Objective To com pare and explore the application value of diatom nitric acid digestion method and plankton 16S rDNA PCR method for drow ning identification. Methods Forty drow ning cases from 2010 to 2011 were collected from Department of Forensic Medicine of Wenzhou Medical University. Sam ples including lung, kidney, liver and field water fromeach case were tested with diatom nitric acid digestion method and plankton 16S rDNAPCR method, respectively. The Diatom nitric acid digestion method and plankton 16S rDNAPCR method required 20 gand 2g of each organ,and 15 mL and 1.5 mL of field water, respectively. The inspection time and detection rate were com pared between the two methods. Results Diatom nitric acid digestion method m ainly detected two species of diatom s, Centriae and Pennatae, while plankton 16S rDNA PCR method am plified a length of 162 bp band. The average inspection time of each case of the Diatom nitric acid digestion method was (95.30±2.78) min less than (325.33±14.18)min of plankton 16S rDNA PCR method (P<0.05).The detection rates of two methods for field water and lung were both 100% . For liver and kidney, the detection rate of plankton 16S rDNA PCR method was both 80% , higher than 40% and 30% of diatom nitric acid digestion method (P<0.05), respectively. Conclusion The laboratory testing method needs to be appropriately selected according to the specific circum stances in the forensic appraisal of drow ning. Com pared with diatom nitric acid digestion method, plankton 16S rDNA PCR method has practice values with such advantages as less quantity of sam ples, huge inform ation and high specificity.

The early involvement of specialty,case and scientific research were applied to forensic medicine teaching and has achieved significant effect.

Basic knowledge of forensic science is theoretical and abstract,therefore,confir-matory experiment teaching is often adopted in the experiment teaching. International education has become an important topic in medical colleges and universities. Forensic medicine is a compulsory subject for medical international students. This article discussed the exploration and practice in teach-ing forensic medicine for international students at Wenzhou Medical University,which included faculty constructing and training,encouraging whole English teaching by young teachers,applying heuristic interactive teaching and case teaching,establishing strict attendance and appraisal system and con-ducting comprehensive evaluation on medical teaching quality and teaching management.

Protective effect and mechanism of electroacupuncture (EA) on acute reperfusion ventricular arrhthmia was investigated. Ventricular arrhythmia was induced by occlusion of the proximal left anterior descend (LAD) branch of coronary artery for 5 min and followed with 15 min reperfusion. EA on acupoint "Neiguan", "Jianshi" was performed at 30 min before ligation and continued another 5 min during ischemia. Isoprenaline (20, 30 and 50 microg/kg) or atropine (1 mg/ kg) was intravenously injected at 5 min before ischemia. The results showed that EA significantly decreased the incidence of ischemia/reperfusion (I/R) induced ventricular tachycardia (VT), ventricular fibrillation (VF) and mortality as compared to I/R group. Atropine partially suppressed the EA's effect of antiarrhythmia; Isoprenaline increased the incidence and severity of reperfusion arrhythmia, which was inhibited by EA, but this inhibition of EA was blocked with increasing dose of isoprenaline. The results indicated that EA treatment could prevent the occurrence of reperfusion ventricular arrhythmia in rats with myocardial ischemia, and its mechanism might be related to the regulation of EA on the beta-adrenoceptors and M-cholinergic receptor activation in myocardium.

The medical assistance to advanced schistosomiasis patients established by the Chinese government is a major public facility for patients with advanced schistosomiasis. Since the medical assistance to advance schistosomiasis patients in Hu?nan Province started ten years ago,a set of mature and operable programs with whole program management and related technolo?gies has been developed. The author investigated the data on medical assistance to advanced schistosomiasis patients in Hunan Province during the last 10 years(from 2006 to 2015)retrospectively,and found that the program had high therapeutic effect and high satisfaction degree of both patients and the society. In order to improve the management of the medical assistance to ad?vanced schistosomiasis patients and share our experiences of the whole program management and related technologies with the colleagues of other provinces,this paper mainly illustrates the experiences of the program,as well as the existing problems and related strategies.

Protective effect and mechanism of electroacupuncture (EA) on acute reperfusion ventricular arrhthmia was investigated. Ventricular arrhythmia was induced by occlusion of the proximal left anterior descend (LAD) branch of coronary artery for 5 min and followed with 15 min reperfusion . EA on acupoint "Neiguan", "Jianshi" was performed at 30 min before ligation and continued another 5 min during ischemia. Isoprenaline (20, 30 and 50 μg/kg) or atropine (1 mg/kg) was intravenously injected at 5min before ischemia. The results showed that EA significantly decreased the incidence of ischemia/reperfusion (I/R) induced ventricular tachycardia (VT), ventricular fibrillation (VF) and mortality as compared to I/R group. Atropine partially suppressed the EA's effect of antiarrhythmia; Isoprenaline increased the incidence and severity of reperfusion arrhythmia, which was inhibited by EA, but this inhibition of EA was blocked with increasing dose of isoprenaline. The results indicated that EA treatment could prevent the occurrence of reperfusion ventricular arrhythmia in rats with myocardial ischemia, and its mechanism might be related to the regulation of EA on the β-adrenoceptors and M-cholinergic receptor activation in myocardium.

