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Gecko phylogeography in the Western Indian Ocean region: the oldest clade of Ebenavia inunguis lives on the youngest island 下载免费PDF全文
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Cindy L K Lam 《BMJ (Clinical research ed.)》2001,323(7327):1458-1459
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Weng Shaoting Zhao Yitian Yu Changhong Wang Xiaofan Xiao Xuehan Han Liqiang Zhang Kunpeng Wang Jiang Yang Guoyu 《Biotechnology letters》2021,43(11):2111-2129
Biotechnology Letters - An ideal rAAV gene editing system not only effectively edits genes at specific site, but also prevents the spread of the virus from occurring off-target or carcinogenic... 相似文献
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Leo Lap-Yan Wong Ian Pak-Yan Lam Tracy Yuk-Nar Wong Wai-Lung Lai Heong-Fai Liu Lam-Lung Yeung Yick-Pang Ching 《PloS one》2013,8(7)
Hepatocellular carcinoma (HCC) is one of the major malignancies worldwide and is associated with poor prognosis due to the high incidences of metastasis and tumor recurrence. Our previous study showed that overexpression of p21-activated protein kinase 1 (PAK1) is frequently observed in HCC and is associated with a more aggressive tumor behavior, suggesting that PAK1 is a potential therapeutic target in HCC. In the current study, an allosteric small molecule PAK1 inhibitor, IPA-3, was evaluated for the potential in suppressing hepatocarcinogenesis. Consistent with other reports, inhibition of PAK1 activity was observed in several human HCC cell lines treated with various dosages of IPA-3. Using cell proliferation, colony formation and BrdU incorporation assays, we demonstrated that IPA-3 treatment significantly inhibited the growth of HCC cells. The mechanisms through which IPA-3 treatment suppresses HCC cell growth are enhancement of apoptosis and blockage of activation of NF-κB. Furthermore, our data suggested that IPA-3 not only inhibits the HCC cell growth, but also suppresses the metastatic potential of HCC cells. Nude mouse xenograft assay demonstrated that IPA-3 treatment significantly reduced the tumor growth rate and decreased tumor volume, indicating that IPA-3 can suppress the in vivo tumor growth of HCC cells. Taken together, our demonstration of the potential preclinical efficacy of IPA-3 in HCC provides the rationale for cancer therapy. 相似文献
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Lam , S. L. and A. C. Leopold . (Purdue U., Lafayette, Indiana.) Reversion from flowering to the vegetative state in Xanthium. Amer. Jour. Bot. 47(4): 256—259. Illus. 1960.–Plants of Xanthium pensylvanicum Wallr. which had been induced with short photoperiods were caused to revert to the vegetative state either by decapitation or by pinching and subsequent partial de-budding. The ability of induced plants to revert varies with the intensity of the inductive stimulus, and with the extent to which the plant is cut back. Four successive decapitation treatments caused complete reversion of almost all plants which had been given 7 inductive cycles. Reversion can be obtained after 3 inductive cycles even when all of the induced leaves remain on the plant. It is suggested that under the conditions of these experiments the synthesis of the flowering stimulus is stopped or the stimulus is immobilized in the leaves and made ineffective. 相似文献
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Purification of smooth-muscle myosin free of calmodulin and myosin light-chain kinase. Susceptibility to oxidation. 下载免费PDF全文
Smooth-muscle myosin purified as described by Persechini & Hartshorne [(1983) Biochemistry 22, 470-476] contains trace amounts of calmodulin and myosin light-chain kinase, which can be removed by Ca2+-dependent hydrophobic-interaction chromatography followed by calmodulin-Sepharose affinity chromatography. The resultant column-purified myosin exhibits properties similar to those of the non-purified myosin, e.g. actin activation of the Mg2+-ATPase requires Ca2+/calmodulin-dependent phosphorylation of the two 20 kDa light chains. However, unlike the non-purified myosin, the column-purified myosin undergoes a time-dependent transition to a form which no longer requires phosphorylation for actin activation of the myosin Mg2+-ATPase. This transition is identified as a time-dependent change in conformation of the column-purified myosin from a 10 S to 6 S form and is caused by slow oxidation of the column-purified myosin, since it could be prevented by storage under N2 and reversed by 5 mM-dithiothreitol. 相似文献
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T.‐H. Yen Y. Chen J.‐F. Fu C.‐H. Weng Y.‐C. Tian C.‐C. Hung J.‐L. Lin C.‐W. Yang 《Cell proliferation》2010,43(3):287-296
Objectives: Myofibroblasts are a vital component of stroma of many malignant neoplasms, but it is not yet established whether stromal myofibroblasts also exist in benign tumours such as oncocytoma of the kidney. Materials and methods: Histomorphological and immunohistochemical analysis of 16 renal oncocytomas diagnosed at Chang Gung Memorial Hospital, Taiwan, has been performed. Results: Renal oncocytomas were composed of oncocytes, large cells with granular eosinophilic cytoplasm, arranged mostly in sheets, in tubulocystic or combined pattern. Few oncocytes appeared to be undergoing proliferation or apoptosis. MIB‐1 and active caspase 3 indices were low, but higher in tumour than in surrounding non‐tumour parenchyma (MIB‐1: 0.93 ± 0.09 versus 0.46 ± 0.07, P < 0.001 and active caspase 3: 0.76 ± 0.08 versus 0.41 ± 0.09, P < 0.001). Wnt/β‐catenin signalling was not implicated in this neoplasm, as there was no loss of E‐cadherin membranous localization or expression of intranuclear β‐catenin in the cells. Clumps of oncocytes were stained with periodic acid Schiff and had collagen I‐, collagen III‐ and fibronectin‐positive, but desmin‐ and human caldesmon‐negative stromas. Importantly, α‐smooth muscle actin (SMA)‐immunostaining established the myofibroblastic nature of many of the stromal cells. Some of the myofibroblasts were also positive for MIB‐1, indicating a proliferative role for them in the stroma. Conclusions: Renal oncocytomas were composed of two independent compartments: benign oncocytes and pronounced fibrotic stroma, which consisted of proliferating myofibroblasts (SMA‐ and MIB‐1‐positive) which were associated with excessive deposition of extracellular matrix (periodic acid Schiff‐component, collagen I‐, collagen III‐ and fibronectin‐positive, and desmin‐ and human caldesmon‐negative). 相似文献