Missing data represent a general problem in many scientific fields, especially in medical survival analysis. Dealing with censored data, interpolation method is one of important methods. However, most of the interpolation methods replace the censored data with the exact data, which will distort the real distribution of the censored data and reduce the probability of the real data falling into the interpolation data. In order to solve this problem, we in this paper propose a nonparametric method of estimating the survival function of right-censored and interval-censored data and compare its performance to SC (self-consistent) algorithm. Comparing to the average interpolation and the nearest neighbor interpolation method, the proposed method in this paper replaces the right-censored data with the interval-censored data, and greatly improves the probability of the real data falling into imputation interval. Then it bases on the empirical distribution theory to estimate the survival function of right-censored and interval-censored data. The results of numerical examples and a real breast cancer data set demonstrated that the proposed method had higher accuracy and better robustness for the different proportion of the censored data. This paper provides a good method to compare the clinical treatments performance with estimation of the survival data of the patients. This pro vides some help to the medical survival data analysis.
Algorithms ; Breast Neoplasms ; epidemiology ; Female ; Humans ; Probability ; Statistics, Nonparametric ; Survival Analysis

Objective To evaluate the indications,method and prognosis of emergent hepateetomy and tran-scatheter arterial embolization(TAE) for spontaneous rupture of primary liver carcinoma(PLC). Methods Clinical data of 85 cases with PLC were analyzed. Patients were divided into four groups: the group of delayed hepatectomy (group A,n=30);the group of emergent transcatheter arterial embolization (group B,n=22);the group of emer-gent hepatectomy (group C, n=18) and the group of medical treatment (group D, n=15). The hemostasis achieve-ment ratio, operative complications, perioperative morbidity, 1-year and 3-year survival rates among the four groups were compared. Results In group A and B, celiac urteriogram in 52 cases showed that extravasation of contrast media happened in 14 cases (26.9%). The hemostasis achievement ratio was 100% (30/30, 22/22, 18/18) in group A,B and C,respectively,which was remarkably higher than that in group D(40%,6/15) (P<0.05);The in-hospital fatality was 0% (0/30),3.8% (2/52) and 16.7% (3/18),which was lower than that of group D(80.0%, 12/15) (P<0.01). The 1-year survival rate was 76.7% and 3-year survival rate of group A was 53.3%, which was higher than that of group B (45.5 % and 31.8 %) and group C (44.4% and 33.3 %) (P<0.05). The cases in group D did not survive one year(P<0.01). Conclusions Emergent hepatectomy and transcatheter arterial emboli-zation are safe and feasible for spontaneous rupture of primary hepatocellular carcinoma. For those with resectable ca-ses,surgical resection is the first choice after transcatheter arterial embolization.

Objective To establish a rapid,sensitive and specific diagnostic test for detecting Neisse-ria gonorrhoea.Methods The major outer membrane proteins(P Ⅰ )in different gonococcal serogroups were obtained by isolation of outer membrane complex with CTB-ethanol precipitation,the outer membrane proteins were extracted with Z 3,14 and EDTA,and purified with DEAE-Sepharose CL-6B to obtain P Ⅰ .Hybridoma cell lines producing McAbs against P Ⅰ were established with lymphocyte hybridoma techniques.Results The molecular weight of P Ⅰ A and P Ⅰ B were determined with SDS-PAGE as35.2kDa and36.7kDa,respectively.Five hybridoma cell lines producing McAbs continuouslly and stably against P Ⅰ A and P Ⅰ B were obtained,in-cluding two hybridoma cell lines producing McAbs against P Ⅰ A and three hybridoma cell lines producing McAbs against P Ⅰ B.The titers of McAbs in the supernatants in the cultures and in abdominal ascites of BALB/c were from1:64to1:256and from1:4096to1:16384,respectively;and the specificity of the McAbs against P Ⅰ A and P Ⅰ B was so high that they easily reacted with N.gonorrhoeae but did not with other antigens such as N.meningitidis etc.Conclusion The purified P Ⅰ and the McAbs obtained in the study provide a basis to establish a rapid,sensitive and specific diagnostic test for detecting N.gonorrhoea.

