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81.
目的 研究1 g·L-1和3 g·L-1玻璃酸钠(hyaluronate,HA)滴眼液对角膜内皮移植术后早期泪膜及角膜上皮细胞再生的作用。方法 选择2017年9月至2018年2月在北京大学第三医院行角膜内皮移植术的患者60例(60眼),随机分成1 g·L-1HA组和3 g·L-1HA组,每组各30例,观察标准干眼评估问卷(SPEED)评分、结膜角膜染色评分(OSS)、泪膜破裂时间(TBUT)、角膜上皮缺损范围,进行激光共聚焦显微镜检查。比较不同时间点组间、组内各指标差异。结果 SPEED评分:各时间点两组间比较差异均无统计学意义(均为P>0.05)。组内比较:两组组内术后7 d、14 d、28 d均低于前一时间点(均为P=0.000),余相邻时间点两两比较差异均无统计学意义(均为P>0.05)。TBUT:术后7 d、14 d、28 d 3 g·L-1HA组均显著高于1 g·L-1HA组(均为P<0.05),而术前组间差异不显著;组内比较:1 g·L-1 HA组后一时间点较前一时间点、3 g·L-1HA组术后7 d较术前均显著延长(均为P<0.05),而3 g·L-1HA组术后14 d、28 d与前一时间点差异均无统计学意义(均为P>0.05)。 OSS评分:术前及术后1 d、3 d两组间比较差异均无统计学意义(均为P>0.05),术后7 d、14 d、28 d 3 g·L-1HA组均显著低于1 g·L-1HA组(均为P<0.05);组内比较:两组术后1 d OSS评分均显著高于术前(均为P=0.000),其余时间点两组均低于前一时间点(均为P=0.000)。角膜上皮缺损范围:术后1 d 两组间比较差异均无统计学意义(均为P>0.05),术后3 d、7 d 两组间比较,以及两组组内与前一时间点比较差异均有统计学意义(均为P<0.05)。角膜基底细胞密度:术前、术后28 d两组间比较,以及1 g·L-1HA组组内术前与术后28 d比较差异均无统计学意义(均为P>0.05),而3 g·L-1 HA组术后28 d显著低于术前(P=0.002)。结论 HA可以有效改善角膜内皮移植术后早期泪膜状态并促进角膜上皮细胞再生,存在浓度依赖性。 相似文献
82.
83.
《Clinical neurophysiology》2020,131(1):213-224
ObjectiveSystematically review the abnormalities in event related potential (ERP) recorded in Rett Syndrome (RTT) patients and animals in search of translational biomarkers of deficits related to the particular neurophysiological processes of known genetic origin (MECP2 mutations).MethodsPubmed, ISI Web of Knowledge and BIORXIV were searched for the relevant articles according to PRISMA standards.ResultsERP components are generally delayed across all sensory modalities both in RTT patients and its animal model, while findings on ERPs amplitude strongly depend on stimulus properties and presentation rate. Studies on RTT animal models uncovered the abnormalities in the excitatory and inhibitory transmission as critical mechanisms underlying the ERPs changes, but showed that even similar ERP alterations in auditory and visual domains have a diverse neural basis. A range of novel approaches has been developed in animal studies bringing along the meaningful neurophysiological interpretation of ERP measures in RTT patients.ConclusionsWhile there is a clear evidence for sensory ERPs abnormalities in RTT, to further advance the field there is a need in a large-scale ERP studies with the functionally-relevant experimental paradigms.SignificanceThe review provides insights into domain-specific neural basis of the ERP abnormalities and promotes clinical application of the ERP measures as the non-invasive functional biomarkers of RTT pathophysiology. 相似文献
84.
长链非编码RNA(LncRNA)是一种长度超过200个核苷酸的内源RNA。大量研究表明,LncRNA可参与多种生物过程,如转录激活和干扰、细胞分化、增殖、迁移、侵袭和凋亡。近年来许多研究表明LncRNA在人类癌症中作为致癌基因或肿瘤抑制基因发挥着重要作用。大量新研究表明LncRNA肌动蛋白丝相关蛋白1反义RNA1(AFAP1-AS1)参与了多种恶性肿瘤的发生发展。已证实AFAP1-AS1的失调表达与肿瘤发生和肿瘤进展相关;AFAP1-AS1可能成为肿瘤诊断和肿瘤治疗靶点的新型潜在分子生物标志物。在本篇综述中,我们总结了现阶段关于AFAP1-AS1在人类肿瘤发生和发展过程中的生物学功能和分子机制的研究问题。 相似文献
85.
目的 探讨长链非编码RNA RAB11B-AS1(lncRNA RAB11B-AS1)在膀胱癌组织中的表达及其与临床病理参数和预后的关系。方法 收集2012年10月—2014年2月于云南省第二人民医院泌尿外科手术切除的83例膀胱癌组织及相应癌旁正常组织。采用qRT-PCR检测lncRNA RAB11B-AS1的表达并分析其与患者临床病理特征的关系,采用Cox回归分析lncRNA RAB11B-AS1表达水平与膀胱癌患者预后的关系。结果 lncRNA RAB11B-AS1在膀胱癌组织中的表达水平低于癌旁正常组织(1.17±0.32 vs 2.09±0.74,t=10.396,P<0.001);膀胱癌癌组织中lncRNA RAB11B-AS1的表达水平与患者TNM分期、组织学分级和淋巴结是否转移有关(P<0.05)。lncRNA RAB11B-AS1高表达患者5年总生存率高于低表达患者(62.22% vs 26.32%,χ2=13.420,P<0.001);多因素Cox回归分析显示,lncRNA RAB11B-AS1低表达是影响膀胱癌患者预后的独立危险因素(HR=1.126,95%CI:1.058~1.200,P<0.001)。结论 lncRNA RAB11B-AS1在膀胱癌组织中低表达,且低表达患者预后较差。 相似文献
86.
