• 제목/요약/키워드: Low Perfusion

검색결과 154건 처리시간 0.024초

SPECT 심근영상의 영상분할을 이용한 3차원 재구성 (3D Reconstruction Using Segmentation of Myocardial SPECT)

  • 정재은;이준행;최석윤;이상복
    • 한국산학기술학회논문지
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    • 제11권6호
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    • pp.2240-2245
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    • 2010
  • 심근영상의 SPECT(Single Photon Emission Computed tomography)검사는 감마선을 방출하는 방사성의약품을 환자에게 정맥주사한 후 이 의약품이 심장에 고루 퍼지면 관심부위를 촬영하여 질병으로 인한 변화를 컴퓨터를 이용하여 진단하는 검사법이다. 기능적인 정보를 담고 있는 심근관류 영상은 비침습적인 심근질환 검사에 유용한 방법이지만, 물리적 인자들에 의해 잡음과 낮은 해상도는 판도하는데 어려움을 주게 된다. 본 논문은 심근영상을 레벨 셋 알고리즘을 이용하여 영상을 분할하고 분할된 영역을 3차원으로 구현하여 판독에 도움을 주는 방안을 제안하였다. 판독의 어려움을 해결하기 위하여 레벨 셋을 이용하여 관심부위인 좌심실 영역을 분할하였고 분할된 영역을 3차원영상으로 모델링 하였다.

Antitumor Activity of Chloroquine in Combination with Cisplatin in Human Gastric Cancer Xenografts

  • Zhang, Hui-Qing;Fang, Nian;Liu, Xiao-Mei;Xiong, Shu-Ping;Liao, Yu-Qian;Jin, Wen-Jian;Song, Rong-Feng;Wan, Yi-Ye
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권9호
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    • pp.3907-3912
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    • 2015
  • Purpose: To investigate the antitumor activity and mechanism of chloroquine (CQ) in combination with cisplatin (DDP) in nude mice xenografted with gastric cancer SGC7901 cells. Materials and Methods: 35 cases of gastric cancer patients with malignant ascites were enrolled and intraperitoneal cisplatin injection was performed. Ascites were collected before and 5 days after perfusion for assessment of autophagy levels in cancer cells. In addition, 24 tumor-bearing mice were randomly divided into control, DDP, CQ and CQ + DDP groups. Results: In 54.3% (19/35) of patients the treatment was therapeutically effective (OR), 5 days after peritoneal chemotherapy, 13 patients had the decreased ascites Beclin-1 mRNA levels. In 16 patients who had NR, only 2 cases had decreased Beclin-1 (P=0.001). Compared with the control group, the xenograft growth in nude mice in the DDP group was low, and the inhibition rate was 47.6%. In combination with chloroquine, the inhibition rate increased to 84.7% (P<0.01). The LC3-II/I ratio, and Beclin1 and MDR1/P-gp expression were decreased, while caspase 3 protein levels increased (P<0.05). Conclusions: Antitumor ability of cisplatin was associated with autophagy activity and chloroquine can enhance chemosensitivity to cisplatin in gastric cancer xenografts nude mice.

유경횡복직근피판을 이용한 유방복원술시 폐색전증의 발병률과 위험인자 (Incidence and Risk Factors of Pulmonary Thromboembolism in Pedicled TRAM Breast Reconstruction)

