Publications by authors named "Sandip K Roy"

This study introduces new methods of screening for and tuning chiral space and in so doing identifies a promising set of chiral ligands for asymmetric synthesis. The carbafructopyranosyl-1,2-diamine(s) and salens constructed therefrom are particularly compelling. It is shown that by removing the native anomeric effect in this ligand family, one can tune chiral ligand shape and improve chiral bias.

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Fracture neck femur is still regarded as unsolved fracture especially in non-union and in some vertical shear fracture (Powel's 3). Two types of osteotomies Mcmurry and Shanz valgus osteotomy are suggested, both have some disadvantages. In this context, a transcervical osteotomy has been studied.

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This is a study of 60 patients with mean age of 30 years having intra-articular fracture of distal humerus of type C (AO classification). We treated these fractures by open reduction and internal fixation through transolecranon approach. Mean duration of operative time with that of injury was 10 days.

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Sixty-two femoral shaft fractures in 60 patients treated by elastic intramedullary nailing with mean age of the patients being 9.2 years (range 5 years to 12 years) and average follow-up of 15 months (range 7 months to 60 months) are evaluated. Twenty-eight fractures were fixed with titanium elastic nail while 34 fractures were fixed with Enders nail.

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Displaced midclavicular fractures resulting in malunion with shortening and rotational deformity does not remodel in adults and incidence of non-union in displaced midshaft clavicular fractures is between 10-15% especially in those with an initial shortening of >20 mm.We have treated 10 patients of displaced middle-third clavicle fracture by open reduction and internal fixation with plate and screws and found it to be very effective in respect to rehabilitation, union and cosmesis.

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Site-directed spin labeling and EPR spectroscopy offer accurate, sensitive tools for the characterization of structure and function of macromolecules and their assemblies. A new rigid spin label, spirocyclohexyl nitroxide alpha-amino acid and its N-(9-fluorenylmethoxycarbonyl) derivative, have been synthesized, which exhibit slow enough spin-echo dephasing to permit accurate distance measurements by pulsed EPR spectroscopy at temperatures up to 125 K in 1:1 water/glycerol and at higher temperatures in matrices with higher glass transition temperatures. Distance measurements in the liquid nitrogen temperature range are less expensive than those that require liquid helium, which will greatly facilitate applications of pulsed EPR spectroscopy to the study of structure and conformation of peptides and proteins.

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Enediynes continue to fascinate scientists working in various domains because of their structural complexity and fascinating biological mode of action. They represent a masterpiece of nature's ingenuity. Besides the warhead which is the enediyne moiety, these molecules are equipped with a locking device, a delivery system and a chemical trigger for activation.

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The spontaneous activation of a nonaromatic enediynyl azide under ambient conditions has been demonstrated. The aromatic enediyne followed the expected cycloaddition with the alkene in the neighbouring arm to form a stable bridged bicyclic enediyne.

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Synthesis of a 9-membered azaenediyne has been achieved for the first time via intramolecular N-alkylation; the importance of proximity of the reacting centres via cobalt carbonyl complexation of the acetylenic moiety and not the activation of propargylic carbon has been demonstrated.

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This document has been prepared as a set of workshop material, which will be presented in the International Congress on Medical and Care Compunetics in June 2004 in Den Hague, The Netherlands. The workshop is divided into two parts and deals with the fundamentals of the bioavailability and bioequivalence studies. First part of the workshop deals with the pharmacokinetic principles, and the second part discusses the statistical approaches and the data analysis using the Statistical Analysis Software (SAS).

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