Objective:To investigate age-related morphological changes of the pancreas in healthy people using magnetic resonance imaging(MRI).Methods:From January 2017 to October 2019, people who took physical examinations at our hospital were enrolled and were divided into 7 groups according to age: 20-29 years old, 30-39 years old, 40-49 years old, 50-59 years old, 60-69 years old, 70-79 years old and ≥80 years.Also, the former four groups were classified as young and middle-aged(<60 years old)and the latter three as the elderly(≥60 years old). Morphological characteristics of the pancreas in each group were examined via MRI.Differences in parameters such as anteroposterior diameters of the head, body and tail and the pancreatic volume between the groups and the relationship between these parameters and age were analyzed.Results:A total of 191 cases who met the inclusion criteria were enrolled, including 96(50.3%)males and 95(49.7%)females, with 28 aged 20-29 years, 28 aged 30-39 years, 27 aged 40-49 years, 26 aged 50-59 years, 30 aged 60-69 years, 28 aged 70-79 years and 26 aged ≥80 years.There were 109 cases in the young and middle-aged category and 82 cases in the elderly category.MRI findings included pancreatic atrophy, which was most obvious in the tail; uneven and serrated edges of the pancreas and pancreatic lobulation; uneven signal intensity in the T 1-and T 2-weighted sequences; the "crispening effect" of pancreatic steatosis in the opposed-phase T 1-weighted sequences, and a trend of widening of the main pancreatic duct.The anteroposterior diameters of the pancreatic head, body and tail and the pancreatic volume reached the peak at(28.21±4.55)mm, (24.00±4.45)mm, (24.91±5.08)mm and(100.91±27.44)cm 3 between 30-39 years of age, and then gradually decreased to(18.87±3.82)mm, (15.63±3.96)mm, (13.70±3.70)mm and(43.88±10.47)cm 3 in those aged ≥80 years, with a decrease of 33.10%, 34.88%, 45.00% and 56.51%, respectively.The anteroposterior diameters of the pancreatic head, body, tail and the pancreatic volume in the elderly were(21.59±4.35)mm, (18.10±4.29)mm, (17.00±4.56)mm and(59.85±22.73)cm 3, which were smaller than those in the young and middle-aged category[(26.18±4.57)mm, (22.10±4.64)mm, (22.42±4.71)mm and(90.09±25.06)cm 3], and the differences were statistically significant( t=7.12, 6.19, 8.10 and 8.71, respectively, all P<0.001). The anteroposterior diameters of the head, body and tail and the pancreatic volume were negatively correlated with age( r=-0.52, -0.45, -0.56 and -0.57, respectively, P<0.001). Conclusions:The anteroposterior diameters of the head, body and tail and the pancreatic volume reach the peak between 30-39 years of age, and then gradually start to decline with the increase of age.After age 60, the decline become more evident, showing morphological signs of degeneration and dilatation of the main pancreatic duct.

To analyze the lesion distribution situations and relationship of lesions detected by gastroscopy and colonoscopy in asymptomatic population in Beijing. Data of 1 663 patients who received gastroscopy and colonoscopy in the physical examination center of Peking Union Medical College Hospital and Beijing Hospital between January 2016 and December 2018 were analyzed retrospectively. Statistical analysis was conducted on the detection rate and relationship of different lesions based on the information of gender and ages. Gastroscopy data showed that chronic non-atrophic gastritis and chronic atrophic gastritis accounted for 1 240 (74.6%)and 423 (25.4%)cases respectively. Chronic atrophic gastritis was more common in population aged over 40. Other common diseases included erosions of gastric body and/or antrum, fundic gland polyps, reflux esophagitis, duodenitis, bile regurgitation and so on. Upper gastrointestinal tumors including esophagus cancer and gastric cancer were both early lesions. Colonoscopy results showed that colonic polyps were common lesions, among which there were 382 (23.0%)cases of colonic adenoma and 217 (13.0%)hyperplastic polyps. Incidence of colonic polyps increased with age. Colorectal cancer accounted for 0.7%. Colon diverticulum and melanosis coli were more common in population aged over 40. Colon adenoma was more common in male and melanosis coli was more common in female. The positive rate of HP was 32.2%. There was no positive relationship between HP infection and fundic gland polyps( P=0.329). There was no positive relationship between fundic gland polyps and colon adenomas as well as colorectal cancer( P=0.152, P=0.616). Gastroscopy and colonoscopy play important roles in different kinds of digestive diseases, especially in the early detection of tumors. More attention should be paid to the application of endoscopy in asymptomatic population.

