitivity was 86.7%, 79.6% and 97.4%, respectively and the specificity was 77.4%, 71.9% and 93.1%, respectively. The thresholds of HPI in the diagnosis of liver fibrosis at stage S1, stage S2, stage S3 and stage S4 were 0.291, 0.376, 0.503 and 0.590, respectively; the sensitivity was 95.7%, 93.8% and 94.4% and 97.4%, respectively and the specificity was 89.5%, 84.7%, 91.3% and 92.7%, respectively. Conclusions:The parameters of MR-PWI change regularly with the development of liver fibrosis in the cynomolgus monkey model, among which HPI is the best parameter for quantitative evaluation of the severity of liver fibrosis.

Objective To explore the methods and curative effect of metallic self-expanding stent in inoperable malignant gas-troduodenal obstruction. Methods The data of 15 cases with gastroduodenal obstruction including 9 cases of carcinoma of head of pancreas and 6 cases of carcinoma of stomach were analyzed retrospectively. The operative procedures of the stent implanted and the tors accepted more radiation dose because the manipulation was under the fluoroscopy in a short distance and with a full field of view. sions, the postoperative eating habit and the development turnover of disease. The main death reasons were tumor transfer and sys-tem exhaustion. Conclusion To pay close attention to the details and main points of operative procedure is the key point to implant stent successfully for malignant gastroduodenal obstruction. The determinative factor to influence the curative effect is the develop-ment turnover of tumor.

Objective To compare 18F-FDG、11C-MET and 11C-CHO PET/CT in rat C6 glioma and inflammation models and observe their correlations with HIF-1α and VEGF expressions.Methods Thirtytwo male Wistar rats were included to bear both C6 glioma and turpentine oil-induced acute inflammation (AI).18F-FDG,11C-MET and 11C-CHO PET/CT were performed on rats.The SUVmax ratios of tumor-tomuscle (T/M),AI-to-muscle (AI/M) and tumor selectivity index (SI) were calculated.One-way analysis of variance and two-sample t test were used for statistical analyses.HIF-1α and VEGF expression was detected by immunohistochemical staining.Spearman correlation analysis was performed to evaluate the relationship between T/M ratios and the expressions of HIF-1α or VEGF.Results T/M ratios of 18F-FDG,11 C-MET and 11C-CHO in C6 glioma were 6.89±2.53,2.75±0.87,2.73±1.01,and the AI/M were 4.77±2.21,1.75±0.66,2.23±0.90 respectively.The 18F-FDG and 11C-MET uptake between C6 glioma and AI were significantly different(tFDG =2.133,tMET =3.267,both P＜0.05).The SIMET was significantly higher than SIFDG(t =2.600,P＜0.05).The 11C-CHO uptake between tumor and inflammation showed no significant difference(t=1.537,P＞0.05).T/M ratios of 18F-FDG and 11C-MET were positively related to HIF-1α and VEGF expressions(rs =0.725,0.637,0.621,0.764,all P＜0.05).The T/M ratio of 11C-CHO related only to VEGF (rs =0.682,P＜0.05).Conclusions 18F-FDG and 11 C-MET PET/CT may differentiate C6 glioma from AI,and 11 C-MET PET/CT seems more tumor-selective.11C-CHO PET is less valuable for the differential diagnosis.The 18F-FDG and 11 C-MET uptake of C6 glioma may be related to tumor hypoxia.All the three tracers could reflect tumor angiogenesis,but with different sensitiveness.

Based on the capacitance coupling principle, we studied a capacitive way of non-contact electrocardiogram (EGG) monitoring, making it possible to obtain ECG on the condition that a patient is habilimented. Conductive fabric with a good electrical conductivity was used as electrodes. The electrodes fixed on a bed sheet is presented in this paper. A capacitance comes into being as long as the body gets close to the surface of electrode, sandwiching the cotton cushion, which acts as dielectric. The surface potential generated by heart is coupled to electrodes through the capacitance. After being processed, the signal is suitable for monitoring. The test results show that 93.5% of R wave could be detected for 9 volunteers and ECG with good signal quality could be acquired for 2 burnt patients. Non-contact ECG is harmless to skin, and it has advantages for those patients to whom stickup electrodes are not suitable. On the other hand, it is convenient to use and good for permanent monitoring.
Electric Conductivity ; Electrocardiography ; instrumentation ; Electrodes ; Humans

