• Journal of Chest Surgery
• /
• v.25 no.3
• /
• pp.335-340
• /
• 1992

Truamatic aortic rupture is usually fatal if left untreated. Prompt diagnosis is the cornerstone of suscessful management. But the usual screening tests are non specific and the accuracy of computerized tomography is low, Aortography which is a time consuming procedure may result in false-positive interpretations and significant morbidity. Recently transesophageal echocardiography provides a rapid, effective and relatively safe means of evaluating the distal aortic arch and also affords the opportunity to evaluate the heart during the same study, which may be of benefit in cases of suspected cardiac injury. The experience with the traumatic aortic ruptured patient and a critical review of the literature suggests that transesophageal echocardiography is a useful technique for the diagnosis of ruptured aorta following blunt chest trauma.

• The Korean Journal of Cytopathology
• /
• v.7 no.1
• /
• pp.51-58
• /
• 1996

The cytologic samples of 26 ovarian cystic lesions from 25 women, aspirated under guide by trans-vaginal ultrasound, were evaluated for clinicopathologic correlation. Clinically 20 women were seeking medical assistance for infertility problems, and trans-vaginal cyst aspiration was done during follow-up of ovulation induction. Among them seven cases were histologically confirmed. Twenty cases of "benign cyst" in cytologic diagnosis were follicullar cyst and two cases of "endometriotic cyst" in cytology were histologically also proven in one case. One false positive diagnosis was given to corpus luteum cyst. It is emphasized that because the cysts are aspirated transvaginally and mature squamous epithelial cells occasionally could be mixed in the sample, attention should be given not to diagnose such cases as mature cystic teratoma. According to this study. ovarian aspiration cytology is useful in the management of cystic ovarian lesions, particularly in young women.

• The Bulletin of The Korean Astronomical Society
• /
• v.46 no.2
• /
• pp.44.2-44.2
• /
• 2021

Detecting lensed quasar systems and estimating their time delays using the unresolved joint light curves can be the next frontier among the cosmological probes in the near future. One can get the independent measurement of the Hubble constant from the time delays but without requiring the systems to be resolved a priori followed by monitoring the image light curves using high-resolution telescopes for years. In this work, we propose a novel technique that can identify lensed quasars only using the observed unresolved light curves and without assuming a template or any prior information. Following a set of conservative selection criteria that gives zero false-positive outcome, we can accurately estimate the time delay for almost all the lensed systems with marginal noise in the data. For the case of noisy data, our approach can still correctly identify a substantial number of lensed systems with high certainty and measure the time delay accurately.

• Journal of Yeungnam Medical Science
• /
• v.14 no.2
• /
• pp.393-398
• /
• 1997

An accurate early diagnosis of congenital midgut malrotation is essential to prevention of catastrophic effects of volvulus. To evaluate the usefulness of radiologic examinations in diagnosing intestinal malrotation, we retrospectively analyzed radiologic findings and operation records of 17 intestinal malrotation patients, who were radiologically diagnosed. The age range of the patients studied were from 1day to 12years. The presenting symptoms were vomiting, vomiting with abdominal pain, abdominal distention, diarrhea and failure to thrive. The viewpoints of this analysis were the location of duodeno-jejunal flexure on barium meal and cecal location on barium enema. Sixteen of 17 patients, who were radiologically diagnosed, were surgically proven, but one patient with annular pancreas was false positive. In the case of 3 surgically proved patients, malrotation was suspected on barium meal prior to the barium enema, but final diagnosis was determined on barium enema examination. We concluded that a barium enema should be performed on all children with suspected malrotation where the initial upper gastro-intestinal study was normal or suspicious on account of the small incidence of false positive and false negative barium meals.

• Proceedings of the Korean Institute of Intelligent Systems Conference
• /
• 2003.09a
• /
• pp.559-562
• /
• 2003

A motion-based background subtraction method without geometric computation is proposed, allowing that the camera is moving parallel to the ground plane with uniform velocity. The proposed method subtracts the background region from a given image by evaluating the difference between calculated and model Hows. This approach is insensitive to small errors of calculated optical flows. Furthermore, in order to tackle the significant errors, a strategy for incorporating a set of optical flows calculated over different frame intervals is presented. An experiment with two real image sequences, in which a static box or a moving toy car appears, to evaluate the performance in terms of accuracy under varying thresholds using a receiver operating characteristic (ROC) curve. The ROC curves show, in the best case, the figure-ground segmentation is done at 17.8 ％ in false positive fraction (FPF) and 71.3％ in true positive fraction (TPF) for the static-object scene and also at 14.8％ in FPF and 72.4％ In TPF for the moving-object scene, regardless if the calculated optical flows contain significant errors of calculation.

