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1.
以改性胺1618固化剂为囊芯、脲醛树脂为壁材单体,采用界面聚合技术,成功制备了一种新型聚脲改性胺微胶囊固化剂。通过正交设计试验,考察了芯壁质量比、乳化剂种类和质量分数及搅拌速率对微胶囊包覆率、粒径大小及分布情况的影响,并确定了最佳制备工艺条件。采用马尔文激光粒度仪、扫描电镜对微胶囊粒径大小、分布情况及表面形貌进行表征,采用热重分析仪及傅里叶变换红外光谱对其化学结构进行表征,通过拉伸试验对自修复材料的断裂力学性能进行研究。结果表明,该微胶囊含有固化剂芯材,其热稳定温度为198 °C,当芯壁质量比为0.7∶1、乳化剂为阿拉伯胶、乳化剂质量分数为1.5%、搅拌速率为800 r/min时,所制备的微胶囊包覆率达到79.8%,平均粒径为207.5 nm,呈规则的球形,分散性及表面致密性好。当基体材料中加入质量分数为1%的微胶囊后,拉伸强度提高64%,弹性模量提高287%。  相似文献   

2.
以脲醛树脂(UF)/壳聚糖(CS)复合材料为壳材,以溶解了阿维菌素的二甲苯为芯材,研究脲醛树脂(UF)/壳聚糖(CS)缓控释农药微胶囊的制备方法。改变壳层聚合过程中作为交联剂的甲醛的引入方式,制备得到一系列微胶囊。通过红外光谱仪、粒度分布仪、扫描电镜等对微胶囊的化学结构、组成成分、形貌特征进行表征,发现在缩聚阶段引入甲醛可以提高微胶囊壳层中壳聚糖的含量,进而提高微胶囊的包覆率和缓释效果。在优化条件下制备得到的微胶囊粒径7.14 μm,包覆率大于70%。  相似文献   

3.
采用重结晶的方法纯化并超细化酞菁蓝,得到粒径为200~500 nm的超细化酞菁蓝晶体。通过表面改性的方法提高了酞菁蓝在四氯乙烯中的悬浮性能,得到了稳定的酞菁蓝电泳液。以脲醛树脂为壁材,电泳液为囊芯,采用“一步法”原位聚合制备了蓝色电子墨水微胶囊。扫描电子显微镜(SEM)照片表明,制得的微胶囊粒径为30~50 μm,球形规整,表面光滑。研究了影响微胶囊制备的关键因素,最佳的微胶囊制备条件为:聚乙烯醇和尿素的质量比为0.20,反应时间为3~4 h,pH为3~4,搅拌速率为500~700 r/min。  相似文献   

4.
【目的】采用可生物降解壁材形成微胶囊,并研究其热化学性质。【方法】在乳液体系中,以聚酰胺为壁材,以界面聚合法制备了辣素同系物——N-香草基壬酰胺微胶囊,并依照微分方程法进行热重数据的处理。【结果】电镜与红外光谱显示了微胶囊的形成。根据比表面的表征结果为I类吸附曲线,假定了微胶囊为紧密堆积形式,求得了热分解活化能为8 755.3 J/mol。【结论】聚酰胺可以作为形成N-香草基壬酰胺微胶囊的壁材,其热分解反应最概然动力学模式函数符合三维扩散机理。  相似文献   

5.
锐孔-凝固浴法制备薏苡仁酯微胶囊的工艺研究   总被引:1,自引:0,他引:1  
目的探讨锐孔-凝固浴法制备薏苡仁酯微胶囊化的工艺条件,得出包埋率高、感官质量好的薏苡仁酯微胶囊产品。方法丙酮为溶剂提取薏苡仁酯;以海藻酸钠为壁材,锐孔一凝固浴法进行微胶囊化。结果正交实验得出微胶囊化最佳工艺条件:壁材海藻酸钠初始溶液的质量浓度为8g/L,芯材薏苡仁酯与壁材海藻酸钠的质量之比为0.6:1,乳化剂在壁材与芯材乳化分散液中的质量浓度为单甘酯0.5g/L及蔗糖酯0.5g/L,固化液CaCl2的质量浓度为10g/L。结论由此得到的微胶囊于室温下鼓风干燥,包埋率达80.4%,包埋效果好。  相似文献   

6.
采用界面聚合法,以甲苯2,4-二异氰酸酯和哌嗪为反应单体、30号相变石蜡为芯材,制得了一种智能纺织品用蓄热调温相变微胶囊。通过红外光谱、扫描电镜、差示扫描量热仪对微胶囊的化学组成、形貌和蓄热性能进行了表征,测试了其耐热和耐溶剂性。结果表明:所得微胶囊主要为球形,表面光滑,平均粒径为10.6μm,对w=0.40的NaOH溶液、w=0.60的H2SO4溶液、无水乙醇、丙酮稳定,能被甲苯、二甲基甲酰胺、乙醚破坏。相变潜热为118 J/g,石蜡在微胶囊中的质量分数为84%。  相似文献   

