• 제목/요약/키워드: biomedicine

검색결과 309건 처리시간 0.027초

임상시험에서 이분형 결측치 처리방법의 비교연구 (Comparison of binary data imputation methods in clinical trials)

  • 안구성;김동재
    • 응용통계연구
    • /
    • 제29권3호
    • /
    • pp.539-547
    • /
    • 2016
  • 임상시험에서 흔히 발생하는 결측치 중 이분형 결측치에 대한 논의를 하였다. 본 논문에서는 결측치가 발생하는 기재를 논의하고 기존의 여러 이분형 결측치 대체 방법과 수정된 결측치 대체방법을 소개하였다. 이후 각 결측치 대체 방법을 실제 자료에 적용하여 모의 실험을 진행하였다. 실제 자료의 성격 및 결측률의 변화에 따른 결측치 대체 방법들의 성능비교를 통해 진행하였다. 마지막으로 각 결측치 대체 방법에 대한 모의 실험 결과를 요약하고 토의하였다.

유효하고 안전한 용량 결정에 위치를 이용한 비모수적 방법 (Nonparmetric Method for Identifying Effective and Safe Doses using Placement)

  • 김선혜;김동재
    • 응용통계연구
    • /
    • 제27권7호
    • /
    • pp.1197-1205
    • /
    • 2014
  • 일반적으로 약제 용량 결정 연구는 대조군과 여러 용량 수준을 비교하여 유효성과 안전성을 동시에 만족하는 약물의 치료 범위(therapeutic window)를 찾아내는 데에 관심이 있다. 이 논문에서는 안전성과 유효성을 동시에 만족하는 용량 결정을 위하여 선형 위치(linear placement)에 점수함수(score function)를 이용한 비모수적 검정법을 제안하였다. 또한 Monte Carlo 모의실험을 통하여 기존의 모수적 방법들과 검정력(power)과 FWE(family-wise error rate)를 비교하였다.

고삼에서 항균물질의 분리 (Isolation of Antimicrobial Active Substances from Sophorae Radix)

  • 김윤경;한완수;정승일;이기남;김현주;이정호
    • 대한예방한의학회지
    • /
    • 제9권1호
    • /
    • pp.135-141
    • /
    • 2005
  • Bioassay-directed fractionation of the dired roots of Sophorae Radix led to the isolation of Sophoraflavanone G. Their structures were elucidated using 1H-NMR, 13C-NMR, UV, IR and mass spectral ananlyses. These compounds exhibited a moderate antimicrobial activities against Streptococcus gordonii, Actinobacillus actinomycetemoomitans and Porphylomonas gingivalis.

  • PDF

Biological control of Flavobacterium psychrophilum infection in ayu (Plecoglossus altivelis altivelis) using a bacteriophage PFpW-3

  • Kim, Ji Hyung;Park, Se Chang
    • 대한수의학회지
    • /
    • 제58권1호
    • /
    • pp.39-43
    • /
    • 2018
  • The efficacy of using a bacteriophage (phage) to control Flavobacterium psychrophilum (F. psychrophilum) infection of ayu (Plecoglossus altivelis altivelis) was evaluated in this study. Intramuscular challenge failed to induce sufficient infection levels; therefore, a newly designed net-scratch challenge method was also used to induce bacterial infection. Administration of phage PFpW-3 in F. psychrophilum-infected ayu showed notable protective effects, increased survival rates and mean times to death. Additionally, the fate of inoculated bacteria and phage in ayu were investigated. Our results suggest that the phage PFpW-3 could be considered an alternative biocontrol agent against F. psychrophilum infections in ayu culture.

Synthetic bio-actuators and their applications in biomedicine

  • Neiman, Veronica J.;Varghese, Shyni
    • Smart Structures and Systems
    • /
    • 제7권3호
    • /
    • pp.185-198
    • /
    • 2011
  • The promise of biomimetic smart structures that can function as sensors and actuators in biomedicine is enormous. Technological development in the field of stimuli-responsive shape memory polymers have opened up a new avenue of applications for polymer-based synthetic actuators. Such synthetic actuators mimic various attributes of living organisms including responsiveness to stimuli, shape memory, selectivity, motility, and organization. This article briefly reviews various stimuli-responsive shape memory polymers and their application as bioactuators. Although the technological advancements have prototyped the potential applications of these smart materials, their widespread commercialization depends on many factors such as sensitivity, versatility, moldability, robustness, and cost.

