To investigate the prenatal sonographic feature in the early diagnosis of amniotic band syndrome at 11 －14 weeks′ gestation . Methods A retrospective study was conducted to analysis and summarize the ultrasonographic features of 4 fetuses without band‐like echoes in amniotic cavity at 11－14 weeks′gestation ,but verified as amniotic band syndrome in Peking Union M edical College Hospital . Results T wo cases ( cases 1 ,2) showed the fixed head position with skull defect and intracranial structure disorders . Cases 3 and 4 showed one upper limb in a fixed position ,and the hand seemed to adhere to the umbilical cord isolatedly . In addition ,case 1 showed complete chorioamniotic membrane separation . T here were multiple band‐like echoes adhered to body of 3 fetals during the follow‐up scan at 14 －18 weeks . T he parents of cases 1 and 2 chose to terminate the pregnancy after counseling ,the other 2 cases also induced labor due to intrauterine fetal death at 15+2 weeks and 19+2 weeks respectively . All 4 cases were confirmed as amniotic band syndrome by pathology . Conclusions When the fetal sonographic images showed fixed head position ,disordered intracranial structure ,or adhesion between umbilical cord and hand with limited movement at 11 －14 weeks′ gestation ,it should be paid attention to observing the band‐like echoes and followed up closely to prevent missed diagnosis of amniotic band syndrome .

Objective:To evaluate the placental micro-vascular circulation by microvascular flowing imaging (MVFI) method, and to explore the clinical value of microvascular index (MVI) for the diagnosis of fetal growth restriction (FGR).Methods:A total of 21 fetuses at 24-34 weeks of gestation at the Peking Union Medical College Hospital from October to November 2019 were enrolled in this study, including 7 fetal growth restriction (FGR) fetuses, and 14 normal fetuses as control group. The fetuses of the two groups were matched according to the gestational weeks at the ratio of 1∶2. Fetal biometry parameters were measured and the placenta was observed by two-dimensional ultrasound.Uterine artery pulse index (UtA-PI), middle cerebral artery pulse index (MCA-PI), and umbilical artery S/D ratio were evaluated by color and pulse-wave Doppler. The placenta mico-circulation was displayed by the MVFI method and MVI was measured.Results:The study included 14 normal fetuses and 7 FGR fetuses. Compared with the control group, more placenta in the FGR group manifested as thickened and heterogeneous with decreased MVI and increased UtA-PI. There was statistically significant difference in placental mean MVI between two groups ( P=0.044). Besides, a trend towards significant negative correlation was observed between MVI and placenta thickness, although this was not statistically significant ( rs=-0.35, P=0.065). MVI had a higher specificity (100%) in the prediction of FGR. Conclusions:MVFI can display the micro-circulation of the placenta, and provide a direct and quantitative assessment method for placental perfusion.

Chronic diseases have become an important public health problem for people under 70 years of age worldwide， while also causing a great economic burden. The establishment of clinical prediction models can help to predict the risk of a disease or the prognostic effect of a study subject in advance by means of index testing at the early stage of chronic diseases， and plays an increasingly important role in clinical practice. This study introduces clinical diagnostic prediction models and clinical prognostic prediction models， and reviews clinical data processing， clinical prediction model building， visualization methods and model evaluation from the perspective of the application of clinical prediction models， which contribute to the correct and reasonable use of prediction models in clinical research.

ObjectiveTo analyze the prevalence of reduced visual acuity of young children in Changning district of Shanghai and to explore the influencing factors， so as to provide a reference basis for formulating prevention and control measures for children’s reduced visual acuity. MethodsVisual acuity examination and questionnaire survey were conducted on 5 772 middle class children in kindergartens and first grade children in primary schools who participated in the refractive screening in Changning District in 2019. χ² test and logistic regression analysis were used to explore the influencing factors of reduced visual acuity. ResultsThe overall prevalence of reduced visual acuity among lower-aged children was 10.4% （596/5 772）. The prevalence of reduced visual acuity in the first grade children was 10.1% （284/2 822）， and that in the middle class children of kindergarten was 10.8% （312/2 900）. The prevalence of reduced visual acuity was 10.2% （298/2 933） in boys and 10.7% （298/2 789） in girls. 98.1% of young children had one or more bad habits when using eyes. Multivariate logistic regression analysis showed that frequent excessive head lowering （OR=1.713） and sometimes too close to the screen （OR=1.294） were independent risk factors for reduced visual acuity in young children； After stratification by age， frequent excessive head lowering （OR=1.997） increased the risk of reduced visual acuity of children in the first grade of primary school. Premature birth （OR=1.841）， sometimes excessive head lowering （OR=1.363） and frequent excessive head lowering （OR=2.002） increased the risk of reduced visual acuity of children in the middle class of kindergarten. ConclusionFor young children， we should pay more attention to their daily eye use distance， correct their bad behaviors for using eyes such as excessively lowering their head when using eyes and too close to the video screen when using electronic products， so as to prevent and delay the occurrence and development of reduced visual acuity.

