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101.
Colorectal cancer is the second most common cancer in males and the fourth most common in females in Korea. Since the most of colorectal cancer occur through the prolonged transformation of adenomas into carcinomas, early detection and removal of colorectal adenomas are one of the most effective methods to prevent colorectal cancer. Considering the increasing incidence of colorectal cancer and polyps in Korea, it is very important to establish Korean guideline for colorectal cancer screening and polyp detection. Korean Multi-Society Take Force developed the guidelines with evidence-based methods. Parts of the statements drawn by systematic reviews and meta-analyses. Herein we discussed the epidemiology of colorectal cancers and adenomas in Korea, optimal screening methods for colorectal cancer, and detection for adenomas including fecal occult blood tests, radiologic tests, and endoscopic examinations.  相似文献   
102.
For InP-based QDs, the current technology does not outperform CdSe-based QDs in many respects, one of which is stability. The optical stability of QDs is closely related to their surface properties, so QDs often use organic ligands for surface protection. These organic ligands are dynamically attached and detached on the QD surface; during detachment, their surfaces are easily damaged and oxidized, thereby deteriorating their optical characteristics. Therefore, we have synthesized a ligand 1,2-hexadecanedithiol with a bidentate form, inducing one ligand to bind to the QD surface strongly through the chelate effect, as a good way to improve the stability of the QDs; thus, the PL stability of the green-light-emitting InP-based QDs was greatly increased. To confirm the existence of the dithiol ligand, we used thermogravimetric analysis/simultaneous thermal analysis-mass spectroscopy (TGA/STA-MS). After that, we applied the ligand to blue-light-emitting ZnSe QDs and red-light-emitting InP QDs, and for those two types of QD we also confirmed that the stability was increased. Additionally, we tested dithiol exchanged QDs at a high temperature of 150 °C, and the increase of stability was effective even in a high temperature condition.

For InP-based QDs, the current technology does not outperform CdSe-based QDs in many respects, one of which is stability.  相似文献   
103.
The halophilic bacterium Pseudoalteromonas phenolica is well known as a promising candidate that enables the recycling of organic wastes at high salinity. However, for industrial applications of P. phenolica further research is required to explore the biological mechanism for maximizing the activities and productivities of this bacterium. In this study, we investigated the osmotic stress resistance and specific protease activities of P. phenolica in a normal-salt medium (0.3 M NaCl) and high-salt medium (1 M NaCl) based on intra- and extracellular multi-omics approaches. Proteins related to betaine and proline biosynthesis were increased under high salt stress. The targeted metabolite analysis found that proline was overproduced and accumulated outside the cell at high salinity, and betaine was accumulated in the cell by activation of biosynthesis as well as uptake. In addition, extracellular serine proteases were shown to be upregulated in response to salt stress by the extracellular proteomic analysis. The specific proteolytic activity assay indicated that the activities of serine proteases, useful enzymes for the recycling of organic wastes, were increased remarkably under high salt stress. Our results suggest that betaine and proline are key osmoprotectant metabolites of P. phenolica, and they can be used for the improvement of protease production and P. phenolica activities for the recycling of high-salt organic wastes in the future.