Background: Thyroid diseases are highly prevalent worldwide, but their diagnosis remains a challenge. We established reference intervals (RIs) for thyroid-associated hormones and evaluated the prevalence of thyroid diseases in China. Methods: After excluding outliers based on the results of ultrasound screening, thyroid antibody tests, and the Tukey method, the medical records of 20,303 euthyroid adults, who visited the Department of Health Care at Peking Union Medical College Hospital from January 2014 to December 2018, were analyzed. Thyroid-associated hormones were measured by the Siemens Advia Centaur XP analyzer. The RIs for thyroid-associated hormones were calculated according to the CLSI C28-A3 guidelines, and were compared with the RIs provided by Siemens. The prevalence of thyroid diseases over the five years was evaluated and compared using the chi-square test. Results: The RIs for thyroid stimulating hormone (TSH), free thyroxine (FT4), free triiodothyronine (FT3), total thyroxine (TT4), and total triiodothyronine (TT3) were 0.71–4.92 mIU/L, 12.2–20.1 pmol/L, 3.9–6.0 pmol/L, 65.6–135.1 nmol/L, and 1.2–2.2 nmol/L, respectively. The RIs of all hormones except TT4 differed significantly between males and females. The RIs of TSH increased with increasing age. The prevalence of overt hypothyroidism, overt hyperthyroidism, subclinical hypothyroidism, and subclinical hyperthyroidism was 0.5% and 0.8%, 0.2% and 0.6%, 3.8% and 6.1%, and 3.3% and 4.7% in males and females, respectively, which differed from those provided by Siemens. Conclusions Sex-specific RIs were established for thyroid-associated hormones, and the prevalence of thyroid diseases was determined in the Chinese population.

Objective To optimize the process of ultrasonic extraction of polysaccharide in Anoectochilus roxburghii and to investigate the method of protein removal. Methods The extraction rate of polysaccharide was used as the detection index. On the basis of single factor investigation, Box-Behnken experimental design and response surface method were used to optimize the three factors of material-liquid ratio, ultrasonic time and ultrasonic extraction temperature. The five deproteinization methods including Sevage reagent method, TCA method, salt method (NaOH-CaCl₂ and NaOH-NaCl) and hydrochloric acid method were investigated with the retention rate of polysaccharide and protein removal rate. Results The optimal extraction conditions of polysaccharide from Anoectochilus roxburghii were as follows: liquid-to-solid ratio was 10∶1, extraction temperature was 48 ℃ and extraction time was 36 min with extraction 2 times, ultrasonic power was 300 W, the extraction rate was 13.13%. NaOH-CaCl₂ deproteinized methods∶ the loss rate of polysaccharide was 18.74%, and the removal rate of protein was 95.62%. Conclusion Ultrasonic extraction is easy to operate, and the optimized extraction method can achieve a high extraction rate. NaOH-CaCl₂ deproteinization methods can get high protein removal rate and polysaccharide retention rate. This method is suitable for the research and development of the active components of the polysaccharides from Anoectochilus roxburghii.

