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971.
Balloon occlusion hepatic venography using carbon dioxide (CO2) is proposed as a safer yet simpler alternative to wedged catheter techniques that have caused hepatic lacerations during the transjugular intrahepatic portosystemic shunt (TIPS) procedure. The image quality of CO2 wedged catheter and balloon occlusion venograms was comparable in our small series, with no venographic-related complications occurring in the balloon occlusion group.  相似文献   
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973.
974.
BACKGROUND: There have been several investigations suggesting an involvement of activated neutrophils in the development of grain dust (GD)-induced occupational asthma. Interleukin-8 in the sputa from GD-induced asthmatic patients increased significantly after the exposure to GD. OBJECTIVE: To confirm IL-8 production from bronchial epithelial cells when exposed to GD, and to evaluate the role of IL-8 on neutrophil recruitment. MATERIALS AND METHOD: We cultured Beas-2B, a bronchial epithelial cell line. To observe GD-induced responses, four different concentrations ranging from 1 to 200 microg/mL of GD were incubated for 24 hours and compared with those without incubation of GD. To evaluate the effect of pro-inflammatory cytokines on IL-8 production and neutrophil chemotaxis, epithelial cells were incubated with peripheral blood mononuclear cell (PBMC) culture supernatant derived from subjects with GD-induced asthma exposed to 10 microg/mL of GD, and then compared with those without addition of PBMC supernatant. The level of released IL-8 in the supernatant was measured by enzyme-linked immunosorbent assay. Neutrophil chemotactic activity of the culture supernatant was determined by modified Boyden chamber method. RESULTS: Interleukin-8 production and neutrophil chemotactic activity from bronchial epithelial cells significantly increased with additions of GD in a dose-dependent manner (P < .05, respectively), and were significantly augmented with additions of PBMC supernatant (P < .05, respectively) at each concentration. Close correlation was noted between neutrophil chemotactic activity and IL-8 level (r = 0.87, P < .05). Compared with the untreated sample, pre-treatment of anti-IL-8 antibody induced a significant suppression (up to 67.2%) of neutrophil chemotactic activity in a dose-dependent manner. CONCLUSION: These results suggest that IL-8 produced from bronchial epithelial cells may be a major cytokine, which induces neutrophil migration into the airways when exposed to GD.  相似文献   
975.
BackgroundThere are limited data regarding the extraintestinal manifestations (EIMs) associated with pediatric inflammatory bowel disease (IBD) in Korea. We aimed to investigate the clinical features and factors associated with the development of EIMs in Korean children and adolescents with IBD.MethodsThis multicenter, retrospective study was conducted from 2010 to 2017. Baseline clinicodemographic, laboratory findings, disease activity, disease phenotypes, and EIMs were investigated.ResultsA total of 172 patients were included. One-hundred thirty-seven (79.7%) had Crohn''s disease (CD), and 35 (20.3%) had ulcerative colitis (UC). EIMs occurred in 42 patients (24.4%). EIMs developed in 34/137 diagnosed with CD (24.8%), and in 8/35 diagnosed with UC (22.9%), during a median follow-up duration of 3.2 (interquartile range, 1.9–5.4) years for CD and 3.0 (1.0–4.0) years for UC, respectively. Arthritis/arthralgia was most commonly observed (n = 15, 35.7%), followed by stomatitis/oral ulcer (n = 10, 23.8%), hepatitis (n = 5, 11.9%), nephritis (n = 4, 9.5%), pancreatitis (n = 2, 4.8%), erythema nodosum (n = 2, 4.8%), pyoderma gangrenosum (n = 1, 2.4%), primary sclerosing cholangitis (n = 1, 2.4%), uveitis (n = 1, 2.4%), and ankylosing spondylitis (n = 1, 2.4%). A significant difference in disease severity based on the Paris classification (P = 0.011) and ESR at diagnosis (P = 0.043) was observed between the EIM positive and negative group in patients with UC. According to logistic regression analyses, S1 disease severity based on the Paris classification was the only factor that was significantly associated with the development of EIMs (odds ratio, 16.57; 95% confidence interval, 2.18–287.39; P = 0.017).ConclusionSevere disease activity based on the Paris classification in pediatric patients with UC was significantly associated with EIM development. As disease severity in the Paris classification is a dynamic parameter, treatment should be focused on disease control to minimize the occurrence of EIMs in Korean children and adolescents with UC.  相似文献   
976.
