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91.
NTRK1 gene fusions, the targets of multikinase inhibitors, are promising therapeutic targets for colorectal cancer (CRC). However, screening methods for detecting NTRK1 gene fusions in CRC tissues have not been reported. In this study, we investigated the potential use of immunohistochemistry (IHC) for detecting NTRK1 gene fusions. We performed and compared IHC with fluorescence in situ hybridization (FISH) in 80 CRC patients. TrkA immunostaining was observed to be both membranous and cytoplasmic and was scored semiquantitatively using staining intensity and proportions. The tumors were observed to be NTRK1 gene fusion-positive when ≥20 out of 100 nuclei in FISH. A significant correlation between the IHC and FISH results for determination of the NTRK1 gene fusions was observed. We measured the cytoplasmic TrkA expression, which showed an area under the receiver operating characteristic (ROC) curve of 0.926 (range: 0.864-0.987, 95% CI, P = .001). By choosing 4.5 (sum of the intensity and proportion scores of cytoplasmic TrkA expression) as the cut-off value for the positive and negative NTRK1 gene fusion groups, the sensitivity and specificity for predicting lymph node metastasis were 100 and 83.8%, respectively (P = .001). Specifically, high cytoplasmic TrkA expression (sum of intensity and proportion scores >4) was associated with the presence of NTRK1 gene fusions (P < .0001, r = 0.528). Taken together, our data showed that IHC for TrkA can be used as an efficient screening method for detecting NTRK1 gene fusions in CRC.  相似文献   
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ABSTRACT. The infraciliatures of three Chesapeake Bay species of Eutintinnus conforming in lorica morphology to E. angustatus, E. pectinis , and E. tenuis were compared following Protargol silver impregnation. The kinetome of these species had a number of shared attributes including: 1) a right and left field that were of similar length and kinetal spacing; 2) two, rarely three, long dorsal kineties composed of monokinetids; 3) a ventral kinety; and 4) the absence of a true posterior kinety. Nonetheless, the specific organization of infraciliary components varied considerably among species. For example, the organization of the ventral kinety and several kineties along the border of the left field was different in all three species. In addition, the dorsal kineties of E. angustatus differed positionally from those of E. pectinis and E. tenuis . Some divergence in oral infraciliature was also noted, with the arrangement of infundibular oral polykinetids in E. pectinis and E. tenuis being distinct from that of E. angustatus . The amount of variation in the infraciliature of Eutintinnus spp. was much greater than previously noted for congeneric species of tintinnines and supports the separation E. angustatus, E. pectinis , and E. tenuis at the generic or subgeneric level.  相似文献   
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Agrius convolvuli haemolymph ferritin was purified by KBr density gradient ultracentrifugation and anion exchange column chromatography. The 670 kDa ferritin was composed of two subunits of 26 kDa and 31 kDa. It was also shown that the protein had an isoelectric point (pI) of pH 7.4. The N‐terminal amino acid sequences of the two subunits were NH2‐DNXYQDVSLDXSQAXNXL (26 kDa subunit) and NH2‐TQXHVNPVNIQRDXVTMHXS (31 kDa subunit). The sequential analysis showed that they had high similarity to lepidopteran ferritin subunits, S‐ and G‐type, respectively. Using electron microscope, it was observed that the protein had a core whose size was about 7 nm. In the amino acid composition of the protein, Glu (13.22%), Asp (10.43%), Pro (9.69%), Leu (9.63%), Ala (9.55%) and Gly (8.49%) were in relatively high contents while Tyr (1.21%), His (2.58%) and Arg (3.10 %) were in low. It was shown that the amount of ferritin in A. convolvuli haemolymph was increased by injection of eight different heavy metal ions, FeCl3, HgCl2, CuSO4, ZnSO4, MnCl2, MgCl2, CrCl3 and CdCl2. Among the ions, Fe3+, Hg2+, Zn4+, Mn2+ and Cd.2+ significantly induced the amount of the protein.  相似文献   
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This study aimed to improve antioxidant effect and hepatoprotective effect of Inula britannica using fermentation. Epigallocatechin gallate (EGCG) in an I. britannica extract was found to be upregulated from 2.06 to 10.28 μg/mg during fermentation (p?<?0.001). After fermentation, DPPH radical-scavenging ABTS radical-scavenging, and superoxide anion-scavenging abilities increased to 92.65%, 694.25 μM Trolox/mL, and 86.38%, respectively, at 500 μg/mL (p?<?0.05). Cupric-ion-reducing capacity with formation of the Cu+-neocuproine complex increased by 5.88%, 6.38%, 3.24%, and 8.55% at 62.5 to 500 μg/mL. Ferric-ion-reducing capacity of the fermented extract increased by 20%, 7.16%, 3.85%, and 5.45% at each concentration (p?<?0.05). Unfermented extracts yielded cell viability of 91.42%, 90.59%, 88.38%, and 79.17%, whereas the fermented extract yielded 100.28%, 99.66%, 96.15%, and 89.90%, respectively, at each concentration in ethanol-damaged HepG2 cells (p?<?0.05). Additionally, the fermented extract decreased alanine transaminase activity from 117.2 to 61.7 U/mL in the ethanol-damaged HepG2 cell line (p?<?0.01). Overall, both antioxidant and hepatoprotective effect increased by fermentation in I. britannica extract. These properties are expected to lead to new antioxidant agents via production of EGCG by fermentation.

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崔哲慜  侯哲  高星 《人类学学报》2017,36(4):465-477
有柄尖刃器是朝鲜半岛旧石器时代晚期代表性狩猎工具,1964年在公州石壮里遗址中首次发现。原料多选择硅质页岩或与之相似的石料,多见于25,000-15,000 BP之间。之后随着石镞等复合工具的出现,有柄尖刃器逐渐被取代。本文观察和研究的305件有柄尖刃器来自朝鲜半岛33个遗址,通过分析其形态属性及工业类型,揭示有柄尖刃器的制作技法,探讨其与相邻地区的关系。在中国旧石器时代遗存中虽然也有关于有柄尖刃器的零星报道,但鲜有确凿者,望本文能为中国的相关研究提供有价值的参考资料。  相似文献   
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Hepatocellular carcinoma is a major health burden, and though various treatments through much research are available, difficulties in early diagnosis and drug resistance to chemotherapy-based treatments render several ineffective. Cancer stem cell model has been used to explain formation of heterogeneous cell population within tumor mass, which is one of the underlying causes of high recurrence rate and acquired chemoresistance, highlighting the importance of CSC identification and understanding the molecular mechanisms of CSC drivers. Extracellular CSC-markers such as CD133, CD90 and EpCAM have been used successfully in CSC isolation, but studies have indicated that increasingly complex combinations are required for accurate identification. Pseudogene-derived long non-coding RNAs are useful candidates as intracellular CSC markers - factors that regulate pluripotency and self-renewal – given their cancer-specific expression and versatile regulation across several levels. Here, we present the use of microarray data to identify stemness-associated factors in liver cancer, and selection of sole pseudogene-derived lncRNA ZNF204P for experimental validation. ZNF204P knockdown impairs cell proliferation and migration/invasion. As the cytosolic ZNF204P shares miRNA binding sites with OCT4 and SOX2, well-known drivers of pluripotency and self-renewal, we propose that ZNF204P promotes tumorigenesis through the miRNA-145-5p/OCT4, SOX2 axis.  相似文献   
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