BACKGROUND:A large number of studies have shown that cast metal post-core has many advantages that it is close to the canal wal has high strength and can shape the core outside the root according to the needs. The cast metal post-core also has good retention, resistance and wel effect on clinical repair of dental defects. OBJECTIVE: To observe the clinical effect of Co-Cr aloy cast post-core and porcelain fused metal combined crowns in restoration of the separated mandibular molar residual crowns and roots. METHODS:Totaly 28 patients (42 teeth) who had the separated mandibular molar residual crowns and roots were enroled, including 10 males and 18 females, aged 18-32 years. After perfect root canal therapy and part of teeth with crown lengthening, teeth were repaired with Co-Cr aloy cast post-core and porcelain fused metal combined crowns. The patients were folowed up for 2 years. The repair effect was evaluated by combining clinical manifestations with X-ray examination. RESULTS AND CONCLUSION: During 2 years of folow-up, 26 cases were repaired successfuly, 2 cases failed, including 1 case of periapical periodontitis and 1 case of periodontitis. These results demonstrate that the cast post-core and porcelain-fused-metal combined crown has a good result on the residual root and crown of the separated mandibular molar.

ObjectiveTo explore the effect of endoscopic sinus surgery combined with mitomycin in nasal inverted papilloma (NIP). MethodThe clinical data of 75 patients with NIP was retrospectively analyzed and divided into treatment group (endoscopic sinus surgery combined with mitomycin treatment, 38 cases) and control group (endoscopic sinus surgery treatment, 37 cases) by random digits table. Results There was no complication in treatment group, the symptoms disappeared after treatment, good recovery and surgery epithelization was found after follow-up, 1 case of grade Ⅲ recurred at 3 months after treatment and followed up for 5 years without recurrence. In control group, 37 cases of conventional dressing endoscopic treatment, recurrence within 1 year in 3 cases, 4 cases of recurrence in the second year, 5 cases of reoperation cured, 2 cases of malignant transformation. The efficacy was no statistically significant between two groups( X2 =9.86,P ＜ 0.05). ConclusionEndoscopic sinus surgery combined with mitomycin in treatment of NIP, intraoperative and postoperative adjuvant therapy given to the local mitomycin, inhibit their growth and development, can inhibit the NIP recurrence and improve the cure rate.

Objective To explore pre-service training model and its efficacy for medical undergraduate interns.Methods Anonymous questionnaire survey was conducted for 50 medical undergraduates by teaching management staff.Results Totally 62％ students thought that pre-practice training was necessary,62％ students commented that the arrangement of this pre-practice training was reasonable and feasible,more than 95％ students supported the content and form of this training and more than 95％ students believed that pre-practice training can culture the sense of organizational discipline,foster favorable doctor-patient relationship and promote clinical knowledge and skill acquisition.In general,medical undergraduates had high degree of recognition after systematic training.Conclusion A set of standardized pre-practice training programs should be summarized and constantly be refined and improved so as to ensure the training quality.

Objective To study the DNA damage in hippocampal cells of rats induced by 1 800 MHz electromagnetic irradiation. Methods Wistar rats were randomly divided into four groups, 2 exposed groups and 2 controls. The experimental subjects were exposed to the 1 800 MHz (continuous wave, CW) electromagnetic fields for 21days (12 h/d), the power densities were 0.5 mW/cm2 and 1.0 mW/cm2, meanwhile, sham-control exposures were carried out, the DNA damage was examined by Comet assay. Results The tailed rate and the tail area of the hippocampal cells in 1.0 mW/cm2 group was higher or larger than those in the control and 0.5 mW/cm2 groups(P

Objective To investigate the effects of different doses of remifentanil on the renal ischemiareperfusion (I/R) injury in rats. Methods Sixty male SD rats weighing 220-250 g were randomly divided into 5 groups ( n = 12 each): sham operation group (group S), model group (group M), low, median and high doses of remifentanil groups (RL, RM and RH groups). The rats were anesthetized with intraperitoneal 5% chloral hydrate 6 ml/kg. Renal ischemia was induced by clamping the bilateral renal arteries for 45 min using an atraumatwere infused via the caudal vein 15 min before ischemia respectively and the infusion was stopped at 30 min of reperfusion, while S and M groups received equal volume of normal saline instead. Blood samples were collected from the femoral vein at 30 min and 24 h of reperfusion for measurement of serum creatinine (Cr) and blood urea nitrogen (BUN) concentrations. The rats were sacrificed at 24 h of reperfusion and the renal tissues were removed for determination of MDA content, SOD and Ca2+ -ATPase activities. Pathological changes in renal tissues were observed with light and electron microscopes. Results Compared with group S, the concentrations of serum Cr and BUN and content of MDA were significantly increased, while activities of SOD and Ca2+ -ATPase were significantly decreased in the other 4 groups ( P ＜ 0.05 or 0.01). Compared with group M, the concentrations of serum Cr and BUN and content of MDA were significantly decreased, activities of SOD and Ca2+ -ATPase were significantly increased (P ＜0.05 or 0.01) and the pathological changes were reduced in RH, RM and RL groups. The plasma BUN and Cr concentrations and MDA content were decreased gradually and SOD and Ca2+ -ATPase activities were increased gradually with the increase in the doses of remifentanil in RL, RM and RH groups ( P ＜ 0.05 or 0.01 ).Remifentanil infusion significantly attenuated the pathologic changes in a dose-dependent manner. Conclusion Remifentanil can reduce the renal I/R injury in a dose-dependent manner by inhibiting lipid peroxidation and increasing Ca2+ -ATPase activity.

