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The acetylation of 3,4-diaminofurazan, the nitration of its acetylated products and the rearrangement-decomposition of nitrated products were studied in this work. Under the catalysts of p-Toluenesulfonic acid, the products of 3-amino-4-acetylaminofurazan and 3, 4-diacetyl-aminofurazan were got respectively by using acetic acid and acetic anhydride to acetylate 3,4-diaminofurazan. It is found that, when the reaction time is 3 hours for 3-amino-4-acetylamino-4-diaminofurazan and 10 minutes for 3,4-diacetyl-aminofurazan, the yields of products reach the maximum of 78% and 89%, respectively. The 3-acetylamino-4-nitrylaminofurazan was also prepared when 3,4-diacetylaminofurazan was nitrified in the mixture of nitric acid and acetic anhydride and the maximum yield is 54% when the reaction temperature between 0 °C and -- 5 °C. Under the catalysts of dram acid, the rearrangement and following with decomposition reaction of 3-acetylamino-4-nitryl-aminofurazan surrounded in THF would occur to yield 3-acetylaminofurazan. [ABSTRACT FROM AUTHOR]

Objective: Genome-wide association studies (GWAS) of gastric cancer have reported differences in single-nucleotide polymorphism (SNP) associations for tumour subtypes, particularly when divided by location into the gastric cardia versus the non-cardia., Design: Here we present results for a GWAS using 2350 East Asian gastric cancer cases divided as 1189 gastric cardia and 1027 gastric non-cardia cases and 2708 controls. We also included up to 3042 cardia cases, 4359 non-cardia cases and 7548 controls for replication from two Chinese studies and one Korean study. From the GWAS, we selected 12 top SNPs for each gastric cancer subtype, 4 top SNPs for total gastric cancer and 1 SNP in MUC1 for replication testing., Results: We observed genome-wide significant associations for rs10074991 in PRKAA1 at 5p13.1 for cardia (p=7.36×10(-12)) and non-cardia cancers (p=2.42×10(-23)) with per allele OR (95% CI) for the combined endpoint of 0.80 (0.77 to 0.83). At 6p21.1, rs2294693 near UNC5CL was significantly associated with gastric non-cardia cancer risk (p=2.50×10(-8)), with OR (95% CI) of 1.18 (1.12 to 1.26), but there was only a nominal association for cardia cancer (p=1.47×10(-2)). We also confirmed a previously reported association for rs4072037 in MUC1 with p=6.59×10(-8) for total gastric cancer and similar estimates for cardia and non-cardia cancers. Three SNPs in PSCA previously reported to be associated with gastric non-cardia cancer showed no apparent association for cardia cancer., Conclusions: Our results suggest that associations for SNPs with gastric cancer show some different results by tumour location in the stomach., (Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/)

Objective: To compare the peri-implant tissue stability between immediate implant and delayed implant in maxillary anterior region after loading 2 years., Methods: In the study, 38 patients with single anterior tooth loss in the Second Clinical Division of Peking University School and Hospital of Stomatology from October 2010 to December 2011 were enrolled, and 43 implants were inserted. The gingival contour was induced using implant-supported temporary crowns prior to restoration till permanent prostheses delivered. The gingival papilla height, labial gingival margin level and peri-implant bone level were measured immediately after the permanent restoration and 2 years later., Results: In the study, 16 patients were treated by immediate implant for 17 implants; 22 patients were treated by delayed implant for 26 implants. The implant stability quotient (ISQ) value of the 2 groups showed no significant difference before permanent restoration (P>0.05). In all the cases after loading 2 years, the average mesial gingival papilla height in the implant area of the immediate group and delayed group increased by (0.15 ± 0.42) mm and (0.06 ± 0.65) mm, respectively; the distal gingival papilla height increased by (0.06 ± 0.50) mm and (0.02 ± 0.57) mm respectively; while the labial gingival margin level shrinkages were (0.15 ± 0.23) mm and (0.15 ± 0.46) mm, respectively. The peri-implant bone losses in the mesial side were (0.67 ± 0.35) mm and (0.6 9 ± 0.49) mm, respectively, while in the distal side were (0.73 ± 0.31) mm and (0.75 ± 0.48) mm, respectively. All these indicators showed no significant difference between the 2 groups (P>0.05)., Conclusion: Both the cases obtained optimizer results after loading 2 years, and the soft and hard tissues around the implant were very stable, which means that both the protocols can achieve reliable therapeutic effects. If we can handle the indications, immediate implant for anterior teeth shows similar efficacy with delayed implant in the short term. But immediate implant in terms of shortening the course of treatment is clearly superior to delayed implant.

Objectives: To explore the method of manufacturing an implant surgery template with a computer-aided design/computer-aided manufacturing (CAD/CAM) technique and evaluate its precision in clinical cases., Methods: Patients referred to the 2nd Dental Center of Peking University who were partially edentulous, were enrolled and scanned with cone beam computed tomography (CBCT). Diagnostic casts were laser scanned to record the configuration of the patients' dentition and mucosae. CBCT and laser scanning data were subsequently loaded into Simplant software. Implant positions were planned in the software with a computer-aided design technique, and surgical templates were fabricated with a rapid prototyping technique. These templates were used to guide implant placement surgery., Results: The mean value of linear deviation was 1.00 mm (range 0 to 2.16 mm) for implant shoulder and 1.26 mm (range 0.51 to 2.86 mm) for the implant apex. The mean angular deviation was 4.74 degress (0.37 to 10.28 degrees). Deviations were higher in the posterior region than anterior. The tooth-supported template provided higher precision than did the tooth/ mucosa-supported template, but no statistically significant difference was found., Conclusion: Computer-guided implant surgery with the CAD/CAM technique provides dentists with a good platform for preoperative planning, precise implant insertion, and ideal rehabilitation. The protocol of this three-dimensional laser scanning technique can provide precision comparable to that of double-scanning.

