This review discusses several strategies that have been employed to enhance the regenerative effectiveness of artificial nerve guidance channels. These strategies include the use of scaffolds, the integration of contact-mediated cues within the tubular construct, and incorporation or delivery of exogenous growth factors into the conduit lumen uniformly or in a gradient form. Animal and clinical studies are reviewed to explain some of the ideas involved in developing a guidance channel of the future.

Objective To set up the filter mating method of plasmid conjugation experiment for Corynebacterium.Methods The first plasmid conjugation between different genus was performed by filter method.Three strains of highly erythromycin-resistance Enterococcus faecalis isolates[minimal inhibitory concentration(MIC)of erythromycin>256 mg/L,MIC of levofloxacin≤8 mg/L] which screened by agar dilution method were used as donators and 3 strains of Corynebacteria isolates(MIC of erythromycin≤32mg/L,MIC of levofloxacin=128 mg/L)were used as acceptors.In the second conjugation between the same genus but in different species,three Corynebacterium xerosis strains(MIC of erythromycin>256 mg/L,MIC of ceftazidime=16 mg/L)which were conjugants of the first conjugation were used as donators and 6 strains of Corynebacteria isolates(MIC of erythromycin≤32 mg/L,MIC of ceftazidime 128 mg/L)were used as acceptors.Results In the first conjugation between different genus,the plasimid conjugations were done for 9 times between 3 donators and 3 acceptors,4 of which gained the phenotype and genotype of resistance and the transfer rate was 44%.In the second conjugation experiment,the plasmid conjugations were done for 18 times between 3 donators and 6 acceptors,7 of which gained the resistant phenotype and the transfer rate was 39%.Erythromycin-resistance was transferred from the donators to the conjugants in varying degrees.The resistance was transferred from Enterococcus faecalis to Corynebacteria and then to other Corynebacteria which were of the salne genus but of different species.Conclusion Filter mating conjugation method could be used to study the mechanisms of resistance transmission of Corynebacterium.

Objective To analyze the characteristics and influencing factors of coronary sinus(CS) dilation in patients with primary pulmonary hypertension(PPH) and persistent left superior vena cava(LSVC). Methods Control group included twenty-two normal subjects [mean age ( 40.6 ? 10.6 ) years],PPH group included twenty-six patients with PPH [mean age ( 41.9 ? 11.4 ) years] and LSVC group included thirty-three patients with LSVC [mean age ( 30.9 ? 15.8 ) years]. After the standard apical four-chamber view was obtained,the transducer was tilted backward to direct ultrasonic beam towards the left atrioventricular groove,then the distal part of the CS could be exposed. Echocardiographic parameters of the CS included end-systolic diameter of CS orifice(CSOESD),end-diastolic diameter of CS orifice(CSOEDD),the ratio of CSOESD to CSOEDD (CSOESD/EDD). Results CSOESD,CSOEDD were larger [CSOESD ( 12.56 ? 3.58 )mm vs ( 8.47 ? 2.32 )mm,P

Objective To establish stable Graves disease (GD) mice models with immunization and electroporation (EP).Methods Fifty mice were divided into 3 groups by random number table method:experimental group (n =30),control group (n =10),blank group (n =10).Recombinant plasmid pcDNA3.1/hTSHR268 was constructed and injected to bilateral gastrocnemius in experimental group mice on the 1st,4th,7th and 10th week.The same volume of normal saline was injected in the control group and blank group at the same time.Both experimental group and control group were subjected to EP at the same time and the same location to enhance immunization.Serum T4 was tested with radioimmunoassay.TRAb N-terminal (TRAb N) and TRAb C-terminal (TRAb C) antibodies were tested with ELISA.Whole body 99TcmO4-imaging was performed and then thyroid morphology and pathology were investigated.Data were analyzed by one-way analysis of variance and the least significant difference (LSD) t test.Results GD BALB/c mice models were built successfully (80％,24/30).Serum T4 increased from (16.06±5.16) nmol/L at the basic level to(95.04±68.92) nmol/L on the 12th week(F=18.906,t=-5.598,P＜0.05).Serum TRAb N antibody increased from (0.006±0.002) U/L at the basic level to (0.251±0.110) U/L on the 12th week(F=47.491,t=-10.869,P＜0.05).Serum TRAb C antibody increased from (11.176±2.635)×103 arbitrary unit (AU)/L at the basic level to (46.395±22.001)× 103 AU/L on the 12th week(F=14.642,t =-7.787,P＜0.05).On the 18th week serum T4,TRAb N and TRAb C decreased to (36.64±23.68) nmol/L,(0.094±0.053) U/L and (24.456±6.725)× 103 AU/L respectively,which were still higher than those preimmune levels(t=-4.161,-8.085,-9.008,all P＜0.05).There were no significant change of T4,TRAb N and TRAb C in the control group and blank group.After 4 times of immunization,the 99TcmO4-uptake by thyroids in immunized mice increased.The thyroid glands of immunized mice showed enlargement.Microscope examination showed that there were lymphocytes infiltration,colloid decrease and epithelial cell proliferation in thyroids of immunized mice.Conclusion GD mice models were successfully established by injecting recombinant plasmid pcDNA3.1/hTSHR268 and EP.