  • 이상혁;이택종;엄진섭;손병호;안세현;이상도
    • Archives of Plastic Surgery
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    • 제33권2호
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    • pp.193-197
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    • 2006
  • Pulmonary thromboembolism is often clinically silent and difficult to diagnose, and can be fatal to patients with belated treatment. This complication is seen in patients who underwent TRAM breast reconstruction. Multiple factors are involved in this disease such as the presence of malignancy itself, major surgery and therapy-related interventions. TRAM surgery is a lengthy procedure involving mastectomy, flap surgery and abdominoplasty. The purpose of this study is to evaluate the incidence and the correlation between presurgical risk factors(BMI and age) of symptomatic pulmonary thromboembolism after TRAM surgery and the incidence. From July 2001 to March 2005 a total of 384 pedicled TRAM reconstruction of breast was performed in 382 patients at Asan Medical Center. The average of Body mass index was $21.9kg/m^2$ and mean age of the patients was 37.9 years old. We diagnosed symptomatic pulmonary thromboembolism using ventilation/perfusion lung scan and pulmonary embolism computed tomography. Incidence of in-hospital symptomatic pulmonary thromboembolism was 1.3%. BMI and age showed no significant statistical relationship to pulmonary thromboembolism. But the incidence of symptomatic pulmonary thromboembolism in obese patients (BMI > 25) was 3.75%. According to the guideline of the 7th American College of Chest Physicians Consensus Conference on Antithrombotic and Thrombolytic Therapy, the incidence of 3.75% was classified as high risk group. The prevention of pulmonary thromboembolism should be considered in cases of obese patients with low molecular weight heparin(BMI > 25).

한 대학병원에서 급성 폐색전증으로 진단된 환자들의 임상적 특성 및 예후 (Acute Pulmonary Embolism: Clinical Characteristics and Outcomes in a University Teaching Hospital)

  • 채진녕;최원일;박지혜;노병학;김재범
    • Tuberculosis and Respiratory Diseases
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    • 제68권3호
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    • pp.140-145
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    • 2010
  • Background: Pulmonary embolism (PE) is a common clinical problem in the West that is associated with substantial morbidity and mortality. The diagnostic modality has been changed since 2001. This study retrospectively reviewed the PE mortality with the aim of identifying the risk factors associated with mortality since the multidetector computed tomography (MDCT) was introduced. Methods: We analyzed 105 patients with acute PE proven by multidetector CT or ventilation perfusion scan. The primary outcome measure was the all-cause mortality at 3 months. The prognostic effect of the baseline factors on survival was assessed by multivariate analysis. Results: The main risk factors were prolonged immobilization, stroke, cancer and obesity. Forty nine percent of patients had 3 or more risk factors. The overall mortality at 3 months was 18.1%. Multivariate analysis revealed low diastolic blood pressure and the existence of cancer to be independent factors significantly associated with mortality. Forty two PE patients were examined for the coagulation inhibitors. Four of these patients had a protein C deficiency (9.5%), and 11 had a protein S deficiency (26%). Conclusion: PE is an important clinical problem with a high mortality rate. Close monitoring may be necessary in patients with the risk factors.

소아 상부요로감염의 진단을 위한 출력 도풀러 초음파조영술 (Power Doppler Sonography for the Upper Urinary Tract Infection in Children)

  • 최정연;조재호;박용훈
    • Journal of Yeungnam Medical Science
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    • 제24권2호
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    • pp.179-185
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    • 2007
  • 결론적으로 출력 도플러 신초음파는 급성신우신염의 병변을 찾는데에 특이도나 민감도가 그리 높지 않았으나 하부요로감염과 급성신우신염을 감별하는데에 어느 정도 유용하였으며, 특히 DMSA 스캔을 같이 실시하는 경우에는 신손상을 찾는데 더 도움이 될 수 있었다. 소아들의 상부요로감염의 진단을 위하여 출력 도플러 신초음파가 DMSA 스캔을 대체하는 영상검사로서는 한계가 있어 향후 보다 많은 시술로 진단을 위한 검사의 질을 높이는 방법을 찾아보아야 할 것이다.

