Objective:To compare the shear bond strength of dentin to composite resin in different post-treatment time period after tooth bleaching with the TREE dental whitening gel and observe the dentin/composite interface of each group. Methods:Eighteen intact premolars were randomly divided into 3 groups(n=6):A:The specimens were immersed into artificial saliva for 3 weeks then adhesion without bleaching; B:Adhesion immediately after bleaching for 3 weeks,during bleaching the specimens were immersed into artificial saliva; C:Before adhesion the specimens immersed in artificial saliva for further 2 weeks after bleaching for 3 weeks. Five specimens from each group were randomly submitted to shear bond strength test. The specimen remained in each group were sectioned to be observed by the scanning electron microscope.Results:(1)The shear bond strength of the group B (10.74?3.03) MPa was significantly lower than that of the group A (18.61?3.56) MPa or the group C (17.21?3.15) MPa (P0.05); (2)The resin tags present in the dentin/composite interface was scarce for the group B,and that were shorter than the group A; The resin tags of the group A and group C were similar in number,but that of the group C was shorter than that of the group A. Conclusion:The use of TREE whitening gel immediately before bonding significantly reduces bond strength,but immersion of bleached teeth in artificial saliva for 2 weeks before bonding results in a return to control bond strength.

Objective To provide ideal endometriosis animal models for research new treatment methods. Methods 64 Sexual mature without pregnant SD rats who has regular oestrous cycle were underwent operation that autologous endometrium were transplanted to peritoneum and subcutaneous with lancet gently cut tissue of where to transplant in the rut, and compared the model of peritoneum and subcutaneous after 4 weeks.Results The general success rate of autologous endometrium transplantation in rat estrus was 93.3%,and the peritoneum transplantation success rate was 51.7%, subcutaneous was 88.3%, the difference of the two place transplantation has statistical significance. Compare the two parts of volume of endometriosis,there was no statistically significant difference.Conclusion Using the lancet to establish the endometriosis model has a high success rate, and subcutaneous model is better than peritoneum.

This article was aimed to study the chemical constituents of Dioscorea opposita Thunb.The chemical constituents were isolated and purified by Diaion HP-20,Toyopearl HW-40,Sephadex LH-20,MCI Gel CHP-20,silica gel column chromatography and preparative HPLC,TLC,purification and isolation from Dioscorea opposita Thunb.The structures of isolated compounds were identified by thc physicochemical properties and spectral analysis.The result showed that 14 compounds were isolated from Dioscorea opposita Thunb.The chemical structures were elucidated as L-Tryptophane (1),Seguinosides F (2),1-methoxycarbonyl-β-carboline (3),Helichrysin A (4),Bungein A (5),Hydroquinone (6),Zarzissine (7),Cyclo-(Pro-Thr) (8),4-Hydroxy-3-methoxybenzyl alcohol (9),pyridine-3-carboxamide (10),Arbutin (11),Methyl syringate 4-O-β-D-glucopyranoside (12),L-Phenylalanine (13),1,2-benzenedicarboxylic acid,1,2-bis[2-(2-hydroxyethoxy) ethyl] ester (14).It was concluded that chemical compounds 1-14 were isolated for the first time from Dioscorea opposita Thunb.

Objective: To analyze the microvessel density (MVD) and lymph node metastasis in the papillary thyroid carcinoma (PTC) with punctate or sheet calcification. Methods: Fifty PTC patients in the Affiliated Hospital of Yangzhou University from May 2015 to October 2017 were retrospectively enrolled in this study. All of the 50 PTC patients were divided into punctate calcification group (38 cases) and sheet calcification group (12 cases) according to the different features of pathological calcification in microscope examination. For the two groups, the central and peripheral zone MVD and the lymph node metastasis of each PTC nodule were compared. Results: For PTC nodules of punctate calcification group, the mean central and peripheral zone MVD were (51±7)/HP and (64±8)/HP, respectively. For those of sheet calcification group, which were (35±5)/HP and (49±6)/HP, respectively. The mean MVD in both central and peripheral zone of PTC nodules of punctate calcification group were significantly higher than those of the sheet calcification group (t values were 10.183 and 12.406, both P < 0.05). The neck Ⅵ area lymph node metastasis rates of the punctate and sheet calcification groups were 42.1% (16/38) and 8.3% (1/12), respectively. The lymph node metastasis rate of the punctate calcification group was significantly higher than that of the sheet calcification group (χ ² = 4.635, P < 0.05). Conclusion PTC nodules with different type of pathological calcification may have different invasion and metastasis, and PTC with punctate calcification is more likely to undergo local metastasis than PTC with sheet calcification.