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1.
目的 观察硬脂酸纳米吗啡(SLN-M)单次注入大鼠硬膜外腔后的镇痛效应.方法 选择硬膜外置管后无神经损伤症状的SD雄性大鼠50只,随机均分为五组.A组(假给药组):经硬膜外腔给予硬脂酸纳米(SLN);B1组与B2组:分别给予0.2及1 mg普通吗啡;C1组与C2组:分别给予含0.2及1 mg吗啡的SLN-M.用药后测定热痛阈值评价镇痛效果,以最大镇痛效应(MPE)表示,以SpO2、角膜反射的变化、僵直症的发生率对药物不良反应进行评估.结果 B1与C1组及B2与C2组的MPE最高值差异无统计学意义.但随时间延长,B1与B2组MPE逐渐下降,12 h后开始显著低于C1与C2组(P<0.05).B1与B2组达到MPE最高值的时间显著快于C1与C2组(P<0.05),但持续时间显著缩短(P<0.05).B1与B2组SpO2显著低于C1与C2组(P<0.05),角膜反射的变化和僵直症的发生率要高于C1与C2组(P<0.05),且与吗啡剂量呈正相关.结论 硬膜外腔单次给予SLN-M后可达到与普通吗啡一样的镇痛效果,有效镇痛时间明显延长,不良反应显著降低. 相似文献
2.
目的介绍近年来胰岛素纳米粒制剂研究进展。方法查阅国内外胰岛素纳米粒的相关文献资料,从吸收机制、制备、检测方法及其发展等方面进行整理和归纳。结果与结论目前胰岛素纳米粒的研究已广泛开展,取得了令人瞩目的成就,发展空间广阔。 相似文献
3.
Nilam H. Patil 《Drug delivery》2016,23(2):429-436
AbstractAlginic acid nanoparticles (NPs) containing insulin, with nicotinamide as permeation enhancer were developed for sublingual delivery. The lower concentration of proteolytic enzymes, lower thickness and enhanced retention due to bioadhesive property, were relied on for enhanced insulin absorption. Insulin-loaded NPs were prepared by mild and aqueous based nanoprecipitation process. NPs were negatively charged and had a mean size of ~200?nm with low dispersity index. Insulin loading capacities of >95% suggested a high association of insulin with alginic acid. Fourier Transform Infra-Red Spectroscopy (FTIR) spectra and DSC (Differential Scanning Calorimetry) thermogram of insulin-loaded NPs revealed the association of insulin with alginic acid. Circular dichroism (CD) spectra confirmed conformational stability, while HPLC analysis confirmed chemical stability of insulin in the NPs. Sublingually delivered NPs with nicotinamide exhibited high pharmacological availability (>100%) and bioavailability (>80%) at a dose of 5?IU/kg. The high absolute pharmacological availability of 20.2% and bioavailability of 24.1% in comparison with subcutaneous injection at 1?IU/kg, in the streptozotocin-induced diabetic rat model, suggest the insulin-loaded alginic acid NPs as a promising sublingual delivery system of insulin. 相似文献
4.
《Expert opinion on drug delivery》2013,10(7):889-905
Introduction: With the advancement in the field of medical colloids and interfacial sciences, the life expectancy has been greatly improved. In addition, changes in the human lifestyle resulted in development of various organic and functional disorders. Central nervous system (CNS) disorders are most prevalent and increasing among population worldwide. The neurological disorders are multi-systemic and difficult to treat as portal entry to brain is restricted on account of its anatomical and physiological barrier. Areas covered: The present review discusses the limitations to CNS drug delivery, and the various approaches to bypass the blood brain barrier (BBB), focusing on the potential use of solid lipid nanoparticles (SLN) for drug targeting to brain. The methods currently in use for SLN production, physicochemical characterization and critical issues related to the formulation development suitable for targeting brain are also discussed. Expert opinion: The potential advantages of the use of SLN over polymeric nanoparticles are due to their lower cytotoxicity, higher drug loading capacity and scalability. In addition, their production is cost effective and the systems provide a drug release in a controlled manner up to several weeks. Drug targeting potential of SLN can be enhanced by attaching ligands to their surface. 相似文献
5.
