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W S Smith

Publications and source records attributed to W S Smith.

18 recordsLinked to original sources
PubMed1992

The injuries to JFK.

Explore the source record for details and available documents.

Craniocerebral Trauma↗
PubMed1989

Proton NMR study of the influence on iron oxidation/ligation/spin state on the heme orientational preference in myoglobin.

Proton nuclear magnetic resonance spectroscopy has been utilized to demonstrate that the degree of heme orientational disorder within a given myoglobin protein matrix can be a sensitive function of the oxidation/ligation/spin state of the heme iron. For sperm whale deuterohemin-reconstituted myoglobin, the equilibrium was found to strongly favor (5.7 to 7.8 kJ/mol) the X-ray characterized heme orientation in all six-coordinate states, but with a considerable reduction in preference (to 1.6 kJ/mol) in the five-coordinate deoxy state. In native yellow fin tuna myoglobin, changes in heme orientational preferences of approximately 3 kJ/mol occur even between two six-coordinate ferric states differing solely in spin states.

Animals↗
PubMed1989

Effects of synchrony between primate corticomotoneuronal cells on post-spike facilitation of muscles and motor units.

Cross-correlating the activity of neighboring motor cortex neurons recorded with independent electrodes in behaving monkeys has revealed synchronization peaks, largely due to common synaptic input. Corticomotoneuronal (CM) cells produced post-spike facilitation (PSF) of rectified forearm electromyograms (EMG); 15 cells synchronized with CM cells showed no PSF. Five pairs of CM cells with overlapping muscle fields exhibited similar synchrony peaks. The contribution of this synchrony to facilitation of common target muscles was assessed by two new methods: selective spike-triggered averaging and convolution. They showed that the PSF is composed predominantly of effects mediated by output of the triggering cell, but may include a broad, shallow component mediated by synchrony with other CM cells.

Action Potentials↗
PubMed1988

Solvent isotope effects on NMR spectral parameters in high-spin ferric hemoproteins: an indirect probe for distal hydrogen bonding.

The influence of solvent isotope composition on 1H-NMR resonance position and linewidth of heme methyls has been investigated for a variety of high-spin ferric hemoproteins for the purpose of detecting hydrogen-bonding interactions in the heme cavity. Consistently larger hyperfine shifts and paramagnetic linewidths in 2H2O than 1H2O are observed for metmyoglobins and methemoglobin possessing a coordinated water molecule. The analysis of the dynamics of labile proton exchange in sperm whale metmyoglobin, and the absence of any isotope effects in the five-coordinate Aplysia metmyoglobin, indicate that the significant axial modulation of heme electronic structure by solvent isotope is consistent with arising from distal hydrogen-bonding interactions. The presence or absence of similarly large isotope effects on shifts and linewidths in other hemoproteins, depending on the presence of a bound water in the distal heme pocket, suggests that this isotope effect can serve as a probe for the presence of such bound water. The absence of any detectable isotope effect on either shifts or linewidths in resting-state horseradish peroxidase supports a five-coordinate structure with bound water absent from the vicinity of the iron.

Animals↗
PubMed1978

[Clinical studies of the antiarrhythmic efficacy of disopyramide phosphate (Norpace) (author's transl)].

The antiarrhythmic action of Norpace was investigated in three clinical studies. 1. A single blind placebo controlled study in 10 centers confirmed the antiarrhythmic action of Norpace in 120 patients with ventricular or supraventricular cardiac arrhythmias. It was shown by means of continuous ECG recordings that Norpace produced a statistically significant reduction in the frequency of both ventricular and supraventricular extrasystoles. Paroxysmal ventricular tachycardia was prevented in 70% of the patients. 2. In a double blind comparative study of Norpace and quinidine sulphate a similar antiarrhythmic action against ventricular and supraventricular extrasystoles was shown in both patient groups. In contrast, the tolerance of Norpace was markedly superior to quinidne sulphate. 3. An acute study of the action of Norpace was also conducted. Therapeutic plasma levels were attained within 2 1/2 hours following an initial single dose and within 60 to 120 minutes when this dose was doubled. Orally administered disopyramide phosphate has therefore proved effective in both the short and longer term treatment of various types of supraventricular and ventricular arrhythmias. Its antiarrhythmic properties are very similar to those of quinidine sulphate. The dosage of disopyramide phosphate should be sufficiently high and must be individualized. The dosage generally lies between 400 and 800 mg daily and should be given in 4 divided doses at intervals of 6 hours. To achieve rapid therapeutic effects an initial dose of 2 x 150 mg is recommended. This method of administration will produce effective therapeutic plasma levels within 1 to 2 hours. Due to possible negative inotropic effects it is necessary to digitalize patients with congestive heart failure and caution should be exercised in poorly compensated patients. Observed side effects were mainly of the anticholinergic type.

Administration, Oral↗
PubMed1976

A system for rapid analysis of long-term recordings of heart rate and other physiological parameters.

Using miniature cassette tape recorders, measurement of ECG and other physiological measures is possible in industrial or working situations. The development of a semi-automatic high speed processing system for analysis of the tape recorded data is described. This system decodes the signals on the tape, converts ECG to heart rate and presents a listing of the heart rate variation over the recording period, which may be up to 24 hours. A punched paper tape copy of the listing is used for input into a mainframe computer for subsequent analysis. The recorders and processing system have been used extensively for three years on a study of industrial work stress, and have proved reliable, accurate, and of sufficient sensitivity for in-depth analysis. They allow considerable data to be collected, permitting the thorough statistical analysis necessary for the interpretation of complex physiological responses.

Computers↗
PubMed1975

First-degree atrioventricular block: a cause of false malfunction of a mitral disc-valve prosthesis. Case report.

Malfunction of a prosthetic mitral disc valve was clinically suspected on the basis of absent valve closing sound and an early opening click in a patient with first-degree atrioventricular (A-V) block. Premature closure and opening of the prosthetic valve was demonstrated by echocardiography. All abnormal auscultatory, phonocardiographic, and echocardiographic findings disappeared promptly upon spontaneous restoration of normal A-V conduction. The possible hemodynamic mechanism is discussed, and attention is drawn to this conduction abnormality as a cause of erroneous diagnosis of prosthetic mitral valve malfunction.

Adult↗
PubMed1975

Segmental resection for chondrosarcoma.

Specific anatomical and pathological criteria for resectability of so-called central chondrosarcoma of the extremities were set forth and a method of treatment based on autoclaving the segment and surrounding it with massive amounts of fresh autogenous cancellous bone was used in eight patients. Follow-up ranged from 3.2 to 13.5 years. The advantages of the method are: ease of procurement of bone graft, absence of storage and measurement problems, and lack of need for rigid immobilization. No secondary procedures were required because of fracture, resorption, or infection.

Adult↗
PubMedDate not supplied

MR and CT findings in pulmonary artery sarcoma.

Pulmonary artery sarcomas are a rare and frequently forgotten cause of pulmonary artery occlusion. We present a case report that details magnetic resonance and new CT findings, which may help establish early diagnosis of this infrequently encountered tumor.

Aged↗