Objective: To compare and analyze the maxillary lingual arch forms of ClassⅠmalocclusions after extraction and non-extraction treatment respectively. Methods: 60(30 with extraction, 30 non-extraction)maxillary dental models of ClassⅠmalocclusions after orthodontic treatment were measured in lingual arch widths and depths. The data were analyzed by statistical methods and the charts of lingual arch forms were drawn. Results: The lingual arch widths and depths in anterior segments of the extraction group were significantly larger than those of the non-extraction group(P0.05). The lingual arch forms of the two groups were similar in anterior segments, and more different in premolar and first molar segments, but similar from the distal lingual cusp of the first molars. Conclusion: The lingual arch forms of the two groups are similar in appearances, but the anterior segments of the extraction group are deeper than that of the non-extraction group.

Objective To study acute toxicity of nanometer titanium dioxide to the liver and kidney of mice. Methods 20 KM mice (22-26 g) were randomly divided into two groups, the control group and the experimental group, TiO2 (20-30 nm) suspension (single dose of 5 g/kg body weight) was given to mice by a single oral gavage, the mice in the control group were given the physiologicalsaline. 14 days after the treatment, the mice were sacrificed and the serum were collected to evaluate the levels of ALT(alanine amino transferase), AST(aspartate aminotransferase), ALP(alkaline phosphatase), UA(uric acid), Cr(creatinine),BUN(blood urea nitrogen), CK(creatine kinase), LDH(lactate-dehydrogenase), ?-HBDH(alpha-hydroxybutyrate dehydrogenase), TBIL(total bilirubin levels). The tissues of the liver and kidney were excised and were embedded in paraffin blocks, hematoxylin-eosin (HE) staining for further histopathological diagnosis. Results The serum ALT, ALT/AST, BUN, LDH and ?-HBDH of the TiO2 group were statistically higher than those in the control group (P

Objective To explore the feasibility and effectiveness of gradient elastic compression stockings in prevention of venous stasis in patients undergoing laparoscopic cholecystectomy(LC). Methods 160 LC patients were randomized into the experimental group(75 cases)and the control group (85 cases).Routine nursing care and treatment were performed in both groups,and gradient elastic compression stockings were used in the experimental group.Venous pressure was measured in four different periods (T1,T2,T3,T4). Results The venous pressure in T2,T3 and T4 in the experimental group was significantly lower than that in the control group. Conclusions Use of gradient elastic compression stockings is effective and feasible in preventing LC-induced venous stasis.

9 adults aged 23 to 43 years old were treated with bidimensional self-ligating lingual bracket technique for upper teeth and labial ceramic or aesthetic bracket for lower teeth.After treatment the labioclination of anterior teeth in Angle's II patients decreased from 28.12°± 10.05°to 19.25°±3.12°(P <0.05),in Angle's III patients from 32.14°±4.71°to 28.15°±3.26(P <0.05).

Objective:The effect of Tonglin capsule was observed on type steblay interstitial nephritis of cavy.Methods: The cavy was immunized using the basement membrane of renal tubule from renal cortex of rabbit and Freund's complete adjuvant (FCA). The animal model of autoimmunity renal tubule interstitial nephrifis was made, The effect of Tonglin capsule on nephric pathological changes was observed. Results: ① The levels of creatinine (Cr) and blood uria nitrogen (BUN) in treatment groups were obviously lower than that in model group ( P

Objective:To analyze the characteristics and differences of upper airway forms in the adults with class Ⅱ sagittal facial type of different vertical facial types and investigate the correlation between craniofacial structures and upper airway forms.Methods:Cephalograms of 135 adults with classⅡsagittal facial type of different vertical facial types were collected.60 cases were males and 75 cases were females.All the cephalograms were measured in sagittal upper airway depths.The differences were compared between genders,and also among different vertical facial type groups.Results:Among different vertical facial type groups,only the sagittal depths of nasopharynx(PNS-Ba、PNS-R)of the males and PNS-Ba of the females in high angle groups were smaller than that in average and low angle groups(P0.05),but the values of V-LPW of the males were larger than that of the famales in all vertical facial type groups(P

