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141.
米非司酮固体脂质纳米粒的性状研究 总被引:2,自引:1,他引:2
制备并考察了米非司酮固体脂质纳米粒(SLN).结果表明,所得制品呈圆球状,粒径较均匀;x射线衍射分析表明SLN中米非司酮主要以无定形结构为主;差示扫描量热法结果表明,在较高药脂比时,SLN分散系中的药物仍以高分散状态存在. 相似文献
142.
Rui-mao ZHENG Chang-jiang ZOU Shi-gong ZHU Department of Physiology Pathophysiology Health Science Center Peking University Beijing China 《Acta pharmacologica Sinica》2004,25(3):266-270
INTRODUCTION Sharing characteristics of stress mediators[1], cen-tral interleukin-1β (IL-1β) is very important in cardio-vascular and behavioral responses to stressors[2-4]. Itcan induce similar hypertensive responses to stress viacardiovascular regulatory regions[5]. We observed pre-viously that central IL-1β mediated cardiovascular re-sponses to some stressful stimuli, such as conditionedfear stimuli and footshock[6]. Many stressful stimulimay increase IL-1β mRNA expression and … 相似文献
143.
三角叶风毛菊化学成分研究 总被引:6,自引:0,他引:6
目的:对广西产三角叶风毛菊进行了系统的成分研究.方法:采用柱层析进行了单体化合物的分离,并运用波谱学方法对所分得的化合物进行了结构鉴定.结果:自其地上部分分得8个化合物,通过光谱解析鉴定了其结构.结论:黄酮类化合物4个,分别为木樨草素(Luteolin,Ⅰ),槲皮素(Quercetin,Ⅱ),槲皮素-3-O-α-L-鼠李糖苷(Quercetin-3-O-α-L-rhamnopyranoside,Ⅲ),芦丁(Rutin,Ⅳ);三萜类化合物2个,分别羽扇豆醇乙酸酯(Lupeol acetate,Ⅴ)羽扇豆醇(Lupeol,Ⅵ);甾体类化合物2个,分别为β-谷甾醇(β-sitosterol,Ⅶ),胡萝卜苷(Daucosterol,Ⅷ).化合物Ⅰ-Ⅷ均为首次自该种植物分得. 相似文献
144.
145.
我国药品需求弹性的研究 总被引:4,自引:1,他引:4
目的定量研究药品需求量与人均可支配收入、人们的健康水平、药品广告投入、药品价格等因素间的相关性。方法以经济学理论为基础,采用经济计量学方法和Eviews软件构建药品需求函数模型。结果与结论随着人们生活水平的提高,药品需求量将显著上升,而药品价格的变化对药品需求影响较小。 相似文献
146.
目的:探讨Wnt3a通过Jumonji C结构域6( Jumonji C domain 6,JMJD6)的表观遗传修饰在神经病理性疼痛
中发挥作用的机制。方法:将SD大鼠分为4组:Sham组,慢性缩窄性损伤(chronic constriction injury,CCI)组,CCI+阴性慢病毒表达载体(LV-NC)组;CCI+慢病毒过表达载体(LV-JMJD6)组。构建SD大鼠坐骨神经CCI模型和JMJD6慢病毒
表达载体。CCI术后第3天通过鞘内导管给药,按照分组分别给予生理盐水和含慢病毒的试剂(病毒滴度1×108 TU/mL)
各20 μL。监测大鼠的机械缩足阈值(paw withdrawal mechanical threshold,PWMT)和热缩足潜伏期(paw withdrawal thermal latency,PWTL),并运用蛋白质印迹法检测脊髓水平Wnt3a及NR2B蛋白的表达变化,免疫共沉淀检测JMJD6与Wnt3a之间是否存在直接相互作用。结果:与Sham组相比,CCI术后各组大鼠的PWMT明显降低和PWTL明显缩短(P<0.05)。与CCI组和CCI+LV-NC组相比,CCI+LV-JMJD6组的PWMT在术后第10和14天明显升高,PWTL在术后第14
天明显延长(P<0.05)。CCI术后第14天,CCI组及CCI+LV-NC组Wnt3a和NR2B蛋白表达水平较Sham组明显升高,鞘内注
射慢病毒载体后, CCI+LV-JMJD6组的Wnt3a和NR2B蛋白表达水平较CCI+LV-NC组降低(P<0.05)。免疫共沉淀结果显示Wnt3a与JMJD6之间无直接相互作用。结论:Wnt3a参与调节神经病理性疼痛,其作用可能与JMJD6的表观遗传修饰相关,两者可能通过间接相互作用进行调节。 相似文献
147.
