Based on the analysis of the influence of the valve pivot distance on the performance of mechanical heart valve (MHV), such as the valve opening and closing features, flow field characteristics and the valve assembly properties, value constraints of the valve pivot distance were established, and the reasonable valve was obtained by means of the finite element method. It can be shown that the central flow characteristics of the valve could be enhanced with the increasing of the ratio of pivot distance to valve inner diameter, but the plastic deformation of the ring could be liable to occur in the MHV assembly process. It is proved that the valve of specifications can be designed in similar ratio of pivot distance to valve inner diameter according to the result of the valve performance experiment.
Heart Valve Prosthesis ; Heart Valves ; Prosthesis Design

Objective To explore the clinical significance of the serum cell-free DNA on early diagnosis and prognostic value of patients with cervical carcinoma. Methods Forty-five patients with cervical carcinoma and 50 healthy women from May 2012 to February 2014 were selected from the Central Hospital of Ezhou. Serum cell-free DNA(cf-DNA),carbohydrate antigen125(CA125),carbohydrate antigen19-9(CA19-9), squamous cell carcinoma antigen( SCC ),β-human chorionic gonadotropin( β--HCG ) were detected by electrochemiluminescence analyzer. Results The levels of serum cf-DNA,SCC,β-HCG of patients in the cervical carcinoma group were(178. 8 ± 43. 4)μg/ L,(0. 7 ± 0. 3)μg/ L,(1. 3 ± 0. 4)kU/ L respectively, higher than those in health women((1 354. 7 ± 267. 2)μg/ L,(1. 4 ± 0. 4)μg/ L,(5. 2 ± 0. 6)kU/ L),and the differences were significant(t = 30. 690,9. 709,37. 614;P < 0. 001). Serum cf-DNA level of patients with Ⅱ-Ⅲperiod cervical carcinoma was(2 538. 8 ± 775. 3)μg/ L,higher than patients with Ⅰ period((1 244. 7 ± 253. 6)μg/ L;t = 8. 191,P < 0. 001). The area under the curve of ROC of serum cf-DNA,CA125,CA19-9, SCC,β-HCG were 0. 951 6,0. 638 2,0. 614 4,0. 805 7,0. 753 1 respectively and the AUC of serum cf-DNA was the largest. The sensibility,specificity,accuracy of cf-DNA were 75. 56% ,99. 13% ,93. 36% and 28. 32% , 93. 24% ,64. 26% in terms of CA125. Meanwhile,the sensibility,specificity,accuracy of CA19-9 were 19. 75% , 94. 47% ,67. 28% and 38. 87% ,88. 53% ,80. 16% in terms of SCC. The sensibility,specificity,accuracy of β-HCG were 43. 28% ,86. 21% ,77. 83% respectively. Conclusion Serum cf-DNA has high sensibility, specificity and accuracy in early diagnosis and prognostic value of patients with cervical carcinoma and it is worthy of clinical promotion.

Objective To study the applicability of ultrafiltration of tween-80 and it solubilizing schizonepeta volatile oil and paeonol of ultrafiltration. Method Taking components content as index, temperature, pressure, concentration and membrane pore size were selected as factors for orthogonal design method. The concentration was determinated in medical solution before and after ultrafiltration, and the transmittance rate (TS) was calculated to observe the content variation of tween-80 and it solubilizing solution. Results The four factors had markedly effect on TS of tween-80, concentration was statistically significant (P

Objective: To examine the causal relationships between obesity, peripheral blood lipid indicators and non-small cell lung cancer (NSCLC) using Mendelian randomization (MR) method, so as to provide the basis for developing NSCLC prevention and control strategies. Methods: Genetic variation data of three obesity evaluation indicators, including body mass index (BMI), body fat ratio (BFR) and waist-to-hip ratio (WHR), and seven peripheral blood lipid indicators, including triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C), apolipoprotein A1 (ApoA1), apolipoprotein B (ApoB) and lipoprotein a [LP (a)] were collected through genome-wide association studies (GWAS) and related public databases. Potential causal relationships between obesity, peripheral blood lipid indicators and NSCLC were analyzed using inverse-variance weighted (IVW) method and multivariable MR analysis upon a random effect model. Heterogeneity and horizontal pleiotropy of instrumental variables were evaluated using Cochran's Q test and MR-Egger regression. Results: There was statistically association between BMI with NSCLC (OR=1.256, 95%CI: 1.087-1.451); there were no statistically associations between BFR, WHR, seven peripheral blood lipid indicators and NSCLC (all P>0.005). There was heterogeneity in the association between BMI, BFR, WHR, TG, HDL-C and NSCLC (all P<0.05); no horizontal pleiotropy of instrumental variables was found (all P>0.05). There was no statistically association between BMI and NSCLC after adjusting BFR (OR=1.367, 95%CI: 0.878-2.128); there was still statistically association between BMI and NSCLC after adjusting WHR and peripheral blood lipid indicators (both P<0.05). Conclusions The increase of BMI is associated with the increased risk of NSCLC incidence. BFR may be a potential influencing factor for the association between BMI and NSCLC.

