Objective:To compare the effect of four different techniques on removal of vapor lock in the apical region of curved root canals.Methods:Forty simulated resin root canals with 45° curvature were prepared using WaveOne Primary,then the apical foramen were sealed with soft wax.The teeth were divided randomly into 4 groups thereafter (n =10).Contract solution was injected into the canals using a 30 G side-vented needle and scanned with cone-beam CT (CBCT) to identify the volume of the vapor lock.Four different techniques including photon-induced photoacoustic streaming (PIPS) laser-activated irrigation,gutta-percha cone technique,ultrasonic irrigation,and sonic irrigation were used to remove the vapor locks in the root canals.The residual volume of the vapor lock was identified again using CBCT scanning data.Accordingly,the reduction rates of the vapor lock were calculated.Furthermore,the initial and residual vapor lock length was calculated.The data were analyzed by using the One-Way ANOVA analysis and Kruskal-Wallis H test at a significance level of P ＜ 0.05.Results:There was no significant difference in the initial vapor lock volume (P ＞ 0.05).Residual volume of the vapor lock for PIPS laser-activated irrigation was 0 mm3,and that for gutta-percha cone technique was (0.02 ± 0.07) mm3,significantly lower than those of ultrasonic and sonic irrigation,the values being (0.20 ± 0.09)mm3 and (0.23 ±0.06) mm3 (P ＜0.001),respectively.The reduction rates of the vapor lock of PIPS laser-activated irrigation and gutta-percha cone technique were 100.00％ (100.00％,100.00％) and 100.00％ (77.66％,100.00％),respectively,significantly higher than those of ultrasonic irrigation [70.37％ (56.41％,91.43％)] and sonic irrigation [63.54％ (51.47％,74.00％),P ＜0.001].The length of the residual vapor lock for PIPS laser-activated irrigation was 0 mm,and that for gutta-percha cone technique was (0.15 ±0.47) mm,significantly lower than those of ultrasonic and sonic irrigation,values being (2.21 ±0.09) mm and (2.34 ±0.08) mm (P ＜0.001),respectively.The length of the residual vapor locks in the ultrasonic and sonic group remained approximately the same as the distance between the working tip and the apical foramen.Conclusion:PIPS laser activated irrigation and gutta-percha cone technique could remove the vapor lock from the apical region of curved canals effectivelv.

ObjectiveTo study the clinical and pathological characteristics of tubulointerstitial nephropathy associated with Chinese herb patent Guan Xin Su He Wan(GXSHW-TIN).Methods15 patients with GXSHW-TIN were studied.Clinical and pathological data were semi-quantitatively assessed.Relationships between medication and the incidence,clinical characteristics and the outcome of the disease were analyzed.ResultsAll the patients had chronic renal failure when GXSHW-TIN was diagnosed.They all got the disease after long-term taking of GXSHW in routine dosage.Most of the patients presented gastrointestinal dysfunction,abnormal urine analysis and mild to moderate anemia as onset symptoms.The pathological characteristics were similar to those of Guanmutong(Aristolochia manshuriensis Kom) induced chronic aristolochic acid nephropathy(AAN).ConclusionLong-term taking of GXSHW,which contains Radix Aristolochiae,might induce AAN.It indicates that GXSHW should be causious for clinical use,the ban of Radix Aristolochiae in the pharmaceutical market needs to be considered for prevention of AAN.

BACKGROUND: Attachment reflects the early social experience of infant, which plays an important role in later child development. Although most of the attachment develops between infant and mother, some may occur between infant and care giver or others who have close relationship with it.OBJECTIVE: To analyze the infant-mother attachment patterns and the factors related to infant attachment.DESIGN: It was a sampling investigation.SETTING: Department of Maternal and Child Health, School of Public Health, Sun Yat-sen University.PARTICIPANTS: Totally 75 infants and their mother were selected randomly for this study in the Department of Child Health in Guangdong Maternal and Child Health Hospital from August to October 2002.METHODS: Strange situation test (SST) was performed by 6 researchers who were trained systematically. They watched the videos collectively and classified the patterns of infant attschment based on their performance. The internal consistency coefficient was 0.90. For those inconsistent assessments, the video should be reviewed and discussed to get an accordant conclusion. In addition, a self-designed maternal questionnaire was used to investigate the general condition of the infant and the familial information.MAIN OUTCOME MEASURES: ①Distribution of infant attachment patterns. ②Analysis of the risk factors related to infant attachment.RESULTS: All the 75 infants and their mother entered the statistical analysis. ①Distribution of the infant attachment patterns: In 75 infants, secure attachment was 65% and insecure attachment was 35%, among which,insecure-indifferent type was 18%, insecure-importunate type was 13%,and insecure-disorganized type was 4%. ②Analysis of the risk factors related to infant attachment Those infants with a younger age, a poor approachability (the response to strangers, new environment and objects), a closer relationship with caregiver and a more inconsistent education from the family members, are prone to develop insecure attachment.CONCLUSION: Secure attachment is dominant in infants. The security of attachment is related to the maturity and personality traits of the infants,the relationship between infant and caregiver and the educational approach for them. Key words Object attachment; Infant; Factor analysis, statistics

