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1.
目的:应用扫频光学相干断层扫描血管成像(SS-OCTA)对比研究白内障术中不同眼内压患者手术前后黄斑区血流的变化情况,为白内障个性化手术参数设计提供临床参考。
方法:前瞻性随机对照研究。收集2021-01/04于四川省人民医院住院行白内障手术的患者61例77眼,使用随机数字表分为A组(37眼)和B组(40眼),术中分别予以75、90cm灌注瓶瓶高,相当于55.5、66.6mmHg术中平均眼内压。所有患者除常规眼科检查外,术前、术后1、7、30d均行黄斑区SS-OCTA检查,观察黄斑区视网膜厚度及放射状毛细血管网(RPCP)层、浅层血管网(SVP)层、中层血管网(IVP)层、深层血管网(DVP)层灌注面积和血管密度。
结果:手术前后各时间点两组患者最佳矫正视力(BCVA)、眼压、黄斑中心凹无血管区(FAZ)面积、黄斑区视网膜厚度及各层灌注面积和血管密度均无组间差异性(均P>0.05),但均有时间差异性(均P<0.05),两组患者术后各时间点BCVA均较术前明显改善,眼压和FAZ面积均较术前下降(均P<0.05),黄斑区视网膜厚度及各层灌注面积和血流密度均较术前增加。
结论:白内障术后黄斑区视网膜厚度及各层血流密度和灌注面积均增加,FAZ面积下降,有助于促进术后视力的恢复,且术中选择55.5、66.6mmHg不同眼内压情况下,患者术后眼底血流改变情况无明显差异,故术中可以灵活选择眼内压,为患者提供个性化手术设计方案。 相似文献
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Species identification of unknown biological samples is crucial for forensic applications, especially in cases of explosion, disaster accidents, and body mutilation after murdering, as well as poaching, illegal trade in endangered animals, and meat food fraud. In this study, we identified 60 volatile organic compounds (VOCs) in fresh skeletal muscle tissues of seven different animal species (cattle, sheep, pigs, rabbits, rats, chickens and carp) and a human dead body by headspace-gas-chromatography ion-mobility spectrometry (HS-GC-IMS), and compared their differences by retention time, drift time and molecular weight. The results showed that these VOCs formed different gallery plot fingerprints in the skeletal muscle tissues of the human dead body and seven animal species. Principal component analysis (PCA) showed significantly different fingerprints between these species, and these fingerprints maintained good stability between the species and within the same species. Some VOCs have high species specificity, while VOCs of human fresh muscle tissues from different individual sources have little difference, demonstrating that all tested muscle tissue samples could be distinguished based on different VOCs. HS-GC-IMS has proved to be a rapid, high-throughput, highly sensitive and specific species identification method, which can be used for forensic species identification in criminal cases and disaster accidents, as well as detection in the field of food safety, such as meat fraud and adulteration. 相似文献
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IntroductionDue to their biocompatible and plasmonic properties, gold nanoparticles (Au NPs) are good candidates to be photosensitizers in photothermal cancer therapy (PTT).Materials and methodsIn this paper, the dependence of the NIR-light-to-heat energy on Au NPs size was investigated. Moreover, to determine the photosensitizing properties of gold nanoparticles, PTT was conducted on two colon cell lines: SW480 and SW620 by irradiating them with two lasers having different wavelengths.ResultsTransmission electron microscopy showed that the respective sizes of Au NPs were 10 nm, 12 nm and 16 nm. Moreover, local as well as global structural measurements showed that all synthesized Au NPs were crystalline and UV-Vis spectroscopy revealed that with increasing nanoparticles size the position of the surface Plasmon resonance (SPR) peaks is shifted to higher wavelengths. Decrease of cells viability was observed, when they were cultured with Au NPs and irradiated by 650 nm and 808 nm lasers. Moreover, FTIR and Raman spectra of cells, showed structural changes in DNA, phospholipids, proteins and cholesterol caused by the addition of nanoparticles and laser irradiation. The chemical changes were more pronounced in the cells cultured with Au NPs and irradiated by 650 nm lasers and these changes were dependent on the nanoparticle size. Moreover, the viability of cells investigated by the MTS assay