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21.
Hye Suck An Jae Kwon Cho Kyong Min Kim Maeng Hyun Son Jeong In Myeong Chul Min An 《Conservation Genetics Resources》2014,6(3):665-667
Seven-band grouper, Epinephelus septemfasciatus, is of considerable economic value and a candidate species of aquaculture in Eastern Asia. It is necessary to monitor the stocks for the sustainable use and aquaculture of the species. Monitoring genetic variation among marine resources necessitates the development of genetic markers. Here, we report 22 polymorphic microsatellite markers with 2–16 alleles per locus. The mean observed and expected heterozygosity per locus was 0.53 and 0.57, respectively. Cross-amplification revealed variability in Epinephelus bruneus and Epinephelus akaara. The 22 markers developed can be a valuable tool for genetic conservation of this species. 相似文献
22.
Kim Jung Wan Eom Youngsub Chung Hyun Woo Song Jong Suk Jeong Ji Won Park Seh Kwang Kim Hyo Myung 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2020,258(8):1735-1743
Graefe's Archive for Clinical and Experimental Ophthalmology - This study was conducted to investigate factors related to postoperative good near and distance visual outcomes in the Lentis... 相似文献
23.
Seung-Hyun Jin Chun Kee Chung Jeong Eun Kim Young Doo Choi 《Journal of Korean Neurosurgical Society》2014,56(6):455-462
ObjectiveTo propose a new measure for effective monitoring of intraoperative somatosensory evoked potentials (SEP) and to validate the feasibility of this measure for evoked potentials (EP) and single trials with a retrospective data analysis study.MethodsThe proposed new measure (hereafter, a slope-measure) was defined as the relative slope of the amplitude and latency at each EP peak compared to the baseline value, which is sensitive to the change in the amplitude and latency simultaneously. We used the slope-measure for EP and single trials and compared the significant change detection time with that of the conventional peak-to-peak method. When applied to single trials, each single trial signal was processed with optimal filters before using the slope-measure. In this retrospective data analysis, 7 patients who underwent cerebral aneurysm clipping surgery for unruptured aneurysm middle cerebral artery (MCA) bifurcation were included.ResultsWe found that this simple slope-measure has a detection time that is as early or earlier than that of the conventional method; furthermore, using the slope-measure in optimally filtered single trials provides warning signs earlier than that of the conventional method during MCA clipping surgery.ConclusionOur results have confirmed the feasibility of the slope-measure for intraoperative SEP monitoring. This is a novel study that provides a useful measure for either EP or single trials in intraoperative SEP monitoring. 相似文献
24.
Se Kyung Lee Seok Won Kim Sang-Ah Han Won Ho Kil Jeong Eon Lee Seok Jin Nam 《World journal of surgery》2014,38(5):1065-1069
Background
Epidemiologic studies showed that the experience of pregnancy is associated with a reduced risk of breast cancer. We hypothesized that parity may differentially be associated with the development of invasive breast cancer by each subtype.Methods
We reviewed the clinical, radiological, and pathological records of women diagnosed with invasive ductal carcinoma of the breast at Samsung Medical Center between 2005 and 2009. Clinicopathologic results were assessed by χ2 and Fisher’s exact tests with a Bonferroni correction for categorical variables, and by the Kruskal–Wallis test for nonparametric continuous variables. A multinomial logistic regression model was used for multivariate analysis.Results
Among a total of 3,095 patients, 283 (9.14 %) patients were nulliparous. Older age, higher pN, and expression of HER2 were associated with parity. In the analysis between parity and molecular subtypes, parity also had a variable influence on breast cancer subtypes (p = 0.032). Intergroup analysis with multiple comparison showed that luminal B subtype was related to nulliparity compared with HER2-positive subtypes (p = 0.03).Conclusions
The effect of parity on the development of breast cancer differed by hormone receptor and HER2 expression. It seems that parity might have a protective effect against hormone receptor-positive breast cancer, especially cancers expressing HR+ and Ki-67. Further basic research to define and understand this result is ongoing. 相似文献25.
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26.
27.
28.
Hee-Jung Yun Jin-Sun Jeong Nan-Sim Pang Il-Keun Kwon Bock-Young Jung 《The journal of advanced prosthodontics》2014,6(3):171-176
PURPOSE
The aim of this study was to determine the absolute value of the root/crown ratio (R/C ratio) using panoramic radiographs (PRGs) in a healthy Korean population.MATERIALS AND METHODS
In total, 99 patient radiographs (of 50 males and 49 females subjects; aged 16 to 24 years old) were examined, and 2,770 teeth were analyzed. Crown lengths and root lengths were measured with modified Lind''s measurements using PACS tools by two examiners in two separate sessions two months apart. All data were analyzed using SPSS. The independent t-test was used to assess for gender differences, and the paired t-test was used to compare both arches with a significance level of P<.05.RESULTS
The mean R/C ratios varied from 1.29 to 1.89 (male: 1.28-1.84; females: 1.31-1.94). The highest R/C ratios were recorded for the mandibular canines (1.89), followed by the maxillary canines (1.79). The lowest R/C ratios were recorded for the maxillary second molars (1.31). In comparison with the maxillary teeth (1.29-1.78), the mandibular teeth yielded the higher R/C ratio (1.47-1.89), and this difference was significant in the females (P<.05). The difference between the genders was not statistically significant, except for the maxillary central incisors, mandibular canines and mandibular first premolars.CONCLUSION
These data may enhance the understanding of the clinical R/C ratio as a useful guideline for determining the status of teeth and the ethnic difference. 相似文献29.
