Objective:To observe the changes of c-jun expression in the monkey's temporalis muscles induced by stress reaction under +Gx loads.Methods:Nine male Rhesus macaques were randomly divided into four groups according to Gx loads and its lasting time:control group was exposed to +1 Gx/300 s overloads(n=2),and experimental groups 1(n=2),2(n=2)and 3(n=3)were exposed to +15 Gx/200 s,+21 Gx/165 s or +21 Gx/140 s respectively.Temporalis muscles tissue was fixed with 40 g/L buffered formaldehyde and embedded in paraffin.Histopathological changes were observed under light microscope.The expression of c-jun was detected by immunohistochemical PicTureTM method in the temporalis muscles.Results:Gross and histological analyses showed that no significant pathological changes in the temporalis muscles in different experimental groups.Immunohistochemical staining demonstrated that c-jun was over-expressed in the nuclei of the muscles in the experimental groups,while negative or slight positive staining was observed in the nuclei of muscles in control animals.There was no obvious difference of c-jun expression in different experimental groups.Conclusion:Overload gravity can induce enhanced expression of c-jun in temporalis muscles of the monkeys received +Gx loads.

The main physiological function of respiratory system is exchange of oxygen and carbon dioxide between atmosphere and blood. Its physiological process is closely related with air flow and transport in respiratory airway. This paper studies numerically the inspiratory flows in a two generation and a three generation bronchial airway. The numerical results of the two generation bronchi show that the present computations fit the available experiments very well. For three generation bronchi, no separation appears within the whole airway under normal breathing rate, which is contrary to the occurrence of separation at even low Reynolds number by the previous two dimensional models. Strong secondary flow phenomenon, skew and m-shaped main flow velocity profiles are found in the airways due to geometrical curvature and bifurcation. These increase shear stress acting on the inner wall as well as on the anterior and posterior wall in the bifurcating airways. In the end bronchi of the three generation airway, the mass flow rates in medial and lateral bronchi are unequal, and the mass flow ratio between the medial and the lateral bronchi is 1.2 at the flow conditions considered.
Bronchi ; anatomy & histology ; physiology ; Finite Element Analysis ; Humans ; Inhalation ; physiology ; Models, Biological

Objective:To investigate the relationship between pulp chamber height and dentine thickness of mandibular first molar on long axis with age in a Chinese Han population by cone-beam computed tomography(CBCT).Methods:CBCT images of 420 Chinese Han subjects(210 males and 210 females) were divided into 6 age groups as follows:15-24,25-34,35-44,45-54,55-64 and 65-74 years(n=70,35 males and 35 females).The height of pulp chamber and dentine thickness of the chamber root and floor of mandibular first permanent molar on long axis was measured by Galileo software of CBCT in vertical direction and then statistical analysis was carried out.Results:On long axis,the height of pulp chamber was (0.85±0.54) mm in males and (0.79±0.51) mm in females(P>0.05);dentine thickness of the pulp chamber roof was (3.60±0.49) mm in males and (3.50±0.49) mm in females(P>0.05);and dentine thickness of the pulp chamber floor was (2.57±0.52) mm in males and (2.49±0.5) mm in females(P>0.05).With aging,the height of pulp chamber was decreased(P<0.05) and dentine thickness of mandibular first permanent molar on long axis was increased(P<0.05).Conclusion:In Chinese Han population,the of pulp chamber height of mandibular first permanent molar on long axis is related to age,The dentine thickness increased with ages,the increase of dentine thickness of pulp chamber floor is more significant than that of the roof.