Objective:To analyze the risk factors of bronchopulmonary dysplasia(BPD)in very preterm infants(VPI), and to provide scientific basis for the prevention and treatment of BPD in VPI.Methods:A prospective multicenter study was designed to collect the clinical data of VPI in department of neonatology of 28 hospitals in 7 regions from September 2019 to December 2020.According to the continuous oxygen dependence at 28 days after birth, VPI were divided into non BPD group and BPD group, and the risk factors of BPD in VPI were analyzed.Results:A total of 2 514 cases of VPI including 1 364 cases without BPD and 1 150 cases with BPD were enrolled.The incidence of BPD was 45.7%.The smaller the gestational age and weight, the higher the incidence of BPD( P<0.001). Compared with non BPD group, the average birth age, weight and cesarean section rate in BPD group were lower, and the incidence of male infants, small for gestational age and 5-minute apgar score≤7 were higher( P<0.01). In BPD group, the incidences of neonatal respiratory distress syndrome(NRDS), hemodynamically significant patent ductus arteriosus, retinopathy of prematurity, feeding intolerance, extrauterine growth restriction, grade Ⅲ~Ⅳ intracranial hemorrhage, anemia, early-onset and late-onset sepsis, nosocomial infection, parenteral nutrition-associated cholestasis were higher( P<0.05), the use of pulmonary surfactant(PS), postnatal hormone exposure, anemia and blood transfusion were also higher, and the time of invasive and non-invasive mechanical ventilation, oxygen use and total hospital stay were longer( P<0.001). The time of starting enteral nutrition, cumulative fasting days, days of reaching total enteral nutrition, days of continuous parenteral nutrition, days of reaching 110 kcal/(kg·d) total calorie, days of reaching 110 kcal/(kg·d) oral calorie were longer and the breastfeeding rate was lower in BPD group than those in non BPD group( P<0.001). The cumulative doses of amino acid and fat emulsion during the first week of hospitalization were higher in BPD group( P<0.001). Multivariate Logistic regression analysis showed that NRDS, invasive mechanical ventilation, age of reaching total enteral nutrition, anemia and blood transfusion were the independent risk factors for BPD in VPI, and older gestational age was the protective factor for BPD. Conclusion:Strengthening perinatal management, avoiding premature delivery and severe NRDS, shortening the time of invasive mechanical ventilation, paying attention to enteral nutrition management, reaching whole intestinal feeding as soon as possible, and strictly mastering the indications of blood transfusion are very important to reduce the incidence of BPD in VPI.

Objective:To investigate the measurements of the ciliary body in patients with acute primary angle-closure (APAC).Methods:This was a case-control study.Subjects were admitted to Ningxia Eye Hospital from January to October 2016.Fifty-five consecutive patients diagnosed with APAC in one eye were presented as case groups, and their fellow eyes were presented as fellow groups.Fifty-five eyes from 55 age-matched normal controls were also recruited as control groups.A-scan ultrasonography and ultrasound biomicroscopy (UBM) were conducted to determine biometric measurements and ciliary body parameters.Biometric measurements included axial length (AL), lens thickness (LT), anterior chamber depth (ACD), pupil diameter (PD), anterior chamber width (ACW) and lens vault (LV). Ciliary body parameters included maximum ciliary body thickness (CBTmax), ciliary body thickness at the point of the scleral spur (CBT 0) and 1 000 μm from the scleral spur (CBT 1000), anterior placement of the ciliary body (APCB), and trabecular-ciliary process angle (TCA), respectively.Pearson correlation analysis was used to examine the correlation between the biometric measurements and the ciliary body parameters.Written informed consent was obtained from each subject before any medical examination.The study protocol was approved by the Ethics Committee of People's Hospital of Ningxia Hui Autonomous Region. Results:The ACD was smaller, while the PD and lens thickness were larger in eyes with APAC compared with their fellow eyes.The differences were statistically significant ( t=-6.805, 3.490, 2.624; all at P<0.05). Smaller AL and ACD measurements were found in the fellow eyes of APAC patients compared with normal eyes, and these differences were statistically significant ( t=-4.828, -6.947; both at P<0.001). For eyes with APAC, their fellow eyes and normal eyes, the average CBT max were (0.907±0.106), (0.960±0.098) and (1.020±0.108)mm; average TCA were (48.99±11.48)°, (51.32±10.87)° and (81.94±12.45)°, respectively.CBT max, CBT 0, CBT 1000, and TCA measukements were smaller, and APCB were larger in eyes with APAC compared with their fellow eyes, and these differences were statistically significant ( t=-5.354, -3.517, -3.407, -0.753; all at P<0.05). In addition, CBT max, CBT 0, CBT 1000, and TCA measurements were smaller, and APCB were larger in the fellow eyes compared with the normal eyes, these differences were also statistically significant ( t=-6.040, -3.132, -6.005, -13.509, 16.795; all at P<0.05). Positive correlations were found between AL and CBT 1000, and between AL and TCA ( r=0.335, P=0.012; r=0.380, P=0.004), while a negative correlation was found between intraocular pressure and CBTmax ( r=-0.289, P=0.032). Conclusions:In eyes with APAC, as well as their fellow eyes, ciliary bodies are thinner and anteriorly rotated, and this anatomical change is associated with shorter AL and high intraocular pressure.

