Endoscopic ultrasonography (EUS)is routinely performed before endoscopic submucosal dissection (ESD)for treatment of upper gastrointestinal stromal tumors.However,when a miniprobe sonography (12,15 and 20 MHz)was used,the size of tumor revealed by EUS was often inconsistent with what it actually was,which might increase the difficulty of ESD and the risk of perforation and massive bleeding.Aims:To investigate the value of standard probe (5 and 7.5 MHz)EUS in detecting the size of upper gastrointestinal stromal tumors before ESD.Methods:Clinical data of patients who were suspicious of esophageal and gastric stromal tumors by gastroscopy and EUS from Jan.2012 to Oct.2014 at the Renmin Hospital of Wuhan University were collected.Of them,195 cases treated by ESD were retrospectively analyzed.Results:Of 195 cases treated by ESD,37 cases diagnosed by standard probe EUS and 108 cases diagnosed by miniprobe EUS were confirmed as stromal tumors by pathology.Fourteen cases were failure for ESD and then transferred to surgical treatment,one was due to misjudgement of the origin of tumor by standard probe EUS and 9 were due to misjudgement of the size of tumor by miniprobe EUS.The misjudgement rate of standard probe EUS was lower than that of miniprobe EUS with an insignificant difference (2.7%vs.8.3%,P>0.05).In 9 cases misjudged by miniprobe EUS, the size of tumor presented by miniprobe EUS was significantly smaller than its real size [(1.22 ±0.51)cm vs.(3.97 ±1.06)cm,P<0.01].ESD was avoided or terminated in 3 cases because of the accurate estimation of tumor origin, structure and blood flow by standard probe EUS.Conclusions:For patients who are going to receive ESD for suspected upper gastrointestinal stromal tumors,it would be best to select standard probe EUS to detect the size,origin and blood flow of the tumor before ESD.It will decrease the risk and improve the success rate of ESD.

Objective:To explore the effect of flipped classroom combined with scenario simulation in the teaching reform on four basic medical puncture techniques of clinical skills training.Methods:A total of 1 275 students majoring in five-year clinical medicine in Guangzhou Medical University were enrolled in the study. The control group (647 cases from Batch 2015) were given the traditional teaching pattern and the experimental group (628 cases from Batch 2016) adopted flipped classroom combined with scenario simulation. At the end of the course, the performance in the tests of four basic medical puncture techniques in the objective structured clinical examination (OSCE) of the two groups were compared. The feedback and evaluation of this teaching mode in the experimental group were investigated by questionnaires. SPSS 19.0 was used for independent samples t test. Results:All the scores of the tests of four basic medical puncture techniques in the experimental group were significantly higher than those in the control group: abdominocentesis [(87.89±7.13) vs. (82.60±10.74) points], thoracocentesis [(85.20±7.39) vs. (81.96±7.76) points], bone marrow aspiration [(88.13±6.00) vs. (83.50±9.63) points], and lumbar puncture [(91.91±7.19) vs. (80.74±12.20) points], with significant differences ( P<0.001). The results about the feedback and evaluation in the experimental group showed that the students gave an average score of 8.4 points to their satisfaction with the new teaching mode. The approval rates of the teaching effect evaluation items such as teaching arrangement, improving learning ability, improving clinical practice ability and school promotion were higher than 90.0%. Conclusion:Flipped classroom combined with scenario simulation, which is worthy to be popularized, can not only improve the students' performance in the tests of four basic medical puncture techniques in the OCSE, but also improve teaching satisfaction and teaching effect.

