OBJECTIVETo assess the temperature variation of the root surface using Nd: YAG laser irradiation in the root canal with different power and to evaluate the safety of laser application on the periodontal region.

METHODSThirty extracted human teeth with single-roots were collected. The teeth were cross-sectioned in the cervical portion, standardizing the roots at a 12-mm length. The roots were used as specimen. The roots were radiographed in the buccal-lingual direction to measure the thickness of the proximal walls, by means of a digital radiographic system. The specimens were divided into three groups according to the laser potency (1.5, 3.0, and 4.5 W). Each group was subdivided into two subgroups according to laser frequency (15 and 30 Hz). With the Nd: YAG laser irradiation for 20 s, the temperature variation of the root surface was monitored by thermocouples located at different parts of the root external wall and recorded by digital thermometers.

RESULTSThe groups irradiated with 4.5 W presented the greatest temperature variation (above 10°C), followed by 3.0 and 1.5 W. The temperatures were statistically different (P < 0.01). The groups irradiated in the same potency, regardless of whether 15 Hz or 30 Hz was used, presented with no statistical difference (P > 0.05). The apical half of the root presented statistically higher temperature rises than the cervical half of the root (P < 0.01).

CONCLUSIONThe temperature variation of the root surface was associated with laser power, irradiation time, and the thickness of dentin. Application of Nd: YAG laser in the root at 1.5 W for 20 s can safely be used in endodontic treatment.

Objective:To observe the temperature vaxiation in the pulp chamber during Nd-YAG laser irradiation at tooth cervical portion.Methods:60 extracted permanent teeth were divided into 3 groups (anterior teeth,premolars and molars,n =20).The teeth in each group were further divided into 4 subgroups according to the laser power setting (0.4 W,0.8 W)and interval time(1 0 s,20 s)(n =5).After canal preparation the teeth were fixed and filmed using the parallel projection technique.the thickness of the buccal pulp chamber wall was measured by graphic analyzing software.The buccal cervical portion of the teeth was irradiated through 200 μm optical fiber,Temperature in the pulp was measured by K type thermo-electric couples fixed to the pulp chamber wall.Re-sults:The temperature inside the chamber increased with the higher power setting(P <0.01 ),under the same power setting,longer irradiation duration caused higher temperature rise(P <0.01 ).Greater chamber wall thickness was associated with lower temperature rise.Conclusion:The temperature rise in the pulp chamber during laser irradiation is correlated with laser power setting and the thickness of the irradiated tooth tissue.

The kinetic changes in morphology and cellular density of epidermal Langerhanscells (LC) in the guinea pig were observed by ATPase cytochemical staining techniqueafter repeated skin application of 5%,3% and 1% of benzalkonium bromide (BB,primary irritant) and 0.05% dinitrochlorobenzene (DNCB,allergen) respectively.We have found that there was a significant difference in the density and morpho-logical change of LC between BB and DNCB application.Treatment with 5% BBcould induce a reversible decline in LC density and changes in cell processes,andwith 0.05% DNCB,the number of LC was decreased and the ATPase activity wasweakened only in the late stage of treatment.The significance of using the kineticchanges in morphology and cellular density of LC as the criteria for the safetyevaluation of weak allergens and weak primary irritants as well as cosmetics wasdiscussed.

