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Biomedical subjects

G Davis

Publications and source records attributed to G Davis.

At least 199 records · Page 11Linked to original sources
PubMed1980

Later stages of development of the periotic duct and its adjacent area in the human fetus.

The later stages of development (16-40 weeks in utero) of the periotic duct and its adjacent areas in the human fetus indicate that the critical stages of development occur in four specific time related stages over a six-week period (20-26 weeks). First, the petrous apex ossifies to separate th inferior cochlear vein into the canal of Cotugno and forms the medial wall of the cochlear aqueduct (22 weeks); second, the canalicular otic capsule fuses with the cochlear otic capsule to obliterate Hyrtl fissure and forms of the lateral wall of the cochlear aqueduct (24 weeks); third, progressive bone deposition to the medial surface of the membranous labyrinth and cochlea at the petrous apex elongates the periotic duct and cochlear aqueduct (32 weeks in utero); and fourth, active arachnoid tissue ingrowth into the periotic duct occurs at 20-24 weeks and 34-40 weeks in utero. The terminal event is widening of the CNS opening of the periotic duct at 32 weeks in utero. The periotic duct and cochlear aqueduct length increase with gestation from 25 weeks until term. The periotic duct width remains the same throughout the gestation. The cochlear aqueduct width diminishes with gestational age. The periotic duct remains patent throughout 16-40 weeks in utero.

Cochlea↗
PubMed1979

Coliform status of domestic swimming pools.

An investigation of maintenance, usage, and coliform status of water in 104 domestic swimming pools in 13 Brisbane suburbs was made in January, 1978. The results showed that domestic pools are often imperfectly serviced, and are potential infection sources. The need for health education of pool owners, and for more reliable methods of pool sanitization is emphasized.

Escherichia coli↗
PubMed1979

Social work and dentistry in clinical, training and research collaboration.

The knowledge and knowledge building skills of social workers can improve in three ways the quality and type of services provided to dental patients. First, social workers can be involved in the training of dental professionals so as to improve their interactions with patients. Second, social workers may provide social work clinical services to dental patients. Finally, social workers can conduct research that can add to the body of knowledge on patient behaviors relevant to dental treatment. This paper outlines a program conducted by social workers that incorporates all three of these activities.

Dentistry↗
PubMed1978

Fetal respiratory distress causing CNS and inner ear hemorrhage.

Fifty-two consecutive temporal bones of infants who died neonatally, or in utero of natural causes, were studied. Complete autopsies were performed. Twenty-eight infants had a variety of pulmonary disorders which resulted in severe respiratory distress prior to their death. Of these, the majority had bleeding intracranially and into the inner ear. There were five major pathways of central nervous system and subarachnoid hemorrhage involvement of the inner ear: 1) the modiolus, 2) cochlear aqueduct, 3) retrograde via the cochlear vein, 4) episodes of spontaneous bleeding into various compartments of the inner ear, and 4) hemorrhage via the otic capsule. The remaining 24 infants died of other natural causes. Two had CNS bleeding with no extension to the inner ear. We propose that there is a syndrome which consists of 1) neonatal respiratory distress, 2) intracranial hemorrhage, and 3) bleeding into the inner ear--an extension of a subarachnoid or subependymal matrix bleeding diathesis.

Cerebral Hemorrhage↗
PubMed1978

99mTechnetium penicillamine scans: an index of differential renal function.

The relative renal accumulation of 99mtechnetium penicillamine was evaluated as an index of differential renal function. Regions of interest were assigned over each kidney with a computer and the renal uptake of 99mtechnetium penicillamine was determined. A simple background correction was made by subtracting the renal activity at 10 minutes from that at 25 minutes. The percentage of 99mtechnetium penicillamine accumulation in the left kidney was correlated with the percentage of the total effective renal plasma flow to the left kidney. Effective renal plasma flow was determined after the intravenous injection of 131 I hippuran using a highly sophisticated computerized technique that has been validated in patients by comparison with traditional split renal function studies. The correlation coefficient between the 2 measurements was 0.97. In addition to its use as an index of differential effective renal plasma flow 99mtechnetium penicillamine is an excellent cortical imaging agent and the relative distribution of 99mtechnetium penicillamine between the 2 kidneys and within a single kidney can be assessed qualitatively by visual inspection of the scan.