目的:研究50 Hz 3.6 mT不同处理时间的正弦交变电磁场(Sinusoidal electromagnetic field,SEMFs)对体外培养人脐带干细胞(Human umbilical cord stem cells,HUCSC)增殖与成骨性分化的影响。方法:体外分离培养HUCSC,传代后随机分为6组。用频率50 Hz,3.6 mT的SEMFs分别每天处理HUCSC 0.0(对照组)、 0.5、1.0、1.5、2.0 h和2.5 h,倒置相差显微镜观察细胞形态,MTT法测定细胞增殖,在磁场处理后的15 d 和17 d 分别用茜素红和vonkossa对钙化结节进行染色,在磁场处理后的第4天和第6天 PCR检测胶原Ⅰ(Collagen-Ⅰ)和骨形态发生蛋白(Bone morphogenetic protein-2,BMP-2)mRNA表达量的变化,在磁场处理后的10、12、14 d 和 16 d测定ALP活性。结果:1.0、1.5、2.0 h和2.5 h组促进HUCSC增殖;磁场处理后的7~9 d细胞出现钙化结节;在SEMFs处理后的第14天和第16天0.5 h组和1.0 h组碱性磷酸酶(Alkaline phosphatase,ALP)活性显著高于对照;SEMFs处理组能增加HUCSC钙化面积,其中尤以0.5 h和1.0 h最为明显;SEMFs能增加Collagen-Ⅰ和BMP-2 mRNA表达量,其中尤以0.5 h和1.0 h组作用最为明显。结论:50 Hz,3.6 mT 1.0、1.5、2.0 h和2.5 h促进HUCSC增殖,同时SEMFs组能促进体外培养HUCSC成骨性分化,尤以处理0.5 h和1.0 h促进成骨性分化最为明显。 相似文献
148.
Jun-Pei LI Tian-Yu CAO Xiao-Yuan ZHA Yun YU Zi-Heng TAN Zai-Hua CHENG Hua-Bo YING Wei ZHOU Lin-Juan ZHU Tao WANG Li-Shun LIU Hui-Hui BAO Xiao HUANG Xiao-Shu CHENG 《老年心脏病学杂志》2022,19(7):522
BACKGROUNDThe cardiovascular hazards of total homocysteine (tHcy) are long known. In addition, despite the acknowledgment on the importance of low ankle-brachial index (ABI) (< 0.9), borderline ABI (0.91-0.99) was once commonly overlooked. This study aims to explore the independent and joint effect of tHcy level and borderline ABI on all-cause death in hypertensive population.METHODSThis study included 10,538 participants from China H-type Hypertension Registry Study. ABI was described into two groups: normal ABI (1.00-1.40) and borderline ABI. tHcy level was also divided into two groups: < 15.02 and ≥ 15.02 μmo/L. Four groups were analyzed, using COX proportional hazard regression model, separately and pairwise to observe the independent and joint effect on all-cause death.RESULTSA total of 126 (1.2%) deaths were observed in the 1.7 years follow-up time. Borderline ABI has a higher predicted risk of death than normal ABI (HR = 1.87, 95%CI: 1.17-3.00) after adjusting for potential covariates. Compare with tHcy level < 15.02 μmo/L (low tHcy), those with tHcy ≥ 15.02 μmo/L (high tHcy) had higher risk to event outcome (HR = 1.99, 95% CI: 1.30-3.05). According to the cumulative hazard curve, group with borderline ABI and high tHcy level has significantly higher altitude and larger increasing rate over follow-up period compare to other groups. Among those with borderline ABI, participants with high tHcy had higher death risk than those with low tHcy, nevertheless, no significant different between borderline and normal ABI among those with low tHcy levels.CONCLUSIONSBorderline ABI and tHcy level both have independent predictive value on all-cause death. The combined group of borderline ABI and high tHcy has highest risk factor of outcomes, which suggested the mutual additive value of borderline ABI and tHcy. More attention should be given to the importance of borderline ABI in hypertensive population, especially with elevated tHcy level.Homocysteine (Hcy) is a sulfur-containing, non-proteinogenic amino acid synthesized through the transmethylation of amino acid methionine from one-carbon metabolism. Elevated plasma total homocysteine (tHcy) level is associated with endothelial dysfunction, increased blood coagulation, and metabolic disturbance, promoting cardiovascular diseases, stroke, and coronary artery disease.