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21.
Obesity is one of the most common and major health concerns worldwide. Weight management through dietary supplements with natural plant extracts has become the focus of current research. Sweet orange essential oil (SOEO) is a natural plant extract, with many bioactivities. In order to evaluate the weight loss effect of SOEO microcapsules and investigate the underlying mechanism, we fed high-fat diet-induced obese SD rats with SOEO microcapsules for 15 days and found that SOEO microcapsules reduced body weight gain by 41.4%, decreased total cholesterol level, alleviated liver and adipose tissue pathological alteration. The results of fluorescence quantitative PCR revealed that decreasing the expression of peroxisome proliferators-activated receptor-γ, upregulating of uncoupling protein 2, hormone sensitive lipase and carnitine palmitoyltransferase I, inhibiting the expression of acetyl-CoA carboxylase appear to be the mechanism of SOEO microcapsules to lose weight. This study suggests that SOEO microcapsule is a potential dietary supplement for weight loss.

Abbreviations: SOEO: sweet orange essential oil; TC: total cholesterol; TG: triglyceride; LDL-c: low-density lipoprotein cholesterol; HDL-c: high-density lipoprotein cholesterol; PPARα: peroxisome proliferators-activated receptor-α; PPARγ: peroxisome proliferators-activated receptor-γ; UCP2: uncoupling protein 2; HSL: hormone sensitive lipase; CPT1: carnitine palmitoyltransferase I; ACC: acetyl-CoA carboxylase; NPY: neuropeptide Y; LEP: leptin; INS: insulin; ALT: alanine aminotransferase; AST: aspartate aminotransferase.  相似文献   

22.
通过测定脉络丛细胞海藻酸盐微囊在大鼠脑内移植前及移植后的物理及生化性能变化,以探讨其应用于移植治疗神经系统疾病的可行性.用海藻酸盐多聚鸟氨酸微囊包裹猪脉络膜细胞,移植至大鼠黑质-纹状体通道,移植前、移植后4个月及6个月分别测定微囊的大小、形态及细胞的活力、分泌蛋白质及神经营养因子的能力、蛋白质组学的变化.脉络膜细胞微囊在移植前、后大小、细胞活力、蛋白质组学分析、分泌蛋白质及神经营养因子的能力无显著变化.海藻酸盐-多聚鸟氨酸CP微囊能有效地防止脉络膜细胞被受体免疫系统所攻击,使得它们能在大鼠的大脑存活6个月以上并不引起不良作用.  相似文献   
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By virtue of the biocompatibility and physical properties of hydrogel, picoliter‐sized hydrogel microcapsules have been considered to be a biometric signature containing several features similar to that of encapsulated single cells, including phenotype, viability, and intracellular content. To maximize the experimental potential of encapsulating cells in hydrogel microcapsules, a method that enables efficient hydrogel microcapsule purification from oil is necessary. Current methods based on centrifugation for the conventional stepwise rinsing of oil, are slow and laborious and decrease the monodispersity and yield of the recovered hydrogel microcapsules. To remedy these shortcomings we have developed a simple one‐step method to purify alginate microcapsules, containing a single live cell, from oil to aqueous phase. This method employs oil impregnation using a commercially available hydrophobic filter paper without multistep centrifugal purification and complicated microchannel networks. The oil‐suspended alginate microcapsules encapsulating single cells from mammalian cancer cell lines (MCF–7, HepG2, and U937) and microorganisms (Chlorella vulgaris) were successfully exchanged to cell culture media by quick (~10 min) depletion of the surrounding oil phase without coalescence of neighboring microcapsules. Cell proliferation and high integrity of the microcapsules were also demonstrated by long‐term incubation of microcapsules containing a single live cell. We expect that this method for the simple and rapid purification of encapsulated single‐cell microcapsules will attain widespread adoption, assisting cell biologists and clinicians in the development of single‐cell experiments.  相似文献   
25.
为了制备包埋率高、稳定性好的火麻仁油微胶囊,拓展其在食品领域的应用范围,以火麻仁油为芯材、单双脂肪酸甘油酯为乳化剂、酪蛋白酸钠为壁材、固体玉米糖浆为填充剂、柠檬酸钠为缓冲盐、抗坏血酸棕榈酸钠为抗氧化剂,通过喷雾干燥法制备60%载油率的火麻仁油微胶囊,以微胶囊包埋率为响应值,在单因素实验的基础上,以干物浓度、进风温度、出风温度为实验因素,采用Box-Behnken响应面分析法进行优化。随后通过扫描电镜观察火麻仁油微胶囊表面形态结构,以确定包埋效果。并利用油脂氧化分析仪检测火麻仁油微胶囊的氧化稳定性。研究确定微胶囊的最佳工艺条件为:干物浓度42%、进风温度168 ℃、出风温度74 ℃,在此条件下制备得到的火麻仁油微胶囊包埋率可达92.15%。通过扫描电镜观察到火麻仁油微胶囊表面圆滑无裂痕,表明火麻仁油微胶囊包埋效果比较理想。经油脂氧化分析仪测定,与对照组(火麻仁油)相比,试验组(火麻仁油微胶囊)的氧化诱导期时间较长,能够达到30 h以上,说明通过对火麻仁油进行微胶囊包埋可以较大程度地提高油脂的稳定性。研究结果为火麻仁油在食品工业领域的开发和应用提供了理论支持。  相似文献   
26.