Objective: To investigate the effects and mechanism of microscrew implant anchorage (MIA) in speeding up the closure of extraction space by one step and retraction of anterior teeth. Methods: Twenty-three patients with teeth extraction and required strong posterior anchorage were treated with MIA to close the extraction space. The extraction spaces were closed by two methods respectively. The extraction spaces were closed by the method of one step and retraction of anterior teeth(Ni-Ti spring from MIA to the hook on the wire combined with the elastic pull from MIA to cuspid) on the experiment sides and by the traditional one step method(Ni-Ti spring from MIA to the hook on the wire alone) on the control sides. Which side treated as trial side or control side was selected at random. The period of the space closing, the way and position of anterior teeth movement were observed on each side and the period of the space closing of two sides were tested by paired t test. Results: ①The average period of the spaces closing which was (6.69±1.07) months on the trial side and (9.56±1.19) months on the control side was significantly different (P<0.05).② After the closure of extraction spaces, the cuspid achived better position on the trial side than the contral side on which cuspid presented distal-lingual rotation. Conclusion: The extraction spaces can be closed in all cases by two methods respectively. Using MIA to close the extraction space by one step and retraction of anterior teeth can not only shorten the period of space closing but also achieve nice outcome by moving the cuspid in spongy bone.

Objective To evaluate preventive effect of polysaccharides from Lycium ruthenicum Murray against photodamage in HaCaT cells,and to explore its possible mechanism.Methods Ultrasoundassisted extraction was used to extract polysaccharides from Lycium ruthenicum Murray in Qaidam Basin.In vitro cultured HaCaT cells were randomly divided into 3 groups:control group receiving no treatment,ultraviolet B (UVB) group irradiated with 30 nJ/cm2 UVB alone for 1 hour,experimental group pretreated with 2 g/L Lyeium ruthenicum polysaccharide solution followed 6 hours later by 30 mJ/cm2 UVB radiation for 1 hour.At twelve hours after UVB radiation,an inverted microscope was used to observe cell morphology.Then,MTS assay was performed to estimate cell proliferation,flow cytometry to detect cell apoptosis,an enzyme-labeled antigen method to detect levels of malondialdehyde (MDA) and glutathione peroxidase (GSH-Px),as well as to evaluate the activity of superoxide dismutase (SOD) and catalase (CAT),and enzyme-linked immunosorbent assay (ELISA) to measure levels of intedeukin-1 (IL-1) and tumor necrosis factor-alpha (TNF-α) in HaCaT cells and their culture supernatant.Results Compared with the control group,the UVB group showed obscure cell morphology,cell death and floating phenomenon,while cells became swollen but renained morphologically distinct in the experimental group.MTS assay revealed that the cell proliferative activity significantly differed among the above 3 groups (F =48.88,P ＜ 0.01),and the cell proliferative activity was significantly lower in the UVB group (1.72 ± 0.12) than in the control group (2.34 ± 0.11,P ＜ 0.05) and experimental group (2.11 ± 0.10,P ＜ 0.05).Moreover,the apoptosis rate was significantly higher in the UVB group (82.41％ ± 2.49％) than in the control group (3.98％ ± 0.19％,P ＜ 0.05) and experimental group (22.79％ ± 0.97％,P ＜ 0.05),as well as higher in the experimental group than in the control group (P ＜ 0.05).Compared with the control group,the UVB group showed significantly higher levels of MDA,supernatant levels of IL-1 and TNF-α,and intracellular levels of TNF-α,but significantly lower GSH-Px levels and activity of SOl and CAT (all P ＜ 0.05).However,there was no signifi-cant difference in the intracellular level of TNF-α between the UVB group and control group (P ＞ 0.05).Conclusion Lycium ruthenicum polysaccharide has protective effects against photodamage in HaCaT cells,likely by reducing the synthesis and secretion of inflammatory substances as well as free radicals.