Objective:To investigate the clinical value of virtual monoenergetic images (VMI) and electron density map (EDM) derived from the dual-layer spectral detector CT (DLCT) in the differential diagnosis of benign and malignant pulmonary ground glass nodules (GGN).Methods:From July 2019 to August 2020, a total of 65 patients with lung GGN (27 benign GGNs and 38 malignant GGNs) confirmed by pathology were retrospectively enrolled in Gulou Clinical Medical College of Nanjing Medical University. All the patients underwent DLCT plain scanning within two weeks before the surgery. The conventional 120 kVp polyenergetic image (PI), EDM and 40-80 keV VMI were reconstructed. The differences of CT and electron density (ED) values between benign and malignant lesions on different images were compared by Mann-Whitney U test. Independent t-test was used to compare the lesion size and χ 2 test was used to analyze the CT features (including lesion location, shape, edge, internal structure, adjacent structure, nodule type) between benign and malignant lesions. Receiver operating characteristic (ROC) curve was used to analyze the efficacy of different energy spectrum quantitative parameters in the differential diagnosis of benign and malignant GGN. The statistically significant CT signs and energy spectrum quantitative parameters were analyzed by logistic regression analysis to find out the independent risk factors of malignant GGN, and then ROC curve analysis was performed for each independent risk factor alone or in combination. Results:There were significant differences in lesion shape, spiculation, lobulation, location and size between benign and malignant groups ( P<0.05). The CT value of pulmonary GGN in PI, 40-80 keV VMI and the ED value in EDM were statistically different between benign and malignant lesions ( P<0.05). The area under ROC curve (AUC) were 0.680, 0.682, 0.683, 0.686, 0.694, 0.676 and 0.722, respectively, among which the ED value had the highest AUC. Binary logistic regression analysis was carried out with GGN shape, spiculation, lobulation, location, size, ED value and CT value in PI, 40-80 keV VMI as independent variables, and malignant GGN as dependent variables. The results showed that ED value (OR=1.045, 95%CI 1.001-1.090, P=0.044), lesion size (OR=1.582, 95%CI 1.159-2.158, P=0.004), spiculation sign (OR=11.352, 95%CI 2.379-54.172, P=0.002) were independent risk factors for malignant GGN. ROC curve analysis showed the AUC of ED value, lesion size, spiculation sign and combination of the three for differential diagnosis of benign and malignant GGN were 0.722, 0.772, 0.698 and 0.885. The AUC for the combined parameters was the largest, with sensitivity of 92.1% and specificity of 74.1%. Conclusion:The diagnostic efficacy of EDM is higher than that of other VMI in the differential diagnosis of pulmonary GGN by DLCT images; The efficacy is further improved when EDM is combined with lesion size and spiculation sign for comprehensive diagnosis.

Objective:To explore the value of dual-layer spectral detector CT in differentiating the diagnosis of lung cancer and inflammatory nodules.Methods:A total of 92 patients undergoing enhanced chest scan from March 2019 to September 2020 at Renji Hospital, School of Medicine, Shanghai Jiaotong University, were retrospectively enrolled in the study. The conventional CT parameters, spectral CT parameters were measured and the nodules′ morphological characteristics were analyzed. Later the factors with statistical significance were identified as independent variables in a logistic regression model to establish models for predicting malignant nodules. ROC curve was used to assess the diagnostic performance for the conventional CT model, spectral CT parameters and combined model, respectively. Differences in the area under the ROC curve (AUC) were analyzed by the DeLong test.Results:Lobulated sign (42 and 8, respectively, χ2=10.779, P=0.001), short burr sign (41 and 7, respectively, χ2=11.911, P=0.001), pleural indentation sign (45 and 9 respectively, χ2=11.705, P=0.001), vascular convergence sign (35 and 8, respectively, χ2=5.337, P=0.021) and the venous phase iodine concentrations (IC) value [(2.1±0.5) mg/ml, (2.3±0.5) mg/ml, t=-2.464, P=0.016], normalized iodine concentrations (NIC) value (0.40±0.06, 0.45±0.08, t=-6.943, P<0.001), and Z-effective (Z eff) values (8.38±0.21, 8.49±0.19, t=-2.122, P=0.037) were significantly different between the lung cancer group and the inflammatory group, while other CT signs and CT indicators were not significantly different between the lung cancer group and the inflammatory group ( P>0.05). The conventional CT model was established with lobulated sign, short burr sign, pleural indentation sign, vascular convergence sign, and the AUC for differential diagnosis of lung cancer and inflammatory nodules was 0.827. The spectral CT parameter model was established with venous phase IC, venous phase NIC, and venous phase Z eff value, and the AUC for differential diagnosis of lung cancer and inflammatory nodules was 0.899. The conventional CT model combined spectral CT parameter model was established with the significant factors in the univariate analysis, and the AUC for differential diagnosis of lung cancer and inflammatory nodules was 0.925. The AUC of the combined model showed no significant difference from that of the spectral CT parameter model ( Z=1.794, P=0.073). However, AUC of the combined model was significantly higher than that of evaluation based on conventional CT alone ( Z=2.156, P=0.031). Conclusion:Spectral CT parameters combined with conventional CT signs can improve the differential diagnosis efficiency between lung cancer and inflammatory nodules.