[1,2] Notably, patients with high Hcy levels and concomitant hypertension were suggested to be at particularly higher risk.[3] Moreover, increasing studies have explored a positive association between advanced Hcy level with all-cause mortality. According to a recent dose-response meta-analysis, for each 5-μmol/L increment of tHcy levels, the risk for all-cause mortality increased by 33.6%.[4]The ankle-brachial index (ABI) is an effective, well-established measure that is commonly used in the diagnosis of peripheral artery disease (PAD),[5] meanwhile was well studied as an important indicator of atherosclerosis and CVD events.[6] Although ankle-brachial index (ABI) ≤ 0.90 has been recognized as the threshold value for abnormal/low ABI, which was proven to increase the risk of all-cause mortality,[7] a study from the American Heart Association has suggested ABI between 0.91 and 1.00 should be considered as “borderline area” in terms of cardiovascular risks,[8] considering of prior probability and sensitivity of ABI calculation. Emerging studies have aimed to explore the predictive value of borderline ABI,[9-11] however, controversy remains because of limited and inconsistent data. The current study aimed to explore the individual and joint effect of borderline ABI and tHcy on all-cause mortality among hypertensive adults. Although ABI level ≤ 0.90 has been and is going to remain significant in clinical practice, we believe broader concern should be placed on borderline ABI, especially for its value in risk differentiation and identification. To the best of our knowledge, there are no similar previous studies. 相似文献
149.
目的:制备促黄体激素释放激素类似物(Luteinizing hormone-releasing hormone analogues,LHRHa)靶向紫杉醇脂质体(Paclitaxel liposomes,PTX-Lipo),研究其在体外增强紫杉醇(Paclitaxel,PTX)对卵巢癌A2780/DDP细胞的抑制作用。方法:采用薄膜超声法制备PTX-Lipo与LHRHa靶向紫杉醇脂质体(LHRHa-Paclitaxel liposomes,LHRHa-PTX-Lipo),用透射电镜考察脂质体形态;高效液相色谱法测定2种PTX-Lipo的包封率;激光共聚焦法通过卵巢癌A2780/DDP细胞对4-氟-7-硝基-2,1,3-苯并氧杂恶二唑荧光素的摄取检测来反映细胞对NBD-Lipo与NBD-LHRHa-Lipo的摄取情况;MTT法及细胞克隆形成实验检测LHRHa-PTX-Lipo体外对卵巢癌细胞的生长抑制情况。结果:制备LHRHa-PTX-Lipo的平均粒径123.4 nm,包封率在90%以上;A2780/DDP细胞对NBD-LHRHa-Lipo组的荧光摄取明显高于NBD-Lipo组;LHRHa-PTX-Lipo对A2780/DDP细胞的生长及克隆形成抑制明显高于PTX组及PTX-Lipo组(P<0.05)。结论:采用薄膜超声法制备的LHRHa-PTX-Lipo可使药物在靶部位聚集,增强药物对卵巢癌细胞的抑制作用。 相似文献
150.
肥胖相关脂肪性肝病的影响因素 总被引:1,自引:0,他引:1
随着饮食结构和生活方式的改变,肥胖症、嗜肝病毒感染和酒精滥用共同成为当代肝病的三大病因,肥胖症及其伴随的胰岛素抵抗直接参与非酒精性脂肪性肝病(NAFLD)及其重要类型脂肪性肝炎(NASH)的发病。全球尤其是亚太地区肥胖流行已成为近十年NAFLD患病率显著增加的主要原因,因此当前在很多国家,NAFLD已成为慢性肝病最常见原因。然而亚洲一些NAFLD患者通常并无肥胖,这可能与各种族间超重和肥胖的定义不同有关。另外,并非所有肥胖患者都并发脂肪肝。提示体内增多的脂肪对肝脏并非都有害,仅某些部位的脂质沉积易引起代谢紊乱和肝脏受损。 相似文献