Objective:To examine the surface of mineral trioxide aggr eg ate (MTA) when treated in different conditions in vitro. Method: Root blocks were prepared. MTA and other three dental materials (Dycal, Dyr act and amalgam) were respectively filled into the root canals of prepared root blocks. The roots with the materials were maintained in distilled water or simul ated body fluid (SBF) at 37 ℃ for 5 days. Scanning electron microscopy(SEM) and X-ray energy dispersive spectroscopy(EDS) were employed to investigate the mor phological changes and chemical components. Results:There was pr ecipitate of simple crystal units or crystalline structure in the MTA specimens. EDS showed one or two peaks corresponding to calcium or calcium and phosphorus. Conclusions:Apatite may produce and grew by MTA on its surface.

Objective To investigate the relationship between the plasminogen activator inhibitor 1(PAI 1) promotor region gene polymorphism and cerebral stroke.Methods The genotype of 4G/5G allele polymorphism in the PAI 1 promotor region were determined by polymerase chain reaction from leukocytes of 60 normal controls and 96 patients with cerebral stroke. Their plasma PAI 1 activity was assayed by ELISA.Results The plasma PAI 1 activity level in CI group was significantly higher than the CH and the control group.The plasma PAI 1 activity level (homozygote 4G/4G genotype patients) in CI and CH group was the highest,5G/5G genotype was the lowest,heterozygous 4G/5G genotype was in the middle;the difference was remarkable between 4G homozygote genotype and the other two groups,there was no remarkable significance between 4G/5G and 5G/5G genotype.There was remarkable difference between 4G/4G homozygote genotype in CI group and the controls(P 0.05 ).There was remarkable difference between the plasma PAI 1 activity in female patients with CI 4G homozygote genotype patients and the male patients of the same genotype (P

Objective The feasibility of constructing endothelialized vascular graft by using cryopreserved HUVCs was studies. Methods Forty-two human umbilical cords were used in this study. HUVECs were isolated by means of filling umbilical veins with digestive enzyme solution. HUVECs were then cultured and observed. Endothelial cells were identified by von Willebrand factor immunofluorescence staining and scanning electron microscope examination. Endothelial cells were suspended in cryopreserving solution which contains 10% DMSO and 10% fetal bovine serum in M199 and cryopreserved in liquid nitrogen. Post-thawed cells and non-frozen cells proliferation was evaluated by measuring the metabolic activity of tetrazolium compound. The endothelial cell growth characteristics were determined by daily observation using phase contrast microscope. Post-thawed endothelial cells viability was determined by trypan blue staining test. Flow cytometry were applied to determine the apoptosis rate of post-thawed cells. Cryopreserved endothelial cells morphological examinations such as hematoxylin and eosins staining and scanning electron microscope examination were carried out in this study. After cell culture and amplification, cryopreserved HUVCs were seeded on the inner surface of Gore-Tex graft to construct tissue engineered vascular graft. Results Extreme high-purified endothelial cells could be isolated by infusing digestive solutions to the lumen of human umbilical veins. Compared with non-frozen endothelial cells, Post-thawed endothelial cells showed 95% of vitality. Post-thawed HUVEC growth curve was similar to non-frozen ones'. Post-thawed HUVEC apoptosis rate (5.85? 0.56) % was higher than non-frozen ones (5.34?0.49)%; however, the difference was not statistically different. Endothelialization of vascular graft was carried out successfully. Cryopreserved cells on Gore-Tex surface showed a good growth trend. Conclusion Cryopreserved HUVCs may be taken as a cell choice for tissue engineering. Enough high pure endothelial cells could be isolated by digestive solutions infusion of human umbilical veins. Post-thawed endothelial cells are proved to have high vitality and growth potential on Gore-Tex surface in vitro.

Objective:To investigate the relationship between the plasminogen activator inhibitor 1(PAI 1) gene polymorphism and cerebrovascular disease and whether it played an important role in the pathogenesis of cerebrovascular disease Methods:The 4G/5G allele polymorphism in the PAI 1 gene promotor region were genotyped by polymerase chain reaction (PCR) from peripheral blood leukocytes from 60 normal controls, 65 patients with acute cerebral infarction and 31 hypertensives complicated with cerebral hemorrhage Their plasma PAI 1 activity were assayed by ELISA Results: The plasma PAI 1 activity level in the CI group was significantly higher than those in the other two groups PAI 1 level was significantly higher in 4G allele homozygous than both those in 4G/5G heterozygous and 5G homozygous Although PAI 1 level was higher in 4G/5G heterozygous than that in 5G homozygous, the difference had not reach statistically significant There were significant differences between acute cerebral infarction PAI 1 gene polymorphism and controls (P0 05), and PAI 1 levels of the 4G/4G genotype among female patients with CI were higher than those of the male patients with CI of the same genotype Conclusion: The results suggest that PAI 1 gene polymorphism may be a susceptible factor to acute cerebral infarction in Chinese, and 4G allele homozygous genotype may be the major risk factor of acute cerebral infarction, especially it may be an independent risk factor of female CI patients

Objective Evaluation of the benefit and safety of combined thrombolysis and precutaneous coronary intervention in acute myocardial infarction by retrospective analysis. Methods Precutaneous coronary intervention were performed in 45 patients with acute myocardial infarction immediately after thrombolysis. The clinical and angiographic data were compared with that of 31 patients with thrombolysis alone and 74 patients with primary precutaneous coronary intervention in the same period. Results Angiographic data showed that patients with PCI plus thrombolysis had more frequency of TIMI 3 flow than patients with thrombolysis alone (88.9% vs. 74.2%, P=0.087). Patients with PCI plus thrombolysis and with primary PCI had similar frequency of TIMI 3 flow (88.9% vs. 91.9% P=0.404). Clinical data showed that patients with PCI plus thrombolysis had less major adverse cardiovascular events in hospital than patients with thrombolysis alone (4.4% vs. 12.9%, P=0.181). Patients with PCI plus thrombolysis and with primary PCI had similar major adverse cardiovascular events (4.4% vs. 1.4%, P=0.319). Patients with three strategies of treatment had similar mortality (4.4% vs. 6.5% vs. 4.1%). Patients with three strategies of treatment had similar major bleeding events (4.4% vs. 3.2% vs. 1.4%) in hospital. Conclusion Combined thrombolysis and precutaneous coronary intervention maybe surpass thrombolysis alone, at least similar to primary PCI. This strategy of treatment is safe.

