Objective To explore the value of T wave alternans (TWA) in prediction ventricular arrhythmias in post-op TOF children. Methods The characteristics of TWA were retrospectively analyzed in 36 post-op TOF patients and 120 age-matched normal children. The relationship of sustained TWA and ventricular arrhythmias was also analysed. Results Compared with normal children, the incidence of sustained TWA was significantly increased in post-op TOF group (χ2=6.98, P<0.05). In post-op TOF patients, the incidence of ventricular arrhythmia was much higher when sustained TWA was present (χ2=10.41, P<0.05). Conclusions There exists electrophysiological basis for ventricular arrhythmia in post-op TOF children. Sustained TWA has important value in prediction of ventricular arrhythmia of post-op TOF.

Objective To study the MR imaging features of intracranial subependymomas and to improve the knowledge more about it. Methods The imaging features of intracranial subependymomas in 17 cases proved pathologically were retrospectively analyzed, among which 11 cases were male and 6 cases were female, 16 cases had MR images and 1 case only had CT images.Results MR appearances of intracranial subependymomas were as follows :16 cases were all hyperintense relative to the normal grey matter on T2-weighted images and hypointense or isointense on T1-weighted images. 12 cases showed no enhancement or minimal enhancement after Gd-DTPA administration . 9 of 16 cases were located in lateral ventricle, 2 were in septum pellucidum, and the rest 5 were in fourth ventricle ,third ventricle ,prepontine cistern, right CPA and chiasmatic cistern respectively. In one case , CT showed isodensity and was enhanced in CE-CT,the lesion was situated in fourth ventricle. In all 17 cases, 11 were accompanied with microcystic structures. Conclusion Intracranial subependymomas are best delineated by MR imaging. The diagnosis of intracranial subependymomas should be considered when above findings are confronted.

Objective: To evaluate the preventive effect of ephedrine on hypotension under spinal anesthesia in patients with different age. Methods: Sixty patients scheduled for spinal anesthesia were randomly allocated to four groups with 15 each. Group Ⅰ and Ⅱ were adult patients aged from 25 to 55 years old and group Ⅲ and Ⅳ were geratic aged patients of 6575 years old. Every patient received a fluid loading of 7ml/kg before spinal anesthesia. The ephedrine was administrated to group Ⅱ and IV patients in a dose of 10mg i v and 30 mg i m and same amount of normal saline was administrated to group Ⅰ and Ⅲ as soon as spinal anesthesia was performed. Results:Thirty patients in the placebo groups developed a maximal decrease in MAP exceeding 20%. Ten of these (2 in group Ⅰ and 8 in group Ⅲ ) developed a decrease in MAP exceeding 35% and required treatment. In aged groups, all patients in group Ⅲ had a decrease in MAP exceeding 20 %, 53 % of whom, the decrease exceeded 35 %. Conclusion:Prophylactic use of ephedrine is effective in the prevention of hypotension during spinal anesthesia, especially in aged patients.

The development of liver surgery can be divided into several stages, including wedge liver resection, regular segmental liver resection and anatomical liver resection. With the development of biomedical sciences and information technology, liver surgery has developed into precise hepatectomy. The goals of precise hepatectomy are minimal invasion, maximal liver protection and best rehabilitation, This is mainly achieved through accurate preoperative evaluation, precise surgical planning, sophisticated surgical procedure and postoperative management. Its application significantly improves prognosis and quality of life of patients. This paper summarizes the concept and surgical technique of precise liver resection.

Objective:To research the expression of HBsAg DNA vaccine in immunized mice.Methods:The expression of HBsAg DNA vaccine was detected by immunohistochemistry staining in muscle fibers,lymphoid nodes and spleens of mice after intramuscular injection.Anti-HBsAg antibody was assayed by ELISA and the proliferation of spleen cells was measured by MTT.Results:The positive expression was observed in the tissues mentioned above.The titer of serum antibody showed positive results.Spleen cells could be proliferated by stimulating with HBsAg or ConA.Conclusion:The positive expression and certain kinds of immune responses have been shown in immunized mice.

The controlling system of triple pulse vacuum sterilizer for dental use adopts PIC single-chip computer as the controller. The information related to stream temperature and pressure of the stream and liquid mixture in the hermetic vessel is acquired and controlled. Linearization measurements of the temperature and pressure and fuzzy control technology are all involved in. The experiment result shows that the controlling system makes the sterilizer free from overshoot, steady-state error and non-robustness.