A Stable Q Compensated Reverse Time Migration Method Based on Excitation Amplitude Imaging Condition 下载免费PDF全文
Qingqing Li Li-Yun Fu Weijia Sun Wei Wei & Wanting Hou 《Communications In Computational Physics》2020,28(1):141-166
The stability and efficiency, especially the stability, are generally concerned
issues in Q compensated reverse time migration (Q-RTM). The instability occurs because of the exponentially boosted high frequency ambient noise during the forward
or backward seismic wavefield propagation. The regularization and low-pass filtering
methods are two effective strategies to control the instability of the wave propagation in Q-RTM. However, the regularization parameters are determined experimentally, and the wavefield cannot be recovered accurately. The low-pass filtering method
cannot balance the selection of cutoff frequency for varying Q values, and may damage
the effective signals, especially when the signal-to-noise ratio (SNR) of the seismic data
is low, the Q-RTM will be a highly unstable process. In order to achieve the purpose
of stability, the selection of cutoff frequency will be small enough, which can cause
great damage to the effective high frequency signals. In this paper, we present a stable Q-RTM algorithm based on the excitation amplitude imaging condition, which can
compensate both the amplitude attenuation and phase dispersion. Unlike the existing Q-RTM algorithms enlarging the amplitude, the exponentially attenuated seismic
wavefield will be used during both the forward and backward wavefield propagation
of Q-RTM. Therefore, the new Q-RTM algorithm is relative stable, even for the low
SNR seismic data. In order to show the accuracy and stability of our stable Q-RTM
algorithm clearly, an example based on Graben model will be illustrated. Then, a realistic BP gas chimney model further demonstrates that the proposed method enjoys
good stability and anti-noise performance compared with the traditional Q-RTM with
amplitude amplification. Compare the Q-RTM images of these two models to the reference images obtained by the acoustic RTM with acoustic seismic data, the new Q-RTM
results match the reference images quite well. The proposed method is also tested
using a field seismic data, the result shows the effectiveness of our proposed method. 相似文献
87.
Left Atrial Appendage Flow Velocity and Time from P‐Wave Onset to Tissue Doppler–Derived A' Predict Atrial Fibrillation Recurrence after Radiofrequency Catheter Ablation 下载免费PDF全文
Keiko Fukushima M.D. Ph.D. Noritoshi Fukushima M.D. Ph.D. Koichiro Ejima M.D. Ph.D. Ken Kato M.D. Yasuto Sato Ph.D. Shoko Uematsu M.D. Kotaro Arai M.D. Ph.D. Tetsuyuki Manaka M.D. Ph.D. Atsushi Takagi M.D. Ph.D. Kyomi Ashihara M.D. Ph.D. Morio Shoda M.D. Ph.D. Nobuhisa Hagiwara M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(7):1101-1108
88.
Oral Everolimus for Treatment of a Giant Left Ventricular Rhabdomyoma in a Neonate—Rapid Tumor Regression Documented by Real Time 3D Echocardiography 下载免费PDF全文
Robert Wagner M.D. Ph.D. Frank Thomas Riede M.D. Hiroshi Seki M.D. Frauke Hornemann M.D. Steffen Syrbe M.D. Ingo Daehnert M.D. Ph.D. Michael Weidenbach M.D. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2015,32(12):1876-1879
The presented case reports on successful treatment with everolimus in a neonate with left ventricular giant rhabdomyoma. The authors used a different dosage regime compared to literature and documented rapid tumor regression by 3D echocardiography. 相似文献
89.
Melatonin compensates silencing of heat shock protein 70 and suppresses ultraviolet radiation‐induced inflammation in human skin ex vivo and cultured keratinocytes 下载免费PDF全文
Konrad Kleszczyński Stephanie Zwicker Stefan Tukaj Michael Kasperkiewicz Detlef Zillikens Ronald Wolf Tobias W. Fischer 《Journal of pineal research》2015,58(1):117-126
Melatonin, a lipophilic compound synthesized and released from the pineal gland, effectively acts against ultraviolet radiation (UVR), one of the main inducers of epidermal damage, skin cancer, inflammation, and DNA photo damage. One of the common known stress protein induced by UVR is heat shock protein 70 (Hsp70), highly expressed in human keratinocytes, providing cellular resistance to such stressors. Here, using human full‐thickness skin and normal human epidermal keratinocytes (NHEK), we investigated the interaction of melatonin and Hsp70 toward UVR‐induced inflammatory and apoptotic responses. The following observations were made: (i) UVR upregulated Hsp70 gene expression in human epidermis while melatonin significantly inverted this effect, (ii) similar patterns of regulation were observed within Hsp70 protein level, and (iii) mechanistic studies involving silencing of Hsp70 RNA (Hsp70 siRNA) showed prominent decrease of IκB‐α (an inhibitor of NF‐κB) and enhanced gene expression of pro‐inflammatory cytokines (IL‐1β, IL‐6, Casp‐1) and pro‐apoptotic protein (Casp‐3) in NHEK. Parallel investigation using melatonin (10?3 m ) significantly inverted these responses regardless depletion of Hsp70 RNA suggesting a compensatory action of this compound in the defense mechanisms. Our findings combined with data reported so far thus enrich existing knowledge about the potent anti‐apoptotic and anti‐inflammatory action of melatonin. 相似文献
90.