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排序方式: 共有4516条查询结果,搜索用时 15 毫秒
941.
Xian Duan Bo Chen Yanan Cui Lin Zhou Chenkai Wu Zhulin Yang Yu Wen Xiongying Miao Qinglong Li Li Xiong Jun He 《Apoptosis : an international journal on programmed cell death》2018,23(11-12):587-606
Photodynamic therapy (PDT) is a procedure used in cancer therapy that has been shown to be useful for certain indications. Considerable evidence suggests that PDT might be superior to conventional modalities for some indications. In this report, we examine the relationship between PDT responsiveness and autophagy, which can exert a cytoprotective effect. Autophagy is an essential physiological process that maintains cellular homeostasis by degrading dysfunctional or impaired cellular components and organelles via a lysosome-based pathway. Autophagy, which includes macroautophagy and microautophagy, can be a factor that decreases or abolishes responses to various therapeutic protocols. We systematically discuss the mechanisms underlying cell-fate decisions elicited by PDT; analyse the principles of PDT-induced autophagy, macroautophagy and microautophagy; and present evidence to support the notion that autophagy is a critical mechanism in resistance to PDT. A combined strategy involving autophagy inhibitors may be able to further enhance PDT efficacy. Finally, we provide suggestions for future studies, note where our understanding of the relevant molecular regulators is deficient, and discuss the correlations among PDT-induced resistance and autophagy, especially microautophagy. 相似文献
942.
943.
David E. Jennings Juli R. Gould John D. Vandenberg Jian J. Duan Paula M. Shrewsbury 《PloS one》2013,8(12)
The emerald ash borer (EAB), Agrilus planipennis, is an invasive beetle that has killed millions of ash trees (Fraxinus spp.) since it was accidentally introduced to North America in the 1990s. Understanding how predators such as woodpeckers (Picidae) affect the population dynamics of EAB should enable us to more effectively manage the spread of this beetle, and toward this end we combined two experimental approaches to elucidate the relative importance of woodpecker predation on EAB populations. First, we examined wild populations of EAB in ash trees in New York, with each tree having a section screened to exclude woodpeckers. Second, we established experimental cohorts of EAB in ash trees in Maryland, and the cohorts on half of these trees were caged to exclude woodpeckers. The following spring these trees were debarked and the fates of the EAB larvae were determined. We found that trees from which woodpeckers were excluded consistently had significantly lower levels of predation, and that woodpecker predation comprised a greater source of mortality at sites with a more established wild infestation of EAB. Additionally, there was a considerable difference between New York and Maryland in the effect that woodpecker predation had on EAB population growth, suggesting that predation alone may not be a substantial factor in controlling EAB. In our experimental cohorts we also observed that trees from which woodpeckers were excluded had a significantly higher level of parasitism. The lower level of parasitism on EAB larvae found when exposed to woodpeckers has implications for EAB biological control, suggesting that it might be prudent to exclude woodpeckers from trees when attempting to establish parasitoid populations. Future studies may include utilizing EAB larval cohorts with a range of densities to explore the functional response of woodpeckers. 相似文献
944.
Dendrobium shixingense Z.‐L. Chen, S.‐J. Zeng et J. Duan sp. nov. (Orchidaceae), is described and illustrated from Guangdong, China; it is compared with its nearest allies, D. scoriarum, D. flexicaule and D. officinale. 相似文献
945.
The nematophagous fungi Paecilomyces lilacinus and Pochonia chlamydosporia have been extensively studied as biological control agents for plant-parasitic nematodes. This study describes the formulation of alginate pellets containing mycelia of these fungi and also describes the effect of storage conditions on shelf-life of the pellets. The shelf-lives of P. lilacinus and P. chlamydosporia, which were measured monthly for 6 months, were significantly improved at low temperatures and low water activity (a w) values (<0.33). Vacuum did not affect the viability of the formulated P. lilacinus but increased the viability of P. chlamydosporia. Carbon dioxide reduced the activity of P. lilacinus as compared to ambient air but increased the activity of P. chlamydosporia. Nitrogen, however, significantly improved the viability of both fungi. The optimal parameters of each factor for our formulation of P. lilacinus and P. chlamydosporia included a temperature range of 4 to ?20°C, a w=0.12, and a nitrogen-filled atmosphere. 相似文献
946.
