Objective To observe the research of the biologically performance,interface micro-structure and nano-indentation situation when polymethyl methacrylate bone cement-PMMA injected into rabbit in the near future and far future individually.Methods New Zealand white rabbits were used ovariectomy plus dcxamethasone intramuscular injection to establish osteoporosis animal model.All animal models were divided into 3 groups with 35 in each osteoporosis group,testing group,and normal group.Execute the lumbar centrum of New Zealand rabbit as osteoporosis bone defect model,injected bone cement,with the help of material dynamo experiment machine to do the axial compression tests,three point bending test,and torsion test in order to observe the biological dynamic changes.Optical microscope,fluorescence microscope and scanning electron microscope were used to observe the changes of micro bone cement and the changes of bone looseness.Nano-indentation testing was applied by the triboindenter to study the critical load.Results PMMA can rapidly establish the strong support with stable function in the near future.Biomechanical experiments showed that biomechanical properties of bone cement group was significantly higher than those in the other two groups.Biomechanical properties of bone cement group may decline with the time,but which were still better than those of OP in the control group.Histo-morphological observation result shows that under osteoporosis state the bone grows slower,bone's rebuilding time also extended.And in the later period,main bone's continuous osteoporosis had some impact on the interface.Nano-indentation testing showed that the young modulus and stiffness of the interface among bone,material and interface were significantly differences.Bone cement had showen the best nano indentation hardness,then was interface and bone tissue.Conclusion The polymethyl methacrylate bone cement llⅢ has a good effect in filling,on account of it has great plasticity and liquidity and can penetrate into the minuteness aperture between trabecula,then after solidifying,it will combine firmly with the host bone.PMMA can rapidly establish the strong support with stable function after operation.The performance is decreasing in the far future but still with satisfaction.

Objective To evaluate the endoscopic and pathologic characteristics and etiological ex-amination of viral esophagitis. Methods The data of 16 patients with viral esophagitis, including endoscop-ic, pathological and immunohistochemical findings were retrospectively studied. Results Endoscopic find-ings of viral esophagitis were characterized by single or multiple round and oval ulcers, located at the upper and middle esophagus. The surface of the ulcer was clean, and the boundary was distinct. Pathologic findings included degeneration and necrosis in squamons epithelium, accompanied by ulcer, infiltration of neutrophils and lymphocytes, hyperplasia of capillaries and basal cells and formation of granulation tissues, Immunocyto-chemical examination showed HSV-1 was positive in biopses, while CMV, EBV, HHV8 were negetive. Con-dusion Viral esophagtitis exhibited distinctive endosoopic and pathological features, and etiology can be confirmed by immunohistochemical examinations.

Objective To assess the clinical value of endoscopic uhrasonography(EUS)combined with the mini-probe endoscopic uhrasonography(MPUS)in determing tumor invasion depth and lymph node metastases of early superficial esophageal cancer.Methods One hundred and twenty-four superficial esophageal cancer lesions of 121 patients were staged by EUS combined with MPUS,and the results were finally compared with pathological findings of surgical specimens or samples obtained by mucosal resection.Results The diagnostic accuracy of EUS in T staging of superficial esophageal cancer was 82.3%(102/124).The total ratio of lymph node metastases was 5.0%(6/121),with no node metastases in carcinoma in situ,1.3%(1/28)in mucosal carcinoma,11.6%(5/43)in submucosal carcinoma.Conclusion EUS combined with MPUS is accurate in staging of the superficial carcinoma,which can help the choice of therapeutic strategies.

OBJECTIVE To investigate the characteristics of hypopharyngeal carcinoma detected by narrow band imaging(NBI)endoscopy and evaluate the value of NBI in the early diagnosis of hypopharyngeal carcinoma. METHODS Between December 2008 and July 2009,a total of 46 consecutive patients with hypopharyngeal squamous cell carcinoma were enrolled in this study. High performance endoscopic system equipped with the white light mode and NBI mode was introduced in the examination of pharynx and larynx. The quality of visualization of morphologies of epithelial capillary and demarcation line of each lesion under NBI view was evaluated in comparison with conventional white light endoscopy. RESULTS Among the 46 patients,a total of 86 lesions were detected. The notable characteristic of hypopharyngeal squamous cell carcinoma is the well demarcated brownish area and scattered brown dots. The NBI laryngoscope could provide better visualization of morphologies of epithelial capillary and demarcation line in superficial carcinoma of hypopharynx than the white light mode(P

