BACKGROUND: The normal clinical index and the standard error of ultrasonic bone density in the population of normalchildren aged 6-12 years have not yet been established. OBJECTIVE: To investigate the status of ultrasonic bone density in the population of normal children aged 6 to 12 years old in Shenzhen City and establish a normal reference index of ultrasonic bone density of this population. DESIGN: Cross-sectional survey. SETTING: Ultrasound Department of People's Hospital in Longgang District of Shenzhen City. PARTICIPANTS: The volunteers for ultrasonic bone density detection were chosen froma kindergarten, an elementary school and a middle school between March 2002 and April2003. Excluded were those who had bone fracture and received medication of hormone and other drugs within 6months that affected bone metabolism, and menstrual history. Altogether we chose 697 normal children, 367 boys and 330 girls whose age ranged from 6 to 12 years old. METHODS: SAHARA ultrasonic bone density apparatus (the US) was used, and corrected according to the standard body model after the operation began.The error of precision was below 1％ and the error of accuracy was 3％. Bone density of the left heel of the children was detected and body mass (kg) and height (cm) were also measured using the same height and weight scale. MAIN OUTCOME MEASURES: The correlation between bone densityof the heel and sex, age and body mass in the population of normal children aged 6 to 12 years. RESULTS: The normal reference values of bone density in the population from 6 to 12 years old were (0.445±0.166) g/cm2 in 6-year-old group,(0.509±0.151) g/cm2 in 7-year-old group, (0.510±0.133) g/cm2 in 8-year-old group, (0.519±0.132) g/cm2 in 9-year-old group, (0.520±0.153) g/cm2 in 10-year-old group, (0.53±0.175) g/cm2 in 11-year-old, and (0.545±0.206) g/cm2 in 12-year-old group. There were differences in bone density between boys and girls (P ＜ 0.001), and after correction by body mass, the difference disappeared. Bone density of the boys and girls had increasing linear correlation with age (male r=0.722, P ＜ 0.001; female r=0.785, P ＜ 0.001), and had significant relationship with body mass (r=0.984, P ＜ 0.001). CONCLUSION: In normal children aged 6 to 12 years old, bone density of the heel has no association with sex, but has increasing linear correlation with age and significant relationship with body mass.

Objective To investigate and evaluate the effects of different test methods on the results of Chlamydia trachomatis detection .Methods Enzyme-linked immunosorbent assay(ELISA) method and the immune colloidal gold technique were adopted to detect the Chlamydia trachomatis in 354 specimens .Results Compared the detection results of ELISA and immune colloidal gold technique ,differences of detection rates of overall specimens and female specimens was not statistically significant (P>0 .05) .The positive rate of male specimens detected by ELISA was 11 .02% (13/118) ,which was significantly higher than that of female speci-mens[4 .2% (5/118)](P<0 .05) .Conclusion The specificity and sensitivity of ELISA were higher than those of immune colloidal gold technique ,which is important for the early diagnosis of male urethral Chlamydia trachomatis infection .