Objective To compare the 18F-FDG PET metabolic characteristics and VHRCT morphological characteristics between invasive and non-invasive adenocarcinoma presenting as pure ground-glass nodules(pGGN).Methods Fifty-one patients with pGGN from October 2010 to June 2016 were retrospectively enrolled in this study.There were totally 52 lesions with sizes of no more than 30 mm and were grouped depending on pathological and follow-up diagnosis (31 lesions in the invasive adenocarcinoma group and 21 lesions in the non-invasive group).Clinical and imaging features were analyzed including age,gender,lesion location,size,density,SUVmax T/N,spiculation,lobulation,pleural indentation,vascular connection signs,vacuole sign and the air bronchogram.T test or x2-test was used in the comparison of different manifestations between the two groups.Logistic regression analysis on clinical parameters was applied.The ROC curve was used to find the cutoff of T/N.Results In the invasive adenocarcinoma group,T/N,SUV density and size were 1.97±0.71,1.16±0.54,-(431±104)HU,(18.48±5.65)mm,respectively.In the non-invasive group,T/N,SUVmax density,size were 1.20±0.28,0.64±0.20,-(533± 109)HU,(12.05±5.04)mm,respectively.The differences of T/N,SUVmax density and size had statistical significance between the two groups (t=-5.40,-4.87,-3.39,-4.21,P＜0.05).Lobulation and vascular connection signs in the invasive adenocarcinoma group were found in 21 and 13 cases respectively,while in the non-invasive group,they were present in 2 and 1 case,respectively,which showed significant differences between the two groups(x2=17.85,7.01,P＜0.05).T/N,lobulation,and vascular connection signs were the independent factors for the differentiation of benign and malignant lesions.The ORs were 52.547,8.375,72.206,respectively.When T/N=l.62,the area under the ROC curve was 0.885.The sensitivity,specificity and accuracy were 77.42％,90.48％,82.69％,respectively.Conclusions Pulmonary pGGNwith T/N no less than 1.62,lobulation and vascular connection sign indicates an invasive adenocarcinoma.

OBJECTIVETo investigate the epidemiology, internal opening location, and risk factors associated with recurrence of anal fistula.

METHODSClinical data of 1783 hospitalized patients admitted for anal fistula treatment to Shanghai Shuguang Hospital from January 2013 to September 2015 were retrospectively analyzed. Fistula passing through anorectal ring or locating above was defined as high anal fistula (n=125). Internal opening location was defined as follows: posterior (5 to 7 o'clock), front(11 to 1 o'clock), left (2 to 4 o'clock) and right (8 to 10 o'clock).

RESULTSAmong 1783 cases, 1526 were male with a median age of 36 years, 257 were female with a median age of 35 years, and the ratio of male to female was 5.9 vs 1.0. In high anal fistula cases, this ratio of male to female was 7.3 vs 1.0. Posterior internal opening accounted for 51.4%(884/1720), while this percentage was 66.4%(83/125) in high anal fistula cases, which was significantly higher than 50.2%(801/1595) in low anal fistula cases(P=0.002). Postoperative recurrence rate was 2.6%(45/1720) and the rates in high anal fistula and low anal fistula were 13.6%(17/125) and 1.8%(28/1595) respectively, with significant difference(P=0.000). Multivariate logistic regression analysis showed that fistula height(OR=5.475, 95%CI:2.230 to 13.445, P=0.000), treatment history(OR=2.671, 95% CI:1.315 to 5.424, P=0.007), seton placement history (OR=4.707, 95%CI:1.675 to 13.232, P=0.003) and concomitant colitis(OR=10.300, 95%CI:1.187 to 89.412, P=0.034) were independent risk factors for anal fistula recurrence. Seton placement history was an independent risk factor for high anal fistula recurrence (OR=6.476, 95%CI:1.116 to 37.589, P=0.037).

CONCLUSIONSAnal fistula occurs in young and middle-aged male patient. Internal opening locates in posterior more commonly, especially in high anal fistula patients. Postoperative recurrence rate of high anal fistula is quite high. Patient with both high anal fistula and seton placement history has significantly high rate of postoperative recurrence.