Objective To evaluate the role of video-assisted thoracoscopic surgery (VATS) in the diagnosis and treatment of esophageal tuberculosis. Methods We had conducted video-assisted thoracoscopic surgery and acute pathological examinations for diagnosing and treating esophageal tuberculosis in 8 patients from June 1996 to April 2004. Results All the 8 patents were clarified as having secondary esophageal tuberculosis (Six of them had been misdiagnosed as having esophageal tumors preoperatively). A lymphoidectomy was carried out in 5 patents and a focus debridement, in 3 patents. The duration of procedure was 30~50 min (mean, 45 min). The intraoperative blood loss was 50~100 ml (mean, 80 ml). Postoperatively, pleural effusion occurred in 2 patients and wound infection took place in 1. Follow-up for 5~27 months (mean, 15 months) in 7 patients revealed a remarkable relief of dysphagia and no recurrence. Conclusions VATS in combination with acute pathological examinations is a rapid, safe, accurate and minimally invasive alternative for the diagnosis and treatment of esophageal tuberculosis.

Objective To investigate the relationship between the expressions of glucose transporter protein-1 ,vascular endothelial growth factor in pancreatic cancer and the clinical indicators.Methods Im-munohistochemical staining was done in glucose transporter protein-1,vascular endothelial growth factor in pancreatic cancer and normal pancreas tissues.Results Glucose transporter protein-1,vascular endothelial growth factor of pancreatic cancer were expressed higher than that in normal tissue.The difference was statistically significant(P < 0.05).VEGF expression was related with lymph node metastasis,not with tumor grade,clinical stage(P<0.05).Glut-1 expression was related with tumor size,clinical stage and lymph node metastasis,not with pathological grading(P< 0.05).Conclusions Glucose transporter protein-1 ,vascular endothelial growth factor in pancreatic cancer are highly expressed .Both of them may participate in occurrence and development in pancreatic cancer.

Objective To improve the method of abdominal transplantation of hepatocytes. Methods The rat hepatic cells were embedded in collagen gel and cultured in vitro. The total protein (TP) and BUN levels in the nutrient solution were measured. The mixture of collagen nutrient solution and the hepatocytes was injected into abdominal cavity of rat recipients and then turned to gel there, so the hepatocytes were embedded in the gel. The hepatocytes in the abdominal cavity were rinsed out by the nutrient solution containing collagenase and were cultured in vitro in the nutrient solution without glucose (Glu). The Glu levels in the nutrient solution were measured. The control groups underwent the same process as the experimental groups except collagen. Results The TP, BUN and Glu levels in the experimental groups (hepatocytes embedded in collagen gel) were significantly higher than those in the control groups ( P

Objective To investigate the efficacy of ambroxol combined with penehyclidine hydrochloride for prevention of pulmonary complications after surgery due to acute abdomen in pediatric patients with upper respiratory tract infection.Methods Fifty pediatric patients with acute abdomen complicated with respiratory infection,of ASA physical status Ⅰ or Ⅱ,aged 6 months-5 yr,were randomly divided into test group (group A) and control group (group B),with 25 cases in each group.Immediately after admission to the operating room,ambroxol 1 mg/kg and penehyclidine hydrochloride 0.02 mg/kg were injected intravenously in group A,and atropine 0.02 mg/kg was given in group B.Extubation time and development of laryngospasm,bronchospasm and hypoxemia were recorded.The patients were followed up for 72 h after surgery and the development of postoperative pulmonary complications was recorded.Results Compared with group B,the incidence of hypoxemia and pulmonary complications was significantly decreased,and extubation time was shortened in group A.Conclusion Ambroxol combined with penehyclidine hydrochloride can prevent pulmonary complications after surgery due to acute abdomen and is helpful for prognosis in pediatric patients with upper respiratory tract infection.

Objective To explore the risk factors causing tetany in patients with hyperventilation syndrome. Meth?ods A total of 103 patients with hyperventilation syndrome treated in our hospital were included in this study. According to whether there was tetany, patients were divided into tetany group and non-tetany group. Values of gender, age, electrolyte, pH and p(CO2) were analysed between two groups. The factors of P<0.1 were engaged in binary Logistic regression. Logistic regression (Forward Wald) was used to analyze the risk factors of tetany in patients with hyperventilation syndrome. Re?sults In 103 patients there were 70 patients with tetany (68%), 33 patients without tetany(32%). The serum K+, serum phos?phorus and p(CO2) values were significantly lower in tetany group than those of non-tetany group (P<0.01), while the pH value was significantly higher in tetany group than those of non-tetany group (P<0.01). There were no significant differences in gen?der, age, serum Na+, serum Cl-, serum calcium (bound calcium and ionized calcium), ionized calcium and serum Mg2+levels be?tween two groups (P>0.05). It was revealed that the younger age, the lower level of the serum K+, serum phosphorus and p(CO2) were the risk factors of tetany through binary Logistic regression analysis. Conclusion The risk factors of tetany in patients with hyperventilation syndrome include younger age, lower level of serum K+and serum phosphorus and reduced p(CO2).