Objective To investigate the correlation between esophageal motility abnormalities and the characteristics of gastroesophageal reflux in patients with different subtypes of refractory gastroesophageal reflux disease (rGERD).Methods From September 2015 to May 2016,a total of 100 rGERD patients were collected,all of whom received gastroendoscopy examination,high resolution manometry (HRM) and 24 h impedance-pH monitoring.According to the results of gastroendoscopy examination,the patients were divided into refractory non-erosive reflux disease (NERD) group and refractory reflux esophagitis (RE) group.Abnormal esophageal motility and pathological gastroesophageal reflux of each group were analyzed.Chi-square test,t test and sum-rank test were performed for comparison,the correlation factors were analyzed by multivariate unconditional Logistic regression.Results Among the 100 patients with rGERD,there were 83 cases in refractory NERD group and 17 in refractory RE group.The episodes of weak acid and gas-liquid mixed reflux of refractory NERD group were both significantly higher than those of refractory RE group (80.2±56.9 vs 44.8± 13.7,56.0± 25.6 vs 25.2±16.1);and the differences were statistically significant (t=3.202 and 2.229,both P＜ 0.05).The DeMeester score,acid reflux episodes and the percentage of reflux time of refractory NERD group were all significantly lower than those of refractory RE group (24.2±8.5 vs 56.8±3.0,21.4± 11.8 vs 35.9 ± 32.6,(7.1 ± 1.6) ％ vs (16.2 ± 8.8) ％),and the differences were statistically significant (t=-2.820,-2.230 and-2.604;all P＜0.05).However,the average resting pressure of lower esophageal sphincter was higher than that of refractory RE group ((7.9±5.6) mmHg (1 mmHg=0.133 kPa) vs (4.5±2.2) mmHg),and the difference was statistically significant (t=2.443,P＜0.05).Patients with esophageal motility disorders of refractory NERD group and refractory RE group were 58 cases (69.9 ％) and 12 cases (12/17),respectively,and the difference was not significant (P＞0.05).Compared with refractory RE group,the ratio of intermittent contraction was higher (1/17 vs 26.5％,22/83) and the peristaltic contraction disorder was lower in refractory NERD group (11/17 vs 43.4％,36/83);and the differences were statistically significant (x2 =3.389 and 2.587,both P ＜ 0.05).The results of multivariate non-conditional Logistic regression analysis showed that intermittent contraction and gas reflux were risk factors of the incidence of pathological weak acid reflux (odd ratio (OR) =3.139 and 1.254,both P＜0.05),while body mass index and gas-liquid mixed reflux were the risk factors of the occurrence of pathological acid reflux (OR =1.302 and 1.026,both P＜ 0.05),whereas the distal contractile integral was a protective factor (OR=0.998,P＜0.05).Conclusion Esophageal dysmotility is common in patients with rGERD,and the dysmotility disorders are different in patients with different subtypes,which may be related to the different reflux characteristics.

Objective:To explore the quality of life and psychological factors of patients with refractory gastroesophageal reflux disease (rGERD).Methods:From September 2016 to March 2019, 159 rGERD patients visiting the Department of Gastroenterology, Beijing Tongren Hospital Affiliated to Capital Medical University were retrospectively selected. According to the presence or absence of distal esophageal mucosal injury under gastroscopy, the patients were divided into refractory reflux esophagitis (RE) group (58 cases) and refractory non-erosive reflux disease (NERD) group (101 cases). The general data, the results of 24 h esophageal impedance pH, esophageal high-resolution manometry (HRM) and the scores of gatroesophageal reflux disease-questionnaire (GerdQ), 36-item short-form health survey (SF-36), self-rating anxiety scale(SAS) and self-rating depression scale (SDS) were recorded and compared between the two groups. Independent sample t test, rank sum test, chi-square test and multiple linear regression analysis were used for statistical analysis. Results:There were no significant differences in gender, age, abdominal circumference or body mass index between the two groups (all P>0.05). The incidence of extraesophageal symptoms of refractory NERD group was higher than that of refractory RE group (45.5%, 46/101 vs. 24.1%, 14/58), and the difference was statistically significant ( χ2=7.185, P=0.010). The episodes of gas reflux, weak-acid reflux and non-acid reflux were all more than those of refractory RE group (66.20 times, 45.20 times to 111.60 times vs. 38.40 times, 23.50 times to 59.63 times; 34.70 times, 9.05 times to 52.75 times vs. 6.35 times, 3.10 times to 24.00 times; 12.60 times, 2.15 times to 24.20 times vs. 2.15 