Biomedical subjects

J Burgess

Publications and source records attributed to J Burgess.

At least 91 records · Page 5Linked to original sources

PubMed1980

Morphology and ultrastructure of helical and nonhelical strains of Spiroplasma citri.

Cells of the nonhelical strain of Spiroplasma citri underwent changes of morphology comparable to those which occurred in the normal helical strain. Cells of the nonhelical strain had the same ultrastructural features as helical cells and released long flexible fibrils similar to those seen in other spiroplasmas. Nonhelical organisms showed an increased tendency to aggregate, forming cell clusters of an unusual annular form. The cytoplasmic membrane of the nonhelical strain lacked a single protein present in all helical strains. Loss of helicity associated with the senescence of spiroplasma cells was not accompanied by the disappearance of this protein. Differences in colony morphology were shown to be a consequence of motility, and a technique was developed which facilitated the identification of nonmotile organisms.

Bacterial Proteins↗

PubMed1979

New mechanical aid to physiotherapy in cystic fibrosis.

The force of impact and frequency of percussion by physiotherapists and parents of children with cystic fibrosis were analysed on a special test rig and incorporated in a prototype percussor. In adult volunteers and cadavers a maximum intrathoracic pressure could be achieved by a critical frequency of mechanical percussion which was higher than that reached by physiotherapists and parents. Consequently the percussor was redesigned to operate at this optimum frequency. It was then discovered that if the percussor was pressed firmly enough against the chest, this maximum intrathoracic pressure could be indicated by quivering of the voice. In a continuing study of intrathoracic pressures obtained mechanically and manually the Salford percussor's produced higher pressures than the physiotherapists' and maintained them constantly, while the physiotherapists' efforts and results varied from one to another. Hospital and domiciliary use of the percussor have shown it to help in the first stage of the physiotherapy routine for patients with cystic fibrosis. The percussor should enable adolescents and adults to treat themselves and encourage twice-daily and more effective chest treatments. It is easy to apply and its speed and efficiency should enable parents to improve the quality of their chest therapy for younger children at home. Its long-term benefits are difficult to assess because of the nature of the disease.

Adolescent↗

PubMed1978

Thymoma: a ten year review.

The histopathology, clinical features, treatment, and results are reported in twenty-nine patients with thymoma. Benign and malignant thymomas are differentiated by their invasive characteristics. Surgical excision is recommended for benign lesions. Surgical excision and postoperative irradiation are recommended for malignant thymomas irrespective of the predominant cell type. The recommended treatment for thymoma and the symptomatic results in myasthenia gravis are unpredictable.

Adult↗

PubMed1976

Echocardiographic assessment of the level of cardiac compensation in valvular heart disease.

The level of cardiac compensation in valvular disease was studied by relating echocardiographic and cardiac catheterization measurements. Three groups -- compensated, intermediately compensated, and decompensated -- were defined according to the left ventricular angiographic pattern and cardiac output. The echocardiographic ejection indices, percent left ventricular minor diameter shortening, ejection fraction, and fiber shortening rate were significantly higher than normal in compensated mitral regurgitation, lower then normal in compensated aortic stenosis, and within normal limits in compensated aortic insufficiency. In the decomposed state these indices were depressed. Intermediate compensation was best recognized by combining several echocardiographic variables into an echocardiographic score based on multivariate discriminant function analysis. Thus, the compensated volume overload states (aortic and mitral regurgitation) and pressure overload state (aortic stenosis) have separate sets of "normal" echocardiographic values; low ejection indices characterize the decompensated group, while recognition of intermediate compensation requires analysis of multiple echocardiographic variables.

Adult↗

PubMed1975