Objective:To study the torsional property and rotary fatigue fracture of Smart K files and R reamers made of nickel-titanium alloy. Methods:The torsional property and rotary fatigue fracture behavior of Smart K files and R reamers were evaluated by means of specially-designed torsional device and simulated endodontic root canals system. The instrument surface and the rotary fatigue fractured surface were investigated by optical microscope and scanning electron microscope. Results:Compared with ANSI/ADA specification No.28, maximum torque values of Smart K and R endodontic instrument were higher. Tensile stresses on the outer surface of the endodontic instruments played a dominant role in fracture initiation during rotary fatigue fracture. The rotary numbers corresponding to rotary fatigue fracture decreased with the increase of the instrument size and curvature. Smart K and R endodontic instruments exhibited good ductility. Dimples were found on the fractured surface, and the fatigue fracture was the typical ductile fracture. Conclusion:Smartendodontic instruments have excellent torsional and rotary fatigue fracture resistance properties.

BACKGROUND:Study on antisense drug is still one of hotspots in the current field of biomedicine. Due to high-efficiency and specificity, antisense drug used for gene therapy has been paid more attention by many scholars.OBJECTIVE: To observe the effect of liposome-mediated keratin 14 (K14) antisense oligonucleotide on K14 gene and protein expressions as well as in vitro proliferation activities in human keratinocytes (KC).DESIGN: Single sample observation.SETTING: Department of Dermatology, Xijing Hospital, Fourth Military Medical University of Chinese PLA.MATERIALS: Human KC, K14 oligonucleotide gene fragments (modified with phosphrothioate, and above sequence was synthesized by Shanghai Shenggong Bioengineering Company). Reverse transcriptase and TaqDNA polymerase were purchased from Invitrogen Company, K14 monoclonal antibody was purchased from Antibody Company, and SABC kit was purchased from Boster Company. EPICS-PRO-FILE Ⅱ flow cytometer was purchased from Coulter Company (USA).METHODS: Human epidermal KCs were primarily cultured, and their 3rd to 10th generations were used for the experiment.Artificially synthesized sense and antisense as well as mismatched K14 oligonucleotide gene fragments were introduced into KCs by means of liposome. Blank control group were set. The effects of antisense oligonucleotide on the cell cycle,K14 gene and protein expressions of KCs were detected by flow cytometer, reverse transcription polymerase chain reaction and SABC methods.MAIN OUTCOME MEASURES: Effect of oligonucleotide transfecting human KCs on the proliferation of KCs and K14 expression.RESULTS: [1]The electrophoresis of reverse transcription polymerase chain reaction products: Specific K14 gene band appeared in each group, and K14 gene expression in the antisense group was significantly lower in the sense group,missense group and blank control group. K14/β-actin value was similar among sense group, missense group and blank control group (P ＞ 0.05), But K14/β-actin value was significantly lower in the antisense group than in the above-mentioned 3 groups (F =47.554, P ＜ 0.01). ②K14 protein expression detected by immunohistochemical method:K14 was expressed in all the cultured KCs at different levels, and was obviously reduced after antisense oligonucleotide being added. 20 μmol/L antisense oligonucleotide could markedly inhibit K14 expression; K14 expression did not change in the control group. ③ DNA level change detected by flow cytometer: After being treated by K14 antisense oligonucleotide for 48 hours, human epidermal KCs were significantly increased at G1 stage (74.6%), and were markedly decreased at S stage (19.4%). Such changes were not found in the antisense group, missense group and blank control group.CONCLUSION: Antisense oligonucleotide can specifically inhibit K14 synthesis, and thereby, inhibit the proliferation of human KCs.

