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31.
目的:研究血管内皮生长因子受体(VEGFR3)在舌癌淋巴转移中的作用,探索舌癌淋巴转移的机制。方法:采用免疫组化和RT-PCR技术,对90例不同分期的舌癌肿瘤进行VEGFR3的检测,与10例正常舌黏膜标本进行对照。采用SAS6.12软件进行单因素方差分析。结果:通过与正常组对照,Ⅰ、Ⅱ、Ⅲ期肿瘤中VEGFR3的表达无显著性差异(P>0.05),Ⅳ期肿瘤中VEGFR3的表达较正常对照组显著升高并具有显著性差异(P<0.05)。肿瘤各组间比较无显著性差异。转移组与非转移组之间也无显著性差异。结论:VEGFR3参与微淋巴管的生成,随着肿瘤的临床分期增高,其表达虽呈缓慢增高趋势,但尚不足以作为判定是否发生淋巴转移的客观指标。 相似文献
32.
目的 研究活血解毒方对缺氧/复氧(H/R)所致的心肌细胞凋亡的影响。方法 体外培养H9C2心肌细胞并分成正常对照组(Control组)、缺氧复氧组(H/R组)、H/R + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组,其中正常对照组给予DMEM培养基培养,缺氧复氧组给予缺氧4 h、复氧6 h处理,缺氧复氧 + 活血解毒中药组、LY294002组和活血解毒中药 + LY294002组分别给予活血解毒中药、LY294002、活血解毒中药配合LY294002预处理24 h,然后均给予缺氧4 h、复氧6 h处理。采用CCK8检测各组心肌细胞的存活率,流式细胞术检测各组细胞凋亡水平,电镜观察各组心肌细胞中线粒体、自噬体的变化,Western Blot检测各组细胞凋亡蛋白半胱氨酸天冬氨酸蛋白酶3(Caspase3)、半胱氨酸天冬氨酸蛋白水解酶3(Cleaved caspase3)、β-连环蛋白(β-Catenin)、p-p65、B淋巴细胞瘤-2(B-cell lymphoma-2,Bcl-2)蛋白的表达。结果 活血解毒方预处理显著增加H/R诱导的H9C2心肌细胞凋亡,降低凋亡相关蛋白Cleaved caspase3、β-Catenin、p-p65表达,增加Bcl-2表达。结论 活血解毒方可通过抑制细胞凋亡,降低缺氧/复氧所致的心肌细胞损伤,其作用机制可能与PI3K信号通路相关。 相似文献
33.
目的:了解和探讨云浮市社区、家庭、本院门诊、住院患者和陪同人员对居家护理服务的需求.方法:运用问卷调查的方法,访谈100例云浮市区60岁以上的老年人.结果:老年人对居家护理服务的认识不足,但对居家护理服务需求较多,希望得到社会支持:提供家居护理服务如健康指导、心理咨询、预防保健及治疗、康复锻炼等护理活动.结论:老年人对居家护理服务需求主要集中在健康指导、心理咨询、预防保健及治疗和康复锻炼等四大方面.但经济问题是制约老年人需求的重要因素,呼吁政府和社会关注老年居家护理,加大对老年居家护理服务的政策倾斜和资源投入. 相似文献
34.
目的:对一组症状,体征表现极相似于青光眼但非青光眼所致的颈椎病患者进行分析诊断,并作治疗探讨。方法:我院1993/2003-10间一组症状相似的颈椎病患者37例,分析其症状及体征特征,并与青光眼相鉴别。结果:通过此组患者症状体征分析,提醒相关医师掌握这些知识,对此组患者进行正确诊断和治疗。结论:该组患者是一组特殊类型的眼科患者,可暂称其为缺血性视疲劳。 相似文献
35.
