• 대한임상검사과학회지
• /
• 제55권3호
• /
• pp.132-142
• /
• 2023

서울대학교병원 진단면역검사실에서 HLA 형별 검사를 위한 결과 산출하는 과정에서 HLA-DR 검사 시행 건수 총 611건 중 Lot No.20의 시약에서 빈번히 나타나는 위양성과 위음성으로 의심되는 특이 bead 들의 반응을 발견하게 되었다. 따라서 정확한 결과 산출과정을 모색하기 위하여 특이 bead들의 cut-off 수정을 하지 않은 검사결과 533건과 특이 bead의 cut-off 수정을 한 뒤 결과 산출을 한 78건의 사례들을 가지고 cut-off 수정을 야기시키는 요인을 여러 변수로서 규명하고자 하였다. 검체대상의 인구통계특성과 cut-off 수정 여부를 확인하기 위해 빈도분석, 검사실의 습도를 변수로 넣어 기술통계를 진행하였고, cut-off 수정 여부와 인구통계특성의 연관성을 확인하기 위하여 교차분석을 시행, cut-off 수정 여부에 따른 습도의 차이를 검증하기 위해 독립표본 t검증을 실시하였다. 마지막으로 습도수준에 따른 cut-off 수정비율의 관계를 검증하기 위해 로지스틱 회귀분석을 실시하였다. 결과적으로 검사실의 습도 수준이 증가함에 따라 cut-off 수정사례는 0.986배 감소하는 것으로 나타났다. 이는 습도가 낮아질수록 cut-off 수정률이 증가한다는 것을 의미한다. 따라서 검사실의 습도 또한 HLA typing 결과에 영향을 미치는 요인임을 시사한다.

• Journal of Yeungnam Medical Science
• /
• 제15권1호
• /
• pp.143-150
• /
• 1998

3세대 EIA를 이용한 anti-HCV 검사는 2세대 EIA에 비해 예민도와 특이도가 향상되었으나, 여전히 제조회사간에 서로 상이한 결과를 보이는 경우가 많았다. 저자들은 국산 3세대 anti-HCV 검사 시약인 LG HCD 3.0과 기존 영남대학교 의과대학 부속병원에서 사용하고 있는 Axsym HCV version 3.0, Cobas Core anti-HCV EIA와 비교하였다. Cobas 키트가 분별력과 민감도는 높았으나 상대적으로 위양성률이 높은 경향을 보였다. LG 키트는 희석 검체에서 1례를 제외하고는 1:160까지 양성을 보였으며, 다른 두 종의 anti-HCV 키트와 우수한 일치율을 보였으나, 다른 두 키트에 비해 비교적 분별력이 낮아 양성의 50%에서 S/C가 5이하의 값을 보였다. 위양성을 보인 검체의 S/C는 1에서 4사이이고, 위음성을 보인 1례에서는 0.91로 나타나 S/C가 0.8에서 4사이인 경우 면역블로팅검사로 확인할 필요가 있다고 생각되므로 검체의 양성율과 사용목적을 고려하여 시약을 선정하여야 할 것이다.

• 대한두경부종양학회지
• /
• 제23권1호
• /
• pp.37-40
• /
• 2007

Objectives：Cutaneous angiosarcoma is an infrequent but aggressive neoplasm involving the skin of the face and scalp. Unfamiliarity with the clinical manifestations of cutaneous angiosarcoma frequently leads to misdiagnosis and delay in treatment. Complete surgical resection requires the performance of preoperative staging biopsies to determine the true extent of the neoplasm. Intraoperative frozen section analysis to determine the adequacy of the surgical resection is unreliable due to the high false negative rate. Material and Methods：In five scalp angiosarcoma cases, mapping biopsies were performed at far from the suspected edge of the neoplasm. On permanent pathology, we obtained tumor free margin with occasional focal involvement of the tumor. Results：Frozen-section analysis of the resected margins is inconclusive, for the subtle diagnostic features of angiosarcoma are distorted by the tissue processing required for frozen-section analysis. The characteristic dermal vessels lined by their malignant cells are collapsed by the freezing process. This results in a high rate of false-negative reports and possibly leads to incomplete resection of the neoplasm. Conclusion：Our recommendation is to establish the margins of the tumor by performing preoperative evaluations by mapping biopsies.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권4호
• /
• pp.1583-1588
• /
• 2012

