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1.
目的:研究川芎嗪对七氟烷引起的氧化损伤以及血脑屏障(BBB)生理功能损伤的影响及其机制。方法:将新生幼鼠随机分组,设置对照组,并分别使用七氟烷、七氟烷和溶剂、七氟烷和川芎嗪处理小鼠,暴露于七氟烷中不同时长处死并收集小鼠大脑和海马组织,通过免疫酶联吸附检测ROS,SOD,MDA,GSH和S100β蛋白水平,制作小鼠大脑和海马组织切片并通过免疫化学染色和免疫荧光染色检测小鼠大脑和海马组织中MMP-2、MMP-9、TIMP-1、TIMP-2以及HO-1的表达,并检测Nrf2的核易位,HE染色后通过透射电子显微镜检查海马神经元损伤情况,通过蛋白质印迹分析PKC/Nrf2以及MMP-2、MMP-9表达情况,使用原位酶谱检测明胶酶活性并通过PCR检测ZO-1的表达。结果:与对照组相比,七氟烷组海马神经元损伤明显,而川芎嗪处理可以明显改善七氟烷诱导的海马神经元损伤; 与对照组相比,七氟烷处理后MMP-2、MMP-9表达和明胶酶活性明显增加,ZO-1表达明显减少,BBB通透性显著增加,而TIMP-1和TIMP-2表达无显著改变; 与七氟烷组相比,川芎嗪可以抑制明胶酶活性,促进ZO-1表达,改善BBB生理状态; 与溶剂组和七氟烷组相比,对照组和川芎嗪组ROS和BMD水平明显降低,MDA和GSH活性显著增加,PKCα、Nrf2和HO-1 的表达以及Nrf2的核易位显著增加。结论:川芎嗪可以通过PKCα/Nrf2信号通路以及抑制明胶酶活性,改善BBB通透性,保护海马免受氧化应激的伤害,改善海马体组织病理学结构。  相似文献   
2.
In the previous research, we found that anticancer agent LS-1-2F could cause the vacuolation of tumor cells. Herein we investigated the effect of compound LS-1-2F on the endocytosis of macromolecules, including fluorescence quantum dots, human serum albumin, single-stranded RNA, and monoclonal antibody, into tumor cells. We found that LS-1-2F could accelerate the endocytosis of these large molecules by laser confocal microscope and flow cytometry. The effect of LS-1-2F on the improvement of the internalization efficiency of Herceptin biosimilar was particularly significant. Promoting endocytosis will help increase the efficiency of liquid-phase drug uptake in drug-resistant cancer cells and could potentially facilitate the use of drugs in nanoparticle delivery vehicles.  相似文献   
3.
目的:研析奥氮平治疗老年晚期癌症患者抑郁状态的血药浓度与临床疗效的关系,促进合理用药。方法:80例这类患者服用2.5 ~ 10 mg·d-1奥氮平,应用全自动二维液相色谱法(2D-LC/UV)检测患者用药后4周内每周奥氮平血药浓度(C奥氮平);采用汉密尔顿抑郁量表(HAMD-24)于治疗前、治疗后4周内每周评估疗效,应用线性回归方程分析奥氮平剂量与血药浓度相关性,运用Logistic回归和受试者工作曲线(ROC)分析奥氮平血药浓度与临床疗效相关性;采用副反应量表(TESS)评估药物不良反应。结果:奥氮平日剂量(D日)和C奥氮平线性方程呈正相关(r=0.634,P<0.001)。治疗的第1、2、3、4周末,有效组与无效组患者D日、C奥氮平、HAMD-24量表减分率存在显著性差异(P<0.05)。经Logistic回归分析得出年龄大、奥氮平血药浓度低是导致奥氮平治疗效果不理想的影响因素。以C奥氮平作为疗效预测因子绘制治疗第1、2、3、4周末ROC曲线,得出约登指数最大时对应的最佳临界值切点分别11.18、13.89、11.55、12.44 ng·mL-1;未发现C奥氮平与TESS量表评分相关(P>0.05)。结论:奥氮平血药浓度与日剂量、临床疗效密切相关,治疗老年晚期癌症患者抑郁状态最低有效血药浓度范围为11~14 ng·mL-1。  相似文献   
4.