Adult↗
PubMed1977

Regional co-ordinator for haemophilia in domiciliary practice.

The North-east Thames Region has appointed a nursing sister to co-ordinate the organisation of care for haemophiliacs in the region. As a result of the appointment, facilities for home treatment have expanded rapidly. Several associate centres providing care to haemophiliacs have been set up around the region in addition to the four main haemophilia centres, which are all in the south-west corner of the region. As well as providing support and supervision of patients on home treatment, the co-ordinator helps to place haemophiliac children in suitable schools, maintains the regional register of haemophiliacs, and has a more general role in ensuring that services are available where they are needed throughout the region.

England↗
PubMed1977

New practical treadmill protocol for clinical use.

A new continuous treadmill protocol (USAFSAM) has been designed using a constant treadmill speed (3.3 miles/hour) and regular equal increments in treadmill grade (5%/3min). The constant treadmill speed requires only initial adaptation in patient stride, reduces technician adjustments and produces less electrocardiographic motion artifact than do protocols using multiple or higher treadmill speeds, or both. The regular equal increments in treadmill grade are easy to implement and provide a larger number of work loads than do protocols that are discontinuous or require larger changes in work load. The USAFSAM protocol was compared with the older Balke-Ware protocol in 26 healthy men (aged 30 to 59 years). Each fasting subject completed two maximal treadmill tests from each protocol. Measurements included minute heart rate from the electrocardiogram, auscultatory blood pressures and oxygen consumption obtained with standard techniques. Similarities in between-protocol measurements for submaximal and maximal treadmill efforts were impressive; differences were small and unimportant. Further, both protocols showed equal reproducibility for the measurements noted. Importantly, time to maximal effort was reduced by 24% with the USAFSAM protocol. The USAFSAM treadmill protocol has since been used in more than 500 clinical and screening examinations, thus confirming its advantages and practicality for routine clinical stress testing. Normal reference values previously established for the Balke-Ware protocol are shown to apply to the new USAFSAM protocol as well.

Adult↗
PubMed1977

99mtechnetium penicillamine: a renal cortical scanning agent.

99mTechnetium penicillamine, a renal cortical imaging agent, can be used to provide a rapid, safe and non-invasive assessment of renal morphology and the renal vascular supply. Since this agent is not excreted significantly during the imaging procedure cortical scans of high quality can be obtained without image deterioration owing to a superimposed collecting system. These scans, which are clearly superior in anatomical detail to earlier scans using 131I hippuran, can be obtained along with the 131I hippuran renogram when the patient comes to the nuclear medicine department. Herein we demonstrate the anatomical detail it is now possible to achieve by presenting the cortical renal scans and accompanying radiograms from 5 patients with different renal pathology.

Adenocarcinoma↗
PubMed1976

Parameters of liver spleen scans as an indication of portal hypertension.

In 37 patients with suspected portal hypertension, the bone marrow and splenic uptake on 99mTc-sulfur colloid liver spleen scans correlated with increased portal pressures. The degree of increase was not possible to predict from the scans. In portacaval shunt patients, those with normal portal pressures could not be separated from those with elevated pressures on the basis of the scan alone.

Bone Marrow↗
PubMed1975

Prediction of maximal oxygen consumption. Comparison of the Bruce and Balke treadmill protocols.

This study investigated the hypothesis that an individual's maximal oxygen consumption can be realistically predicted by the maximal time achieved in the Balke or Bruce treadmill protocols. The range of maximal oxygen consumption that can be expected for healthy individuals of any given age and activity was also evaluated. The maximal oxygen consumptions achieved by 79 men exercised using the Balke protocol and 77 men using the Bruce protocol were linearly regressed by a least-squares fit technique on maximal treadmill time and on age with activity status classified. Statistical analysis demonstrated an inadequate relationship for predicting maximal oxygen consumption from maximal treadmill time using either protocol. Also, maximal oxygen consumption correlated poorly with age even though activity status was considered. These findings make the nomogram for predicting an individual's functional aerobic impairment a clinical technique of questionable value. Since maximal oxygen consumption can only be grossly estimated from the maximal time performed in the Bruce or Balke protocols, there is no necessity to use them in preference to other clinically acceptable protocols.

Adult↗