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排序方式： 共有1165条查询结果，搜索用时 31 毫秒
31.
Simin Wei Yinghui Wang Zhishu Tang Hongbo Xu Zhe Wang Tian Yang Taiyan Zou 《RSC advances》2021,11(3):1411
Green synthesis of silver nanoparticles (AgNPs) by using the extracts of Chinese herbal medicines (CHMs) has attracted tremendous attention due to the potential synergistic effect between metal nanoparticles and capping agents. However, since CHMs are precious and expensive, finding other cheap and eco-friendly resources for biosynthesizing AgNPs with superior medicinal activites is necessary. Herbal medicine residues (HMRs) are the by-products of traditional Chinese herbal medicine after decoction and were identified to contain approximately 30–50% of medicinally active ingredients, which may be advantageous for green synthesis of medicinal AgNPs. Inspired by this, we present herein the preparation of AgNPs by reusing Bazheng Mixture residues and evaluate both biosynthesis parameters and bioactivities, where Bazheng Mixture is a famous Chinese patent medicine for relieving inflammation and pain, and allaying fever. The UV-visible spectrum and DLS analysis showed that the as-prepared AgNPs were sensitive to pH, material proportion and incubation time, but the yield was impervious to material proportion. TEM, HRTEM, SAED and DLS characterization found that AgNPs (pH 10.0; material proportion 1 : 1; 6 h) had a face-centered cubic (fcc) structure and spherical shape with an average size of 22.2 ± 0.5 nm covered by anions, and existed in monodispersed form with long term stability. The AgNPs displayed potent toxic effects against both cancer cell lines and pathogens, and superior antioxidant activity. The IC50 for HCT116, HepG2 and HeLa cell lines were 13.07, 19.67, and 26.18 μg mL−1, respectively. The MICs of AgNPs for E. coli and S. aureus were both 50.0 μg mL−1. The uptake analysis of AgNPs for both pathogens and cancer cell lines was performed to preliminarily illustrate the mechanism of toxic effects. These results confirm that HMRs could be a low-cost, nontoxic and eco-friendly resource for green synthesis of medicinal AgNPs, and also provide an alternative method for general recycling strategies of HMRs.A novel method for green synthesis of medicinal AgNPs has been developed by using the residues of Chinese herbal medicine. 相似文献
32.
5-Ethoxymethylfurfural (EMF) has been identified as a potential biofuel and fuel additive, for which the production from glucose (the most abundant and inexpensive monosaccharide) in a one-step process would be highly desirable. Here, the synthesis of sulfonic acid-functionalized porous coordination polymers (PCPs) and their application as catalysts for EMF synthesis are reported. PCP(Cr)-BA (PCP material with Cr3+ ions and H2BDC-SO3H linkers) and PCP(Cr)-NA (PCP material with Cr3+ ions and H2NDC(SO3H)2 linkers) materials containing both Cr3+ sites and Brønsted-acidic –SO3H sites were prepared. The morphology, pore structure, acidity, chemical composition, and thermal stability of the two functionalized PCP(Cr) catalysts were analyzed by systematic characterization. The catalysts featured a porous morphology and dual Cr3+ and –SO3H sites, which enabled the cascade conversion of glucose to EMF. PCP(Cr)-BA exhibited higher performance than PCP(Cr)-NA with an EMF yield of 23.1% in the conversion of glucose at 140 °C after 22 h in an ethanol/water system. In addition, the as-prepared catalyst exhibited a high stability in the current catalytic system for EMF production from glucose with a constant catalytic activity in a four-run recycling test without an intermediate regeneration step.The PCP(Cr)-BA catalysts featured porous morphology and dual Cr3+ and –SO3H sites, which enabled the cascade conversion of glucose to EMF. In addition, the as-prepared catalyst exhibited a high stability in the current catalytic system. 相似文献
33.
Farzad Hayati DVM PhD Seyed Mehdi Ghamsari DVM PhD Mohammad Mehdi Dehghan DVM PhD Hamid Taghipour DVM 《Wound repair and regeneration》2023,31(1):28-39
ATP is a crucial molecule for every energy-dependent process in cells. In ischemic tissues, ATP production declines, and it finally results in cell death. One of the most common strategies in burn wound management is saving the zone of ischemia. In the current study, Mg-ATP-containing nanoliposomes were formulated and studied in vitro and in vivo. The particle size of the vesicles was between 50 and 100 nm and the mean zeta potential was −4.05 ± 0.52 mV as evaluated by dynamic light scattering and Zeta sizer instrument, respectively. The encapsulation efficiency of ATP in the nanoliposomes was found to be 9.3%. The morphology and size of nanoliposomes were further studied by transmission electron microscopy. The standard MTT assay revealed no cytotoxicity of the nanoliposomes when tested on the rat fibroblast cells. Forty rats were randomly divided into four groups (N = 10 each). Burn wounds were created by burn comb model on the back of the rats and the zone of stasis in each group was treated every 12 h for 3 days by injecting them with the Mg-ATP-nanoliposomes. Control samples included empty nanoliposomes, unencapsulated Mg-ATP and the Krebs–Henseleit buffer. Laser Doppler flowmetry results revealed that blood perfusion in the zone of ischemia in rats treated with Mg-ATP-nanoliposomes was more than in the other groups (p < 0.05). Histopathology revealed saving zone of stasis by Mg-ATP-nanoliposomes. Findings obtained in this study demonstrated that the formulated Mg-ATP-nanoliposome has the potential to save the stasis zone in burn wounds. 相似文献
34.
