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<正>Dear Editor,Shortly after initiating the"Physical Anthropological Research on Han Chinese"research project,we applied uniform sampling methods as well as methods and instruments of measurement to obtain a complete set of measurements of physical anthropological indicators among Han populations across China.Among these measurements,body stature was a key indicator.Currently,there should be reliable  相似文献   
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【目的】根结线虫危害严重,难防难控,前期研究发现一株深海来源的独岛枝芽胞杆菌(Virgibacillus dokdonensis) MCCC 1A00493对南方根结线虫具有良好的体外拮抗效果,本研究分离鉴定菌株发酵液中杀线虫活性物质,对其作用线虫的多种模式进行研究,为菌株有效控制植物病原线虫的应用奠定理论基础。【方法】采用硅胶柱层析和半制备高效液相色谱对独岛枝芽胞杆菌发酵上清液中的杀线虫活性物质进行分离纯化,采用液相色谱质谱联用、核磁共振对纯化物进行结构鉴定;并对其趋避、诱杀、熏杀和卵孵化抑制活性进行检测。【结果】结构鉴定确定独岛枝芽胞杆菌MCCC 1A00493发酵液中分离的杀线虫活性物质为4-乙烯基苯酚。4-乙烯基苯酚对线虫具有触杀、熏杀、卵孵化抑制和高浓度驱避低浓度引诱活性,15μg/mL 4-乙烯基苯酚72 h触杀线虫校正死亡率为71.23%±9.06%;20 mg/mL 4-乙烯基苯酚24 h熏杀线虫死亡率达100%;100μg/mL4-乙烯基苯酚作用线虫卵10d后,卵孵化抑制率达66.2%;在琼脂平板上,10mg/mL的4-乙烯基苯酚对线虫有驱避作用,1 mg/mL的4-...  相似文献   
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E74-like factor 5 (Elf5) has been associated with tumor suppression in breast cancer. However, its role in urothelial cancer (UC) is completely unknown. Immunohistochemistry (IHC) and methylation specific PCR (MSP) were done to detect Elf5 expression level and its promoter methylation. Results revealed that low expression of Elf5 on protein and mRNA levels were associated with tumor progression, early relapse and poor survival. In vitro, down-regulation of Elf5 can increase epithelial-mesenchymal transition (EMT). Aberrant Elf5 methylation was identified as major mechanism for Elf5 gene silence. Accordingly, restoration of Elf5 by infection or demethylating treatment effectively reversed EMT processes. In conclusion, we identified Elf5 as a novel biomarker of UC on several biological levels and established a causative link between Elf5 and EMT in UC.  相似文献   
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Patients with hyperglycemia tend to be susceptible to Coronavirus disease 2019 (COVID-19). However, the association of HbA1c level with outcome of COVID-19 patients was unclear. We performed a retrospective study of 2880 cases of COVID-19 admitted in Tongji Hospital, Wuhan, China, among which 922 had detected the HbA1c levels. We found that COVID-19 patients with either lower levels of HbAlc (3%-4.9%) or higher levels of HbAlc (≥6%) were associated with elevated all-cause mortality. Meanwhile, we observed that HbAlc levels were highly correlated with haemoglobin (Hb) and total cholesterol (TC) (P < .0001), moderately correlated with albumin (ALB) and high-sensitive C reaction protein (hs-CRP) (0.0001 < P<.001), and relatively low correlated with low-density lipoprotein cholesterol (LDL-C) (.001 < P<.01). These associated cofactors might together contribute to the clinical outcome of COVID-19 patients. Furthermore, the mortality was higher in COVID-19 patients with newly diagnosed diabetes mellitus (DM) compared with COVID-19 patients with history of DM. Moreover, in patients with history of DM, the mortality was decreased in patients treated with anti-hyperglycaemic drugs. In summary, our data showed that the in-hospital mortality was increased in COVID-19 patients with lower or higher levels of HbAlc. Meanwhile, initiation of appropriate anti-hyperglycaemic treatment might improve the clinical outcome in COVID-19 patients.  相似文献   
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WANG  Jun  ZHANG  LiXin  LIANG  HouGuo 《Photosynthetica》1998,34(1):141-145
A peptide ranging from residues 229 to 240 (ENESANEGYRFG) of D1 protein was synthesized by stepwise solid-phase method. Resolution enhancement techniques were combined with band curve-fitting procedures to quantitate the FTIR spectra in the amide I' region (1700-1600 cm-1). FTIR analysis showed that DCMU induced drastic structural modification with a relative decrease of the unordered structure and turns, and a substantial increase of α-helix, which indicated that a much more compact structure was formed when DCMU was applied. The results may reflect molecular information for the protective effect of DCMU against photoinhibition.  相似文献   
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