Hypoxic microenvironment is a typical characteristic of solid tumors and is considered an independent risk factor in tu-mor progression and poor prognosis. Hypoxic microenvironment is a critical part of cancer stem cell (CSC) niche and plays an impor-tant role in the evolution of cancer stem cells in tumors and in apoptosis resistance. As a key factor in the tumor's adaption to hypoxic microenvironment, hypoxia inducible factors (HIFs) can induce biological behavioral changes in CSCs that can accelerate tumor malig-nant transformation. Such behavioral changes include anti-apoptosis, enhancement of drug-resistance gene expression, and tumor inva-sion and metastasis. HIFs are also among the main factors affecting the capacity of CSCs to maintain their biological characteristics. In this review, the authors focus on recent advances in our understanding of the role that HIFs play in maintaining the biological character-istics of CSCs.

Objective: To observe the effects of acid etching times on nano-leakage and microtensile bond strength(?TBS) of the 4 total-etching adhesives-dentin bond.Methods: Superficial occlusal dentin surfaces of 80 molars were prepared with 600-grit SiC paper under running water.4 adhesives were applied to dentin surfaces under different etching time.The bonded teeth were sectioned occluso-gingivally into 1.0 mm?1.0 mm?4.0 mm serial slabs which were prepared for TEM and ?TBS tests.Results: Under 15 s etching time for 4 adhesives,the highest ?TBS(OB(25.36?4.18) MPa,SB(24.25?3.97) MPa,OS(28.65?4.93) MPa,PB(27.12?4.13) MPa) were achieved,and the amount of nanoleakage was positively correlated with the length of etching time.Conclusion: Etching for a reasonable time demineralizes the dentin surface to a moderate depth,resulting in higher ?TBS and lower nanoleakage.

Objetives: To evaluate the microtensile bond strengths o f four dentin adhesives (Single Bond, Bond-1, Prime&Bond NT and One-Step) i n vivo.Methods: Before extraction the superficial occlu sal dentin of 19 molars (because of severe periodontitis) in 17 volunteers was exposed by diamond bur of a high-speed hand-piece copious air-water spray under local anesthesia, the crown was bonded with one of the above adhesives a ccording to the manufacturers' instructions. The teeth were then extracted and kept in normal saline for 24 h under 37 ℃,sectioned to obtain two or three bar -shaped specimens, which were then shaped to an hour-glass form. The specimens were stressed until rupture of the bond. The mean bond strength of the adhesive s was measured and compared using student test. Rusults: M ean microtensile bond strength (MPa) of Single Bond,Bond-1,One-Step and Prime & Bond NT to the tooth surface was 26.18?3.67,30.08?3.15,29.91?3.51,29.70?3 .03 respectively (P

Objective To identify the factors related to the influence of medical research papers. Methods The influence of 1146 research papers by the hospital in the period 1996-2003 and its relationship with such factors as the backgrounds of the authors and the quality of the papers were studied u-sing regression analysis. Results Nine factors, including the impact factor, the status of the paper (being or not being one based on fund-supported research or representing research achievements), and the status of the author (being or not being chosen for talent cultivation and undertaking or not undertaking research projects), were significantly correlated with the influence of the papers. Conclusion In order to enhance the influence of medical research papers, it is necessary for research' management departments not only to encourage research personnel to publish papers in journals with high impact factors but also to step up efforts to better personnel cultivation, degree education, and project and achievement management so as to set up a quality and distinguished research contingent.

0.05), the FADRHPC could save a great amount of time and worked automatically. Conclusion: The FADRHPC can simplify manipulation processes and make satisfied dentures.

Objective To summarize the progresses made domestically and abroad and the developmental tendency of stomatology,and to propose the orientation of development in stomatology in China. Methods The latest progresses and developmental tendency in the field of stomatology were achieved by investigating related references,reviews,research reports and treatises published in recent 10 years. Results In recent years,the increasing integration of stomatology,comprehensive medicine,biomedical engineering,and tissue engineering facilitated the development of stomatology towards digitization,minimal invasion,functionalization and customization,which has made great achievements in basic researches and clinical techniques of stomatology in the armed forces. Conclusions It is the key period of the Twelfth Five-Year Plan for the development of the stomatology in the armed forces. Servicing the basic level of the troop,promoting dominant subjects,improving weak components of the discipline,and comprehensively promoting the internationalization should be insisted in driving innovations of stomatology in the armed forces.