일원배치법에서 결합위치를 이용한 비모수 검정법 (Nonparametric method in one-way layout based on joint placement)

  • 전경아;김동재
    • 응용통계연구
    • /
    • 제29권4호
    • /
    • pp.729-739
    • /
    • 2016
  • 독립된 세 개 이상의 처리 간에 차이 유무를 검정하는 비모수적 방법에는 Kruskal과 Wallis (1952)가 제안한 검정법이 있다. 세 개 이상의 다른 모집단으로부터 결합된 표본관측 값들의 순위를 이용한 검정기법이다. 본 논문에서는 Chung과 Kim (2007)이 제안한 결합위치 방법을 확장하여 일원배치모형에서 새로운 방법을 제안하였다. 또한 모의실험(Monte Calro simulation study)를 통하여 기존의 검정법과 제안한 방법의 검정력을 비교하였다.

Crystallographic and Magnetic Properties of Iron Oxide Nanoparticles for Applications in Biomedicine

  • Lee, Sang-Won;Woo, Kyoung-Ja;Kim, Chul-Sung
    • Journal of Magnetics
    • /
    • 제9권3호
    • /
    • pp.83-85
    • /
    • 2004
  • Magnetic nanoparticles have been investigated for use as biomedical purposes for several years. For biomedical applications the use of particles that present superparamagnetic behavior at room temperature is preferred [1-4]. To control the magnetic materials by magnetic field is essential locate particle to the suitable destination on feeding by injection. In order to use them properly, the particles should be nano size. However there are many difficulties in applications, because there is lack of identifications in nano magnetic properties. In our studies, structural and magnetic properties of iron oxide nanoparticles were investigated by XRD, VSM, TEM, and Mossbauer spectroscopy. At 13 K, hyperfine fields of ${\gamma}-Fe_2O_3$ were 516 kOe and 490 kOe, that of $Fe_3O_4$ were 517 kOe and 482 kOe. The saturation magnetizations were 21.42 emu/g and 39.42 emu/g. The particle size of powders is 5~19 nm.

Emerging Japanese Encephalitis Virus Genotype V in Republic of Korea

  • Lee, Ah-Ra;Song, Jae Min;Seo, Sang-Uk
    • Journal of Microbiology and Biotechnology
    • /
    • 제32권8호
    • /
    • pp.955-959
    • /
    • 2022
  • Japanese encephalitis (JE) is a vaccine-preventable mosquito-borne disease caused by infection with the Japanese encephalitis virus (JEV). JEV has five genotypes, including genotype V (GV), which is considered ancestral to the other genotypes. The first GV strain, GV Muar, was isolated from a Malayan patient in 1952 and GV did not reappear for 57 years until GV XZ0934 was isolated from a mosquito sample in China. Since 2010, 21 GV strains have been identified in Republic of Korea (ROK). Both GV Muar and GV XZ0934 are more pathogenic than other GI/GIII strains and are serologically distinct. However, because the ROK's GV strains have not been experimentally tested, their characteristics are not known. Characterization of the ROK's isolates is needed to enable development of effective GV strain-based vaccines to protect against GV infections.

Biomedical Application of Silk Sericin: Recent Research Trend

  • Seong-Gon Kim;Je-Yong Choi;HaeYong Kweon
    • International Journal of Industrial Entomology and Biomaterials
    • /
    • 제48권1호
    • /
    • pp.1-12
    • /
    • 2024
  • Silk sericin, a natural protein from silkworm cocoons, is emerging as a multifunctional biomaterial in biomedicine, particularly in tissue engineering and wound healing. Recent studies have highlighted its biocompatibility, biodegradability, and potential for chemical modification, which allows it to be incorporated into various scaffold architectures. This review article synthesizes current research, including the development of sericin-based hydrogel scaffolds for tissue engineering and sericin's role in enhancing wound healing. Key findings demonstrate sericin's ability to refine scaffold porosity and mechanical strength, expedite tissue healing, and reduce bacterial load in wounds. The integration of sericin into novel bioactive dressings and its use in peripheral nerve injury repair are also discussed, showcasing its adaptability and efficacy. The convergence of these studies illustrates the broad applications of sericin, from scaffold design to clinical interventions, making it a promising material in regenerative medicine and tissue engineering, with the potential to improve patient outcomes significantly.