Objective:The research analyzed the current situation and trend of health science and technology innovation in China, developed the national health and health science and technology innovation index to estimate the development of health science and technology innovation in China.Methods:The research discussed the connotation and scope of National Health Science and technology innovation, designed the national health science and technology innovation index, and developed the evaluation index system that covered various aspects including innovation resources, innovation output, innovation environment.Results:The total index and sub-index of national health science and technology innovation index from 2011 to 2017 were calculated. Suppose the base number of 2011 was 100, the value of national health science and technology innovation index in 2017 was 201.73.Conclusions:By using multi-level indicators, the indicators that reflect the basic characteristics of scientific and technological innovation can be transformed into the overall indicators that comprehensively reflect the level of scientific and technological innovation, which can be used to monitor the overall development of health scientific and technological innovation and the situation of each innovation stage.

Objective To examine the prevalence of obstructive sleep apnea (OSA) in patients with acute coronary syndrome (ACS),and to evaluate the relationship of OSA with inflammatory biomarkers in ACS patients.Methods Patients with ACS treated at Beijing Anzhen Hopital from June 2015 to May 2017 were enrolled.Subjects were evaluated for OSA by sleep study,and were divided into a normal-mild OSA group (Apnea Hypopnea Index,AHI ＜ 15 times/h) and a moderate-severe OSA group (AHI ≥ 15 times/h).Laboratory examination and sleep study were monitored to analyze the effects of OSA on biomarkers by LSD-t test,Mann-whitney U test,or Chi-square test.Correlation analysis was performed to analyze the association of OSA with high sensitivity C-reactive protein (hs-CRP) by Spearman correlation anaylsis.Results A cohort of 836 patients with ACS were enrolled including 408 patients in the normal-mild OSA group and 428 patients in the moderate-severe OSA group.The levels of leukocyte(x 109L) [7.78 (6.33,9.86) vs 7.29 (6.01,9.16),P=0.006],neutrophils(× 109L) [5.05 (3.84,7.23)vs 4.80 (3.74,6.66),P=0.044],monocytes(x 109L) [0.42 (0.33,0.54) vs 0.39 (0.31,0.51),P=0.033],hsCRP(mg/L) [3.18 (1.10,11.52) vs 1.78 (0.65,6.46),P＜0.01],fibrinogen(g/L) [3.17 (2.87,3.74) vs 2.97 (2.59,3.50),P=0.002],and uric acid(μmol/L) [360 (302,422) vs 341(283,407),P=0.006] in the moderatesevere OSA group were significant higher than those in the normal-mild OSA group.AHI (correlation coefficient=0.171,R2=0.020,P＜0.01),ODI (correlation coefficient =0.201,R2=0.027,P＜0.01),and TSaO2 ＜ 90％ (correlation coefficient =0.105,R2=0.005,P＜0.01) were positively correlated with hs-CRP;minimal SaO2 (correlation coefficient=-0.100,R2=0.001,P=0.008) and mean SaO2 (correlation coefficient =-0.127,R2=0.006,P＜0.01) were negatively correlated with hs-CRP.Conclusions For patients with ACS,the level of inflammatory markers in the moderate-severe OSA group is significantly higher than that in the normal-mild OSA group.Hs-CRP is significantly associated with the severity of OSA.Diagnosis and monitoring of OSA should be considered in ACS management in the future.