Fine needle aspiration (FNA) cytology is well accepted as a safe, reliable, minimal invasive and cost-effective method for diagnosis of salivary gland lesions. This study evaluated the accuracy and diagnostic performance of FNA cytology in Thailand. A consecutive series of 290 samples from 246 patients during January 2001-December 2009 were evaluated from the archive of the Anatomical Pathology Department of our institution and 133 specimens were verified by histopathologic diagnoses, obtained with material from surgical excision or biopsy. Cytologic diagnoses classified as unsatisfactory, benign, suspicious for malignancy and malignant were compared with the histopathological findings. Among the 133 satisfactory specimens, the anatomic sites were 70 (52.6%) parotid glands and 63 (47.4 %) submandibular glands. FNA cytological diagnoses showed benign lesions in 119 cases (89.5 %), suspicious for malignancy in 3 cases (2.2 %) and malignant in 11 cases (8.3%). From the subsequent histopathologic diagnoses, 3/133 cases of benign cytology turned out to be malignant lesions, the false negative rate being 2.2 % and 1/133 case of malignant cytology turned out to be a benign lesion, giving a false positive rate was 0.8%. The overall accuracy, sensitivity, specificity, positive predictive value and negative predictive value were 97.0% (95% CI, 70.6%-99.4%), 81.3% (95% CI, 54.4%-96.0%), 99.1% (95% CI, 95.4%-100%), 92.9% (95% CI, 66.1%-99.8), 97.5% (95% CI, 92.8%-99.5%), respectively. This study indicated that FNA cytology of salivary gland is a reliable and highly accurate diagnostic method for diagnosis of salivary gland lesions. It not only provides preoperative diagnosis for therapeutic management but also can prevent unnecessary surgery.

• Clinical and Experimental Reproductive Medicine
• /
• 제32권3호
• /
• pp.223-230
• /
• 2005

Objective: This study was performed to evaluate the accuracy of hysterosalpingography (HSG) for evaluating female infertility patients by comparison with hysteroscopic and laparoscopic examination. Methods and Material: Total 219 infertile patients were retrospectively analyzed between January 1, 2002 and December 31, 2003. Ninety seven patients (44.3%) were primary infertility, 122 patients (55.7%) were secondary infertility. We performed hysteroscopic and laparoscopic examination on next cycle when HSG revealed any abnormal finding, and 3~6 cycles later if HSG was normal. Results: The accuracy of HSG was 65.2% compared with hysteroscopic examination (sensitivity 88.4%, specificity 46.4%, false positive rate 53.6%, false negative rate 11.6%). The most common abnormal finding of hysteroscopy was uterine synechia (67.4%) followed by endometrial polyp, uterine anomaly (e.g. uterine septum), endometrial hyperplasia. Compared with laparoscopic examination, the accuracy of HSG was 76.9% (sensitivity 98.9%, specificity 70.6%, +LR 3.36, -LR 0.02). The positive predictive value of normal patent tube was excellent (99.6%) but that of proximal tubal blockage was only 46.7%. The unilateral tubal obstruction of HSG was poor accuracy (+LR 3.85 -LR 0.68) and 70% of those was patent by laparoscopic examination. Laparoscopic examination also revealed that 53% of patients had peritubal adhesion and 37% of patients has additional pelvic findings, especially endometriosis. Among the patients had normal HSG, 53.5% patients with normal ultrasonography was diagnosed endometriosis (25.6% of them had endometriosis stage I-II). Conclusion: Normal HSG shows a high negative predictive value. Nevertheless, the incidence of associated pelvic disease in the normal HSG group is high enough to warrant diagnostic laparoscopy if nonsurgical treatment is unsuccessful. Because HSG has poor accuracy in predicting distal tubal blockage and peritubal adhesion, and poor positive predictive value of proximal tubal blockage, laparoscopic examination could be considered in abnormal HSG group.

