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121.
Cheol Woong Choi Gwang Ha Kim Dae Hwan Kang Hyung Wook Kim Dong Uk Kim Jeong Heo Geun Am Song Do Youn Park Suk Kim 《World journal of gastroenterology : WJG》2010,16(34):4329-4334
AIM: To identify the associated risk factors for hyperechogenic pancreas (HP) which may be observed on endoscopic ultrasound (EUS) and to assess the relationship between HP and obesity. METHODS: From January 2007 to December 2007, we prospectively enrolled 524 consecutive adults who were scheduled to undergo EUS. Patients with a history of pancreatic disease or with hepatobiliary or advanced gastrointestinal cancer were excluded. Finally,284 patients were included in the analyses. We further analyzed the ri... 相似文献
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A new human leukocyte antigen-Cw*0401 allele showed one nucleotide difference from Cw*04010101 in exon 3 at nucleotide position 561 (codon 163 ACG→ACT) without a coding change. 相似文献
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A histomorphometric analysis of the effects of various surface treatment methods on osseointegration 总被引:4,自引:0,他引:4
Kim YH Koak JY Chang IT Wennerberg A Heo SJ 《The International journal of oral & maxillofacial implants》2003,18(3):349-356
PURPOSE: One major factor in the success and biocompatibility of an implant is its surface properties. The purposes of this study were to analyze the surface characteristics of implants after blasting and thermal oxidation and to evaluate the bone response around these implants with histomorphometric analysis. MATERIALS AND METHODS: Threaded implants (3.75 mm in diameter, 8.0 mm in length) were manufactured by machining a commercially pure titanium (grade 2). A total of 48 implants were evaluated with histomorphometric methods and included in the statistical analyses. Two different groups of samples were prepared according to the following procedures: Group 1 samples were blasted with 50-microm aluminum oxide (Al2O3) particles, and group 2 samples were blasted with 50-microm Al2O3, then thermally oxidized at 800 degrees C for 2 hours in a pure oxygen atmosphere. A noncontacting optical profilometer was used to measure the surface topography. The surface composition of the implants used and the oxide thickness were investigated with Rutherford backscattering spectrometry. RESULTS: The different preparations produced implant surfaces with essentially similar chemical composition, but with different oxide thickness and roughness. The morphologic evaluation of the bone formation revealed that: (1) the percentage of bone-to-implant contact of the oxidized implants (33.3%) after 4 weeks was greater than that of the blasted group (23.1%); (2) the percentages of bone-to-implant contact after 12 weeks were not statistically significantly different between the groups; (3) the percentages of bone area inside the thread after 4 weeks and 12 weeks were not statistically significantly different between groups. DISCUSSION AND CONCLUSION: This investigation demonstrated the possibility that different surface treatments, such as blasting and oxidation, have an effect on the ingrowth of bone into the thread. However, the clinical implications of surface treatments on implants, and the exact mechanisms by which the surface properties of the implant affect the process of osseointegration, remain subjects for further study. 相似文献
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Dental technicians are exposed to various dusts in working laboratories. This study was conducted to measure level of silica in the respirable dust generated from dental fixed prosthodontics manufacturing processes using Fourier Transform Infrared Spectroscopy (FTIR), and to compare their occurrence of respiratory symptoms with that of non-dental hospital workers (control group). Respirable dusts were personally sampled from dental technicians working at dental laboratories in Seoul Korea according to NIOSH Method 0600. Fifty personal samples were obtained during porcelain or polishing process and weighed by a gravimetric method. Concentration of respirable dust was 651 +/- 548 microg/m3 (Mean +/- SD) with highest concentration of 2,874 microg/m3 during the porcelain process and 725 +/- 414 microg/m3 with highest concentration of 1,764 microg/m3 during the polishing process. Concentration of silica was 6.51 +/- 6.07 microg/m3 with 18.85 microg/m3 highest and 14.88 +/- 11.21 microg/m3 with 50.98 microg/m3 highest for the porcelain and polishing process, respectively. Level of silica contents in the dust was 0.81% and 1.66% for the porcelain and polishing process, respectively. The level of silica contents and silica concentration were significantly different between the two processes. Comparing prevalence of respiratory symptoms between non-smoking seventeen dental technicians and thirty-five control workers, wheezing and rhinorrhea were significantly more manifested in the dental technicians than the controls. Total frequency of respiratory symptoms was also significantly higher in the dental technicians than the controls. 相似文献
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Kim KM Shin EY Moon JH Heo TH Lee JY Chung Y Lee YJ Cho HM Shin SU Kang CY 《International journal of cancer. Journal international du cancer》2002,102(4):428-434
The Her-2/neu oncogene, which encodes a growth factor receptor, was implicated in the malignancy of human adenocarcinomas. Antibodies directed to this molecule have been previously shown to have an antitumor effect in vivo. In an attempt to understand the mechanisms of the antitumor activity, we generated 2 monoclonal antibodies (mAbs), HRO G1 and HRT G1, that recognize different epitopes on Her-2/neu. Both of the mAbs bound HER2/neu on the tumor surface, resulting in phosphorylation of HER2/neu. We also generated IgG2a and IgG2b mAbs from these 2 mAbs, respectively. The results of in vitro studies showed that these anti-Her-2/neu mAbs could not inhibit the growth of the tumor cells that express Her-2/neu molecules by themselves. However, in an antibody-dependent cellular cytotoxicity study using mouse splenocytes as effector cells, HRT mAbs had antitumor activities superior to those of HRO mAbs, indicating that the epitope specificity may also partake in antibody-dependent cellular cytotoxicity with antibody isotype. In a complement-dependent cytotoxicity study, the IgG2a and IgG2b mAbs showed stronger effects than IgG1 isotype mAbs irrespective of the epitope specificities. The results of in vivo studies also showed that HRT mAbs had superior antitumor activity to those of HRO mAbs. The antitumor activity was most prominent in the HRT G2b isotype among HRT mAbs. HRT G1 also showed a moderate antitumor effect, while HRT G2a showed only slight inhibition effect. These data indicate that both the epitope specificity and the differences in Fc region of mAbs could play important roles in the antitumor activities. 相似文献