Search PubMed⌕ Search

Biomedical subjects

A Smith

Publications and source records attributed to A Smith.

At least 955 records · Page 53Linked to original sources
PubMed1989

Factors affecting the stability of nutritional emulsion mixtures.

The stability of oil droplets in complex nutritional admixtures is known to be affected by the presence of amino acids, dextrose and electrolytes. Hospital Pharmacists unable to meet demands for TPN admixtures sometimes turn to specialised commercial units but the supply of lipid admixtures by any facility remote from the user raises further challenges to admixture stability from various sources through exposure to temperature variations, transit effects etc. A number of interesting variances have been found in lipid admixtures arising from factors not previously recognised as significant. The batch of emulsion, container type and conditions of storage prior to use have been demonstrated to affect a moderately stable admixture. Whilst requiring further investigation, such factors must be considered for all new regimens and particularly to ensure the robustness of mixtures provided through a Compounding Service for Hospital or Home patients.

Journal Article↗
PubMed1989

The prevention of plasticizer migration into nutritional emulsion mixtures by use of a novel container.

The presence of di-(2-ethylhexyl)phthalate in poly (vinyl chloride) has led to concern regarding the potential for plasticizer migration from this widely used material into fluids for infusion, particularly nutritional admixtures containing lipid. A novel container is reported which combines the advantages and versatility of poly(vinyl chloride) without the disadvantage of plasticizer migration into the infused fluid.

Journal Article↗
PubMed1989

Cervical screening: what are the communication problems?

Computer-managed call and recall schemes offer the opportunity for effective cervical screening. However, such schemes involve several different agencies, often independent of one another. As a result, problems of communication can arise. This paper discusses potential areas of difficulty and presents some suggestions for improvement.

Adult↗
PubMed1989

Immunolocalisation and imaging of small cell cancer xenografts by the IgG2a monoclonal antibody SWA11.

We describe here a murine monoclonal antibody of the IgG2a isotype which was generated against the SW2 human small cell carcinoma cell line. The antibody, SWA11, was shown to bind to a partially defined antigen preferentially expressed on cell lines of small cell carcinoma origin. In vitro binding studies revealed 6.1 x 10(5) antigenic sites on the SW2 cell line and the Ka to be 1.2 x 10(9)M-1. Following injection into mice bearing 1-2 cm3 SW2 xenografts, SWA11 showed strong selective accumulation in the small cell heterotransplants with a tumour to blood ratio of 7.5:1 at day 4. Other tumour to organ ratios were similarly high at 19:1, 22:1 and 12:1 for liver, kidney and spleen respectively. The absolute amount of SWA11 which localised was 10.5% of total injected material per gram tumour at day 2 and this level did not markedly decrease by day 4. The high ability of SWA11 to localise to SCC xenografts was confirmed by external gamma scintigraphy. The potential application of SWA11 as a model system for in vivo radioimmunotherapy is discussed.

Animals↗
PubMed1989

Neural drive to muscles in stuttering.

EMG recordings were made from muscles of the jaw, lip, and neck during speech of 10 stutterers and 10 nonstutterers. One-second records of disfluent behaviors of stutterers and of fluent speech of the normal speakers were analyzed by computing cross correlations between all possible muscle pairs and spectra for each muscle channel. The cross correlation analysis indicated that for both the disfluent behavior of stutterers and the fluent speech of nonstutterers, jaw muscles (including antagonistic pairs), lip muscles, and neck muscles tend to be coactivated. Thus, no dramatic differences in muscle activation patterns were revealed in the correlational analysis. In contrast, spectral analysis revealed differences between muscle activity during disfluent behavior and fluent speech. During disfluencies the muscles of 6 of the stutterers showed large, rhythmic oscillations in the frequency range of 5 to 12 Hz. Large oscillations were not observed in this frequency range in the muscle activity of normal speakers. The oscillations in muscle activity during disfluencies generally occurred at the same frequency in the various muscle systems studied. These results suggest that diverse muscles are subject to common oscillatory synaptic drive during disfluent behaviors and that this drive is disruptive to speech production. A reasonable speculation is that the disruptive oscillatory drive is produced by tremorogenic mechanisms.

Adult↗
PubMed1989

Surface recordings of respiratory muscle activity during speech: some preliminary findings.

Bipolar electromyographic (EMG) recordings were made from six chest wall and nasal sites with disk electrodes attached to the skin. Electrode locations were based on previous studies of nonspeech breathing and were designed to sample the activity of both primary and accessory respiratory muscles. EMG activity was sampled while subjects performed a series of speech and nonspeech tasks. The results revealed that surface electrodes could sample the activity of respiratory muscles during speech and other ventilatory tasks, particularly during the expiratory phases of the breathing cycle.

Adolescent↗
PubMed1989

A review of the effects of colds and influenza on human performance.

