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991.
羟丙基-β-环糊精是β-环糊精的一种化学修饰性衍生物,对于水难溶性药物具有良好的包合增溶效果。现对其理化性质、静脉给药后的毒性、药动学和组织分布的研究概况进行综述,并简要介绍其在国内外制剂中的使用情况,同时围绕静脉给药,对实际应用泾丙基-β-环糊精时需考虑的一些问题进行较详细的概述。  相似文献   
992.
用分子轨道计算方法研究儿茶素对自由基的清除作用   总被引:11,自引:0,他引:11  
  相似文献   
993.
复方丹参胶囊质量控制标准研究   总被引:7,自引:0,他引:7  
采用 TLC法鉴别复方丹参胶囊中高原丹参、三七及冰片 ;利用薄层扫描法测定高原丹参中丹参酮 A的含量 :甲醇提取液点样 ,石油醚 -醋酸乙酯 -冰醋酸 ( 8∶ 2∶ 0 .5)展开两次 ,4 80 nm扫描法测定。 5批样品每粒胶囊均含丹参酮 A0 .4 59~ 0 .557mg。  相似文献   
994.
目的研究mi R-186靶向PIG11基因抑制胃癌细胞的侵袭。方法首先通过生物信息学方法分析,寻找与PIG11(TP53I11)结合的靶mi RNAs。分别构建mi R-186 mimics、点突变序列(Point mutation,PM)、空白载体(Scramble),转染胃癌MKN-28细胞。q RT-PCR检测mi R-186表达,Western blot检测PIG11表达,分析mi R-186表达和PIG11表达之间的相关性。Transwell检测转染前后各组胃癌MKN-28细胞侵袭能力变化。结果生物信息学发现12个mi RNAs可能是PIG11的潜在靶mi RNAs,其中mi R-186与PIG11结合特异性最好、稳定性最强;MKN-28-mi R-186 mimics细胞株中mi R-186表达增高,而PIG11表达下调,而MKN-28、MKN-28-mi R-Scramble、MKN-28-mi R-186-PM 3个细胞株中mi R-186表达水平较低,而PIG11表达水平较高。MKN-28-mi R-186 mimics侵袭细胞计数明显低于其他3组(P<0.05)。结论 mi R-186有可能靶向结合PIG11,下调其表达并抑制胃癌细胞的侵袭。  相似文献   
995.
指末节断离再植探讨   总被引:3,自引:0,他引:3  
刘锦成 《现代医药卫生》2002,18(12):1060-1060
目的:探讨基层医院无显微吻合技术指末节断离再植的成活率。方法:通过38例45指末节断离再植,采用静脉留置针头鞘多侧孔减压引流,进行临床资料分析探讨。结果:45指末节断离再植,成活37指占82.22%,失败8指占17.77%.结论:指末节断离再植,采用静脉留置针头鞘多侧孔减压引流,起血液循环架桥式的作用,人为建立血液循环,提高指末节断离再植成活率。  相似文献   
996.
997.
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   
998.
A new drug-targeting system for CD13+ tumors has been developed, based on ultrasound-sensitive nanobubbles (NBs) and cell-permeable peptides (CPPs). Here, the CPP-doxorubicin conjugate (CPP-DOX) was entrapped in the asparagine–glycine–arginine (NGR) peptide modified NB (CPP-DOX/NGR-NB) and the penetration of CPP-DOX was temporally masked; local ultrasound stimulation could trigger the CPP-DOX release from NB and activate its penetration. The CPP-DOX/NGR-NBs had particle sizes of about 200?nm and drug entrapment efficiency larger than 90%. In vitro release results showed that over 85% of the encapsulated DOX or CPP-DOX would release from NBs in the presence of ultrasound, while less than 1.5% of that (30?min) without ultrasound. Cell experiments showed the higher cellular CPP-DOX uptake of CPP-DOX/NGR-NB among the various NB formulations in Human fibrosarcoma cells (HT-1080, CD13+). The CPP-DOX/NGR-NB with ultrasound treatment exhibited an increased cytotoxic activity than the one without ultrasound. In nude mice xenograft of HT-1080 cells, CPP-DOX/NGR-NB with ultrasound showed a higher tumor inhibition effect (3.1% of T/C%, day 24), longer median survival time (50 days) and excellent body safety compared with the normal DOX injection group. These results indicate that the constructed vesicle would be a promising drug delivery system for specific cancer treatment.  相似文献   
999.
丹参和透明质酸钠注射液对骨性关节炎治疗作用的实验研究   总被引:22,自引:0,他引:22  
采取家兔膝关节制动方法建立骨性关节炎动物模型,用丹参注射液和透明质酸钠注射液关节腔内注射进行治疗,分别在制动后3、6、9周测量关节活动度,取关节软骨制成标本经光镜和透射电镜观察。结果显示,与单纯制动组比较,丹参治疗组和透明质酸钠治疗组的关节活动度明显改善,关节病变出现晚,程度轻,以早期最明显。表明丹参和透明质酸钠具有延缓和减轻关节退变的作用,对骨性关节炎早期有一定的治疗作用。  相似文献   
1000.
A new type of modified lignin, lignin-p-Boc, was obtained through reaction with di-tert-butyl dicarbonate (Boc2O) in aqueous media catalyzed by 4-dimethylaminopyridine (DMAP). Boc modification occurred regardless of type of lignin, was tunable, and proceeded well in recovering lignin at high purity from sodium lignosulfonate (a common byproduct from pulping industry; lignin content: 60%). Lignin-p-BOC was demonstrated as a potential reactive filler in green plastic and as a potential crosslinker in design of bioresorbable composite polymeric implants. Furthermore, the effect of the modification on breakdown rate of alkali lignin by microbes was investigated, and results showed that the modification substantially decreases the breakdown rate. The tunable Boc modification process was designed via a system thinking, including availability of raw lignin, economical/green modification, potentiality of drop-in-change to current thermoplastic processing, modification impact on microbial degradability/disposed environment at the end of use life; hence the holistic consideration makes this alternative method for upgrade of technical lignins very practical for future industrial application. Via “in-situ” forming “easily breakable covalent bonds” with existing thermopolymers inside, Lignin-p-BOCs are also promising to play an important role as both excellent binders via “random match” and reductants in transforming linear plastic waste into circular plastics.  相似文献   
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