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91.
Fibroblast growth factor receptor‐like 1 (FGFRL1), a member of the FGFR family, has been demonstrated to play important roles in various cancers. However, the role of FGFRL1 in small‐cell lung cancer (SCLC) remains unclear. Our study aimed to investigate the role of FGFRL1 in chemoresistance of SCLC and elucidate the possible molecular mechanism. We found that FGFRL1 levels are significantly up‐regulated in multidrug‐resistant SCLC cells (H69AR and H446DDP) compared with the sensitive parental cells (H69 and H446). In addition, clinical samples showed that FGFRL1 was overexpressed in SCLC tissues, and high FGFRL1 expression was associated with the clinical stage, chemotherapy response and survival time of SCLC patients. Knockdown of FGFRL1 in chemoresistant SCLC cells increased chemosensitivity by increasing cell apoptosis and cell cycle arrest, whereas overexpression of FGFRL1 in chemosensitive SCLC cells produced the opposite results. Mechanistic investigations showed that FGFRL1 interacts with ENO1, and FGFRL1 was found to regulate the expression of ENO1 and its downstream signalling pathway (the PI3K/Akt pathway) in SCLC cells. In brief, our study demonstrated that FGFRL1 modulates chemoresistance of SCLC by regulating the ENO1‐PI3K/Akt pathway. FGFRL1 may be a predictor and a potential therapeutic target for chemoresistance in SCLC.  相似文献   
92.
A water‐soluble polysaccharide (APP‐AW) was isolated from Agrimonia pilosa and prepared to three sulphated derivatives (S1, S2 and S3). The results showed that pre‐treatment with APP‐AW, S1, S2 and S3 each at the concentration of 50 μg/mL for 48 hours was able to prevent cytotoxicity induced by 1 μmol/L dexamethasone (Dex) in MC3T3‐E1 cells via inhibition of apoptosis, which is in line with the findings in flow cytometry analysis. Meanwhile, the decreased ALP activity, collagen content, mineralization, BMP2, Runx2, OSX and OCN protein expression in DEX‐treated MC3T3‐E1 cells were reversed by the addition of APP‐AW, S1, S2 and S3. Moreover, APP‐AW, S1, S2 and S3 rescued DEX‐induced increase of Bax, cytochrome c and caspase‐3 and decrease of Bcl‐2, Wnt3, β‐catenin and c‐Myc protein expression in MC3T3‐E1 cells. Our findings suggest that pre‐treatment with APP‐AW, S1, S2 and S3 could significantly protect MC3T3‐E1 cells against Dex‐induced cell injury via inhibiting apoptosis and activating Wnt/β‐Catenin signalling pathway, thus application of these polysaccharides may be a promising alternative strategy for steroid‐induced avascular necrosis of the femoral head (SANFH) therapy.  相似文献   
93.
Suboptimal health status (SHS), a physical state between health and disease, is a subclinical and reversible stage of chronic disease. Previous studies have shown alterations in the intestinal microbiota in patients with some chronic diseases. This study aimed to investigate the association between SHS and intestinal microbiota in a case‐control study with 50 SHS individuals and 50 matched healthy controls. Intestinal microbiota was analysed by MiSeq 250PE. Alpha diversity of intestinal microbiota in SHS individuals was higher compared with that of healthy controls (Simpson index, W = 2238, P = .048). Beta diversity was different between SHS and healthy controls (P = .018). At the phylum level, the relative abundance of Verrucomicrobia was higher in the SHS group than that in the controls (W = 2201, P = .049). Compared with that of the control group, nine genera were significantly higher and five genera were lower in abundance in the SHS group (all P < .05). The intestinal microbiota, analysed by a random forest model, was able to distinguish individuals with SHS from the controls, with an area under the curve of 0.79 (95% confidence interval: 0.77‐0.81). We demonstrated that the alteration of intestinal microbiota occurs with SHS, an early stage of disease, which might shed light on the importance of intestinal microbiota in the primary prevention of noncommunicable chronic diseases.  相似文献   
94.
Energy generation and consumption have always been an important component of social development. Interests in this field are beginning to shift to indoor photovoltaics (IPV) which can serve as power sources under low light conditions to meet the energy needs of rapidly growing fields, such as intelligence gathering and information processing which usually operate via the Internet‐of‐things (IoT). Since the power requirements for this purpose continue to decrease, IPV systems under low light may facilitate the realization of self‐powered high‐tech electronic devices connected through the IoT. This review discusses and compares the characteristics of different types of IPV devices such as those based on silicon, dye, III‐V semiconductors, organic compounds, and halide perovskites. Among them, specific attention is paid to perovskite photovoltaics which may potentially become a high performing IPV system due to the fascinating photophysics of the halide perovskite active layer. The limitations of such indoor application as they relate to the toxicity, stability, and electronic structure of halide perovskites are also discussed. Finally, strategies which could produce highly functional, nontoxic, and stable perovskite photovoltaics devices for indoor applications are proposed.  相似文献   
95.