Objective: To evaluate the clinical results of computer aided design and computer aided manufacturing (CAD/CAM) titanium-ceramic-fixed partial dentures for implant-supported restoration in posterior region., Methods: In the study, 90 patients (47 males, 43 females, and the mean age of 48.7 years ranging from 30-62 years) with posterior tooth missing underwent implant-supported porcelain fuse mental prostheses with CAD/CAM titanium-base. A total of 135 prostheses (159 prosthetic units) were fabricated, and 152 implants were placed. The evaluators examined the integrity of restoration, gingival health, color match and marginal adaptation. The mean follow-up time was 51.9 months (24-80 months)., Results: No implant was lost during the loading time. All the patients were satisfied at the end of their treatment. The chipping rate of porcelain fuse mental prostheses with CAD/CAM titanium-base was 13.2%(21/159 prosthetic units), No fracture of titanium-base was observed, and 7.4% (10/135) prostheses were found loosening. The authors rated 97.8% (132/135) prosthesis as good or better in regard to color match, 100% (152/152) implants had excellent marginal adaptation., Conclusion: The implant-supported titanium-based porcelain fuse mental prostheses with CAD/CAM show good marginal integrity and shade stability, with a clinically acceptable chipping rate, and these restorations can achieve success in the case of posterior tooth missing. Further study is needed to determine the long-term results.

Objective: To form a wound information management scheme with objectivity, standardization, and convenience by means of wound information management system., Methods: A wound information management system was set up with the acquisition terminal, the defined wound description, the data bank, and related softwares. The efficacy of this system was evaluated in clinical practice., Results: The acquisition terminal was composed of the third generation mobile phone and the software. It was feasible to get access to the wound information, including description, image, and therapeutic plan from the data bank by mobile phone. During 4 months, a collection of a total of 232 wound treatment information was entered, and accordingly standardized data of 38 patients were formed automatically., Conclusions: This system can provide standardized wound information management by standardized techniques of acquisition, transmission, and storage of wound information. It can be used widely in hospitals, especially primary medical institutions. Data resource of the system makes it possible for epidemiological study with large sample size in future.

Assessment of compost maturity is crucial for achieving high quality compost in order to guarantee its marketability. In this context, a novel technique that combines fluorescence excitation-emission matrices (EEMs) with parallel factor (PARAFAC) analysis to assess compost maturity is presented. A total of 60 fluorescence EEMs of composts were successfully decomposed into a three-factor model using PARAFAC analysis. Components 1 [excitation/emission (Ex/Em) wavelengths=(230, 330)/410] and 2 [Ex/Em wavelengths=(250, 350)/450] were attributable to humic-like and fulvic-like substances, whereas component 3 [Ex/Em wavelengths=(220, 280)/340] belonged to protein-like substances. Pearson correlation analysis between the common maturity indices and log scores of three components demonstrated that components 1 and 3 are more suitable to assess compost maturity than component 2. These results reveal that EEM-PARAFAC could be applied as a valuable tool for assessing compost maturity, given its high sensitivity and selectivity., (Copyright 2010 Elsevier Ltd. All rights reserved.)

Objective: To evaluate the treatment effects of the half-columnar shaped mandibular block bone onlay grafting technique for augmentation of the resorbed maxillary anterior alveolar ridge after single tooth missing., Methods: A total of 15 sites of 14 patients received ridge augmentation surgeries. The recipient sites were prepared with trephines, the half-columnar shaped bone blocks were harvested from the ramus and external oblique ridges with trephines according to diameters of the recipient sites. The bone blocks were placed as lateral onlay grafts on recipient beds and secured by means of titanium screws. Particulate bone was added and absorbable membranes were used to stabilize and protect the grafts. After a mean interval of 4.5 months of healing the flaps were re-opened, the screws were removed and non-submerged implants were placed. The width and height of the alveolar ridges were recorded. After 3 months, implant-supported crowns were provided to the patients. One year later, the peri-impant condition and the marginal bone resorption on the proximal sites were observed., Results: Mean lateral augmentation obtained at the time of bone grafting was (3.8 + or - 0.8) mm, 5 out of 15 sites exhibited a mean of 3 mm of vertical augmentation. The mean healing time was 4.5 months, the mean percentage of horizontal and vertical bone resorption in the mean time were 8% and 7% respectively. No major complications were recorded at donor sites. No implant was lost during the study period. Clinical parameters and probing depth (< or = 4 mm) demonstrated the presence of a healthy peri-implant mucosa after 1 year of prosthetic reconstruction. The clinical and radiographic bone observations showed no more than 1.2 mm of resorption after bone graft and implant placement., Conclusion: The half-columnar shaped mandibular bone graft (from the ramus and external oblique ridge) is a promising technique for bone augmentation in localized alveolar ridge defects after single tooth missing. This procedure offers easy access, good bone quantity for localized repair, low morbidity, decreased complaints of postoperative sensory disturbances or discomfort, minimal graft resorption, and a shorter healing time as compared with other methods for bone repair.