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31.
Chemical exchange saturation transfer (CEST) MRI is sensitive to labile proton concentration and exchange rate, thus allowing measurement of dilute CEST agent and microenvironmental properties. However, CEST measurement depends not only on the CEST agent properties but also on the experimental conditions. Quantitative CEST (qCEST) analysis has been proposed to address the limitation of the commonly used simplistic CEST‐weighted calculation. Recent research has shown that the concomitant direct RF saturation (spillover) effect can be corrected using an inverse CEST ratio calculation. We postulated that a simplified qCEST analysis is feasible with omega plot analysis of the inverse CEST asymmetry calculation. Specifically, simulations showed that the numerically derived labile proton ratio and exchange rate were in good agreement with input values. In addition, the qCEST analysis was confirmed experimentally in a phantom with concurrent variation in CEST agent concentration and pH. Also, we demonstrated that the derived labile proton ratio increased linearly with creatine concentration (P < 0.01) while the pH‐dependent exchange rate followed a dominantly base‐catalyzed exchange relationship (P < 0.01). In summary, our study verified that a simplified qCEST analysis can simultaneously determine labile proton ratio and exchange rate in a relatively complex in vitro CEST system. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
32.
The modification of semiconductor nanostructures with metallic nanocomponents can promote the separation of electron/hole from photoexited semiconductors by forming heterojunctions, thus exhibit enhanced photocatalytic activities and potential applications. In this study, Pt-based NPs, including Pt, PtCu, and PtCuCo are employed as model co-catalysts to comparatively study their capability to enhance the photocatalytic activity of TiO2 nanosheets. It was found that each of Pt, PtCu, and PtCuCo can greatly enhance the photocatalytic activity of TiO2 toward degradation of organic dyes. Using electron spin resonance spectroscopy, we demonstrated that deposition of Pt-based NPs resulted in more production of reactive oxygen species including hydroxyl radicals, superoxide, and singlet oxygen. The enhancing effects of Pt-based NPs on generation of ROS and photocatalytic activity showed same trend: PtCuCo?>?PtCu?>?Pt. The mechanism underlying the enhancement differences in Pt-based NPs may be mainly related to electronic structure change of Pt in alloying with Cu and Co. These results are valuable for designing hybrid nanomaterials with high photocatalytic efficiency for applications in water purification and antibacterial products.  相似文献   
33.
随着对于双心疾病研究的加深,西医疗法的弊端也开始显现。而中医因其理论架构中早就有对于“心主血脉”和“心主神明”的认识,因此在双心疾病的治疗上有着先天的优势。同时近些年中医疗法的结合应用也取得不错的成绩,本文通过对于双心疾病的病例分析,来研讨这种治疗手段的合理性和先进性。  相似文献   
34.
目的对比分析单纯关节镜手术与关节镜手术联合Ilizarov外固定架关节牵张术治疗踝关节创伤性关节炎的临床疗效。 方法纳入2016年10月至2018年4月聊城市中医医院收治的早中期踝关节创伤性关节炎患者30例,排除非创伤性关节炎和终末期踝关节炎。其中接受单纯踝关节镜手术者纳入对照组(n=15),接受关节镜手术联合Ilizarov外固定架关节牵张成形术者纳入研究组(n=15),术后随访6个月,对比分析两组患者的治疗效果:疼痛视觉模拟评分(VAS)、踝关节功能评分(Kofoed评分)以及生活质量的变化。计数资料比较采用卡方或Fisher精确检验,计量资料比较采用独立样本t检验。 结果研究组治疗有效率大于对照组(χ2=7.214,P<0.05),术后疼痛视觉模拟评分明显低于对照组(t =10.342,P<0.05),Kofoed评分高于对照组(t =10.452,P<0.05);研究组生活质量显著高于对照组(P<0.05)。 结论关节镜手术联合关节牵张成形术对早中期踝关节创伤性关节炎较单纯关节镜手术短期效果更好,可成为临床治疗中的一种选择,但远期效果尚需进一步研究。  相似文献   
35.
目的对比研究腹腔镜下外生性肾血管平滑肌脂肪瘤"蘑菇状"剜除与标准肾部分切除术的安全性及有效性,为肾血管平滑肌脂肪瘤腹腔镜下"蘑菇状"剜除术术式的建立提供临床依据。 方法选取海南医学院第二附属医院与解放军总医院2018年1月至2019年5月期间,接受腹腔镜手术的肾血管平滑肌脂肪瘤患者53例,其中25例沿肿瘤假包膜行"蘑菇状"剜除术(A组)、28例行肾部分切除术(B组)。比较两组手术患者的肾动脉阻断时间、手术时间、术中出血量、术后24 h血红蛋白、术后eGFR(estimated glomerular filtration rate,估计肾小球率过滤)的变化、术后住院时间和术后肿瘤复发率。 结果53例手术无术中转开放,无死亡病例。肾动脉阻断时间:A组(11.9±2.2)min、B组(21.5±6.5) min(P<0.001)。手术时间:A组(87.9±24.8)min、B组(114.3±38.9) min(P<0.001)。术中出血量:A组20 ml(20~40)ml、B组50 ml(50~100)ml(P<0.001)。术后24 h血红蛋白变化:A组(7.4±4.3) g/L、B组(12.4±8.8) g/L(P=0.013)。术后24 h eGFR变化:A组(6.2±7.2 )ml(min·1.73 m2),B组(12.7±12.8)ml(min·1.73 m2)(P=0.027)。术后6个月eGFR变化:A组(1.5±3.7)ml(min·1.73 m2)、B组(6.5±5.6)ml(min·1.73 m2)(P<0.001)。术后住院时间:A组4.0 d(3~4)d、B组4.5 d(3~6)d(P=0.023)。术后随访两组术后肿瘤均无复发。 结论采用腹腔镜"蘑菇状"剜除术治疗外生性肾血管平滑肌脂肪瘤在肾动脉阻断时间、术中出血量、术后24 h血红蛋白、术后eGFR变化、术后住院时间等方面均优于传统肾部分切除术,两组术后肿瘤均无复发;该方法安全、有效,适于临床推广。  相似文献   
36.