The photoelectrochemical performance of the WO3 photoanode is limited by the severe charge recombination in the bulk phase and at the WO3/electrolyte interface. Herein, In2S3 nanosheets are integrated onto the surface of the WO3 nanowall array photoanode, followed by a facile polyvinylpyrrolidone (PVP) solution treatment. The PVP treatment results in sulfur vacancies and a gradient oxygen doping into In2S3 from surface to interior, which induces the formation of a gradient energy band distribution. The gradient band structured In2S3 and type II band alignment at the WO3/In2S3 interface simultaneously create a channel that favors photogenerated electrons to migrate from the surface to the conductive substrate, thereby suppressing bulk carrier recombination. Meanwhile, the sulfur vacancies and oxygen doping contribute to increased charge carrier concentration, prolonged carrier lifetime, more active sites, and small interfacial transfer impedance. As a consequence, the PVP treated WO3/In2S3 heterostructure photoanode exhibits a significantly enhanced photocurrent of 1.61 mA cm?2 at 1.23 V versus reversible hydrogen electrode (RHE) and negative onset potential of 0.02 V versus RHE.  相似文献   
96.
海岸带植物叶片的化学计量学特征及其影响因素可以为改善海岸带的生态环境提供理论依据。选取海南岛沿岸12个市(县)海岸带木麻黄防护林的木麻黄和周边沙滩上的藤本植物厚藤为研究对象,通过测定木麻黄与厚藤叶片中的碳(C)、氮(N)和磷(P)含量,分析两种植物叶片C、N和P的化学计量学特征及其差异,探究不同环境因子对两种植物叶片C、N、P含量、C:N、C:P和N:P的影响,以期寻找影响海岸带植被生长的主要限制因素。结果表明:海南岛木麻黄叶片C、N和P的平均含量分别是399.06±20.29、12.56±1.04、1.04±0.35 g·kg-1,C:N、C:P和N:P分别为32.04±2.82、420.65±121.27和12.92±3.21;厚藤叶片C、N和P的平均含量分别是364.31±30.20、12.84±1.96和2.06±0.64 g·kg-1,C:N、C:P和N:P分别为29.13±4.95、185.85±63.14和6.47±2.12。相关性分析结果表明:木麻黄叶片的N含量与年平均气温和年平均降水量呈显著正相关关系,P含量与年平均降水量呈极显著正相关关系,C:P和N:P与年平均降水量呈显著负相关关系;厚藤叶片C含量与年平均气温呈显著正相关,C:N与年平均降水量呈显著负相关。木麻黄叶片的N含量与10~20 cm土层的SOC呈显著负相关关系,C:N与10~20 cm土层的SOC呈显著正相关,C:P与0~10 cm土层的C:N呈显著正相关关系;厚藤叶片的C含量与10~20 cm土层的SOC呈显著负相关关系,P含量与0~10 cm土层的TN含量,N:P和10~20 cm的SOC含量呈正相关关系,C:N与0~10 cm土层的C:N呈显著正相关关系,C:P与0~10 cm的TN含量呈显著负相关关系而与0~10 cm土层的C:N呈极显著正相关关系,N:P与0~10 cm土层的TN含量呈显著负相关关系。研究结果表明海南岛海岸带植被叶片的碳氮含量较低,N可能是影响该区域植物生长的主要因子,同时,植被生长受到年平均气温、年平均降水量的共同影响,受土壤养分含量影响低,环境因子对不同类型的植物的影响并不相同。  相似文献   
97.
目的:研究甲状腺结节良恶性的彩色多普勒超声特征及其诊断价值。方法:选取从2016年3月~2019年2月于我院接受手术治疗的甲状腺疾病患者300例作为研究对象,均予以彩超检查,比较甲状腺良恶性结节的超声特征(主要包括直径、钙化情况、边界、回声、血流状况)。以病理活检结果为金标准,分析彩超诊断甲状腺结节良恶性的敏感性、特异性以及准确度。对比甲状腺良恶性结节的血流分型情况以及各项血流动力学参数。结果:恶性结节超声特征直径≥2 cm、有钙化、边界模糊、无回声/低回声、血流丰富人数占比均高于良性结节(均P<0.05)。以手术病理组织活检结果作为金标准,彩色多普勒超声诊断甲状腺结节的敏感性、特异性以及准确度分别为97.73%、86.11%、96.33%。甲状腺良性结节血流分型为Ⅰ型、Ⅱ型人数占比高于恶性结节,而Ⅲ型、Ⅳ型人数占比低于恶性结节(均P<0.05)。甲状腺良性结节的收缩期峰值血流速度(PSV)、阻力指数(RI)均低于恶性结节,而舒张末期血流速度(EDV)高于恶性结节(均P<0.05)。结论:彩色多普勒超声对甲状腺结节良恶性的鉴别价值较高,且具有较高的敏感性、特异性以及准确度,可为甲状腺良恶性结节的早期诊断、临床治疗提供重要的参考依据。  相似文献   
98.
