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41.
42.
Min Soo Choo Sung Yong Cho Kyungtae Ko Chang Wook Jeong Seung Bae Lee Ja Hyeon Ku Sung Kyu Hong Seok-Soo Byun Cheol Kwak Hyeon Hoe Kim Sang Eun Lee Hyeon Jeong 《World journal of urology》2014,32(6):1401-1409
Purpose
We investigated the influence of positive surgical margins (PSMs) and their locations on biochemical recurrence (BCR) according to risk stratification and surgical modality.Methods
A total of 1,874 post-radical-prostatectomy (RP) patients of pT2–T3a between 2000 and 2010 at three tertiary centers, and who did not receive neoadjuvant/adjuvant therapy, were included in this study. Patients were stratified according to BCR risk: low risk (PSA <10, pT2a-b, and pGS ≤6), intermediate risk (PSA 10–20 and/or pT2c and/or pGS 7), and high risk (PSA >20 or pT3a or pGS 8–10). The median follow-up was 43 months.Results
PSMs were a significant predictor of BCR in both the intermediate- and high-risk-disease groups (P = .001, HR 2.1, 95 % CI 1.3–3.4; P < .001, HR 2.8, 95 % CI 2.0–4.1). Positive apical margin was a significant risk factor for BCR in high-risk disease (P = .003, HR 2.0, 95 % CI 1.2–3.3), but not in intermediate-risk disease (P = .06, HR 1.7, 95 % CI 0.9–3.1). Positive bladder neck margin was a significant risk factor for BCR in both intermediate- and high-risk disease (P < .001, HR 5.4, 95 % CI 2.1–13.8; P = .001, HR 4.5, 95 % CI 1.8–11.4). In subgroup analyses, robotic RP provided comparable BCR-free survival regardless of risk stratification. Patients with PSMs showed similar BCR-free survival between open and robotic RP (log-rank, P = .897).Conclusions
Post-RP PSMs were a significantly independent predictor of disease progression in high-risk disease as well as intermediate-risk disease. Both positive apical and bladder neck margins are also significant risk factors of BCR in high-risk disease. Patients with PSMs showed similar BCR-free survival between open and robotic surgery. 相似文献43.
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46.
Keum-Seob Byun Won Jae Choi Ha-Young Lee Min-Ji Sim Sang-Ho Cha Jong-Chan Lee 《RSC advances》2018,8(69):39432
Herein, we discuss the effect of electron density in a furan pendant group on the thermally reversible Diels–Alder (DA) reaction based self-healing efficiency in polymethacrylate derivatives. First, the furan-functionalized polymethacrylates (rPFMA and dPFMA) having different electron density in the furan pendant groups were prepared through free-radical polymerization. The healing efficiency of rPFMA, which was expected to have high healing efficiency due to the high reactivity of DA reaction originating from the electron density in the furan moiety, was shown to be 95.89% in the first and 69.86% in the second healing process, respectively, where it is higher than that of dPFMA having relatively low electron density in the furan moiety. To illustrate these results, kinetic tests of the DA reaction for rPFMA64 and dPFMA64 were performed, where the reactivity of the DA reaction for rPFMA64 was much higher than that for dPFMA64. This could be explained by the electron density in the furan pendant groups which controls the reactivity of DA reaction having a major effect on the efficiency of self-healing performance in furan-functionalized polymethacrylates.Herein, we discuss the effect of electron density in a furan pendant group on the thermally reversible Diels–Alder (DA) reaction based self-healing efficiency in polymethacrylate derivatives. 相似文献
47.
Jo Jae-Cheol Kim Seok Jin Lee Ho Sup Eom Hyeon-Seok Lee Soon Il Park Yong Lee Jeong-Ok Lee Yoojin Yhim Ho-Young Yang Deok-Hwan Byun Ja Min Kang Hye Jin Kim Hyo Jung Shin Ho-Jin Yoo Kwai Han Suh Cheolwon 《Annals of hematology》2020,99(2):223-228
Annals of Hematology - Limited-stage (Ann Arbor stage I or II) mantle cell lymphoma (MCL) is an extremely rare disease. Thus, there is little data on the clinical features and treatment outcomes of... 相似文献
48.
Joseph W. Pittman Anand Navalgund Steve H. Byun Hechang Huang Albert H. Kim Do-Gyoon Kim 《Clinical oral investigations》2014,18(3):721-728
Objectives
The objective of this study was to examine whether cortical bone thickness and bone mineral density (BMD) can explain the primary migration of a mini-implant under a functional orthodontic tangential loading at the early stage following implantation.Materials and methods
Mini-implants were installed in human mandibular sections. A constant tangential load (2 N) was applied to the mini-implant under hydration. Creep, which is a time-dependent viscoelastic displacement in the bone surrounding the mini-implant, was assessed as the change in displacement during 2 h of loading. The total migration was measured as a maximum displacement that combined an initial elastic displacement and creep. After removal of the mini-implant, all specimens were scanned together by cone beam computed tomography. Cortical bone thickness and BMD were measured for the bone voxels surrounding the implant site.Results
BMD had significant correlations with the displacement parameters (p?<?0.019), but the cortical bone thickness did not (p?>?0.272). Permanent bone deformation adjacent to the implant was observed to be resulting from substantial creep development under the orthodontic functional loading level.Conclusions
BMD controls the primary migration of the mini-implant system in mandibular bone. Viscoelastic creep can develop at a small constant functional loading level, leading to migration of the mini-implant.Clinical relevance
The current results indicated that mini-implant migration can develop under the small level of functional orthodontic load used in clinic. If the active bone remodeling around the mini-implant accelerates the migration, the risk of causing damage in vital organs next to the mini-implant increases. 相似文献49.
Hydrogenation of biomass-derived furfural is an important process in biofuel production. Herein, different Pt-supported TiO2 morphologies: nanorod (NR), nanoparticle (NP), and hollow microsphere (HMS) were prepared by the impregnation–chemical reduction method. The furfural conversion increased with an increase of Pt dispersion. However, cyclopentanone selectivity was affected by TiO2 properties, the strong metal–support interaction (SMSI) effect, and the reaction conditions. The Pt/TiO2 NR catalyst exhibited the highest cyclopentanone selectivity of 50.4%. Based on the H2-temperature programmed desorption (H2-TPD) and X-ray photoelectron spectroscopy (XPS) results, the Pt/TiO2 NR catalyst showed a SMSI effect, which was introduced by the chemical reduction method. We suggest that electron charge transfer from Ti species to Pt in the Pt/TiO2 NR catalyst affects the cyclopentanone selectivity by controlling the adsorption strength between the reactant and the Pt surface, thus retarding the formation of byproducts.Hydrogenation of biomass-derived furfural is an important process in biofuel production. 相似文献
50.
Wendling Adam L. Byun Sharon Y. Koenig Megan Vasilopoulos Terrie 《Archives of gynecology and obstetrics》2020,301(1):179-187
Archives of Gynecology and Obstetrics - Oral carbohydrate consumption before surgery improves insulin sensitivity, cardiac output and well-being, and shortens hospital stays without adverse... 相似文献