Background and purpose:Recently, it was reported that tanshinoneⅡA (TanⅡA) could inhibit proliferation, induce differentiation and apoptosis of human cancer cells. Previous studies also indicated that TanⅡA could inhibit the migration and invasion of osteosarcoma. However, the effects of TanⅡA on the migration and invasion of gastric cancer and the mechanism remains unclear. The aim of this study was to investigate the effect of TanⅡA on gastric cancer cell SGC7901 migration and invasion of in vitro. Methods:After different concentrations (0.5, 1, 2, and 4μg/mL) of TanⅡA treatment for 24, 48, and 72 h respectively, MTT assay were developed to detect the cell proliferation of SGC7901. The wound healing assay and 3D-transwell assay were used to observe the migration and invasion of SGC7901 cells, respectively. Expression of intercellular adhesion molecule 1 (ICAM-1), matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinase 2 (TIMP-2) mRNA and protein were measured with real-time PCR and Western blot. Results: 1, 2, and 4 μg/mL Tan ⅡA showed a dose-and time-dependent growth inhibition on SGC7901 cells. 2μg/mL TanⅡA showed a time-dependent migration inhibition of SGC7901 cells. 1, 2, and 4μg/mL TanⅡA could inhibit the invasion of SGC7901 cells. Real-time PCR and Western blot showed a reduction in expression of ICAM-1, MMP-2, and MMP-9, as well as an increase in expression of TIMP-2 (P<0.05).Conclusion:TanⅡA inhibits human gastric cancer SGC7901 cell migration and invasion in vitro. TIMP-2 upregulation and, ICAM-1, MMP-2, MMP-9 downregulation might be one of the mechanisms of anti-tumor of TanⅡA.

Objective To investigate the clinical effect of long-term home non-invasive assisted ventilation in stable chronic obstructive pulmonary disease (COPD) combined with type Ⅱ respiratory failure.Methods Seventy-eight patients with stable COPD combined with type Ⅱ respiratory failure were divided into treatment group (26 cases) and control group (52 cases).Patients in control group were given conventional treatment,including inhaled salmeterol/fluticasone plus long-term home oxygen therapy (LTOT).Patients in treatment group on the basis of conventional treatment were given non-invasive assisted ventilation therapy for 6-8 hours a day,and the course was 12 months.Blood gas analysis index [pH,arterial blood carbon dioxide partial pressure (PaCO2),arterial blood oxygen partial pressure (PaO2)],pulmonary function index [forced expiratory volume in 1 second (FEV1),FEV1 percentage of expected value (FEV1％)],6 min walk test (6-MWT) distance,St George's respiratory questionnaire (SGRQ) and acute episodes.Results After 12 months'follow-up,there was no endotracheal intubation and dead patients in treatment group.Five patients had acute trachea intubation and invasive mechanical ventilation,and 1 case died in the control group.The index of pulmonary function (FEV1,FEV1％) in two groups after treatment was improved compared with that before treatment (P＜ 0.05).But FEV1 and FEV1％ over the same period in treatment group after treatment was higher than that in control group (P ＜ 0.05).The blood gas analysis indicators (pH,PaCO2,PaO2) in treatment group after treatment were improved compared with that before treatment (P ＜0.05).PaO2 in control group after treatment was improved,compared with that before treatment (P＜ 0.05),but there was no significant difference in control group in pH and PaCO2 levels before and after treatment (P ＞0.05).After treatment 6-MWT distance,and SGRQ scores were improved,compared with that before treatment (P ＜ 0.05),6-MWT from the same period in treatment group after treatment was higher than that in control group,and SGRQ scores was lower than that in control group during this period (P ＜ 0.05).There was significant difference in average acute episodes between treatment group and control group [(0.84 ± 0.16) times vs.(1.49 ± 0.78) times,t =-3.65,P ＜ 0.05].Conclusion Home non-invasive assisted ventilation treatment can improve blood gas analysis and pulmonary function in patients of COPD combined with type Ⅱ respiratory failure of stationary phase,increase exercise tolerance,improve the quality of life,and reduce the number of acute episodes and intubation rate.

Objective To explore the protective effect of bone marrow mesenchymal stem cells (MSC) on diabetic myocardium and anoxic pre-conditioning (AP).Methods Eight-week-- old male Sprague-Dawley rats were given with a single intraperitoneal injection of streptozotocin (STZ) (60 mg/kg)to induce diabetes mellitus (DM).Donor rats were 8-week-old male Sprague - Dawley rats.Before transplantation,MSC were incubated in CM-DiI at a concentration of 2 μg/mL for 20 min.AP-MSC were exposed to 3 hours of anoxia.At 4 months after STZ injection,diabetic rats were randomly given with an intramyocardial injection of one of the followings:150 μL of Dulbecco's modified Eagle's medium ( DMEM),5 ×106 MSC/150 μL,or 5 × 106 AP - MSC/150 μL (n =10 for each group).Three months after STZ injection and 2 weeks after transplantation,we evaluated the cardiac function by echocardiography,and also evaluated the cardiac conditions by alkaline phosphatase staining,western blot analysis for apoptosis related proteins and signal pathways.Results MSC,especially AP- MSC increased fractional shortening (FS) of diabetic heart (P ＜0.01 vs DMEM respectively).AP-MSC greatly increased the capillary density of diabetic myocardium (P ＜0.01 vs DMEM and MSC group respectively).AP-MSC are anti-apoptotic in the rat DCM model,possibly mediated through cardiac upregulation of Bcl-2/Bax ratio ( P ＜ 0.05 ) and inhibiting the expression and activation of caspase - 3 ( P ＜ 0.01 ).Conclusions Intramyocardial transplantation of APMSC has a protective effect on diabetic cardiomyopathy.

