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.

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

Objective To compare the values of 3D-SPACE sequence and 2D-TSE sequence for displaying the anatomical details of the sinus tarsi ligament of the ankle.Methods 1.5T Siemens Auanto MRI scanner and 8-channel skull phased array coil were used for the examination of 26 healthy volunteers with 3D-SPACE three-dimensional isotropic sectional scanning as well as 2D-T1WI-TSE transverse and 2D-T2WI-TSE coronal sagittal two-dimensional fast spin echo scan.Two senior MRI radiologists evaluated the display rates of the two sequences for the cervical ligament of sinus tarsi and talus ligament so as to determine the values of the two sequences for displaying the cervical ligament of sinus tarsi.Results 3D-SPACE sequence behaved significantly better than 2D sequence when used to display the sinus tarsi ligament (P＜0.05),and the display rates were statistically different at different positions (P＜0.05).3D-SPACE sequence gained obvious advantages over 2D conventional TSE sequence when used to display the cervical ligament of sinus tarsi and talus ligament,and the highest display rate occurred in case of the cervical ligament of sinus tarsi scanned with 3D-SPACE coronal view and in case of the talus ligament scanned at coronal and sagittal positions.Conclusion 3D-SPACE sequence can display clearly the anatomical details of the sinus tarsi ligament with multiplanar reconstruction,curved planar reformation and etc,and thus is worthy promoting clinically.

Objective To investigate the influence of different timing of surgery on patients with poor-grade intracranial aneurysm. Methods The clinical data of 86 patients with aneurysmal subarachnoid hemorrhage (Hunt-Hess gradeⅣ toⅤ)were analyzed retrospectively. The patients were divided into an ultra-early treatment group (the operative time within 24 h after onset;n=40),an early treatment group, (24 to 72 h after onset;n=27),and middle and late treatment group (>72 h after onset;n=19)according to the different timing of surgery. The prognosis of patients at 6 months after procedure was evaluated with the modified Rankin Scale (mRS)scores. The differences of the rate of good prognosis (mRS 0 to 2)and mortality in patients of the 3 groups were compared. Results (1 )The ratios of good prognosis in the ultra-early treatment group,early treatment group,and middle and late treatment group were 55. 0%(n=22),33. 3%(n=9),and 21. 1%(n=4),respectively. There were significant differences (P<0. 05). The mortality rate of the ultra-early treatment group (7. 5%)was lower than that of the early treatment group (25. 9%) or middle and late treatment group (42. 1%). There were significant differences (P<0. 05). (2)There were significant differences in the rate of good prognosis in different timing of surgery in patients with gradeⅣ(P<0. 05);there was no significant difference in the rate of good prognosis in patients with grade Ⅴ(P>0. 05). The mortality ratios in patients of the 3 groups were 2/18,4/11,and 6/11,respectively. There were significant differences (P<0. 05). Conclusion Ultra-early operation may benefit part of the patients with poor-grade aneurysm,particularly in patients with gradeⅣ. As for the patients with grade Ⅴ, ultra-early operation may help to reduce short-term mortality rate,however,the rate of vegetative state is high.

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.

Objective To investigate the regularity and significance of serum interleukin-6(IL-6) levels in the patients with sepsis.Methods Forty sepsis patients with APACHEⅡ scores over 12 and 30 normal controls were involved in the study.The IL-6 levels in serum were detected with radio-immunity analysis assay and the correlations among the IL-6 levels,the prognosis and APACHEⅡ score were investigated.Results In the patients with sepsis,the average level of IL-6 in serum was(152.02?55.77) pg/ml,which was significantly higher than that of the control group [(85.79?30.96) pg/ml](P