GTP hydrolysis, for the translocation of the mRNA chain and the tRNA molecules. Analysis of the three-dimensional structures of unbound ribosomal subunits from eubacteria (Figure 1A; Schluenzen et al., 2000; Wimberly et al., 2000; Harms et al., 2001) and archaea (Ban et al., 2000) as well as of the entire ribosome (Yusupov et al., 2001) clearly showed that the centers of the major ribosomal act...

introduction: numerous studies have investigated the prevalence, incidence and clinical manifestations of gastrointestinal stromal tumors (gists). however, little is known about gists in iran. this pioneer study focuses on description of 36 patients with gists in iran. methods: a database was created for 36 patients suffering from gist who were treated in loghman medical center and tehran cance...

Case Report To date, several studies of aneuploidy rate in spermatozoa from infertile men have been published. Most of them found an increase incidence of aneuploid spermatozoa in infertile patients compared with normal donors (Moosani et al, 1995; Finkelstein et al, 1998; McInnes et al, 1998; Pang et al, 1999; Rives et al, 1999; Vegetti et al, 2000). However, in other studies, no differences i...

The phytochemistry of the genus Piper is rich in terms of numbers of compounds discovered, but given the diversity of this genus and the intraspecific diversity of secondary metabolites in those species that have been examined, Piper chemistry has not been adequately investigated. The natural products chemistry that has been elucidated is well documented and has been the subject of extensive re...

Despite the appearance of bacterial strains resistant to all clinical antibiotics, including vancomycin (the ‘last resort’), development of new antimicrobial agents has slowed during recent decades. To aid design of new antibiotics, we must develop a detailed understanding of the mechanisms of antibiotic action and antibiotic resistance. Several classes of antibiotics target the ribosome and ri...

In AD, a significant synaptic loss ranging from 20% to 50% is reported. Biochemistry, elec‐ tron microscopy and immunocytochemistry have shown a decrease in synaptic density, presynaptic terminals, synaptic vesicle and synaptic protein markers in AD brains com‐ pared with the normal aged controls (Terry et al., 1991; Geula, 1998; Larson et al., 1999; Yao et al., 1999; Ashe, 2000; Baloyannis et ...