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K C Simmons

Publications and source records attributed to K C Simmons.

11 recordsLinked to original sources
PubMed1994

Cyanomet human hemoglobin crystallized under physiological conditions exhibits the Y quaternary structure.

Cyanomet human hemoglobin has been crystallized at a chloride ion concentration and pH similar to physiological conditions. Molecular replacement calculations definitively show that the hemoglobin subunits are arranged in the Y quaternary form recently discovered in carbon monoxy hemoglobin Yp-silanti (beta 99 Asp-Tyr), and subsequently observed in carbon monoxy normal human hemoglobin crystallized at low ionic strength and low pH. The structure has been refined at 2.09 A resolution to an R-value of 0.232, and further refinement is currently underway. Although the refinement is not yet complete, our results are the first indication that the Y structure may represent an important quaternary form of liganded hemoglobin under physiological buffer conditions. These results suggest the need for a reexamination of structure-function correlations in the hemoglobin system.

Buffers↗
PubMed1985

Predictive value of quantitative renography for successful treatment of atherosclerotic renovascular hypertension.

Twenty patients with severe atherosclerotic renal artery stenosis were studied by quantitative gamma camera renography before angioplasty or surgery. Sixteen patients were treated by angioplasty and two each by bypass surgery and nephrectomy. Total and relative renal function, renal perfusion, and tracer transit times through the affected and contralateral kidney were calculated. All but one of the angioplasty patients and one of the two bypass surgery patients also had quantitative renography performed one to two weeks after treatment to assess changes in renal function. In the remaining four patients, changes in renal function were assessed by serial serum creatinine estimations. Patients were classified as cured, improved, or not improved according to their blood pressure response. Five had evidence of unilateral functionally significant stenoses and normal contralateral kidneys (four cured, one improved). Ten had functionally significant stenoses but with abnormal contralateral kidneys (all improved). Five had no evidence of functionally significant stenoses (all not improved). Quantitative renography provides functional and prognostic information to complement anatomical assessment by angiography. It is a simple, safe, and non-invasive means of predicting the outcome for patients with hypertension and renal artery stenosis.

Adult↗
PubMed1980

CT of intracerebral haemorrhage due to mycotic aneurysms--case report.

The CT findings in a case of intracerebral haematoma due to rupture of a mycotic aneurysm are presented. In addition to the haematoma, CT demonstrated small focal areas of cortical enhancement, which corresponded to the peripheral aneurysms seen on angiography. Such findings are thought to be characteristic; a brief differential diagnosis is discussed.

Adult↗
PubMedDate not supplied

The use of the Mayo Clinic system for differential diagnosis of dysarthria.

The purpose of this study was to determine clinicians' attitudes toward the Darley, Aronson, and Brown (1969a, 1969b; 1975a) method of classification for differential diagnostic of dysarthria. A national telephone survey was conducted of 100 speech-language pathologists involved in the assessment and treatment of patients with dysarthria. Clinicians were questioned about their use of differential diagnosis as part of their service delivery to persons with dysarthria. Questions also focused on clinicians' perceptions of the helpfulness and difficulties of differential diagnosis. Results indicated that most clinicians use the Darley et al. (1969a, 1969b; 1975a) classification system for the differential diagnosis of dysarthria, stating that it is helpful in the design of a treatment protocol. A trend toward decreased perceived difficulty of differential diagnosis with increased years of work experience was observed. The clinical and academic training implications of these findings are discussed.

Data Collection↗