Objective To investigate the effect of early coronary artery bypass grafting (CABG)to the left ventricular wall motion state and the significance of CABG to awake hibernating myocardial in dogs with acute myocardial infarction.Methods The anterior descending coronary of all thirty dogs were ligated into MI model.According to the operation date,the experimental groups included the 1 st week (n =6),the 2nd week (n =4),the 4th week (n =6) and the 6th week (n =6) CABG,and established control group (n =2) for every experimental group.Operators marked hibernate myocardial and determined the room wall motion score by means of dobutamine ultrasound load test (DSE) combining with tissue doppler imaging (DTI)technology before CABG and after eight weeks CABG through thoracotomy surgery for the experimental group and the control group.Every dog was executed and detected the area of MI.Results Four dogs of experimental group and all dogs of control group survived to the end of the study.The change of ventricular room wall motion score in the 1st and the 2nd week CABG was smaller than that in the 4th and the 6th week CABG and MI group(0.03 ±0.06,0.05 ±0.09,0.23 ±0.08,0.27 ±40.06,0.32 ±0.05,P ＜0.05).The change of room wall motion score in all CABG groups was smaller than that in MI group(1.195 ±0.09,1.25 ±0.18,1.30 ±0.18,1.36 ±0.11,1.65 ±0.17,P＜0.05).The hibernate myocardial were more awaken in all CABG groups than that in MI group (0.27 ± 0.12,0.22 ± 0.04,0.31 ± 0.09,0.23 ± 0.03,0.03 ± 0.04,P ＜ 0.05).The area of MI became smaller in 1 and 2 weeks CABG than that in 4 and 6 weeks CABG and MI group(20.75 ± 2.63,21.25 ± 2.5,27.25 ± 1.71,27.75 ± 2.22,P ＜ 0.05).Conclusions Early CABG surgery for dogs acute MI could improve the ventricular room wall motion obviously and wake up more hibernate myocardial.Especially,CABG surgery among two weeks could lessen the effect of MI to the ventricular room wall motion and reduce the scope of myocardial infarction maximatily.

The total effective rate for clinical symptomstreated with oral decoction with Weiweikang(benefit-ting atrophic stomach)granules and Huoli(vitality)Bolus guided by the principle of invigorating Qi,warming the interior,activating circulation and elimi-nating blood stasis,was 91.8%,while that for thechronic atrophic gastritis with metaplasia and atypicalhyperplasia of intestinal epithelium was 87.5% and74.4% respectively.After treatment,the volume ofblood flowing was markedly increased(P

Objective:To prepare old tea buccal tablets using wet granulation method and optimize the preparation technology. Methods:The amount of each adjuvant was studied by single factor experiments, and the formula of the buccal tablets was optimized by the orthogonal experiments using taste and disintegration time as indices. Results:The optimal formula was composed of old tea ex-tract 30 g,mannitol 60g,PEG6000 20 g,aspartame 10 g,citric acid 10 g and menthol crystal 1 g. All the tested indices including ap-pearance, hardness and disintegration time met the requirements described in Chinese pharmacopeia. Conclusion: The preparation technology is reasonable and feasible for the industrial production.

Objective:To establish the quality standard for Sipunculus nudus polysaccharide. Methods:The water content, igni-tion residues and heavy metals in Sipunculus nudus polysaccharide were determined. Authrone-sulfuric acid colorimetry was used to de-termine the polysaccharide content. Results: The water content in the polysaccharide should not exceed 5. 0%, ignition residues should not exceed 1. 0%, and the content of heavy metals should not exceed 20 ppm. The polysaccharide content should exceed 80%( glucose) . Conclusion:The method is accurate and simple, and can be effectively used in the quality control of polysaccharide in Sipunculus nudus Linnaeu.

Objective To assess the temperature variation of the root surface using Nd:YAG laser irradiation in the root canal with different power and to evaluate the safety of laser application on the periodontal region. Methods Thirty extracted human teeth with single-roots were collected. The teeth were cross-sectioned in the cervical portion, standardizing the roots at a 12-mm length. The roots were used as specimen. The roots were radiographed in the buccal-lingual direction to measure the thickness of the proximal walls, by means of a digital radiographic system. The specimens were divided into three groups according to the laser potency (1.5, 3.0, and 4.5 W). Each group was subdivided into two subgroups according to laser fre-quency (15 and 30 Hz). With the Nd:YAG laser irradiation for 20 s, the temperature variation of the root surface was moni-tored by thermocouples located at different parts of the root external wall and recorded by digital thermometers. Results The groups irradiated with 4.5 W presented the greatest temperature variation (above 10 ℃), followed by 3.0 and 1.5 W. The temperatures were statistically different (P<0.01). The groups irradiated in the same potency, regardless of whether 15 Hz or 30 Hz was used, presented with no statistical difference (P>0.05). The apical half of the root presented statistically higher temperature rises than the cervical half of the root (P<0.01). Conclusion The temperature variation of the root surface was associated with laser power, irradiation time, and the thickness of dentin. Application of Nd:YAG laser in the root at 1.5 W for 20 s can safely be used in endodontic treatment.

