Search PubMed⌕ Search

Biomedical subjects

P Collins

Publications and source records attributed to P Collins.

At least 361 records · Page 20Linked to original sources
PubMed1979

Prospective evaluation of angiography in the diagnosis and management of patients suspected of having pancreatic cancer.

One hundred three patients suspected of having pancreatic cancer underwent celiac and superior mesenteric arteriography which was reported 'blind.' Final diagnosis, operative findings, and resectability of pancreatic cancers were correlated with angiography reports. Forty patients had pancreatic cancer. Thirty-seven of these underwent laparotomy, and 14 (37%) had resectable lesions. Sensitivity and specificity of arteriogrphy for pancreatic cancer were 72% (29/40) and 71% (45/63) respectively. Resectability was unrelated to the angiographic diagnosis. Nonresectability was related to an angiographic finding of definite tumor vessel (4/4), large-vessel encasement (14/7), and major venous pathology (8/11). Only the first of these was unique to pancreatic cancer. Hepatic metastases were detected in only six of 13 patients. Small-artery encasement, arterial occlusion, vessel displacement, and gallbladder distention were not indicators of diagnosis or extent of disease. Major anatomic anomaly of foregut vasulature was revealed in 25% of angiographic studies. Prior knowledge of such anomalies has important bearing on the operative approach to pancreatic resection. We conclude that angiography should be performed prior to laparotomy whenever a resectable pancreatic cancer is suspected from other investigations. When used prospectively, angiography is not a reliable diagnostic or prognostic tool for pancreatic cancer.

Adolescent↗
PubMed1979

New technique for servo-control of arterial oxygen tension in preterm infants.

Equipment has been developed for the servo-control of arterial oxygen tension in sick, newborn babies. Using an indwelling umbilical arterial oxygen electrode as sensor, the equipment successfully regulated the administration of oxygen to 12 newborn babies with respiratory distress syndrome, significantly improving the stability of arterial oxygen tension and lessening the duration of episodes of hypoxia and hyperoxia.

Arteries↗
PubMed1979

Treatment of experimental herpes simplex keratitis with acycloguanosine.

Acycloguanosine, a recently developed compound with high inhibitory activity against viruses belonging to the herpes group, has been evaluated in experimental herpes simplex keratitis in rabbits in comparison with trifluorothymidine and preparations of idoxuridine and vidarabine at present in clinical use. All compunds were used in the form of ophthalmic ointments which were applied 5 times a day at intervals of 2 hours. Treatment began on the third day of infection and was continued for 4 days. Complete cure was obtained with acycloguanosine and idoxurdine; trifluorothymidine and vidarabine were considerably less effective. Acycloguanosine was equally effective when given intravenously in the form of its sodium salt, and could be detected in the tear fluid in inhibitory concentrations when given by mouth. The compound was relatively free from toxicity.

Administration, Topical↗
PubMed1979

Finger tremor and extrapyramidal side effects of neuroleptic drugs.

Finger tremor and extrapyramidal side-effects (EPSEs) were measured in seven patients before and during neuroleptic drug treatment to assess the relationship between the onset of EPSEs and changes in finger tremor spectra. Tremor and EPSEs were also measured in twelve patients stabilized on neuroleptic drugs to determine whether tremor could provide a reliable index of the presence and severity of extrapyramidal system disturbance. A downward shift in peak tremor frequently was noted within 48 hours of starting neuroleptic drug therapy, usually before the onset of EPSEs, and a significant negative relationship between the severity of EPSEs and tremor frequency (but not tremor amplitude). The peak frequency of finger tremor is thus a sensitive index of extrapyramidal disturbance and might be of value in predicting which patients taking neuroleptic drugs need anti-parkinsonian therapy.

Antipsychotic Agents↗
PubMed1979

The ventricular surface of the subcommissural organ: a scanning and transmission electron microscopic study.

The subcommissural organ of the rat has been studied by a combination of light, scanning and transmission electron microscopy. Special attention has been paid to the appearance of the ventricular surface of the organ. The ependyma-derived cells on the surface of the organ are extremely long with a width which diminishes steadily from the base, where the nucleus is situated, to the ventricular surface. This results in a fan-shaped arrangement of cells, the cytoplasm of each cell reaching the surface of the ventricular system. The apical surface of the cell has small ciliated extensions 1-1.5 micrometers in diameter protruding into the ventricular lumen. With conspicuous rough endoplasmic reticulum and Golgi apparatus, and microtubules in profusion, the subcommissural organ cells possess the hallmarks of active secreting cells. The surface of the cells shows pinocytic vesicles-suggesting exchange of materials with the cerebrospinal fluid.

Animals↗
PubMed1978

The dependence of some strains of Mycobacterium avium on mycobactin for initial and subsequent growth.

This paper demonstrates that various degrees of mycobactin dependence exist within the M. avium group of mycobacteria and that this characteristic is not confined to M. paratuberculosis. The strains employed came from a wide range of animal species and all were virulent for chickens. Mycobactin dependence was observed in the M. avium serotypes 1, 2 and 3. The importance of employing a medium containing mycobactin for primary isolations observation may be of interest in relation to the primary isolation of other species of mycobacteria.

Animals↗
PubMed1978

Plasma membrane motility and proliferation of human glioma cells in agarose and monolayer cultures.

Human glioma cells, growing as spherical colonies in agarose gel, or as monolayers on glass or plastic, were studied with time-lapse cinematography and electron microscopy. The cells in the agarose cultured colonies often had ruffling-like membrane structures which were similar in for, although smaller in size, than those observed on monolayer cultured cells. The ruffling-like structures were more frequent at the periphery than in the central regions of the colonies which was in parallel to the proliferative pattern. In time-lapse cinematography it was seen that pinocytotic vacuoles were formed from ruffling membranes in the monolayer cultures. In the transmission electron microscope, such vacuoles were also found near the ruffling-like structures in the agarose cultured cells. In dense monolayer cultures, ruffling and associated pinocytosis were to a large extent transferred from the margin to the upper surface of the cells. This capacity may be an important property for the ability of the malignant cells to attain extreme high cell densities in monolayer cultures and to grow as colonies in agarose cultures. As has been previously shown, the normal counterpart of the gliomas, the glia cells, cannot grow to high densities; they do not ruffle on their upper cell surface and are unable to grow in suspension or agarose culture.

Autoradiography↗
PubMed1977

Relative potencies of anti-herpes compounds.

Assessment of the relative potencies of compounds that inhibit the multiplication of herpesvirus is rendered difficult by the fact that they have been investigated by different workers who were not using comparable test systems. The relative and absolute potencies of idoxuridine, cytarabine, vidarabine, trifluorothymidine, and ara-DAP have therefore been evaluated by plaque inhibition, plaque reduction, and yield reduction tests, the most satisfactory dose-response lines being obtained by plaque reduction. The results obtained for five strains of type 1 and five of type 2 herpesvirus indicated that cytarabine was the most active compound, followed by idoxuridine and trifluorothymidine; vidarabine and ara-DAP were found to be the least active compounds. From comparisons of ED50 values derived from the dose-response lines it was found that the greater sensitivity of type 1 strains reported in the literature could only be confirmed with idoxuridine, since considerable overlaps in type sensitivity were observed with the other compounds.

Antiviral Agents↗