• Title/Summary/Keyword: observed survival

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Comparative study on longevity of Anopheles sinensis in malarious and non-malarious areas in Korea

  • Ree, Han-Il;Hwang, Ui-Wook
    • Parasites, Hosts and Diseases
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    • v.38 no.4
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    • pp.263-266
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    • 2000
  • An outbreak of vivax malaria has been occurring in northern part of Kyonggi-do and north-western part of Kangwon-do, where are located near the demilitarized Zone, since 1993. For understanding of epidemiological features of malaria, the probability of daily survival of Anopheles sinensis, the vector species of malaria was compared in malarious and non-malarious areas in July-August, 2000. Total 915 females collected at three locations in malarious areas were dissected for ovaries, and 64.6% of the parous rate was found. Total 758 females collected at three locations in non-malarious areas were dissected, and 57.8% of the parous rate was observed. It was estimated from the parous rates that the probability of daily survival of An. sinensis females was 0.864 in malarious areas and 0.850 in non-malarious areas, which was not significantly different.

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ELECTRON MICROSCOPIC STUDY ON TENSION ZONES OF RAT MOLAR PERIODONTIUM INCIDENT TO ORTHODONTIC TOOTH MOVEMENT (백서 구치의 교정적 치아이동중 장력측 치주조직의 반응에 관한 전자현미경적 연구)

  • Lee, Jung Hun;Lee, Ki Soo
    • The korean journal of orthodontics
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    • v.17 no.2
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    • pp.223-248
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    • 1987
  • The early tissue reactions in the periodontal tissues of the tension zones following the application of force (30gm) to the maxillary first molar teeth of the albino rats were studied by the light microscopy and electron microscopy The increase of periodontal fibroblasts was evident, particularly in 1 day survival period. Osteoblast differentiation and new bone formation on the alveolar bone surface were occurred from 1 day survival period. Mononuclear phagocytes occurred consistently and in relatively high number adjacent to and at some distance from blood vessel Extensive breakdown of collagen fibers was observed. The increase of the phagocytosis of collagen by the active fibroblasts was evident Also, collagen fibrils were sparse or lost near the macrophage.

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Effects of low temperature and salicylic acid on chilling tolerance in cucumber seedlings

  • Jung, Sang-Duck;Jung, You-Jin;Kim, Tae-Yun;Hong, Jung-Hee
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2002.05b
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    • pp.468-471
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    • 2002
  • The present study was undertaken to Investigate the effects of low temperature and salicylic acid (SA) on chilling tolerance In acclimated and nonacclimated cucumber seedlings. Acclimation significantly affected survival and shoot dry weights. Injuries of acclimated seedlings at the third leaf stage were on the average smaller by half than those of the nonacclimated ones. Chilling caused a large increase in free proline levels, regardless of acclimation status. Exogenous treatment with SA resulted in improvement in growth and survival of acclimated, chilled seedlings, indicating SA and acclimation have common effects. Cycloheximide treatment In the presence of SA restored acclimation-induced chilling tolerance. An elevated proline level was observed in cold-treated and SA- treated plants and the level was more pronounced in the light than in the dark at chilled temperature, indicating that endogenous proline may play a role in chilling tolerance.

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Mechanism of Arsenic-Induced Cytotoxiciht in CHO Cells (CHO 세포에서 비소의 세포독성기전)

  • 정해원;기혜성;박영철;한정호;유일재
    • Environmental Mutagens and Carcinogens
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    • v.16 no.2
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    • pp.117-123
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    • 1996
  • This study was carried out to examine the mechanism of Arsenic cytotoxicity through several in vitro test systems. Dose-dependent decrease of cell survival by Arsenic was observed by colony forming assay. Arsenic was weak mutagenic in inducing HGPRT point mutation in CHO cells. The frequency of chromosomal aberrations increased in a dose-dependent manner and the most frequent type of chromosomal aberrations induced by Arsenic were chromatid type deletions. U!trafiltrates of culture media from CHO cells treated with Arsenic induced sister chromatid exchanges(SCE) in CHO cells and Arsenic was able to induce lipid peroxidation in CHO cells. The results suggested that the ultrafiltrates of media from CHO cells treated with Arsenic contain clastogenic factor(CF) and Iipid peroxidation might be involved in the formation of CF.

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Survival and growth of the red tide organism Cochlodinium polykrikoides after the addition of yellow loess

  • Lee, Young-Sik;Lim, Wol-Ae;Lee, Sam-Geun
    • Proceedings of the Korean Environmental Sciences Society Conference
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    • 2008.11a
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    • pp.282-285
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    • 2008
  • At least 15% of the C polykrikoides cells that precipitated to the bottom layer either by the addition of loess or no addition survived for 1 week at all growth phases, rather than disappearing immediately after precipitating. However, no live cells were observed after 20 days, regardless of phase or loess addition. In the exponential phase, the number of C polykrikoides cells increased to >2886 cells/ml after loess was added. However, in the stationary phase, the number of cells did not increase until 18 days. In the exponential phase, those C polykrikoides that survived precipitation caused by scattering loess on cultures did not appear to have the ability to cause red tides again because of the short red tide periods in the field, long lag time after loess addition, and low survival rate after loess addition.