To examine the knowledge level, behaviors, and psychological status of the Chinese population during the COVID-19 pandemic, and to explore the differences between urban and rural areas.We carried out a cross-sectional survey of the knowledge, behaviors related to COVID-19, and mental health in a probability sample of 3001 community residents in 30 provinces or districts across China from February 16–23, 2020. Convenience sampling and a snowball sampling were adopted. We used General Anxiety Disorder (GAD), the 9-item Patient Health Questionnaire (PHQ-9), and knowledge and behaviors questionnaire of community residents regarding COVID-19 designed by us to investigate the psychological status, disease-related knowledge, and the behavior of Chinese urban and rural residents during the pandemic.The average score of anxiety and depression among urban residents was 9.15 and 11.25, respectively, while the figures in rural areas were 8.69 and 10.57, respectively. There was a statistically significant difference in the levels of anxiety (P < .01) and depression (P < .01). Urban participants reported significantly higher levels of knowledge regarding COVID-19 in all aspects (transmission, prevention measures, symptoms of infection, treatment, and prognosis) (P < .01), compared to their rural counterparts. While a majority of respondents in urban areas obtained knowledge through WeChat, other apps, and the Internet (P < .01), residents in rural areas accessed information through interactions with the community (P < .01). Urban residents fared well in exchanging knowledge about COVID-19 and advising others to take preventive measures (P < .01), but fared poorly in advising people to visit a hospital if they displayed symptoms of the disease, compared to rural residents (P < .01). Regression analysis with behavior showed that being female (OR = 2.106, 95%CI = 1.259–3.522), aged 18 ≤ age < 65 (OR = 4.059, 95%CI = 2.166–7.607), being satisfied with the precautions taken by the community (OR = 2.594, 95%CI = 1.485–4.530), disinfecting public facilities in the community (OR = 2.342, 95%CI = 1.206–4.547), having knowledge of transmission modes (OR = 3.987, 95%CI: 2.039, 7.798), symptoms (OR = 2.045, 95%CI = 1.054–4.003), and outcomes (OR = 2.740, 95%CI = 1.513–4.962) of COVID-19, and not having anxiety symptoms (OR = 2.578, 95%CI = 1.127–5.901) were positively associated with affirmative behavior in urban areas. Being married (OR = 4.960, 95%CI = 2.608–9.434), being satisfied with the precautions taken by the community (OR = 2.484, 95%CI = 1.315–4.691), screening to ensure face mask wearing before entering the community (OR = 8.809, 95%CI = 2.649–19.294), and having knowledge about precautions (OR = 4.886, 95%CI = 2.604–9.167) and outcomes (OR = 2.657, 95%CI = 1.309–5.391) were positively associated with acceptable conduct in rural areas.The status of anxiety and depression among urban residents was more severe compared to those living in rural areas. There was a difference in being positively associated with constructive behaviors between rural and urban areas.  相似文献   
5.
目的分析和探讨康复专科护士学员在临床实践教学中应用情境模拟教学的效果。方法随机将2019年1—12月我院康复医学中心招收的80名康复专科护士学员随机分为观察组和实验组,观察组(40名)采用常规临床带教,实验组(40名)采用情境模拟教学方法。结果实验组学员理论知识平均得分、实践操作平均得分及康复专科护士学员对带教老师满意度均高于观察组(P<0.05)。结论在临床实践教学过程中应用情境模拟教学,能有效提升康复专科护士的理论知识水平及临床实践操作能力,提高教学质量和教学水平,提升教学效果。  相似文献   
6.
Glucocorticoids (GCs) have been the mainstay of immunosuppressive therapy in solid organ transplantation (SOT) for decades, due to their potent effects on innate immunity and tissue protective effects. However, some SOT centers are reluctant to administer GCs long-term because of the various related side effects. This review summarizes the advantages and disadvantages of GCs in SOT. PubMed and Scopus databases were searched from 2011 to April 2021 using search syntaxes covering “transplantation” and “glucocorticoids”. GCs are used in transplant recipients, transplant donors, and organ perfusate solution to improve transplant outcomes. In SOT recipients, GCs are administered as induction and maintenance immunosuppressive therapy. GCs are also the cornerstone to treat acute antibody- and T-cell-mediated rejections. Addition of GCs to organ perfusate solution and pretreatment of transplant donors with GCs are recommended by some guidelines and protocols, to reduce ischemia-reperfusion injury peri-transplant. GCs with low bioavailability and high potency for GC receptors, such as budesonide, nanoparticle-mediated targeted delivery of GCs to specific organs, and combination use of dexamethasone with inducers of immune-regulatory cells, are new methods of GC application in SOT patients to reduce side effects or induce immune-tolerance instead of immunosuppression. Various side effects involving different non-targeted organs/tissues, such as bone, cardiovascular, neuromuscular, skin and gastrointestinal tract, have been noted for GCs. There are also potential drug-drug interactions for GCs in SOT patients.  相似文献   
7.
