Objective To explore the identification of the hypoxia regions within the primary foci and imaging time selection in 18F-fluoromisonidazole (FMISO) imaging on patients with nasopharyngeal carcinoma (NPC).Methods From July 2013 to July 2014,44 NPC patients (33 males,11 females,age range:18-74(53.45± 12.88) years) underwent 18 F-FMISO PET/CT imaging,including 3 cases with twice imaging (totally 47 case times).Inaging data were acquired and reconstructed 2 and 4 h after the injection of 18 F-FMISO.1s F-FMISO PET/CT images were merged with MRI images obtained 1 week before to construct fusion images.The boundary of primary tumor was determined based on MRI.Visual analysis was performed and SUVmax of posterior cervical muscles,NPC primary foci was measured by 2 observers respectively.The uptake ratio of primary tumor to muscle (TMR) was calculated.The identify consistency of hypoxic region between two observers were evaluated by Kappa test and intraclass correlation coefficient (ICC).The image contrast was evaluated by Wilcoxon paired rank sum test of TMR.Results PET images and MRI images of NPC primary foci were successfully fused.Positive non-NPC tissues were identified by MRI.The visual recognition of hypoxic regions of the two observers for 2 and 4 h imaging were highly consistent (Kappa =0.931 and 0.965,both P＜0.001).There was a high degree of consistency between the SUVmax of posterior cervicalmuscles and that of primary tumors.ICCs of posterior cervical muscles in 2 and 4 h were 0.896 (95％ CI:0.814-0.942) and 0.924 (95％ CI:0.865-0.958),respectively.ICCs of primary tumors in 2 and 4 h were 0.991 (95％ CI:0.985-0.995) and 0.998 (95％ CI:0.996-0.999),respectively.TMRs (M(P25,P75))in 2 and 4 h were 1.560 (1.341,3.015) and 1.675 (1.387,3.001) respectively in 24 positive case times,and the difference was statistically significant (z=-2.557,P＜0.05).Conclusions Using fusion images of 18F-FMISO PET and MRI,hypoxic tissues within NPC primary foci can be accurately identified.There is a high degree of consistency within the visual and quantitative analysis of two observers.The image contrast of 18F-FMISO PET at 4 h is superior to that at 2 h.

Objective To understand the malaria epidemic situation in Chengdu City,so as to provide the evidence for effec-tively carrying out the malaria elimination work. Methods The data of imported malaria in Chengdu City from 2012 to 2016 were collected from the Disease Surveillance Information Reporting System of Chinese Center for Disease Control and Prevention and analyzed respectively. Results A total of 240 imported malaria cases were reported in Chengdu City from 2012 to 2016. In de-tail,68.75％of the cases were falciparum malaria cases,20.41％were vivax malaria cases,2.50％were quartan malaria cases, 6.25％were ovale malaria cases,and 2.08％were mixed Plasmodium infections. Among them three patients died,with a mortali-ty of 1.25％. All of the cases were infected overseas,among which 224 patients returned from Africa and 16 patients from South-east Asia. The annual average morbidity was 0.28/100000,and there was a significantly difference among annual average mor-bidities(χ2=23.87,P<0.001). There were malaria cases reported in every month,and no significantly difference among sea-sons(χ2=0.833,P>0.05). Conclusion The number of overseas imported malaria in Chengdu City increases year by year. The effective measures to control the overseas imported malaria should be strengthened to consolidate the achievements of malar-ia elimination.

This article introduced the conception and the harm of external ventricular drainage (EVD) catheter related infections. Risk factors of external ventricular drainage catheter related infections were focused. The six aspects were reviewed: the type of EVD catheters, the duration of EVD retention, the frequency of cerebrospinal fluid sampling during the retention, the frequency of VED catheter replacements, the location of EVD implantation, and the maintenance operation of EVD catheters. The article provided data support for the clinical decision-making of medical staff.