Objective To investigate the radioprotective effect of cimetidine on survival rate and hematopoietic system in acutely irradiated mice.Methods The total body irradiation doses were 6.0Gy and 8.0Gy respectively at 1.01Gy/min rate. Sixty healthy male C57BL/6 mice were randomly divided into control group, model group, positive-drug (523) group and cimetidine groups (33.3mg/kg, 100mg/kg and 300mg/kg). Each group had ten mice. The mice were given intragastric administration of cimetidine for 6d before the irradiation in cimetidine groups, and 523 was administered before irradiation once a day for one day in 523 group, and at 5h after irradiation, was given again. The 30d survival rate after 8.0Gy irradiation was recorded. The peripheral blood cells, bone marrow DNA content and frequency of micronucleated polychromatic erythrocytes (fMNPCE) were determined 30d after 6.0Gy irradiation.Results After 8.0Gy irradiation, all the mice died on 21th day in model control group. The survival rates in cimetidine groups were 50%, 20% and 30%, respectively. After 6.0Gy irradiation on 30th day, compared with control group, the peripheral white blood cells (WBC) and bone marrow DNA content were decreased significantly (P<0.01,P<0.05) in model group, and fMNPCE was increased significantly (P<0.05). Compared with model group, WBC was significantly increased in 300mg/kg cimetidine group (P<0.01). In cimetidine groups, the bone marrow DNA content was increased significantly after irradiation (P<0.01 orP<0.05), and the fMNPCE was decreased significantly (P<0.01 orP<0.05) and tended towards normal.Conclusion Cimetidine could improve 30d survival rate of acutely irradiated mice and has good protective effect on hematopoietic system.

Objective:To establish a scientific and standardized routine for perioperative nursing in pediatric otolaryngology, reduce the incidence of postoperative delirium, and improve the quality of postoperative recovery by implementing the best practice of evaluation and intervention of postoperative delirium in pediatric otolaryngology.Methods:By reviewing literature related to evaluation, prevention, intervention and management of postoperative delirium in pediatric otolaryngology from March 2018 to September 2019, fourteen best practice were concluded. By combining the best evidence and the clinical circumstances, the evidenced-based criteria were established and then applied in the Otolaryngology and Head and Neck Surgery Department, the Children ′s Hospital of Zhejiang University School of Medicine. Results:After three rounds of reviews, the results showed that the criteria 2, 3, 6, and 8 had 100.0% complacence. Comparison of before and after applying the evidence, there was no statistically significant difference for the occurrence of postoperative delirium or pain ( P>0.05); there was a statistically significant reduction of pain score at 60 minutes after returning to the ward ( χ2=9.93, P<0.05); there was a statistically significant reduction of preoperative anxiety score of children ′s family members from (33.36 ± 6.84) points to (29.54 ± 6.94) points ( F=6.33, P<0.05); there was a statistically significant increase of doctors ′ score of delirium knowledge based on evidence from (23.00 ± 3.94) points to (33.43 ± 8.25) points ( t=-3.02, P<0.05); and there was a statistically significant increase of nurses ′ score of delirium knowledge based on evidence from (33.11 ± 8.46) points to (57.79 ± 6.58) points ( t=-10.35, P<0.05) when the evidence was applied. Conclusion:The evidence-based practice didn ′t significantly relieve the postoperative delirium in pediatric otolaryngology, but it was helpful to relieve the postoperative pain level of children and the anxiety level of their families. The management of postoperative delirium in pediatric otolaryngology needs to be further explored.