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991.
目的:探讨冠心病患者握力、功能肺活量(FVC)、第一秒用力呼吸量(FEV1)、呼气峰流速(PEF)、6 min步行距离(6MWD)、左心室射血分数(LVEF)的相关性。方法:回顾性收集2017年1月至2018年12月北京医院心内科住院的冠心病患者35例,年龄(70.4±10.6)岁,根据年龄分为非老年组(<65岁)8例...  相似文献   
992.
993.
In this paper, the electrochemical corrosion behavior of X70 steel in saline soil under capillary water was simulated by a Geo-experts one-dimensional soil column instrument. A volumetric water content sensor and conductivity test were used to study the migration mechanism of water and salt (sodium chloride) under the capillary water. The electrochemical corrosion behavior of the X70 steel in the corrosion system was analyzed by electrochemical testing as well as the macroscopic and microscopic corrosion morphology of the steel. The test results showed that the corrosion behavior of X70 steel was significantly influenced by the rise of capillary water. In particular, the wetting front during the capillary water rise meant that the X70 steel was located at the three-phase solid/liquid/gas interface at a certain location, which worsened its corrosion behavior. In addition, after the capillary water was stabilized, the salts were transported with the capillary water to the top of the soil column. This resulted in the highest salt content in the soil environment and the most severe corrosion of the X70 steel at this location.  相似文献   
994.
To improve transportation efficiency, a supercritical CO2 pipeline is the best choice for large-scale and long-distance transportation inshore and offshore. However, corrosion of the pipe wall will occur as a result of the presence of free water and other impurities present during CO2 capture. Defects caused by corrosion can reduce pipe strength and result in pipe failure. In this paper, the burst pressure of subsea supercritical CO2 pipelines under high pressure is investigated. First, a mechanical model of corroded CO2 pipelines is established. Then, using the unified strength theory (UST), a new burst pressure equation for subsea supercritical CO2 pipelines is derived. Next, analysis of the material’s intermediate principal stress parameters is conducted. Lastly, the accuracy of the burst pressure equation of subsea supercritical CO2 pipelines is proven to meet the engineering requirement by experimental data. The results indicate that the parameter b of UST plays a significant role in determining burst pressure of pipelines. The study can provide a theoretical basis and reference for the design of subsea supercritical CO2 pipelines.  相似文献   
995.
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2, SARS2) remains a great global health threat and demands identification of more effective and SARS2-targeted antiviral drugs, even with successful development of anti-SARS2 vaccines. Viral replicons have proven to be a rapid, safe, and readily scalable platform for high-throughput screening, identification, and evaluation of antiviral drugs against positive-stranded RNA viruses. In the study, we report a unique robust HIV long terminal repeat (LTR)/T7 dual-promoter-driven and dual-reporter firefly luciferase (fLuc) and green fluorescent protein (GFP)-expressing SARS2 replicon. The genomic organization of the replicon was designed with quite a few features that were to ensure the replication fidelity of the replicon, to maximize the expression of the full-length replicon, and to offer the monitoring flexibility of the replicon replication. We showed the success of the construction of the replicon and expression of reporter genes fLuc and GFP and SARS structural N from the replicon DNA or the RNA that was in vitro transcribed from the replicon DNA. We also showed detection of the negative-stranded genomic RNA (gRNA) and subgenomic RNA (sgRNA) intermediates, a hallmark of replication of positive-stranded RNA viruses from the replicon. Lastly, we showed that expression of the reporter genes, N gene, gRNA, and sgRNA from the replicon was sensitive to inhibition by Remdesivir. Taken together, our results support use of the replicon for identification of anti-SARS2 drugs and development of new anti-SARS strategies targeted at the step of virus replication.  相似文献   
996.
目的:评价不同缺牙间隙大小对上前牙区连续缺牙伴水平骨量不足、行水平骨增量延期种植的临床效果影响.方法:回顾性分析2013年1月~2019年6月期间,于烟台市口腔医院种植科就诊,上颌前牙连续缺失,行水平骨增量延期种植的患者,根据缺牙间隙分为两组,A组为2颗牙连续缺失,B组为3~6颗牙连续缺失.通过Mimics软件重建骨增...  相似文献   
997.
ContextThe risk of contrast-induced acute kidney injury (CI-AKI) is increasing and the harm is great. Quercetin is the main active component in Abelmoschus manihot (L.) Medik (Malvaceae) and was reported to reduce the expression of HIF-1α.ObjectiveWe investigate whether quercetin improves the CI-AKI through the HIF-1α/lncRNA NEAT1/HMGB1 pathway.Materials and methodsHK-2 cells were treated with iohexol (200 mg/mL) for 6 h to establish a CI-AKI model. Quercetin (20 μM) was administered to CI-AKI cells cultured in dishes for 24 h. Cell morphology was observed by a fluorescence microscope. MTT and TUNEL assays were used to detect cell survival rate and apoptosis. Relative mRNA levels were measured by qRT-PCR. Protein levels were detected using western blotting. IL-6 and TNF-α protein levels were tested by Elisa assay. Targeting binding sites of HIF-1α and lncRNA NEAT1 were detected by luciferase assay.ResultsThe IC50 value of quercetin was 163.25 μM. The expression levels of HIF-1α, lncRNA NEAT1 and HMGB1 were upregulated in the CI-AKI cell model. Quercetin diminished cell injury and apoptosis via inhibiting HIF-1α. Silencing of HIF-1α targeting lncRNA MEAT1 diminished cell injury and apoptosis. Silencing lncRNA NEAT1 has the same effect via suppressing HMGB1 expression. Collectively, quercetin diminished cell injury and apoptosis in CI-AKI cell model via the inhibition of HIF-1α on lncRNA NEAT1/HMGB1 signalling pathway.Discussion and conclusionsQuercetin diminished cell injury and apoptosis in CI-AKI cell mode via the inhibition of HIF-1α on the lncRNA NEAT1/HMGB1 signalling pathway, offering a potential novel therapeutic target for CI-AKI therapy.  相似文献   
998.
超声诊断颌下腺炎的临床应用   总被引:1,自引:0,他引:1  
目的探讨超声诊断颌下腺炎的临床应用价值。方法选取101例经手术证实的颌下腺炎的超声图像,分析颌下腺的大小、形态、内部回声及彩色血流情况。结果101例颌下腺炎中,急性炎症2例,慢性炎症99例,超声与手术病理结果符合率为98%。结论超声对颌下腺炎的诊断准确率较高,并能与颌下区占位性病变相鉴别。  相似文献   
999.
目的:探讨利妥昔单抗(RTX)治疗儿童难治性激素耐药型肾病综合征(SRNS)的疗效和安全性。方法:回顾性分析2013年9月至2018年3月东部战区总医院儿科收治并接受RTX治疗的10例难治性SRNS患儿的临床资料。结果:10例患儿发病年龄(4.47±2.75)岁,男女各5例;5例(50%)肾活检为局灶节段性肾小球肾炎,...  相似文献   
1000.
目的:探讨应用网络信息化平台的全国多中心基于案例学习(case-based learning, CBL)教学方法的实施效果。方法:本研究采用问卷调查方法。2017年6月至2019年10月,选取全国11个省份的51家医院参加基于网络信息化平台的CBL教学方法的201名神经内科住院医师为研究对象。在教学开始前和结束后分别对...  相似文献   
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