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저혈청 배지에서 인간 전골수세포(HL-60)를 이용한 tPA 생산과 세포사멸기작에 관한 연구 (The Production of Tissue Type-Plasminigen Activator and Mechanism of Cell Death from Human Promyelocytes(HL-60) in Low Serum Containing Medium)

  • 김현구;성기돈;김태호;안주희;함문선;박진서;이현용
    • 한국미생물·생명공학회지
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    • 제24권1호
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    • pp.126-131
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    • 1996
  • HL-60 was cultivated to produce tPA (tissue-type plasminogen activator) and study the mechanism of cell death. Maximum cell density and tPA production were obtained as $5.27{\times}10^6$ cells/ml and 324ng/ml, respectively under perfusion cultivation. tPA production was enhanced to 420ng/ml in adding 160nM of phorbol ester. The cells were gradually differentiated to granulocytes rather than proliferation. By Fluorescent microscope, apoptosis was prevailed except the death phase and in high agitation speed, but necrosis was prevailed in thawed cells and during the latter periods of the cultivation. It was also proved that tPA was most produced in apoptosis. To obtain higher tPA productivity, the cells must be maintained in apoptosis, not necrosis phase when the cells were dying.

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개심술을 시행하는 환자에서 경식도 심초음파의 이용 (The Usefulness of Transesophageal Echocardiography During Heart Surgery)

  • 조규도;김치경
    • Journal of Chest Surgery
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    • 제30권12호
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    • pp.1205-1213
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    • 1997
  • 가톨릭대학교 의과대학 부속 성바오로 병원에서 1996년 1월부터 7월까지 개심술시 경식도심초음파를 이용하여 수술 중 관찰한 61명의 증례를 분석하여 다음과 같은 결과를 얻었다. 61명의 환자 중 질병 분류는 심장 판막 질환 25명, 관상동맥 질환 22명, 선천성 심질환 13명, 심장 판막 질환과 관상동맥 질환이 병발한 경우가 1명 이었다. 1. 경식도심초음파를 이용하여 선천성 심질환 1예(심실중격결손증 재수술)와 대동맥 판막 치환술을 시행한 환자 1예에서 일차 심정지에 의한 수술 후 잔존 단락과 판막 주위 누출이 확인되어 재심정지를 유도하여 수술을 완료하였다 2. 공기색전증의 발생을 전 예에서 방지할 수 있었다. 3. 경식도심초음파로 측정한 심박출량과 온도희석법으로 측정한 심박출량은 통계학적으로 의미있는 상관관계를 보여 경식도 초음파를 이용한 심박출량 감시가 의미 있음을 시사하였다(Linear regression analysis, p<0.001). 4. 관상동맥우회로술을 시행한 23명의 환자에서 수술 중 경식도 초음파도상 이상 벽운동을 보이는 분절의 도부타민 투여 전후와 관상동맥우회로술 후의 반응을 비교 관찰하였다. 저 용량 도부타민 검사는 통계적으 \ulcorner유의하였다(민감도 76%, 특이도 94.7%, 양성 예측율 95%, 음성 예측율 75%).

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두경부 악성종양 환자에서 유리조직이식 후 시행한 혈류장애 구제술 (Emergent Exploration after Free Tissue Transfer in Head and Neck Cancer)

  • 장용준;정철훈;이종욱;조우성;김진환;노영수
    • Archives of Reconstructive Microsurgery
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    • 제17권1호
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    • pp.19-27
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    • 2008
  • Purpose: Microvascular reconstructive surgery has become an integral part of the treatment of head and neck cancer patients. This review of 121 free flaps for head and neck cancer patients performed over the last 11 years was done to evaluate circulatory crisis, salvage, and secondary reconstruction and to investigate which factors may contribute to these rates. Method: Nine emergent explorations among 121 head and neck reconstruction with free flaps were reviewed to analyze detection of vascular crisis, the time interval from detection of circulatory crisis to exploration, operation procedures and results, and secondary reconstructions. Emergent exploration was done with our protocol. Result: Nine free flaps exhibited signs of vascular problems between 1 day and 6 days postoperatively. The emergent exploration rate of this series was 7.4% (9/121). The salvage rate was 55.6% (5/9), giving an overall flap viability of 96.7% (117/121). In our study, preoperative radiation therapy, positive smoking history, alcohol consumption history, combined disease such as diabetes mellitus and hypertension, recipient vessels and types of vascular anastomosis were not related to the causes of circulatory crisis. The mean time interval between the onset of clinical recognition of impaired flap perfusion and re-exploration of the salvaged 5 flaps was 3.2 hours, that of failed 4 flaps was 11.25 hours. Conclusion: Despite high overall success rate, relatively low salvage rate may be attributed to late detection of circulatory crisis and in long time interval between detection and exploration. We conclude that early detection of circulatory crisis and expeditious re-exploration are a matter of great importance for the success of salvage operation.

