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51.
This essay documents the main currents of visual studies in communication. After a brief history of the emergence of the field, we review the record of published research in books and journals during the past 5 years, identifying major strains of theory, key issues, and topical categories. We then apply the strains of thought to classify papers presented at the ICA conferences, noting patterns and shifts across and within ICA divisions and interest groups. Based on these patterns, as well as on informal input from colleagues, we map the discipline formation of visual studies and identify trends in institutional development. We conclude by exploring future directions for the field now that the visual interest group has grown to become the Visual Studies Division of ICA.  相似文献   
52.
选择天然产物齐墩果酸进行炔基化修饰(OA-alkyne),与环金属铱前体CycloIr-N3在铜催化条件下发生叠氮-炔环加成(CuAAC)反应,得到新的环金属铱配合物CycloIr-OA,通过1H NMR、ESI-MS对配体及配合物进行了表征。配合物具有良好的脂溶性,可以快速进入细胞。用MTT法、激光共聚焦成像及流式细胞术对CycloIr-OA的抗肿瘤活性和抗癌机制进行了研究。结果表明,连接齐墩果酸后,配合物CycloIr-OA的抗癌活性有较大提升。CycloIr-OA富集在肿瘤细胞的线粒体中,导致活性氧产生,同时将细胞周期阻滞在S期,最终诱导肿瘤细胞坏死。  相似文献   
53.
The study of popular communication is carried out in many disciplines and many sites. It is often haunted by anxieties over high culture versus low culture and authenticity versus commercialization. Rejecting those binaries in favor of the dominance of the latter term in each, this article initially defines popular communication as objects widely circulated by mass media, texts to which people are widely exposed. Such texts are themselves commodities, and the meanings the texts facilitate are key. Scholars of popular communication usually espouse a leftist political agenda. They focus on signs that reveal processes in social or psychological experience, although some studies focus more on forms of discourse. The article proposes that studies in popular communication may be distinguished by whether they focus on rhetor, text, or audience. It concludes by urging a stance of critical populism, more popular involvement by scholars, and a greater understanding of erotics, or desire, in our work.  相似文献   
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55.
One of the common challenges in using glucocorticoid in the long term is the development of femoral head necrosis. To address this challenge, the use of glucocorticoid suppressors like plant polysaccharides has been considered. In this study, Moringa oleifera polysaccharide was isolated through hot water–ethanol precipitation method and purified by DEAE-Sepharose fast flow column. Then, they were characterized by FT-IR, NMR, methylation, and chromatography assays. The polysaccharide biocompatibility was investigated by MTT assay and its effect on osteoblasts was evaluated by controlling gene expression. Also, the effect of polysaccharide on dexamethasone-induced femoral head necrosis in rats was assessed by hydroxyproline, hexosamine and morphometric parameters. The results show that 2 Da molecular weight polysaccharide is mainly composed of Rha, Ara, Fru, Xyl, Man and Gal in the molar ratio of 1.7:2.1:3.4:5.9:5.8:1.3. Meanwhile, MTT results on osteoblasts cells showed polysaccharide biocompatibility, while significantly reducing the negative effects of glucocorticoid. Likewise, polysaccharide significantly reduced the levels of apoptosis and intracellular ROS of glucocorticoid-induced femoral necrosis. Moreover, the results of gene expression indicated a decrease in the expression of TNF-α and IL-6 genes using polysaccharide, which is very effective in preventing apoptotic activity. Also, Polysaccharide increased bone density, bone volume per tissue volume, trabecular thickness, and the hexosamine to hydroxyproline ratio in the rat serum in the presence of glucocorticoids, which are very effective in the process of femoral head necrosis. Furthermore, polysaccharide significantly increases the OCN, RUNX2 and COL-1 genes expression in cartilage tissue, which is in line with the result of morphometric parameters. Overall, this study suggests that the use of polysaccharide could result in the treatment of femoral head necrosis.  相似文献   
56.
Cancer has always been one of the most common malignant diseases in the world. Therefore, there is an urgent need to find potent agents with selective antitumor activity against cancer cells. It has been reported that antimicrobial peptides (AMPs) can selectively target tumor cells. In this study, we focused on the anti-tumor activity and mechanism of Brevivin-1RL1, a cationic α-helical AMP isolated from frog Rana limnocharis skin secretions. We found that Brevivin-1RL1 preferentially inhibits tumor cells rather than non-tumor cells with slight hemolytic activity. Cell viability assay demonstrated the intermolecular disulfide bridge contributes to the inhibitory activity of the peptide as the antitumor activity was abolished when the disulfide bridge reduced. Further mechanism studies revealed that both necrosis and apoptosis are involved in Brevivin-1RL1 mediated tumor cells death. Moreover, Brevivin-1RL1 induced extrinsic and mitochondria intrinsic apoptosis is caspases dependent, as the pan-caspase inhibitor z-VAD-FMK rescued Brevinin-1RL1 induced tumor cell proliferative inhibition. Immunohistology staining showed Brevivin-1RL1 mainly aggregated on the surface of the tumor cells. These results together suggested that Brevivin-1RL1 preferentially converges on the cancer cells to trigger necrosis and caspase-dependent apoptosis and Brevivin-1RL1 could be considered as a pharmacological candidate for further development as anti-cancer agent.  相似文献   
57.
