• The Journal of Korean Academy of Prosthodontics
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• v.37 no.2
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• pp.143-166
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• 1999

The success of porcelain laminate veneer depends on the bond strength between tooth structure and ceramic restoration and the design of tooth preparation. In particular, incisal coverage and incisal finish line are the two most important factors in long-term fracture resistance. Although the majority of clinicians are practicing incisal coverage and there are various opinions on the geo-metrical ratio between the clinical crown length of the remaining tooth structure and the length of incisal extension in porcelain laminate veneer and the optimal incisal finish lines. scientific evidence still loaves much to be desired. The purpose of this study was to determine the effects of the amounts of incisal coverage and the types of incisal finish line on the stress distribution in maxillary anterior porcelain laminate veneers under two different loading conditions. Three-dimensional finite element models of a maxillary anterior porcelain veneer with differ-ent amounts of incisal coverage ; 0, 1, 2, and 3mm and different incisal finish lines feathered edge, incisal bevel, reverse bevel and lingual chamfer with various amounts of lingual extension were developed. 300N force was applied at the point 0.5mm cervical of the linguoincisal edge in two loading conditions ; A) 125 degrees, B) 132 degrees. Tensile and compressive stress in ceramic and shear stress in the resin cement layer were analyzed using three-dimensional finite element method. The results were as follows : 1. The types of incisal finish line had more influence on the stress distribution in porcelain laminate veneer than the amounts of incisal coverage. 2. In case of no incisal coverage, incisal beveled laminate exhibited more evenly distributed tensile stress than feathered edged laminate. And in case of incisal coverage, reverse beveled laminate and lingual chamfered laminate with 1mm lingual extension exhibited more evenly distributed tensile stress than lingual chamfered laminates with 2mm and 3mm lingual extension. 3. As long as the lingual chamfer goes, less tensile stress was found at the incisal edge, while much more tensile stress was found at the lingual margin area in proportion to the length of lingual extension. 4. Under 125 degree load, tensile stress in porcelain laminate veneer had increased compared with that under 132 degree load and the difference exhibited by the change of the amount of tooth support was larger. 5. The types of incisal finish line and the distance from the incisal finish line to the loading point had more influence on the shear stress distribution in the resin cement layer than the amounts of incisal coverage. In contrast loading condition had little influence.

• Journal of Acupuncture Research
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• v.25 no.2
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• pp.199-210
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• 2008

Backgrounds : Electroacupuncture(EA) is commonly used in treatment of various disease. Despite an extensive evidence-base guiding the selection of stimulation parameters, little methodologically robust research regarding the level of intensity and frequency in need to provide effective doses. Objectives : This study is evaluated effects of various intensities and frequencies of EA's stimulation at $ST_{36}$, Zusanli, with sex and age in rats. Methods : In this study, we measured the effects of EA treatment on transfer capability of small intestine in rats. Under anesthesia, two intensities, 1, 5mA with three different frequencies, 2, 50, 100Hz were applied to the groups divided with sex and age for 30minutes. Results : 1mA-2Hz, 5mA-2, 100Hz in male and 1mA-2, 50, 100Hz in female without distinction of age elicited an increasing trend in transfer capability of small intestine. In case of 2Hz in male, it showed the effects of EA without strength or weakness of stimulation and it need 100Hz stimulation additionally with age. In the groups of 1mA-2Hz, 5mA-2Hz in male and 1mA-2Hz, 1mA-100Hz, we elicited the decreasing trend with growing of weeks-old in male. Conclusions : With this result, it was suggested that we should consider a correlation of sex, age and EA's intensities, frequencies for the efficient EA.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.10
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• pp.5263-5272
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• 2012

Background: Gastric cancer (GC) is one of the most common cancers in China. Adjuvant chemotherapy (AC) is a routine auxiliary treatment for GC recommended by the guidelines issued in 2011 by the Ministry of Health of the People's Republic of China, but the relevant credible consequences in China have been insufficient because of China's late start and ethical concerns. Methods: A series of databases, including Cochrane Library, MEDLINE, EMBASE, the Chinese database of the National Knowledge Infrastructure and the VIP database, were searched by 2 reviewers independently for studies investigating AC for GC through March 2012. The retrieved literature was screened according to the eligibility criteria. Results: A total of 35 randomized control trials (RCTs) were subjected to the final analysis, including 4,043 patients in treatment group and 3,884 in the control group, as well as 4 clinical-control trials (CCTs), which accessed the final analysis with 238 and 252 patients, respectively. AC reduced the risk of death as a protective treatment with statistical significance (HR=0.91, 95%CI: [0.85, 0.97], P=0.002), and it seemed more effective for Asian than non-Asian patients. The effects of AC were not influenced by the starting time (P>0.05). D2 lymphadenectomy-based chemotherapy was effective (HR=0.89, 95%CI: [0.80, 0.99], P=0.04). Oral S-1 40 mg/m2 after D2 lymphadenectomy might be a better choice for Asians with advanced GC and might result in a greater reduction of adverse events than in non-Asian patients. GRADE quality assessment determined that the strength of the evidence from foreign studies from Europe, the United States and Asian countries other than China was high, while it was moderate for Chinese studies. Conclusion: AC was effective or even curative in Chinese patients in general, although it is still necessary to optimize a targeted AC scheme for Chinese patients with GC.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.19
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• pp.8279-8285
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• 2014