ObjectiveTo compare the annual and age trends of the age-standard incidence rate （ASIR） and the age-standard mortality rate （ASMR） of lung cancer in countries with different human development index （HDI） from 1990 to 2019. MethodsThe data were collected from the global burden of disease study and GLOBOCAN 2020. The average annual percentage change （AAPC） and age trends of ASIR and ASMR in lung cancer were analyzed by the Joinpoint regression model， and the comparison between the four groups was analyzed by Kruskale-Wallis analysis. ResultsIn 2020， the incidence and mortality of lung cancer gradually increased with age and HDI grade. From 1990 to 2019， the global ASIR and ASMR of lung cancer decreased， and the ASIR of lung cancer among male decreased， while the ASIR of lung cancer among female increased. The results showed that ASIR of lung cancer in female residents in countries with very high HDI increased significantly from 1996 to 2011， resulting in an overall upward trend in female ASIR， while the other groups showed a downward trend. It was found that ASIR and ASMR of lung cancer in China and India were on the rise， while ASIR and ASMR of lung cancer in Russia and the United States were on the decline. ConclusionAlthough very high/high HDI countries face a higher burden of lung cancer occurrence and death， the accumulation of lung cancer burden is completed in the transitioning period. Therefore， lung cancer prevention measures in countries in transition are critical for global lung cancer control.

Objective: To analyze the clinicopathological features of type 2 diabetes mellitus complicated with colorectal cancer (DCRC). Methods: A case-control study was conducted. Inclusion criteria: (1) hospitalized patients receiving fibrocolonoscopy; (2) adenocarcinoma and mucinous adenocarcinoma diagnosed by pathology; (3) with preoperative cTNM clinical staging; (4) colorectal cancer patients undergoing surgical treatment; (5) with postoperative pTNM staging; (6) no smoking or drinking habits. Exclusion criteria: (1) familial adenomatous polyposis (FAP); (2) Lynch syndrome; (3) carcinoma of anal canal and perianal carcinoma; (4) multiple primary cancer; (5) with serious cardiocerebrovascular diseases or multiple organ failure. Clinicopathlogical data of 32 DCRC patients who were diagnosed and treated in Peking University Shougang Hospital from December 2017 to December 2018 were retrospectively collected and analyzed. Forty nondiabetic colorectal cancer (CRC) patients during the same period were selected as control group according to the sex ratio and the age difference less than 5 years. Student′s t test and χ² test were used to compare the difference between the two groups in baseline clinicopathological data, clinical test results, tumor markers and infiltration status of T cells in tumor immune microenvironment. Results: Among 32 DCRC patients, 24 were males and 8 were females with a mean age of (63.0±1.7) years; among 40 CRC patients, 30 were males and 10 were females with a mean age of (60.5±1.6) years. The duration of diabetes mellitus in DCRC patients (from the diagnosis of diabetes mellitus to the diagnosis of colorectal cancer) was (9.2±1.3) years. The body mass index (BMI) of DCRC group was significantly higher than that of CRC group [(24.8±0.6) kg/m² vs. (23.2±0.4) kg/m², t=2.372, P=0.020]. There were no significant differences in other baseline data (sex, age, primary site of tumor, R0 resection rate, pathological stage, pathological type, differentiation degree of tumor, preoperative intestinal obstruction) between the two groups (all P>0.05). Serum triglyceride level in DCRC group was higher than that in CRC group [(2.1±0.2) mmol/L vs. (1.5±0.1) mmol/L, t=3.085, P=0.003], while hemoglobin [(120.3±5.2) g/L vs. (132.7±2.8) g/L, t=-2.224, P=0.029], anti- thrombin III [(94.2±3.7)% vs. (103.5±2.4)%, t=-2.197, P=0.031], and red blood cell count [(4.2±0.1)×10¹²/L vs. (4.5±0.1)×10¹²L, t=-2.055, P=0.044] were all lower than those in CRC group. The preoperative carcinoembryonic antigen (CEA) level in DCRC group was higher than that in CRC group [(50.3±21.8) μg/L vs. (5.6±1.0) μg/L, t=2.339, P=0.022]. There were no significant differences in preoperative levels of other four tumor molecular markers (CA199, CA242, CA724 and CA125) between the two groups (all P>0.05). The expression of Foxp3 [specific markers of CD4+, CD25+ regulatory T cells (Treg)] in DCRC group was higher than that in CRC group [(82.7±6.2) cell/HPF vs. (62.6±4.9) cell/HPF, t=2.586, P=0.012]. There were no significant differences in the infiltration of CD4, CD8, PD-1 and PD-L1 positive cells between two groups (all P>0.05). Conclusions The average diabetic history of DCRC patients is nearly 10 years. They have higher BMI and serum CEA level, and more Treg cell infiltration in the tumor. Close attention should be paid to these patients in clinical practice.