Dental impressions are widely used in the field of oral restoration. The materials are used for making impression in oral cavity. In order to measure the thickness of impression for reference in clinic, the real impressions are taken as the object for studying. Through optical method, charge-coupled device (CCD) is used for collecting the grey image of cutting section of the impressions which are located in the same plane with steel dividing ruler. According to convert relationship between dividing ruler and pixels collecting grey image, the thickness of impression specimens can be obtained. The results show that the optical method used for measuring thickness is feasible to the task and the precision can reach micro dimension. The experiment method and technique can also be provided for measuring thickness of similar tissue engineering materials.
Dental Impression Materials ; Dental Models ; Humans ; Materials Testing ; Optics and Photonics

BACKGROUND: It is believed that repetitive transcranial magnetic stimulation (rTMS) may produce such neurophysiological effects as regulating regional cerebral blood flow, neurotransmitters, local metabolism, and neuronal remodeling after nerve tissue injuries. The prognosis ofischemic stroke is related with the cortical function reconstruction in the ipsilateral and contralateral hemisphere of the lesion. Currently studies have not defined whether rTMS can affect the cortical function, protect ischemic neurons and promote motor functional recovery after cerebral ischemia.OBJECTIVE: To investigate the effects of rTMS on rat motor cortical excitability and neural function in acute stage of cerebral ischemia-reperfusion injury.DESIGN: Completely randomized experiment.SETTING: Electroneurophysiological Laboratory of Peking Union Medical College Hospital.MATERIALS: The experiment was completed in the Zoological Research Center of Peking Union Hospital from January to June 2004. Totally 22adult male healthy Wistar rats were randomly divided into treatment group and the control group with 11 in each.METHODS: After determination of the average motor threshold of the right hind limbs, which was 22% of the maximum output, the rats were subjected to middle cerebral artery occlusion for 1 hour followed by reperfusion for 72 hours. At each time point of immediately and at 12, 36 and 60 hours after the initiation of reperfusion, the rats in the treatment group received rTMS treatment (20 Hz, 40% maximum output, 5 seconds for each session with an between-session interval of 2 minutes for a total of 10 sessions), and the site for motor threshold evaluation was used for rTMS stimulation; the rats in the control group recevied no treatment after model establishment. Motor threshold testing was performed in both groups 4 hours after the last session of treatment to avoid immediate-early effects of rTMS on the motor threshold. At 24 and 72 hours of reperfusion, the scores of neural function were recorded according to evaluation systems. All the rats with scores between 1 and 3 were enrolled in statistical analysis were evaluated between.MAIN OUTCOME MEASURES: ① Motor threshold of the rats in both groups before and after injury; ② Neural function scores at 24 and 72 hour reperfusion; ③ Infarct volume at 72 hour of reperfusion.RESULTS: Totally 13 rats entered the final result analysis. Before injury,motor threshold in the treatment and control group was similar (P=0.71),and after the injury, the motor threshold of the control group was 1.49times that of the treatment group but such difference was not statistically significant [(41.62±24.73)% vs (28.00±9.35)%, t=-1.17, P=0.27]. At 24hours of reperfusion, the functional scores of the treatment group and control group were not significantly different (P=0.46), but at 72 hours, the scores of the treatment group were significantly lower than that of the control group (1.60±1.52 vs 7.75±3.62, t=-3.57, P=0.004). The average infarct volume of two groups was (62.00±60.88) mm3 and (20.00±12.41) mm3 at 72 hours of reperfusion, respectively, which, after logarithm transformation,was not significantly different between the two group (t=-1.31, P=0.22),but when the infarct volume was transformed into Log10 values, a significant difference occurred between them (P=0.045).CONCLUSION: rTMS may stabilize and prevent the increment of the motor threshold, time-dependently relieve the neural function disability and reduce the infarct volume after cerebral ischemia-reperfusion injury.