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
35.
Michael S. Simon MD MPH Theresa A. Hastert PhD Ana Barac MD PhD Hailey R. Banack PhD Bette J. Caan DrPH Rowan T. Chlebowski MD PhD Randi Foraker PhD Gayane Hovsepyan BS Simin Liu MD MPH ScD Juhua Luo PhD JoAnn E. Manson MD DrPH Marian L. Neuhouser PhD RD Tochukwu M. Okwuosa DO Kathy Pan MD Lihong Qi PhD Julie J. Ruterbusch MS Aladdin H. Shadyab PhD Cynthia A. Thomson PhD RD Jean Wactawski-Wende PhD Nida Waheed MD MPH Jennifer L. Beebe-Dimmer PhD 《Cancer》2021,127(4):598-608
36.
37.
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 recom
38.
Simin D. Rezaei Joshua A. Hayward Sam Norden John Pedersen John Mills Anna C. Hearps Gilda Tachedjian 《Viruses》2021,13(3)
Heightened expression of human endogenous retrovirus (HERV) sequences has been associated with a range of malignancies, including prostate cancer, suggesting that they may serve as useful diagnostic or prognostic cancer biomarkers. We analysed the expression of HERV-K (Gag and Env/Np9 regions), HERV-E 4.1 (Pol and Env regions), HERV-H (Pol) and HERV-W (Gag) sequences in prostate cancer cells lines and normal prostate epithelial cells using qRT-PCR. HERV expression was also analysed in matched malignant and benign prostate tissue samples from men with prostate cancer (n = 27, median age 65.2 years (range 47–70)) and compared to prostate cancer-free male controls (n = 11). Prostate cancer epithelial cell lines exhibited a signature of HERV RNA overexpression, with all HERVs analysed, except HERV-E Pol, showing heightened expression in at least two, but more commonly all, cell lines analysed. Analysis of primary prostate material indicated increased expression of HERV-E Pol but decreased expression of HERV-E Env in both malignant and benign regions of the prostate in men with prostate cancer as compared to those without. Expression of HERV-K Gag was significantly higher in malignant regions of the prostate in men with prostate cancer as compared to matched benign regions and prostate cancer-free men (p < 0.001 for both), with 85.2% of prostate cancers donors showing malignancy-associated upregulation of HERV-K Gag RNA. HERV-K Gag protein was detected in 12/18 (66.7%) malignant tissues using immunohistochemistry, but only 1/18 (5.6%) benign tissue sections. Heightened expression of HERV-K Gag RNA and protein appears to be a sensitive and specific biomarker of prostate malignancy in this cohort of men with prostate carcinoma, supporting its potential utility as a non-invasive, adjunct clinical biomarker. 相似文献
39.
目的了解动机访谈对社区中老年慢性病患者自我效能和健康行为改变的效果,为社区中老年慢性病患者健康行为管理提供依据。方法采用澳大利亚和中国专家共同设计的美好生活俱乐部调查问卷,以随机整群抽样方法,对部分社区287名中老年人进行问卷调查,了解人口学资料、慢性病患病情况和健康相关指标,以及中老年人自我健康评价、心理压力测量、生活满意度量表、行为改变阶段评估。共回收有效问卷265份,有效率为92．3％。结果经过动机访谈干预后的慢性病患者自报症状、生活满意度得分高于干预前（F=8．527,7．697;P〈0．05）,心理压力量表、行为改变阶段得分低于干预前（F=229．483,91．613;P〈0．01）,在身体状况自评、功能状态和社会功能评价这两个指标中的得分均差异无统计学意义（F=0．222,2．084;P〉0．05）。经过干预后,认为自己的健康程度在比较好及以上的从102人上升到114人、生活满意度中等及以上的人数从255人增加到265人;心理压力高度危险的从5人降低至1人;行为改变阶段中,处于行动期的人数从1人增加到20人、处于准备期的人数从138人上升到215人。结论动机访谈技术能明显加强社区中老年慢性病患者自我效能,促进健康行为改变。但由于行为改变阶段的渐进、分阶段、螺旋式的复杂发展过程,有必要对社区中老年慢性病患者提供持续的动机访谈支持,巩固其行为改变的成果。 相似文献
40.
