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

AIM: To investigate expression of CD44s in lung cancer and it's clinical significance. METHODS: A total of 117 primary lung cancer from patients were examined for CD44s expression by immunohistochemical staining. RESULTS: CD44s mostly expressed in non-small cell lung cancer (NSCLC) but not in small ecll lung cancer (SCLC), and squamous cell carcinoma(SCC) showed much stronger expression of CD44s than adenocarcinoma(ADC)(P

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.

Objective To evaluate the safety of compound Qinghuang powder for myelodysplastic syndromes(MDS). Methods A total of108 patients with MDSwere collected, 60 patients were treated with Qinghuang powder(Qinghuang powder group)and 48 with compound Qinghuang powder(compound Qinghuang group). The treatment time of 3 months was as one course, and all the patients were treated for more than one course. The patients who developed adverse reactions in the Qinghuang powder group changed to receive compound Qinghuang powder. The adverse reactions were recorded during the treatment. Results The overall incidence of adverse reactions in the compound Qinghuang powder group was significantly lower than that in the Qinghuang powder group(18.75% vs. 41.7%; χ2=6.492, P<0.05). None in the compound Qinghuang powder group and 3 patients in the compound Qinghuang powder group developed moderate to severe adverse reactions. The incidences of various adverse reactions in the compound Qinghuang powder group were lower than those in the Qinghuang powder group, especially, lower limb swelling (4.17%vs. 25%;χ2=9.205, P<0.05) epigastric discomfort(18.75% vs. 41.67%; χ2=6.492, P<0.05). Twenty patients who developed adverse reactions in the Qinghuang powder group changed to receive compound Qinghuang powder. Among them, 5 patients (25%) maintained adverse reactions. The various adverse reactions after changing to compound Qinghuang powder were decreased, especially, facial swelling (10% vs. 30%; χ2=2.50, P<0.05), leg swelling (5%vs. 45%;χ2=8.533, P<0.05), and abdominal pain and diarrhea(10%vs. 30%;χ2=2.50, P<0.05). No patient developed liver or kidney dysfunction after the treatment with Qinghuang powder or Compound Qinghuang powder. Conclusion Compound Qinghuang powder is safer than Qinghuang powder in the treatment of MDS.

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 understand occupational stress and burnout status of nurses working for general or cancer hospitals of Xinjiang so as to provide a theoretical basis for the prevention and reduction of occupational stress and burnout of nurses.Methods A total of 497 nurses from a general hospital or a tertiary-level cancer hospital were recruited by using random sampling to learn their occupational stress and burnout.Results Of 497 participants,247 were working for comprehensive hospitals and 250 for cancer hospitals.In comparison with the norm,the nurses of general hospitals showed higher scores in occupational task dimension (t=14.316,P＜0.05) and personal strain dimension (t=25.416,P＜0.05),but lower scores in personal resource dimension (t=7.389,P＜0.05).Meanwhile,the nurses of cancer hospitals were found to have higher scores in occupational task dimension (t=15.840,P＜0.05) and personal strain dimension (t=15.694,P＜0.05),but lower scores in personal resource dimension (t=7.488,P＜0.05) when compared to the norm.Those working in general hospitals had higher scores in emotional exhaustion dimension (t=13.109,P＜0.05) and passive burnout dimension (t=13.198,P＜0.05) than the norm,while lower scores in professional sense dimension (t=17.716,P＜0.05).The nurses of cancer hospitals were observed to show higher scores in emotional exhaustion dimension (t=8.044,P＜0.05) and negative burnout dimension (t=1 1.111,P＜0.05) than the norm,while lower scores in professional sense dimension (t=20.820,P＜0.05).Conclusions Hospital managers should take efforts to control nurses' occupational stress and burnout-related factors so as to enhance their work initiative.

Aim To observe the effect and primary mechanism of arctigenin ( ARG) in C6 rat glioma. At the same time, to investigate the effect of ARG com-bined with temozolomide. Methods C6 glioma rat model was established, and 90 rats were divided into six groups, which were subcutaneously administered with model, low and high ARG (0. 05 and 0. 1 mg· kg-1 , sc) , temozolomide (20 mg·kg-1 , p. o. ) , low ARG combined with temozolomide(TMZ / ARG 0. 05) and high ARG combined with temozolomide ( TMZ /ARG 0. 1 ) . The tumor specimens of brain were col-lected after tumor graft. Proliferating cell nuclear anti-gen ( PCNA ) , glial fibrillary acidic protein ( GFAP ) and CD40 in tumor specimens were determined by im-munohistochemistry. Results ① Compared with the model group, the tumor sizes of rats in the arctigenin treatment groups were decreased ( P<0. 05 ) . ②ARG
significantly decreased PCNA and CD40 expression ( P<0. 05 ) and increased GFAP expression ( P<0. 05 ) .③ Compared with model group, arctigenin combined with temozolomide decreased the tumor sizes ( P <0. 01 ) , and the tumor inhibition rate was higher than that of the arctigenin and temozolomide. At the same time, arctigenin combined with temozolomide de-creased PCNA and CD40 expression ( P <0. 01 ) and increased GFAP expression ( P <0. 05 ) , which was better than arctigenin and temozolomide. Conclusion Arctigenin inhibits rat glioma growth, and synergizes with temozolomide, which may be associated with in-hibiting PCNA and CD40 expression and strengthening GFAP expression.