Purpose To explore the clinicopathological features,immunophenotype,differential diagnosis and prognosis of the composite pheochromocytoma (CP)-ganglioneuroma.Methods 3 cases of CP-ganglioneuroma were stained by immunohistochemical SP method,and the related literatures were reviewed.Results 3 cases of CP-ganglioneuroma were one male and 2 females,the age were 37-64.Case 3 were of primary mediastinal.Microscopically,the tumor tissues were composed of two components:one type of tumor cells were arranged in nests with a predominant Zellballen pattern,round or oval nuclei,fine granular cytoplasm and rare mitotic,another part of the neoplasm showed scattered and aggregated distributed ganglion cells in the background of neurofibromatosis which aligned bundles and interwoven,the edge of the tumor was still residual adrenal tissue.Immunohistochemically,components of pheochromocytoma were positive for CD56,CgA,Syn,vimentin and negative for SMA,Melan-A,α-inhibin NF with low Ki-67 proliferation index.S-100 was positive in supporting cells,ganglioneuroma components were positive for NF,S-100 with low Ki-67 proliferation index.CgA and Syn were weakly positive or negative in the ganglion cells.Conclusion CP is a relatively rare tumor,which can not be distinguished from pheochromocytoma in clinical and radiological diagnosis.The corresponding clinical treatment and follow-up management should be taken according to the different ingredients (benign or malignant).

Objective To evaluate the clinical value of MSCT in the diagnosis of unexplained aseites.Methods 113 patients with unexplained ascites were retrospectively reviewed by CT、clinical data and continous observation.Results Large ascites in 50 cases(44.3%),moderate amount aseites in 10 cases(8.8%),small ascites in 53 cases(46.9%);Parietal peritoneum changed in 51 cases(45.1%);Mesentery changed in 44 cases(38.9%);Grerter omentum changed in 20 eases(17.7%);Enlargement of lymph nodes in 67 cases(59.3%).Conclusion Malignant tumor was the most common cause of unexplained ascites.MSCT could help in identifying tumors and the tumor lesion,forecast malignant ascites,and had great value in etiology and diagnosis of ascites.

Objective To investigate the diagnosis of a case with 7p15.3p22.1 microdeletion by applying array-based comparative genomic hybridization (array-CGH) and to analyze the relationship between the clinical manifestations and 7p15.3p22.1 microdeletion. Method Array-CGH technique was used to detect genomic copy number variations (CNVs) in an infant with normal karyotype after conventional chromosomal karyotyping. Results Array-CGH detected 7p15.3p22.1 deletion (chr7: 6777262-23981753), which was confirmed as pathogenic CNV after comparative analysis with database. Conclusion Array-CGH could serve as a useful complement for G-banding to be used in the clinical cytogenetic diagnosis.

AIM: To investigate the protective effect of onychin on the endothelial cells injured by oxidative stress. METHODS: The injured model was established by endothelial cells treated with menadione. The growth inhibitory rate of endothelial cell was determined by MTT assay; NO - 2/NO - 3 concentration in the medium was determined by nitrate reductase assay; eNOS and caveolin-1 protein levels were determined by Western blot. RESULTS: Onychin significantly decreased the growth inhibitory rate of endothelial cells injured by menadione, increased NO - 2/NO - 3 concentration in the medium and eNOS activity and up-regulated caveolin-1 expression. CONCLUSION: Onychin possesses a protective effect against endothelial cell injury induced by menadione via caveolin-1/eNOS pathway.

AIM: To explore the cytokines level and the discrepancy of reaction to dexamethasone (Dex) in ALI rats induced by hydrochloric acid (HCl) and lipopolysaccharide (LPS). METHODS: Ninety-six SD rats were divided into six groups at random (n=16 in each group): NS group, HCl group, LPS group, NS+Dex group, HCl+Dex group and LPS+Dex group. Every group was divided into two subgroups: the bronchoalveolar lavage (BAL) subgroup and no bronchoalveolar lavage (NBAL) subgroup. The total leukocytes, PMN%, macrophage%, lymphocyte%, total protein in BALF and the wet/dry of the lung weight were measured. The concentrations of TNF-?, IL-1?, IL-4 and IL-10 in serum and BALF in every group were compared. RESULTS: (1) In the groups of LPS and HCl, the total leukocytes, PMN numbers, the protein concentration in the BALF and W/D were higher than those in control group (P

Objective To investigate the diagnostic value of the instant gastrointestinal ultrasound contrast agent in the digestive diseases. Methods Five hundred and seventy-nine patients received the examination of the color Doppler after they drinked the ultrasonic contrast agent. Then the results were analyzed by consistency analysis. Results There was high consistency between the two examinations in the normal control, gastritis, peptic ulcer, gastric cancer and gastric leiomyoma. The Kappa value was 0.768, 0.913, 0.925, 0.939 and 1.000, respectively. But the consistency in the gastric polyp was low , the Kappa value was 0.368. Conclusion The color Doppler through the instant gastrointestinal ultrasound contrast agent has high diagnostic value in the common diseases of the digestive system.

