725 research outputs found
Effects of Sex-steroid Hormones on Lymphocyte Genesis in the Central Lymphoid Organs of Chickens
Lymphocytes play essential roles as a kind of leukocyte in the defense mechanism of animals against infectious factors. Lymphocytes are classified into two subsets, T lymphocytes and B lymphocytes in mammals or avian species. In avian species, T lymphocytes differentiate and proliferate in the thymus which is a central lymphoid organ common to mammalians and avian species, whereas on the other hand, B lymphocytes have been known to occur in the bursa of Fabricius (bursa) which is a unique central lymphoid organ of birds. Steroid hormones, such as androgen and estrogen, have been reported to change differentiations and proliferations of these lymphocytes in corresponding lymphoid organs, indicating steroid hormones give influence lymphocyte development positively or negatively in the bursa and thymus of birds. Studying the relation between steroid hormones and lymphocyte development in the central lymphoid organs is important, because changes in the lymphocyte genesis in central organs of birds may result in altered levels of antibody production and immune functions related to T lymphocyte activity. We have studied effects of androgen and estrogen on lymphocyte differentiation and proliferation in the central lymphoid organs of chicken at Okayama University since the 1980s. In the present report, the results of these studies are summarized
Research on Programs for Abusive Parents in Japan and Korea(2)
This study follows Research into Programs for Abusive Parents in Japan and Korea (1), published in March 2011. The paper clarified the following two points: 1) the characteristics of child abuse in Japan and Korea and legal provisions for the parents, and 2) the content of programs for parents in Japan and Korea. This study examines the characteristics of child abuse programs in Japan and Korea, featuring five points, as a follow-up to the previous paper. These five points are as follows: 1) limitations of parent training based on behavioral therapy, 2) human relationship of healing, 3) resolving the internal conflict in the past and present, 4) the culture of the parent–child relationship and partner relationships in Japan and Korea, and 5) group work and empowerment
キラルリチウムアミドによる不斉還元を利用した新規合成反応の開発
広島大学(Hiroshima University)博士(薬科学)Doctor of Philosophy in Medicinal Sciencedoctora
Observation of the Fano-Kondo Anti-Resonance in a Quantum Wire with a Side-Coupled Quantum Dot
We have observed the Fano-Kondo anti-resonance in a quantum wire with a
side-coupled quantum dot. In a weak coupling regime, dips due to the Fano
effect appeared. As the coupling strength increased, conductance in the regions
between the dips decreased alternately. From the temperature dependence and the
response to the magnetic field, we conclude that the conductance reduction is
due to the Fano-Kondo anti-resonance. At a Kondo valley with the Fano parameter
, the phase shift is locked to against the gate voltage
when the system is close to the unitary limit in agreement with theoretical
predictions by Gerland {\it et al.} [Phys. Rev. Lett. {\bf 84}, 3710 (2000)].Comment: 4 pages, 4 figure
Rate of Heat Transfer between a Fluidized Bed and the Tube Wall at Higher Temperature
The heat transfer coefficient between a fluidized bed and the tube wall, hw, was measured in the temperature range of 500° to 800°C. Quartz and fused alumina particles were fluidized in the air stream. The coefficient hw was obtained between 70 and 800 kcal/m²·hr·°C. It increases with the flow rate of air. The effects of bed temperature and heat content and size of the particles on hw were imperceptible. By comparing the heat transfer coefficients obtained in this work with those at lower temperatures below 200°C, the difference between both coefficients was not significant