Objective:To evaluate the performance of three antibody kits for novel coronavirus (SARS-CoV-2) and to investigate the feasibility and advantages of them in clinical application.Methods:A total of 104 patients who were admitted to Guangzhou Eighth People′s Hospital with COVID-19 from January to February 2020 were selected as research group. Fifty-one healthy subjects were selected during the same period as negative control group. Serum antibodies (IgM/IgG) against SARS-CoV-2 were detected using two kinds of colloidal gold kits (A and B kits) and one chemiluminescence kit (C kit). The positive rates of SARS-CoV-2 nucleic acid in different samples from patients with COVID-19 were retrospectively analyzed.Results:The clinical sensitivity of A kit to detect SARS-CoV-2-specific IgM and IgG was 77.88% (81/104) and 65.38% (68/104), respectively, and the clinical specificity was 70.59% (36/51) and 100.00% (51/51). However, the false positive rate in IgM detection was as high as 29.41% (15/51). The sensitivity of B kit to test total antibodies to SARS-CoV-2 was 63.46% (66/104), and the clinical specificity was 94.12% (48/51). The clinical sensitivity of C kit to detect SARS-CoV-2-specific IgM and IgG were respectively 31.73% (33/104) and 64.42% (67/104), and the clinical specificity were both 98.04% (50/51). There was a moderate correlation between the detection results of two colloidal gold kits and the chemiluminescence kit with the Kappa values of 0.462 and 0.587 ( Z=6.157, P<0.01; Z=7.345, P<0.01). C kit had the highest positive detection rate for IgG, and would be more reliable to be used for IgG detection in COVID-19 patients 14 d after onset. The total positive detection rate of nucleic acid in all types of samples was 63.46% (66/104). The highest positive detection rate was in throat swabs or sputum samples, followed by those in blood samples and anal swabs. No viral nucleic acid was detected in urine samples for the time being. Conclusions:SARS-CoV-2-specific antibodies could be detected in the early or late stage of COVID-19. The method of antibody detection has the advantages of shorter detection time, simple operation and high biological safety, indicating that it could be used as a supplementary or auxiliary detection for the diagnosis of suspected COVID-19 cases with negative nucleic acid test results. The chemiluminescence kit has good sensitivity and specificity, and is well recommended for clinical laboratories.

Objective: To explore the Expressions of multiple inflammation markers in the patients with 2019 novel coronavirus pneumonia (COVID-19) and their clinical values, and to provide theoretical basis for clinical diagnosis and treatment. Methods: A total of 164 patients, diagnosed with COVID-19 and admitted to Guangzhou Eighth People's Hospital from January to February 2020, were selected as the research group and divided into three groups (ordinary, severe, and critically severe pneumonia) according to the disease severity. Meandwhile 66 non-infected patients during the same period were selected as negative control group. The expressions of WBC, LYM, CRP, SAA, and PCT were retrospective studied and compared between groups. The diagnostic values of WBC, CRP, SAA and the combination of these three markers in all patients with COVID-19 and in different severity groups were analyzed by ROC curve. Results: Compared with control group (WBC count :8.13(6.51,9.42)×10⁹/L, LYM count:2.00(1.28,2.43)×10⁹/L), WBC count [4.94(4.05, 6.67) ×10⁹/L] and LYM count [1.33(0.94, 1.96) ×10⁹/L] of COVID-19 patients were significantly reduced (Z=-7.435, P<0.01; Z=-4.906, P<0.01) . Compared with the control group [CRP: 1.36 (0.57~5.67) mg/ml; SAA:[4.98 (4.80~15.75) mg/mL], CRP [7.93 (2.45~23.98) mg/ml] and SAA [34.13 (4.83~198.40) mg/ml] were increased in research group (Z=-5.72, P<0.01; Z=-4.166, P<0.01) . PCT in the control group and the research group were 0.100 0(0.030 6~0.100 0)ng/ml and 0.044 5(0.031 6~0.077 0)ng/ml, respectively. There was no statistical difference between two groups (Z=-1.451, P=0.147) . The areas under the ROC curve (AUC) of WBC, CRP and SAA in patients with COVID-19 were 0.814, 0.742, 0.673, respectively (P<0.01), while the AUC of the combination of three indexes for COVID-19 diagnosis was 0.882, with 83.33%(55/66) specificity and 84.76% (139/164) sensitivity, P<0.01.The AUCs of WBC, CRP, and SAA for predicting severe and critically severe COVID-19 were 0.799, 0.779, and 0.886 , respectively (P<0.01), and the AUC of the combination of three indexes for the diagnosis of severe and critically severe COVID-19 was 0.924, with 78.67% (118/150) specificity and 14/14 sensitivity (P<0.01). Conclusion Combining detection of WBC, CRP and SAA can improve the specificity and sensitivity of COVID-19 diagnosis, with a high diagnostic value for severe and critically severe COVID-19.