The 18S rDNA sequences of the six most common European Lymnaeidae species (Mollusca:Gastropoda:Basommatophora) have been obtained by direct PCR cycle sequencing and silver staining methods. The sequence alignment and secondary structures of the 18S rRNA gene of Lymnaea stagnalis, L. auricularia, L. peregra, L. palustris, L. glabra, and L. truncatula are analyzed. This gene proves to be a good m...

background: cercariae (larva of helminth parasites) are covered by a thick glycocalyx coat, which serves as an osmotic pro­tection during their free existence, and contain carbohydrates conjugated as glycoproteins, glycolipids and mu­co­polysaccharides. although, limited studies have been made on life cycle of cercariae from fresh water snails, however, car­bo­hydrate studies on cercariae have ...

cercarial dermatitis or swimmers’ itch is an itchy inflammatory response to the penetration of the skin by non-human schistosome parasites. in the hot season, may to september, in khuzestan province in the south west of iran, swimming in canals and agriculture activities in swampy areas are common. this survey was made on people from villages north of ahwaz city in south west iran, to estimate ...

Forgetting may allow an animal to react more appropriately to current conditions, rather than continuing to exhibit a previously learned, possibly maladaptive behaviour based on previous experience. One theory is that forgetting is an active process, whereby the previously learnt response is replaced by new learning that interferes with the older memory. Hence, we hypothesized that an appropria...

Evolutionary Aspects of Neuropeptides and their Genes Structure and evolution of insulin and insulin-like growth factors in chordates p. 15 Relationships among the FMRFamide-like peptides p. 25 Molecular evolution of neurohypophysial hormone precursors p. 39 A vasopressin-related peptide in the mollusc Lymnaea stagnalis: Peptide structure, prohormone organization, evolutionary and functional as...

Lymnaea cousini Jousseaume, 1887 was collected in Mucubaji, Merida State, Venezuela, from a permanent pond located at a very high altitude (3760 m). Identification of the collected specimens was made by comparison with the original description of the shell by Jousseaume and the description of the renal organ and reproductive system of topotypic specimens by Paraense.