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 provides some help to the medical survival data analysis.
Objective To evaluate safety and long-term efficacy of fully covered self-expandable mental stent (FCSEMS) in treatment of biliary stricture after liver transplantation (LT). Methods From January 2010 to June 2018, the data of patients with the biliary stricture after the LT underwent the endoscopic retrograde cholangiagraphy (ERCP) at the First Hospital of Lanzhou University were collected retrospectively. The therapeutic effect of the FCSEMS was evaluated. Results A total of 21 patients with the biliary stricture after the LT were treated. The success rate of the stent placement was 100%. The FCSEMSs were used in 7 cases and the only multiple plastic stents (MPSs) were used in 14 cases. There were no significant differences in the gender, age, time of biliary stricture, frequency of ERCP, recurrence time of biliary stricture, cure time of biliary stricture, curative effect, recurrence of biliary stricture, and incidence of complications between the patients treated with the FCSEMS and the MPS (P>0.050), but the number of plastic stents in the patients treated with the FCSEMS was significantly less than that in the patients treated only with the plastic stents (P<0.050), while the duration of stent retention was longer than that in the patients treated only with the plastic stents (P<0.050). Six patients were cured, 1 was remitted, and 2 were relapsed by the FCSEMS. Eight were cured, 3 were remitted, 3 were ineffective, and 5 were relapsed by the MPS alone. Conclusions FCSEMS might be an safe effective alternative to plastic stent in treatment of biliary stricture after LT, resulting in a longer duration placement, less number of plastic stent use. It is necessary to further accumulate cases to validate cure rate and recurrence rate of biliary stricture.
Objective-To apply self-pulmonary tissue flap to reconstruct esophagus directly or with alloy stent in this research. Methods Twenty-four dogs were divided into two groups, middle bronchus was ligated to prepare pulmonaryflap and incised, a 4 to 6 cm long and 1/2 to 2/3 perimeter defect was made in esophageal wall. Esophagus defect was repaired only with pulmonary flap (experimental group) and with pulmonary flap having self-expanded stent inside (control group). The gross appearance, histological apearance and barium X-ray films were observed at 2,4,6,8,10 and 12 weeks after operation. Results Two dogs died of anatomotic leak in experimental group, three dogs died of anatomotic leak and two dogs died of perforation of ulcer in control group. The growth of esophagus epithelium was observed from periphery area to central area after 8 to 10 weeks of operation. In pulmonary flap mass fibrous tissue proliferated and fibroblasts were active, but no necrosis occurred. Barium X-ray ofregenerated esophagus showed that mild stenosis and weakened peristalisis were observed in the middle of resophagus replacement, and that no obstruction, leakage, and dilation above anastomotic stoma occurred. Conclusion Pulmonary tissue flap can well support the mucosa crawl in the defect of esophagus. It is necessary to find a more suitable and satisfied stent for repairing segmental defect.
ObjectiveTo investigate the application scope and effects of pancreatic duct stent in common pancreas diseases.MethodThe literatures on application of pancreatic duct stent in common pancreas diseases at domestic and foreign were reviewed.ResultsPancreatic duct stent had been used in acute and chronic pancreatitis and pancreatic tumor, which could the relieve symptoms, reduce the complications of pancreatitis, improve the prognosis, shorten the hospital stay, and reduce the hospitalization costs. Meanwhile it had also been used in pancreatic tumor surgery, palliative treatment, and brachytherapy that some achievements had been made.ConclusionAlthough application of pancreatic duct stent in some common pancreatic diseases is still controversial, effect is better and has some advantages with small trauma and low incidence of complications, which also provides a new treatment option for some common pancreatic diseases.
Objective To observe the effects of vitrectomy for persistent fetal vasculature (PFV).Methods The clinical data of 11 patients (14 eyes) with PFV, including posterior PFV (one eye) and combined PFV (13 eyes), were retrospectively analyzed. Vitrectomy was performed for all patients, lensectomy was performed for seven eyes, retinotomy was performed for five eyes, retinotomy and scleral buckling was performed for one eye. Intraoperative and postoperative complications were observed. The followup period ranged from eight to 74 months, with the mean of 44 months. The visual acuity （VA） and intraocular pressure before and after surgery were comparatively analyzed.Results There were no intraoperative complications in all the patients. The surgery was performed successfully in 12 eyes （86.0%） and failed in two eyes （14.0%）. The postoperative VA of five eyes (35.7%) increased, four eyes （28.6%） didnprime;t change and five eyes （35.7%） decreased. The postoperative intraocular pressure of two eyes （14.3%） increased,11 eyes （78.6%） didnprime;t change and one eye （7.1%） decreased. There was one eye with persistent hypotension and one eye with recurrent retinal detachment after surgery.Conclusion Vitrectomy can prevent complications and improve visual acuity in some PFV patients.
ObjectiveTo study the prevention and treatment of restenosis after the stent placement in the latest progress. MethodsThere were four methods including drug-eluting stents, intracavitary illuminate, drug therapy, and mesenchymal stem cells, which prevented or treatment restenosis after stent placement. ResultsAll the four methods could reduce the postoperative restenosis rate after interventional treatment. Many experimental study of prevention and treatment of restenosis had obvious effect, but clinical curative effect was not very satisfactory, because of a series of problems such as safety, animal models, experiment method, and so on. ConclusionThe multiple factors and links caused restenosis should be considered fully, and interrupting the links or factors as far as possible could control the occurrence or development effectively.
