in more recent years, it has become increasingly recognized that r&d; (research and development) is a key driver of economic growth, a source of innovation and change, and as such stimulates improvements in productivity and economic competitiveness. it is closely associated with knowledge and flexibility, two factors that have gained new significance as a source of competitiveness in an increas...

Mouse thymocytes were used to compare mechanisms by which Vibrio cholerae and heat-labile Escherichia coli enterotoxins activate the adenylate cyclase-cyclic adenosine monophosphate (AMP) system. Both enterotoxins had their time-delayed increase in cyclic AMP neutralized by antisera to V. cholerae or E. coli enterotoxin, blocked by low concentrations of ganglioside G(M1), and destroyed by prior...

A cell suspension was prepared from immature rat ovaries by treatment with trypsin and collagenase. The isolated cells were capable of converting [8-14-C]adenine to cyclic [-14-C]AMP and the rate of this conversion was stimulated in vitro by luteinizing hormone and human chorionic gonadotropine, but not by prolactin, norepinephrine, dopamine or albumin. The accumulation of progesterone was al...

â â â â â â â  this paper proposes a new forecasting model for investigating relationship between the price of crude oil, as an important energy source and gdp of the us, as the largest oil consumer, and the uk, as the oil producer. gmdh neural network and mlff neural network approaches, which are both non-linear models, are employed to forecast gdp responses to the oil price changes. the resul...

Cycl AMP concentrations were elevated and acrosome reactions were induced in intact sea urchin spermatozoa by Nigericin, A23187, and pH 9.0 seawater. To determine whether or not the metabolism of cyclic AMP was being altered in sperm heads, the heads were mechanically separated from the flagella, and the flagella-less heads were then isolated by differential centrifugation. The isolated heads c...

Using AMP deaminase (AMP aminohydrolase; EC 3.5.4.6) purified from rabbit left-ventricular heart tissue, we report direct investigation of the potential for cardiac AMP deaminase activity to be regulated by kinase-mediated phosphorylation. Rabbit heart AMP deaminase served as a substrate for Ca2+/phospholipid-dependent protein kinase (protein kinase C; PKC) exclusively; no other mammalian prote...

mon cause of fungal disease in humans. This fungus is known as the fourth leading cause of nosocomial infections. Over the last few decades, incidence of candidal infections due to C. albicans has been increasing, paralleling the growing numbers of immune-compromised patients. To the patients, disseminated candidiasis is sometimes a serious disease which often results in death. In addition, the...