Diagnosis, Differential ; Humans ; Hyponatremia ; diagnosis ; etiology ; therapy ; Inappropriate ADH Syndrome ; diagnosis ; etiology ; therapy

Objective To assess the efficacy of the prophylactic de-escalation use of noninvasive positive pressure ventilation(NPPV) in improvement of oxygenation following extubation after stanford type A aortic dissection.Methods 40 patients recovering from the stanford type A aortic dissection operation in the Center for Cardiac Intensive Care,Beijing Anzhen Hospital between December 2015 and April 2016,and meet the inclusion criterion after extubation,were investigated.The patients were random divided into 2 groups with RandA1.0 software,each group contained 20 patients:NPPV with mask vs.traditional oxygen treatment with mask.NPPV initial 2 h(started from extubation) settings:inspiratory pressure(IPAP) of 14-16 cmH2 O,expiratory pressure (EPAP) of 6-8 cmH2 O,the fraction of inspired oxygen (FiO2) of 0.35-0.55.2-8 h the parameters of setting were decreased:IPAP l0-12 cmH2 O,EPAP 4 cmH2 O.After 8 h the NPPV was finished and the oxygen treatment instead.The oxygen treatment settings:the flux inhalation of oxygen was 6-10 L/min,and FiO2 was adjusted to 0.35-0.55.Make a comparison with the two groups in the clinical effect at 2 h,8 h,24 h,3 days,and to compare their reintubation rate.Results PaO2 and PaO2/FiO2 were higher in the prophylactic NPPV group compared to oxygen treatment group after 2 h [94.7(89.7,100.1) mmHg vs.84.5(78.7,87.1) mmHg,P ＜0.05.(192.7 ±31.2) mmHg vs.(167.0 ± 18.9) mmHg,P＜0.05],8 h[99.1(90.3,132.8) mmHgvs.86.3(82.3,95.6) mmHg,P＜0.05.198.2(180.5,246.2) mmHg vs.172.5(164.7,191.2) mmHg,P ＜0.05],24 h[(100.0 ± 18.9) mmHg vs.(87.3 ±12.9) mmHg,P＜ 0.05.(197.5±36.8) mmHgvs.(170.1 ±29.8) mmHg,P＜0.05] and3 days[98.2(87.4,110.5)mmHg vs.86.8 (79.4,89.6) mmHg,P ＜ 0.05.(193.2 ± 37.1) mmHg vs.(164.4 ± 23.8) mmHg,P ＜ 0.05],and respiratory rate was lower in the NPPV group at the same time.Heart rate and mean arterial pressure were lower in the NPPV group at 24 h and 3 days.At 3 days in the NPPV group PaCO2 was lower,and left ventricular ejection fraction was improved.But the treatment of traditional oxygen leaded to a higher incidence of pulmonary atelectasis,and more longer hospitalization time.Conclusion In the early stage after extubation,prophylactic de-escalation therapy of NPPV for patients following operation of stanford type A aortic dissection,may quickly improve PaO2/FiO2,and increase the function of heart,avoid atelectasis.Furthermore,hospital stay was eventually shortened in NPPV group.

Objective To evaluate the clinical effect of vitrectomy for open globe injuries with intraocular foreign bodies in 48 hours after injury.Methods Retrospective analysis was used to evaluate the patients with open globe injuries (OGIs) accompanied by intraocular foreign bodies (IOFB) who underwent vitrectomy of pars plana vitrectomy (PPV) within 48 hours during the period from January 1,2009 to March 1,2015 in our hospital.Results Among the 56 eyes,16 eyes with intraocular foreign bodies occurred endophthalmitis,while the other 40 eyes did not;the intraocular foreign bodies removal rate was 100％.Among all the patient eyes,52 eyes were saved after surgery,while 4 eyes failed.The pars plana vitrectomy operation ratio of the intraocular foreign bodies patients with endophthalmitis and operated within 24 to 48 hours was 2.09 times than that within 24 hours.There was no significant difference in terms of eye preservation,one time of retinal reposition and abnormal intraocular pressure no matter the PPV surgery was conducted within 24 hours or 24 to 48 hours after injury.Conclusion Early vitrectomy is a safe and effective method for the treatment of open globe injuries with intraocular foreign bodies.