Objective To explore the effect and compare the relapse rates of 1-desamino-8-D-Arginine Vasopressin(DDAVP) different withdrawal ways after initial 3 months in primary monosymptomatic nocturnal enuresis(PMNE) patients,in order to provide some evidences and references to use DDAVP to cure PMNE preferably.Methods Two hundred and fifty-six cases PMNE patients who were treated in Hubei Maternal and Child Health Hospital from November 2014 to June 2016 were selected and randomly divided into group A (DDAVP immediate withdrawal group,65 cases),group B(DDAVP day reduction group,58 cases) and group C (DDAVP step reduction group,60 cases).All patients were given DDAVP tables for 3 months.After 3 months for DDAVP,patients who were effective (full respond and partial respond) to DDAVP continued to undergo a withdrawal stage,those in group A underwent immediate cessation,those in group B continued to receive the effective dose every other day for 2 months and those in group C were step by step tapered by 0.05-0.10 mg every 2-4 weeks until completely stopped,the period was not more than 3 months.All patients had a follow-up visit for 3 months after cessation of DDAVP.Results A total of 183 patients completed the study finally,there were 65 patients in group A,58 patients in group B and 60 patients in group C.Initial 3 months the effective rates of group A,B and C were respectively 89.23％ (58/65),89.66％ (52/58) and 86.67％ (52/60),there were not statistically significant difference(x2 =0.309,P =0.857).There were 58 patients in group A,52 patients in group B and 52 patients in group C continued to undergo the withdrawal stage.One month after cessation of DDAVP,the effective rates of group B (88.46％,46/52) and group C (92.31％,48/52) were significantly higher than group A(67.24％,39/58) (x2 =7.030,P=0.008;x2 =10.417,P=0.001),while the relapse rates of group B(19.23％,10/52) and group C(17.31％,9/52) were significantly less than group A(36.21％,21/58) (x2=3.904,P=0.048;x2=4.937,P =0.026).Three months after cessation of DDAVP,the effective rates of group C (78.85％,41/52) were significantly higher than group A (50.00％,29/58) and group B (57.69％,30/52) (x2 =9.859,P=0.002;x2 =5.371,P=0.020),and the relapse rates of group C(32.69％,17/52) were significantly less than group A (55.17％,32/58) and group B (51.92％,27/52) (x2 =5.609,P =0.018;x2 =3.939,P =0.047),while the effective rates and relapse rates were not statistically significant difference between group A and group B(x2 =0.652,P =0.419;x2 =0.116,P =0.733).Severe adverse events related to DDAVP were not observed in any patients.Conclusion Gradual withdrawal after initial 3 months of DDAVP may improve the effect and reduce the relapse rates,the short-term and long-term curative effects of step-by-step withdrawal treatment are both well,while long-term curative effects of every other day withdrawal treatment is not obviously well.

Objective To observe the incidence of fragmented QRS complex (fQRS)and ST Segment depression fQRS (STD fQRS)during the first 48 hours after non-ST elevation myocardial infarction(NSTE MI)and discuss the value of predicting mortality in patients with NSTE MI .Methods Based on the ECGs ,the patients with NSTE MI were divided into two groups :fQRS and non fQRS group .And then fQRS group was divided into two sub-groups :STD fQRS and non-STD fQRS group .Their mortality was studied during long-term follow-up .Results (1)731 patients with NSTE ACS [the NSTE MI group(n=609) and the UA group(n=122)] were studied .The incidence of fQRS in the NSTE MI group was higher than that of the UA group .(2)All cause mortality in the fQRS group were higher than that in the non-fQRS group ,and all-cause mortality in the STD fQRS group were higher than that in the non-STD fQRS group ,all the above results were not only in the early stages of NSTE MI ,but also in the long term fol-low-up .(3) Multivariate Cox regression analysis revealed that STD fQRS was an independent significant predictor for all cause mortality ,but not of the fQRS .Conclusion The STD fQRS may be an independent predictor of mortality in patients with NSTE MI .

Objective To Evaluate the performance of serum adenosine deaminase assays of different manufacturers and explore the approach for harmonization of test results.Methods It was evaluated the indice including the limit of blank ,precision,linearity range and reference interval of 10 test systems.It was as the reference system by Mindray test system to evaluate the comparability and the difference of ADA results among 10 different systems.The evaluation was performed before and after calibration by a selected fresh serum assigned by the reference system.A commercial calibrator of the minimum matrix effect was selected from 8 different calibrators as the long-term calibrator to harmonize the ADA results of 10 systems.Results The results of LoB were 0.1-6.3 U/L,respectively.The within-run CVs and total CVs of 10 systems were all less than 5%and actual linearity ranges were conformed to claims of manufacturers.After calibration with fresh serum calibrator ,the averaged difference of 10 test systems was reduced from 14% to 3.0%, and the average difference was 1.8% after calibration with long-term calibrator.The common reference interval of all test systems was 5-24 U/L identically.Conclusions The comparability of ADA measurements can be improved by using a common human serum calibrator and the commutable commercial calibrator.And it is necessary and feasible to develop the standardzation of ADA.