A meta-analysis incorporating 34 case-control studies from 19 articles involving 12,197 cases and 13,488 controls was conducted to assess the effects of three genetic variants of Toll-like receptor 9 (TLR9): rs187084, rs352140, and rs5743836. Studies on associations between TLR9 polymorphisms and cancer risk were systematically searched in electronic databases. The reported odds ratios (OR) and 95% confidence intervals (CI) were pooled to assess the strength of any associations. The results showed that the rs187084 polymorphism was significantly associated with an increased risk of cancer (CC vs TC+TT: OR=1.14, 95% CI=1.02-1.28), specifically cervical cancer (C vs T: OR=1.19, 95% CI=1.05-1.34; TC vs TT: OR=1.32, 95% CI=1.10-1.58; CC vs TT: OR=1.31, 95% CI=1.03-1.68; CC+TC vs TT: OR=1.32, 95% CI=1.11-1.56), and that this association was significantly positive in Caucasians (CC vs. TC+TT: OR=1.18, 95% CI=1.01-1.38). The rs352140 polymorphism had a protective effect on breast cancer (GA vs GG: OR=0.77, 95% CI=0.66-0.89), whereas the rs5743836 polymorphism was likely protective for digestive system cancers (CC+TC vs TT: OR=0.81, 95% CI=0.66-0.98). In conclusion, our results suggest that the rs187084 polymorphism may be associated with an elevated cancer risk, whereas polymorphisms of rs352140 and rs5743836 may play protective roles in the development of breast and digestive system cancers, respectively. From the results of this meta-analysis further large-scale case-control studies are warranted to verify associations between TLR9 polymorphisms and cancer.

• Information Systems Review
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• v.11 no.1
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• pp.19-47
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• 2009

Many products today tend to adopt a convergence approach by adding new features or functionalities to the existing products. The convergence, however, results in both positive and negative effects on usage of products, and thus demonstrates the characteristics called "paradox of technology." On the one hand, the added functionalities or features will increase the usefulness of the products. On the other hand, the convergence increases complexity of learning and usage of products and may decrease satisfaction or user evaluations. This study provides an empirical evidence of this paradox through investigation of telematics, one of the exemplary products of convergence services. Our research model is designed to test the existence of the "paradox of technology" and includes variables such as variety of functions, complexity of usage, perceived usefulness, service evaluation, and service fit. The proposed research model and subsequent hypotheses are empirically tested using 149 survey responses from telematics users. We have found that the variety of functions is positively associated with perceived usefulness, but is negatively associated with the complexity of usage. The data analysis reveals that the perceived usefulness has more significant impacts on service evaluation than the complexity of usage does. Furthermore, the strength of causal relationships among these variables is partially moderated by the degree of service fit. This study thus highlights the paradox of technology in explaining user attitudes and beliefs associated with convergence services.

• Journal of Korean Society for Atmospheric Environment
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• v.25 no.6
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• pp.523-538
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• 2009