Objective To study the influence of blood glucose, blood lipids and other cerebral infarction risk factors in the mean platelet volume (MPV). Methods A total of 562 patients with cerebral infarction and type 2 diabetes mellitus (DM) and 216 cerebral infarction patients without DM (non-DM) were included in this study. The platelet parameter of peripheral blood and other laboratory indexes were detected including platelet count (PLT), MPV, platelet distribution width (PDW), plateletcrit (PCT), fasting blood glucose (FBG), glycosylated hemoglobin (HbA1c), triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL-C), low density lipoprotein (LDL-C) and very low density lipoprotein (VLDL-C), urea nitrogen (BUN), creatinine (Cr), uric acid (UA), high-sensitivity C-reactive protein (hs-CRP) and homocysteine (HCY). The patients were scored by the National Institute of Health stroke scale (NIHSS) after hospitalization. The MPV changes in patients with cerebral infarction were observed, and different influences of blood glucose, blood lipids to MPV were analysed. Results Values of FBG, HbA1c, TC, TG, LDL-C, BUN, UA, HCY, hs-CRP, and NIHSS were significantly higher in DM group than those of non-DM group. The score of NIHSS was significantly higher in DM group than that of non-DM group. The level of HDL-C was significantly lower in DM group than that of non-DM grou. The MPV was significantly higher in DM group than that of non-DM group [(9.60 ± 1.35) fL vs. (9.27 ± 1.01) fL, P<0.05). There was a positive correlation between MPV and FBG, HbA1c, hs-CRP, WBC, VLDL-C and NIHSS, r=0.438, 0.410, 0.336, 0.164, 0.321 and 0.249 (P<0.05). Multiple regression analysis showed that FBG, VLDL-C, HbA1c, hs-CRP and NIHSS were the independent influential factors of MPV (P<0.05). Conclusion The influencing factors of MPV should be controlled in patients with cerebral infarction combined with type 2 diabetes mellitus, reducing the activation of platelet, and delaying the progress of cerebral infarction.

Objective To introduced the clinical application and indication of treatment the fractures of the base of the first metacarpal with mini external fixator. Methods From October 2002 to December 2004, 37 cases of different typical fractures of the base of the first metacarpal were treated with mini external fixator and followed up, which included type Ⅰ (Bennett fracture) 19 cases, type Ⅱ (Rolando fracture) 10 cases, type Ⅲ 8 cases. Defferent operations were applicated accroding to the fresh degree and classification of fractures. In type Ⅰ and fresh type Ⅱ fractures, closed reduction and fixation with mini external fixator were applicated at first. If the reduction was insatisfied, open reduction and fixation with Kirschner wire and external fixator were necessary. In old type Ⅱ fractures, open reduction associating internal and external fixation was applicated. In fresh type Ⅲ fractures, close and external fixation were applicated. In old type Ⅲ fractures, open reduction and external fixation were done. Results All the cases were followed up average 15 monthes and all the fractures were union successfully. The average union time were 5.5 weeks and 7.5 weeks in the fresh and old fractures. Function evaluation was made according to pain degree, thumb joint activity and proportion of traumatic arthritis. The overall good-excellent rate was 94.6%, the clinical results were satisfactory. Conclusion Treatment of fractures of the base of the first metacarpal with mini external fixator is better than conventional methods. This method is simple and reliable, and may shorten heal time, decrerase joint pain, limitation of joint movement and proportion of traumatic arthritis. It is an effective method in treatment of fractures of the base of the first metacarpal.

