The release of eggs and sperm into the environment for external fertilization is common (Giese & Kanatani 1987) and thought to be the ancestral mating strategy (Wray 1995). Most phyla have at least some species that release sperm into the environment (free spawning or spermcasting) and a majority have representatives that also release eggs (broadcast spawning) for external fertilization (Levita...

A novel approach which had foreground of industrialization, surface liquid spraying, was studied in this paper to prepare biodegradable polylactic-co-glycolic acid (PLGA) microspheres for controlled release drug delivery system. To compare with the normal methods, the microspheres prepared by this approach were characterized by particle size distribution and photograph of microscope. The relati...

Although the dorsal raphe nucleus (DRN) has long been linked to neural control of aggression, little is known about the regulatory influences of the DRN when an animal engages in either adaptive species-typical aggressive behavior or escalated aggression. Therefore it is important to explore which neurotransmitter inputs into the DRN determine the escalation of aggression in male mice. Previous...

An emerging hypothesis to explain the mechanism of heroin-induced positive reinforcement states that opiates inhibit gamma-aminobutyric acid (GABA)-ergic interneurons within the mesocorticolimbic dopamine (DA) system to disinhibit DA neurons. In support of this hypothesis, we report that the development of heroin self-administration (SA) behavior in drug-naive rats and the maintenance of SA beh...

II. Preparation of polyelectrolytic hydrogels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 1. Monomers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Polymer synt...

In this study, new antimicrobial hydrogels were prepared via reaction of functionalized-tragacanthgum (TG) biopolymer by quaternary ammonium functionalization of TG (QTG) with acrylic acid(AA). Characterization of the QTG hydrogels (QTG-AA) was carried out by FTIR,thermogravimetric analysis (TGA), and 1H NMR. Dynamic mechanical analysis, (DMA) wasconducted to characteriz...

today hydrogels are considered as the materials that are able to play important role in drug delivery systems. to design an effective hydrogel applicable network, mathematical modeling has a critical role. a successful drug delivery device relies not only on intelligent network design but also on accurate prior mathematical modeling of drug release profiles. in this study, the modeling of the i...

objective: in dental treatments, use of carriers for targeted antibiotic delivery would be optimal to efficiently decrease microbial count. in this study, gentamicin was loaded into polylactic co-glycolic acid (plga) microspheres and its release pattern was evaluated for 20 days.   methods: in this experimental study, plga microspheres loaded with gentamycin were produced by the w/o/w method. t...

the influence of various polymers on the release rate of lithium carbonate from matrix-type tablets was investigated in an attempt to formulate a sustained release solid dosage form. for this purpose, tablets containing 450 mg of lithium carbonate along with various amounts of carbopol 934p, 971p, 974p, pemulen and eudragit rlpo as retarding agents and inactive ingredients (e.g. pvp, avicel or ...

the objective of the study was to compare pharmacokinetic and pharmacodynamic parameters of gliclazide after administration of immediate (ir) and modified release (mr) tablets. the experiment included rats with both normoglyceamia and streptozocin (stz)-induced hyperglyceamia. several mr formulations were designed and in vitro drug release profile was assessed by a dissolution test. for the fur...