Objective To explore the relationship between the maximum standardized uptake value ( SUVmax ) of 18 F-fluoromisonidazole ( FMISO) PET/CT and the pathological classification, differentiation, T stage and primary tumor volume of nasopharyngeal carcinoma ( NPC) . Methods A retrospective analysis was performed on 41 patients with NPC (31 males, age 18-74 years;10 females, age 35-67 years) who underwent head and neck 18 F-FMISO PET/CT from 2012 to 2015. The relationship between the clinicopath-ological parameters (pathological classification, differentiation, T stage, tumor volume) of primary lesion and SUVmax were analyzed. Mann-Whitney u test, approximate t test and Spearman correlation were used for data analysis. Results There was no significant difference in SUVmax between non-keratinizing carcinoma and squamous cell carcinoma ( u=183.5, P>0.05) , nor between the differentiated carcinoma and undiffer-entiated carcinoma( t'=-1.23, P>0.05) . SUVmax of T1-T2 primary tumor was significantly lower than that of T3-T4 tumor (1.52±0.43 vs 2.05±0.85; t'=-2.60, P<0.05), and SUVmax was correlated with primary tumor volume ( rs=0.488, P<0.05) . Conclusions The hypoxic degree is related with T stage and primary tumor volume in NPC. The combination analysis of T stage and tumor size will contribute to the assessment of oxygen level and prognosis of primary NPC.

Objective:To analyze the feasibility of developing clinical pediatrics curriculum for pediatric students at the pre-clinical stage, and to provide a basis for the subsequent curriculum construction.Methods:A total of 90 pediatric medical students were enrolled, including pre-clinical group (G1, third semester of the second year, n=47) and the clinical clerkship group (G2, seventh semester of the fourth year, n=43). A questionnaire survey was conducted to compare the two groups from three aspects: clinical interest, learning methods and learning ability. And 24 and 20 students were randomly selected from the two groups to participate a clinical course respectively. Both of the formative evaluation and in-class test were carried out to compare the learning performance and learning effect between G1 and G2. SPSS 22.0 was used for data analysis. The counting data were described by case number and rate, and the frequency between groups was compared by chi-square test. When the chi-square test condition is not met, Fisher's exact test was performed. Normal distribution test was carried out for measurement data. Two independent sample t test was conducted for the comparison between groups of normal distribution data and Mann-Whitney U test for the comparison between groups of skewed distribution respectively. Results:There was no significant difference in clinical interest and pre-clinical interest between the two groups (Fisher's exact probability method, P=0.252, 1.000). There were partial differences in learning methods: G1 spent more time learning after class ( Z=-2.36, P=0.018), learned more in spare time ( Z=2.53, P=0.011), learned more on the homework ( P=0.020), and had a higher preview rate ( Z=-5.07, P < 0.001). There were also partial differences in learning ability: G2 had better literature retrieval ability ( χ2=10.57, P=0.001); G2 had higher scores on class and extended class performance ( t=-3.18, P=0.004; t=-10.14, P<0.001). In terms of learning effect, G2 scored higher scores on only one multiple choice question ( t=-2.46, P=0.022). Conclusion:The pediatrics students at the pre-clinical stage have certain interest and ability to receive clinical pediatrics courses. Sufficient pre-class preparation and appropriate curriculum design are helpful to the early cultivation of student's clinical thinking.

Objective:To study the correlation between the copy number variations of CCND1 gene and chromosome 11 and their associations with clinicopathologic features in acral melanoma.Methods:Thirty-three acral melanoma cases diagnosed at the Department of Pathology of Peking University Third Hospital, Beijing, China from January 2018 to August 2021 were collected. Fluorescence in situ hybridization (FISH) was used to detect the copy number of CCND1 gene and centromere of chromosome 11. The relationship between the copy numbers of CCND1 and chromosome 11 centromere, and the correlation between CCND1 copy number and clinicopathologic characteristics were analyzed.Results:There were 15 male and 18 female patients, with an age ranging from 22-86 years. 63.6% (21/33) of the patients had an increased CCND1 gene copy number. 21.2% (7/33) of patients with increased CCND1 copy number had an accompanying chromosome 11 centromere copy number increase. 27.3% (9/33) of the cases had a low copy number of CCND1 gene, and 4 of them (4/33, 12.1%) were accompanied by chromosome 11 centromere copy number increase. 36.4% (12/33) of the cases had a high copy number of CCND1 gene, and 3 (3/33, 9.1%) of them were accompanied by chromosome 11 centromere copy number increase. No cases with CCND1 low copy number increase showed CCND1/CEP11 ratio greater than 2.00. The 11 cases with CCND1 high copy number increase showed CCND1/CEP11 ratio greater than or equal to 2.00. However, there was no significant correlation between CCND1 copy number increase and any of the examined clinicopathologic features such as age, sex, histological type, Breslow thickness, ulcer and Clark level.Conclusions:CCND1 copy number increase is a significant molecular alteration in acral melanoma. In some cases, CCND1 copy number increase may be accompanied by the copy number increase of chromosome 11. For these cases the copy number increase in CCND1 gene may be a result of the copy number change of chromosome 11.