Joonwoo Jeong Zoey S. Davidson Peter J. Collings Tom C. Lubensky A. G. Yodh 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(5):1742-1747
Confined liquid crystals (LC) provide a unique platform for technological applications and for the study of LC properties, such as bulk elasticity, surface anchoring, and topological defects. In this work, lyotropic chromonic liquid crystals (LCLCs) are confined in spherical droplets, and their director configurations are investigated as a function of mesogen concentration using bright-field and polarized optical microscopy. Because of the unusually small twist elastic modulus of the nematic phase of LCLCs, droplets of this phase exhibit a twisted bipolar configuration with remarkably large chiral symmetry breaking. Further, the hexagonal ordering of columns and the resultant strong suppression of twist and splay but not bend deformation in the columnar phase, cause droplets of this phase to adopt a concentric director configuration around a central bend disclination line and, at sufficiently high mesogen concentration, to exhibit surface faceting. Observations of director configurations are consistent with Jones matrix calculations and are understood theoretically to be a result of the giant elastic anisotropy of LCLCs.The director configurations of confined liquid crystals exhibit a rich phenomenology, the physics of which is determined by a delicate interplay of topology, elastic free energy, and anchoring conditions at the boundaries (1–12). Droplets present arguably the simplest and most symmetric confining container for liquid crystals. Droplets of thermotropic liquid crystals (TLCs) and the manipulation of their director configurations, for example, are actively studied, in part because of their demonstrated use as core materials in display technologies (3, 13) and their potential applications ranging from biosensors (14, 15) to microlasers (16). Indeed, significant fundamental and technological progress has been made with TLC droplets, because their bulk elasticity and surface anchoring phenomena are now well understood and easily controlled.Lyotropic chromonic liquid crystals (LCLCs) are composed of organic, charged, and plank-like mesogens that self-assemble in water into columnar aggregates via noncovalent electrostatic, excluded volume, hydrophobic, and pi–pi stacking interactions (17–20). The aggregates, in turn, assemble into nematic or columnar phases, depending on temperature and concentration. A variety of organic molecules such as dyes, drugs, and biomolecules form LCLCs (17–28). However, far less is known about the fundamental science and applications potential of LCLCs than the more-studied TLCs. Indeed, basic properties of LCLCs, including aggregate size distribution and formation dynamics, bulk elasticity, and surface anchoring are neither fully characterized nor understood and are the subject of exciting ongoing research. Only recently, for example, have measurements been made of fundamental properties, such as the Frank–Oseen elastic constants (28, 29), of any LCLC, and they have revealed unusual concentration and temperature dependences of the splay and bend moduli and a twist modulus that is unusually small compared with the other two.Here, we explore the behavior of aqueous LCLCs droplets suspended in a background oil phase. The droplets provide an excellent platform for the study of basic LCLC properties because of their highly symmetric finite-volume confining geometry and, usually, their uniform boundary conditions. Our study investigates droplets similar to those in “classic” thermotropic LCs for which bulk elasticity and anchoring are easily characterized. Further, droplet size is more easily controlled in the water-in-oil emulsions than in systems at nematic–isotropic coexistence studied in previous work (9, 30–32). In particular, the water-in-oil emulsion system permits independent control of the continuous background phase into which one can add chemicals such as surfactants and through which one can regulate LCLC concentration to create isotropic, nematic, and columnar LCLC phases within the same drop.Specifically, we investigate configurations of Sunset Yellow FCF (SSY) LCLCs in surfactant-stabilized spherical water droplets. The experiments reveal a variety of unusual droplet types arising from nematic LCLCs'' very small twist modulus, from their room-temperature columnar phase, and from the planar anchoring of their aggregates at an oil–water interface. In the nematic phase, the director adopts a chiral-symmetry-breaking, twisted-bipolar configuration with an extraordinarily large twist revealed by polarized optical microscopy (POM). These droplets provide an archetypical example of an exotic structure that can be produced by the combination of geometric frustration and giant elastic anisotropy. In droplets of the columnar phase, which occurs at higher mesogen concentration, columns wrap in concentric circles around a central director disclination line while retaining their lattice structure. Interestingly, the lattice structure causes surface faceting of the soft boundary as the mesogen concentration is further increased. 相似文献
30.