Objective To discuss the feasibility of enzymatic reference methods in Routine Chemistry external quality assessment (EQA)inlaboratorymedicine.Methods Samplesofthe1stEQAin2012byNationalCenterforClinicalLaboratories(NCCL)and patients′sera were measured by reference methods and 5 clinical analytic systems for the catalytic activity of CK ,LDH ,ALP ,ALT , AST ,GGT and AMY ,then the results of 5 clinical systems were compared with the reference methods′or target value of NCCL by calculating the bias ,and evaluated them according to the criteria of EQA by NCCL .Results The results of EQA samples measured by reference methods was within ± 10% compared with NCCL target value .Compared with the results of reference method ,the through put was 100 .0% for wet clinical chemistry systems measuring both EQA samples and patients′serum ,and the dry clinical chemistry systems was 77 .1 for EQA samples and 97 .1% for patients′serum according to the criterion of EQA ,and the through put was 72 .9% and 63 .6% of wet clinical chemistry systems according to the standard of enzymatic trueness of NCCL .Conclusion Reference method could be applied to EQA ,and will be a great help for the trueness of clinical testing .

Objective To evaluate the measurement accuracy of serum gamma-glutamyltransferase (GGT) assays manufactured in China. Methods The International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) reference method for GGT was set up and, after verification, was used to evaluate the performance of routine assay systems made in China. The evaluation was performed twice before and after a calibration by a common serum calibrator. Results For the reference measurement, the within run and total CVs were all less than 1%. The biases with the target values of IFCC External Quality Assessment Scheme for Reference Laboratories (RELA) were all within the limit of equivalence. Before a calibration with a common calibrator, the largest biases of results of GGT of the routine tasting systems compared with reference method at three medical decide levels were -47.53%, -34.11% and -30.07% respectively, and the averaged biases were 14.53% ,12.88% and 12.48%. After calibrating by fresh serum calibrator,the largest biases were reduced to - 17.63%, -5.88% and -4.08% ,the averaged biases were reduced to 7.50%, 2.70% and 1.87%. Conclusion The performance of GGT measurements can be effectively improved by using a common fresh serum calibrator that has a value assigned with the reference method.

Objective To explore the effects of 75 mGy irradiation on the apoptosis of spermatogenic cells and antioxidant capacity of serum and testis and hormone levels in male rats with diabetes mellitus(DM).Methods Rats were injected intraperitoneally with streptozotocin(STZ)to develop diabetes.The diabetic rats were irradiated with 75 mGy X-rays every other day for 4 weeks.Their survival rate and body weight were recorded 12 weeks after development of diabetes.The apeptosis percentage of germ cells was measured with flow cytometry and TUNEL method.The changes of anti-oxidation and gonadal hormone levels in serum and testis were measured with kits.Results After the rats suffered from diabetes for 12 weeks,the survival rate in DM group was 25%(6/24),100% in normal control group(16116).The survival rate in 75 mGy + DM group(9/16,56.25%)was obviously higher than that in the DM group(X2= 4.00,P < 0.05).Meanwhile,the percentage of apaptotic spermatogenic cells in the diabetic rats was significantly larger than those in the normal control and irradiation groups(F = 5.496,P < 0.05).MDA and NO levels in serum and testis of diabetic rats were higher in varying degrees than that in the normal control,while the serum and testis MDA content in the 75 mGy + DM group were lower than those in the DM group especially in the testis(F = 10.644,P < 0.01).75 mGy X-ray irradiation decreased NO content in the diabetic rats serum significantly(F = 14.379,P < 0.05)and increased NOS activity and TS,FSH level(F = 9.676,43.194 and 5.282,respectively,P < 0.05 and P < 0.01).Conclusions LDR could decrease the MDA level and NO content,and increase the antioxidant enzyme activity and TS and FSH levels in testis and serum of diabetic rats.