Objective To investigate the visual spatial attention of occipital stroke patients with hemianopia during the acute phase.Methods Eight occipital stroke patients with homonymous hemianopia of left side in the acute stage and 10 age-matched healthy controls were recruited to examine the capability of visual spatial attention.The cue-target paradigms were applied in this behavioral research.Results In the repeated measures analysis of variance,the difference of group and cue range had distinct main effect in reaction time and accuracy rate,while the difference of target location only had main effect in reaction time.Compared with the control group,the patients exhibited longer reaction time ((1 628.26 ± 183.97) ms vs (839.79±61.29) ms,F(1,16) =163.706,P＜0.05) and lower accuracy rate (73.40％ ±3.12％ vs 92.99％ ±0.76％,F(1,16) =371.850,P ＜ 0.05).The patients displayed lower accuracy rate under large cue than small cue (71.38％ ±3.35％ vs 75.42％ ±4.23％,F(1,7) =6.706,P ＜0.05),while that of healthy controls did not vary under different cue range(93.01％ ± 0.50％ vs 92.96％ ± 1.42％,F(1,9) =0.010,P ＞ 0.05).The patients showed longer reaction time in blind-side target than healthy-side target ((1 664.17±196.57) msvs (1 594.35±174.45) ms,F(1,7) =14.157,P＜0.05),while that of control group in two target location had no statistically significant difference ((839.67 ± 60.41) ms vs (839.91 ±73.54) ms,F(1,9) =0.000,P ＞0.05).Furthermore,the mean reaction time of stroke patients had a negative correlation with the binocular vision field index (r =-0.824,P ＜ 0.05).Conclusions The extent of vision field loss in occipital stroke patients with hemianopia can reflect impairment of visual spatial attention during the acute phase.The rehabilitation training should emphasize promoting recovery of visual spatial attention in the blind side under large cue.

Objective To explore the effects of directive game in preoperative visit of preschool children with strabismus.Methods 109 children were randomly assigned into the control group and the experimental group.The control group was given conventional preoperative interview,based on the general preoperative visit,the experimental group was given preoperative visit-playing directive game.The nursing effect was compared be4wecn two groups.Results Induction compliance scores of the experimental group were obviously higher than those of the control group.Preoperative anxiety scores of the experimental group were obviously lower than those of the control group.Restlessness during recovery of the experimental group was obviously lower than that of the control group.Conclusions The application of directive game can reduce preoperative anxiety of the children with strabismus,and make children cooperate better with the induction of anesthesia.

Objective To investigate the distribution of Human Papillomavirus 16 (HPV16) infection and its mixed infection with other HPV subtypes in the Yunnan region. Methods 16 166 cases of women were tested using flow fluorescence Luminex technology. Results (1) HPV16 infection rate and mixed infection rate was 2.2%and 28.0%, respectively; (2) The most common type of HPV16 mixed infection was HPV52, followed by HPV33. The two kinds of mixed infection accounted for 39.8% of the total infection rate; (3) There was a significant difference between each age group of HPV16 mixed infection (Chi=26.39, <0.01) . Conclusion The HPV16 infection was mainly HPV infection in Yunnan region. HPV16 mixed infection merged mainly with HPV52 and HPV33. HPV16 mixed infection was associated with age.

Objective To evaluate the practical efficacy of comparison method in experimental teaching of pathological anatomy.Methods The junior college students of stomatology were divided into experimental group (n =48) and control group (n =48) randomly.Students in experimental group adopted the experimental teaching with comparison method of pathological anatomy and histology while those in control group followed the traditional experimental teaching.Experiment examination results of two groups were compared and questionnaire investigation was carried out among students in experimental group.Results Average score of experiment examination in experimental group was (88.35 ±5.68) while that in control group was (78.35 ±4.86),with statistical differences (P ＜0.01).The results of questionnaire investigation showed that students in experiment group preferred comparison teaching method.Conclusions Comparison teaching method is feasible,the mechanism of which emphasizes gaining new knowledge by reviewing the old and strengthens the contact of basic subjects,therefore it is conducive to enhancing the quality of pathological experimental teaching.