BackgroundIn Korea, the first community outbreak of coronavirus disease 2019 (COVID-19) occurred in Daegu on February 18, 2020. This study was performed to investigate the prevalence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in healthcare workers (HCWs) at 6 major hospitals in Daegu.MethodsBlood specimens of 2,935 HCWs at 6 major hospitals in Daegu from January 2021 to February 2021 were collected. Every specimen was tested for antibody against SARS-CoV-2 using both Elecsys Anti-SARS-CoV-2 electrochemiluminescence immunoassay (Roche Diagnostics, Rotkreuz, Switzerland) and R-FIND COVID-19 IgG/M/A enzyme-linked immunosorbent assay kit (SG medical Inc., Seoul, Korea) as screening tests. If 1 or more of these screening test results was positive, 2 additional antibody tests were performed using Abbott Anti-SARS-CoV-2 IgG assay (Abbott, Abbott Park, IL, USA) and cPass SARS-CoV-2 Neutralization Antibody Detection Kit (GenScript USA Inc., Piscataway, NJ, USA). If 2 or more of the total 4 test results were positive, it was determined as positive for the antibody against SARS-CoV-2.ResultsAccording to the criteria of SARS-CoV-2 antibody positivity determination, 12 subjects were determined as positive. The overall positive rate of the SARS-CoV-2 antibody was 0.41% (12/2,935). Of the 12 subjects determined as positive, 7 were diagnosed with COVID-19, and the remaining 5 were nondiagnosed cases of COVID-19.ConclusionIn early 2021, the overall seroprevalence of SARS-CoV-2 antibody among HCW located in Daegu was 0.41%, and 0.17% excluding COVID-19 confirmed subjects. These results were not particularly high compared with the general public and were much lower than HCWs in other countries.  相似文献   
977.
In order to investigate the electrorheological (ER) behavior of monodisperse colloidal suspensions, polyaniline (PANi) composite particles were synthesized by chemically oxidative polymerization of aniline in the presence of macroporous polymer particles. Particle characterization was carried out by FT‐IR spectroscopy, conductometry and scanning electron microscopy. ER properties of PANi composite suspensions under various electric fields were then investigated and consequently found to be dependent on the particle compositions and the applied electric field strength.  相似文献   
978.
Laser photochemotherapy of malignancies may become an effective palliative treatment for advanced had and neck cancer using light-sensitive, chemotherapeutic drugs activated in tumors via interstitial laser fiberoptics. Previously, it was reported that cultured human P3 squamous cells incubated 2 hours with daunomycin (Dn) exhibited tenfold enhanced cytotoxicity after exposure to argon laser light at 514 nm. This short-term uptake leads to drug localization in cytoplasmic and membrane sites prior to nuclear accumulation and daunomycin topoisomerase inhibition. In the current study phototoxicity of Dn-sensitized human cancer cells was tested using broad-spectrum white light compared to monochromatic green-wavelength light. Drug uptake and laser energy levels were optimized for maximum synergy. To test light-enhanced chemotherapy in vitro, the kinetics of cell uptake and toxicity of daunomycin was measured at 1, 2, and 5 μg/ml in three human tumor cell lines: P3 squamous-cell carcinoma, M26 melanoma, and TE671 fibrosarcoma. After 2 hr Dn uptake, all cell lines were tested for phototherapy response by exposure to 300- to 900-nm visible light from a xenon lamp or monochromatic 532-nm green light from a KTP laser. When the KTP laser output was varied from 0 to 120 Joules in Dn-sensitized tumor cells, a linear phototherapy response was seen with energy as low as 12 J inducing drug phototoxicity. These results provide evidence that daunomycin cytotoxicity is enhanced when exposed to 532-nm laser illumination in the three tumor types tested and confirm that the response is related to both energy level and drug dose. Lasers Surg. Med. 23:33–39, 1998. © 1998 Wiley-Liss, Inc.  相似文献   
979.