Objective: To evaluate effect of the morphology of simulated S-shaped root canals with Reciproc or Mtwo instruments on root canal irrigation. Methods: A total of 40 simulated S-shaped resin blocks were randomly divided into 2 groups (n=20), which was prepared by Reciproc or Mtwo. Blue ink was injected with constant speed and volume into the canals using 30G lateral opening syringe. hTe distance from needle tip to apex and vapor lock length were measured. A type of 25# 0.04 gutta-percha point was used to stir and remove the vapor lock. hTe time for removal of the vapor lock was recorded. Another syringe was used to inject saline into the canals and to measure the length of stagnant water. Results: hTe distance from needle tip to apex in the Reciproc group was signiifcantly longer than that in the Mtwo group [(4.276 ± 0.221) mm vs (3.459 ± 0.205) mm,P<0.05]. The vapor lock length in the Reciproc group was signiifcantly longer than that in the Mtwo group [(4.472 ± 0.230) mm vs (3.668±0.217) mm,P<0.05]. hTe time to remove vapor lock was signiifcantly shorter in the Reciproc group than that in the Mtwo group [(10.13 ± 1.79) s vs (15.29 ± 2.15) s,P<0.05]. The length of stagnant water was also shorter in the Reciproc group than that in the Mtwo group[(1.351 ± 0.142) mm vs (2.245 ± 0.206) mm,P<0.05]. Conclusion: hTe morphology of S-shaped root canal affects the root canal irrigation. hTe effect of root canal irrigated by Reciproc is better than that by Mtwo.

Objective:To investigate the anti-inflammation effects by activation of the cholinergic anti-inflammatory pathway and its mechanisms in non-alcoholic steatohepatitis (NASH)model mice.Me-thods:6-week-old male C57BL/6J (B6)mice were randomly divided into four groups:the first group was normal mice,injected with saline;the second group was normal mice,injected with nicotine;the third group was NASH model mice,injected with saline;the fourth group was NASH model mice,injec-ted with nicotine.The experimental mice were fed with either standard chow (SC)or high-fat and high-fructose (HFHF)for 17 weeks to generate an NASH model mice.The mice received injection once daily for 3 weeks [nicotine dose,400 μg/kg].Then,their pathological characteristics and function of the liver were assessed.The expressions of interleukin-6 (IL-6)and tumor necrosis factor-α(TNF-α)in se-rum were analyzed by enzyme linked immunosorbent assay (ELISA).The expressions of alpha 7 nicotinic acetylcholine receptors (α7nAChR),Toll-like receptors-4 (TLR-4)and nuclear factor κB of phosphory-lation (p-NF-κB)in Kupffer cells were determined by Western blot and immunofluorescence assays.Re-sults:We successfully generated NASH model mice by imitating the high-fat and high-fructose dietary style of NASH patients.The results of our investigation demonstrated that nicotine could reduce signifi-cantly the levels of IL-6,and TNF-αin serum (P <0.05).The expression of p-NF-κB protein in the group which was NASH model mice injected with nicotine declined significantly as compared with the group which was NASH model mice injected with saline (P <0.05).And the expression of α7nAChR protein elevated significantly conversely (P <0.05 ).Conclusion:Activation of the cholinergic anti-inflammatory pathway could inhibit the release of inflammatory factors as TNF-αand IL-6 in NASH model mice,and the mechanism for the inhibition of inflammatory was mediated by NF-κB pathway.

AIM and METHODS: The immunohistochemical method was used to study the on synapsin ex- press in hippocampal formation during spatial learning and memory in rats. RESULTS: (1 ) In control group there are diffuse brown granules without any obvious granular product in hippocampal fornation and in model group there are synapsin products in the hippocampal formation, especially in the subregion CA3, CA4 and the dentate gyrus after water maze flamed for one week. After two weeks water maze thened the hippocampal formation appear the same dis- tribution of the product edes with darker staining. (2) The light dendity of synapsin products between the model and the control groups showed significant differences, that in the model group was highter than that in the control group (P

Temporal and spatial expressions of ?-catenin investigated in the hair follicle and epidermis of the hoof periphery in bovine embryonic development. IHC (immunohistochemical method) was applied to qualitatively detect the temporal and spatial expressions of ?-catenin. ?-catenin was detected in suprabasal, epidermal basal layer, placode, hair bud in early phase(E68～93),and expressed strongly in epidermal basal layer, placode, and hair bud, in suprabasal expressed less strongly; in metaphase(E94～184), ?-catenin was detected in epidermis, hair peg, and in suprabasal, epidermal basal layer, hair follicle bulge, inner root sheath, outer root sheath, follicular infundibulum expressed less strongly; in late phase(E184～225), ?-catenin expressed weakly in epidermal basal layers, while expressed strongly in epidermal keratinocytes. The result suggested that ?-catenin plays an important role in hair follicle morphogenesis in the periphery of bovine hoof in bovine embryos.

Objective To genotype strains producing ESBLs in Escherichia coil and Klebsieua pneumoniae to provide references for the clinical application of drugs.Methods PCR was used to determine the genotype of the ESBLs.Results The percentage of TEM type,SHV type and NO-TEM-NO-SHV type in Escheroichia coil was 80.4%,7.8% and 11.8%,in Klebsieua pneumoniae was 78.1%,71.9% and 25.0%.Most of Klebsieua pneumoniae produced more than two Extended Spectrum ?-lactamases.Conclusion The difference in the distribution of genotypes in different regions is confirmed.

OBJECTIVE To study the measures of strengthening the nursing management in the nursing department to prevent and control nosocomial infection.METHODS Establishing nosocomial infection management organization;staff training;modifying the related rules and regulations;setting up the supervision and inspection system;and academic research of nosocomial infection were taken.RESULTS All nurses consciously implemented the rules.The systems of nosocomial infection control had developed and standardized and the rate of nosocomial infection have decreased.CONCLUSIONS Strengthening the nursing management in the nursing department could effectively prevent and control nosocomial infection.

Contemporary medical education not only demands medical students to master knowledge of medical science and to possess good professional ethics and advanced duty, but also possess comprehensive quality, especially nice humane quality. So it is necessity to medical students for growing them into medical talent of advanced quality.