Search PubMed⌕ Search

Biomedical subjects

J Valentine

Publications and source records attributed to J Valentine.

50 records · Page 3Linked to original sources
PubMed1984

Focused hyperthermia with a magnetic resonance imaging (MRI) unit and an interstitial grounded probe.

The feasibility of using a commercial magnetic resonance imaging (MRI) scanner to do either imaging or hyperthermic treatment was demonstrated. Radiofrequency (RF) induced focal heating of phantoms and animal tissues was performed using a MRI scanner as the RF power source and a grounded interstitial probe as a device to produce hyperthermia via eddy current convergence. In the therapeutic mode, a pulse width of 900 microseconds and interval of 50 ms were used to give 2% duty cycle (closest simulation to continuous wave (CW) mode without bypassing imaging filters). Temperature in the vicinity of the grounded probe was measured with a field nonperturbing fluoroptic probe. Temperatures increased 4.5 degrees C in 5 minutes in a dielectrically uniform phantom, 3.1 degrees C in 6.7 minutes in rats' leg muscles, and 5.0 degrees C in 6.0 minutes in rats' peritoneum. The MRI of the phantom with the grounded probe and the fluoroptic probe was obtained using spin echo sequences. The potential advantage of this approach is visualization of deep-seated tumors and hyperthermic treatment with minimal modification of the MRI scanner.

Animals↗
PubMed1983

Follow-up of attempted suicide in Christchurch.

Ninety-eight subjects who had attempted suicide and 102 general practice controls previously interviewed were followed-up at 18-24 months. The former continued to show greater social and psychiatric disability than controls and more than one-third made repeat suicide attempts. Nevertheless, as a group, the attempted suicides showed significant improvement in mental state, and familial and interpersonal relationships, whereas controls reported little change in most measures. Persistence of suicidal ideation and repeat attempts were correlated with the diagnosis of psychosis and personality disorder and predictions about the likelihood of further suicidal activity were accurate. Although 92% of patients were referred for further treatment, 38% of these were judged to have dropped out prematurely. Completion of treatment and being in ongoing treatment were positively correlated with patients' self reports of improvement. The findings are compared to experience elsewhere and to a previous Christchurch follow-up study.

Follow-Up Studies↗
PubMed1982

A cytochrome c methyltransferase from Crithidia oncopelti.

The mitochondrial cytochrome c-557 of Crithidia oncopelti contains two lysine residues and an N-terminal proline residue that are methylated in vivo by the methyl group of methionine. The purified cytochrome can act as a methyl acceptor for a methyltransferase activity in the cell extract that uses S-adenosylmethionine as methyl donor. Crithidia cytochrome c-557 is by far the best substrate for this methyltransferase of those tested, in spite of the fact that methylation sites are already almost fully occupied. The radioactive uptake of [14C]methyl groups from S-adenosylmethionine occurred only at a lysine residue (-8) and the N-terminal proline residue. This methyltransferase appears to differ from that of Neurospora and yeast [Durban, Nochumson, Kim, Paik & Chan (1978) J. Biol. Chem. 253, 1427-1435; DiMaria, Polastro, DeLange, Kim & Paik (1979) J. Biol. Chem. 254, 4645-4652] in that lysine-72 of horse cytochrome c is a poor acceptor. Also, the Crithidia methyltransferase appears to be stable to carry lysine methylation much further to completion than do the enzymes from yeast and Neurospora, which produce very low degrees of methylation in native cytochromes c.

Amino Acids↗
PubMed1980

Relationships of maternal weight gain, prepregnancy weight, and infant birthweight. Interaction of weight factors in pregnancy.

A study of the effects of restricted vs. unrestricted maternal caloric intakes upon infant birthweights was conducted in a large, middle-class, private obstetrical practice in Madison. Wis. Comparison of data relating to 602 pregnancies showed that increases in maternal weight gain accompanied significant and desirable increases in infant birthweight. Findings in this study support the statement of the Food and Nutrition Board that caloric restriction during pregnancy may be undesirable and probably is detrimental to the newborn.

Adult↗
PubMed1978

Double-blind trial of thiothixene and chlorpromazine in acute schizophrenia.

In a double-blind trial of chlorpromazine and thiothixene conducted with 79 acutely ill, newly hospitalized schizophrenic patients, chlorpromazine and thiothixene were shown to be equally effective in producing meaningful symptomatic improvment over an average period of approximately 3 weeks, as measured by Global Assessments (CGI), BPRS, and NOSIE.

Acute Disease↗
PubMedDate not supplied

Autonomic responses are elicited by electrical stimulation of the medial but not lateral frontal cortex in rabbits.

Conscious rabbits received electrical stimulation of the anterior midline frontal cortex or lateral somatosensory and motor cortex, through chronically-implanted electrodes. Active sites for cardiovascular responses were found in the anterior midline cortex, but stimulation of the frontolateral sensory-motor cortex either did not elicit cardiovascular changes or elicited only small and variable changes when stimulated. The heart-rate response elicited was, in all cases, bradycardia. All blood pressure changes consisted of depressor responses. Stimulation of the lateral frontal cortex almost always resulted in increases in EMG activity, although many placements were observed in the medial frontal cortex that were unaccompanied by movement. In all cases in which depressor responses and bradycardia were elicited, increases in respiration rate and decreases in depth also occurred. The active area from which bradycardia and depressor responses were elicited forms the medial portion of the cortical projection area of the mediodorsal nucleus of the thalamus and thus may be involved in the autonomic accompaniments of the behavioral activities, i.e. learning and memory processes, associated with this nucleus.

Animals↗
PubMedDate not supplied

Implementation of a computerized information system in a long-term care facility.

The successful implementation of computerized nursing information systems requires the completion of many tasks and the participation of many persons. In 1989, Pulliam and Boettcher described a six-step process for introducing computerized information systems into long-term care facilities. This article describes the process, particularly the implementation phase, as it actually happened in a 124-bed facility in a mid-Atlantic state. This facility found that successful implementation requires a systems coordinator who is a professional nurse who understands the needs of the patients, can integrate information with the computer system, and can provide on-going support for the users.

Delaware↗
PubMedDate not supplied

Project head start.

Explore the source record for details and available documents.

Child↗