Forty-eight cases of the third lumbar transverse process syndrome were treated by Ashi point functional exercises. The results showed that cure occurred in 22 cases, marked effectiveness in 16 cases,effectiveness in 10 cases and the total effective rate was 100%.

Objective: Using the property of (?-estrogen receptor, Fas/?-estrogen receptor fusion gene was constructed which can lead to hormone-induced apoptosis after transfected into glioma cells. Methods: The transmembrane domain, cytoplasmic domain of human Fas gene was fused with the HBD gene fragment of human (?-estrogen receptor by PCR and gene recombination techniques, and was then inserted into eukaryotic vector pcDNA3. Human glioma cells BT325 were transfected with the recombinant plasmid by lipofectamine-rnediated gene transfection. Results: After selection with C418 (or six weeks, transformants expressing the fusion gene were selected out and identified by Western blot. MTT detection showed that (?-estradiol had cytoxic effect on the transformants with IC_(50) of about 10~(-9) mol/L. DNA Ladder detection showed that the transformants could be effectively induced to apoptosis. Conclusion: Fas/?-estrogen receptor fusion gene transfected glioma cells can be induced to apoptosis in a tight estrogen indepent manner.

Objective:To obtain highly purified recombinant human IGF-Ⅰ(rhIGF-Ⅰ) and identify it.Methods:rhIGF-Ⅰ Was purified through ion-exchange chromatography and gel filtration chromatography after the inclusion bodies of rhIGF-Ⅰ were extracted from Escherichia coli. The recombinant protein was characterized through molecular weight assay, Western-blot, and fluorescent chromatography. The renaturation and biological assay of rhIGF-Ⅰ were investigated. Results and Conclusions: The purity of rhIGF-Ⅰ was higher than 99%. The analysis of molecular weight, Western-blot, fluorescent chromatography and sequences of NH2-terminal 15 amino acids were same as those anticipated. 3-10 mg/ml was the concentration of renatured rhIGF-Ⅰ to support half-maximal stimulation of cell proliferation with BALB/c 3T3 cells.

Objective To evaluate the detection rate of lesions of patients with Crohn’s Disease(CD)tusing combining the con-ventional MR and Cine MRE(MR enterography).Methods MRI images of twenty-nine patients with CD confirmed by clinic were analyzed retrospectively.Scan sequences include coronal Cine MRE,and standard MR protocol (FIESTA,SS-FSE,LAVA C+). Two radiologists analyzed the images with double blind method to explored whether there were significant differences existing be-tween having or having not Cine MRE on lesion detection rate (wall thickness,stenosis,comb sign,adhesions,fistulas).Results The number of lesions detected by standard MR combined with Cine MRE compared with standard MR alone were 82/80 (P =0.1 6) for wall thickening,52/43 (P =0.03)for stenosis,6/7 (P =0.36)for the comb sign,5/7(P =0.66)for adhesions,2/2for fistulas re-spectivily.Conclusion It is meaningless to combine Cine MRE with standard MR in lesions detection in patients with CD,Cine ima-ges can accurately determine diseased bowel stenosis,and show the adhesive location.On the basis of standard MR,Cine MRE can be added in patients with CD when necessary.

Objective To clone and express the outer surface protein C ( OspC) from a Chinese Borrelia afzelli FP1 strain and to evaluate the immune protectivity of the recombinant OspC protein ( rOspC) . Methods The gene encoding OspC protein of Borrelia afzelli FP1 strain was amplified by polymerase chain reaction (PCR) and then inserted into pET-30a plasmid to construct the recombinant expression plasmid pET-30a-OspC. The transformed E. coli BL21 strains carrying pET-30a-OspC plasmid were induced by IPTG to express OspC protein. The expressed proteins were purified by Ni-IDA resin chromatography and analyzed by SDS-PAGE and Western blot assay. Indirect immunofluorescence assay ( IFA) was performed to detect anti-rOspC protein antibodies in serum samples from rabbits immunized with rOspC protein. In vitro neutral-ization test was performed for evaluation the immune protectivity of rOspC protein. Results The recombi-nant expression plasmid pET-30a-OspC was successfully constructed and highly expressed in E. coli BL21. A strong antigen-antibody reaction between the rOspC protein and polyclonal antibody against Borrelia afzelli FP1 strain was detected by Western blot assay. The titers of IgG in serum samples from rabbits immunized with rOspC protein were significantly elevated. The in vitro neutralization test indicated that 106/ml of Borre-lia afzelli FP1 strains were neutralized by every anti-OspC protein serum sample from the experiment group. Conclusion The rOspC protein showed a strong immune protectivity against Borrelia afzelli, which could be used in the development of polyvalent subunit vaccine against lyme disease.