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91.
Context: Baicalin has many pharmacological activities, including protective function against myocardial ischemia by antioxidant effects and free radical scavenging activity. However, its rapid elimination half-life in plasma and poor water solubility limits its clinical efficacy.Objective: Novel baicalin-loaded PEGylated nanostructured lipid carriers (BN-PEG-NLC) were developed to improve bioavailability of BN, to prolong retention time in vivo and to enhance its protective effect.Methods: In this study, BN-PEG-NLC were prepared by the emulsion-evaporation and low temperature-solidification method using a mixture of glycerol monostearate and polyethylene glycol monostearate as solid lipids, and oleic acid as the liquid lipid. The physicochemical properties of NLC were characterized. The pharmacokinetic and pharmacodynamic behaviors of BN-PEG-NLC or BN-NLC were evaluated in acute MI rats.Results and discussion: The particle size, zeta potential, and entrapment efficiency for BN-PEG-NLC were observed as 83.9?nm, ?32.1?mV, and 83.5%, respectively. The release profiles of BN from both BN-PEG-NLC and BN-NLC were fitted to the Ritger–Peppas modal, which presented burst release initially and prolonged release afterwards. Pharmacokinetics results indicated that BN-PEG-NLC exhibited a 7.2-fold increase in AUC in comparison to BN solution, while a 3-fold increase in comparison to BN-NLC. Biodistribution results revealed that BN-PEG-NLC exhibited higher heart drug concentration compared with BN-NLC as well as BN solution. In the present study, BN-PEG-NLC significantly ameliorated infarct size.Conclusion: The results of the present study imply that PEG-NLC could be the biocompatible carriers for heart-targeted drug delivery to improve myocardial ischemia. 相似文献
92.
目的分析成人血液系统恶性肿瘤患者接受强烈化疗后中性粒细胞减少性肠炎(NE)的发生率、危险因素及预后情况。方法收集2004至2013年接受化疗的1804例血液系统恶性肿瘤患者,记录患者血常规、凝血检测和血液生化检测结果,并记录患者年龄、性别、原发病、既往化疗次数、既往化疗方案中是否使用阿糖胞苷、临床症状、肠壁厚度、中性粒细胞最低计数、中性粒细胞缺乏持续时间、NE的治疗方法和预后等,探讨NE起病诱因、临床特征、腹部B超特点、症状的预后意义及化疗药物对发病的影响等。结果1804例患者中226例(12.5%)化疗后合并NE,化疗后10~19d起病,中位起病时间为化疗后第14天。发生NE后26例患者死亡,病死率11.5%。化疗药物包括阿糖胞苷、临床症状≥4项、中性粒细胞缺乏持续超过7d以及B超下肠壁厚度≥10mm的患者病死率相对较高。结论NE是接受强烈化疗的血液系统肿瘤患者的严重的并发症,发生NE后患者病死率较高。 相似文献
93.
Shengxuan Cao Chen Wang Xin Ma Xu Wang Jiazhang Huang Chao Zhang Li Chen Xiang Geng Kan Wang 《Journal of orthopaedic research》2019,37(8):1860-1867
Patients with mechanic ankle instability experience increased tibiotalar and subtalar joint laxity. However, in vivo joint kinematics in functional ankle instability (FAI) patients and lateral ankle sprain (LAS) copers, especially during dynamic activities, are poorly understood. Ten FAI patients, 10 LAS copers, and 10 healthy controls were included in this study. A dual fluoroscopic imaging system was used to analyze the tibiotalar and subtalar joint kinematics during stair descent. Five key poses of stair descent were analyzed. Kinematic data from six degrees of freedom were calculated utilizing a solid modeling software. The range of motion and joint positions in each degree of freedom were compared among the three groups. The tibiotalar joints of FAI patients and LAS copers were significantly more inverted than those of healthy controls during the foot strike (p = 0.016, = 0.264). The subtalar joints of FAI patients were significantly more anteriorly translated (pose 2, p = 0.003, = 0.352; pose 3, p < 0.001, = 0.454; pose 4, p = 0.004, = 0.334), inverted (pose 4, p = 0.027, = 0.234; pose 5,p = 0.034, = 0.221), and externally rotated (pose 4, p = 0.037, = 0.217; pose 5; p = 0.004, = 0.331) than those of healthy controls during the mid‐stance and the heel off. The FAI patients showed excessive tibiotalar inversion and subtalar joint hypermobility during stair descent. Meanwhile, the LAS copers maintained subtalar joint stability, and only showed excessive tibiotalar inversion in foot strike. These data provide insight into the mechanisms behind the development of FAI after initial LAS. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 37:1860–1867, 2019 相似文献
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96.
目的 探讨剂量组学在预测肺癌根治性放疗患者放射性肺炎发生中的应用潜能。方法 回顾性收集行根治性放疗的314例肺癌患者的临床资料、放疗剂量文件、定位及随访CT图像,根据临床资料及影像学随访资料对放射性肺炎进行分级,提取全肺的剂量组学特征,构建机器学习模型。应用1000次自助抽样法(bootstrap)的最小绝对值收敛和选择算子嵌套逻辑回归(LASSO‐LR)及1000次bootstrap的赤池信息量准则(AIC)向后法筛选与放射性肺炎相关的剂量组学特征,随机按照7∶3划分为训练集及验证集,应用逻辑回归建立预测模型,并应用ROC曲线及校正曲线评价模型的性能。结果 共提取120个剂量组学特征,经LASSO‐LR降维筛选得到12个特征进入“特征池”,再经过AIC向后法筛选,最终筛选出6个剂量组学特征进行模型构建,训练集AUC为0.77(95%CI为0.65~0.87),独立验证集AUC为0.72(95%CI为0.64~0.81)。结论 利用剂量组学建立的预测模型具有预测放射性肺炎发生的潜力,但仍需继续纳入多中心数据及前瞻性数据进一步挖掘剂量组学的应用潜能。 相似文献
97.
98.
骨碎补是历代临床常用中药,具有疗伤止痛、补肾强骨、消风祛斑等功效。其主要含黄酮、苯丙素、三萜、酚酸及其苷等类化学成分,现代研究表明骨碎补具有抗骨质疏松、促进骨折愈合、促软骨再生、护牙健齿、保护肾功能、抗炎、防治中毒性耳聋、降血脂等多种生物活性,开发前景广阔。本文对近年来骨碎补的化学成分、药理作用及临床应用研究进行综述,以期为骨碎补的进一步深入系统的研究和开发利用提供依据。 相似文献
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