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171.
R. Bendayan J. A. Pieper R. B. Stewart G. J. Caranasos 《European journal of clinical pharmacology》1984,26(2):251-254
Summary The extent of propranolol protein binding was determined in three different age groups of healthy drug-free caucasian males. Volunteers selected for study were 6–15 years old, 25–36 years old and 68–76 years old. Ten milliliters of blood were obtained via venipuncture and collected in glass tubes from the subjects after an overnight fast. Binding determinations were performed by equilibrium dialysis using radiolabelled propranolol. Serum albumin and 1-acid glycoprotein concentrations were determined in all subjects by radial immunodiffusion. The results obtained showed wide intersubject variability in the binding ratio of propranolol and serum concentrations of 1-acid glycoprotein. Mean albumin serum concentration was found to be significantly lower in the elderly group as compared to the adult and pediatric groups (p<0.02). A positive correlation was found between the binding ratio of propranolol and the serum concentration of 1-acid glycoprotein in all the subjects (r=+0.66,p<0.005). No significant correlation was found between the binding ratio of propranolol and the serum concentration of albumin (r=–0.03,p<0.88). These data suggest that the extent of propranolol binding is influenced primarily by serum concentrations of 1-acid glycoprotein and not by differences in age. 相似文献
172.
目的 评估我国疾病预防控制体系建设相关政策文件效力和实施效果,为我国疾病预防控制体系政策制定建言献策。方法 通过国家卫生健康委员会官网、“北大法宝”检索系统以“疾病预防控制”、“疾控体系”、“疾控”为主要检索词检索2003—2022年中央、国家及各部委发布的政策文件,经筛选后最终纳入52项疾病预防控制相关政策。将政策效力划分为政策力度、政策措施、政策目标3个维度,用疾病预防控制支出表示政策效果,通过构建多元线性回归模型对环境型、供给型、需求型三种不同政策工具疾病预防控制体系建设政策实施效果进行回归分析。结果 2003—2022年,我国疾控体系建设相关政策数量与总体效力值呈现平稳波动,且具有明显的正相关关系,政策平均效力值呈M型稳定变化趋势,整体水平偏低; 政策措施得分最高,政策目标次之,政策力度得分最低。相较于其他两种政策工具,环境型政策工具使用频率最高,需求型政策工具使用频率最低; 环境型(Coef.=0.732,P=0.015)、供给型(Coef.=0.64,P=0.010)、需求型(Coef.=0.523,P=0.035)三种政策工具对政策实施效果均具有促进作用,滞后期保持在1~2年; 上一年度的疾控支出对下一年度的政策效果具有促进作用(Coef.=0.74,P=0.032)。结论 我国疾病预防控制政策效力不断提高主要源于政策颁布数量的累计效应; 不同政策工具使用过程中存在不平衡、不充分问题; 三类政策工具均对我国疾病预防控制体系政策实施效果起到一定影响,且环境型政策工具最优; 疾病预防控制相关支出会强化政策实施效果,推动疾控体系建设快速发展。 相似文献
173.
目的 探索青少年网络成瘾和睡眠时长在受校园欺凌与抑郁关系之间的中介作用,为青少年抑郁的预防干预提供依据。 方法 使用青少年健康相关危险行为问卷及CES - D抑郁量表,采用多阶段整群抽样法抽取徐州市4 190名青少年进行问卷调查。结果 在控制人口学等变量后,受校园欺凌、网络成瘾、睡眠时长对抑郁均有预测作用(r = 0.283,P<0.01;r = 0.331,P<0.01;r = - 0.184,P<0.01)。路径分析表明,网络成瘾在受校园欺凌和青少年抑郁之间起中介作用;网络成瘾和睡眠时长在受校园欺凌和青少年抑郁间起链式中介作用。结论 受校园欺凌不仅直接影响青少年抑郁,还通过网络成瘾和睡眠时长的链式中介作用间接影响青少年抑郁。可通过减少青少年网络使用和提高睡眠时长来降低受校园欺凌对青少年抑郁的影响。 相似文献
174.
Chiara Di Lorenzo Francesca Colombo Simone Biella Creina Stockley Patrizia Restani 《Nutrients》2021,13(1)
Polyphenols are a group of phytochemicals with potential health-promoting effects. They are classified as flavonoid (flavonols, flavanols, flavones, flavanones, isoflavones, and anthocyanins) and non-flavonoid molecules (phenolic acids, hydroxycinnamic acids, lignans, stilbenes, and tannins). Although an increasing number of trials have shown a correlation among polyphenol consumption and a reduction in risk factors for chronic diseases, discrepancies in explaining their positive effects have been found in terms of the bioavailability. In fact, polyphenols show a low bioavailability due to several factors: interaction with the food matrix, the metabolic processes mediated by the liver (phase I and II metabolism), intestine and microbiota. On the other hand, the biological activities of phenol compounds may be mediated by their metabolites, which are produced in vivo, and recent studies have confirmed that these molecules may have antioxidant and anti-phlogistic properties. This review discusses the studies performed in vivo, which consider the polyphenol bioavailability and their different food sources. Factors influencing the biological effects of the main classes of polyphenols are also considered. 相似文献
175.