7.
氯氰菊酯微胶囊剂的制备   总被引:2,自引:0,他引:2  
目的:探讨以脲醛树脂为壁材,以氯氰菊酯为囊芯物制备聚脲微胶囊的工艺条件.方法:采用原位聚合法制备聚脲微胶囊,对比不同反应时间、搅拌速度、反应温度、催化剂对微囊化的影响.结果:通过实验得知,在反应温度60~70 ℃,搅拌速度3 000 r/min,以NH4Cl缓慢调节pH值为2.0左右,酸化时间2 h的反应条件下,可获得大小及分布理想的微囊颗粒.结论:氯氰菊酯聚脲微胶囊技术成功实现了农药由液态向固态的转变,使得药物的配制和施用更加方便、快捷,并为有害生物防治产品的多样化提供了可能.  相似文献   

8.
目的:拟考察以月见草油同姜黄素制备微胶囊的方法及其形状,并进一步的考察其对动脉粥样硬化模型大鼠的治疗效果。方法:首先以喷雾干燥的方式制备微胶囊,以姜黄素-月见草油及半合成脂肪酸甘油酯为芯材,并以明胶及β-环糊精为壁材,制备微胶囊。通过对微胶囊表征参数及溶出特性的测定后,确定其产品的稳定性,并进一步的考察其溶出度以及其对动脉粥样硬化模型大鼠的治疗效果。结果:根据之前设定的配方可设定配置产品的配方为:芯材∶壁材=1∶20,明胶∶β-环糊精=1∶1,姜黄素∶月见草油∶半合成脂肪酸甘油酯=1∶40∶2,最终可以获得形态稳定的微胶囊,微胶囊的粒径范围在2.7~8.8μm,平均粒径为6.2μm。经过计算,该微胶囊包埋率为28.8%,SEM结果显示,其颗粒稳定光滑无裂痕。根据红外光谱的结果可知,该微胶囊的芯材同壁材是通过物理键相结合的,同时,本微胶囊在模拟胃液中稳定,释放程度较低,而在模拟肠液中,其释放程度较高,而且可以达到缓释释放的目的。而制得的月见草-姜黄素微胶囊可以显著性的降低大鼠的血脂参数,经过12周的灌胃,大鼠的TG、TC、LDL-C及HDL-C水平均显著下降。HE染色显示,微胶囊组的血管同立普妥组类似,与模型组比较,内膜较光滑,平滑肌细胞排列较规则,炎性细胞浸润减少。结论:以月见草油同姜黄素制备的微胶囊稳定性及生物利用度均有所提高,并抑制了高脂饮食模型大鼠的动脉硬化形成,其机制可能与调节脂质代谢相关。  相似文献   

9.
通过原位聚合法,以密胺树脂(MF)为壁材,制备了微胶囊包覆聚磷酸铵(MCAPP),然后密炼将MCAPP与聚乳酸(PLA)熔融共混,得到微胶囊包覆聚磷酸铵阻燃聚乳酸,并研究了不同树脂包覆率的MCAPP对共混物形貌结构、加工性能、热性能、力学性能以及阻燃性能的影响。结果表明,在原位聚合过程中,当MF质量分数为17.2%时,MCAPP树脂包覆率可达13.2%,共混物中PLA结晶度提高,降解程度最低,同时阻燃效果最佳,极限氧指数可达39.4%,并且垂直燃烧等级达到UL94 V0级。  相似文献   

10.
目的:探讨杜仲叶提取物微胶囊化壁材选取及最佳配比工艺研究。方法:选用阿拉伯胶和β-环状糊精(1:1)做为杜仲叶提取物的微胶囊壁材,利用喷雾干燥进行微胶囊化。结果:阿拉伯胶和β-环状糊精(1:1)做为杜仲叶提取物的微胶囊壁材,微胶囊化能达到较好的效果,芯材与壁材的最佳配比为0.1g/g。  相似文献   