Objective:To investigate the clinical value of iodine density map and low keV virtual monoenergetic images (VMI) derived from dual-layer spectral detector CT (DLCT) for the pancreatic neuroendocrine tumors (pNETs) detection.Methods:From January to June 2019, data of 23 pathologically confirmed patients of pNETs were retrospectively analyzed. All of the patients underwent pancreas enhanced DLCT scanning within 1 week before surgery. The conventional polyenergetic images (PI), iodine density map and 40, 50, 60, 70 keV VMI were generated. One resident radiologist with 3 years’ experience and one senior radiologist with over 10 years’ experience interpreted the images for the lesion detection independently using the following image series: PI, VMI (40-70 keV), PI combined with iodine density map. Lesion detection rates were recorded and compared among different image series. The CT value and noise of lesion, normal pancreatic parenchyma, and abdominal subcutaneous fat were measured in PI and VMI in both arterial and portal vein phases. The contrast-to-noise ratio (CNR) of lesion was calculated. The CT value of lesion and normal pancreatic parenchyma, CNR of lesion, and image noise were compared using repeated one-way ANOVA test. Subjective image quality was assessed with a 5-point scale and compared with Friedman test.Results:A total of 26 lesions were confirmed from 23 patients. For resident radiologist and senior radiologist, the detection rates of pNETs lesion using PI were 76.9% (20/26) and 84.6% (22/26) respectively, and both improved to 92.3% (24/26) using image series of 40 and 50 keV VMI. For senior radiologist, the pNETs lesion detection rate was further improved to 96.2% (25/26) using image series of PI with iodine map. The CT value of lesion and normal pancreatic parenchyma, CNR, and image noise had statistical differences among PI and VMI (40-70 keV) in both arterial and portal vein phase ( P<0.001). The mean CT attenuation and CNR of lesion in VMI increased significantly as the energy level decreased.The CNR of lesion in all VMI (40-70 keV) was significantly higher than that in PI. The median of subjective scores of image quality in PI and VMI (40-70 keV) were 3, 3, 4, 4, and 5 respectively, and the difference was statistically significant (χ2=66.393, P<0.001). Conclusions:The low keV VMI derived from DLCT can increase the CT value and CNR of pNETs, and the lesion detection rate can be improved combined with iodine density map. The CNR of pNETs is the highest in 40 keV VMI, and image noise is still lower than that of PI, so 40 keV VMI is recommended for clinical application.

Objective:To investigate the clinical value of multiparametric myocardial imaging using a dual-layer detector spectral CT in the non-invasive preoperative assessment of patients with coronary atherosclerotic heart disease (CHD) undergoing percutaneous coronary intervention (PCI).Methods:The clinical and imaging data of 90 patients who underwent coronary CT angiography (CCTA) with dual-layer spectral detector CT and invasive coronary angiography (ICA) within 30 days at the Affiliated Changshu Hospital of Nantong University from January 2021 to October 2022 were retrospectively analyzed. A total of 189 coronary arteries were included in the study cohort. The patients were divided into PCI ( n=44) and non-PCI groups ( n=46) according to whether they received PCI after evaluation with ICA. The diameter stenosis rate of the coronary arteries, myocardial iodine concentration (IC) and effective atomic number (Z eff) values were obtained from CCTA conventional and spectral images. The IC values and Z eff values of the myocardium in the areas with abnormal perfusion were compared with those in the areas with normal perfusion. The diagnostic performance of these parameters, as well as their combined model, was evaluated and compared using receiver operating characteristic (ROC) curve and area under the curve (AUC) in the pre-PCI assessment of patients with CHD. Results:Baseline patient data did not show statistically significant differences between the PCI and non-PCI groups (all P>0.05). There were statistically significant differences in IC values [(0.42±0.28) and (2.26±0.48) mg/ml] and Z eff values (7.39±0.33 and 8.50±0.25) between the myocardium areas with abnormal perfusion and the myocardium areas with normal perfusion in all patients (all P<0.001). The AUC for assessing whether patients with CHD need PCI treatment using myocardial IC and Z eff values were 0.865 and 0.853, respectively, which were significantly higher than assessment based only on lumen diameter stenosis rate (AUC=0.726, P<0.001). Conclusions:The IC and Z eff derived from myocardial spectral images can be used to diagnose myocardial perfusion abnormalities in patients with CHD. The spectral myocardial multi-parameters imaging shows promising potentials in pre-PCI assessment of patients with CHD, which can improve the efficiency of evaluation and may help to avoid unnecessarily invasive procedures.