本研究在水热条件下利用羧甲基壳聚糖分别还原硝酸银和硫酸铜,得到稳定的羧甲基壳聚糖复合纳米银和纳米氧化铜,并测试其抑菌能力.表征测试显示,所制的纳米银为20~30 nm的球状结构,纳米氧化铜为80~100 nm的花瓣状结构,二者都均匀稳定地分布于羧甲基壳聚糖中.抑菌试验显示,不同浓度的羧甲基壳聚糖复合纳米银(A组2 mg... 相似文献
6.
Robert A. Kehoe MD 《Archives of environmental & occupational health》2013,68(4):236-239
The satisfactory quality of the practice of occupational medicine in industry is essential to the safety and health of employees. Measures of environmental control are not, in themselves, a satisfactory means of protecting workmen against many common hazards of industrial operations. Careful surveillance of workmen by trained, experienced, and competent occupational physicians is essential in the prevention of illness and disability induced by occupational operations, materials, and types of energy. The professional responsibilities of the occupational physician extend beyond the industrial facility into the general environment where the escaping production materials, by-products, and wastes may penetrate, and also into the larger community where its products may be distributed. The gross inadequacy in the number of trained physicians in the professional field must be met before this urgent problem of national health can be solved. 相似文献
7.
《Journal of microencapsulation》2013,30(8):693-702
In this study, pCAGG-ChIL2 plasmid DNA containing the chicken interleukin-2 (ChIL-2) gene was used to prepare DNA–chitosan nanoparticles (CNPs). The CNPs prepared were spherical, with mean diameters between 100 and 200?nm, have a positive surface charge, and could protect DNA against DNase I degradation. The CNPs prepared were successfully used to transfect the Df-1 cell line with almost no cytotoxicity. CNPs prepared at an amino group to phosphate group ratio (N/P ratio) of 16 provided the highest transfection efficiency (1.1%) in medium with a pH of 6.5. When pCAGG-ChIL2 CNPs were administered to chickens simultaneously with a DNA vaccine against Newcastle disease virus (NDV), haemagglutination inhibition antibody titers and serum interferon-γ (IFN-γ) levels were significantly higher than in chickens immunised with the NDV DNA vaccine alone (p?<?0.05). The results demonstrate that pCAGG-ChIL2 CNPs improve DNA vaccine-elicited immunity against NDV challenge. 相似文献
8.
《Expert opinion on biological therapy》2013,13(5):745-758
Insufficient contact of inherently highly active nucleic acid delivery systems with target cells is a primary reason for their often observed limited efficacy. Physical methods of targeting can overcome this limitation and reduce the risk of undesired side effects due to non-target site delivery. The authors and others have developed a novel means of physical targeting, exploiting magnetic force acting on nucleic acid vectors associated with magnetic particles in order to mediate the rapid contact of vectors with target cells. Here, the principles of magnetic drug and nucleic acid delivery are reviewed, and the facts and potentials of the technique for research and therapeutic applications are discussed. Magnetically enhanced nucleic acid delivery – magnetofection – is universally applicable to viral and non-viral vectors, is extraordinarily rapid, simple and yields saturation level transfection at low dose in vitro. The method is useful for site-specific vector targeting in vivo. Exploiting the full potential of the technique requires an interdisciplinary research effort in magnetic field physics, magnetic particle chemistry, pharmaceutical formulation and medical application. 相似文献
9.
