Evidence-based medicine (EBM) has rapidly developed in recent years and is currently a hotspot in international medicine. The guiding principle behind EBM is that any medical decision should be determined based on objective clinical and scientific evidence, doctor's professional skills and experience, and patient's needs and desires. This paper introduces the concept and practice of EBM and explains how it can be used to solve the issues in stomatology.
Evidence-Based Medicine ; Humans ; Oral Medicine

Objective:To evaluate the effectiveness and treatment feature of maxillary incisor extraction in orthodontics.Methods:9 patients underwent orthodontic treatment with maxillary incisor extraction,5 female and 4 male,with an average age of 1 7.2 years at the start,were included.5 patients were treated by extraction of both upper incisors and lower first premolars,4 by extraction of the abnor-mal incisor and the first premolars in the other three quadrants.Cephalometric and Bolton index analysis were carried out.Results:Sat-isfactory treatment results were observed in all patients.Before treatment the predicted Bolton index of the patients of the anterior ratio and the overall ratio were 80.1 4% and 91 .3%,after orthodontic treatment 78.68% and 90.28%,respectively.Cephalometric analysis showed that U1 -NA(mm),U1 -NA,L1 -NB(mm),L1 -NB,U1 -SN,L1 -MP,UL-E and LL-E were decreased(P <0.05).Conclu-sion:Individual treatment plan based on Bolton index analysis and the corresponding techniques and methods,the patients with abnor-mal upper incisors can be effectively treated with the extraction of maxillary incisors.

It is a trend that clinical researchers overemphasize on hypothesis testing and the P value. However, P value has some limitations in the presentation of study results. Power is a tool for study design and results explanation, especially for negative results. Confidence interval contains more information for clinical results than P value. P value, power, and 95% confidence interval should be provided in the clinical reports to facilitate the interpretation of the results.

Objective To study the mechanisms of increasing amyloid [β1-42 (Aβ42) level by presenilin-1 (PS-1) mutation of V97L.Methods Expression level of neprilysin (NEP) in nontransfected, or mock vector, wild type (wt) PS-1 and V97L-PS-1-transfected SH-SY5Y cells were assessed by reverse transcriptional-polymerase chain reaction (RT-PCR) and Western blot.The level of Aβ42 was also assessed by enzyme linked immunosorbent assay (ELISA).Results The mRNA level of NEP was decreased significantly in PS-1 V97L transfected cells (0.650 ± 0.010) compared to that in normal cells (1.090 ± 0.015), wt PS-1 gene (1.040 ± 0.021) and mock (1.080 ± 0.020) stably transfected cell lines (t = 9.236, 10.452, 5.678; all P < 0.01).Although there was a decreased tendency in the protein expression of NEP in PS-Ⅰ V97L transfected cells (1.000 ± 0.126)compared to that in normal cells (1.020 ± 0.110), wt PS-1 gene (1.040 ±0.110), mock (2.130 ±0.130) stably transfected cell lines, nosignificant differences were found.The expression of Aβ42 was increased significantly in PS-1 V97L transfected cells compared to other cell lines (t = 2.109, 3.355, 3.976; all P < 0.01).Conclusions PS-1 V97L mutation can decrease the transcription of NEP, however, in contrast, this mutation also resulted in increased Aβ42.The mechanism needs further analysis.

Objective To study the effect of lovastatin on the expression and activity of β-site APP cleaving enzyme (BACE1). Methods The SH-SY5Y cells were treated by lovastatin. Cell viability was assessed by MTT assay, and the levels of cholesterol were assayed spectrophotometrically, and the activity of BACE1 was detected by fluorometric assay, and the expression level of BACE1 was detected by Western Blot. Results Compared with the control group, the cholesterol levels were decreased by 33.0% (3.33 vs. 4.97; F=5.13, P =0.020) and the activity of BACE1 was reduced by 13.8% (343.14 vs. 398.22; F=3.773, P =0.035) after 24h treatment of 5μmol/L lovastatin; the cholesterol levels were decreased by 49.2% (2.65 vs. 5.22; F=12.239, P =0.001) and the activity of BACE1 was reduced by 38.0% (274.75 vs. 443.14; F=13.610, P <0.01). Treatment with 5μmol/L lovastatin,for 48 h did affect the expression level of BACE1. Conclusions Lovastatin do not affect the expression level of BACE1, but may inhibit its activity and decrease the cholesterol level, thus providing a new approach to prevent or treat Alzheimer's disease (AD).