Objective:To explore the accuracy of occlusal contacts on digital model made by intraoral scanner.Methods:Twenty healthy subjects [6 males, 14 females, (24.4±1.4) years old] with intact dentition were randomly recruited from postgraduate students in Capital Medical University School of Stomatology who volunteered to participate in this study. For each participant, the 2nd and 3rd quadrant of natural dentition was scanned. A diagnostic test design was performed. The occlusal contacts of the maximal intercuspal position (MIP) were extracted with the transillumination of silicone interocclusal records, and the extraction threshold was set as ≤50 μm. Intraoral scanning system was used to scan in MIP and generate occlusal contacts on digital model. Five groups were designed as test groups according to included tooth position: group 1 (buccal scanning ranged from tooth 21 to 23), group 2 (buccal scanning ranged from tooth 23 to 26), group 3 (buccal scanning ranged from tooth 24 to 26), group 4 (buccal scanning ranged from tooth 25 to 26), group 5 (buccal scanning ranged from tooth 21 to 26). Five groups occlusal contacts on digital model were generated respectively. According to the relevant literature, the upper occlusal surface was divided into 28 partitions, and the accuracy of occlusal contacts on digital model was calculated with the transillumination of silicone interocclusal records as the reference standard. Subgroup analysis was performed according to anterior teeth area, premolars area and molars area.Results:The accuracy of occlusal contacts on digital models of the half dentition in five buccal scanning positions were: group 1 (86.8%), group 2 (92.0%), group 3 (90.7%), group 4 (91.1%), group 5 (90.4%), and the accuracy of occlusal contacts in group 1 was significantly lower than those in the other four groups ( P<0.05). The accuracy of anterior teeth area were 85.6%-93.9%; the accuracy of premolar area were 92.5%-94.4%; the accuracy of molar area were 77.3%-93.6%, group 1 was significantly lower than those in the group 4 in molars area ( P<0.05), the accuracy of anterior area was statistically less than premolars area and molars area in group 1 ( P<0.05). There was no statistical difference in pairwise comparison between the three sections ( P>0.05). Conclusions:The digital models scanned intraoral methods provide accurate, quantitative measures of occlusal contacts when transillumination contacts are the reference standard.

Objective To evaluate the efficacy of endoscopic ultrasound guided fine-needle aspiration (EUS-FNA) in diagnosis of enlarged mediastinal lymph nodes (LNs), mediastinal occupying lesion of unknown origin, as well as in N-staging for lung cancer. Methods EUS-FNA was performed via esophagus with a 22-gange needle in 61 patients, followed by pathological and cytological examinations. Results The positive diagnosis rate of EUS-FNA was 93.4% (57/61), and the cytological and pathological diagnostic accuracy were 85.2% (52/61) and 83.6% (51/61), respectively. Of 61 patients, 26 were suspected as having lung cancer with mediastinal lymph nodes metastasis, but the bronchoscopy failed to confirm the diag-nosis. EUS-FNA diagnosed lung cancer in 21 and benign lesion in 5. Of 22 patients with mediastinal occupying lesions of unknown origin, 19 (86.4%) were diagnosed by EUS-FNA. Of 7 patients with malignant tumor history and enlarged mediastinal lymph nodes, EUS-FNA confirmed mediastinal metastasis in 6 (85.7%). Six cases of lung cancer with suspected mediastinal lymph nodes metastasis were confirmed by EUS-FNA and the corresponding therapy regimen was modified. No complications related to EUS-FNA procedure occurred. Conclusion EUS-FNA is a safe and effective method for diagnosis of enlarged medistinal LNs, mediastinal lesion of unkown origin and N-stage of lung cancer.

Objective: To evaluate the compliance rate of screening colonoscopy and associated factors in high-risk populations of colorectal cancer (CRC) in urban China. Methods: CRC screening data from the Program of Cancer Screening in Urban China conducted in 12 provinces in 2012-2014 was used in the present study. All 97 445 participants were asked to take epidemiological questionnaire survey to evaluate their cancer risk. Participants who were evaluated as "high risk for CRC" were recommended to receive colonoscopy at designated hospitals. Chi-square tests were used to compare the differences of participation rates between groups. Multivariate logistic regression models were applied to explore the potential factors associated withthe compliance rate of screening colonoscopy. Results: Overall, 97 445 participants of CRC high-risk were included in this analysis, and 14 949 of them took screening colonoscopy, yielding a participation rate of 15.3%. The participation rate varied greatly across provinces, ranging from 25.2% (2 785/11 071) in Heilongjiang to 9.7% (1 698/17 515) in Liaoning. Moreover, the participation rate in 2013-2014 was significantly higher than that in 2012-2013 (17.1%(9 766/57 280) vs 12.9% (5 183/40 165), χ²=57.67, P<0.001) . The multivariate logistic regression analyses showed that: compared with individuals of 40-49 years old, individuals of 50-59 or 60-69 years old were more willing to accept screening colonoscopy, with OR of 1.17 (95% CI: 1.12-1.22) and 1.13 (95% CI: 1.08-1.19), respectively; compared with uneducated individuals, individuals with good educational background of equivalent to high school or higher (OR=1.29, 95% CI:1.10-1.50) were more willing to accept screening colonoscopy; compared with individuals who never took fecal occult blood tests (FOBT) before, individuals with previous positive FOBT results (OR=1.40, 95% CI:1.31-1.50) were more willing to accept screening colonoscopy; compared with individuals with no inflammatory bowel diseases (IBD), individuals with IBD (OR=1.63, 95%CI:1.56-1.69) were more willing to accept screening colonoscopy; Compared with individuals without polyp history, individuals having history of previous polyp detection (OR=1.43, 95% CI:1.37-1.50) were more willing to accept screening colonoscopy; compared to individuals with no family history of CRC, individuals with history of CRC (OR=1.60, 95% CI:1.53-1.66) were more willing to accept screening colonoscopy. Conclusion The overall participation rate of screening colonoscopy among high-risk population of CRC in the 12 participating sites was 15.3%. The study findings indicated that age, education level, history of past fecal occult blood test, IBD, history of polyp, family history of CRC were associated with the compliance rate of colonoscopy in this population-based CRC screening program.