为了提高实验室人类免疫缺陷病毒(human immunodeficiency virus,HIV)抗体检测能力及对免疫蛋白印迹(Western blot,WB)实验结果的判断能力,对送检至北京市东城区艾滋病确证实验室的268份HIV抗体待确定样本进行确证实验及结果分析。按照试剂说明书和实验室标准作业程序(Standard Operation Procedure,SOP)操作对送检的全部样本进行WB确证实验;了解HIV筛查实验结果与确证实验结果的相关性,并分析不同送检机构、送检人群样本的检测结果差异以及不同试剂、不同检测方法的结果差异。结果显示在筛查出抗体待确定的268份样本中,确证阳性170份,阳性率63.43%;确证阴性51份,阴性率19.03%;不确定结果47份,占筛查有反应的17.54%。确证阳性病例来自监管场所、自愿咨询检测门诊(Voluntary Counseling and Test,VCT)和医疗机构,不同送检单位及不同人群的阳性样本率有显著统计学意义(P<0.01)。WB确证阳性样本带型以全条带和次全条带为主,且所有确证阳性标本均来自双试剂阳性样本。不同检测方法阳性样本率的差异有显著统计学意义(P<0.01),其中化学发光法的样本阳性率占46.27%,酶联免疫吸附实验(ELISA)占88.29%,胶体硒法占43.48%。本研究结果提示,对潜在HIV感染者,应扩大检测面,加强医疗机构检测,并提供一种以上方法的多次检测,以减少漏检的风险。  相似文献   
99.
目的:探讨开放性楔形胫骨高位截骨术(OWHTO)中采用不同目标力线对单间室膝关节骨性关节炎(KOA)疗效的影响。方法:回顾性分析本院收治的2016年9月~2018年9月采用OWHTO治疗单间室KOA患者41例的临床资料,根据不同目标力线分为固定力线组和个体化力线组,固定力线组19例患者采用统一调目标力线至Fujisawa点治疗,个体化力线组22例根据术中关节软骨Outerbridge分级、个体化调定目标力线治疗,对比两组术前及术后1.5个月、3个月、6个月、12个月的疼痛视觉模拟评分(VAS)及美国特种外科医院膝关节(HSS)评分变化,并对比术前和12个月时MRI及关节镜影像。结果:术后所有患者VAS评分、HSS评分均较术前改善(P0.05),其中个体化力线组术后1.5个月、3个月时VAS评分优于固定力线组,差异有统计学意义(P0.05)。MRI及关节镜显示两组患者均有不同程度软骨再生。结论:采用OWHTO治疗单间室KOA,根据患者不同软骨磨损情况制定个体化目标力线方案有利于患者早期疼痛的改善,但其长期功能的恢复及软骨再生与固定力线方案无明显差异。  相似文献   
100.
目的:探讨微小RNA-221/222(miR-221/222)对乳腺癌MDA-MB-231/阿霉素(DOX)细胞DOX耐药性的影响。方法:采用脂质体法转染miR-221/222抑制物(miR-221/222 inhibitor)至MDA-MB-231/DOX细胞内(Inhibitor组),同时设立空白对照组和转染无关序列的阴性对照组,采用实时荧光定量PCR (qRT-PCR)检测MDA-MB-231细胞株及MDA-MB-231/DOX细胞株的miR-221/222表达水平及转染效率;CCK-8法检测转染48 h后MDA-MB-231/DOX细胞对DOX药物敏感性的变化;流式细胞术(FCM)检测转染MDA-MB-231/DOX细胞的细胞凋亡率;蛋白免疫印迹实验(WB)检测转染后MDA-MB-231/DOX细胞内促凋亡蛋白p53上调凋亡调控因子(PUMA),Bcl2蛋白修饰因子(BMF)以及细胞周期蛋白激酶抑制因子p27(p27Kip1)的表达情况。结果:MDA-MB-231/DOX细胞中的miR-221/222表达水平高于亲本MDA-MB-231细胞(P0.05);MDA-MB-231/DOX细胞转染miR-221/222 inhibitor 96 h后,miR-221/222的表达水平低于空白对照组和阴性对照组(P0.05);与空白对照组相比,MDA-MB-231/DOX细胞转染miR-221/222 inhibitor 48h后,DOX继续处理48 h后,细胞的凋亡率明显升高,且细胞内的促凋亡蛋白PUMA,BMF以及p27Kip1的表达均增加(P0.05);DOX对inhibitor组耐药细胞的半数抑制浓度(IC50)显著低于空白对照组细胞及阴性对照组(P0.05)。结论:miR-221/222能够增加MDA-MB-231/DOX细胞对DOX的耐药性,这可能与下调促凋亡蛋白的表达有关;降低miR-221/222水平可诱导MDA-MB-231/DOX凋亡,并且上调促凋亡蛋白的表达,从而部分逆转MDA-MB-231/DOX对DOX的耐药性。  相似文献   
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