introduction: this study was done to determine the site of obstruction in lacrimal drainage system in asian patients suffering from epiphora and to determine the transit time taken for the tracer material to reach the lacrimal sac and the nasal cavity. methods:dacryoscintigraphy was performed using radionuclide technetium-99m pertechnetate (99mtc) in 34 patients suffering from unilateral or bil...

In order to understand more clearly what factors limit the reproductive success of primary cavity-nesting birds, it is important to examine and compare the nest-site characteristics of sympatric species in a variety of forest and woodland habitats. To add to the data already available on various woodpecker species in eastern and central North America, several nest-site and habitat characteristi...

In order to understand more clearly what factors limit the reproductive success of primary cavity-nesting birds, it is important to examine and compare the nest-site characteristics of sympatric species in a variety of forest and woodland habitats. To add to the data already available on various woodpecker species in eastern and central North America, several nest-site and habitat characteristi...

Dehaloperoxidase (DHP) from the annelid Amphitrite ornata is a catalytically active hemoglobin-peroxidase that possesses a unique internal binding cavity in the distal pocket above the heme. The previously published crystal structure of DHP shows 4-iodophenol bound internally. This led to the proposal that the internal binding site is the active site for phenol oxidation. However, the native su...

The residue phenylalanine 198 (Phe 198) is a prominent cause of the lower activity of human carbonic anhydrase III (HCA III) compared with HCA II and other isozymes which have leucine at this site. We report the crystal structures of HCA III and the site-directed mutant F198L HCA III, both at 2.1 A resolution, and the enhancement of catalytic activity by exogenous proton donors containing imida...

The coordination number of the catalytic zinc ion in alcohol dehydrogenase has been studied by integrated ab initio quantum-chemical and molecular mechanics geometry optimisations involving the whole enzyme. A four-coordinate active-site zinc ion is 100-200 kJ/mol more stable than a five-coordinate one, depending on the ligands. The only stable binding site for a fifth ligand at the zinc ion is...

Several antibiotics were evaluated in model infections produced in mice with each of two strains of Fusobacterium necrophorum. In one model, local abscesses occurred at the site of subcutaneous injection; in another intra-abdominal abscesses were produced when the organisms were injected into the peritoneal cavity. Treatment with effective antibiotics prevented the formation of abscesses or min...