Objective This study aimed to evaluate the safety and efficacy of video-assisted thoracoscopic bipolar radio-frequency ablation in the treatment of isolated paroxysmal atrial fibrillation.Methods From September 2010 to December 2016,Seventy-two consecutive patients with paroxysmal atrial fibrillation underwent video-assisted thoracoscopic bipolar radio-frequency ablation at Fuwai Hospital.There were 50 males and 22 females with an average age of(56.5 ± 10.5) years and duration of atrial fibrillation with (6.5 ± 4.8) years.45 patients had previous catheter ablation.The patients were followed up at postoperative 3 months,6 months,1 year and annually.Success of ablation was defined as sinus rhythm and no duration of ≥30 s for rapid atrial arrhythmias,including atrial fibrillation,atrial flutter or atrial tachycardia in 24 h Holter examination.Univariate and multivariate logistic regression models were used to analyze the risk factors for atrial fibrillation recurrence.Results One patient converted to sternotomy due to bleeding on operation.All patients were successfully discharged.69 patients completed follow-up,with an average follow-up of(28 ± 18)months(3-60 months).The overall success rate was 73.9％,and the success rate without antiarrhythmic drug was 62.3％.Subgroup analysis showed that the success rate was 80％ when left atrial anterior and posterior diameter(LAD) ≤40 mm,and 57.9％ when LAD ＞ 40 mm (P =0.035).Multivariate logistic regression analysis showed that LAD ＞40 mm was an independent risk factor for postoperative recurrence of atrial fibrillation.Conclusion Video-assisted thoracoscopic bipolar radiofrequency ablation is a safe and effective method for the treatment of paroxysmal atrial fibrillation,especially in patients with LAD≤40 mm.

Objective:To observe the change of retinal artery angle in eyes with idiopathic epiretinal membrane (ERM) and to analyze the relationship between retinal artery angle, ERM classification based on optical coherence tomography (OCT), and visual acuity.Methods:A retrospective cross-sectional clinical study. A total of 187 eyes in 187 patients diagnosed with monocular idiopathic ERM (IERM group) in Department of Ophthalmology of Zhejiang Provincial People's Hospital and the Affiliated Eye Hospital of Wenzhou Medical University at Hangzhou from November 2018 to January 2023 were included in the study. The contralateral healthy eyes were included as the control group. All patients underwent best corrected visual acuity (BCVA), fundus photography, spectral-domain OCT, OCT angiography (OCTA) and axial length (AL) measurement. BCVA examination was performed using the standard logarithmic visual acuity chart, which was converted to the logarithm of the minimum angle of resolution (logMAR) visual acuity. The foveal avascular zone (FAZ) area was measured by OCTA. The central macular thickness (CMT) was measured by spectral domain OCTaccording to the grading criteria of ectopic inner foveal layer (EIFL) was divided into stages 1 to 4 with 42, 45, 62, and 38 eyes, and the IERM group was subdivided into stage 1, stage 2, stage 3, and stage 4 groups accordingly. Image J was used to measure the retinal artery angle and the 1/2 retinal artery angle on fundus images. Multiple linear regression analysis was used to analyze the correlation between BCVA and artery angle, 1/2 artery Angle, CMT, FAZ area and AL.Results:Compared with the control group, eyes in IERM group had worse BCVA ( t=9.727), thicker CMT ( t=12.452), smaller FAZ area ( t=-14.329), smaller artery angle ( t=-9.165) and smaller 1/2 artery angle ( t=-9.549). The differences were statistically significant ( P<0.001). With the increase of IERM stage, the artery angle and 1/2 artery angle decreased significantly ( F=21.763, 12.515; P<0.001). There was no significant difference in artery angle and 1/2 artery angle between stage 1 group and stage 2 group, and 1/2 arterial angle between stage 2 group and stage 3 group ( P>0.05). There were significant differences in artery angle and 1/2 artery angle between the other groups ( P<0.05). There were significant differences in CMT and logMAR BCVA among different classification subgroups in IERM groups ( P<0.05). There was no significant difference in FAZ area between grade 3 group and grade 4 group ( P>0.05). There were significant differences in FAZ area between the other groups ( P<0.05). Correlation analysis showed that decreased artery angle ( P=0.013) and increased CMT ( P<0.001) were associated with decreased BCVA. Conclusions:Compared with healthy eyes, the artery angle decreases significantly with the increase of ERM stage. Decreased retinal artery angle is associated with decreased visual acuity in IERM eyes.