11.
Objective To observe blood pressure change with age in salt-sensitive teenagers whose salt sensitivity were determined by repeated testing.Methods Salt sensitivity was determined through intravenous infusion of normal saline combined with volume-depletion by oral diuretic furosemide in 55 teenagers. After five years, salt sensitivity was re-examined and subject blood pressure was followed up. Blood pressure changes in salt-sensitive teenagers were compared to that of non-salt sensitive teenagers over five years.Results After 5 years, the repetition rate of salt sensitivity determined by intravenous saline loading is 92.7%. In teenagers with salt sensitivity on the baseline, both the systolic blood pressure increments and increment rates were much higher than non-salt sensitive teenagers (12.7±12.1 mmHg vs. 2.8±5.2 mmHg, P< 0.01; 12.2%± 12.0% vs. 2.5% ±4.4%, P< 0.001,respectively). There was a similar trend for diastolic blood pressure (8.4 ± 6.4 mmHg vs. 3.7 ± 6.4 mmHg, P = 0.052; 13.2% ±10.6 % vs. 6.8%± 10.1%, P = 0.053, respectively).Conclusions Salt sensitivity determined by intravenous saline loading showed good reproducibility. Blood pressure increments with age were much higher in salt-sensitive teenagers than non-salt sensitive teenagers, especially in terms of systolic blood pressure.  相似文献   

12.
Objective: To evaluatel the value of D-dimers in patients with acute aortic dissection (AAD). Methods: This study consisted of 16 patients with AAD and 27 non-AAD patients. Serum D-dimets were measured by Sta-Liatest D-DI immunoturbidimetric assay. Results: D-dimer level was higher (P < 0.001) in patients with AAD(7.91 ± 5.52 μg/ml) than that in non- AAD group(1.57±1.24 μg/ml). D-dimer was positive (>0.4 μg/ml) in all patients with AAD and in 10 control group patients (37%). Among patients with acute AAD, D-dimers tended to be higher in Stanford A than in Stanford B (8.67 ± 4.31 μg/ml vs. 3.24±1.27 μg/ml, P <0.01). D-dimer values tended to be higher in more extended disease(3.84 ± 1.65 μg/ml, 8.57 ± 3.58 μg/ml and 11.87 ± 5.69 μg/ml in thoracic aorta, thoracic and abdominal aorta, thoracic and abdominal aorta and iliacal arteries, respectively, P < 0.05 for both 8.57 ± 3.58 and 11.87 ± 5.69 vs. 3.84 ± 1.65 ). Including the control group into the analysis, we found a sensitivity of 100%, a negative predictive value of 100%, and a specificity of 66% and a positive predictive value of 64% for D-dimer in diagnosis of AAD in our patients with suspected AAD. Conclusion: D-dimer was elevated in patients with AAD. A negative D-dimer test result could be useful in excluding AAD.  相似文献   

13.
Objective: To set up a simple and reliable rat model of combined liver-kidney transplantation. Methods: SD rats served as both donors and recipients. 4℃ sodium lactate Ringer's was infused from portal veins to donated livers,and from abdominal aorta to donated kidneys, respectively. Anastomosis of the portal vein and the inferior vena cava (IVC) inferior to the right kidney between the graft and the recipient was performed by a double cuff method, then the superior hepatic vena cava with suture. A patch of donated renal artery was anastomosed to the recipient abdominal aorta. The urethra and bile duct were reconstructed with a simple inside bracket. Results: Among 65 cases of combined liver-kidney transplantation, the success rate in the late 40 cases was 77.5%. The function of the grafted liver and kidney remained normal. Conclusion: This rat model of combined liver-kidney transplantation can be established in common laboratory conditions with high success rate and meet the needs of renal transplantation experiment.  相似文献   

14.
Increasing maternal age is the only etiological factor unequivocally linked to Down's syndrome in humans. The occurrence rate of newborns with Down's syndrome is about 1/220 in women over 35 years old. However, the occurrence rate in embryos fertilized in vitro, of the elder woman is unclear. Using FISH we screened the number of chromosome 21 in preimplanted embryos of 5 elderly women (average age, 38.4 years) to study the feasibility and necessity of screening trisomy 21 in embryos in patients over 35 years old at the in vitro fertilization (IVF) center.  相似文献   

15.
Real-time three-dimensional echocardiography (RT3DE)is a new ultrasound technique that enables dynamic threedimensional visualization and quantification of the heart in real time. Investigation of feasibility and methodology of RT3DE in determining left ventricular (LV) and right ventricular (RV) volumes, RT3DE was performed in 35 normal adults using Philips SONOS 7500 system with a 2-4 MHz matrix array transducer. The 60°×60° "pyramid" volume database was obtained and analyzed on a TomTec echo workstation. Both LV and RV volumes were calculated with four 3DE methods (i.e. apical 2, 4, 8, and 16-plane) through manually tracing ventricular endocardial borders in end diastole and end systole. Stroke volumes were then calculated. LV volume was also measured by 2DE Simpson's rule using GE VIVID 7 ultrasound machine.  相似文献   