times, 0 times to 10.30 times), GerdQ score of refractory NERD group was higher than that of refractory RE group (8.9±2.5 vs. 7.8±2.3), and DeMeester score, the symptom index and symptom association probability of refractory NERD group were all lower than those of refractory RE group (5.16, 1.75 to 14.48 vs. 15.19, 2.78 to 45.96; 33.3%, 0 to 60.0% vs. 57.5%, 40.5% to 78.0%; 87.8%, 0 to 97.8% vs. 94.0%, 82.7% to 98.2%); and the differences were statistically significant ( Z=-5.548, -5.384 and -4.338, t=3.306, Z=-2.607, -4.313 and -2.468; all P<0.05). The esophageal distal contractile integral of refractory NERD group was lower than that of refractory RE group (334.0 mmHg·s·cm, 182.5 mmHg·s·cm to 492.0 mmHg·s·cm vs. 399.0 mmHg·s·cm, 216.5 mmHg·s·cm to 756.3 mmHg·s·cm, 1 mmHg=0.133 kPa), and the difference was statistically significant ( Z=-2.204, P=0.030). There were no significant differences in lower escophageal sphincter or the length of peristaltic interruption between the two groups (both P>0.05). There were no significant differences in physical functioning, role-physical, bodily pain, general health, vitality, social functioning, role-emotional, mental health or reported health transition of SF-36 score between refractory NERD group and refractory RE group (all P>0.05). Among 159 patients with rGERD, 98 patients (61.6%) had anxiety and 55 patients (34.6%) had depression. The SAS score of refractory NERD group was higher than that of refractory RE Group (52.6±5.8 vs. 47.0±8.8), and the difference was statistically significant ( t=4.794, P<0.05), however there was no significant difference in SDS score between the two groups ( P>0.05). The results of multiple linear regression analysis showed that GerdQ score in rGERD patients was positively correlated with DeMeester score, gas reflux, weak acid reflux, SAS score and SDS score ( r=0.201, 0.228, 0.171, 0.229 and 0.276; all P<0.05). Conclusions:Among the patients with rGERD, the reflux symptoms are more severe in refractory NERD patients, which may be related to non-acid reflux, gas reflux, esophageal motor disorders, and psychological abnormalities, especially anxiety.

Objective To analyze the relationship between body type,age,gender,esophageal motility function,lower esophageal sphincter pressure (LESP) and clinical classification and type of reflux contents of patients with gastroesophageal reflux disease (GERD).Methods From September 2015 to July 2016,at Beijing Tongren Hospital of China Capital Medical University,the results of 24-hour esophageal impedance-pH monitoring of 141 patients with GERD were retrospectively analyzed.The differences of reflux contents were compared in patients with GERD among different body type,age,gender,esophageal motility function,LESP and clinical classification.Mann-Whitney test was performed for comparison between groups.Results Acid reflux was more common in obese patients (body mass index more than 23.9 kg/m2) compared with patients with normal body type (body mass index from 18.5 to 23.9 kg/m2) (18.5,7.0 to 45.3 vs.10.0,2.0 to 32.0),and the difference was statistically significant (Z =-2.320,P =0.020).Patients under 65 years old had more numbers of weak acid reflux,non-acid reflux and gas reflux than patients over 65 years old (58.5,32.8 to95.0 vs.40.0,24.0to71.0;19.5,6.0to47.5 vs.8.0,3.0 to19.0;46.0,23.8to79.3 vs.35.0,11.0 to 56.0),and the differences were statistically significant (Z =-2.690,-3.286 and-2.091,all P＜0.05).Male patients had more gas and mixed reflux compared with female patients (53.5,24.0 to 122.8 vs.36.0,19.0 to 67.0;34.0,20.8 to 50.0 vs.27.0,14.0 to 43.0),and the differences were statistically significant (Z =-2.424 and-1.961,both P ＜ 0.05).There was no statistically significant difference in reflux contents between patients with normal esophageal motility and patients with esophageal motility disorder (weak or interrupted peristalsis) (all P ＞ 0.05).Patients with reflux esophagitis(RE) and/or Barrett's esophagus (BE) had more weak acid reflux,non-acid reflux and gas reflux compared with patients with non-erosive reflux disease (NERD) (61.0,31.3 to 102.5 vs.44.0,24.5 to 66.5;18.0,8.0 to 36.5 vs.8.0,2.0 to 22.0;49.5,27.5 to 86.5 vs.26.0,11.0 to 47.0),and the differences were statistically significant (Z =-2.585,-2.942 and-3.278,all P ＜ 0.05).Patients with lower esophageal sphincter (LES) relaxation were more likely to have weak acid reflux than patients with normal LES function (57.0,32.3 to 87.0 vs.40.0,21.0 to 73.0),the difference was statistically significant (Z =-2.065,P =0.039).Conclusion Body type,age,gender,LESP and clinical classification are related to type of reflux contents in GERD patients,while esophageal peristalsis is irrelevant.