Recently, there has been a keen demand for real-time automatic monitoring of VOCs not only in Korea but other developed countries. We carried out this study to evaluate and to optimize the performance of a continuous automatic monitoring system for hazardous VOCs (HVOCs) in the ambient atmosphere, using an on-line GC system. The online system normally consisted of a Nafion dryer prior to a cold trap of an automatic thermal desorption apparatus and a GC system equipped with two detectors, i.e. PID and ECD. Preliminary tests conducted to check out any contamination of the system revealed an evidence of significant artifact formation of benzene, and it was found that the Nafion dryer (even brand new one) is the source of the benzene artifact. Thus, all the subsequent experiments in this study was carried out inevitably by removing the Nafion dryer. The on-line GC method was investigated with a variety of QC/QA performance criteria such as repeatability, linearity, lower detection limits, and accuracy. In order to find out the best operating condition for the on-line GC system, three different types (in terms of adsorption strength) of cold trap combinations were tested, i.e. (i) Tenax-TA and Carbopack-B combination (weak and hydrophobic); (ii) Tenax-TA, Carbopack-X and Carboxen-1000 combination (strong and hydrophilic); and (iii) Tenax-TA and Carbopack-X combination (medium and hydrophobic/hydrophilic). The USEPA TO-17 manual method was selected as a reference method to evaluate the performance of the on-line method. A series of experiments revealed that the system performance was superior to others when a cold trap packed with hydrophilic adsorbents (Tenax-TA/Carbopack-X/Carboxen-1000 combination) was used and operated at $25^{\circ}C$. However, the system with a cold trap packed with a combination of Tenax-TA and Carbopack-X is more recommended for field applications since the carboxen-1000 adsorbent is too sensitive to water vapor, and hence the performance of the system might be very unstable to humid samples or during rainy days. Furthermore, the precision and accuracy criteria of the Tenax-TA/ Carbopack-X combination were generally compatible with the triple adsorbents cold trap. The continuous automatic monitoring method is, thus, considered very useful to real-time monitoring to understand the variations of VOCs concentrations in ambient air, as it adopts much simpler procedures in sampling, analysis, and data integration steps than manual monitoring methods. However, it should be noted that there is a high possibility of benzene artifacts formation through the Nafion dryer, which is often installed to remove water vapor in air samples before being adsorbed onto the cold trap. Therefore, if a Nafion dryer is used in any studies of monitoring VOCs, the benzene contamination should be carefully examined before carrying out obtaining the data.

• Korean Journal of Radiology
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• v.21 no.4
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• pp.422-430
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• 2020

The Korean Society of Urogenital Radiology (KSUR) aimed to present a consensus statement for patient preparation, standard technique, and pain management in relation to transrectal ultrasound-guided prostate biopsy (TRUS-Bx) to reduce the variability in TRUS-Bx methodologies and suggest a nationwide guideline. The KSUR guideline development subcommittee constructed questionnaires assessing prebiopsy anticoagulation, the cleansing enema, antimicrobial prophylaxis, local anesthesia methods such as periprostatic neurovascular bundle block (PNB) or intrarectal lidocaine gel application (IRLA), opioid usage, and the number of biopsy cores and length and diameter of the biopsy needle. The survey was conducted using an Internet-based platform, and responses were solicited from the 90 members registered on the KSUR mailing list as of 2018. A comprehensive search of relevant literature from Medline database was conducted. The strength of each recommendation was graded on the basis of the level of evidence. Among the 90 registered members, 29 doctors (32.2%) responded to this online survey. Most KSUR members stopped anticoagulants (100%) and antiplatelets (76%) one week before the procedure. All respondents performed a cleansing enema before TRUS-Bx. Approximately 86% of respondents administered prophylactic antibiotics before TRUS-Bx. The most frequently used antibiotics were third-generation cephalosporins. PNB was the most widely used pain control method, followed by a combination of PNB plus IRLA. Opioids were rarely used (6.8%), and they were used only as an adjunctive pain management approach during TRUS-Bx. The KSUR members mainly chose the 12-core biopsy method (89.7%) and 18G 16-mm or 22-mm (96.5%) needles. The KSUR recommends the 12-core biopsy scheme with PNB with or without IRLA as the standard protocol for TRUS-Bx. Anticoagulants and antiplatelet agents should be discontinued at least 5 days prior to the procedure, and antibiotic prophylaxis is highly recommended to prevent infectious complications. Glycerin cleansing enemas and administration of opioid analogues before the procedure could be helpful in some situations. The choice of biopsy needle is dependent on the practitioners' situation and preferences.

• Physical Therapy Korea
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• v.28 no.1
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• pp.18-26
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• 2021