Objective:To study the expressions of Skp2 and P27 in the normal and tumor tissues of salivary glands,and then to evaluate their significance in the development and progression of salivary tumor.Methods:SP immunohistochemical method was used to evaluate the expression of Skp2 and P27 in the normal and tumor tissues of salivary glands. Results:The rates of Skp2 and P27 expression were neither significantly different between polymorphic adenoma and basal cell adenomas, nor significantly different between adenoid cystic carcinoma and mucoepidemoid carcinoma. The rates of Skp2 positive were significantly different between normal salivary glands and benign salivary tumor, as well as between normal salivary glands and malignant salivary tumor. The rates of Skp2 and P27 positive were significantly different between normal salivary glands and malignant salivary tumor.Conclusion:Skp2 overexpression and decreased expression of P27 might play an important role in the development and progression of salivary tumor, overexpression of Skp2 protein may lead to increase of P27 degradation.

Objective To compare and analyze the clinical effects and reliabilities of intermandibular flexible distraction and rigid internal fixation in treating mandibular condylar fractures. Methods Of 40 patients with mandibular condylar fractures, 21 cases were managed with intermandibular flexible distraction (external fixation group, Group A) and 19 with rigid titanium internal fixation (internal fixation group, Group B). There were 15 cases with high position fractures and 25 with low position ones. Results During 2-4 weeks postoperatively, X-rays confirmed the condylar fracture healing in all cases with no loosened mini-tinum plates in the Group B. There were 10 cases in the Group A and 14 cases in the Group B with the opening width over 30 mm, and 11 cases in the Group A and 5 in the Group B with the opening width less than 30 mm. Conclusions Both external and internal fixations can attain condylar fracture healing. However, compared with the internal fixation, the reduction of external fixation is less exact and the function recovery slower after operation, especially in the low position fractures. No irreversible damages on TMJ happen in all cases.

Forty cases of unilateral low- frequency sensorineural hearing loss(LFSNHL) were analysed. The symptoms included tinnitus(87.5% ), deafness(75% ), vertigo(35%) and ear fullness(25% ). Audiome-try showed LFSNHL in all cases. The threshold difference between low frequencies and high frequencies was 26. 32 dB. The cause of LFSNHL, the relation between tinnitus, LFSNHL and endolymphatic hydrops were discussed. We hope that the diagnosis of LFSNHL should be standardized.

[Objective]To modify posterior lumbar interbody fusion for improvement of convenient manipulation and safety in the operation,and solid fusion. [Methods]After total decompression of the spinal nerve through posterior medline approach,discectomy of the slipping segment was performed with a circular saw with diameter of 1.0 centmeter.Under direct visualization through the hole of the circular saw,the disc tissue including cartilage of upper and lower end plates was removed with a long handle curette.After pedicle screw and rod system was placed,a bone block harvested from the posterosuperior iliac with a circular saw with diameter of 1.2 centmeter was implanted into the intervertebral space.Then compression of the intervertebral space to catch the bone lock firmly was conducted by regulating and fixing the the pedicle screw and rod system.[Results]Forty-eight patients in this report were followed up from 6 to 24 months.Based on JOA low back pain score,there were 36 patients was in excellent result,8 in good and 4 in fair,the satisfactory rate was 91.67% and effective rate was 100%.[Conclusion]Using circular saws in posterior lumbar interbody fusion has advantagas of good visualization profit removing disc tissue,preventing neurovascular injuries,and making good bone grafting bed.Convenient and secure bone harvesting decrease blood loss,time consume during the operation and prevent donor site complication.Futhermore,follow up results of the patients in this report demonstrate that posterior interbody fusion with circular saw for treatment of lumbar spondylolisthesis have satisfactory outcome and high fusion rate.