Objective To systematically evaluate the efficacy and safety of sirolimus-eluting stents (SES) versus bare-metal stents (BMS) in treating patients with ST-segment elevation myocardial infarction. Methods The databases such as PubMed (1960 to Mar. 2011), EMbase (1980 to Mar. 2011), the Cochrane Central Register of Controlled Trials (1989 to Mar. 2011), CBM (1979 to Mar. 2011), VIP (1989 to Mar. 2011) and CNKI (1979 to Mar. 2011) were searched to collect all the randomized controlled trials (RCTs) on SES versus BMS in patients with ST-segment elevation myocardial infarction. After the data extraction and methodological quality evaluation, meta-analysis was conducted with RevMan 4.2 software. Results A total of 7 RCTs were included. Among 2 555 patients involved, 1 282 were in the SES group, while the other 1273 were in the BMS group. The results of meta-analyses showed that SES was superior to BMS in the target-lesion revascularization (OR=0.27, 95%CI 0.16 to 0.45, Plt;0.000 01) and target-vessel revascularization (OR=0.33, 95%CI 0.24 to 0.46, Plt;0.000 01). In contrast, there were no differences between SES and BMS in death, stent thrombosis and recurrence of myocardial infarction. Conclusion With the one-year clinical outcomes, SES is more effective than BMS in reducing the rate of target-vessel revascularization and target-lesion revascularization.
ObjectiveTo explore the relationship between blood glucose variability index and persistent organ failure (POF) in acute pancreatitis (AP). MethodsWe prospectively included those patients who were diagnosed with AP with hyperglycemia and were hospitalized in the West China Center of Excellence for Pancreatitis of West China Hospital of Sichuan University from July 2019 to November 2021. The patients were given blood glucose monitoring at least 4 times a day for at least 3 consecutive days. The predictive value of blood glucose variability index for POF in patients with AP was analyzed. ResultsA total of 559 patients with AP were included, including 95 cases of POF. Comparing with those without POF, patients with AP complicated by POF had higher levels of admission glucose (11.0 mmol/L vs. 9.6 mmol/L), minimum blood glucose (6.8 mmol/L vs. 5.8 mmol/L), mean blood glucose (9.6 mmol/L vs. 8.7 mmol/L), and lower level of coefficient of variation of blood glucose (16.6 % vs. 19.0 %), P<0.05. Logistic regression analyses after adjustment for confounding factors showed that the risk of POF increased with the increase of admission glucose [OR=1.11, 95%CI (1.04, 1.19), P=0.002], minimum blood glucose [OR=1.28, 95%CI (1.10, 1.48), P=0.001] and mean blood glucose [OR=1.18, 95%CI (1.04, 1.33), P=0.010]; with the higher level of coefficient of variation of blood glucose [OR=0.95, 95%CI (0.92, 0.99), P=0.021], the risk of POF decreased. The results of area under the curve (AUC) of the receiver operator curves showed that AG [AUC=0.787, 95%CI (0.735, 0.840)] had the highest accuracy in predicting POF, with sensitivities of 60.0% and specificities of 84.7%. ConclusionHigh admission glucose, minimum blood glucose, mean blood glucose, and low coefficient of variation of blood glucose were risk factors for the development of POF in patients with hyperglycemic AP on admission.
ObjectiveTo evaluate the feasibility, safety and efficacy of endovascular treatment for chronic thoracoabdominal aortic dissection. MethodsThe patients with chronic thoracoabdominal aortic dissection who underwent total endovascular treatment at Shanghai City First People’s Hospital between December 2021 and March 2024 were retrospectively analyzed. The patients were divided into single-trunk group and double-trunk group according to the treatment methods. Clinical data including demographic characteristics, preoperative risk factors, surgical details, postoperative complications and long-term follow-up data were collected. Outcome measures mainly included surgical success rate, in-hospital mortality, endoleak rate and incidence of branch restenosis. ResultsThirty-four patients with thoracoabdominal aortic dissection were treat with total endovascular treatment. That success rate of operation was 100%. The in-hospital mortality was 2.94%. the incidence of paraplegia was 0.00%. the incidence of cerebral infarction was 2.94%. The incidence of type Ⅲ endoleak was 5.88%. The incidence of branch artery stenosis was 8.82%. The incidence of dissection progression was 8.82%. The reintervention rate was 14.71%. In the aspect of reconstruction of splanchnic artery branches, fenestration stent was the main method in the single-trunk group, and branch stent was the main method in the double-trunk group, the difference was statistically significant (P<0.05). There was no significant difference in perioperative and mid-term follow-up results between the two groups (P>0.05). ConclusionTotal endovascular treatment is a safe and effective treatment option for patients with thoracoabdominal aortic dissection.
Objective To summarize the experiences of single stage repair of persistent fifth aortic arch associated with stenosis and interrupted aortic arch and other cardiac anomalies,and to improve surgical effect of the diseases． Methods From Jan．2000 to May 2008，five patients with persistent fifth aortic arch were operated in this hospita1，the age at operation was 1.8-108.0 months and body weight 3.7-31.0 kg．Three patients had chronic heart failure and respiratory infection repeatedly.All patients received single stage repair. Results There were two early hospital deaths，one patient’s parents gave up all the therapy because of cardiac insufficiency, pulmonary hypertension crisis and severe pulmonary infection; another one died of severe pulmonary hypertension crisis，the low cardiac outflow and left heart failure. Three patients were followed up, followup time was 55.67±48.64 months. The results were excellent,and one patient had been followed up for 8 years,the latest magnetic resonance imaging showed that diameter of the enlarged fifth aortic arch was 9.3 mm. Conclusion Persistent fifth aortic arch operation can achieve good exposure,less incisional wound and excellent recovery through midline sternotomy.Because of systemic hypertension and the affection of associated anomalies the operation should be performed as early as possible.