Objective: To explore the association between hypothyroidism and sleep breathing disorders in patients with coronary heart disease (CHD). Methods: A total of 784 patients with CHD were consecutively enrolled at the Emergency & Critical Care Center of Beijing Anzhen Hospital from June 2015 to May 2017. According to thyroid function test results, patients were divided into hypothyroidism group (79 cases) and non-hypothyroidism group (705 cases). All patients had undergone sleep monitoring. The sleep apnea status was compared between the two groups. Multivariate logistic regression and linear regression models were used to analyze the association between hypothyroidism and sleep breathing disorders in patients with CHD. Results: The proportion of females, mean body weight and body mass index in the hypothyroidism group were higher than those in the non-hypothyroidism group [26.6% vs.16.2%, (78.6±11.6) kg vs. (75.7±12.0) kg, (27.7±3.2) kg/m² vs. (26.6±3.5) kg/m², all P<0.05]. Patients in hypothyroidism group had a decreased average oxygen saturation (SaO₂) compared with patients in non-hypothyroidism group [ (93.2±2.9) % vs. (93.9±2.0) %, P=0.030]. In addition, events of hypoventilation in hypothyroidism group were significantly higher than those in non-hypothyroidism group[92.5 (45.8, 758.3) times vs. 68.0 (33.0, 125.0) times, P=0.013]. There were no significant differences in apnea hypopnea index, diagnosis of obstructive sleep apnea and other sleep breathing parameters between the two groups (P>0.05). A multiple linear regression analysis found that in patients with CHD, the correlation between hypothyroidism and average sleep SaO₂ was significant (β=-0.508, 95%CI -0.989--0.026, P=0.039). Conclusions: CHD patients with hypothyroidism had a lower sleep average SaO₂, and a higher sleep hypopnea events. There is a correlation between hypothyroidism and sleep hypoxia in patients with CHD. Clinical trial registration clinicalTrials.gov, NCT03362385.

Objective: To investigate the impact of moderate/severe obstructive sleep apnea (OSA) on the prognosis of acute myocardial infarction. Methods: We prospectively selected patients with acute myocardial infarction (AMI) who were hospitalized at the Emergency Critical Care Center of Beijing Anzhen Hospital from June 2015 to May 2017. Patients who met the inclusion criteria were examined with portable sleep respiration monitoring. Patients were divided into moderate/severe OSA group (apnea-hypopnea index (AHI)≥15 beats/hour) and no/mild OSA group (AHI<15 beats/hour) according to sleep AHI. The incidence of major adverse cerebrovascular events (MACCE) after discharge was compared between the two groups, and the independent risk factors of MACCE were analyzed. Results: A total of 432 patients were enrolled in this study, including 211 moderate/severe OSA patients (48.8%). Compared with no/mild OSA group,patients with moderate/severe OSA had higher body mass index ((27.17±3.22) kg/m² vs. (25.55±3.44) kg/m², t=-5.033,P<0.001), higher proportion of history of percutaneous coronary intervention (PCI) (18.5%(39/211) vs. 8.6%(19/221), χ²=9.076,P=0.003), and higher proportion of 3-vessel disease (31.3%(66/211) vs. 24.9%(55/221), χ²=10.196,P=0.017). The median follow-up time was 1.0 (0.7, 1.7) years. The incidence of MACCE in the moderate/severe OSA and no/mild group was 19.9%(42/211) and 11.3%(25/221), respectively. Kaplan-Meier analysis showed a higher cumulative risk of MACCE in patients with moderate/severe OSA (log-rank test,χ²=5.467, P=0.019). Multivariate Cox regression analysis showed that moderate/severe OSA (HR=1.915, 95%CI 1.016-3.611, P=0.045) and diabetes mellitus (HR=1.819, 95%CI 1.022-3.238, P=0.042) were independent risk factors for MACCE at 1 year post discharge in patients with AMI. Conclusions: Nearly half of AMI patients are complicated with moderate/severe OSA in this patient cohort. Coronary artery disease is more severe in AMI patients complicating with moderate/severe OSA. Moderate/severe OSA is an independent risk factor for MACCE at 1 year after discharge in patients with AMI. Whether the prognosis of AMI can be improved by intervention of OSA remains to be investigated. Trial Registration Clinical Trial.gov, NCT03362385.