Objective To compare and analyze the clinical characteristics of acute central cervical spinal cord injury with only upper extremity involvement and with both upper and lower extremity involvement.Methods A retrospective case control study was made on clinical data of 76 patients with acute central cervical spinal cord injury hospitalized from January 2010 to December 2013.Nerve injury involved was only upper extremity in 39 patients (upper extremity group),but both upper and lower extremities in 37 patients (upper-and lower-extremity group).In upper extremity group,there were 35 males and four females,age was 21-80 years [(52.5 ± 13.4) years],injury resulted from traffic accidents in 24 patients,ground-level falls in eight,high-level falls in six and heavy-object hit in one,and level of injury was C3/4 in 16 patients,C4/5 in 14 and C5/6 in nine.In upper-and lower-extremity group,there were 30 males and seven females,age was 36-78 years [(59.6 ± 9.7) years],injury resulted from traffic accidents in 16 patients,ground-level falls in 11,high-level falls in seven and heavyobject hit in three,and level of injury was C3/4in nine patients,C4/sin 18 and C5/6in 10.Sagittal diameter of the cervical spinal canal,maximal canal compromise,maximal spinal cord compression,degenerating factors of the cervical spine and treatment protocols were determined.Upper extremity function was assessed with the American spinal injury association (ASIA) score.Results There were significant differences between upper extremity group and upper-and lower-extremity group in sagittal diameter of the cervical spinal canal [(7.5 ± 1.5)mm ∶ (6.8 ± 1.2)mm],maximal canal compromise [(28.9 ±9.6)％ ∶ (34.9 ± 10.6)％],ASIA score at admission[(31.6 ± 11.8)points ∶ (22.7± 11.3)points)] and ASIA score at last follow-up [(46.2 ± 4.2) points ∶ (40.2 ± 4.0) points] (P ＜ 0.05),while the maximal spinal cord compression in upper extremity group [(15.7 ± 11.9)％] had no significant difference from that in upper-and lowerextremity group [(17.0 ± 10.6) ％] (P ＞ 0.05).Lower prevalence of posterior osteophyte of the vertebral body was noted in upper extremity group than upper-and lower-extremity group (15％ ∶ 51％) (P ＜0.01).Twenty patients (49％) in upper extremity group were surgically treated,while 31 patients (84％) in upperand lower-extremity group (P ＜ 0.05).Conclusions Compared to acute central cervical spinal cord injury with both upper and lower extremity involvement,the injury with only upper extremity involvement is much common in younger patients and is characterized by lowered frequency of osteophyte,large buffer space,mild nerve damage,preferred non-operation treatment and good prognosis.

Objective To investigate the application value of ELISA for detecting the serum anti desmoglein (Dsg) 1 and Dsg 3 in the diagnosis and treatment of pemphigus .Methods Forty‐seven patients with pemphigus in our hospital from January to De‐cember 2014 were selected as the observation group and contemporaneous 52 patients with excluding pemphigus were selected as the control group .The Dsg antibodies were detected by using indirect immunofluorescence method and Dsg 1 and Dsg3 were deter‐mined by ELISA ;their correlation with pemphigus characteristics was analyzed .Results The sensitivity and specificity of ELISA for detecting anti‐Dsg antibodies were 95 .74% and 92 .31% respectively ,while which of IIF were 93 .62% and 86 .54% respective‐ly ,showing no statistically significant difference between the two test methods (P>0 .05) .In 30 cases of pemphigus vulgaris ,16 ca‐ses (16/30) were positive Dsg1 and Dsg 3 ,8 cases of pemphigus erythematosus and 5 cases pemphigus foliaceus were positive Dsg1 only ,and 2 cases of pemphigus vegetans were both positive Dsgl and Dsg3 .The Dsgl and Dsg3 titers of pemphigus vulgaris and pemphigus vegetans were 130 .85 ± 86 and 112 .30 ± 85 .05 ,respectively ,and the disease activity score was (5 .10 ± 1 .86) points ,the correlation coefficient(r)=0 .476(P=0 .008) ,r=0 .816(P=0 .001) ,respectively .The Dsgl titer of pemphigus erythematosus and pemphigus foliaceus were 142 .59 ± 78 .52 ,and the disease activity score was (2 .77 ± 0 .92) points(r=0 .800 ,P=0 .001) .Conclu‐sion ELISA for detecting Dsg1 and Dsg3 has high sensitivity and specificity ,and is conducive to the diagnosis of pemphigus and e‐valuation of disease severity .