Animal Experiment on Functional Features of Eggs Stated to be Hypoallergenic for People with Food Allergies
Functional features concerned with low proallergic natures were examined using an allergy-inducible rat strain (Brown Norway rat; BN rat) on hen's eggs which have been empirically mentioned as hypoallergenic
for patients suffering from food allergies (experimental eggs). BN rats were fed on feed containing
whole experimental eggs (feed E) and whole normal eggs (control feed, feed C). The densities of immunoglobulin E (IgE)-positive cells, have reported to be IgE-bearing mast cells, in the jejunum and ileum of BN rats fed on experimental-egg-containing feed were lower than those of BN rats fed on normal-egg-containing feed. The number of blood eosinophils was also lower in BN rats fed on feed E. Serum IgE levels were no different between BN rats fed on feed E and feed C. These results indicate that the low proallergic nature of hen's eggs studied in the present study is due to the dereased ability of experimental eggs to facilitate the proliferation and induction of mast cells in the intestinal tissue.食物アレルギーを持つ消費者の経験に基づいて低アレルギー誘発性であることが言及されている鶏卵について,低アレルギー誘発性の有無と科学的な根拠を明らかにするために動物を用いた実験をおこなった.実験にはアレルギーを発症することが知られているラットの系統であるBrown Norway rat(BNラット)を用い,この鶏卵を混ぜ込んだ飼料で飼育した.対照として,市販の鶏卵(普通卵)で同様に飼育した.試験卵で飼育したBNラットでは,空腸と回腸組織のIgE陽性細胞の密度は普通卵で飼育した場合に比較して大きく低下した.組織中のIgE陽性細胞の大部分は肥満細胞であることが知られていることから試験卵群における小腸組織の肥満細胞密度は低下した.さらに,血中の好酸球数は同様に試験卵による飼育で低下した.一方,血清のIgE濃度には摂取させた卵による違いは認められなかった.以上の結果は,試験卵を摂取した場合,通常の卵の摂取に比較して即時型アレルギー症状の発生に直接的に関与する肥満細胞と好酸球の誘導や増殖が促進されにくいと考えられ,このことが,試験卵がアレルギーを引き起こしにくい一因であると推察される
Enhancement of norepinephrine-induced transient contraction in aortic smooth muscle of diabetic mice.
Changes in norepinephrine-induced transient contractions in Ca2+-deficient solution were investigated in the aortic smooth muscles of diabetic ALS (alloxan-induced diabetes susceptible) mice. The transient contractions in diabetic mice were significantly larger than those in normal mice. The longer incubation of the muscle preparations in Ca2+-deficient solution made the transient contractions smaller, probably due to the leakage and decrease in norepinephrine-releasable stored Ca2+. The rate of this reduction in contraction was slower in diabetic mice. These results suggest that the leakage of intracellular stored Ca2+ caused by extracellular Ca2+ deficiency is attenuated in diabetic mice, contributing to enhanced norepinephrine-induced transient contractions.</p
ニワトリ胚のファブリシウス嚢におけるBリンパ球の発達に対する sIgM 誘導因子の役割
The bursa of Fabricius plays essential roles in the establishment of immune functions of avian species as a primary site for differentiation and proliferation of B lymphocytes. The bursa of chick embryos is colonized by lymphoid cell precursors only between the days 7th of embryogenesis (E7) and E14. Susceptibility to the sIgM-inducing factor may fluctuate in bursal lymphoid
cells during the lymphoid precursor cell-receptive period. In the present study, the dynamic changes in the sIgM-positive ratio and responsiveness to sIgM-inducing factor were examined in lymphoid cells sampled from the bursa during the B precursor cell-receptive period (E10 to E13) and findings suggest that responsiveness to sIgM-inducing factor varies with the development of the chick embryos. E11 is suggested to be a critical stage of B-lymphocytegenesis in the bursa of
chick embryos.ファブリシウス嚢はBリンパ球分化と増殖のための中枢リンパ組織として鳥類の免疫機能の発達において重要な役割を演じている.培養ファブリシウス嚢上皮細胞は胚のファブリシウス嚢リンパ球に膜の IgM 分子(sIgM)の発
現を誘導する因子を産生することが報告されている.ファブリシウス嚢リンパ球の sIgM 発現誘導因子に対する感受性はファブリシウス嚢における分化の時期において変動する可能性が考えられる.ニワトリの胚では,リンパ球系の前駆細胞は胚発達の7日目から14日目の間においてのみファブリシウス嚢に進入・定着することが知られている.そこで本研究では,リンパ球系前駆細胞がファブリシウス嚢に定着するこの時期(10日胚から13日胚)におけるファブリシウス嚢リンパ球の sIgM 発現の変動を調べるとともに,これらの細胞における sIgM 発現誘導因子に対する感受性の変動について測定した.sIgM 陽性細胞の割合は11日胚で有意に上昇した.sIgM 発現誘導因子に対する反応性はこの時期の胚発達に伴って変動し,11日胚で高い傾向を示した.これらの結果から,11日胚齢はニワトリ胚のファブリシウス嚢におけるBリンパ球の発達に関して重要な時期であることが示唆された
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