The segmentation of dental models is a crucial step in computer-aided diagnosis and treatment systems for oral healthcare. To address the issues of poor universality and under-segmentation in tooth segmentation techniques, an intelligent tooth segmentation method combining multiple seed region growth and boundary extension is proposed. This method utilized the distribution characteristics of negative curvature meshes in teeth to obtain new seed points and effectively adapted to the structural differences between the top and sides of teeth through differential region growth. Additionally, the boundaries of the initial segmentation were extended based on geometric features, which was effectively compensated for under-segmentation issues in region growth. Ablation experiments and comparative experiments with current state-of-the-art algorithms demonstrated that the proposed method achieved better segmentation of crowded dental models and exhibited strong algorithm universality, thus possessing the capability to meet the practical segmentation needs in oral healthcare.
ObjectiveTo evaluate the effect of positive end-expiratory pressure (PEEP) on respiratory function and hemodynamics in acute lung injury (ALI) with intra-abdominal hypertension (IAH). MethodsSix pigs were anesthetized and received mechanical ventilation (MV). Volume controlled ventilation was set with tidal volumn(VT) of 8 mL/kg,respiratory rate(RR) of 16 bpm,inspired oxygen concentration (FiO2) of 0.40,and PEEP of 5 cm H2O. ALI was induced by repeated lung lavage with diluted hydrochloric acid (pH<2.5) until PaO2/FiO2 declined to 150 mm Hg or less to established ALI model. Intra-abdominal hypertension was induced by an nitrogen inflator to reach intra-abdominal pressure of 20 mm Hg. Respiratory parameters and hemodynamics were continuously recorded at different PEEP levels(5,10,15,and 20 cm H2O). Every level was maintained for one hour. ResultsPaO2/FiO2 in PEEP5,10,15 and 20 were 90±11,102±10,172±23 and 200±34 mm Hg respectively. PaO2/FiO2 in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). Chest wall compliance (Ccw) in PEEP5,15 and 20 were 26±3,76±15 and 85±14 mL/cm H2O respectively. Ccw in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in lung compliance (CL) in different PEEP levels (P>0.05). Plateau pressure(Pplat) in PEEP5,10,15 and 20 were 30±3,31±2,36±2 and 38±4 cm H2O respectively. Pplat in PEEP15 and 20 were significantly higher than those in PEEP5 and 10 (P<0.05). There was no significant difference in Pplat between PEEP15 and 20 (P>0.05). Heart rate (HR) in PEEP5,15 and 20 were 113±17,147±30,and 160±30 beat/min respectively. HR in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in HR between PEEP15 and 20 (P>0.05).Cardiac index (CI) in PEEP5 and 20 were 4.5±0.6 and 3.5±0.6 L·min-1·m-2 respectively. CI in PEEP20 was significantly lower than that in PEEP5 (P<0.05). There was no significant difference in CI in PEEP5,10 or 15(P>0.05). Central venous pressure(CVP) in PEEP5,15 and 20 were 12±2,17±2,and 18±3 mm Hg respectively. CVP in PEEP15 and 20 were significantly higher than those in PEEP5 (P<0.05). There was no significant difference in CVP between PEEP15 and 20 (P>0.05). There were no significant differences in MAP,SVRI,ITBVI,GEDI,PVPI,or EVLWI between different PEEP levels. ConclusionConcomitant ALI and IAH can induce great impairments in respiratory physiology. When PEEP is gradually increased,oxygenation and the respiratory function are improved without significant secondary hemodynamic disturbances.
Chronic kidney disease (CKD) and hypertension are very common chronic diseases. Active and standardized treatment of hypertension in patients with CKD can not only delay the progress of renal disease, but also reduce the risk of cardiovascular events. In recent years, although the guidelines for hypertension have put forward detailed suggestions for the management of hypertension in CKD patients, there are differences in the recommendation of blood pressure target value for CKD patients. Combined with the latest guidelines, this review interprets the blood pressure measurement methods, diagnostic criteria, antihypertensive targets and drug therapy in patients with CKD.