• Journal of Trauma and Injury
• /
• 제31권3호
• /
• pp.151-158
• /
• 2018

Purpose: The regional emergency medical centers manage the patients with major blunt trauma according to the process appropriate to each hospital rather than standardized protocol of the major trauma centers. The primary purpose of this study is to evaluate the effectiveness and influence on prognosis of additional cervical-thoracic-lumbar-spine computed tomography (CTL-spine CT) scan in diagnosis of spinal injury from the victim of major blunt trauma with impaired consciousness. Methods: The study included patients visited the urban emergency medical center with major blunt trauma who were over 18 years of age from January 2013 to December 2016. Data were collected from retrospective review of medical records. Sensitivity, specificity, positive predictive value, and negative predictive value were measured for evaluation of the performance of diagnostic methods. Results: One hundred patients with Glasgow coma scale ${\leq}13$ underwent additional CTL-spine CT scan. Mechanism of injury was in the following order: driver, pedestrian traffic accident, fall and passenger accident. Thirty-one patients were diagnosed of spinal injury, six of them underwent surgical management. The sensitivity of chest, abdomen and pelvis CT (CAP CT) was 72%, specificity 97%, false positive rate 3%, false negative rate 28% and diagnostic accuracy 87%. Eleven patients were not diagnosed of spinal injury with CAP CT and C-spine lateral view, but all of them were diagnosed of stable fractures. Conclusions: C-spine CT scan be actively considered in the initial examination process. When CAP CT scan is performed in major blunt trauma patients with impaired consciousness, CTL-spine CT scan or simple spinal radiography has no significant effect on the prognosis of the patient and can be performed if necessary.

• 한국가축번식학회지
• /
• 제13권3호
• /
• pp.149-156
• /
• 1989

These experiment was carried out to improve the precision of early pregnancy diagnosis in dairy cattle. Changes in progesterone concentration of milk were measured by Enzyme Immunoassay(EIA) in 73 cows up to 21 days after insemination. The average concentraton of progesterone in milk was 1.9ng/ml at eatrus ; it increased to 17.8ng/ml on day 14, and thereafter it declined to 4.3ng/ml on day 21 in nonpregnant cows. Whereas in pregnant animals, it was maintained and elevated further to 22.2ng/ml on day 21. The accuracy of the pregnancy diagnosis for animals classified as positive (pregnant ; over 10ng/ml and decreasing rate<1.5) and negative (non-pregnant ; under 7ng/ml and decreasing rate>1.5) were 95% and 100% respectively. The samples ranging between 7ng/ml and 10ng/ml were classified as positive (decreasing rate<1.5) and negative(>1.5), which accuracy was 54.5% and 100% respectively. However this range appears to be of the most interest for the veterinary practitioner since cows in proestrus or early interestrus tend to have milk progesterone levels within this value. Causes for the insufficient precision of false pregnancy diagnosis are discussed.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권1호
• /
• pp.237-241
• /
• 2012