Results from our research on the effects of colds and influenza on performance have led to the following conclusions. First, these illnesses have significant effects on performance efficiency, although the nature of the impairment depends on the type of virus and the task being performed. For instance, influenza slows reactions to stimuli appearing at irregular intervals, or in unknown locations, whereas colds impair hand-eye co-ordination. Performance impairments have also been found with sub-clinical infections, during the incubation period of the illness, and after the symptoms have gone. These results have important implications for occupational safety and efficiency.

Efficiency↗
PubMed1989

Computer-managed call and recall for cervical screening: a typology of reasons for non-attendance.

Three pilot studies looked at women who had not attended for cervical screening following a computer-generated invitation to a health authority clinic. From these a typology of reasons for non-attendance for computer-managed screening has been developed, specifying inaccessibility, ineligibility, unsuitability, failure of communications, misclassification and refusal because of practical problems, inappropriate beliefs or attitudinal barriers. Underlying the typology are issues connected with the inaccuracy of the database, service organization and provision, and the characteristics of the women themselves.

Appointments and Schedules↗
PubMed1989

Control-related cognitions and depression among inpatient children and adolescents.

In previous studies, children with numerous depressive symptoms have shown two patterns of control-related cognition: (1) low levels of perceived personal competence, and (2) "contingency uncertainty"--confusion regarding the causes of significant events. The generality of these findings was tested for more seriously disturbed children. Three child inpatient samples, from separate psychiatric hospitals, completed the Children's Depression Inventory (CDI) plus measures of control-related beliefs. In all three samples, the findings resembled those of previous studies: CDI scores were significantly related to low perceived competence and to contingency uncertainty; by contrast, CDI scores were only weakly related to perceived noncontingency. The findings suggest that depressive symptoms in children may be (1) more closely linked to "personal helplessness" than to "universal helplessness," and (2) more closely linked to uncertainty about the causes of events than to firm beliefs in noncontingency. The findings carry implications for etiology and treatment of child depression.

Adolescent↗
PubMed1989

Post mortem findings in a patient with 46,XX,fra(2)(q13).

A severely mentally retarded girl who suffered from grand mal seizures, myoclonic jerking and ataxia died at 18 years of age. Chromosome studies, before and after death revealed a fragile site on chromosome 2q13, the expression of which was greater in peripheral blood than in fibroblasts on two occasions. Post mortem findings did not reveal any abnormality which could be attributed to this fragile site.

Acute Disease↗
PubMed1989

Evaluation of a children's hospital medical peer review programme.

The records of medical peer review meetings at the Royal Children's Hospital, Melbourne, were audited for the period 1983-87. This investigation focused on the peer review process, but also evaluated the extent to which recommended changes in medical practice were carried out. The results showed that few recommendations arose from the meetings despite the clear recognition of a number of problem areas. In the instances where firm recommendations were made, few appeared to have been implemented. The main reasons for this failure were: (i) the review was not an integrated part of the medical management structure of the hospital; (ii) recommendations were frequently not made despite clear expressions of the need for action; (iii) the absence of a designated individual to ensure that recommended actions were implemented, together with the lack of a feedback or internal review process to monitor effectiveness; and (iv) a relatively low profile of the peer review. Despite these shortcomings, the peer review is widely perceived to be a valuable exercise, especially as a general educational tool. However, its potential is far greater, and a model is proposed for a more effective medical peer review programme.

Australia↗
PubMed1989

A review of the effects of noise on human performance.

The present review is concerned with the effects of noise, especially moderate intensity noise on performance. The review covers recent empirical results and theoretical approaches, and examines the importance of the nature of the noise, individual differences in response to noise, and other factors which modify the effects of noise. A central theme of the review is that it is essential to consider the nature of the task being performed in noise, and a profile of strategies of performance in noise is presented. Finally, recommendations are made about the direction and methodology of future research.

Attention↗
PubMed1989

The reproducibility of gnathosonic recordings over time.

Gnathosonic recordings are obtained on rapid closure of the teeth to occlusion. A general relationship between gnathosonic tracings and occlusal contact patterns has been demonstrated. Variation of gnathosonic recordings over time for the same individual has not been satisfactorily investigated. The present study suggests that recordings taken at the same sitting are relatively reproducible but reproducibility over time is not high. The series of recordings obtained in this study suggests caution when interpreting a single series of gnathosonic tracings.

Adult↗
PubMed1989

Post-orthodontic occlusal function.

The significance of orthodontic treatment in the aetiology of temporomandibular dysfunction continues to be a matter of controversy. However, the evidence of any association has been generally negative. This investigation involved the examination of a study group of 87 post-orthodontic patients, the average time out of all retention being 52 months. They were compared with an untreated control group. Signs and symptoms of temporomandibular disfunction were assessed for both groups. In only one instance, soft joint click, was there found to be a significant association between the treatment category and the occurrence of the symptom, there being a higher rate of soft clicks in the post-treatment group. While this may be ascribed to orthodontic treatment, there was also a different restorative pattern in the two groups. No other significant associations were found.

Adult↗