We had performed transjugular intrahepatic portosystemic stent shunt (TIPSS) in one hundred and three patients with advanced liver cirrhosis and portal hypertension from July,1993 to January, 1995. TIPSS was carried out successfully in ninty-eight out of 103 cases and the technical success rate was 95.2%. Acute variceal bleeding was immediatly controlled and portal pressure reduced by an average of 1.36±0.02 kPa after TIPSS. The disappearance of gastric cornoary and esophageal varices, the shrinkage of spleen and the reduction of ascite were observed . Three patients died of acute liver failure and one died of variceal redbleeding within 30 days of treatment. Mild encephalohthy was obserbed in 10 cases with TIPSS. At follow-up of 1～22 months, variceal rebleeding and ascite were observed in 6 patients and stenosis of shunt was evident is 12.5% of cases by the subsequent doppler sonography. According to this result, TIPSS is an effective method for the treatment of portal hypertension.
Objective To analyze the protective effects of heat-shock response on the retinae of the rats after retinal ischemic reperfusion injury.Method Twenty Wistar rats (20 eyes) were divided into 4 groups: intracameral perfusion group (group P), intracameral perfusion after quercetin injection group (group P+Q), intracameral perfusion after heat shock group (group P+H), and in tracameral perfusion after quercetin injection and heat shock group (group P+Q+H ). According to the standard program established by International Society for Clinical Visual Electrophysiology, we recorded the results of the dark-adapted electroretinogram (D-ERG ),oscillatory potentials (OPs),and light-adapted ERG (L-ERG) of the rats with intraocular hypertension after induced by heat shock response. The expressions of HSP 70 of the rats in all groups were observed by Western blotting.Results The expression of HSP 70 of the rats in group P+H was the highest in all groups, but the expressions of HSP70 in group P+Q and P+Q+H were inhibited significantly. The amplitudes of a and b wave of ERG and O2 wave of OPs decreased, and the delitescence of them were delayed significantly in rats after intracameral perfusion. The amplitude of b wave of D-ERG and O2 wave of OPs in group P+H were higher than which in group P. Zero hour after perfusion, the amplitudes of all waves in group P+H increased significantly (Plt;0.05). Twenty-four hours after perfusion, the retinal functional resumption of the rats in group P+H was better than which in group P. In group P+Q and P+Q+H, the delitescences of all waves of ERG and O2 wave of OPs were the longest and the amplitudes were the lowest, and some waves even disappeared.Conclusions The heat-shock response may improve the recovery ability of the retinal cells after injury of ischemic reperfusion.(Chin J Ocul Fundus Dis，2003，19：117-120)
ObjectiveTo observe the relationship of serum tumor necrosis factor α (TNF-α), interleukin 6 (IL-6), and C-reactive protein (CRP) with obstructive sleep apnea hypopnea syndrome (OSAHS) associated pulmonary hypertension (OSAHS-PH). MethodsFrom September 2013 to October 2014, 38 OSAHS patients, 32 OSAHS-PH patients and 35 healthy subjects were enrolled from the General Hospital of Ningxia Medical University. OSAHS was diagnosed by polysomnography. The pulmonary artery systolic pressure (PASP) was measured by echocardiograph, and the diagnose criteria for pulmonary hypertension was PASP≥40 mm Hg. Serum TNF-α, IL-6, CRP and endothelin 1 (ET-1) were detected by enzyme-linked immunosorbent assay. The correlation between TNF-α, IL-6, CRP, ET-1 and PASP was analyzed. ResultsThe serum levels of TNF-α, IL-6, CRP and ET-1 were remarkably different among three groups (F=55.34, 25.05, 23.85, 34.06 respectively; all P < 0.05). The levels of TNF-α, IL-6, CRP and ET-1 in the OSAHS group were higher than those in the healthy group, and lower than those in the OSAHS-PH group (all P < 0.05). The PASP was positively correlated with the levels of the four factors (r=0.755, 0.762, 0.747, 0.759 respectively; all P < 0.01). ConclusionThe levels of serum TNF-α, IL-6 and CRP are correlated with pulmonary hypertension and they may be involved in the process of OSAHS-PH.
