a novel rice-husk-silica supported n-propyl bipyridinium chloride (rhprbpcl) has been prepared. due to the basicity of rhprbpcl, it was decided to evaluate its catalytic activity in the one-pot preparation of tetrahydrobenzo[b]pyran, dihydropyrano[3,2-c]chromene and dihydropyrano[4,3-b]pyran derivatives. the catalyst was characterized by ft-ir, sem and tga analyses. this methodology offers seve...

many species belonging to the scrophularia genus have been used since ancient times as folk remedies for many medical conditions such as scrofulas, scabies, tumors, eczema, psoriasis, inflammations. the aim of this study was to characterize the matrix metalloproteinases (mmps) inhibitor compounds of the scrophularia striata extract by bio-guide fractionation. the aerial parts of s. striata were...

poly-(alkylcyanoacrylate) ester particles have been used for the preparation of different formulations ranging from ophthalmic delivery systems to cancer chemotherapy carriers in clinic. the aim of this study was to prepare and characterize poly-(methyl ethyl cyanoacrylate) (pmeca) particles containing 5-aminosalicylic acid (5-asa). pmeca particles were prepared using the inverse emulsification...

aim : this study evaluated the association between serum endothelin- 1 level and symptoms, clinical examination, laboratory and cardio-respiratory parameters, in patients with cirrhosis compared to controls. background : cirrhosis is associated with significant portal, pulmonary and systemic vascular abnormities. recent studies have suggested that endothelin -1 may have a significant role in th...

in this research, nanoporous silica (sba-15) was physically functionalized using2-(2-nitrobenzylideneamino) guanidine compound. this functionalized sba-15 was utilized as a new sorbentfor separation and preconcentration of some lanthanide ions. inductively coupled plasma optical emissionspectrometry (icp-oes) was used as a detection technique. the preconcentration factor of the method is 100and...

abstract introduction: the mineral content of dentin increases with age and its primary structure is altered. these changes may have unknown effects on efficiency of adhesive systems. the aim of this study was to find the effect of aging on dentin bonding agents. methods and materials: fourty eight extracted human premolars were divided into 2 groups under 15 years old & 2 groups over 45 years ...

normal 0 false false false en-us x-none ar-sa background: the h-reflex is a useful electrophysiological procedure for evaluating the status of the peripheral nervous system, especially at the proximal segment of the peripheral nerve. the purpose of this study is to investigate the relation between triceps surae h-reflex and m- response latencies and thigh length in normal population, in order t...

the aim of this study was to investigate the hemagglutination properties of caprine herpesvirus-1(cphv-1) and their application for cphv-1 antigen detection and evaluation of the dynamics of postinfectious/vaccine antibody production. cphv-1 hemagglutination activity was proved only with mouseerythrocytes, pbs and saline solutions at 4°c and 22°c. in vaccinated animals, goats and bucks withresp...

this paper identifies characteristics of business cycles in iran, applying hodrick-prescott (hp) and band-pass (bp) filters. using seasonal and anual data for 1970-2003, it is found that oil income is the key driving factor of business cycles in the iranian economy. furthermore, it is indicated that iran's economy has experienced seven business cycles during this period, in which the econo...