ObjectiveTo construct deep learning (DL) models to improve the accuracy and efficiency of thyroid disease diagnosis by thyroid scintigraphy.MethodsWe constructed DL models with AlexNet, VGGNet, and ResNet. The models were trained separately with transfer learning. We measured each model’s performance with six indicators: recall, precision, negative predictive value (NPV), specificity, accuracy, and F1-score. We also compared the diagnostic performances of first- and third-year nuclear medicine (NM) residents with assistance from the best-performing DL-based model. The Kappa coefficient and average classification time of each model were compared with those of two NM residents.ResultsThe recall, precision, NPV, specificity, accuracy, and F1-score of the three models ranged from 73.33% to 97.00%. The Kappa coefficient of all three models was >0.710. All models performed better than the first-year NM resident but not as well as the third-year NM resident in terms of diagnostic ability. However, the ResNet model provided “diagnostic assistance” to the NM residents. The models provided results at speeds 400 to 600 times faster than the NM residents.ConclusionDL-based models perform well in diagnostic assessment by thyroid scintigraphy. These models may serve as tools for NM residents in the diagnosis of Graves’ disease and subacute thyroiditis.  相似文献   
8.
目的 围绕足三里穴(ST36)进行文献可视化分析,探索近20年来有关足三里穴的研究进程、热点以及未来发展趋势。方法 以中国知网(CNKI)为数据来源,利用citespace软件对检索出的2000年1月至2021年11月收录的基础研究和临床研究文献分别进行可视化分析,绘制关键词、作者、机构相关图谱。结果 基础研究纳入1030篇文献,得到9个关键词聚类,电针中心度最高(0.53),发文量最多的作者是胡森(22篇),发文量最大的机构是北京中医药大学针灸推拿学院(23篇)。临床研究纳入2067篇文献,得到9个关键词聚类,穴位注射和针刺中心度最高(0.27),发文量最多的作者是张波(7篇),发文量最大的机构是浙江中医药大学附属第一医院(8篇)。结论 足三里穴在基础和临床的研究重点、热点和趋势不一致。并且在基础研究和临床研究之间,针刺镇痛、电针疗法、胃肠功能这三个内容是同步的,而关于代谢组学、穴位注射、温针灸和揿针的内容则是脱节的。  相似文献   
9.
There are limited data regarding intermediate-term outcomes in patients with persistent BK viremia. Other viral infections have been implicated in the development of allosensitization through heterologous immunity, but the relationship between BK viremia and donor-specific antibodies (DSAs) is unexplored. In 2008, we initiated routine post-transplant BK viremia and DSA screening at our center; 785 kidney or kidney–pancreas transplant recipients were included in our study. Of these recipients, 132 (17%) recipients developed BK viremia during the study period. The median duration of BK viremia was 140 days (interquartile range=40–393 days), and persistent BK viremia was defined as lasting ≥140 days. Kaplan–Meier curves were generated to assess differences in patient and allograft survival on the basis of BK viremia status; survival was modeled using Cox proportional hazard regression. After a median follow-up of 3 years, there was no significant difference in terms of patient (hazard ratio [HR], 0.83; 95% confidence interval [95% CI], 0.28 to 2.49) or allograft survival (HR, 0.80; 95% CI, 0.37 to 1.73) between patients with and without BK viremia, which was confirmed in a time-varying analysis. In our logistic regression model, persistent BK viremia was strongly associated with the development of class II (HR, 2.55; 95% CI, 1.30 to 4.98) but not class I (HR, 1.13; 95% CI, 0.46 to 2.77) DSAs. These data suggest that persistent BK viremia does not negatively affect intermediate-term patient or allograft survival but is associated with increased risk for de novo DSA, although the exact mechanism is unclear.  相似文献   
10.
International Urology and Nephrology - This article updates the qualitative research on Iran reported in the 2012 article by Tong et al. “The experiences of commercial kidney donors: thematic...  相似文献   
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