Objective:To explore sagittal parameters change of upper cervical spine after anterior cervical decompression and fusion (ACDF) and analyze the influential factors by comparison between single-, double- and multi-level surgery.Methods:In this retrospective study, 126 patients (include 60 patients with radiculopathy, 41 patients with myelopathy and 25 patients with myeloradiculopathy) who underwent ACDF between December 2016 and December 2018, were followed up at least 1year ranged from14 to 38 months, with the average of 25.6±7.2 months. 20 patients were operated by single-level ACDF, 45 patients were operated by double-level ACDF and 61 patients were operated by 3- or 4-level ACDF. Standing radiographs of cervical spine and the flexion and extension cervical X-rays were obtained in all patients at 1week before, 3 months after and 1year after operation. The Japanese Orthopaedic Association (JOA) Scores, visual analogue scale (VAS) and neck disability index (NDI) were used to evaluate the clinical effectiveness. Cervical sagittal parameters were assessed with the following parameters: the platform angle of axis (C2Slope), the cobb angle and the range of motion (ROM) of C2-7, C0-1 and C1-2.Results:All the patients obtained satisfactory clinical effects. The mean operative time of single-, double- and multi-level group were 86.4±15.5 min, 117.6±15.6 min and 170.2±28.7 min, respectively. The intraoperative blood loss of 3 groups were 16.5±5.2 ml, 37.2±30.5 ml and 63.4±41.5 ml, respectively. There was statistically significant difference between the 3 groups ( P<0.05). In the single- and double-level groups, the changes of the cobb angle and ROM of upper cervical spine between 1 week before operation and 1 year after operation was no significant difference ( P>0.05). In the multi-level group, the ROM of atlantooccipital joint (C0-1) increased significantly from 11.5°±6.1° before operation to 16.1°±13.9° 3 months and 15.3°±4.8° 1 year after operation ( P<0.05). The cobb angle of upper cervical spine and C2Slpoe was decreased significantly from 21.0°±7.6°, 6.1°±6.7° before operation to 18.6°±7.7°, 4.3°±6.9° 3 months and 19.7°±7.2°, 5.6°±6.3° 1 year after operation respectively ( P<0.05). However, there was no significant difference of cobb angle ofatlantooccipital joint between 1 week before operation and 1 year after operation ( P>0.05). Conclusion:Single- and double-level surgery makes a better ability of preserving the restoration of cervical lordosis, with little impact on the upper cervical spine, meanwhile multi-level fusion shows a negative influence on the restoration and limits the range of motion, also increases risk of surgical operation and degeneration of the atlantooccipital joint, with the increased stress distribution and range of motion.

Objective To investigate the reference intervals of lipid metabolism indexes and dyslipidaemia situation among the a-dult of Tibetan in Ganzi County .Methods The serum samples were collected from 661 healthy subjects in Ganzi county ,total cho-lesterol(TC) ,triglyceride(TG) ,high density lipoprotein cholesterol(HDL-C) ,low density lipoprotein cholesterol(LDL-C) ,apoli-poprotein A1(ApoA1) and apolipoprotein B(ApoB) levels were measured .According to the American Society for Clinical Laborato-ry Standards(CLSI) C28-A3 documentation and the International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) guidelines for establishing of reference interval with reasonable method and reliable basis ,the interval value of this lipid metabolism indexes were calculated .The dyslipidemia situation was analyzed based on "The Guideline of Prevention and Treatment of Dyslipi-demia in Chinese Adults in 2007".Results In these population ,TG ,LDL-C and ApoB in the serum of male were higher than those of female ,while HDL-C and ApoA1 were lower than those of female ,the difference was statistically significant (P<0 .05) .TC , LDL-C and TG level had a change tendency with ages obviously ,while the changes of HDL-C ,ApoA1 and ApoB metabolism level were not inconspicuous .In this population ,TC ,LDL and ApoB reference intervals were 2 .75 -6 .82 mmol/L ,1 .36 -4 .3 mmol/L and 0 .24-1 .38 mmol/L respectively .The reference interval of TG ,LDL-C and ApoA1 in male population were 0 .5-2 .36 mmol/L ,0 .9-1 .93 mmol/L and 0 .82-1 .87 mmol/L respectively ,meanwhile ,the reference range of TG ,HDL-C and ApoA1 in female population were 0 .47-3 .19 mmol/L ,0 .96-2 .19 mmol/L and 0 .94-2 .02 mmol/L respectively .The incidence of dyslipidemia in Tibetan adults was high ,the incidence of hypercholesterolemia ,hypertriglyceridemia ,mixed hyperlipidemia and low high-density lip-oprotein were 32 .07% ,21 .18% ,12 .86% and 6 .51% respectively .Conclusion In this research ,we established the reference inter-val of blood lipid metabolism indexes of Tibetan adults in Ganzi county and analyzed the incidence of hyperlipidemia in this popula-tion initially .This results provide reference data for clinical intervention treatment of patients with hyperlipidemia in Tibetan popu-lation in Ganzi area ,which is helpful for guiding the prevention and treatment of dyslipidemia in this region .