16.
A clinical guideline for the therapeutic interventions of integrative medicine may be defined as a written document which states a series of recommendations on therapeutic interventions of integrative medicine for a special disease or condition. The guideline may provide assistance to medical professionals in making clinical decisions aimed at improving the clinical outcome of patients and reducing the costs of medical care(~'4~. Recommendations issued by a guideline should be based on the best available evidence in both Western and Chinese medicine. For fulfilling this purpose, the development of clinical guidelines for therapeutic interventions in the field of integrative medicine should follow scientific principles and undergo a rigorous processes.  相似文献   

17.
Objective:To probe into the influence of changes of ovarian hormones on the pathogenesis of the specific sub-type premenstrual syndrome(PMS)and reveal partial microcosmic mechanisms of adverse flow of liver-qi.Methods:Estradiol(E2)and progesterone(P)levels in serum were determined at different phases of menstrual cycle by radioimmunoassay.Results:In the group of PMS with adverse flow of liver-qi.the secretive peak value Of E2 and P at the follicular phase significantly decreased,and the secretive peak value at the luteal phase did not come into being.Conclusions:Low E2 and P secretive peak at the follicular phase and absence of secretive peak at the luteal phase is one of the microcosmic mechanisms of PMS with adverse flow of liver-qi.One of the pathophysiologic mechanisms of specific sub-type PMS is probably the continuous low level of E2and P.  相似文献   

18.
Journal of Nanjing Medical University (English Edition) JNMU, sponsored by Nanjing Medical University, was established in 1987. It is a bimonthly comprehensive English medical journal published locally and abroad.Since 2007, Journal of Nanjing Medical University (English Edition )was granted Elsevier the full publishing and distribution rights worldwide for the Electronic Edition, excluding the People's Republic of China.  相似文献   

19.
Objective To measure Derpl and Blot5 allergen levels in asthmatics' homes in Hongkong.Methods Seventy houses were enrolled for a mite indoor environment study. Dust samples were obtained from two sites of each patients' house: bed and floor. Derpl and Blot5 levels were quantified by a two-site monoclonal antibody-based ELISA technique.Results The levels of Derpl allergens found in bed (geometric mean (GM) 3.43 μg/g of dust; 95%CI, 1.89-4.96 μg/g)and on the floor (GM 1.12 μg/g of dust; 95%CI, 0.71-1.53 μg/g) indicated significant differences (P=0.005). However, the levels of Blot5 allergens found in bed (GM 19.00 μg/g of dust; 95%CI, 0.89-38.90 μg/g) and on the floor (GM 6.14 μg/g of dust; 95%CI, 0.40-11.90 μg/g) showed no statistically significant difference. In addition, in regards to the exposure index for Derpl and Blot5 allergens found in bed and on the floor, 17.6% in bed and 8.6% on the floor had levels of Blot5 ≥ 10 μg/g of dust, higher than those obtained for Derp1 (7.2% and 0% in bed and on the floor respectively, P< 0.05); higher percentages in bed and on the floor (25.0% and 35.7%) were observed for levels of Blot5 =0 μg/g of dust as compared with Derpl in bed and on the floor (4.3% and 14.5% respectively, P< 0.05).Conclusions Derpl and Blot5 are the major allergens found in this regional study, Blot5 is a more potent allergen in Hongkong, probably reflecting the high level of exposure to Blomia tropicalis (Bt). Bt and Dermatophagoides pteronyssinus (Dp) allergens should be included for precise diagnosis and effective immuno-therapeutic treatment of mite allergy in Hongkong.  相似文献   

20.
ANTI-PROLIFERATION EFFECT OF ORIDONIN ON HL-60 CELLS AND ITS MECHANISM   总被引:4,自引:0,他引:4  
Objcetive To investigate the anti-proliferation effect of oridonin on leukemic HL-60 cells and its mechanism. Methods HL-60 cells in vitro in culture medium were given different concentrations of oridonin. The inhibitory rate of cells were measured by microculture tetrazolium (MTT) assay, cell apoptotic rate was detected by flow cytometry (FCM), morphology of cell apoptosis was observed by hoechst 33258 fluorescence staining, and the activity of telomerase was detected using telomere repeat amplification protocol (TRAP) PCR-ELISA before and after apoptosis occurred. Results Oridonin could decrease telomerase activity, inhibit growth of HL-60 cells, and cause apoptosis significantly. The suppression was both in time- and dose-dependent manner. Marked morphological changes of cell apoptosis including condensation of chromatin and nuclear fragmentation were observed clearly by hoechst 33258 fluorescence staining especially after cells were treated 48-60 hours by oridonin. Conclusions Oridonin has apparent anti-proliferation and apoptotic effects on HL-60 cells in vitro, decreasing telomerase activity of HL-60 cells may be one of its most important mechanisms. These results will provide strong laboratory evidence of oridonin for clinical treatment of acute leukemia.  相似文献   

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