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901.
Jhaveri SD Mauro JM Goldston HM Schauer CL Tender LM Trammell SA 《Chemical communications (Cambridge, England)》2003,(3):338-339
Apo-myoglobin, labeled with the environmentally sensitive redox probe RuII(NH3)4(1,10-phenanthroline-5-maleimide)2+, was immobilized onto gold electrodes modified with 11-mercaptoundecanoic acid and subsequently labeled with biotin; avidin binding to the immobilized biotin was specifically and quantitatively detected by a change in cyclic voltammetry of the co-immobilized probe. 相似文献
902.
903.
Oxidative folding is the concomitant formation of the native disulfide bonds and the native tertiary structure from the reduced and unfolded polypeptide. Of interest is the inherent conformational tendency (bias) present in the reduced polypeptide to dictate the formation of the full set of native disulfide bonds. Here, by application of a novel tool, we have been able to assess this "native conformational tendency" present in reduced and unfolded bovine pancreatic ribonuclease A (RNase A). The essence of this method lies in the ability of the oxidant [Pt(en)(2)Cl(2)](2+) (where "en" is ethylenediamine) to oxidize disulfide bonds under conditions in which both reduction and disulfide reshuffling, which are essential for rearranging non-native disulfide bonds, are extremely slow. When applied to RNase A, the method revealed little or no bias toward formation of the full native set of disulfide bonds in the fully reduced protein. 相似文献
904.
Robert W. Rand Harold D. Snow David G. Elliott Melvin Snyder 《Applied biochemistry and biotechnology》1981,6(4):265-272
Thermomagnetic Surgery is a unique technique that takes advantage of the phenomenon of hysteresis heating of a ferromagnetic
material to produce intense but controlled temperatures within solid organs or tumors to cause coagulation necrosis. By controlling
the power of the electromagnetic coil system, the degree of heating of the tumor can be controlled through temperature monitoring
that allows limitation of the area of destruction to the disease process and avoids damage to surrounding structures. If the
ferromagnetic material is delivered by the arterial route to the tumor or organ, there is an additional beneficial effect
of ischemic necrosis of the tissue and in time more concentration of the ferromagnetic particles. This new technique is applicable
to selected cases of human cancer because no ill effect has been shown to exposure of the electromagnetic field or the ferromagnetic
material in experimental animals. 相似文献
905.
R Jason Herr Paul F Vogt Harold Meckler Michael P Trova Steven R Schow Russell C Petter 《The Journal of organic chemistry》2002,67(1):188-193
To develop a novel route for the scaleable synthesis of the chiral xanthine CVT-124 (1, aka. BG9719), a method for the late stage pyrimidine ring closure of the nitrogen-protected endo 2-norbornenyl imidazole 3 was developed. The three-component coupling of benzylamine, 2-cyanoglycine ethyl ester (4), and methyl 5-norbornene-2-carboximidate hydrochloride (5) was demonstrated to achieve 3 in 23-46% isolated yields. The imidazole 3 was then elaborated to construct the N-benzyl xanthine 2 as a 1:1 mixture of exo and endo isomers, which were separable at this stage by chromatography. The nitrogen-protected endo xanthine 2 is a key intermediate in the synthesis of CVT-124. 相似文献
906.
907.
908.
909.
Lower bounds for the eigenvalues of negatively curved manifolds 总被引:1,自引:0,他引:1
910.
Harold Jones 《Journal of Molecular Spectroscopy》1978,70(2):279-287
Eleven transitions of the ν2 band of 15NH3 were measured by the technique of infrared-microwave two-photon spectroscopy using an isotopic CO2 laser and 20-mW microwave power. By combining these results with those of previous two-photon measurements and with Stark laser spectroscopy results, the spectroscopic constants of this band were calculated. Using the previously unknown coincidence between the R(18) 13CO2 laser line and the asQ(5,4) infrared transition, velocity tuned multiple-photon Lamb-dip signals were observed. Very intense double resonance signals were observed on the (5,4), (6,4), and (4,4) microwave transitions and the magnitude of these effects was compared to those observed previously in 14NH3. 相似文献