Objective To study the neural mechanism of hypotension or shock state in acute cholangitis in severe type (ACST) and its value of clinical application. Methods A technique of blocking abdominal splanchnic nervi via right adipose capsule of kidney was carried out on 28 patients by injecting 1% lidocaine before urgent operation. Results After blocking the relevant nervi, hypotension or shock state in 23 patients were improved significantly (Ｐ＜0.05). The death rate was lower (14.3%) after having performed biliary decompressions with laparotomy. Conclusion Patients′ hypotension or shock state at the early phase of ACST is the result of neural reflex in which the splanchnic nervi is its afferent pathway. Blocking the relevant nervi before urgent operation, the valuable opportunity of emergency treatment can be obtainded and the complication and death rate are reduced significantly.
ObjectiveTo investigate the risk factors of postoperative portal vein thrombosis (PVT) after devascu-larization in patients with cirrhotic portal hypertension. MethodsThe clinical data of 40 patients with cirrhotic portal hypertension treated with splenectomy and gastric pericardial devascularization were retrospectively analyzed to investigate the related risk factors. ResultsA total of 12 of the 40 patients suffered from PVT (30.00%). The results of multivariate analysis showed that portal vein diameter, postoperative portal vein velocity, platelet count at 2 weeks postoperatively, and postoperative portal vein pressure were the factors influencing the incidence of PVT after devascularization. Patients with the greater portal vein diameter and platelet count at 2 weeks postoperatively, the lower postoperative portal vein velocity and postoperative portal vein pressure, had higher ratio of PVT (P < 0.05). ConclusionPortal vein diameter, portal vein blood flow velocity, platelet count, and postoperative portal vein pressure were the main risk factors for PVT after surgery in patients with cirrhotic portal hypertension.
OBJECTIVE The purpose of this study was to study the effect of splenopneumopexy for patients with portal hypertension in children. METHODS From March 1993 to April 1998, splenopneumopexy was performed on six children with portal hypertension. Doppler ultrasound and radionuclide were used to demonstrate the portopulmonary shunt after operation. RESULTS The bleeding from the esophageal varices was controlled and the esophageal varices were eliminated gradually. The symptoms pertaining to hypertension were disappeared. The patency of the shunt was maintained without the formation of thrombosis. No pulmonary complication was observed. CONCLUSION The results indicated that splenopneumopexy was a safe and effective procedure for patients with portal hypertension in children.
Objective To explore the effect of pulmonary arterial hypertension on the children with functional single ventricle in the early period after Fontan operation. Methods Forty-three children with pulmonary arterial hypertension after Fontan operation were enrolled in our department between January 2015 and December 2016. There were 24 males and 19 females at a median age of 4.3 years ranging from 2.5 to 4.8 years. The pulmonary arterial pressure was evaluated by cardiac catheterization. There were 23 children diagnosed without pulmonary hypertension (a non-PAH group) including 16 males and 7 females, while 20 patients were diagnosed with pulmonary hypertension (a PAH group) including 8 males and 12 females. Postoperative parameters related to outcomes were compared between the two groups. Results There was no death in the non-PAH group, but the mortality of children in the PAH group was 20.0% (4/20, χ2=5.34, P=0.02). The central venous pressure (t=–2.50, P=0.02), N-terminal prohormone of brain natriuretic peptide (NT-proBNP, Z=–3.50, P<0.01), peritoneal dialysis rate (χ2=5.40, P=0.02), incidence of arrhythmia (χ2=4.40, P=0.03) in the PAH group were significantly higher than those of the non-PAH group. The early postoperative utilization rate of pulmonary vascular targeting agents in the PAH group was significantly higher than that in the non-PAH group (χ2=6.30, P=0.04). Conclusion Pulmonary arterial hypertension is one of the most important factors which influence the early postoperative prognosis of children with functional single ventricle after Fontan operation.