Zhijun Yu Zhuo Chen Dongdong Qu Shoujiang Qu Hao Wang Fu Zhao Chaoqun Zhang Aihan Feng Daolun Chen 《Materials》2022,15(13)
3D printing (or more formally called additive manufacturing) has the potential to revolutionize the way objects are manufactured, ranging from critical applications such as aerospace components to medical devices, making the materials stronger, lighter and more durable than those manufactured via conventional methods. While the mechanical properties of Ti-6Al-4V parts manufactured with two major 3D printing techniques: selective laser melting (SLM) and electron beam melting (EBM), have been reported, it is unknown if the corrosion resistance of the 3D-printed parts is comparable to that of the alloy made with isothermal forging (ISF). The aim of this study was to identify the corrosion resistance and mechanisms of Ti-6Al-4V alloy manufactured by SLM, EBM and ISF via electrochemical corrosion tests in 3.5% NaCl solution, focusing on the effect of microstructures. It was observed that the equiaxed α + β microstructure in the ISF-manufactured Ti-6Al-4V alloy had a superior corrosion resistance to the acicular martensitic α′ + β and lamellar α + β microstructures of the 3D-printed samples via SLM and EBM, respectively. This was mainly due to the fact that (1) a higher amount of β phase was present in the ISF-manufactured sample, and (2) the fraction of phase interfaces was lower in the equiaxed α + β microstructure than in the acicular α′ + β and lamellar α + β microstructures, leading to fewer microgalvanic cells. The lower corrosion resistance of SLM-manufactured sample was also related to the higher strain energy and lower electrochemical potential induced by the presence of martensitic twins, resulting in faster anodic dissolution and higher corrosion rate. 相似文献
36.
Jian Zhai Jianwei Liu Zhigang Fu Shilei Bai Xiaowei Li Zengqiang Qu Yanfu Sun Ruiliang Ge Feng Xue 《Journal of gastrointestinal oncology.》2022,13(3):1278
BackgroundThere is lack of studies on sequential regorafenib after sorafenib and lenvatinib treatment failure in patients with unresectable hepatocellular carcinoma (HCC). This study was to explore the safety and prognosis of sequential regorafenib after sorafenib and lenvatinib failure in HCC patients.MethodsThis study was a retrospective, real-world study that included 50 HCC patients who received sequential regrafinib after sorafenib and lenvatinib failure. The safety and prognosis of two groups were compared.ResultsThe incidence of all grade and III/IV adverse events were 68% and 24%. According to Response Evaluation Criteria in Solid Tumours (RECIST) 1.1 and modified (m) RECIST standards, the objective response rates (ORRs) after receiving regorafenib were 14.0% and 22.0%, respectively. The disease control rates (DCRs) were 62.0% and 60.0%, respectively. Based on different first-line targeted drugs, 50 patients were divided into sorafenib (n=22) and lenvatinib group (n=28). There was no differences between two groups except age and bilirubin. And there was no differences in other treatments before or after regorafenib. The baseline between two groups was basically same and had good comparability. There was no difference in incidence of all grade and III/IV adverse events, ORR and DCR between two groups (P>0.05). On long-term prognosis, total overall survival (TOS) in sorafenib and lenvatinib group were 23.0 (95% CI: 15.1–30.9) vs. 29.7 (95% CI: 21.4–38.1) months. The difference was statistically significant (P=0.041). Besides, regorafenib overall survival (ROS) in sorafenib and lenvatinib group were 11.7 (95% CI: 7.1–16.3) vs. 15.9 (95% CI: 8.3–23.5) months. The difference was statistically significant ( P=0.045). The regorafenib progression-free survival (RPFS) was 5.6 (95% CI: 1.9–9.2) vs. 8.0 (95% CI: 5.1–10.9) months in sorafenib and lenvatinib group, respectively, and difference was not statistically significant (P=0.380).ConclusionsRegorafenib is an effective drug for second-line treatment of HCC, with fewer severe adverse events, ORR and DCR was 14–22% and 62–60%, respectively. Both TOS and ROS in lenvatinib group were better than those in sorafenib group. For HCC patients whose first-line targeted drug is lenvatinib, it is safe and effective to accept regorafenib after disease progresses. 相似文献
37.
