Racemates increase the chances of crystallization by allowing molecular contacts to be formed in a greater number of ways. With the advent of protein synthesis, the production of protein racemates and racemic-protein crystallography are now possible. Curiously, racemic DNA crystallography had not been investigated despite the commercial availability of L- and D-deoxyribo-oligonucleotides. Here,...

two deoxyglucose (dg) derivatives, (α,β)-2-deoxy-2-amino(ethylcarbamate)-d-glucose (ecb-dg) and (α,β)-2-deoxy-2-amino(1,2-dihydroxypropyl)-d-glucose (dhp-dg), were synthesized and radiolabeled successfully with [99mtc(h2o)3(co)3]+ complex. [99mtc]-ecb-dg and [99mtc]-dhp-dg complexes were prepared (96% and 93% radiochemical purities respectively) by using 46 mci of na99mtco4 in 1 ml saline. radi...

Two deoxyglucose (DG) derivatives, (α,β)-2-deoxy-2-amino(ethylcarbamate)-D-glucose (ECB-DG) and (α,β)-2-deoxy-2-amino(1,2-dihydroxypropyl)-D-glucose (DHP-DG), were synthesized and radiolabeled successfully with [99mTc(H2O)3(CO)3]+ complex. [99mTc]-ECB-DG and [99mTc]-DHP-DG complexes were prepared (96% and 93% radiochemical purities respectively) by using 46 mCi of Na99mTcO4 in 1 mL saline. Radi...

as shiites we must know our imams. by understanding their deeds under different  conditions, we can modify our behavior to match theirs. by following their example we can be sure of the righteousness of our deeds and can promulgate their way of life in our social lives. among our imams, because of special period of time, imam ali and imam hossein (peace be upon them) are distinguished. their fo...

The thermodynamics of rightand left-handed helix formation by poly[d(G-C)].poly[d(G-C)] and by poly(dG-mSdC).poly(dG-msdC) were measured spectrophotometrically and calorimetrically. From the spectrophotometric measurements the thermal stabilities of the alternative helical conformations were evaluated as a function of counterion concentration. From the calorimetric measurements the enthalpies o...

Spectroscopic studies on solutions of poly(dG-m5dC) over a wide range of salt concentration are presented. Low salt solutions [( Na+]) less than 2 mM) of poly(dG-m5dC) produce circular dichroism (CD) spectra typical of the left-handed, Z form at high salt [( Na+] = 1.75 M). Solutions of poly(dG-m5dC) at intermediate salt concentrations, e.g., 142 mM, yield CD spectra characteristic of the right...