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991.
A rust fungus was described fromSchrebera swietenioides (Oleaceae) collected in India. The fungus possessed densely paraphysate uredinia and subepidermal, crustose telia with irregulary
5–7-layered sessile teliospores. These morphologies are characteristic ofPhakopsora, although noPhakopsora species had been reported from the family Oleaceae. The fungus was concluded to be a new species and a name,Phakopsora schreberae, was proposed for the new species. 相似文献
992.
Toshiro Kageshita Yoko Funasaka Masamitsu Ichihashi Kazumasa Wakamatsu Shosuke Ito Tomomichi Ono 《Pigment cell & melanoma research》2001,14(3):195-200
Not only does tissue factor (TF) play a crucial role in hemostasis and thrombosis, but it is also involved in tumor progression and metastatic potency in some malignant tumors. We evaluated the clinical relevance of TF expression in melanocytic tumors and TF serum level in patients with malignant melanoma. TF expression in benign and malignant melanocytic lesions was examined by immunoperoxidase staining in 20 nevi, 41 primary, and 24 metastatic melanoma lesions. TF was detected in 94, 95, and 100% of these lesions, respectively. The staining pattern was membranous and cytoplasmic both in nevi and melanoma cells. This finding was confirmed by western blot analysis using cultured human melanocytes, nevi cells, and melanoma cell lines. TF was also expressed on blood vessels in benign and malignant melanocytic lesions. Expression of TF in primary melanoma lesions was not associated with any clinicopathological variables. In addition, the serum level of TF was elevated in 14% of patients with melanoma; however, it was not correlated with disease progression. These results suggest that TF was ubiquitously expressed in melanocytic cells and its expression was not correlated with disease progression and/or metastatic potency of melanoma cells. 相似文献
993.
The emetic activity of staphylococcal enterotoxins,SEK, SEL,SEM, SEN and SEO in a small emetic animal model,the house musk shrew 下载免费PDF全文
Hisaya K. Ono Shouhei Hirose Ikunori Naito Yusuke Sato'o Krisana Asano Dong‐Liang Hu Katsuhiko Omoe Akio Nakane 《Microbiology and immunology》2017,61(1):12-16
Staphylococcal enterotoxins (SEs) produced by Staphylococcus aureus are the most recognizable causative agents of emetic food poisoning in humans. New types of SEs and SE‐like (SEl) toxins have been reported. Several epidemiological investigations have shown that the SEs and SEl genes, particularly, SEK, SEL, SEM, SEN and SEO genes, are frequently detected in strains isolated from patients with food poisoning. The purpose of the present study was to evaluate the emetic activity of recently identified SEs using a small emetic animal model, the house musk shrew. The emetic activity of these SEs in house musk shrews was evaluated by intraperitoneal administration and emetic responses, including the number of shrews that vomited, emetic frequency and latency of vomiting were documented. It was found that SEs induce emetic responses in these animals. This is the first time to demonstrate that SEK, SEL, SEM, SEN and SEO possess emetic activity in the house musk shrew. 相似文献
994.
Masahiro Fukuta Atsushi Ono Yasunori Nawa Wataru Inami Lin Shen Yoshimasa Kawata Susumu Terekawa 《Journal of biophotonics》2017,10(4):503-510
Label‐free optical nano‐imaging of dendritic structures and intracellular granules in biological cells is demonstrated using a bright and homogeneous nanometric light source. The optical nanometric light source is excited using a focused electron beam. A zinc oxide (ZnO) luminescent thin film was fabricated by atomic layer deposition (ALD) to produce the nanoscale light source. The ZnO film formed by ALD emitted the bright, homogeneous light, unlike that deposited by another method. The dendritic structures of label‐free macrophage receptor with collagenous structure‐expressing CHO cells were clearly visualized below the diffraction limit. The inner fiber structure was observed with 120 nm spatial resolution. Because the bright homogeneous emission from the ZnO film suppresses the background noise, the signal‐to‐noise ratio (SNR) for the imaging results was greater than 10. The ALD method helps achieve an electron beam excitation assisted microscope with high spatial resolution and high SNR.
995.
Ikeda Kazunori Ono Masahiro Akiyama Hideo Onizuka Takuo Tanaka Satoshi Miyasaka Hitoshi 《World journal of microbiology & biotechnology》2002,18(1):55-56
The transformation of the fresh water cyanobacterium Synechococcus PCC7942 with the shuttle-vector pAQ-EX1 developed for the marine cyanobacterium S. PCC7002 was examined. The S. PCC7942 cells were successfully transformed with the pAQ-EX1 vector, and the vector was stably maintained in the transformant cells. 相似文献
996.
