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11.
目的 利用频域光学相干断层扫描深度增强(enhanced depth imaging spectral domain optical coherence tomography,EDI SD-OCT)观察糖尿病黄斑水肿(diabetic macular edema,DME)患者脉络膜厚度(choroidal thickness,CT)的变化及结构特点,探讨DME病变程度与CT的关系。方法 纳入2型糖尿病患者共123例204眼,其中69眼诊断为DME(DME组),135眼无黄斑水肿为对照组。DME眼依据OCT形态学特点进一步分为视网膜弥漫性增厚(diffuse retinal thickness,DRT)型(34眼)、黄斑囊样水肿(cystoid macular edema,CME)型(19眼)和浆液性视网膜脱离(serous retinal detachment,SRD)型(16眼),利用EDI-OCT分别测量黄斑中心凹下CT和以黄斑为中心上、下、鼻、颞500 μm、1000 μm、1500 μm、2000 μm处CT。结果 DME组黄斑中心凹下CT为(326.72±90.15)μm,对照组为(320.17±106.46)μm,两组之间无统计学差异,但黄斑中心凹下CT与视网膜厚度间具有明显正相关关系(r=0.270,P=0.025)。DME亚型CT分别为:DRT型(303.94±81.47)μm、CME型(304.42±73.98)μm和SRD型(401.63±88.80)μm,SRD型CT明显高于其他亚型(P<0.05),此外,SRD型的周边CT同样呈现均匀一致的增厚;鼻侧CT从500 μm至2000 μm呈距离敏感性降低(P<0.05),但SRD型鼻侧CT降低幅度明显变缓(P=0.195)。结论 SRD型黄斑水肿患者CT在中心凹下及周边部均显著增厚,CT与DME病变程度之间有一定相关性。  相似文献   
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Three‐dimensional (3D) printing technology, virtual reality, and augmented reality technology have been used to help surgeons to complete complex total hip arthroplasty, while their respective shortcomings limit their further application. With the development of technology, mixed reality (MR) technology has been applied to improve the success rate of complicated hip arthroplasty because of its unique advantages. We presented a case of a 59‐year‐old man with an intertrochanteric fracture in the left femur, who had received a prior left hip fusion. After admission to our hospital, a left total hip arthroplasty was performed on the patient using a combination of MR technology and 3D printing technology. Before surgery, 3D reconstruction of a certain bony landmark exposed in the surgical area was first performed. Then a veneer part was designed according to the bony landmark and connected to a reference registration landmark outside the body through a connecting rod. After that, the series of parts were made into a holistic reference registration instrument using 3D printing technology, and the patient's data for bone and surrounding tissue, along with digital 3D information of the reference registration instrument, were imported into the head‐mounted display (HMD). During the operation, the disinfected reference registration instrument was installed on the selected bony landmark, and then the automatic real‐time registration was realized by HMD through recognizing the registration landmark on the reference registration instrument, whereby the patient's virtual bone and other anatomical structures were quickly and accurately superimposed on the real body of the patient. To the best of our knowledge, this is the first report to use MR combined with 3D printing technology in total hip arthroplasty.  相似文献   
14.
The present study compared the level of occupational strain and work ability among Han, Hui, Uygur, Hui, and Kazakh teachers, and explored ethnic differences based on the associations of psychosocial factors at work, occupational strain, and work ability. A cross-sectional survey was conducted among 2,941 teachers in primary and secondary schools in Xinjiang Province, China. Psychosocial factors, occupational strain, and work ability were measured using the Occupation Stress Inventory—Revised Edition (OSI-R) and Work Ability Index. Han and Hui teachers experienced reduced work ability compared with Uygur and Kazakh teachers, and this finding was caused, in part, by exposure to psychosocial factors at work. The vocational and psychological strains caused by these factors play an important role in reduced work ability among all ethnic teacher groups. The findings indicate the importance of taking action to reduce occupational strain for promoting teachers' work ability in multiethnic workplaces.  相似文献   
15.
The acquisition of chemoresistance remains a major cause of cancer mortality due to the limited accessibility of targeted or immune therapies. However, given that severe alterations of molecular features during epithelial‐to‐mesenchymal transition (EMT) lead to acquired chemoresistance, emerging studies have focused on identifying targetable drivers associated with acquired chemoresistance. Particularly, AXL, a key receptor tyrosine kinase that confers resistance against targets and chemotherapeutics, is highly expressed in mesenchymal cancer cells. However, the underlying mechanism of AXL induction in mesenchymal cancer cells is poorly understood. Our study revealed that the YAP signature, which was highly enriched in mesenchymal‐type lung cancer, was closely correlated to AXL expression in 181 lung cancer cell lines. Moreover, using isogenic lung cancer cell pairs, we also found that doxorubicin treatment induced YAP nuclear translocation in mesenchymal‐type lung cancer cells to induce AXL expression. Additionally, the concurrent activation of TGFβ signaling coordinated YAP‐dependent AXL expression through SMAD4. These data suggest that crosstalk between YAP and the TGFβ/SMAD axis upon treatment with chemotherapeutics might be a promising target to improve chemosensitivity in mesenchymal‐type lung cancer.

