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1.
This study deals with a series of operations to isolate the micro-cellulose from the palm tree spathe sheath by using a modified chemical method to take into account the low cost and the completion speed and its characterization using X-ray diffraction technique (XRD), infrared spectroscopy (FTIR) and scanning electron microscope coupled with element analyzer (SEM/EDX). The results showed that the extraction method succeeded in obtaining very pure microscopic fibers with a width of 2–10 μm with a crystallinity index equal to 79.21%, containing the two cellulose features Iβ and II, that, the conversion ratio of the first to the second was estimated at 32, 87%.  相似文献   
2.
The immobilization of p-amino salicylic acid (PASA) on periodic oxidized cellulose (O.C) as a biocompatible carrier was investigated. The immobilization of the PASA is based on Schiff's base formation between the amino group of PASA and the aldehyde group of O.C. The in vivo and in vitro release of p-amino salicylic acid was studied. Such a system may be useful for the sustained delivery of the drugs in the body, since O.C. itself is a biosoluble carrier.  相似文献   
3.
Objective:Evolving evidence of anti-inflammatory effects is observed in patients with rheumatoid arthritis or ulcerative colitis following periodic adsorptive granulocyte and monocyte (GM) apheresis with a column containing cellulose acetate (CA) beads as apheresis carriers. This study was undertaken to obtain insights into mechanisms of anti-inflammatory actions of adsorptive GM apheresis with CA beads. Methods:In a series of in-vitro experiments, we investigated the effects of plasma proteins and the leucocytes 2 integrin (CD18) on granulocyte adsorption to CA beads. Results:Granulocyte adsorption to CA beads required plasma IgG, the complement C3 and was inhibited by an antibody to leucocytes CD18. Further, hepatocyte growth factor (HGF) and interleukin-1 receptor antagonist (IL-1ra) which have strong anti-inflammatory actions were released by granulocytes that adhered to CA beads. Conclusions:Plasma IgG, C3 derived complement activation fragments and leucocytes CD18 are involved in granulocyte adhesion to CA beads and hence the release of HGF and IL-1ra.Received 27 October 2003; returned for revision 16 December 2003; accepted by M. J. Parnham 8 January 2004  相似文献   
4.
In this paper it is demonstrated how the optimum composition of a mixture for direct compression consisting of -lactose monohydrate, roller-dried -lactose and microcrystalline cellulose can be found using a systematic optimization technique. The experiments were chosen according to a simplex lattice design. The results of these experiments were used to fit a mathematical model, which then can predict the properties of all possible mixture compositions and enables a graphic representation of these properties in the form of contour plots. At a level of 4% the effect of three disintegrants (sodium starch glycolate, croscarmellose sodium and crospovidone) on the properties of the tablets compressed from these filler-binders, was evaluated by superimposing the contour plots of the different tablet responses. It was found that all the disintegrants used were effective in this combination of filler-binders. In order to evaluate drug dissolution rate an extra experiment with crospovidone as the disintegrant was performed, in which oxazepam was used as a test drug.  相似文献   
5.
Penicillin sensor was prepared by immobilizing penicillinase (Pcase) on H+-selective carboxylated poly (vinyl chloride) (PVC-COOH) membrane or cellulose filter membrane. The immobilization techniques are as follows. Pcase was immobilized with GTH on H+-selective PVC-COOH membrane or some amount of BSA was dropped on that membrane. Another method to make immobilization is to mix type I Pcase with GTH and drop on a cellulose filter membrane. According to immobilization techniques, there were some differences in response properties of enzyme electrodes, however, all electrodes responded to Pcase-resistant penicillin derivatives. Pcase immobilized on cellulose filter membrane with H+-selective PVC membrane eletrode was more stable and more sensitive to penicillinase-resistant penicillin derivatives than any other immobilization techniques.  相似文献   
6.
目的:建立一种快速、有效的血清铜蓝蛋白(CP)筛查方法。方法:醋酸纤维膜电泳分离血清CP,盐酸联苯胺显示法。结果:用此方法可明确检测出Wilson氏病患者血清中CP含量的变化。结论:醋酸纤维膜电泳检测血清CP是一种有效的血清CP筛查方法。  相似文献   
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Diltiazem hydrochloride-ethylcellulose microspheres were prepared by the water-in-oil emulsion-solvent evaporation technique. Small and spherical microspheres having a mean microsphere diameter in the range of 40-300 µm and entrapment efficiency of ~60-90% were obtained. Scanning electron micrographs of drug-loaded microspheres showed the presence of uniformly distributed small pores and absence of drug crystals on their surface, indicating simultaneous precipitation of drug and the polymer from the solvent during solvent evaporation. Differential scanning calorimetric analysis confirmed the absence of any drug-polymer interaction. The in vitro release profile could be altered significantly by changing various processing parameters to give a controlled release of drug from the microspheres. The stability studies of the drug-loaded microspheres showed that the drug was stable at storage temperatures, 5-55°C, for 12 weeks.  相似文献   
10.
One of the principles of Green chemistry is the usage of biomass instead of crude oil for the production of chemicals and chemical goods. Wood refers to the term biomass along with agricultural residues, energy crops, and the biogenic part of waste such as solid municipal waste, landfill, sewage gas and farming waste. Wood is mainly composed of cellulose, lignin and hemicelluloses. Cellulose is the main component of wood and lignin is the main by-product of cellulose extraction. Our green approach to both of these polymers resulted in creating a new process for hydrocellulose fiber production and a new sorbent for oil spills removal based on hydrolysis lignin. It is worth pointing out that our approach provides the use of two main wood components in the frame of “cradle to cradle” cycle (Fig. 1) that supports the circular economy concept for research and process development (Clark et al., 2016).  相似文献   
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