The paper analyzes the conditions of research on the current scientific literature text feature extraction methods,applies the TF-IDF method based on background knowledge in the medical text feature extraction,and conducts experimental comparison in four medical fields.The result indicates that this method can obviously improve the extraction effect when there are few vocabularies to be extracted,and is obviously superior to the IDF based TF-IDF method in the aspects of filtration of commonly-used words in the text set and identification of important feature words.

The paper puts forward the method for evaluation on the scientific influence of institution based on PageRank algorithm,configures the initial weight of each institution based on the problems of dividing equally the webpage weight number in the classical PageRank algorithm and cited frequency of the application chapter,constructs the network matrix cited by institution through the citation situation of medical SCI papers published by partial colleges and universities in 2015,respectively calculates the PageRank values of institution when self-citation is excluded or included,and conducts comparative analysis on the sequence of cited frequency indicators of the institution as well as H index.This method can be used to evaluate scientific influence of institution from two dimensions of quality and quantity.

Multidimensional features ( life cycle features, universal acceptability, authority, innovation and inter-disciplinarity) of frontier knowledge and their measurement methods were determined according to the current scien-tific achievements in order to help scientific workers and decision makers timely discover and accurately recognize frontier knowledge.The framework for studies on frontier knowledge discovery in medical field was proposed with its key problems explained in order to provide reference for its future study.

Objective To investigate the relationship among Helicobacter pylori(H.pylori),CD4 positive cells and CD8 positive cells in gastric mucosa of the AIDS patients with gastritis.Methods Fiftyeight AIDS patients with upper abdominal pain were diagnosed with chronic gastritis through gastroscopy.The gastric biopsies from them were used for H.pylori detection with rapid urease test and Giemsa staining,pathology examination with HE staining,and immunohistochemistry analysis for CD4,CD8 positive cells in Gastric mucosa.And the application of flow cytometry was for the detection of peripheral blood CD4 and CD8 lymphocytes from the patients.Results H.pylori was positive in 26 cases,and negative was in 32 cases.CD8 cell expression in gastric mucosa of the AIDS patients with H.pylori positive was significantly higher than H.pylori negative patients(P＜0.05).There is no difference CD4 cell expression in gastric mucosa between the AIDS patients with H.pylori positive and H.pylori negative patients.Moreover,CD8 positive lymphocytes in gastric mucosa of those patients with H.pyloriinfection were significantly stronger than the CD4 positive lymphocytes.However,the peripheral blood CD4 lymphocytes from the patients with H.pylori infection were more than those from H.pylorinegative patients significantly(P＜0.05).Conclusion The expression level of CD8 cells in gastric mucosal tissues of AIDS patients with H.pylori infection were higher than those without H.pylori infection.The CD4 lymphocytes from the peripheral blood of the patients with H.pylori infection were more than those without H.pylori negative patients.