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Clinical Features of Dermatomyositis/Polymyositis(DM/PM) with Lung Involvement (폐를 침범한 피부근염/다발성근염의 임상적 양상)

  • Park, Gun-Min;Choi, Chang-Min;Um, Sang-Won;Hwang, Yong-Il;Yim, Jae-Joon;Lee, Jae-Ho;Yoo, Chul-Gyu;Lee, Choon-Taek;Chung, Hee-Soon;Song, Young-Wook;Kim, Young-Whan;Han, Sung-Koo;Shim, Young-Soo
    • Tuberculosis and Respiratory Diseases
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    • v.51 no.4
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    • pp.354-363
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    • 2001
  • Background : Although lung involvement has been reported in 5 to 46% of dermatomyositis/polymyositis(DM/PM) patients, reports of the condition in Korea are rare. This study evaluated the clinical features of lung involvement in DM/PM patients. Methods : The medical records, laboratory results and radiologic findings of 79 DM/pM patients, who attended the Seoul National University Hospital (SNUH) between 1989 and 1999, were reviewed retrospectively. Results : A total 79 patients of whom 24 patients(33%) showed lung involvement, were enrolled in this study. More patients with lung involvement were female(F:M=11:1), and older compared with those without lung involvement. Patients with lung involvement presented with dyspnea(79%), coughing(67%), an elevated ESR, and CK/LD. Anti-Jo 1 antibody test was positive in 30%, which is significantly higher in patients with lung involvement. A simple chest X-ray of the patients with lung involvement exhibited reticular opacity(50%), reticulonodular opacity(30%), patchy opacity(29%), nodular opacity(13%) and linear opacity(4%). HRCT(n=24) showed ground glass opacity(75%), linear or septal thickening(50%), patchy consolidation(42%), honey-combing(33%) and nodular opacity(17%). The pulmonary function test showed a restrictive ventilatory pattern(77%) and a lower diffusing capacity(62%). The patients were followed up during a mean duration of $30{\pm}28$ months. They were treated with steroid only(50%) or a combination of steroids and cytotoxic agents(46%). Muscle symptoms were improved in 89% with treatment, but an improvement in the respiratory symptoms or in the pulmonary function test was rare. Patients with lung involvement had a higher mortality rate(21%) than those without lung involvement(10%) during the follow-up periods. Conclusion : DM/PM patients with lung involvement were mostly female, older and had a higher positive rate Anti-Jo 1 antibodies, but there was no significant difference in prognosis.

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A Study on LRFD Reliability Based Design Criteria of RC Flexural Members (R.C. 휨부재(部材)의 L.R.F.D. 신뢰성(信賴性) 설계기준(設計基準)에 관한 연구(研究))

  • Cho, Hyo Nam
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.1 no.1
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    • pp.21-32
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    • 1981
  • Recent trends in design standards development in some European countries and U.S.A. have encouraged the use of probabilistic limit sate design concepts. Reliability based design criteria such as LSD, LRFD, PBLSD, adopted in those advanced countries have the potentials that they afford for symplifying the design process and placing it on a consistent reliability bases for various construction materials. A reliability based design criteria for RC flexural members are proposed in this study. Lind-Hasofer's invariant second-moment reliability theory is used in the derivation of an algorithmic reliability analysis method as well as an iterative determination of load and resistance factors. In addition, Cornell's Mean First-Order Second Moment Method is employed as a practical tool for the approximate reliability analysis and the derivation of design criteria. Uncertainty measures for flexural resistance and load effects are based on the Ellingwood's approach for the evaluation of uncertainties of loads and resistances. The implied relative safety levels of RC flexural members designed by the strength design provisions of the current standard code were evaluated using the second moment reliability analysis method proposed in this study. And then, resistance and load factors corresponding to the target reliability index(${\beta}=4$) which is considered to be appropriate level of reliability considering our practices are calculated by using the proposed methods. These reliability based factors were compared to those specified by our current ultimate strength design provisions. It was found that the reliability levels of flexural members designed by current code are not appropriate, and the code specified resistance and load factors were considerably different from the reliability based resistance and load factors proposed in this study.

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