• Title/Summary/Keyword: survial function

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A Modified Test for the Hollander and Proschan's Test Against Decreasing Mean Residual Life Alternatives

  • Kim, Hwan-Joong;Kim, Jae-Joo
    • Journal of Korean Society for Quality Management
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    • v.22 no.1
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    • pp.152-161
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    • 1994
  • In this paper we develop a test for alternatives representing decreasing mean residual life. The test statistic for decreasing mean residual life, $K_{1n}$, is a modified version of Hollander and Proschan's test $V^*$ and critical constants and large sample approximation are shown to make the test readily applicable. Consistency is also shown for the tests based on $K_{1n}$. And small sample powers for four alernatives are obtained.

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Experimental Study of Homotransplantation of Lung in Dogs (폐장이식에 관한 실험적 연구)

  • 김진식
    • Journal of Chest Surgery
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    • v.2 no.1
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    • pp.25-40
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    • 1969
  • Lung homotransplantation was performed in 15 pairs of dog. Methotrexate and R.E.S. blocking were used to prolong the survival time. Details of handling the transplant, operative technique and management of the recipient were discussed and following results were obtained: 1]. 7 dogs out of 15 dogs of homotransplantation of lung were survived beyond 3 days. In the group of dogs treated with methotrexate, the average survival was 8.5 days, and in the group of dogs treated with R.E.S. blocking, the average survial was 9.7 days with longest survival of 17 days. 2]. The causes of immediate postoperative death in homotransplantation of dogs were lung edema and disruption of bronchial anastomosis. 3]. The main causes of death in successful homotransplantation dogs which were survived beyond 3 days were infection of lung parenchyma and bronchial necrosis rather than the occurence of graft rejection. 4]. Graft rejection was not revealed even after 7 days of operation in the group treated with methotrexate as well as in the group treated with R. E.S. blocking. This finding made it suggest that the R. E.S. blocking may be effective to control the rejection reaction. 5]. Even though the pulmonary function of transplanted lung was revealed the evidence of severe impairment immediate after operation by bronchospirometry, it was increased gradually and 10 days after operation the minute ventilation and oxygen uptake were decreased 8%, 13% respectively less than pre-operative one.

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A STUDY OF CLINICAL RESULTS ON STERI-OSS ENDOSSEOUS IMPLANTS (Steri-Oss 임플랜트의 임상 결과에 관한 연구)

  • Min, Young-Kyu;Kweon, Hyeog-Sin;Chung, Chae-Heon
    • The Journal of Korean Academy of Prosthodontics
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    • v.36 no.2
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    • pp.258-272
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    • 1998
  • This investigation evaluated patients who received Steri-Oss implants from the Dental Hospital of Chosun University during the period from March 1989 to August 1997. 346 fixtures of 127 patients were included in this study. The results were as follows ; 1.The follow-up period was defined as the period between the surgical placement of the implants and the last follow-up examination. The mean follow-up period was $2.17{\pm}1.21$ years. 2.The period between fixture installation and second surgery was $0.71{\pm}0.44$ years in the maxilla and $0.46{\pm}0.21$ years in the mandible. 3.The number of fixtures which were installed in the upper jaw(112) was less than that in the lower jaw(234) and in the posterior region(260) was more than in the anterior region(86). 4.The length of fixture which was most frequently used was 12 mm and least was 8mm. Screw implants were installed more than cylindrical implants. 3.8mm implant was the most common implans, followed by 4.5mm and 3.25mm. 5.The number of augmentation cases was more than that of non-augmentation cases and the rate of augmentation cases in the maxilla was more than that in the mandible. 6.Implant restorations for partial edentulos patients(94cases) were more than single- tooth implant restorations(33cases) or implant restorations for complete edentulos patients(10cases). 7.Free-standing prostheses for partially edentulous patients were more commom than any other type of connection between implants and natural teeth. 8.Plaque Index($0.95{\pm}0.74$) and Gingival Index($0.31{\pm}0.52$) were very similar around the natural teeth and reflected an acceptable level of plaque and gingivitis control. Mean value for keratinized mucosa index($1.93{\pm}1.20$) remained fairly constant around level 2(1-2 mm keratinized epithelium). 9.Patients were generally satisfied with implant in terms of comfort, function, speech and esthetics. 10.There was not a statistically significant differences in overall survial rate between implants placed in the maxilla (91.5%) and those placed in the mandible (93.8%). Fourteen implants lost before the prosthetic rehabilitation and eleven implants lost following variable periods in function after the prosthetic phase of the treatment. 11.Cause of implant failures was exfoliation or removal of fixture due to non-osseointegration before the prosthetic rehabilitation or due to fracture of fixture, masticatory pain after the prosthetic rehabilitation. 12.The survival rate of Steri-Oss implants using the Kaplan-Meier statistical analysis was 93.8% at 2 year and 86.6% at 5 year, In all cases, implant losses occured predominantly in the healing period. There was a steep decline in the rate of implant loss after the first year. 13.The survival rate of Steri-Oss implants in the anterior region was 94.8% at 2 year and 94.8% at 5 year and that in the posterior region was 92.8% at 2 year and 75.9% at 5 year. In conclusion, this study revealed a number of parameters and guidelines for achieving an optimal success rate in osseointegration.

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Gastric Acid Resistance of Lactobacilli and Bifidobacteria in Commercial Drink and Liquid Yogurts (시판 드링크 및 액상 요구르트 제품중 Lactobacilli 및 Bifidobacteria의 내산성 연구)

  • Cui Jing-Hao
    • Korean Journal of Microbiology
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    • v.36 no.2
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    • pp.161-165
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    • 2000
  • Gastric acid resistance of aerobic Lactobacilli and anaerobic Bifidohacteria in commercial 19 drink and 18 liquid yogurts in Korea was investigated after exposure to simulated gastric fluid (pH 1.5). The initial survival of Lactobacilli in commercial drink and liquid yogurts was $10^8~10^{10}$ cfulml and $10^6~10^{10}$cfdml, respectively. On the other hand, the initial survival of Bifidobacteria in commercial drink yogurts was ($10^6~10^{10}$cfulml. The survival of Lactobacilli and Bifidobacteria in some commercial drink and liquid yogurts drastically changed depending on the type of commercial products when exposed to simulated gastric fluid for 120 min (<$10^3~10^6$ cfulml). Their survival decreased as a function of time in the simulated gastric fluid. In the case of drink yogurt containing Bifidobacteria-loaded capsu1es;the survival of Bifidobactena in only Mi after excluding capsules was similar to other commercial drink yogurts after exposure to gastric fluid for 30-120 min (ca. TEX>$10^5$ cfulml). However, the survival of Bifidobacteria in capsules was greatly enhanced due to their stability in low pH condition (>$10^8$ cfulml). The drink yogut containing Bifidobacteria-loaded capsules showed about 10-737 times higher survival in the gastric fluid for 120 min when compared to other commercial drink yogurts. It was evident that the gastric acid resistance of Bifidobacteria could be increased when encapsulated.

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