Biological switch

These compounds may find its use as biological switching molecules to study the role of p300 on transcription and for the development of therapeutics against cancer (Balasubramanyam et al., 2003). Another lead to the development of therapeutic... 

Since peptide hormones and neurotransmitters act as biological switches, evolutionary development has tended to lead to peptides which have a short duration of biological activity at target tissue and which are rapidly degraded In the biological milieu. 

Peptides are unstable Many are because they are biological switches or substrates, but they can easily be made stable. 

Although the system we have considered here is a relatively simple one involving a first-order reaction, it has revealed the existence of some fascinating and exotic phenomena. Such phenomena are not limited to catalytic reactions but arise in other nonisothermal systems, for example, in continuous-flow stirred tank reactors, and even in isothermal systems. Their common feature is that the performance curve describing the system has to exhibit an inflection. Such inflections have also been observed in a biological context, where they play the role of a biological switch, which is activated in response to particular stimuli. 

Presently, the on-line coupling of NPLC and GC via heart-cutting is an established procedure which has been used successfully for several bioanalytical applications. Obviously, dfrect analysis of aqueous samples is not possible by NPLC, and therefore, a solvent switch by a sample pretreatment step (e.g. liquid-liquid extraction or SPE) is always requfred when biological samples are analysed by NPLC-GC. 

T. Seki, K. Yamaji, Y. Orita, S. Moriguchi and A. Sliinoda, Simultaneous determination of uric acid and creatinine in biological fluids by column-switching liquid cliromatogra-phy with ulti aviolet detection , 7. Chromatogr. A 730 139-145 (1996). 

Zebiihr et al. (29) developed an automated system for determining PAHs, PCBs and PCDD/Fs by using an aminopropyl silica column coupled to a porous graphitic carbon column. This method gives five fractions, i.e. aliphatic and monoaromatic hydrocarbons, polycyclic aromatic hydrocarbons, PCBs with two or more ortho-chlorines, mono-ort/io PCBs, and non-ortho PCBs and PCDD/Fs. This method employed five switching valves and was successfully used with extracts of sediments, biological samples and electrostatic filter precipitates. 

One of the gixatest influences in Carson s life, next to her mother who was her lifelong companion, was her biology teacher at Pennsylvania College for Women. After a required course from Mary Scott Skmker, Carson switched her major from English to... 

This model was first introduced by Kauffman [kauff69] in a study of cellular differentiation in a biological system (binary sites were interpreted as elements of an ensemble of genes switching on and off according to some set of random rules). Since its original conception, however, related models have found wide application in an... 

Francis Harry Compton Crick (1916-2004) was born in Northampton, England, and began his scientific career as a physicist Following an interrup- I tion in his studies caused by World War . he switched to biology and received his Ph.D. in 1954 at Cambridge University. He then remained at Cambridge University as pro essor. He shared the 1962 Nobel Prize in medicine. 

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