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81.
骨质疏松症是临床常见病多发病。随着人口老龄化的进展,骨质疏松的患病率逐年增加。目前国内外主要应用药物(包括西药和中药)疗法,其研究开展的较早也较系统,已取得了较大的进展,药理学研究多局限于口服药物和注射药物的研究。近年来,伴随着透皮剂和离子导入等理化技术的发展,中药经皮给药治疗骨质疏松症已取得一定进展。就此方面对补肾药物经皮穴位给药治疗骨质疏松症的机理作一探讨。  相似文献   
82.
目的建立去卵巢大鼠模型,观察性激素水平改变对泪腺中IL-17A以及IL-1β、IL-6、TNF-α等炎症因子表达的影响。方法实验研究。健康雌性SD大鼠20只随机分为2组,实验组(10只)摘除大鼠双侧卵巢,对照组(10只)为未摘除卵巢的模拟手术组。术前及术后第1个月、第2个月、第3个月时2组均行泪液分泌试验(SIT)、角膜荧光染色检查进行眼表评估。于第3个月时放射免疫分析法分别检测2组大鼠血清雌二醇、睾酮含量,HE染色观察泪腺上皮细胞形态,免疫组化染色法、Western Blot法检测2组泪腺中IL-17A、IL-1β、IL-6、TNF-α的表达。2组性激素质量浓度比较、炎症因子A值表达比较均应用独立样本t检验。2组各时间点的SIT结果比较采用重复测量资料两因素方差分析。结果实验组大鼠去卵巢后第3个月时,体内雌二醇浓度低于对照组(t=-35.37,P<0.01),睾酮浓度低于对照组(t=-12.13,P<0.01)。2组各时期SIT检查未见泪液分泌减少、均未见角膜荧光染色。HE染色见实验组泪腺腺泡萎缩,排列紊乱,胞质内酶原颗粒明显减少。泪腺IL-17A表达量2组比较实验组高于对照组(免疫组化法:t=7.56,P<0.01;Western Blot法:t=20.90,P<0.01)。余各因子表达量实验组也均高于对照组(免疫组化法:IL-1β:t=13.71,P<0.01;IL-6:t=13.92,P<0.01;TNF-α:t=6.11,P<0.01。Western Blot法:IL-1β:t=16.93,P<0.01;IL-6:t=12.46,P<0.01;TNF-α:t=14.47,P<0.01)。结论大鼠去卵巢3个月时性激素水平降低,未见明显眼表损害。但泪腺中炎症因子IL-17A、IL-1β、IL-6、TNF-α的表达增加。  相似文献   
83.
作者设计并合成了9个Schiff碱型取代对羟基本甲醛缩r-氨基丁酸酯类化合物。并用美国NIH提出的“抗癫痫药物开发程序(ADD)对所合成的化合物进行抗惊厥活性筛选。结果表明化合物Ⅲf、Ⅲg、Ⅲh、Ⅲi具有不同程度的抗惊厥活性。  相似文献   
84.
85.
The polymer water-lubricated bearing is widely used in marine transmission systems, and the tribological properties can be improved by addition of inorganic nano-fillers. The aim of this study is to investigate the effect of SCFs and temperature on the water-lubricating properties of high-density polyethylene (HDPE) composites. HDPE composites reinforced by varying content of short carbon fibers (SCFs) were fabricated via twin-screw extrusion and injection molding techniques to study the hardness and surface wettability of those composites. The tribological properties under water-lubricated conditions were investigated through a pin-on-disk reciprocating tribometer under different temperatures. The results showed that the increase in hardness of HDPE composites reached maximum to 42.9% after adding 25 wt % SCFs. The contact angle also increased with the increase in SCFs content and reached a maximum of 95.2° as the amount of SCFs increased to 20 wt %. The incorporation of SCFs increased the wear resistance and lubricating property of HDPE composites at different temperatures. The HDPE composite containing 20 wt % SCFs showed the lowest friction coefficient of 0.076 at 40 °C, and the wear track depth reached a maximum of 36.3 mm at 60 °C. Based on the surface wetting property and wear analysis, potential effect mechanisms of fillers and temperature were discussed. The knowledge from this study is useful for designing the anti-wear water-lubricated polymer bearing.  相似文献   
86.
Zika virus (ZIKV) causes significant human diseases without specific therapy. Previously we found erythrosin B, an FDA-approved food additive, inhibited viral NS2B−NS3 interactions, leading to inhibition of ZIKV infection in cell culture. In this study, we performed pharmacokinetic and in vivo studies to demonstrate the efficacy of erythrosin B against ZIKV in 3D mini-brain organoid and mouse models. Our results showed that erythrosin B is very effective in abolishing ZIKV replication in the 3D organoid model. Although pharmacokinetics studies indicated that erythrosin B had a low absorption profile, mice challenged by a lethal dose of ZIKV showed a significantly improved survival rate upon oral administration of erythrosin B, compared to vehicle control. Limited structure−activity relationship studies indicated that most analogs of erythrosin B with modifications on the xanthene ring led to loss or reduction of inhibitory activities towards viral NS2B−NS3 interactions, protease activity and antiviral efficacy. In contrast, introducing chlorine substitutions on the isobenzofuran ring led to slightly increased activities, suggesting that the isobenzofuran ring is well tolerated for modifications. Cytotoxicity studies indicated that all derivatives are nontoxic to human cells. Overall, our studies demonstrated erythrosin B is an effective antiviral against ZIKV both in vitro and in vivo.KEY WORDS: Flavivirus, Zika virus, Dengue virus, Antiviral, Protease inhibitor, Erythrosin B  相似文献   
87.