Objective: Screening for colorectal cancer using guaiac-based fecal occult blood tests (gFOBT) is well established in Western populations, but is hampered by poor patient compliance due to the imposed dietary restrictions. Fecal immunochemical tests (FIT) do not require dietary restriction, but are more expensive than gFOBT and therefore restrict its use in developing countries in Asia. However, Asian diets being low in meat content may not require diet restriction for gFOBT to achieve equivalent results. The objective of this study was to evaluate and compare the validity and suitability of gFOBT and FIT or a combination of the two in screening for colorectal neoplasias without prior dietary restriction in an Asian population. Methods: Patients referred to the Endoscopic Unit for colonoscopy were recruited for the study. Stool samples were collected prior to bowel preparation, and tested for occult blood with both gFOBT and FIT. Dietary restriction was not imposed. To assess the validity of either tests or in combination to detect a neoplasm or cancer in the colon, their false positive rates, their sensitivity (true positive rate) and the specificity (true negative rate) were analyzed and compared. Results: One hundred and three patients were analysed. The sensitivity for picking up any neoplasia was 53% for FIT, 40% for gFOBT and 23.3% for the combination. The sensitivities for picking up only carcinoma were 77.8%, 66.7% and 55.5%, respectively. The specificity for excluding any neoplasia was 91.7% for FIT, 74% for gFOBT and 94.5% for a combination, whereas for excluding only carcinomas they were 84%, 73.4% and 93.6%. Of the 69 with normal colonoscopic findings, FOBT was positive in 4.3%, 23.2 %and 2.9% for FIT, gFOBT, or combination of tests respectively. Conclusion: FIT is the recommended method if we are to dispense with dietary restriction in our patients because of its relatively low-false positivity and better sensitivity and specificity rates.

• 대한교통학회지
• /
• 제31권4호
• /
• pp.85-94
• /
• 2013

Continuous Risk Profile(CRP)은 고속도로의 사고취약구간을 선정하는 방법론 중에서 정확성과 효율성이 뛰어난 것으로 알려져 있다. 그러나 전통적인 CRP는 데이터베이스 구축을 위한 대규모 투자를 필요로 하는 안전성능함수를 이용한다. 본 연구는 안전성능함수 대신 동질 그룹들의 평균사고건수를 규모조정계수로 이용하는 CRP를 제안하는 것을 목적으로 한다. 고속도로 구간들을 동질 그룹으로 분류하기 위하여 각 구간의 AADT와 차로 수 자료를 기반으로 하는 계층적 군집분석이 수행된다. 제안된 모형은 캘리포니아의 I-880 자료를 이용하여 다른 여러 가지 사고취약구간 선정방법들과 비교된다. 분석 결과에 따르면, 제안된 모형은 false negative를 발생시키지 않으며 false positive rate를 감소시킨다. 본 연구에서 개발된 방법론은 추가적인 복잡한 데이터베이스 없이 고속도로 사고취약구간을 선정하는 데에 활용될 수 있으며, 또한 고속도로 안전관리시스템을 개선하는 데에 기여할 수 있다.

• 한국산학기술학회논문지
• /
• 제10권4호
• /
• pp.811-817
• /
• 2009

IT 시스템 기반의 네트워크 환경의 급속한 발전은 지속적인 연구방향의 중요한 이슈의 결과이다. 침입시도 탐지는 관심분야의 하나인 것이다. 최근에 다양한 기술을 기반으로 하는 침입시도탐지들이 제안되고 있으나 이러한 기술은 여러 형태의 침입시도의 패턴 중에 한가지 형태 및 시스템에 적용이 가능한 것이다. 또한 새로운 형태 침입시도를 탐지하지 못하고 있다. 그러므로 새로운 형태를 인식하는 침입탐지 관련 기술이 요구되어 지고 있다. 본 연구에서는 퍼지인식도와 비정상 트래픽 분석을 이용한 네트워크 기반의 침입탐지기법(NePID)을 제안한다. 이 제안은 패킷 분석을 통하여 서비스거부공격과 유사한 침입시도를 탐지하는 것이다. 서비스거부공격은 침입시도의 형태를 나타내며 대표적인 공격으로는 syn flooding 공격이 있다 제안한 기법은 syn flooding을 탐지하기 위하여 패킷정보를 수집 및 분석한다. 또한 피지인식도와 비정상 트래픽 분석을 적용하여 판단모듈의 분석 결과를 토대로 기존의 서비스 거부 공격의 탐지 툴과의 비교분석을 하였으며 실험데이터로는 MIT Lincoln 연구실의 IDS 평가데이터 (KDD'99)를 이용하였다. 시뮬레이션 결과 최대평균 positive rate는 97.094% 탐지율과 negative rate는 2.936%을 얻었으며 이 결과치는 KDD'99의 우승자인 Bernard의 결과치와 유사한 수준의 값을 나타내었다.