Abbreviations

AUC
area under the curve
AXL
AXL receptor tyrosine kinase
BCL2
B‐cell lymphoma 2
CTD2
cancer target discovery and development
CTGF
connective tissue growth factor
DEG
differentially expressed genes
DOXO
doxorubicin
EMT
epithelial–mesenchymal transition
Eto
etoposide
FDA
Food and Drug Administration
ITGB3
integrin beta‐3
MAPK
mitogen‐activated protein kinase
MMP2
matrix metalloproteinase‐2
MMP9
matrix metalloproteinase‐9
mRNA
messenger RNA
NF‐κB
nuclear factor kappa‐light‐chain‐enhancer of activated B cells
SBE
SMAD binding element
SERPINE1
serpin family E member 1
siRNA
small interfering RNA
ssGSEA
single‐sample gene set enrichment analysis
TCGA
The Cancer Genome Atlas
TGFβ
transforming growth factor beta
YAP
Yes‐associated protein
YAP8SA
mutants of inhibitory phosphorylation site at eight serine to Alanine of YAP
ZEB1
zinc finger E‐box binding homeobox 1
ZEB2
zinc finger E‐box‐binding homeobox 2
  相似文献   
16.
目的探讨酪氨酸激酶受体RON及上皮型钙粘蛋白(E-cadherin)在子宫内膜异位症(endometriosis,EMs)上的表达及意义。方法选择2017年7~12月深圳市龙岗区人民医院收治的42例EMs患者,术中分别留取新鲜异位内膜组织和在位内膜组织,随机选取子宫切除或诊断性刮宫治疗的非EMs患者42例,术中留取其正常子宫内膜组织。采用逆转录聚合酶链反应(RT-PCR)检测子宫内膜组织中RON mRNA的表达,采用免疫组织化学方法检测对应42例石蜡组织中RON蛋白和E-cadherin的表达,并分析RON蛋白和E-cadherin的相关性。结果EMs异位内膜组织RON mRNA及RON蛋白阳性表达率显著高于在位内膜组织及正常子宫内膜组织(P<0.001),在位内膜组织及正常内膜组织中E-cadherin阳性表达率显著高于异位内膜组织(P<0.001),且异位内膜组织中RON mRNA及RON蛋白的表达与临床分期有关(P<0.001)。在同一标本中RON蛋白和E-cadherin表达呈负相关关系(r=-0.497,P<0.05)。结论RON的过度表达与EMs的发生发展密切相关,联合检测RON和E-cadherin的异常对判断EMs的发生发展有一定的参考价值,RON可能成为诊断治疗EMs的新靶点。  相似文献   
17.
目的 了解某设备实验条件下不同位置脉冲X射线电离辐射水平,提出适当的防护建议。方法 采用热释光测量方法,分别在设备舱周围不同方向不同距离布放热释光剂量计,累积一定数量脉冲辐射后进行测量;采用电离室型X、γ剂量率仪(FJ-347A)实时测量工作状态下不同距离处电离辐射剂量率水平。依据《电离辐射防护与辐射源安全基本标准》(GB18871—2002)规定的职业照射人员和公众个人剂量限值提出不同工作位辐射防护建议。结果 热释光剂量计累计接收3 000个脉冲辐射,设备舱外壁0.01~8.98 mGy,顶部0.01~15.67 mGy,距外壁1~12 m之间0.01~2.18 mGy,工作位0 mGy。工作状态下,X射线剂量率仪测得距设备舱外侧壁1~20 m之间空气比释动能率范围0.26~16 mGy/h。结论 热释光剂量计、电离室型剂量率仪测量结果基本一致,说明两种方法均可用于脉冲X射线测量;工作状态下设备舱外近距离处辐射剂量率较高,可通过采取防护措施或者限制人员工作量以满足辐射防护要求。  相似文献   
18.
目的 研究同型半胱氨酸(homocysteine,Hcy)是否为绝经后女性颈动脉粥样硬化的独立风险因素。 方法 对2017年12月—2018年12月北京协和医院健康体检的1 204名55岁以上绝经后女性,进行Hcy检测和颈动脉超声检查。使用多变量logistic回归方法分析Hcy及其他传统风险因素对颈动脉粥样硬化的影响。 结果 Hcy平均值(12.4±3.3)μmol/L,高Hcy血症176人(14.62%)。Hcy与年龄和BMI正相关(分别r=0.19,P<0.001;r=0.11, P<0.001)。颈动脉粥样硬化患者的Hcy显著升高(Z=-2.56,P=0.011)。logistic回归显示,对于颈动脉粥样硬化只有年龄(OR=1.11,95%CI:1.09~1.14)和收缩压(OR=1.02,95%CI:1.01~1.02)是独立风险因素;对颈动脉斑块形成年龄(OR=1.10,95%CI:1.08~1.12)、收缩压(OR=1.02,95%CI:1.01~1.03)、糖化血红蛋白(OR=1.27,95%CI:1.07~1.50)和高血压病史(OR=1.40,95%CI:1.06~1.87)是独立危险因素。 结论 在绝经后女性,Hcy不是动脉粥样硬化发生的独立风险因素,筛查高Hcy血症在预防该人群颈动脉粥样硬化的意义仍需进一步证明。  相似文献   
19.