Objective To investigate the relation between expression of P73 , P53, P21 waf1 ,PCNA protein in the different diseases of gastric mucosa and the malignant transformation of gastric mucosa epithelium and their correlation in gastric carcinoma and the relation to histological type , lymph node metastases, depth of invasion of gastric mucosa ,TNM stage in gastric carcinoma. Methods Immunohistochemical staining(S-P method) was used to detect the expression of P73, P53, P21 waf1 , PCNA protein in 39 cases of gastric carcinoma, 17 cases of chronic atrophic gastritis and 40 cases of chronic inflammatory polyp and a statistical analysis was made according to clinicopathogical data. Results The positive rate of P73 protein expression in gastric carcinoma was remarkably higher than that in chronic inflammatory polyp and that in chronic atrophic gastritis( P 0.05). there was negative correlation between expression of P21 waf1 protein and TNM stage, lymph node metastases( P 0.05). Conclusion Probably high expression of P73 gene is one hot spot gene alteration of gastric carcinoma and expression of P73 protein in gastric carcinoma may play an important role in the course of cancerous development. As one tumor suppressor gene, P73 has its tissular specificity. Cooperative expression of P73 and PCNA,and the correlation of expression to P73 and P53 、P21 waf1 protein could be an important index to judge the malignant transformation and clinicopathological process and prognosis. P21 waf1 may be an early signal of gastric carcinoma or one of indexes to judge prognosis.

Objective To study effects of Ginsenoside Rg1,Rb1 on activity and genetic expression of alpha secretase in the progress of metabolism of APP.Methods Chinese hamster ovary (CHO) cell line transacted by mutant PS1 (ML46L) genes and wild type PS1 genes was used.The activity of alpha secretase was tested by fluorometric reaction.The expression of ADAM9 and ADAM10 was analysis through western blotting and RT-PCR.Results The activity of alpha secretase was increased significantly in Ginsenoside Rg1,Rb1 group than that without Ginsenoside group (P

Dendritic cells act as the major antigen presenting cells in the body and play a central role in intri-guing the adaptive immune response. Protective immunity against schistosome and immuno-pathological response in host caused by eggs are both closely associated with Th2 response. Further understanding on immune mechanism will contribute to the development of vaccines against schistosome infection, as well as the relief of the pathological lesion in schistosomiasis. This article discusses the central role of dendritic cells in the mechanism of Th2 response induced by schistosome (including eggs).

Objective To investigate the effect and mechanism of Jinkuishenqi wan (JGSQ) on pulmonary fibrosis. Methods Pulmonary fibrosis was induced by bleomycinA5 in SD rats. Rats in treatment group were killed after being treated by JGSQ daily for 28 days. The lungs of all rats were harvested for histopathological studies. The contents of transforming growth factor-?_1 (TGF-?_1) in lungs were measured and compared. Results The contents of TGF-?_1 in lungs increased significantly in model group as compared with normal group and treatment group (P

OBJECTIVE To study the risk factors of pulmonary infection and prognosis in cerebral apoplectic patients.METHODS A retrospective survey on 497 cerebral apoplectic patients was analyzed to investigate the rate of pulmonary infection,the type and the severity of cerebral apoplexy,the underlying disease,the age,and the prognosis.RESULTS The rate of infection highly increased in the older patients with the severe diseases and many riskfactors.CONCLUSIONS Controlling the rate of pulmonary infection can help us to succeed in treating cerebral apoplexy.