Multi-omics study showed the osmoprotective mechanism and changes of proteolytic activities of Pseudoalteromonas phenolica in response to salt stress.  相似文献   
104.
Although many report intra‐operative cardiac arrests (ICAs) in liver transplantation (LT), the incidence, major causes, and outcome remain unclear. We aimed to investigate retrospectively, the incidence, nature, and outcome of ICA in Asian population and to identify risk factors for ICA. Consecutive 1071 LTs in an institution during 1996–2011 (adult 920, pediatric 151/living donor liver transplantation, LDLT 841, deceased donor liver transplantation, DDLT 230) were reviewed. ICA occurred in 14 adult LTs (1.5%), but none in pediatrics. ICA occurred 1.0% and 3.3% in LDLT and DDLT, respectively. Stages of ICA incidence were three at pre‐anhepatic, one at anhepatic, and 10 at neohepatic stage. Post‐reperfusion syndrome (PRS) with hyperkalemia and bleeding were the major causes of ICA. While LDLT showed miscellaneous causes for ICA at various stages, DDLT incurred ICAs at neohepatic stage only. Interestingly, we did not find pulmonary thromboembolism (PTE) to incur ICA. Risk factor analysis showed no association of pre‐operative patient condition, donor types, and intra‐operative parameters. In this review, the incidence of ICA was low in Asian population with LDLT predominance, and while PTE was not the cause of ICA, the neohepatic stage with PRS and bleeding was the most vulnerable period to anticipate ICA.  相似文献   
105.
Varus posteromedial rotatory instability refers to one of the complex elbow fracture-dislocation caused by anteromedial coronoid fracture with disruption of lateral collateral ligament (LCL). Recent clinical and biomechanical studies have demonstrated that this unstable complex injury resulted in incongruence of joint, which could lead to early posttraumatic arthritis. With reports of poor result after conservative treatment, surgical treatment including anteromedial fixation and LCL repair has been strongly recommended to achieve stable joint. This case series describes three patients with anteromedial coronoid fracture who were managed conservatively with excellent outcomes. This report suggests that anteromedial coronoid fracture associated with posteromedial rotatory instability might be treated using conservative treatment in selective cases when anteromedial coronoid fracture is minimally displaced and there is no evidence of elbow subluxation.  相似文献   
106.
107.

Purpose

We compared maximal diameters of ipsilateral (IMA) and contralateral (IMA) internal mammary arteries in patients with unilateral breast cancer and analyze the implications of enlargements of ipsilateral or contralateral IMAs in relation to histopathologic factors.

Materials and methods

Of 568 women who underwent breast magnetic resonance imaging (MRI) examinations from January 2009 to May 2012, 196 had unilateral, histologically proven breast cancer. In 156 women, maximal IMA diameters in the second intercostal space were measured by two blinded radiologists in left and right sides using nonenhanced axial T2-weighted turbo spin-echo sequence images.

Results

In the 156 study patients, mean maximal diameter of ipsilateral IMAs (2.37 ± 0.60 mm) was significantly larger than that of contralateral IMAs (2.03 ± 0.58 mm) (p = 0.00). Ipsilateral IMA enlargement was present in 66.7 % of the patients (104 of 156). Furthermore, ipsilateral IMA enlargement was found to be significantly associated with human epidermal growth factor receptor-2 (HER-2) expression (p = 0.039).

Conclusions

Maximal IMA diameter was significantly greater in ipsilateral sides in breast cancer patients. Findings suggest ipsilateral IMA enlargement detected by MRI might be a useful additional predictor of HER-2 expression in unilateral breast cancer.
  相似文献   
108.
The aim of the present study was to investigate the therapeutic mechanism of low-level laser therapy (LLLT) in the mouse tail lymphedema model. Six-week-old female mice were classified into the laser treatment group, sham treatment group, and surgical control group (10 mice per group). LLLT was administered daily for 10 min from the surgical day to 11 days (12 times). Macrophage activation and lymphatic vessel regeneration were evaluated through immunohistochemical staining with anti-F4/80 and anti-LYVE-1 antibodies, respectively, at 12 days post-procedure. Quantitative real-time polymerase chain reaction (qPCR) was performed to measure messenger RNA (mRNA) expression of vascular endothelial growth factor A, B, C, R1, R2, and R3 (VEGF-A, VEGF-B, VEGF-C, VEGFR1, VEGFR2, and VEGFR3) at 12 days post-procedure. Student’s t and one-way ANOVA tests were performed for statistical analyses. Significance was defined as p?<?0.05. The thickness of the tail rapidly increased until 6 days in the laser and sham groups. The mice in the laser group showed a significantly decreased thickness compared with the sham group at 10 and 12 days. Immunohistochemistry assay revealed that LLLT reduced inflammation and induced new lymphatic vessel growth. qPCR showed that expressions of VEGFR3 were (p?=?0.002) increased in the laser group. These results suggest that LLLT has anti-inflammatory and lymphangiogenetic effects for the management of lymphedema.  相似文献   
109.
110.
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