The China National Health Survey (CNHS) is the first nationwide multi-ethnic cross-sectional interview and health examination conducted from 2012 to 2017. The survey is designed to study reference intervals for physiological constants as well as determinants of noncommunicable diseases among different ethnic populations in different areas, so that the data can be used to enhance clinical diagnosis strategies and health promotion. CNHS used a stratified, multistage cluster sampling method to obtain a sample of 53 895 people aged 20-80 years in 10 ethnic groups from 11 provinces or autonomous regions all over China. Blood samples were collected from each participant for the establishment of the China Multi-Ethnic Biobank (CMEB). CNHS collected data on demographic and socioeconomic information, lifestyle factors, anthropometric measures, laboratory tests and clinical profiles. These data provide a comprehensive resource for further study on risk factors of noncommunicable disease among different ethnic groups. Information about the CNHS database, including publication list, introduction of the survey design and methods, and guidelines for submitting electronic forms of data application, is available at [http://www.bmicc.cn/web/share/home].

ATP-sensitive K+ (KATP) channel subunits on the subcellular structures of rat cardiomyocytes were studied with antibodies against Kir6.1 and Kir6.2. According to the results of Western blot analysis, Kir6.1 was strongly expressed in mitochondrial and microsome fractions, and faintly expressed in cell membrane fraction, whereas Kir6.2 was mainly expressed in the microsome fraction and weakly in cell membrane and mitochondrial fractions. Immunohistochemistry showed that Kir6.1 and Kir6.2 were expressed in the endocardium, atrial and ventricular myocardium, and in vascular smooth muscles. Immunoelectron microscopy revealed that Kir6.1 immunoreactivity was mainly localized in the mitochondria, whereas Kir6.2 immunoreactivity was mainly localized in the endoplasmic reticulum and a few in the mitochondria. Both Kir6.1 and Kir6.2 are candidates of mitochondrial KATP channel subunits. The data obtained in this study will be useful for analyzing the composition of KATP channels of cardiomyocytes and help to understanding the cardioprotective role of KATP channels during heart ischemia.

AimsTo investigate the prevalence, ethnic differences and associated risk factors for pterygium in Han and Manchu populations aged 40–79 years in Hebei province, China.DesignCross-sectional study, as a part of the China National Health Survey.SettingHebei province, China.ParticipantsA multistage cluster sampling method with urbanisation level-based stratification was used to select participants for this study. A total of 4591 individuals over 40 years were recruited for this study. Inclusive criteria: (1) residents who had been living in Hebei for more than 1 year; (2) Han individuals with both parents being Han, or Manchu individuals with both parents being Manchu; (3) underwent ophthalmic examinations and (4) information in the questionnaire was complete.Main outcome measuresMultiple logistic regression analysis was used to evaluate the association between pterygium prevalence and factors of interest.ResultsA total of 3790 individuals (2351 Hans and 1439 Manchus) met the study criteria, of which 248 were diagnosed with pterygium (6.5%). There was no significant difference between the prevalence rates in Hans (6.2%) and Manchus (7.2%) (p=0.232). Multivariate analysis revealed that the risk factors for grade 2 or higher pterygium were increasing age (p<0.001) and rural residence (OR 1.83; 95% CI 1.11 to 3.02; p=0.018), while the protective factors include gender (female) (OR 0.58; 95% CI 0.37 to 0.88; p=0.011), cigarette smoking (OR 0.53; 95% CI 0.34 to 0.83; p=0.005) and myopia (OR 0.50; 95% CI 0.33 to 0.77; p=0.002). Premature menopause (OR 2.66; 95% CI 1.05 to 6.72; p=0.038) increased the risk of grade 2 or higher pterygium in females, while higher high-density lipoprotein (HDL) (OR 1.94; 95% CI 1.08 to 3.47; p=0.027) was a risk factor of grade 2 or higher pterygium in males.ConclusionThe overall prevalence of pterygium in Han and Manchu population in Hebei, China was approximately 6.1%. There were no differences in the prevalence of pterygium between Hans and Manchus, and the race was not a risk factor. This is the first study to report on the positive association between premature menopause and pterygium in females and between higher HDL levels and pterygium in males.

Background The present study was the first one aimed to investigate the current muscle fitness and its associated factors among children and adolescents in mainland China. Methods From Nov 2013 to Jul 2014, 2283 children and adolescents aged 7–18 were recruited in Hainan and Shaanxi Provinces in China by cross-sectional design. Information on anthropometry and muscle fitness, measured by hand grip strength (GS), vertical jump (VJ) and sit-and-reach (SR), were collected. Analysis of covariance was performed by using general linear regression models to identify the association between BMI and muscle fitness. Results The means of GS, VJ and SR in boys were 22.30 ± 11.55 kg, 22.93 ± 6.80 cm and 3.58 ± 7.31 cm, respectively, and in girls were 16.61 ± 6.87 kg, 18.11 ± 4.08 cm and 7.18 ± 5.72 cm, respectively. GS (from 8.26 kg in the 7–8-year-old group to 27.91 kg in the 17–18 group) and SR (from 1.75 cm in the-8-year-old group to 10.12 cm in the 17–18 group) increased with age (both p for trend < 0.001). Boys had higher GS and VJ, but significantly lower SR than girls in each age group ( p < 0.001). After adjusting for age, sex, residential areas and study regions, GS increased with elevated BMI (compared with normal weight group, the regression coefficient for thinness and overweight/obesity were − 2.997(95%CI: −3.693 to − 2.301) and 1.220 (95%CI: 0.285 to 2.155), respectively. With the p values less than 0.001 and 0.011, respectively). For VJ, there was no difference found between normal weight group and overweight/obesity group ( p = 0.550), but the thinness group had the lowest performance (regression coefficient = − 2.681, 95%CI from − 3.965 to − 1.397, p < 0.001). For SR, compared with normal weight group, the regression coefficients for thinness and overweight/obesity were − 1.313(95%CI: −2.228 to − 0.399) and − 1.623(95%CI: −3.216 to − 0.030) respectively, both p < 0.05. Conclusions Increased body weight may have a positive association with isometric muscle strength measured by grip strength, but a negative one with strength of lifting the body. Sex difference was also found in the performance of flexibility. Electronic supplementary material The online version of this article (10.1186/s12887-019-1477-8) contains supplementary material, which is available to authorized users.