Resident and inflammatory macrophages are essential effectors of the innate immune system. These cells provide innate immune defenses and regulate tissue and organ homeostasis. In addition to their roles in diseases such as cancer, obesity and osteoarthritis, they play vital roles in tissue repair and disease rehabilitation. Macrophages and other inflammatory cells are recruited to tissue injury sites where they promote changes in the microenvironment. Among the inflammatory cell types, only macrophages have both pro-inflammatory(M1) and anti-inflammatory(M2) actions, and M2 macrophages have four subtypes. The co-action of M1 and M2 subtypes can create a favorable microenvironment, releasing cytokines for damaged tissue repair. In this review, we discuss the activation of macrophages and their roles in severe peripheral nerve injury. We also describe the therapeutic potential of macrophages in nerve tissue engineering treatment and highlight approaches for enhancing M2 cell-mediated nerve repair and regeneration.  相似文献   
37.
38.
目的比较内镜手术与显微手术治疗垂体腺瘤的安全性和有效性。方法计算机检索Pubmed、EMbase、CBM、CNKI、万方及VIP等数据库,查找所有比较内镜手术与显微手术治疗垂体瘤的随机对照试验或病例对照研究,检索时限均为建库至2014年5月31日。按纳入排除标准由两人独立进行研究的筛选、资料提取和质量评价后,采用Rev Man5.2软件进行Meta分析。结果共纳入8个研究、712例患者,结果显示,与显微手术相比,内镜手术肿瘤全切率[优势比(OR)=1.23;95%可信区间(CI)(0.62~2.46);P=0.56]、手术时间(P0.05)、术后激素水平改善率[OR=1.21;95%CI(0.58~2.55);P=0.61]、术后脑脊液漏发生率[OR=1.44;95%CI(0.80~2.58);P=0.23]、脑/脑膜炎发生率明显减少[OR=1.15;95%CI(0.38~3.48);P=0.81]、尿崩发生率[OR=1.17;95%CI(0.71~1.94);P=0.53]均无明显改善,而术后鼻出血发生率[OR=0.24;95%CI(0.07~0.78);P=0.02]和术后住院天数明显缩短(P0.05)。结论内镜手术与显微手术相比其术后鼻出血患者较少,术后住院天数短。  相似文献   
39.
Background:Colon cancer is a common malignant tumor of the gastrointestinal tract. Therefore, a clear diagnosis is particularly important for the treatment of colon cancer. Ultrasound and spiral computed tomography (CT) can both be used in the diagnosis, but each has its own advantages and disadvantages, which could cause confusion in clinical choice. The purpose of this study was to systematically evaluate the practicability of spiral CT and ultrasound in the diagnosis of colon cancer.Methods:A systematic search was performed by retrieving on English databases (PubMed, Embase, Web of Science, the Cochrane Library) and Chinese databases (CNKI, Wanfang, Weipu [VIP], CBM). Besides, manually search for Google and Baidu academic of diagnostic experimental study of ultrasound and spiral CT in the diagnosis of Colon Cancer. The retrieval time limit was from the establishment of the database to October 2020. Two researchers independently extracted and evaluated the quality of the data in the included study. A meta-analysis was performed using Meta Disc1.4 and RevMan5.3 software.Results:Sensitivity, specificity, positive Likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were used to determine the diagnostic efficacy of ultrasonography and helical CT in colorectal cancer.Conclusions:This study will compare the practicability of CT and ultrasound in the diagnosis of colon cancer and provide reliable evidence-based basis for clinicians to choose the appropriate or best evidence-based basis.Ethics and dissemination:The private information from individuals will not be published. This systematic review also will not involve endangering participant rights. Ethical approval is not required. The results may be published in a peer-reviewed journal or disseminated in relevant conferences.OSF Registration number:DOI 10.17605/OSF.IO/WAJHQ  相似文献   
40.
通过分析中国马拉松运动员ACE基因I/D多态频率分布特征,探讨其作为杰出耐力基因标记的可行性。选择我国马拉松健将、国际健将级运动员26名作为马拉松运动员组,汉族学生216名作为对照组。对两组受试者进行ACE基因I/D多态性测定。结果显示:我国马拉松运动员组的等位基因频率和基因型频率与对照组比较无显著差异,其中15名国际健将中无一DD型纯合子,提示我国优秀马拉松运动员的纯合子DD型频率低下是其ACE基因多态频率分布的主要特征。  相似文献   
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