Oral cancer, predominantly oral squamous cell carcinoma (OSCC), is one of the most leading causes of cancers worldwide. Due to a low 5-year survival rate, highly effective methods for the early detection of OSCC are totally needed. MicroRNAs (miRNAs), as promising biomarkers, can bring insights into tumorigenesis of oral cancers. However, studies on the accuracy of miRNAs detection in OSCC have inconsistent conclusions, leading us to conduct this meta-analysis. The aim of this study was to systematically review the articles investigating the diagnostic value of miRNAs in OSCC.The PubMed, Embase, Chinese National Knowledge Infrastructure (CNKI), Web of Science were searched (updated to June 11th, 2015) to identify all articles evaluating the diagnostic yield of miRNAs for OSCC. The pooled sensitivity, specificity, and other diagnostic parameters were used to assess the performance of miRNAs assays on OSCC detection. Statistical analysis was conducted by employing the R software.The present meta-analysis comprised 23 studies from 10 articles, including 598 OSCC patients and 320 healthy individuals, available for analysis. The summary receiver operator characteristic (SROC) curve was plotted. Meanwhile, the pooled diagnostic parameters and the area under curve (AUC) were calculated based on all included studies. The pooled diagnostic parameters calculated from all 23 studies were as follows: pooled sensitivity of 0.759 (95% CI: 0.701–0.809), pooled specificity of 0.773 (95% CI: 0.713–0.823) and AUC of 0.832, which indicates a relatively high diagnostic accuracy of miRNAs in differentiating OSCC patients from healthy controls. Meanwhile, In addition, subgroup analyses were conducted to access the heterogeneity between studies, which is based on specimen (serum/plasma/blood/saliva/ tissue) and ethnicity (Asian/Caucasian).In summary, our meta-analysis suggests that miRNAs might be used in noninvasive screening tests for OSCC, which needs further large-scale studies to be validated.  相似文献   
20.
目的:探讨长链非编码RNA(long-chain noncoding,lncRNA)PCGEM1 对肺癌A549 细胞恶性生物学行为的影响及其作用机制。方法:收集2016 年3 月至2018 年5 月湖北医药学院附属太和医院胸外科接受手术治疗的62 例肺癌(lung cancer,LC)患者癌组织及相应的癌旁组织标本,并用以上组织构建LC组织芯片。用qPCR检测lncRNA PCGEM1 及miR-148a 在LC组织相应的癌旁组织及LC细胞株中的表达。构建lncRNA PCGEM1 沉默细胞系A549-siPCGEM1 和阴性对照A549-NC,并以A549 细胞作为空白对照(Control 组),用MTT和平板克隆实验检测敲减PCGEM1 对A549 细胞增殖能力的影响,Transwell 和划痕实验检测敲减PCGEM1 对A549 细胞侵袭和迁移能力的影响。使用生物信息学网站StarBase 预测可互补结合PCGEM1的miRNA,再根据Targetscan 网站预测相应可靶向结合miRNA的基因;Western blotting 实验检测TGF-β2/Smad2 信号通路蛋白表达情况。结果:在LC组织中PCGEM1 的表达水平高于癌旁组织而miR-148a 的表达量明显低于癌旁组织(均P<0.05),PCGEM1 在5 种LC细胞株中的表达明显高于人肺成纤维细胞HLF-02(均P<0.05),且以A549 细胞中表达最高。敲减PCGEM1 后,与Control 组和A549-NC 组比较,A549-siPCGEM1 组A549 细胞增殖、侵袭和迁移能力显著降低(均P<0.05)。StarBase 和Targetscan 网站预测结果显示,PCGEM1 可与miR-148a 互补结合,miR-148a 与TGF-β2 存在靶向结合位点。与Control 组和A549-NC组比较,A549-siPCGEM1 组中miR-148a 表达明显升高,TGF-β2 及p-Smad2 蛋白的表达明显降低(均P<0.05)。结论:lncRNA PCGEM1在LC组织和细胞株中高表达,高表达的PCGEM1 可通过下调miR-148a 水平强化TGF β2/Smad2 信号通路,从而促进A549 细胞恶性生物学行为的进展。  相似文献   
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