PubMed Health⌕ Search

Biomedical subjects

T Walker

Publications and source records attributed to T Walker.

101 records · Page 6Linked to original sources

Plaque assay and replication of Tipula iridescent virus in Spodoptera frugiperda ovarian cells.

A plaque assay was developed for the study of Tipula iridescent virus (TIV) replication using a cell line derived from the fall army worm Spodoptera frugiperda (Sf9). Infection and plaque formation were monitored with time by phase contrast microscopy, video and fluorescent light microscopy. Structure of virions, viroplasmic centres and organelles of infected cells were examined by transmission electron microscopy (TEM). After 4 h postinfection, plaques were visibly detected within the cell monolayer by the presence of localized cell damage and production of numerous vesicular-like cytoplasmic structures. Quantitation of virions present per A260 unit of TIV preparation was determined by TEM. The number of visible plaques corresponded to virus concentration and 1 A260 produced approximately 10(5) plaques. DNA hybridization analysis revealed no gross differences in genomic DNA from TIV propagated in either Sf9 cells or wax moth Galleria mellonella larvae. These findings indicate that Sf9 is permissive for replication of TIV and superior by some parameters to other cell lines currently in use for the study of host cell/TIV interactions.

Animals↗

Using nurse practitioners in home care. A report of two pilot projects.

Currently, nurse practitioners are not being employed by home care agencies due to problems related to reimbursement by third party payors, physician reluctance, and scope of practice concerns. This research describes client conditions and advanced practice services that home care nurses have identified as useful for the delivery of quality care.

Attitude of Health Personnel↗

Endodontic working length determination--where does it end?

Obtaining a correct working length is critical to the success of endodontic therapy. Failure to identify this crucial measurement can result in untoward treatment outcomes, which may include increased patient discomfort, possible infection or cyst development, and extrusion or intra-canal medication into the periradicular tissue. This article reviews the classical and current terminology, philosophies, and techniques that are used at present to determine endodontic working length accurately, and describes their clinical application. Recent clinical advances such as the electronic apex locator, direct digital radiography, and the surgical operating microscope also are discussed.

Adult↗