Objective To investigate the dynamic level changes and significance of triggering receptor expressed on myeloid cells-1 (TREM-1) in the injury brain tissues of rats caused by pneumolysin (PLY).Methods Sixty-four SD rats were randomly and equally divided into PLY group and control group,0.1 mL PLY and isopyknic normal saline was given through left internal carotid artery respectively.Brain tissue gross and histological changes were observed at different time(4 h,6 h,12 h,24 h),meanwhile the expression levels of neurocyte damage marker glial fibrillary acidic protein (GFAP) and neuron-specific enolase (NSE) protein were detected by immunohistochemistry;and the expression levels of TREM-1,tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) were detected respectively by enzyme-linked immunosorbent assay.Results The observation of brain tissue gross and histological changes indicated the existence of brain injury,and the expression levels of GFAP,NSE,TNF-α and IL-6 protein increased from 4 h after PLY were injected and augmented dynamically as time went on,compared with the control group at corresponding time points,the differences were statistically significant (all P ＜ 0.05).The level of TREM-1 in the PLY group reached a peak at the 4 h time point,but decreased somewhat at the 6 h time point,the level of TREM-1 was still higher than that in control group,the differences were statistically significant(all P ＜ 0.05).However,the level of TREM-1 in the PLY group declined obviously at 12 h and 24 h time points,compared with that in control group,there were no significant differences (all P ＞ 0.05).Conclusions The expression levels of TREM-1 up-regulated obviously in the early stage of brain damage induced by PLY,which might be involved in the pathological process of brain damage by promoting the expression of TNF-α and IL-6.

Objective To investigate the preventive effect of intrarectal application of indomethacin on hyperamylasemia and acute pancreatitis after endoscopic retrograde cholangiopancreatography ( ERCP ) .Methods 180 patients who underwent ERCP were randomly divided into the indomethacin group, somatostatin group and control group.The serum amylase levels were measured before ERCP, 3 and 24 hours after the drug application.The incidences of post-ERCP hyperamylasemia and pancreatitis were observed.Results Serum amylase levels before and 3h after ERCP of three groups had no differences.The serm amylase levels of control group 24 h after ERCP (228.50 ±121.72) U/L was significantly higher than that of indomethacin group (94.09 ±68.45) U/L (P <0.01) and somatostatin group (76.53 ±74.47) U/L (P <0.05), while there was no difference between indomethacin group and somatostatin group.Compared with before ERCP, the serum amylase levels significantly increased in both control group 3 and 24h after ERCP (P <0.01), as well as in both indomethacin group and somatostatin group 3h after ERCP (P <0.05), but there were no apparent differences between pre-ERCP and 24 h after ERCP in both indomethacin group and somatostatin group.The incidences of post-ERCP hyperamylasemia in both indomethacin group and somatostatin group ( 10.00%, 11.67%) respectively was much lower than that in control groups (35.00%, P<0.01).The incidence of post-ERCP pancreatitis in indomethacin group (3.33%) was also lower than that in control group (15.00%, P<0.05), whlie there was no difference between indomethacin group and somatostatin group (5.00%).Conclusion The intrarectal application of indomethacin can effectively prevent acute pancreatitis after ERCP, which has the same effect as intravenous application of somatostatin.It is also convenient, economic and safe.

OBJECTIVE:To optimize the extraction technology of oleanolic acid from Elsholtzia bodinieri V.METHODS:The extraction technology was optimized by orthogonal-test using microwave-assisted dynamic extraction method with oleanolic acid as index;And the content of oleanolic acid was determined by TLC-spectrophotometry.RESULTS:The opti-mum extraction condition was described as follows,the microwave power is600W with methanol as extracting solvent,the flow rate was8ml/min and the inner diameter of extraction tube was10mm.CONCLUSIONS:The microwave-assisted dynamic extraction method is simple,safe,rapid,accurate and with high extraction yield.The optimized extraction technology is stable and feasible,and suitable for industrialized production.

Objective　To observe the therapeutic effect of combination of penetrating keratoplasty, cataract extraction and intraocular lenses implantation.Methods　Penetrating keratoplasty was performed simultaneously with cataract extraction and intraocular lenses implantation on 134 cases. Results　One hundred and twenty cases were recorded after following up for 0.5～12 years. Ninety-nine cases (82.5%)of the corneas remained clear. Twenty-one cases (17.5%)of the corneas failed.Ninety-two cases (76.7%)achieved a better visual acuity postoperatively.Eighty-nine eyes(74.2%)were not blind any longer. Conclusion　The combination of penetrating keratoplasty, cataract extraction and intraocular lenses implantation offers advantages of rapid and better rehabilitation of visual acuity with low complication rate.