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Comparison of Haseman-Elston Linkage Tests with Age-of-Onset or Affection Trait

  • Jung, Kyoung-Hee;Song, Hae-Hiang
    • Communications for Statistical Applications and Methods
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    • v.13 no.3
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    • pp.635-649
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    • 2006
  • In this paper, we perform a simulation study of genetic model-free age-of-onset methods in linkage tests which has been proposed by Zhu et al. (1997). They performe. Haseman-Elston regression on a set of bipolar pedigree data using each of three dependent variables: a binary trait indicating disease concordance or discordance, a binary trait adjusted for age-of-onset, and the residuals from a survival analysis. We compare the powers of the proposed test statistics for various situations. Simulations that we have carried out show that the gains in power are observed when the residuals from a survival analysis are used in linkage tests.

A Joint Frailty Model for Competing Risks Survival Data (경쟁위험 생존자료에 대한 결합 프레일티모형)

  • Ha, Il Do;Cho, Geon-Ho
    • The Korean Journal of Applied Statistics
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    • v.28 no.6
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    • pp.1209-1216
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    • 2015
  • Competing-risks events are often observed in a clustered clinical study such as a multi-center clinical trial. We propose a joint modelling approach via a shared frailty term for competing risks survival data from a cluster. For the inference we use the hierarchical likelihood (or h-likelihood), which avoids an intractable integration. We derive the corresponding h-likelihood procedure. The proposed method is illustrated via the analysis of a practical data set.

Survival of Miamiensis avidus (Ciliophora: Scuticociliatia) from antibody-dependent complement killing

  • Lee, Eun Hye;Kang, Yue Jai;Kim, Ki Hong
    • Journal of fish pathology
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    • v.28 no.3
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    • pp.171-174
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    • 2015
  • Previously, we had reported that some Miamiensis avidus, a major pathogen of scuticociliatosis in cultured olive flounder, strongly agglutinated by flounder immune sera could escape from the agglutinated mass within a few hours. In the present study, we observed that M. avidus not only escaped from the agglutinated mass but also conducted division(s) before shedding its old covering. Furthermore, ciliates that survived the antibody-dependent complement killing (ADCK) assay were not killed even when re-exposed to a freshly prepared ADCK assay. This result suggests that the liberated ciliates from the ADCK assay might change not only their i-antigen types but also the epitopes of major surface antigens, which debilitate antibody-mediated complement killing ability.

A Study on Surgical Treatment of Thymoma -Analysis of 18 Cases- (흉선종의 외과적 치료에 대한 연구 -18례 분석-)

  • 이형렬
    • Journal of Chest Surgery
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    • v.27 no.4
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    • pp.303-309
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    • 1994
  • Eighteen patients with thymoma have undergone surgical treatment at Pusan National university Hospital from 1983 to 1993. The mean age of the patients was 47.3$\pm$13.3 years old and male to female ratio was 1.6 : 1. Eleven of the patients[61.1%] with thymoma had myasthenia gravis; 12 cases[66.7%] were encapsulated and 6[33.3%] invasive. Operation was complete resection in 14[77.8%] of the patients, partial resection with residual tumor in 3[16.7%], and simple biopsy in one[5.5%]. Adjuvant radiotherapy was administered in 5 of 6 invasive thymoma. Postoperatively one patient died for excessive bleeding and sepsis. A tumor relapse was observed in one patient who had invasive thymoma and underwent partial resection followed by postoperative radiotherapy. The overall 5-year survival rate was 88.2$\pm$ 7. 9%.The presence of myasthenia gravis is not considered as an adverse factor for survival but it contributes to early discovery of associated thymoma.

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Bootstrap Confidence Intervals for an Adjusted Survivor Function under the Dependent Censoring Model

  • Lee, Seung-Yeoun;Sok, Yong-U
    • Communications for Statistical Applications and Methods
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    • v.8 no.1
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    • pp.127-135
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    • 2001
  • In this paper, we consider a simple method for testing the assumption of independent censoring on the basis of a Cox proportional hazards regression model with a time-dependent covariate. This method involves a two-stage sampling in which a random subset of censored observations is selected and followed-up until their true survival times are observed. Lee and Wolfe(1998) proposed an adjusted estimate of the survivor function for the dependent censoring under a proportional hazards alternative. This paper extends their result to obtain a bootstrap confidence interval for the adjusted survivor function under the dependent censoring. The proposed procedure is illustrated with an example of a clinical trial for lung cancer analysed in Lee and Wolfe(1998).

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