Objectives: To evaluate the effect of thickness and opaque resin on the light transmittance of Artglass. Methods: Samples of Artglass prepared in the thickness(mm) of 0.50,0.75,1.00,1.25,1.50,1.75 and 2.00 with or without opaque resin respectively.The light transmittance of the specimens was measured. The color values of the specimens on the CIE L*a*b* color system were determined by a digital chroma meter. Results: The light transmittance of Artglass decreased logarithmically with the increase of the thickness (R2=0.9834 in the group of samples without opaque and R2=0.9390 in those with opaque). The light transmittance of Artglass with opaque resin was lower than that without opaque resin. Conclusion: Thickness and opaque resin have significant effect on the light transmittance of Artglass.

ObjectiveTo describe self efficacy,pregnancy pressure and serum cortisol levels during late pregnancy period in primiparas and explore the mediating effects and regulating effects of self efficacy between pregnancy pressure and serum cortisol levels. MethodsBy convenient sampling,General Selfefficacy Scale and Pregnancy Pressure Scale were conducted to estimate the self-efficacy and pregnancy pressure in primiparas.Maternal venous blood was collected to measure cortisol levels. ResultsThe selfefficacy was positively related to pregnancy pressure and cortisol levels.Self-efficacy has acted partial mediating effects and regulating effects between pregnancy pressure and cortisol levels in primiparas,the mediating effect to the total effect was about 32.6％. ConclusionsSelf-efficacy has acted partial mediating effects and regulating effects between pregnancy pressure and cortisol levels in primiparas.

Objective To evaluate the influence factor of 'SF-FDG and 18F-FLT PET/CT for diagnosing pulmonary nodules.Methods 55 patients with pulmonary nodules were chosen as study target,include 33 male cases and 22 female cases,the age range from 17 to 82 years old.In all cases,28 cases had one pulmonary nodule,others had 2 or 3 pulmonary nodules,and the nodule size was 0.6-11.0 cm.18F-FDG and 18F-FLT PET/CT were performed on 55 patients.The relationship of SUV of 18F-FDG and 18F-FLT with sex,age,size and pathology of all pulmonary nodule patients were analyzed.Results The SUV of 18F-FDG and 18F-FLT had no statistics difference on sex,age and size(P>0.05),the SUV of 18F-FDG had no statistics difference on pathology of pulmonary nodule(P>0.05).Otherwise,the SUV of 18F-FLT had statistics difference on pathology of pulmonary nodule(P<0.05).Conclusion The pathology of pulmonary nodule was an important influence factor for SUV of 18F-FLT,and the ~SF-FLT PET/CT has the high diagnostic effectiveness for pulmonary nodules and this method will has great influence on the clinical management of pulmonary nodule patients.

Objective:To introduce a new fixation set-up for micro-tensile test.Methods:Dentin-composite were bonded with AdperTM Single Bond 2 (SB2)and sectioned into stick-shaped specimens.Specimens from each tooth(n =6)were equally divided into Ciucchi's jig and the designed set-up(Control and experimental)groups for micro-tensile bond test according to the utilized fixa-tion set-up.The bonding interface failure mode was examined with field-emission scanning electron microscope (FESEM).Three-dimensional models of the two set-ups and the specimen were developed,stress distribution was analyzed by finite element analysis (FEA).Results:The bond strength(MPa)of experimental and control group was 32.76 ±7.43 and 43.58 ±4.72(P <0.05),the ratio of mixed failure was 28 /36 and 20 /36(P <0.05)respectively.FEA showed that the designed set-up for fixing the sticks pro-vided a uniform stress distribution along the long axis of the specimen.FEA and failure mode analysis confirmed such uniform distri-bution was also concentrated at the bonding interface.Conclusion:The new set-up is feasible for micro-tensile test.