Dipterocarpus tuberculatus Roxb. has been used traditionally as a remedy for many diseases, especially inflammation. Therefore, we analyzed and explored the mechanism of the anti-inflammatory effect of a Dipterocarpus tuberculatus Roxb. ethanol extract (Dt-EE). Dt-EE clearly and dose-dependently inhibited the expression of pro-inflammatory cytokines such as IL-6, TNF-α, and IL-1β in lipopolysaccharide (LPS)-treated RAW264.7 cells. Also, Dt-EE suppressed the activation of the MyD88/TRIF-mediated AP-1 pathway and the AP-1 pathway related proteins JNK2, MKK4/7, and TAK1, which occurred as a result of inhibiting the kinase activity of IRAK1 and IRAK4, the most upstream factors of the AP-1 pathway. Finally, Dt-EE displayed hepatoprotective activity in a mouse model of hepatitis induced with LPS/D-galactosamine (D-GalN) through decreasing the serum levels of alanine aminotransferase and suppressing the activation of JNK and IRAK1. Therefore, our results strongly suggest that Dt-EE could be a candidate anti-inflammatory herbal medicine with IRAK1/AP-1 inhibitory and hepatoprotective properties.  相似文献   
58.
The present study was structured to investigate the anti-inflammatory potential of the extracts, fractions and compounds isolated from Carissa carandas (L.) roots. Bioassay guided fractionation of methanol extract based on inhibitory potential towards proinflammatory mediators (TNF-α, IL-1β and nitric oxide (NO)) led to the identification of stigmasterol (1), lupeol (2), oleanolic acid (3), carissone (4) and scopoletin (5) as potential anti-inflammatory agents. Carissone (4) (IC50 = 20.1 ± 2.69 μg/mL) and scopoletin (5) (IC50 = 24.6 ± 1.36 μg/mL) exhibited significant inhibition of NO production comparable to specific NO inhibitor (L-NAME; IC50 = 19.82 ± 1.64 μg/mL) without affecting the cell viability. Also, 4 and 5 at a concentration of 30 μM were found to inhibit 41.88–53.44% of TNF-α and IL-1β. To the best of our knowledge, this is the first report displaying the anti-inflammatory effects of C. carandas (L.) roots, partially mediated by inhibition of TNF-α, IL-1β and NO.  相似文献   
59.
Macrophages constitute a major part of natural tumor defense by their capacity to destroy selectively a broad range of tumor types upon specific activation. In the last couple of years, these cells have also been implicated as effector cells in the destruction of tumors by photodynamic therapy. In the present work, the potential role of macrophage-mediated tumor cytotoxicity after photodynamic treatment in vitro has been investigated with respect to photodynamic activation of macrophages for tumoricidal effector functions. Our data show that photodynamic treatment of highly pure murine bone-marrow-derived macrophages with the hematoporphyrin derivative Photosan-3 does not result in activation of these cells for cytotoxicity against YAC-1 tumor cells or secretion of tumor necrosis factor and nitric oxide, irrespective of co-stimulation with interferon-γ, a potent priming agent for macrophage antitumoral activity. On the contrary, treatment with higher photosensitizer doses is found to reduce markedly the viability of the macrophage effector cells. Thus, these results do not lend any support to the hypothesis of direct macrophage activation by photodynamic treatment. However, macrophages are found to be activated for tumoricidal effector functions indirectly by photodynamically killed tumor cells, in a way reminiscent of phagocytosis-inducing stimuli. It is thus suggested that recognition and phagocytosis of photodynamically destroyed tumor cells constitutes the major signal for local activation of macrophages in photodynamically treated tumor tissues, which may be crucial for final, specific eradication by the immune system of tumor cells surviving photodynamic treatment.  相似文献   
60.
Biocompatible hyaluronic acid (HA, hyaluronan) gel implants have altered the therapeutic landscape of surgery and medicine, fostering an array of innovative products that include viscosurgical aids, synovial supplements, and drug-eluting nanomaterials. However, it is perhaps the explosive growth in the cosmetic applications of injectable dermal fillers that has captured the brightest spotlight, emerging as the dominant modality in plastic surgery and aesthetic medicine. The popularity surge with which injectable HA fillers have risen to in vogue status has also brought a concomitant increase in the incidence of once-rare iatrogenic vaso-occlusive injuries ranging from disfiguring facial skin necrosis to disabling neuro-ophthalmological sequelae. As our understanding of the pathophysiology of these injuries has evolved, supplemented by more than a century of astute observations, the formulation of novel therapeutic and preventative strategies has permitted the amelioration of this burdensome complication. In this special issue article, we review the relevant mechanisms underlying HA filler-induced vascular occlusion (FIVO), with particular emphasis on the rheo-mechanical aspects of vascular blockade; the thromboembolic potential of HA mixtures; and the tissue-specific ischemic susceptibility of microvascular networks, which leads to underperfusion, hypoxia, and ultimate injury. In addition, recent therapeutic advances and novel considerations on the prevention and management of muco-cutaneous and neuro-ophthalmological complications are examined.  相似文献   
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