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In recent decades, the appearance of inflammation near the appendix in patients with distal ulcerative colitis (UC) has been highlighted. Many epidemiological studies have confirmed the link between appendectomy and decreased incidence of UC. However, the clinical significance of appendiceal orifice inflammation (AOI) or peri-appendiceal red patch (PARP) as a “skip lesion” in UC has not been well elucidated. In this review, we summarized the literature regarding AOI/PARP and the role of this lesion in relation to UC. Since the appendiceal “skip area” in UC was first described in 1958, several reports using histologic examination of colectomy specimens and colonoscopy have been published. AOI/PARP has been more frequently associated with distal, mild UC than extensive, severe disease. Although it is still controversial, AOI/PARP seems to have little prognostic implication in the disease course of UC, including remission, relapse and proximal disease extension. However, some case reports have raised the possibility of a relationship between AOI/PARP and appendiceal neoplasms such as appendiceal cystadenoma and appendiceal adenocarcinoma. In addition, some investigators have treated UC patients who were resistant to conventional medical therapy with appendectomy and have reported inconsistent therapeutic effect. Further research may lead to the discovery of etiologic and pathogenic roles of appendiceal inflammation in UC.  相似文献   
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One problem that may arise in full‐coverage restorations is clinical crown fracture. Fracture of an endodontically treated and crowned tooth in the esthetic zone may be embarrassing to both the patient and clinician. If a completely sound margin and at least 2 mm of coronal structure remain, a fractured tooth may possibly be retreated by a repair. Several methods have been introduced to reproduce the original contour of the tooth for retrofitting an existing crown. If an existing crown is used as a template, excessive core material may remain over the margin, as loading the proper amount of core material is difficult, and making vent holes on the existing crown is not feasible. This article presents a repair technique to reuse an existing crown with computer‐aided design and computer‐aided manufacturing (CAD/CAM) technology. By using a milled poly(methylmethacrylate) matrix, the mentioned limitations are eliminated, and the original contour of the tooth can be effectively restored with minimal intervention. As an existing crown is reused, the issues of additional time and cost for repreparation, reimpression, and new crown are eliminated.  相似文献   
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The aim of this study was to evaluate whether contrast enhanced fluid attenuated inversion recovery (CE-FLAIR) imaging can be used to predict the severity of meningitis based on leptomeningeal enhancement (LE) score and cerebrospinal fluid signal intensity (CSF-SI) on CE-FLAIR. We retrospectively analyzed data collected from 43 consecutive patients admitted to our hospital due to meningitis. Clinical factors including initial Glasgow Coma Scale (GCS) score, CSF glucose ratio, log CSF protein, log CSF WBC, and prognosis were evaluated. The LE score was semi-quantitatively scored, and we evaluated CSF-SI ratio at the interpeduncular or quadrigerminal cisterns on CE-FLAIR. We evaluated the differences in clinical variables, LE scores and CSF-SI ratios between the recovery and the complication group. We assessed the correlation between clinical variables, LE scores and CSF-SI ratios. The values of log CSF protein, CSF-SI ratio, and LE score were significantly higher in the complication group (p value <0.05). GCS score and CSF glucose ratio were significantly lower in the complication group (p value <0.01). The LE scores had significant negative correlation with GCS scores and CSF glucose ratios (p value <0.001). The LE score was significantly positively correlated with the value of log CSF protein and CSF-SI ratio (p value <0.01). The CSF-SI ratio was negatively correlated with GCS score and CSF glucose ratio (p value <0.01). The CSF-SI ratio was positively correlated with the value of log CSF protein (p value <0.05). Our results suggest that LE score and CSF-SI ratio are well correlated with clinical prognostic factors. We may predict the clinical severity of meningitis by using LE scores and CSF-SI ration on CE-FLAIR imaging.  相似文献   
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To effectively suppress porcine endogenous retroviruses (PERV)s, RNAi technique was utilized. RNAi is the up‐to‐date skill for gene knockdown which simultaneously multitargets both gag and pol genes critical for replication of PERVs. Previously, two of the most effective siRNAs (gag2, pol2) were found to reduce the expression of PERVs. Concurrent treatment of these two siRNAs (gag2+pol2) showed knockdown efficiency of up to 88% compared to negative control. However, despite the high initial knockdown efficiency 48 h after transfection caused by siRNA, it may only be a transient effect of suppressing PERVs. The multitargeting vector was designed, containing both gag and pol genes and making use of POL II miR Expression Vector, which allowed for persistent and multiple targeting. This is the latest shRNA system technique expressing and targeting like miRNA. Through antibiotics resistance characteristics utilizing this vector, miRNA‐transfected PK15 cells (gag2‐pol2) were selected during 10 days. An 88.1% reduction in the level of mRNA expression was found. In addition, we performed RT‐activity analysis and fluorescence in situ hybridization assay, and it demonstrated the highest knockdown efficiency in multitargeting (gag2+pol2) miRNA group. Therefore, according to the results above, gene knockdown system (siRNA and shRNA) through multitargeting strategy could effectively inhibit PERVs.  相似文献   
