PubMed Health⌕ Search

Biomedical subjects

R Hedges

Publications and source records attributed to R Hedges.

11 recordsLinked to original sources

Acute radiation toxicity assessment of a 3-D conformal head and neck radiation treatment technique.

Patients undergoing radiation treatment for head and neck cancer have many critical structures within or adjacent to the treatment area. Avoiding these critical structures is more efficient and easier using 3-D conformal planning. At Sir Charles Gairdner Hospital an investigation into the acute radiation toxicity was undertaken when the head and neck treatment technique was changed from the conventional 2-D plan to the conformal 3-D plan. Although the primary target volume (PTV), fraction size and overall dose remain the same for the two techniques, differing beam configurations mean that treatment fields enter and exit through different parts of the head and neck. Ten patients were initially assessed to gain a baseline appearance of their head and neck region, and then graded weekly according to the toxicity criteria during treatment and at 4, 8 and 12 weeks after treatment. The results of the assessment indicate that there is no increase in toxicity as a result of treating using the conformal head and neck technique.

Acute Disease↗

Staple food intake in a rural village in Verata, Fiji.

An assessment of food intake and body composition in twenty women in a relatively isolated rural village in Fiji was made. Subcutaneous fat distribution was assessed by the measurement of subscapular and triceps skin folds. Compared with measurements made on Polynesian and European women in New Zealand it was found that the Fiji women had relatively more central subcutaneous fat than Polynesian or European. Diet was assessed by two 7 day periods of diet diaries and analysed by food type. The two main foods eaten were cassava and flour based goods.

Adipose Tissue↗

Vascular surgical society of great britain and ireland: deaths from ruptured abdominal aortic aneurysm in wales

BACKGROUND: The aim was to determine the true incidence and operative mortality rate of patients with ruptured abdominal aortic aneurysm (AAA) who reach hospital alive in Wales. METHODS: Patients presenting with a ruptured AAA between September 1996 and August 1997 were analysed. The data were collected prospectively by an independent body, observing strict confidentiality. RESULTS: Two hundred and thirty-three patients with confirmed ruptured AAA were identified. One hundred and thirty-three patients (57 per cent) underwent attempted operative repair. Eighty-five (64 per cent) died within 30 days. All 100 patients who received no operation died. Of the 233 patients, 92 were admitted under vascular surgeons (VSs) and 141 under non-vascular surgeons (NVSs). VSs operated on 82 patients (89 per cent) of whom 50 (61 per cent) died; NVSs operated on 51 (36 per cent) of whom 35 (69 per cent) died. CONCLUSION: This study is the only independent prospective study of death among patients with ruptured AAA who reached hospital alive. Some 57 per cent of the patients with a ruptured AAA were operated on. The operative mortality rate was 64 per cent and the overall mortality rate was 79 per cent. VSs were significantly more aggressive (89 per cent) in the management of ruptured AAA (i.e. more likely to operate) than NVSs (36 per cent) (P < 0.0001). Despite this, the operative mortality rate for VSs was 61 per cent, whereas for NVSs it was 69 per cent (P = 0.372). The overall mortality rate (including operated and non-operated patients) for NVSs (89 per cent) was significantly higher than that for VSs (65 per cent) (P < 0.0001). In Conclusion:, ruptured AAA is common in Wales and associated with a high mortality rate even when managed by VSs.

Journal Article↗

Paleolithic and neolithic lineages in the European mitochondrial gene pool.

Phylogenetic and diversity analysis of the mtDNA control region sequence variation of 821 individuals from Europe and the Middle East distinguishes five major lineage groups with different internal diversities and divergence times. Consideration of the diversities and geographic distribution of these groups within Europe and the Middle East leads to the conclusion that ancestors of the great majority of modern, extant lineages entered Europe during the Upper Paleolithic. A further set of lineages arrived from the Middle East much later, and their age and geographic distribution within Europe correlates well with archaeological evidence for two culturally and geographically distinct Neolithic colonization events that are associated with the spread of agriculture. It follows from this interpretation that the major extant lineages throughout Europe predate the Neolithic expansion and that the spread of agriculture was a substantially indigenous development accompanied by only a relatively minor component of contemporary Middle Eastern agriculturalists. There is no evidence of any surviving Neanderthal lineages among modern Europeans.

Agriculture↗

Molecular genetic analyses of the Tyrolean Ice Man.

An approximately 5000-year-old mummified human body was recently found in the Tyrolean Alps. The DNA from tissue samples of this Late Neolithic individual, the so-called "Ice Man," has been extracted and analyzed. The number of DNA molecules surviving in the tissue was on the order of 10 genome equivalents per gram of tissue, which meant the only multi-copy sequences could be analyzed. The degradation of the DNA made the enzymatic amplification of mitochondrial DNA fragments of more than 100 to 200 base pairs difficult. One DNA sequence of a hypervariable segment of the mitochondrial control region was determined independently in two different laboratories from internal samples of the body. This sequence showed that the mitochondrial type of the Ice Man fits into the genetic variation of contemporary Europeans and that it was most closely related to mitochondrial types determined from central and northern European populations.

Animals↗

The analysis of interpersonal perceptions as a repertory grid.

In order to set goals and evaluate progress in therapy with couples it is important to begin with a clear formulation of the problem. The technique described provides quantitative data on three aspects of a relationship. Firstly, the extent to which a couple are in fact using a common language. Second, the extent to which they agree, understand each other's point of view, and realize how they are understood. Thirdly, the differences between their perception of the present and their goals for themselves and one another in the future. The investigation uses personal constructs elicited from the couple and the results are analysed as a repertory grid. Summary measures provided by the grid analysis organize the large amount of data and provide a general context for understanding the relationship within which particular aspects can be identified for more detailed analysis.

Adult↗