Objective:This study was to systematically update the economic evaluation evidence of colorectal cancer screening in mainland China.Methods:Based on a systematic review published in 2015, we expanded the scope of retrieval database (PubMed, EMbase, The Cochrane Library, Web of Science, CNKI, Wanfang Data, VIP, CBM) and extended it to December 2018. Focusing on the evidence for nearly 10 years (2009-2018), basic characteristics and main results were extracted. Costs were discounted to 2017 using the consumer price index of medical and health care being provided to the residents, and the ratio of incremental cost-effectiveness ratio (ICER) to per capita GDP in corresponding years were calculated.Results:A total of 12 articles (8 new ones) were included, of which 9 were population-based (all cross-sectional studies) and 3 were model-based. Most of the initial screening age was 40 years (7 articles), and most of the frequency was once in a lifetime (11 articles). Technologies used for primary screening included: questionnaire assessment, immunological fecal occult blood test (iFOBT) and endoscopy. The most commonly used indicator was the cost per colorectal cancer detected, and the median (range) of the 20 screening schemes was 52 307 Chinese Yuan (12 967-3 769 801, n=20). The cost per adenoma detected was 9 220 Yuan (1 859-40 535, n=10). In 3 articles, the cost per life year saved (compared with noscreening) was mentioned and the ratio of ICER to GDP was 0.673 (-0.013-2.459, n=11), which was considered by WHO as "very cost-effective" ; The range of ratios overlapped greatly among different technologies and screening frequencies, but the initial age for screening seemed more cost-effective at the age of 50 years (0.002, -0.013-0.015, n=3), than at the 40 year-olds (0.781, 0.321-2.459, n=8). Conclusions:Results from the population-based studies showed that the cost per adenoma detected was only 1/6 of the cost per colorectal cancer detected, and limited ICER evidence suggested that screening for colorectal cancer was generally cost-effective in Chinese population. Despite the inconclusiveness of the optimal screening technology, the findings suggested that the initial screening might be more cost-effective at older age. No high-level evidence such as randomized controlled trial evaluation was found.

Objective: To investigate the risk factors and survival status of hypopharyngeal carcinoma with synchronous second primary carcinoma of the esophagus. Methods: One hundred and sixty patients with newly diagnosed hypopharyngeal carcinoma from January 2009 to December 2012 were retrospectively reviewed. The clinical data, tumor-related information and follow-up results were collected and analyzed. Results: Forty-three synchronous esophageal carcinomas (27%) were detected in 160 patients with hypopharyngeal carcinoma, and most patients (72%) were at an early stage. On univariate analysis, the median age of less than 55 years old (χ²=4.525, P=0.033), excessive alcohol consumption (χ²=6.942, P=0.008) and invasion site more than 3 anatomical regions (χ²=21.503, P=0.000) had a significant correlation with the occurrence of synchronous esophageal carcinomas. Multivariate analysis showed that excessive alcohol consumption (OR=4.787, P=0.029) and invasion site more than 3 anatomical regions (OR=14.391, P=0.000) were independent risk factors. The median survival time was 26 months in 43 patients with synchronous esophageal carcinomas, which was significantly lower than that (58 months) in patients without secondary primary esophageal carcinomas (χ²=11.981, P=0.001). Conclusions There is a high incidence of synchronous esophageal carcinoma in hypopharyngeal carcinoma patients, affecting the prognosis of hypopharyngeal carcinoma. Surveillance for esophageal carcinomas in patients with hypopharyngeal carcinoma, especially in excessive alcohol drinkers, is warranted.