The purpose of the present study was to provide detailed information of the morphological and radiological characteristics of the posterolateral structures of the knee. Muscles and ligaments of the posterolateral part of the knee were studied by dissections of 50 adult cadaver knees and by Magnetic Resonance Imaging (MRI) before and after dissections for comparisons. Diverse morphological characteristics of the arcuate ligament were found. The fabellofibular ligament was present in 42.1% of the knees dissected, whereas the popliteofibular ligament was found in 37.5%. A ligamentous structure, which could be called the posterior tibial ligament, was found in 31.6% of the cases that originated from the lateral part of the capsule proximally and inserted distally on the mid portion of the proximal tibia. By comparing the cross sections and the dissections of the cadaver knees, the popliteus muscle, the arcuate ligament, the fibular collateral ligament, the popliteofibular ligament, and the fabellofibular ligament could be identified in MRI. Comprehensive understanding of the posterolateral anatomy of the knee and improved identification of the structures in MRI will help clinicians to make a more accurate and noninvasive diagnosis of posterolateral instability. Clin. Anat. 10:397–404, 1997. © 1997 Wiley-Liss, Inc.  相似文献   
980.
BackgroundThe COVID-19 outbreak had a severe impact on health care workers'' psychological health. It is important to establish a process for psychological assessment and intervention for health care workers during epidemics.ObjectiveWe investigated risk factors associated with psychological impacts for each health care worker group, to help optimize psychological interventions for health care workers in countries affected by the COVID-19 pandemic.MethodsRespondents (n=1787) from 2 hospitals in Korea completed a web-based survey during the period from April 14 to 30, 2020. The web-based survey collected demographic information, psychiatric history, and responses to the 9-item Stress and Anxiety to Viral Epidemics (SAVE-9), 9-item Patient Health Questionnaire (PHQ-9), and 7-item Generalized Anxiety Disorder-7 (GAD-7) scales. We performed logistic regression to assess contributing factors as predictor variables, using health care workers’ depression as outcome variables.ResultsAmong 1783 health care workers, nursing professionals had significantly higher levels of depression (PHQ-9 score: meannurse 5.5, SD 4.6; meanother 3.8, SD 4.2; P<.001), general anxiety (GAD-7 score: meannurse 4.0, SD 4.1; meanother 2.7, SD 3.6; P<.001), and virus-related anxiety symptoms (SAVE-9 score: meannurse 21.6, SD 5.9; meanother 18.6, SD 6.3; P<.001). Among nursing professionals, single workers reported more severe depressive symptoms than married workers (PHQ-9 score ≥10; meannurse 20.3%; meanother 14.1%; P=.02), and junior (<40 years) workers reported more anxiety about the viral epidemic (SAVE-9 anxiety score; meannurse 15.6, SD 4.1; meanother 14.7, SD 4.4; P=.002). Logistic regression revealed that hospital (adjusted odds ratio [OR] 1.45, 95% CI 1.06-1.99), nursing professionals (adjusted OR 1.37, 95% CI 1.02-1.98), single workers (adjusted OR 1.51, 95% CI 1.05-2.16), higher stress and anxiety to the viral infection (high SAVE-9 score, adjusted OR 1.20, 95% CI 1.17-1.24), and past psychiatric history (adjusted OR 3.26, 95% CI 2.15-4.96) were positively associated with depression.ConclusionsPsychological support and interventions should be considered for health care workers, especially nursing professionals, those who are single, and those with high SAVE-9 scores.  相似文献   
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