Physical damage of animal cells in suspension culture, due to stirring and sparging, is coupled with complex metabolic responses. Nylon microcapsules, therefore, were used as a physical model to study the mechanisms of damage in a stirred bioreactor and in a bubble column. Microcapsule breaskage folowed first-order kinetices in all experiments Entrainment of bubbles into the liquid phase in the stirred bioreactor gave more microcapsule breakage. In the bubble column, the bubble bursting zone at gas-liquid interface was primarilu responsible for microcapsule breakage. The forces on the microcapsules were equivalent to an external pressure of approximately 4 x 10(4) N . m(-2), based on the critical microcapsule diameter for survival of 190 mum. A stable foam layer, however, was found to be effective in protecting microcapsules from damage. The microcapsule transport to the gas-liquid interface and entrainment into the foam phase was consistent with flotation by air bubbles. This result implies that additives and operation of bioreactors should be selected to minimize flotation of cells. (c) 1992 John Wiley & Sons, Inc.  相似文献   
27.
海藻酸钠微胶囊作为一种包埋系统,因其价廉、无毒、生物相容性好、可生物降解等优点而备受关注.海藻酸钠微胶囊制备的研究一直是微胶囊制备的重要组成部分.本文概述了近年来海藻酸钠微胶囊的研究进展,包括主要制备方法及其影响因素,包埋微生物以改善微生物的应用性能等方面,并展望了海藻酸钠微胶囊在工业微生物等领域的发展.  相似文献   
28.
5-FU壳聚糖-阿拉伯胶缓释微囊的制备工艺研究   总被引:3,自引:0,他引:3  
研究以壳聚糖和阿拉伯胶为基质材料,制备5-FU缓释微囊.以微囊的药物包封率为制备工艺优化指标,利用复凝聚法,通过L_9(3~4)正交实验得出微囊的最佳制备工艺条件.以最佳制备工艺条件制备的5-FU缓释微囊,所制微囊形态及稳定性较好.体外释放研究表明,微囊有良好的缓释效果.  相似文献   
29.
APA微囊微环境影响胚胎干细胞增殖分化的体外研究   总被引:2,自引:0,他引:2  
Wang XL  Wang W  Ma J  Guo X  Yu XJ  Qiu ZW  Ma XJ 《生理学报》2005,57(6):766-771
以小鼠胚胎T细胞(embryonic stem cell,ESC)为模型,在牛理条件F对ESC进行微囊化包封、培养,并利用免疫组织化学技术及RT-PCR方法检测其生长及未分化状态,以期建立微囊化ESC这一体外培养模型,同时明确海藻酸钠-聚赖氨酸-海藻酸钠(alginate-poly-lysine-alginate,APA)微囊微环境对ESC增殖及分化潜能的影响。结果表明:ESC能够在微囊(包括液化型及非液化型)或微球(海藻酸钙胶珠)内生长良好,但因生长环境存在差异,其表现的生长行为各具特征。比较其它类型,ESC在液化型APA微囊内的存活期限最长。经体外维持培养3周以上,仍能持续表达胚胎源未分化T细胞的标志性蛋白AP,SSEA-1及转录因子Oct-4。为进一步明确微囊内增殖的ESC是台仍具有多向分化的干细胞潜能,应用机械破囊法释放微囊内ESC团,并在体外进行定向诱导。经过近3周的条件诱导,其结果为:细胞团DTZ染色阳性:anti-insulin免疫荧光检测阳性;且特异性表达Pdx-1,Ins-1基因。上述结果证明:APA微囊为ESC维持未分化状态的增殖提供了特殊的微环境,APA微囊内所形成的ESC团仍具有多向分化的干细胞潜能。  相似文献   
30.
Cancer stem‐like cells (CSCs) are rare subpopulations of cancer cells. The development of three‐dimensional tissues abundant in CSCs is important to both the understanding and establishment of novel therapeutics targeting them. Here, we describe the fabrication of multicellular tumor spheroids (MTSs) abundant in CSCs by employing alginate microcapsules with spherical cavities templated by cell‐enclosing gelatin microparticles. Encapsulated human pancreatic cancer cell line PANC‐1 cells grew for 14 days until they filled the cavities. The percentage of cells expressing reported CSC markers CD24, CD44, and epithelial‐specific antigen (ESA), increased during this growth period. The percentage at 24 days of incubation, 22%, was 1.6 times higher than that of MTSs formed on a nonadherent surface in the same period of incubation. The MTSs in microcapsules could be cryopreserved in liquid nitrogen using a conventional method. No significant difference in the content of CSC marker‐expressing cells was detected at 3 days of incubation when thawed after cryopreservation for 2 weeks, compared with cells incubated without prior cryopreservation. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1071–1076, 2015  相似文献   
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