Dragana Arsenijevic Bojana Stojanovic Jelena Milovanovic Aleksandar Arsenijevic Milos Simic Marija Pergal Igor Kodranov Olga Cvetkovic Danilo Vojvodic Elizabeta Ristanovic Dragan Manojlovic Marija Milovanovic Nebojsa Arsenijevic 《Nutrients》2021,13(3)
The main biologically active components of plants belonging to the genus Allium, responsible for their biological activities, including anti-inflammatory, antioxidant and immunomodulatory, are organosulfur compounds. The aim of this study was to synthetize the mixture of dipropyl polysulfides (DPPS) and to test their biological activity in acute hepatitis. C57BL/6 mice were administered orally with DPPS 6 h before intravenous injection of Concanavalin A (ConA). Liver inflammation, necrosis and hepatocytes apoptosis were determined by histological analyses. Cytokines in liver tissue were determined by ELISA, expression of adhesive molecules and enzymes by RT PCR, while liver mononuclear cells were analyzed by flow cytometry. DPPS pretreatment significantly attenuated liver inflammation and injury, as evidenced by biochemical and histopathological observations. In DPPS-pretreated mice, messenger RNA levels of adhesion molecules and NADPH oxidase complex were significantly reduced, while the expression of SOD enzymes was enhanced. DPPS pretreatment decreased protein level of inflammatory cytokines and increased percentage of T regulatory cells in the livers of ConA mice. DPPS showed hepatoprotective effects in ConA-induced hepatitis, characterized by attenuation of inflammation and affection of Th17/Treg balance in favor of T regulatory cells and implicating potential therapeutic usage of DPPS mixture in inflammatory liver diseases. 相似文献
176.
177.
《Health & place》2021
This study broadens contextual environments to include adults’ activity spaces—inside and outside the residential neighborhood—to examine how contextual exposures shape type 2 diabetes risk. We use novel longitudinal data from the Los Angeles Family and Neighborhood Survey, construct time-weighted exposure measures of adults’ social-structural and healthy resource environments, and execute random effects logistic models predicting the probability of being diabetic. Results indicate that residential and activity space exposures are independently associated with adult diabetes, and that residential and activity space healthy resources combine to influence diabetes risk in synergistic ways. Living in more socioeconomically advantaged neighborhoods reduces diabetes risk, particularly when spending time in activity spaces with greater access to recreational facilities. Moreover, healthier activity space environments may compensate for living in neighborhoods devoid of healthy food options to lessen diabetes risk. Adopting an activity space framework can inform multilevel interventions aimed at alleviating type 2 diabetes and other chronic ailments. 相似文献
178.
目的 选择高效安全价廉适宜基层医院应用推广的根除幽门螺杆菌 (Hp)的方案。观察二种三联疗法(洛赛克、克拉霉素、阿莫西林、简称LCA ;善胃得、替硝唑、阿莫西林、简称ZTA)抗Hp感染的疗效 ,并与对照组 (泰胃美、简称Tag;普瑞博思、简称Pre)作比较。方法 :对 165例确诊为Hp感染的胃炎及溃疡病者 ,随机分治疗组 83例 (A组 42例、B组 41例 )和对照组 82例 (A1 组 41例均为溃疡、B1 组 41例均为胃炎 )。A组用LCA方案共一周 ,B组用ZTA方案二周 ;A1 组用Tag四周 ,B1 组用Pre十天。除A1 组 1例B1 组 2例失访外 162例治疗后 6周作呼吸试验 ( 1 3C-UBT、部分1 4C -UBT)等以观察近期疗效 ;14 6例 (A组 40例B组 37例 ,A1 组 36例B1 年组 33例 )一年后作胃镜等复查 ,确定Hp根除率及评价远期疗效。结果 :近期Hp根除率治疗组 91.6% (A组 95 .2 %、B组 87.8% )比对照组 35 .4% (A1 组 40 .4%、B1 组 30 .8% )高 (P <0 .0 1) ;远期Hp根除率治疗组 81.8% (A组 85 .0 %、B组 78.4% )明显高于对照组 30 .4% (A1 组 33.3%、B1 组 2 7.3% ) (P <0 .0 1) ;溃疡组 ,治疗A组Hp根除率 82 .6% ,B组 76.5 %均明显高于A1组 33.3% (P <0 .0 1) ;溃疡愈合率治疗组 87.5 % (A组 91.3%、B组 82 .4% )明显高于对照组 5 2 .8% (P <0 .0 1) 相似文献
179.
180.
维甲酸对二乙基亚硝胺诱发大鼠肝癌的抑制作用 总被引:5,自引:0,他引:5
探讨维甲酸(RA)对二乙基亚硝胺(DENA)诱发大鼠肝癌发病过程的作用,从第11周开始,对DENA诱癌的Wistar大鼠隔日腹腔注射RA,每只动物连续给药10次,并设对照组,在诱癌满16周时,每组处死7只,观察比较各组大鼠肝脏形成的大于等于3mm和大于等于5mm的结节数和所见最大结节的体积,给药结束后大加其他措施直至死亡,计算生存时间,在给药前,结束时和给药后20d分别记录大鼠体重,实验发现,治疗组肝切面结节数显著小于对照组(P<0.05),结节体积也显著小于对照组(P<0.05),与对照组相比,治疗组的生存时间延长55.8%(P<0.05),但体重差异不明显,结果提示,RA可明显减轻DENA诱发大鼠肝硬化的程度,形成肝癌结节的数目的大小,并延缓其发展,而且可延长荷瘤大鼠的生存时间。 相似文献