Context 2a,-3a,-24-Trihydroxyurs-12-en-28-oic acid (TEO, a corosolic acid analogue) is a triterpenoid saponin isolated from Actinidia valvata Dunn (Actinidiaceae), a well-known traditional Chinese medicine.Objective This study investigated the anti-proliferation and inducing apoptosis effects of TEO in three human hepatocellular carcinoma (HCC) cell lines.Materials and methods Cytotoxic activity of TEO was determined by the MTT assay at various concentrations from 2.5 to 40?μg/mL in BEL-7402, BEL-7404 and SMMC-7721 cell lines. Cell morphology was assessed by acridine orange/ethidium bromide and 4′-6-diamidino-2-phenylindole dihydrochloride staining and fluorescence microscopy. Cell-cycle distribution and DNA damage were determined by flow cytometry and comet assay. Mitochondrial dysfunction was assessed by JC-1 staining and transmission electron microscopy. Apoptosis changes were explored by Western blot, TNF-α and caspase-3, -8, -9 assays.Results TEO exhibited inhibition effects on BEL-7402, BEL-7404 and SMMC-7721 cells treated for 24?h, the IC50 values were 34.6, 30.8 and 30.5?μg/mL, respectively. TEO (40?μg/mL)-treated three cell lines increased by more than 21% in the G1 phase and presented the morphological change and DNA damage. TEO also declined the mitochondrial membrane potential and altered mitochondrial ultra-structure. Furthermore, caspase-3, caspase-8, caspase-9 and TNF-α were also activated. Mechanism investigation showed that TEO could decrease anti-apoptotic Bcl-2 protein expression, increase proapoptotic Bax and Bid proteins expressions and increase Bax/Bcl-2 ratio.Conclusion Our results demonstrate for the first time that TEO inhibited growth of HCC cell lines and induced G1 phase arrest. Moreover, proapoptotic effects of TEO were mediated through the activation of TNF-α, caspases and mitochondrial pathway. 相似文献
38.
Previous studies have revealed that phonological processing of Chinese characters elicited activation in the left prefrontal cortex, bilateral parietal cortex, and occipitotemporal regions. However, it is controversial what role the left middle frontal gyrus plays in Chinese character reading, and whether the core regions (e.g., the left superior temporal gyrus and supramarginal gyrus) for phonological processing of alphabetic languages are also involved in Chinese character reading. To address these questions, the present study used both univariate and multivariate analysis (i.e., representational similarity analysis, RSA) to explore neural representations of phonological information during Chinese character reading. Participants were scanned while performing a reading aloud task. Univariate activation analysis revealed a widely distributed network for word reading, including the bilateral inferior frontal gyrus, middle frontal gyrus, lateral temporal cortex, and occipitotemporal cortex. More importantly, RSA showed that the left prefrontal (i.e., the left middle frontal gyrus and left inferior frontal gyrus) and bilateral occipitotemporal areas (i.e., the left inferior and middle temporal gyrus and bilateral fusiform gyrus) represented phonological information of Chinese characters. These results confirmed the importance of the left middle frontal gyrus and regions in ventral pathway in representing phonological information of Chinese characters. 相似文献
39.
40.
目的:研究慢性鼻-鼻窦炎(CRS)筛窦骨质病理形态学改变的相关因素。方法:CRS患者180例,其中Ⅰ、Ⅱ和Ⅲ型各60例,鼻内镜手术中取带有筛窦黏膜的筛骨标本送病理苏木精-伊红染色,对其病理形态学改变严重程度进行分级。统计不同临床分型其病理分级的例数及所占比率。分析筛窦骨质病理改变严重程度与筛窦黏膜病理改变程度、筛窦CT分型、病程长短及是否有手术史的关系。结果:所有患者筛窦骨质发生不同程度的病理形态学改变。病理分级:Ⅰ级5例(2.78%),Ⅱ级38例(21.11%),Ⅲ级71例(39.44%),Ⅳ级66例(36.67%)。Ⅰ、Ⅱ和Ⅲ型的筛骨病理分级结果:Ⅰ型,Ⅰ级5例(8.33%),Ⅱ级33例(55.00%),Ⅲ级15例(25.00%),Ⅳ级7例(11.67%);Ⅱ型,Ⅱ级5例(8.33%),Ⅲ级37例(61.67%),Ⅳ级18例(30.00%);Ⅲ型,Ⅲ级19例(31.67%),Ⅳ级41例(68.33%)。180例CRS患者不同临床分型、筛窦黏膜病理改变严重程度、不同筛窦CT分型、病程长短及是否有手术史与筛窦骨质病理分级均差异有统计学意义(均P<0.01)。结论:CRS筛窦骨质发生不同程度的病理形态学改变,其... 相似文献