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Utility of Toe-brachial Index for Diagnosis of Peripheral Artery Disease

  • Park, Seong-Chul;Choi, Chang-Yong;Ha, Young-In;Yang, Hyung-Eun
    • Archives of Plastic Surgery
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    • 제39권3호
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    • pp.227-231
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    • 2012
  • Background : The ankle brachial pressure index (ABI) is a simple, useful method for diagnosing peripheral artery disease (PAD). Although the ABI is an objective diagnostic method, it has limited reliability in certain scenarios. The aim of the present study was to determine the accuracy and reliability of the toe brachial index (TBI) as a diagnostic tool for detecting stenosis in PAD, associated with normal or low ABI values. Methods : ABI and TBI values were measured in 15 patients with diabetic gangrene who were suspected of having lower extremity arterial insufficiency. The ABI and TBI values were measured using a device that allowed the simultaneous measurement of systolic blood pressure in the upper and lower extremities. In addition, the ABI and TBI values were compared pre- and post-angiography. Results : Patients with an ABI of 0.9-1.3 showed almost no difference between the 2 measurements. The patients with TBI >0.6 had no arterial insufficiency. The patients with TBI <0.6 required vascular intervention with ballooning. After the angiography, the gangrenous wounds decreased in size more rapidly than they did prior to the intervention. Conclusions : Our findings suggest that TBI is the method of choice for evaluating lower limb perfusion disorders. This result requires further studies of TBI in a larger number of patients. Future long-term studies should therefore evaluate the utility of TBI as a means of screening for PAD and the present findings should be regarded as preliminary outcomes.

Effect of vitamin C on hepatic drug metabolism in hypoxia/reoxygenation

  • Lee, Hae-;Jung, Ju-Yeon;Han, Suck-Hee;Cho, Tai-Soon;Lee, Sun-Mee
    • 한국응용약물학회:학술대회논문집
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    • 한국응용약물학회 1998년도 Proceedings of UNESCO-internetwork Cooperative Regional Seminar and Workshop on Bioassay Guided Isolation of Bioactive Substances from Natural Products and Microbial Products
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    • pp.191-191
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    • 1998
  • It has been hypothesized that formation of oxygen-derived free radicals may play an important part in ischemically induced tissue injury. In this study, the effects of vitamin C treatment on hepatic reperfusion model were investigated. Livers isolated from 18 hrs fasted rats were subjected to low flow hypoxia (1 $m\ell$/g liver/min, for 45min) followed by reoxygenation (for 30min). The perfusion medium used was Krebs-Henseleit bicarbonate buffer (KHBB, pH 7.4) and vitamin C (0.25, 0.5, 1.0 and 2.0 mM) was added to perfusate. 7-Ethoxycoumarin was used as substrate of phase and metbolism. After hypoxia oxygen consumption significantly dropped but vitamin C 0.25, 0.5 and 1.0 mM treatments restored oxygen consumption to the level of control group. LDH and lipid peroxidation were not changed in all experimental groups. Oxidation, phase metabolism, significantly decreased following hypoxia but improved during reoxygenation. Vitamin C 0.25 mM treatment significantly improved the oxidation of 7-ethoxycoumarin during hypoxia and reoxygenation, but the oxidation significantly decreased by vitamin C 2.0 mM treatment. Similarly, sulfate conjugation decreased in hypoxic group, but this decrease was inhibited by vitamin C 0.25, 0.5 and 1.0 mM treatments. Our findings suggest that hypoxia/reoxygenation diminishes hepatic drug metabolizing function, vitamin C at concentration of 0.25-1.0 mM ameliorates but at higher concentration aggravates these hypoxia/reoxygenation-induced changes.

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