• The Korean Journal of Nuclear Medicine
• /
• v.21 no.1
• /
• pp.61-68
• /
• 1987

Investigation with $^{57}Co-Bleomycin$ in patients with the various cancers and in tumor bearing animals are descirbed. In the patients, $^{57}Co-Bleomycin$ appears to be one of the useful tumor-seeking radiopharmaceuticals, and worth applicable to clinical uses. Labelled yield of $^{57}Co-Bleo$ was about 97 % by thin layer chromatography. The pyrogen free tests were performed to meet U.S.P. critical ranges. In clinical studies with $^{57}Co-Bleo$, 4 cases out of 5 patients with lung cancer., 2 cases among 3 thyroid cancer patients, and all 3 hepatoma patients showed positive tumor scans. The patients with stomach cancer, and the esophageal cancer showed false negative scintigraphy. A case with pulmonary tuberculosis showed a positive scan while liver abscess showed a negative picture. The merits of $^{57}Co-Bleomycin$ scintigraphy seems to be its relatively high affinity to tumors and low radiation hazard in spite of long physical half life.

• Korean Journal of Head & Neck Oncology
• /
• v.31 no.1
• /
• pp.9-13
• /
• 2015

Fine needle aspiration cytology as a diagnostic workup of parotid gland tumor is a simple and useful method. Although fine needle aspiration cytology could not predict accurate diagnosis in all cases, it is usually helpful in differentiating malignancy and benign lesions. A 35-year-old female was found to have a parotid mass for 1 year. Preoperative evaluation including computed tomography and magnetic resonance imaging were non-diagnostic, but, fine needle aspiration cytology on parotid mass showed the suspicion of a low-grade mucoepidermoid carcinoma. Superficial parotidectomy and selective neck node dissection were done based on cytology. However, final pathological examination confirmed benign pleomorphic adenoma. Here, the diagnostic accuracy and cautions in interpretation of result of fine needle aspiration cytology is discussed with respect to the case.

• Proceedings of the Korean Statistical Society Conference
• /
• 2004.11a
• /
• pp.195-198
• /
• 2004

One Important problem in a cancer microarray study is to identify a set of genes from which a molecular prognostic indicator can be developed. In parallel with this problem is to validate the chosen set of genes. We develop in this note a K-fold cross validation procedure by combining a 'pre-validation' technique and a bootstrap resampling procedure in the Cox regression . The pre-validation technique predicts the microarray predictor of a case without having seen the true class level of the case. It was suggested by Tibshirani and Efron (2002) to avoid the possible over-fitting in the regression in which a microarray based predictor is employed. The bootstrap resampling procedure for the Cox regression was proposed by Sauerbrei and Schumacher (1992) as a means of overcoming the instability of a stepwise selection procedure. We apply this K-fold cross validation to the microarray data of 92 gastric cancers of which the experiment was conducted at Cancer Metastasis Research Center, Yonsei University. We also share some of our experience on the 'false positive' result due to the information leak.

• International journal of advanced smart convergence
• /
• v.12 no.1
• /
• pp.82-91
• /
• 2023

In 2020 when the COVID-19 pandemic began in full-scale, the WHO Director-General warned of the dangers of an infodemic. The infodemic is a phenomenon in which false information spreads rapidly like an epidemic and causes chaos, and it was noted that the COVID-19 pandemic is not just limited to health problems, but also linked to a variety of issues such as human rights, economic inequality, various discrimination, hate speech, fake news, global governance etc. In the field of education, it is necessary to think about how to connect this global situation with school classes. Accordingly, this study suggested the direction for global citizenship education by analyzing how the infodemic spreads on Korean social media with the case of the recent global COVID-19 pandemic. According to the research results, the rate of negative emotions was higher than positive ones in the emotions that generate infodemic, while anxiety and anger were focused among negative emotions. In addition, the infodemic tended to spread widely with the feelings of anger rather than anxiety, and the feelings of anger led to advocating aggressive policies against certain country and regions. Therefore, global citizenship education is required to focus on a sense of duty and responsibility as a citizen, not on the level of national identity based on an exclusive sense of belonging. Furthermore, global citizenship education needs to lead to presenting a blueprint for education in a way that can enhance the awareness of the global community for joint response to global challenges and realize common prosperity based on sustainability and justice.

• Clinical and Experimental Pediatrics
• /
• v.49 no.2
• /
• pp.162-166
• /
• 2006

Purpose : There are few reports in Korean literature on the diagnostic efficacy of fine needle aspiration cytology(FNAC) for pediatric cervical lymphadenopathy. This study examined the diagnostic value of FNAC on cervical lymphadenopathy in children. Methods : Data from 57 pediatric patients(aged 0.3 to 14 years) who underwent FNAC due to cervical lymphadenopathy between January 2001 and March 2005 was reviewed retrospectively. Results : Reactive cervical lymphadenitis was the most common result of the FNAC(52.5 percent). Malignant disease were revealed in 14 percent of all cases. The sensitivity, specificity was 86 percent and 96 percent, respectively. The positive and negative predictive values for malignant disease was 75 percent and 98 percent, respectively. There were two false-positive cases on FNAC; one case of Langerhans cell histiocytosis, and another with infectious mononucleosis. A false-negative case on FNAC was found to be acute lymphocytic leukemia. In seven cases(12 percent), the final diagnosis was confirmed by an open biopsy after the FNAC. There were four FNAC cases where the specimen was not satisfactory for making a diagnosis(7 percent). There were no serious complications of the FNAC procedure. Conclusion : FNAC had a high diagnostic efficacy for evaluating children with cervical lymphadenopathy.