7.Tooth development in vitro cultured mouse mandibular arch
Shisen LIU ; Buling WU ; Qing YU
Journal of Practical Stomatology 2001;0(03):-
Objective:To establish a model for the study of tooth initiation and early development by in vitro culture of mouse mandibular arch . Methods:42 mandibular arches of 11dpc fatal mouse were dissected and cultured in Trowell organ culture system for 11 days.Regular histologic observation was performed to observe the initiation and development of tooth.Results: Mandibular arches grew well in Trowell culture system.The initiation and early development of tooth was found.The explants maintained to cap stage.On day 11,necrosis of the cultured mandibular arches was observed and the culture was ended. Conclusion:In vitro cultured mandibular arch can be used as a model for the study of tooth initiation and early development.
8.Expression of NF-kB during the replacement of primary and permanent teeth in dog
Journal of Practical Stomatology 1995;0(04):-
Objective:To observe the expression of nuclear factor kappa B(NF-kB) during the replacement of primary and permanent teeth in dog. Methods:By immunohistochemistry, expression of NF-kB was examined in the tissues around deciduous tooth root at resorption stage in 2 dogs aged 3-4 months.Results:NF-kB positive signals were observed in the osteoclasts up to the permanent tooth germ and in odontoclasts in the medial wall of the pulp cavity of deciduous teeth.Conlusion:NF-kB may involve in the eruption of permanent teeth during the stage of the replacement of primary and permanent teeth.
9.Guideline for technique of coronary artery bypass.
Qing-yu WU ; Jian-ping XU ; Chang-qing GAO
Chinese Journal of Surgery 2006;44(22):1517-1524
10.A biomechanical research into different internal fixations for ACL avulsion fractures of tibial eminence
Yu-Feng WU ; Pei-Ji SU ; Zhong-Qing WU ;
Chinese Journal of Orthopaedic Trauma 2004;0(09):-
Objective To conduct a hiomechanical comparison of the four common internal fixation methods for the anterior eruciate ligament(ACL)avulsion fractures of displaced tibial eminence.Methods Sixteen fresh cadaver knee joints were used and randomized into four equal groups of four fixation methods:antegrade wiring group, retrograde wiring group,suturation group,and intramedullary screw group.The knee joint specimens were fixed at flexion of 30?and subject to continuous stretch stresses of 30 N,60 N and 90 N respectively on a material testing machine(MTS 858 Bionix test system,USA)which conducted a simulated Lachman test.The specimens were scanned at different angles by a three dimensional laser scanner.Data were recorded and processed by image software to es- tablish three-dimensional structure models of femur,tibia and knee joint.The test results were analyzed statistically on a computer.Results There were no obvious differences between each fixation group in the length change of ACL when the stresses were 30 N and 60 N(P>0.05).Under 90 N stress,however,the mean length change between the femoral and tibial attachments of ACL was the smallest(4.8?1.7)mm(2.5 to 6.2 mm)in the suturation group(P<0.05). There were no distinct differences between the intramedullary screw group and the retrograde wiring group in the changes of A CL shift(P=0.214).The average front shift in the retrograde wiring group was(6.2?1.2)mm(4.8 to 8.2 mm) and significantly smaller than that in the antegrade wiring group(P<0.05).The antegrade wiring group made the largest average front shift under different stresses and its average front shift was(7.2?1.3)mm(5.6 to 8.7 mm). Conclusions The knee joint stability provided by the suturation fixation is distinctly better than that by the other three fixation methods.The antegrade wire fixation provides the poorest knee joint stability.There is hardly any difference between intramedullary screw fixation and retrograde wiring fixation.