showed, that the percentage of dead cells (∼40%) is the highest for cells cultured with 8 nm Au NPs and irradiated by the 650 nm laser. The photothermal conversion efficiency calculated from the experimental results showed a decrease of this parameter from 70% to 55% and from 61% to 48% with increasing particle size, for 650 nm and 808 nm lasers, respectively.ConclusionsThe obtained results showed that the photothermal conversion efficiency of Au NPs is size-tunable, and can be correlated with the absorption/extinction ratios calculated by the Mie theory. 相似文献
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《The lancet oncology》2022,23(2):209-219
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目的 探究基于虚拟现实(VR)的视觉训练对集合不足受试者视功能与主观问卷的影响以及长期疗效的观察。 方法 研究共纳入集合不足受试者36例,将受试者随机分入基于虚拟现实的视觉训练组(VR组)及传统训练组(OBVAT组)。训练时长为每周1 h,共12周。在训练前、训练第6周、训练第12周及训练结束后6个月完成双眼视功能参数及主观问卷调查(CISS)。 结果 重复测量方差分析结果显示,集合不足的受试者(包括VR组与OBVAT组)进行视觉训练12周后,CISS得分降低、集合近点减小、正融像性聚散范围值增加,视近外隐斜减小(P<0.001)。VR组与OBVAT组集合不足的受试者在训练结束后6个月的视功能参数与训练12周相比无统计学差异(P>0.05)。VR组与OBVAT组之间各项参数的组间差异无统计学意义(P>0.05)。 结论 研究结果显示基于虚拟现实的视觉训练可以显著改善集合不足受试者的主观症状与视功能参数,与传统训练方法相比无统计学差异;在训练结束后6个月,仍可维持一定效果。 相似文献
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目的 探索模拟教学法在临床相关本科专业流行病学课程教学中的应用及效果。方法 将平行开课的4个临床相关专业大班按整群随机的方法分为试验组(n=162)和对照组(n=166),对照组按传统方法教学,试验组给予基于模拟流行病学调查/试验的案例讨论教学法,课终采用问卷结合考试成绩评价教学效果。组间比较采用卡方检验、t检验或秩和检验。结果 试验组对于流行病学课程的学习兴趣(Z=-3.820,P<0.001)、课程的重要性和意义评价(Z=-4.713,P<0.001)、该课程难易程度评价(Z=-4.220,P<0.001)、开展流行病学调查和实施医学研究的信心(Z=-4.316,P<0.001)、课终考试成绩(Z=-3.631,P=0.002)均高于对照组; 并认为课程有助于提升文献阅读能力(Z=-4.618,P<0.001)、独立思考与解决问题能力(Z=-5.892,P<0.001),对科研设计与实施(Z=-3.851,P<0.01)、对学习其他课程(Z=-6.177,P<0.001)以及对逻辑思维、系统思维、多元思维形成(Z=-4.506,P<0.001)等有较大帮助,和对照组比较,差异均有统计学意义。结论 基于模拟流行病学调查/试验的案例讨论教学法,能够帮助学生整体上理解和掌握流行病学课程内容,提高学生分析和解决实际问题的能力,值得进一步探索和应用。 相似文献
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Microhaplotypes have been highly regarded for forensic mixture DNA deconvolution because they do not experience interference from stutters in the same way as short tandem repeat markers, and they tend to be more polymorphic than single nucleotide polymorphism markers. However, forensic microhaplotype kits have not been reported. The MHSeqTyper47 kit genotypes 47 microhaplotype loci. In this study, MiSeq FGx sequencing metrics for MHSeqTyper47 were presented, and the genotyping accuracy of this kit was examined. The sensitivity of MHSeqTyper47 reached 62.5 pg, and full genotyping results were obtained from degraded DNA samples with degradation indexes ≤ 3.00. Full genotypes were obtained in the presence of 100 ng/μL tannin, 50 μM heme, 25 ng/μL humic acid, and 1.25 μg/μL indigo dye. In DNA mixture studies, a minimum of 31 loci of the minor contributor were correctly genotyped at 1:99 or 99:1 mixing ratios, with the cumulative random matching probability of these loci reaching 4.54 × 10−25. Mixing ratios could be reliably predicted from two-donor DNA mixtures based on the loci with four called alleles. Taken together, these data showed that the MHSeqTyper47 kit was effective for forensically challenging DNA analysis. 相似文献
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Su Jinmei Li Mengtao He Lan Zhao Dongbao Wan Weiguo Liu Yi Xu Jianhua Xu Jian Liu Huaxiang Jiang Lindi Wu Huaxiang Zuo Xiaoxia Huang Cibo Liu Xiumei Li Fen Zhang Zhiyi Liu Xiangyuan Dong Lingli Li Tianwang Chen Haiying Li Jingyang He Dongyi Lu Xin Huang Anbin Tao Yi Wang Yanyan Zhang Zhuoli Wei Wei Li Xiaofeng Zeng Xiaofeng 《Clinical rheumatology》2022,41(3):731-739
Clinical Rheumatology - The equivalence of the biosimilar HS016 to adalimumab (Humira) for the treatment of active ankylosing spondylitis (AS) patients has been previously validated. The aim was to... 相似文献