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91.
In this study, we investigated the ability of curcumin alone or in combination with GLUT1 siRNA to radiosensitize laryngeal carcinoma (LC) through the induction of autophagy. Protein levels in tumour tissues and LC cells were measured by immunohistochemistry and Western blotting. In vitro, cell proliferation, colony formation assays, cell death and autophagy were detected. A nude mouse xenograft model was established through the injection of Tu212 cells. We found that GLUT1 was highly expressed and negatively associated with autophagy-related proteins in LC and that curcumin suppressed radiation-mediated GLUT1 overexpression in Tu212 cells. Treatment with curcumin, GLUT1 siRNA, or the combination of the two promoted autophagy. Inhibition of autophagy using 6-amino-3-methypourine (3-MA) promoted apoptosis after irradiation or treatment of cells with curcumin and GLUT1 siRNA. 3-MA inhibited curcumin and GLUT1 siRNA-mediated non-apoptotic programmed cell death. The combination of curcumin, GLUT1 siRNA and 3-MA provided the strongest sensitization in vivo. We also found that autophagy induction after curcumin or GLUT1 siRNA treatment implicated in the AMP-activated protein kinase-mTOR-serine/threonine-protein kinase-Beclin1 signalling pathway. Irradiation primarily caused apoptosis, and when combined with curcumin and GLUT1 siRNA treatment, the increased radiosensitivity of LC occurred through the concurrent induction of apoptosis and autophagy.  相似文献   
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Cahara Ghauri from China with three species is reviewed here. Two of them, Cahara incisura sp. n. and Cahara nodula sp. n. are described here. Key to the three Chinese species, habitus photographs and illustrations of genitalia are also provided. All examined materials including the types of three species mentioned are deposited in the Institute of Entomology, Nankai University, Tianjin, China (NKUM).  相似文献   
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A cysticercus of a possibly undescribed species of Taenia which occurs commonly in Taiwan aborigines was used to establish an experimental infection in a human volunteer. Symptomatic effects attributed to the infection included diarrhoea, upper abdominal pain, and increase or loss of appetite over a four-month period. After an expelled proglottid was observed 122 days post-exposure, eggs and proglottids were found continuously until the patient was treated with anthelmintics. Antibody titres measured by enzyme-linked immunosorbent assay and levels of eosinophilia seemed to correlate with symptoms. Haematological analyses revealed an abnormal lipid metabolism during the entire symptomatic period.  相似文献   
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Mode of cell wall synthesis in gram-positive bacilli.   总被引:7,自引:5,他引:2       下载免费PDF全文
Ultrastructural experiments on plasmolyzed cells suggested that the information for the position and orderly synthesis of septa is not determined by the attachment of cell membrane to previously formed wall. These experiments, in conjunction with others on cells disrupted by the freeze-fracture technique, are most consistent with wall growth over the entire surface of the rods, with wall material gradually moving from a position next to the cell membrane to a position at the outer surface of the cell.  相似文献   
99.
Upon removal of the nucleus from rat hepatoma tissue culture cells, levels of the enzyme tyrosine aminotransferase no longer change in response to withdrawal of glucocorticoids. The rate of tyrosine aminotransferase degradation is drastically reduced in rat hepatoma tissue culture cytoplasts leading to stabilization of pre-existing levels of tyrosine aminotransferase. Moreover, the rate of synthesis of the enzyme in cytoplasts is very low near that observed in uninduced whole cells. These effects of enucleation occur very rapidly and appear to be specific for tyrosine aminotransferase and a small number of other unstable hepatoma proteins. A nuclear effect is thus directly involved in the control of tyrosine aminotransferase degradation and synthesis.  相似文献   
100.
The gene for the human mineralocorticoid receptor (MLR) was previously localized to chromosome 4. Here, we have localized this gene to 4q31.2 by in situ hybridization. This precise mapping of MLR will assist in the linkage analysis and genetic characterization of pseudohypoaldosteronism, an autosomal recessive disorder which likely results from a defect in the MLR gene.  相似文献   
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