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Han-liang Chang 《Biosemiotics》2012,5(3):301-312
In his well-known essay, ??What Is a Sign???(CP 2.281, 285) Peirce uses ??likeness?? and ??resemblance?? interchangeably in his definition of icon. The synonymity of the two words has rarely, if ever, been questioned. Curiously, a locus classicus of the pair, at least in F. M. Cornford??s English translation, can be found in a late dialogue of Plato, namely, the Sophist. In this dialogue on the myth and truth of the sophists?? profession, the mysterious ??stranger??, who is most likely Socrates?? persona, makes the famous distinction between eikon (likeness) and phantasma (semblance) (236a,b). For all his broad knowledge in ancient philosophy, Peirce never mentioned this parallel; nor has any Peircean scholar identified it. There seems to be little problem with eikon as likeness, but phantasma may give rise to a puzzle which this paper will attempt to solve. Plato uses two pairs of words: what eikon is to phantasma is eikastikén (the making of likeness [235d]) to phantastikén (semblance making [236c]). In other words, icons come into being because of the act of icon-making, which is none other than indexicality. Witness what Peirce says about the relationship between photographs and the objects they represent: ??But this resemblance is due to the photographs having been produced under such circumstances that they were physically forced to correspond point by point to nature.?? (Ibid.) Thus the iconicity which links the representamen (sign) and its object is made possible not only by an interpretant, but also by idexisation. Their possible etymological and epistemological links aside, the Peircean example of photographing and the Platonic discussion of painting and sculpturing in the Sophist, clearly show the physio-pragmatic aspect of iconicity. The paper will therefore reread the Peircean iconicity by closely analysing this relatively obscure Platonic text, and by so doing restore to the text its hidden semiotic dimension. 相似文献
84.
Background
Many molecules are flexible and undergo significant shape deformation as part of their function, and yet most existing molecular shape comparison (MSC) methods treat them as rigid bodies, which may lead to incorrect shape recognition. 相似文献85.
The effect of T-independent (TIA) and T-dependent (IDA) antigens on the surface Ig of 24-hr cultured rabbit spleen cells was investigated by two techniques: the proportion of cells bearing surface Ig was determined by direct rosette formation with anti-light chain allotype-coated erythrocytes; the total amount of surface Ig was estimated by labeling the cells with anti-allotype 125I-labeled Fab fragments. The addition of TIA resulted in the maintenance of the proportion of Ig-bearing cells almost to the initial level, an effect which could not be obtained with any of the TDA tested. The same type of effect was observed when the total amount of surface Ig was measured, i.e., there was a slight reduction (about 24%) in the amount of surface Ig in cultures to which TIAs were added and an almost sixfold reduction (about 70%) in cultures to which TDA, Con A, or no antigen was added. Some but not all of the TIA were able to induce [3H]TdR incorporation in 3-day spleen-cell cultures. We concluded that the common feature of TIA is the ability to stimulate the turnover of B-cell surface Ig, a feature that can be used for an easy screening of TIA. 相似文献
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Yu-Chi Su Goutham Venkata Naga Davuluri Cheng-Hao Chen Dong-Che Shiau Chien-Chin Chen Chia-Ling Chen Yee-Shin Lin Chih-Peng Chang 《PloS one》2016,11(2)
Hepatocellular carcinoma (HCC) is one of the most common cancers in Taiwan. Although chemotherapy is the primary treatment for HCC patients, drug resistance often leads to clinical failure. Galectin-1 is a beta-galactoside binding lectin which is up-regulated in HCC patients and promotes tumor growth by mediating cancer cell adhesion, migration and proliferation, but its role in chemoresistance of HCC is poorly understood. In this study we found that galectin-1 is able to lead to chemoresistance against cisplatin treatment, and subsequent inhibition has reversed the effect of cell death in HCC cells. Moreover, galectin-1 was found to induce autophagic flux in HCC cells. Inhibition of autophagy by inhibitors or knockdown of Atg5 cancels galectin-1-induced cisplatin resistance in HCC cells. Increase of mitophagy triggered by galectin-1 was found to reduce the mitochondrial potential loss and apoptosis induced by cisplatin treatment. Finally, using an in situ hepatoma mouse model, we clearly demonstrated that inhibition of galectin-1 by thiodigalactoside could significantly augment the anti-HCC effect of cisplatin. Taken together, our findings offer a new insight into the chemoresistance galectin-1 causes against cisplatin treatment, and points to a potential approach to improve the efficacy of cisplatin in the treatment of HCC patients. 相似文献
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89.
Xingyu Zhu Qianqian Gao Genhua Zhao Heng Wang Ling Liu Zhipeng Chen Yijun Chen Li Wu Zisheng Xu Weidong Li 《Biological trace element research》2018,184(1):136-147
To evaluate and compare the effect of raw and processed pyritum on tibial defect healing, 32 male Sprague Dawley rats were randomly divided into four groups. After tibial defect, animals were produced and grouped: sham and control group were orally administrated with distilled water (1 mL/100 g), while treatment groups were given aqueous extracts of raw and processed pyritum (1.5 g/kg) for successive 42 days. Radiographic examination showed that bone defect healing effect of the treatment groups was obviously superior compared to that of the control group. Bone mineral density of whole tibia was increased significantly after treating with pyritum. Inductively coupled plasma-optical emission spectrometry showed that the contents of Ca, P, and Mg in callus significantly increased in the treatment groups comparing with the control. Moreover, serological analysis showed that the concentration of serum phosphorus of the treatment groups significantly increased compared with that of the control group. By in vitro study, we have evaluated the effects of drug-containing serum of raw and processed pyritum on osteoblasts. It was manifested that both the drug-containing sera of raw and processed pyritum significantly increased the mRNA levels of alkaline phosphatase and collagen type I. Protein levels of phosphorylated Smad2/3 also increased. The mRNA levels of osteocalcin and transforming growth factor β (TGF-β) type I and II receptors, as well as the protein levels of TGF-β1 in the processed groups, were higher than those in the control. In summary, both raw and processed pyritum-containing sera exhibited positive effects on osteoblasts, which maybe via the TGF-β1/Smad signaling pathway. Notably, the tibia defect healing effect of pyritum was significantly enhanced after processing. 相似文献
90.