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Background/AimsAlthough pediatric ulcerative colitis (UC) has a different phenotype and clinical course than adult UC, its clinical features and outcomes are poorly defined, especially in Asian populations. This study investigated the clinical features and long-term outcomes of pediatric UC in a Korean population.MethodsWe retrospectively analyzed 208 patients aged <18 years diagnosed with UC between 1987 and 2013. The patient characteristics at diagnosis according to the Paris classification and the clinical course were analyzed.ResultsThe male-to-female ratio was 1.31, and the median patient age was 15.5 years. At diagnosis, 28.8% of patients had proctitis (E1), 27.8%, left-sided colitis (E2); 5.2%, extensive colitis (E3); and 38.2%, pancolitis (E4). The cumulative probabilities of extension after 5, 10, 15, and 20 years were 32.7%, 40.4%, 52.5%, and 65.8%, respectively. Eighteen patients underwent colectomy, and three patients had colorectal cancer. The cumulative probabilities of colectomy after 5, 10, 15, and 20 years were 7.1%, 8.9%, 12.6%, and 15.6%, and those of colorectal cancer after 10, 15, and 20 years were 0%, 2.1%, and 12.0%, respectively. The disease extent, Pediatric Ulcerative Colitis Activity Index severity, and systemic corticosteroid therapy were significant risk factors for colectomy. The development of primary sclerosing cholangitis was significantly associated with colorectal cancer.ConclusionsThis study provides detailed information on the disease phenotype and long-term clinical outcomes in a large cohort of Korean children with UC. They have extensive disease at diagnosis, a high rate of disease extension, and a low rate of cumulative colectomy.  相似文献   
59.
Background/AimsThe long-term course of Crohn’s disease (CD) has never been evaluated in non-Caucasian population-based cohorts. The aim of the present study was to evaluate the long-term prognosis of Korean CD patients in the well-defined population-based Songpa-Kangdong inflammatory bowel disease cohort.MethodsOutcomes of disease and their predictors were evaluated for 418 patients diagnosed with CD between 1986 and 2015.ResultsDuring a median of 123 months, systemic corticosteroids, thiopurines, and anti-tumor necrosis factor (TNF) agents were administered to 58.6%, 81.3%, and 37.1% of patients, respectively. Over time, the cumulative probability of starting corticosteroids significantly decreased (p=0.001), whereas that of starting thiopurines and anti-TNFs significantly increased (both p<0.001). The cumulative probability of behavioral progression was 54.5% at 20 years, and it significantly decreased during the anti-TNF era. Intestinal resection was required for 113 patients (27.0%). The cumulative probabilities of intestinal resection at 1, 5, 10, 20, and 25 years after CD diagnosis were 12.7%, 16.5%, 23.8%, 45.1%, and 51.2%, respectively. Multivariable Cox regression analysis identified stricturing behavior at diagnosis (adjusted hazard ratio [aHR], 2.70; 95% confidence interval [CI], 1.55 to 4.71), penetrating behavior at diagnosis (aHR, 11.15; 95% CI, 6.91 to 17.97), and diagnosis of CD during the anti-TNF era (aHR, 0.51; 95% CI, 0.35 to 0.76) as independently associated with intestinal resection. The standardized mortality ratio among CD patients was 1.36 (95% CI, 0.59 to 2.68).ConclusionsThe long-term prognosis of Korean patients with CD is at least as good as that of Western CD patients, as indicated by the low intestinal resection rate. Moreover, behavioral progression and intestinal resection rates have decreased over the past 3 decades.  相似文献   
60.
BACKGROUND: Primary Ewing's sarcoma-primitive neuroectodermal tumor (ES-PNET) of the uterus is an extremely rare malignancy. CASE: A 30-year-old Korean woman presented with abnormal uterine bleeding with uterine enlargement. A computed tomography (CT) scan and magnetic resonance imaging (MRI) of the abdomen and pelvis showed a huge uterine mass measuring 18 x 20 x 21 cm, metastasis to both pelvic and para-aortic lymph nodes, and omental infiltration. The pathology report of the uterine mass described a uniformly hypercellular tumor, which was arranged in diffuse solid sheets of uniform, small, rounded, and sometimes spindle-shaped cells, with scanty cytoplasm. Immunohistochemically, the mass tested positive for vimentin, CD99, and chromogranin. The patient received several courses of combination chemotherapy and radiotherapy but died from tumor progression 16 months after the initial diagnosis. CONCLUSION(S): This is a rare case of primary uterine ES-PNET in a woman of reproductive age. A review of the literature indicates that primary uterine ES-PNET requires early diagnosis and multimodality treatment including surgery, chemotherapy, and radiotherapy. The behavior of this tumor is potentially aggressive.  相似文献   
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