Objective To explore the risk factors of catheter-related infections of external ventricular drainage (EVD),so as to provide evidence for effective prevention and control measures.Methods A total of 428 patients′ clinical data were collected by retrospective case analysis in cluster sampling,who underwent external ventricular drainage in Neurosurgery Department of a class Ⅲ grade A hospital in Shanghai from January 2014 to October 2016. The incidence of EVD infection was analyzed. At the same time,univariate analysis and multivariate Logistic regression analysis were adopted for risk factors of EVD related infection.Results The catheter-related ventricular infections occurred in 36 of 428 cases of patients,with the incidence rate 8.41％. The detection rate of pathogens in cerebrospinal fluid was 75.00％,and Gram-negative bacteria were the main pathogens (78.13％),among which the most common was Acinetobacter baumannii (28.11％). Univariate analysis showed that the incidence of catheter-related ventricular infection was related to gender,age,admission diagnosis,diabetes mellitus,preoperative pulmonary infection,Glasgow Coma Scale (GCS) score,American Society of Anesthesiologists (ASA) physical status classification,duration of EVD,type of EVD,number of catheters,frequency of replacing catheter,frequency of sampling cerebrospinal fluid (P<0.05). Multivariate Logistic regression suggested that duration of EVD,number of catheters,pulmonary infection and frequency of sampling cerebrospinal fluid were independent risk factors causing catheter-related ventricular infection (OR=1.070,13.236,6.800,6.248).Conclusions The catheter-related ventricular infection can be caused by single factor or the synergistic action of multiple factors. The control of pulmonary infection and the management of blood glucose level are helpful to reduce the infection of EVD related infection.

Objective: This study aimed to assess the association between hypertension and carotid plaque in a research population in China. Methods: The subjects of this study were selected from a population undergoing physical examination at the Fourth Medical Center of PLA General Hospital in 2017. We collected information on physical examination, physiological index test, blood pressure indicators were analyzed according as continuous variables (systolic blood pressure, diastolic blood pressure, and pulse pressure) and categorical variables (hypertension and quartile of blood pressure pulse pressure). A multivariate logistic regression model was conducted to estimate the correlation between blood pressure and carotid plaque development. Results: A total of 716 individuals were surveyed, including 321 men (44.8%) and 395 women (55.2%), and the prevalence of hypertension and carotid plaque were 40.9%(293 cases) and 40.4% (289 cases), respectively. The prevalence of carotid plaque was higher in individuals aged ≥60 years, diabetes mellitus, hypertension and increased waist circumference, systolic blood pressure, fasting blood glucose and glycosylated hemoglobin. The prevalence of carotid plaque increased with the increase of the quartile of blood pressure and pulse pressure (P_trend<0.05). After adjustment for age, sex, BMI, waist circumference, and total cholesterol, triglyceride, fasting blood glucose, glycosylated hemoglobin, and hemoglobin levels, every 1 mmHg increased systolic blood pressure increases the risk of carotid plaque by 1.4% (95%CI: 1.005-1.024). Compared with the control group, the risk of carotid plaque increased by 86.8% (95%CI: 1.175-2.946) and 84.8% (95%CI: 1.098-3.110) and 119.6% (95%CI: 1.165-4.142) in the group of normal high blood pressure, grade 1 hypertension and grade 2 and grade 3 hypertension, respectively; compared with the control group, the risk of carotid plaque increased by 56.2% in the group of pulse pressure difference≥60 mmHg (95%CI: 1.049-2.326), in which the risk of carotid plaque increased by 73.3% (95%CI: 1.007-2.983) in women with pulse pressure difference≥60 mmHg (1 mmHg=0.133 kPa); in the control group with pulse pressure difference of four categories Q1 (<42 mmHg), the risk of carotid plaque increased by 92.2% (95%CI: 1.173-3.149) and 95.0% (95%CI: 1.147-3.316) in Q3 (50-61 mmHg) and Q4 (≥62 mmHg), respectively. Conclusion Increased blood pressure or pulse pressure are associated with increased prevalence of carotid plaque. Prevention of elevated blood pressure and pulse pressure might be one of the effective precautions for the prevention of carotid plaque development.