Objective To evaluate the long-term results of Chiari osteotomy in the treatment of Legg-Calv?-Perthes disease for the patients of 8 years old or above and discuss the factors that influence the prognosis of this disease. Methods There were 116 hips of 103 patients of Perthes disease treated with Chiari osteotomy between June 1986 and December 2002. All patients were 8 years old or above. 72 hips of these cases acquired follow-up, the meaning follow-up duration was 97 months(range, 38-196 months). According to lateral pillar classification, 30 hips were classified as group B, 22 hips as B/C group, 20 hips as C group. There were 50 hips in male, 22 hips in female, 47 patients between 8 and 10 years old, 22 cases between 10 and 14 years old. X-ray showed 25 hips with subluxation of femoral head preoperatively. Results According to the revised Stulberg classification system: (1)31 hips had Stulberg classⅠ,Ⅱ outcome, in which B group accounted for 19 of 30 hips, the hips in group C had the worst results: of 20 hips, only 3 had a Stulberg class Ⅰ or Ⅱ outcome, the results for the hips in lateral B/C border group were intermediate between those groups B and C. 33 hips had Stulberg class Ⅲ, in which B group had 10 hips, B/C group had 11 hips, C group had 12 hips. 8 hips had Stulberg class Ⅳ or Ⅴ, B group had 1 hip, B/C group had 2 hips, C group had 5 hips. (2)All cases had a satisfied containment, no one had subluxation after Chiari osteotomy. (3)48% of male patients had a Stulberg class Ⅰor Ⅱ outcome, in contrast, only 23% of female had the comparable outcome. (4)55% of the group of 8 to 10 years old patients had a Stulberg class Ⅰ or Ⅱ outcome, in comparison with 17% from the group of 10 to 14 years old cases. Conclusion The patients older than 8 years at the onset of disease and in the lateral pillar B or C group should be treated with surgical containment, Chiari osteotomy can fulfill such task. The gender, the age of onset, especially the lateral pillar classification strongly correlate with the outcome of Perthes disease, and the latter can help us to evaluate the severity degree of the disease and the prognosis.

Objective To study the expression of lipopolysaccharide(LPS) receptor,CD14 in the liver tissue during acute biliary infection and its relation with production of cytokines.Methods Rat models of acute biliary infection were established by ligating the choledochus and injecting Escherichia coli O111∶B4 into the duct.The expressions of CD14 protein and mRNA in liver tissue,the plasma levels of endotoxin,TNF-? and IL-6,and phagocytosis activity of Kupffer cells(KCs) were assayed at 0,3,6,12 and 24 h after operation.Ultrastructural changes in KCs were observed by electron microscopy.Results With the course prolonging in acute biliary infection,the plasma endotoxin level was progressively increased,KCs were activated and the levels of TNF-? and IL-6 markedly were increased,while the CD14 expression obviously increased at mRNA and protein levels.Conclusion The CD14 expression is gradually increased in liver tissue during acute biliary infection.KCs are activated and releasing more and more cytokines.It might be one of the important mechanisms of that KCs improve inflammatory response during the infection.

Objective To investigate the protective effect and the possible mechanism of lipopolysaccharide(LPS) preconditioning on ischemia/reperfusion injury of rat graft liver.Methods Male Sprague-Dawley rats were divided into three groups(n=30 in each group): sham operation group(Sham group),orthotopic liver transplantation group(OLT group) and LPS preconditioning group(LPS group).Only dissecting hepatoduodenal ligament was perfomed in Sham group.On day one,0.1 mg/kg LPS and on day 2,3,4,5,0.5 mg/kg LPS for LPS rats and 0.5 ml PBS pathogen-free solution for OLT rats was injected through caudal vein before OLT was performed by two-cuff method in the two group rats on day 8.The levels of tumor necrosis factor-?(TNF-?),ALT, AST in inferior caval vein blood and the activities of NF-?B in hepatic tissue were detected at 0,60,180 min after dissecting hepatoduodenal ligament in Sham group and after portal vein reperfusion in OLT group and LPS group.The morphological changes of hepatic tissue were observed through light microscope and electron microscope at different time points.Results As compared with Sham group at the different time points respectively,the activities of NF-?B and the levels of TNF-? were higher in OLT group and LPS group(P