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51.
Abstract

Background: Anti-inflammatory agents are widely used to relieve inflammation caused by various factors.

Aim: This study was initiated with the intention to deliver low aqueous soluble ketoprofen to enhance its solubility by developing microemulsion system as a template and then incorporating it into gel phase.

Materials and methods: Initially ketoprofen was solubilized into microemulsion preparation made up of clove oil, Tween 20 and propylene glycol as oil phase, surfactant and co-surfactant respectively, then it was incorporated into different concentration of gelling phase using gelling agents namely Carbopol 940, Carbopol 934 and hydroxypropyl methyl cellulose K4M (HPMC K4M). Formulated emulgels were evaluated for their physical appearance, pH, rheological properties, globule size, extrudability, drug content, spreadability, bioadhesion strength, in vitro and ex vivo drug release, skin irritation test and anti-inflammatory activity.

Results: Microemulsion had shown globule size 396?nm, pH 6–6.7, viscosity 29.4?cps and zeta potential ?12?mV indicating good stability. Formulated emulgels showed good physical appearance, skin acceptable pH 6–6.9, non-Newtonian shear thinning system, drug content 99.28?±?0.16%, bioadhesion strength 48.4 gram force, globule size 473?nm, spreadability 22.96?gm.cm/s, good extrudability, in vitro release, ex vivo release did not showed any irritation reaction and possess a good anti-inflammatory activity.

Conclusions: Selected batch showed enhanced drug release (92.42?±?4.66%) as compared to marketed gel (65.94?±?3.30). Similarly ex vivo release of formulation showed 72.22% release through mice skin compared with marketed gel. Formulations followed Korsmeyer–Peppas diffusion kinetic model. It was observed from the results that the formulated emulgel can provide promising delivery of ketoprofen.  相似文献   
52.
Interactions between host and gut microbiota in domestic pigs: a review   总被引:1,自引:0,他引:1  
ABSTRACT

It is well established that pig gut microbiota plays a critical role in maintaining metabolic homeostasis as well as in a myriad of physiological, neurological and immunological functions; including protection from pathogens and digestion of food materials – some of which would be otherwise indigestible by the pig. A rich and diverse gut microbial ecosystem (balanced microbiota) is the hallmark of good health; while qualitative and quantitative perturbations in the microbial composition can lead to development of various diseases. Alternatively, diseases caused by stressors or other factors have been shown to negatively impact the microbiota. This review focuses primarily on how commensal microorganisms in the gastrointestinal tract of pigs influence biochemical, physiological, immunological, and metabolic processes within the host animal.  相似文献   
53.
Herein, we focused on the one pot synthesis of ZnO nanoplates (NP edge thickness of ∼100 nm) using a chemical emulsion approach for chemical (direct) and electrochemical (indirect) determination of NO2. The structural and morphological elucidation of the as-synthesized ZnO NPs was carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-ray (EDAX), thermogravimetric analysis (TGA) and BET-surface area measurements. The XRD studies of the as-synthesised NPs reveal that ZnO NPs have a Wurtzite type crystal structure with a crystallite size of ∼100 nm. Such ZnO NPs were found to be highly sensitive to NO2 gas at an operating temperature of 200 °C. Electrocatalytic abilities of these ZnO NPs towards NO2/NO2 were verified through cyclic voltammetry (CV) and linear sweep voltammetry (LSV) using aqueous 1 mM NO2 (nitrite) in phosphate buffer (pH 7) solution. The results revealed enhanced activity at an onset potential of 0.60 V vs. RCE, achieved at a current density of 0.14 mA cm−2. These ZnO NPs show selective NO2 detection in the presence of other reactive species including CO, SO2, CH3OH and Cl2. These obtained results show that this chemical route is a low cost and promising method for ZnO NPs synthesis and recommend further exploration into its applicability towards tunable electrochemical as well as solid state gas sensing of other toxic gases.

Herein, we focused on the one pot synthesis of ZnO nanoplates (NP edge thickness of ∼100 nm) using a chemical emulsion approach for chemical (direct) and electrochemical (indirect) determination of NO2.   相似文献   
54.
55.
Proceedings of the National Academy of Sciences, India Section B: Biological Sciences - In-situ rainwater conservation improves chickpea productivity in Vertisols. This hypothesis was tested by...  相似文献   
56.
Summary 4-Methylphenylhydrazine hydrochloride was administered as 10 weekly subcutaneous injections of 140 g/g body weight and as 7 weekly intragastric instillations of 250 g/g body weight in physiological saline to randomly bred Swiss mice. Treatments given subcutaneously resulted in induction of lung tumors in incidences of 36% in females and 44% in males, while intragastric treatment caused a 40% incidence in females. In addition, it gave rise to blood vessel tumors by intragastric route in incidences of 32% in females and 18% in males. In the two physiological saline-treated control groups, the lung tumor incidence (combined) was 20% in females and 21% in males, while the blood vessel tumor incidence (combined) was 7% in females and 6% in males. Histopathologically, the lesions were classified as adenomas and adenocarcinomas of the lungs, and angiomas and angiosarcomas of blood vessels.4-Methylphenylhydrazine was postulated to be a metabolite of 4-hydroxymethylphenylhydrazine, an ingredient of the commonly eaten mushroom Agaricus bisporus. The implications are discussed with respect to the tumorigenesis data.This study was supported by Public Health Service Contract NOl CP33278 from the National Cancer Institute, NIH, USA  相似文献   
57.
58.

Purpose

The aim of the study was to assess the distribution of accessory foramina in the mandibular body with computed tomography (CT).

Materials and methods

The CT images of the mandibular body in 300 subjects (183 females and 117 males aged between 12 and 85 years) were retrospectively analysed for the presence of accessory foramina. The buccal and lingual surfaces were examined by dividing them into anterior and posterior quadrants.

Results

Of the 300 subjects, 26 presented with accessory foramina on buccal posterior aspect and 70 subjects presented on buccal anterior aspect. Further, on the lingual posterior aspect, 132 subjects presented with accessory foramina and 59 subjects presented on lingual anterior aspect. Most of the subjects with accessory foramina in the buccal posterior, buccal anterior and lingual anterior regions had accessory foramina on other aspects of the mandible as well.

Conclusion

A substantial number of subjects presented with accessory foramina on the lingual posterior aspect when compared to other aspects. Nevertheless, the number of subjects with accessory foramina on other aspects of the mandible was considerable and cannot be ignored. It is suggested that when an accessory foramen is identified in an individual on a particular aspect of the mandibular body, it is highly probable that he will exhibit accessory foramina on other aspects as well.  相似文献   
59.
Virus Genes - Citrus yellow mosaic badnavirus (CMBV) causes mosaic disease in all economically important citrus cultivars of India, with losses reaching up to 70%. CMBV belongs to the genus...  相似文献   
60.
Oral and Maxillofacial Surgery - To compare the intraoperative utility of bur and saw and to examine the pattern of lingual split during bilateral sagittal split osteotomy of mandible. This study...  相似文献   
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