997.
Hydroxyapatite for use as an animal cell culture substratum obtained by an alternate soaking process 总被引:1,自引:0,他引:1
Hiroyuki Ijima Tomokazu Ohchi Tsutomu Ono Koei Kawakami 《Biochemical Engineering Journal》2004,20(2-3):155-161
Hydroxyapatite (HAp), the major inorganic component of hard tissues in vivo, was formed in/on a PVA gel. The HAp formation ratio depended on the reaction cycle number, but was independent of the alternate soaking period per cycle. The Ca/P molar ratio of HAp formed at 10 reaction cycles was very close to the theoretical value of HAp, 1.67. CHO-K1 cell adhesion, proliferation and maximum cell density on HAp plates were better on plates formed at two or five reaction cycles using 200 mM CaCl2 and 120 mM Na2HPO4 solutions than on plates formed under other conditions. Furthermore, the adhesion ratio of CHO-K1 cells on HAp plates formed at 10 reaction cycles was about 60% of those at two or five reaction cycles. 相似文献
998.
Masaru Ito Yoko Kawa Hidenori Watabe Hirotake Ono Shiho Ooka Masayuki Nakamura Yoshinao Soma Masako Mizoguchi 《Pigment cell & melanoma research》2004,17(6):643-650
We devised a unique new single‐cell cloning method which uses microscope cover glasses and established a melanoblast cell line derived from mouse neural crest cells. A microscope cover glass was nicked and broken into small pieces and put on a dish. Culture medium and a suspension of 20–30 cells/ml were dropped in the dish. After 1–3 d, a piece of glass to which only one cell was adhered was picked up and transferred to another dish containing culture medium. The greatest advantage of this method is that the derivation of a colony from a single cell can be directly confirmed by microscopy and there is no risk of migratory cells being contaminated by other colonies. Using this single‐cell cloning method, in this study we established a cell line derived from a neural crest cell line (NCC‐S4.1) and designated it as NCCmelb4. When the culture medium was supplemented with stem cell factor (SCF) alone, NCCmelb4 cells were KIT‐positive and tyrosinase‐negative melanocyte precursors; they remained at an immature and undifferentiated stage. When the medium was supplemented with phorbol 12‐o‐tetradecanoyl‐13‐acetate (TPA) + cholera toxin (CT), the cell morphology changed and became l ‐3,4‐dihydroxyphenylalanine (DOPA)‐positive. This observation indicates that the NCCmelb4 cells are capable of further differentiation with suitable stimulation. NCCmelb4 cells derived from the mouse neural crest has characteristics of melanocyte precursors (melanoblasts), and is a cell line which can be utilized to study differentiation‐inducing factors and growth factors without the effects of feeder cells. 相似文献
999.
1000.
Takehiko Ueyama § Yi Ren Norio Sakai Mikiko Takahashi † Yoshitaka Ono † Takeshi Kondoh ‡ Norihiko Tamaki‡ Naoaki Saito 《Journal of neurochemistry》2001,79(4):903-913
PKN is a fatty acid- and Rho-activated serine/threonine kinase, which has a catalytic domain highly homologous to that of protein kinase C (PKC). Recent studies have demonstrated that PKN is proteolytically cleaved after apoptotic stimulation and then a constitutively active 55-kDa fragment is generated. However, the role of the 55-kDa fragment are poorly understood. Adult Sprague-Dawley (SD) rats underwent middle cerebral artery occlusion (MCAO), and the temporal and spatial changes in the fragmentation of PKN and of PKC delta were examined by immunoblotting. No proteolytic fragment of PKC delta (about 40 kDa) was detected. The 55-kDa fragment of PKN appeared transiently from 3 days after MCAO at the ipsilateral normal cortex. At the boundary zone of infarction, the 55-kDa fragment was markedly induced from day 5 then peaked on day 21 and persisted until day 28. Analysis of anti-phosphoserine immunoprecipitates with an anti-PKN antibody revealed phosphorylation of the 55-kDa band. Double staining for PKN and Ox42 was used to examine the source of the 55-kDa fragment. PKN immunoreactivity was significantly increased in Ox42-positive cells (microglia/hematogenous macrophages). No DNA laddering and only a few terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL)-positive cells were observed on day 14 in despite of the high level appearance of the 55-kDa band. These results suggest that the constitutively active 55-kDa fragment of PKN does not contribute to apoptosis, but may contribute to a function of microglia/macrophages. 相似文献