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61.
Fifty-seven Shiga toxin-producing Escherichia coli (STEC) strains isolated from pigs with edema disease (ED) from 1997 to 2001 in Japan were examined for antimicrobial susceptibilities. The susceptibilities were compared with those of E. coli ATCC 23546 isolated from pig with ED in the 1950's. Consequently, the isolated STECs showed high susceptibility to peptides and bicozamycin in a way similar to the reference strain. On the other hand, the STECs showed low susceptibility to beta-lactams, tetracyclines, novobiocin, fosfomycin, trimethoprim, and old quinolones. It became clear that the susceptibilities of the isolated STECs had diminished in regard to antimicrobials. 相似文献
62.
Mamoru Tsukuda Taro Nagahara Yasukazu Mikami Tadayuki Yago Hideki Matsuda Shunsuke Yanoma 《Biotherapy》1993,6(3):217-223
From a patient, both a cell line incapable of secreting granulocyte colony-stimulating factor (G-CSF) (TC873) and a cell line capable of secreting G-CSF (TCM902) were established. The effector cells induced, with TC873 cells showed a high lytic capacity against two types of tumor cells. The effector cells induced by TCM902 cells did not show such capacity. Furthermore, the TCM902 cells excreted a factor suppressing the proliferation of lymphokine activated killer (LAK) cells and the autologous tumor cell lysis of tumor associated lymphocytes. This factor probably is TFG-
1.Abbreviations CSF
colony stimulating factor
- ELISA
enzyme-linked immunosorbent assay
- G
granulocyte
- GM
granulocyte-monocyte
- IFN
interferon
- IL
interleukin
- LAK
lymphokine activated killer
- M
monocyte
- MLTC
mixed lymphocyte tumor cell culture
- TGF
transforming growth factor
- TILs
tumor infiltrating lymphocytes
- TNF
tumor necrosis factor 相似文献
63.
Summary The use of antibodies to synthetic LH-RH has enabled the detection by immunofluorescence of hypothalamic LH-RH producing cells in the human fetus. The perikarya of these cells are located in the pericommissural and preoptic regions, in the lamina terminalis and in the premamillary region. Reactive axons occur in the median eminence. The first LH-RH producing cells are seen as early as nine weeks of gestation. The specificity of immunocytological reaction has been controlled. 相似文献
64.
J Skelly M Gacto M R Steiner S Steiner 《Biochemical and biophysical research communications》1976,68(2):442-449
Two fucose-containing lipids with long chain base as their apolar moiety are described. These compounds were shown to possess a free amino group and a net positive charge by derivatization with specific amino reagents and by cation exchange column chromatography. The presence of long chain base was demonstrated by periodate-NaB[3H]4 treatment to yield long chain alcohol and by [3H]-dansylation followed by hydrolysis to yield dansyl-long chain base. 相似文献
65.
Qingqing Xu Zhaoyang Liu Zhiqiang Cao Yongjian Shi Ning Yang Guangshang Cao Chunmin Zhang Rong Sun Chunhong Zhang 《Journal of cellular and molecular medicine》2022,26(4):1281
Astilbin, an essential component of Rhizoma smilacis glabrae, exerts significant antioxidant and anti‐inflammatory effects against various autoimmune diseases. We have previously reported that astilbin decreases proliferation and improves differentiation of HaCaT keratinocytes in a psoriatic model. The present study was designed to evaluate the potential therapeutic effects of topical administration of astilbin on an imiquimod (IMQ)‐induced psoriasis‐like murine model and to reveal their underlying mechanisms. Topical administration of astilbin at a lower dose alleviated IMQ‐induced psoriasis‐like skin lesions by inducing the differentiation of epidermal keratinocytes in mice, and the therapeutic effect was even better than that of calcipotriol. Moreover, the inflammatory skin disorder was relieved by astilbin treatment characterized by a reduction in both IL‐17‐producing T cell accumulation and psoriasis‐specific cytokine expression in skin lesions. Furthermore, we found that astilbin inhibited R837‐induced maturation and activation of bone marrow‐derived dendritic cells and decreased the expression of pro‐inflammatory cytokines by downregulating myeloid differentiation factor 88. Our findings provide the convincing evidence that lower doses of astilbin might attenuate psoriasis by interfering with the abnormal activation and differentiation of keratinocytes and accumulation of IL‐17‐producing T cells in skin lesions. Our results strongly support the pre‐clinical application of astilbin for psoriasis treatment. 相似文献
66.
草鱼肾脏和脾脏血细胞发育过程的观察 总被引:40,自引:7,他引:33
鱼类肾脏、脾脏是机体造血的主要器官。印迹涂片显示:草鱼肾脏和脾脏内血细胞的发育过程大致经历了三个阶段,即原始阶段、幼稚阶段、成熟阶段。本文着重描述了各阶段细胞的形态特征井对草鱼血细胞的发育及命名等问题作了初步的探讨。
相似文献
67.
68.
本文对代谢工程的发展状况从研究方法,在医药、农业及环保中应用等几方面做了概括地介绍;从宿主的选择,加速限速反应,改变代谢流和生产程序的优化几方面较为详细地评述了代谢工程在苯丙氨酸基因工程菌构建方面的应用,并对代谢工程的未来发展进行了展望。 相似文献
69.
Tyrosine hydroxylase (TH) is the first and rate-limiting enzyme in dopamine synthesis. Dopamine regulates TH as an end-product inhibitor through its binding to a high and low affinity site, the former being abolished by Ser40 phosphorylation only, and the latter able to bind and dissociate according to intracellular dopamine levels. Here, we have investigated TH inhibition by a dopamine metabolite found in dopaminergic brain regions, salsolinol (SAL). SAL is known to decrease dopamine in the nigrostriatal pathway and mediobasal hypothalamus, and to also decrease plasma catecholamines in rat stress models, however a target and mechanism for the effects of SAL have not been found. We found that SAL inhibits TH activity in the nanomolar range in vitro, by binding to both the high and low affinity dopamine binding sites. SAL produces the same level of inhibition as dopamine when TH is non-phosphorylated. However, it produces 3.7-fold greater inhibition of Ser40-phosphorylated TH compared to dopamine by competing more strongly with tetrahydrobiopterin, the cofactor of this enzymatic reaction. SAL’s potent inhibition of phosphorylated TH would prevent TH from being fully activated to synthesise dopamine. 相似文献
70.