目的 研制快速定量检测人血清胃蛋白酶原Ⅰ (pepsinogens Ⅰ,PGⅠ)试纸,并评价试纸性能.方法 以包裹有时间分辨荧光的纳米微球作为标记示踪物,运用免疫层析试纸技术,研制PG Ⅰ检测试纸;考察试纸的检测线性、灵敏度、精密度、与对比试剂的符合率.结果 试纸定量检测的线性良好,方程为Y=0.027 9+0.004 8X,r=0.997 8;灵敏度为0.27 μg/L;批内CV小于10%,批间CV11.03%;与市售PG Ⅰ试剂平行检测489份血清样本,有良好的相关性(YTRFIA =0.856 6Xstrip+7.545 6,R2 =0.989 1,P<0.01).结论 PG Ⅰ时间分辨荧光纳米微球免疫层析试纸操作简单、快速、经济、可定量,满足临床检测血清PG Ⅰ的需求. 相似文献
10.
目的 观察表阿霉素聚氰基丙烯酸正丁酯磁性纳米粒(EPI-PBCA-MNPS)对裸鼠移植性肝癌的作用效果.方法 建立Bel-7402裸鼠人肝癌模型,当肿瘤体积长至20~30mm3时,将其随机分成5组:生理盐水组(NS组)、表阿霉素组(EPI组)、表阿霉素聚氰基丙烯酸正丁酯纳米粒组(EPI-PBCA-NPS组)、表阿霉素聚氰基丙烯酸正丁酯磁性纳米粒组(EPI-PBCA-MNPS组)、表阿霉素聚氰基丙烯酸正丁酯磁性纳米粒组加磁场组(EPI-PBCA-MNPS+MF组),每组10只,除生理盐水组外,其余各组按照0.002mg/g体质量或相当于40 μg/只的表阿霉素静脉注射给药,治疗2周后处死裸鼠,准确测量肿瘤大小并称重,计算瘤体积抑制率及瘤重抑制率,所有肿瘤均编号病理切片,比较治疗前后各组肿瘤细胞坏死的程度.结果 治疗后肿瘤体积抑制率、瘤重抑制率除EPI-PBCA-NPS组与EPI-PBCA-MNPS组差异无统计学意义(P>0.05)外,其余各组间差异有统计学意义(P<0.05),其中EPI-PBCA-MNP+MF组(94.26%、80.82%)显著高于其余组,差异有统计学意义(P<0.01).病理切片显示,EPI-PBCA-MNP+MF组肿瘤细胞坏死程度最重.结论 EPI-PBCA-MNPS具有良好的靶向性,在外加磁场作用下对裸鼠人肝癌模型有显著抑瘤作用.Abstract: Objective To observe the effect of epirubicin polybutylcyanoacrylate magnetic nanoparticles (EPI-PBCA-MNPS) on the transplanted hepatoma in nude mice.Methods Human hepatoma cell line Bel-7402 nude mice models were established and divided into 5 groups with each of 10 once gross tumor volume was up to 20-30 mm3:normal saline group (NS),epirubicin group (EPI),epirubicin polybutylcyanoacrylate nanoparticles group (EPI-PBCA-NPS),epirubicin polybutylcyanoacrylate magnetic nanoparticles group (EPI-PBCA-MNPS) and epirubicin polybutylcyanoacrylate magnetic nanoparticles+magnetic field group(EPI-PBCA-MNPS+MF).Except for NS group, the dosage of epirubicin was 0.002 mg/g body weight or 40 μg for intravenous injection.After two-weeks therapy,all nude mice models were executed and the tumor volume and weight were measured so as to calculate the volume inhibition ratio and the weight inhibition ratio.Every tumor specimen was made into pathological section and labelled with serial number for comparing neorobiosis degree in different groups before and after therapy.Results There were statistically difference among the other groups (P<0.05) in the volume inhibition ratio and the weight inhibition ratio after therapy except for EPI-PBCA-NPS and EPI-PBCA-MNPS group (P>0.05).The two ratios in the EPI-PBCA-MNP+MF group (94.26%,80.82%) were significantly more than those in other groups (P<0.01).The pathological sections demonstrated the most severe tumour neorobiosis in the EPI-PBCA-MNP+MF group.Conclusion With the additional magnetic field,EPI-PBCA-MNPS has significant anticancer effect on human hepatoma nude mice models due to its favourable magnetic targeting. 相似文献