Previous studies have reported that deep neck flexor (DNF) exercise can improve neck problems, including neck pain, forward head posture, and headache, by targeting the deep and superficial muscles of the neck. Despite the prevailing opinion across studies, the benefits of DNF can vary according to the type of neck problems and the outcome measures adopted, ranging from positive outcomes to non-significant benefits. A meta-analysis was conducted in this study to assess conclusive evidence of the impact of DNF exercise on individuals with neck problems. We used PUBMED, MEDLINE, NDSL, EMBASE, and Web of Science to search for primary studies and the key terms used in these searches were "forward head posture (FHP)," "biofeedback," "pressure biofeedback unit," "stabilizer," "headache," and "neck pain." Twenty-four eligible studies were included in this meta-analysis and were coded according to the type of neck problems and outcome measures described, such as pain, endurance, involvement of neck muscle, craniovertebral angle (CVA), neck disability index (NDI), cervical range of motion (CROM), radiographs of the neck, posture, strength, endurance, and headache disability index. The overall effect size of the DNF exercise was 0.489. The effect sizes of the neck problems were 0.556 (neck pain), -1.278 (FHP), 0.176 (headache), and 1.850 (mix). The effect sizes of outcome measures were 1.045 (pain), 0.966 (endurance), 0.894 (deep neck flexor), 0.608 (superficial neck flexor), 0.487 (CVA), 0.409 (NDI), and 0.252 (CROM). According to the results of this study, DNF exercise can effectively reduce neck pain. Thus, DNF exercise is highly recommend as an effective exercise method for individuals suffering from neck pain.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.21
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• pp.9295-9300
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• 2014

Interleukin-17A (IL-17A) is a multifunctional cytokine which plays a crucial role in the initiation and progression of cancer. To date, several studies have investigated associations between IL-17A -197G>A (rs2275913) polymorphism and digestive cancer risk, but the results remain conflicting. We here aimed to confirm the role of this single nucleotide polymorphism (SNP) in susceptibility to digestive cancer through a systemic review and meta-analysis. Ten eligible case-control studies were identified by searching electronic databases, involving 3,087 cases and 3,815 controls. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to estimate the strength of the association. The results of overall analyses indicated that the variant A allele was associated with an increased risk of digestive cancer (AA vs GG: OR=1.51, 95%CI=1.18-1.93; AA vs GG+GA: OR=1.45, 95%CI=1.12-1.87; A vs G: OR=1.21, 95%CI=1.05-1.39). In subgroup analysis stratified by specific cancer type, elevated risk among studies of gastric cancer was found (AA vs GG: OR=1.68, 95%CI=1.24-2.28; AA vs GG+GA: OR=1.62, 95%CI=1.16-2.26; A vs G: OR=1.23, 95%CI=1.04-1.46). According to ethnicity, there was evidence in the Asian populations for an association between this polymorphism and cancer risk (GA vs GG: OR=1.19, 95%CI=1.05-1.36; AA vs GG: OR=1.56, 95%CI=1.15-2.12; AA+GA vs GG: OR=1.28, 95%CI=1.13-1.44; AA vs GG+GA: OR=1.42, 95%CI=1.01-2.00; A vs G: OR=1.24, 95%CI=1.08-1.44), while in the Caucasian populations an association was found in the recessive model (AA vs GG+GA: OR=1.62, 95%CI=1.17-2.24). In conclusion, the results of this meta-analysis suggest that the IL-17A -197G>A polymorphism contributes to an increased risk of human digestive cancer, both in the Asian and Caucasian populations and especially for gastric cancer.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.6
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• pp.3015-3020
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• 2016

Background: Numerous studies have investigated associations of DNA methyltransferase (DNMT) -149 C>T and -579 G>T polymorphisms with gastric cancer (GC) and colorectal cancer (CRC) susceptibility; however, the findings are inconsistent prompting the present meta-analysis. Materials and Methods: Related studies were identified from PubMed, Google scholar, and SID until 10 October 2015. Pooled odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the strength of the associations. Results: Eleven studies were included based on the search criteria for CRC and GC related to the DNMT3B 149 C>T (3,353 cases and 4,936 controls) and DNMT3B 579 G>T (1,387 cases and 2,064 controls) polymorphisms. There was no significant association overall between DNMT3B -149 and 579 polymorphisms and the risk of cancer. In the stratified analysis by cancer type, DNMT3B 579G>T polymorphism was associated with the risk of CRC and GC. While the DNMT3B -149C/T polymorphism was related with a significantly increased risk of CRC in two tested models, dominant (GG+GT vs. TT: OR 0.51, 95 % CI 0.38-0.69; P = 0.00, Pheterogeneity=0.69, $I^2=0%$) and heterozygote (GT vs. TT: OR 0.50, 95 % CI 0.37-0.69; P=0.00, Pheterogeneity=0.41, $I^2=0%$), no evidence of any association with GC risk was observed as in the pooled analyses. Conclusions: More studies are needed to assess associations of DNMT3B -149C/T and DNMT3B 579G>T polymorphisms with cancer in different ethnicities with large population sizes to generate comprehensive conclusions.