947.
948.
Zhihua Zeng Wanming Zhou Lingxing Duan Jian Zhang Xiongbing Lu Liang Jin Yi Yu 《Journal of cellular physiology》2019,234(4):3887-3896
Increasing reports indicate that circular RNAs (circRNAs) are very important regulators in human diseases, including cancers. In bladder cancer (BC), several circRNAs have been reported to be involved in tumor progressions, such as circ-ITCH and circTCF25. However, the functions of most circRNAs in BC still remains largely unknown. In this study, we identified a novel circRNA termed as circ-VANGL1 by bioinformatics analysis. We found that circ-VANGL1 was highly expressed in BC tissues compared with adjacent normal tissues. Furthermore, we showed that circ-VANGL1 could serve as a prognostic marker for patients with BC. Through functional experiments, we found that circ-VANGL1 knockdown significantly suppressed BC cell proliferation, cell cycle, migration, and invasion in vitro. Besides, circ-VANGL1 silence inhibited BC cell propagation in vivo. Mechanistically, we identified circ-VANGL1 as a sponge of miR-605-3p which targeted VANGL1 in BC cells. Through repressing miR-605-3p availability, circ-VANGL1 contributes to VANGL1 expression, consequently leading to BC cell proliferation, migration, and invasion. Taken together, our study demonstrated circ-VANGL1/miR-605-3p/VANGL1 as a novel essential signaling pathway involved in BC progression. 相似文献
949.
Jin Liu Guohu Di Chu-Tse Wu Xianwen Hu Haifeng Duan 《Biochemical and biophysical research communications》2013,430(2):598-603
Carcinoembryonic antigen-related cell adhesion molecule 1 (CEACAM1) is a member of the immunoglobulin super family and has been observed to have two paradoxical functions: tumor suppression and the promotion of tumor invasion. In the present study, we discovered that CEACAM1 functions as an adhesion inhibitor and a migration promoter. The CEACAM1 transfected cells, either 293-CEACAM1 or LOVO/trans-CEACAM1, was proved to have lower adhesion rate. Furthermore, HT29/siRNA-CEACAM1 cells had a higher adhesion rate than HT29 cells. These results indicated that CEACAM1 was an inhibitor of cell-matrix adhesion. Additionally, 293-CEACAM1 LOVO/trans-CEACAM1 cells exhibited better motility in a trans-well migration assay. N-cadherin expression levels were positively correlated with CEACAM1 in 293-CEACAM1, LOVO/trans-CEACAM1 and HT29/siRNA-CEACAM1 cells. When blocked by a GC-4 antibody, the adhesive capacities of 293-CEACAM1 and LOVO/trans-CEACAM1 were recovered and the motilities of them were suppressed, which suggested that CEACAM1 functioned through N-cadherin. 相似文献
950.
Jian Jun Duan Ronald J. Prokopy Chih-Ming Yin Chris Bergweiler H. Oouchi 《Entomologia Experimentalis et Applicata》1995,77(1):17-21
Three-day old female apple maggot flies,Rhagoletis pomonella (Walsh), were topically exposed to different doses (0.1, 1, 10, and 100 μg per fly) of a juvenile hormone mimic, pyriproxyfen,
in the laboratory. Pyriproxyfen had little lethal effect on females except at the extremely high dose of 100 μg. It also had
no significant effect on egg viability of treated females. A non-lethal dose of 1 μg per fly did, however, enhance significantly
the fecundity (egg production) as well as the ovarian development (number of eggs in ovaries and length of egg folicles) of
treated flies. We conclude that pyriproxyfen could be a useful aid in exploring endocrine regulation of feeding and reproductive
physiology behavior inR. pomonella, about which current knowledge is scant. 相似文献