Objectives:It is crucial to identify effective diagnostic biosignatures of tuberculosis (TB) to optimize its treatment. Herein, we conducted a systematic review to elucidate the diagnostic efficacy of long noncoding RNA (lncRNAs) as TB biomarkers.Methods:We searched Medline, Web of Science, Embase, Cochrane Library, CNKI, Wanfang, VIP, and China Biology Medicine disc databases up to February 18, 2020. These studies focusing on lncRNAs as diagnosis markers of TB were collected. STATA 12.0 and Meta-disc1.4 software were used to analyze the data extracted from eligible studies.Results:We included 8 articles with 1058 TB patients, and 1896 healthy controls in our study. The values of pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and diagnostic odds ratio were 0.63, 0.86, 4.48, 0.43, and 10.31, respectively. Additionally, we plotted the summary receiver operating characteristic curve to evaluate the diagnostic accuracy, and the area under the curve was 0.80.Conclusion:The present study is the first meta-analysis to assess the diagnostic accuracy of lncRNAs in TB patients. We found that lncRNAs might constitute potential biomarkers for the diagnosis of TB patients. More population-based high-quality research should be conducted to validate the efficacy lncRNAs in TB patients.  相似文献   
88.
目的探讨颈动脉内膜剥除术(CEA)在颈动脉狭窄患者中的治疗效果。方法回顾分析我院2009~2013年,12例颈动脉粥样硬化伴狭窄的患者,通过术前颈动脉B超、CTA检查明确诊断,探讨相关手术适应证、手术方法、术后处理及治疗效果。结果患者均治愈出院,无死亡病例,所有患者均在全麻下行CEA,5例放置颈动脉转流管,7例未放置;头晕及TIA症状明显改善者8例;5例术后出现高血压、头痛;3例术后6h发生切口渗血,1例术后朐闷不适,冠脉CTA提示左前降支病变狭窄(85%)。结论CEA在治疗颈动脉粥样硬化伴狭窄中效果良好,需严格把握适应证,做好围手术期准备,合理使用转流管。  相似文献   
89.
目的 合成化合物NO 1886 ,一种脂蛋白脂酶活化观察脂蛋白脂酶活化剂是否降低高脂 /高蔗糖饲料诱发的糖尿病新西兰兔的血浆葡萄糖并减轻其动脉粥样硬化。方法 给予高脂 /高蔗糖饲料升高新西兰兔血浆总胆固醇 ,甘油三酯和葡萄糖及降低高密度脂蛋白胆固醇而导致动脉粥样硬化。饲料中加入 1 0 %NO 1886进行治疗观察。分别在 0、4、8、12、16、2 0及 2 4wk从禁食过夜的兔耳静脉抽取血样测定葡萄糖和脂质水平。第 2 4周末 ,处死动物 ,分离主动脉 ,经苏丹Ⅳ染色固定脂质后 ,计算脂纹病变面积。结果 应用NO 1886后 ,实验动物血浆葡萄糖 ,总胆固醇和甘油三酯降低 ,高密度脂蛋白胆固醇增加。对动脉粥样硬化的发展具有抑制作用。结论 NO 1886不仅可改善脂质紊乱 ,而且可降低血浆葡萄糖 ,减轻糖尿病兔动脉粥样硬化  相似文献   
90.
1. Astragaloside IV is a component from the widely used traditional Chinese herb Astragalus membranaceus and its effect on rat aortic ring contraction and relaxation were investigated. 2. The aorta from male Sprague-Dawley rats was isolated in an organ bath and ring tension was recorded with or without endothelium. Cumulative effects of astragaloside IV on vessel contraction and relaxation were observed in the presence of various antagonists related to vessel activity. 3. Astragaloside IV showed concentration-dependent inhibition of vessel contraction induced by phenylephrine and potassium chloride. The amount of calcium released from intracellular stores sensitive to phenylephrine was also markedly reduced by astragaloside IV. There was dose-dependent vasorelaxation in endothelium-intact rings, which was partly inhibited by pre-incubation with nitric oxide (NO) synthase (NOS) Nomega-nitro-L-arginine methyl ester and guanylate cyclase inhibitor, 1H-[1,2,4] oxadiazolo [4,3-alpha] quinoxalin-1-one. Astragaloside IV also induced a significant increase in aortic tissue content of guanosine 3",5"-cyclic monophosphate (cGMP) both in vivo and in vitro. Endothelial NOS inhibitor Nomega-nitro-L-arginine prevented vasodilatation, whereas neuronal NOS inhibitor 7-nitroindazole did not show significant influence on the vessel relaxation of astragaloside IV. 4. In conclusion, astragaloside IV inhibited vessel contraction through blocking calcium influx and intracellular calcium release. The endothelium-dependent vessel dilation of astragaloside IV was attributed mainly to the endothelium-dependent NO-cGMP pathway.  相似文献   
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