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Biomedical subjects

R H Jones

Publications and source records attributed to R H Jones.

At least 361 records · Page 20Linked to original sources
PubMed1976

The effect of positive end-expiratory pressure on regional ventilation and perfusion in the normal and injured primate lung.

Although positive end-expiratory pressure (PEEP) is being employed in the management of respiratory insufficiency, many of its physiological effects remain undetermined. The cardiopulmonary effects of PEEP as well as its effect on regional ventilation and perfusion were studied in 10 baboons before and after pulmonary injury with oleic acid. In the normal lung, there was significant improvement in oxygenation at a PEEP of 5 cm. of water secondary to improved ventilation and perfusion in all PEEP greater than 5 cm. of water produced increasing mismatch of ventilation and perfusion in all zones. After oleic acid was injected, hypoxemia was evident with a reversal of the normal ventilation-perfusion (V/Q) relationship between upper and lower lung zones. This mismatch of ventilation and perfusion was corrected at a PEEP of 15 cm. of water. It was reasonable to conclude that the use of PEEP in the injured lung exerts it beneficial effect by balancing regional ventilation and perfusion in addition to increasing functional residual capacity.

Animals↗
PubMed1976

Immunization against leptospirosis: vaccine trials with heat-killed whole cell and outer envelope antigens in hamsters.

Heat-killed whole cell and outer envelope antigens prepared from homologous virulent and avirulent strains of Leptospira serotypes canicola and pomona were evaluated for protecting hamsters against experimental leptospirosis. The heat-killed bacterins proved at least as effective as the outer envelope antigens, or more so, in providing protection against death and infection, and they are easier and more economical to prepare.

Animals↗
PubMed1975

Lymphocyte transformation in syphilis: an in vitro correlate of immune suppression in vivo?

Suppression of cellular immunity during primary and secondary infection may explain, in part, the unusual clinical evolution of syphilis. We have previously shown that lymphocytes from normal subjects undergo blastic transformation when exposed in vitro to Treponema refringens. This response was suppressed in patients with syphilis. the suppression being unrelated to serum factors. In the present paper we studied lymphocyte response in vitro to T. refringens, T. reiter, and T. pallidum as well as to monilia and trychophytins. The response to these antigens was suppressed in patients with syphilis although the response to phytohemagglutinin. pokeweed mitogen, and streptolysin was normal. These data support the hypothesis that human infection with T. pallidum is followed by a complex interaction between cellular and humoral immunity, the former being suppressed in primary and secondary stages.

Antigens, Bacterial↗
PubMed1975

Physiologic emboli changes observed during total hip replacement arthroplasty. A clinical prospective study.

Fat embolism does occur with introduction of femoral components during total hip replacement arthroplasty. If massive, abrupt severe irreversible interruption of pulmonary oxygen exchange or profusion can occur. Adequate intramedullary femoral canal venting can significantly reduce the amount or dosage of fat embolism and thereby reduce and prevent primary or superimposing secondary injury of the capillary-alveolar gas exchange area within the lungs. The occurrence of fat embolism supports the mechanical theory. It also demonstrates that a patient surviving the effects of the acute mechanical pulmonary insult may still have to survive the more common and typical clinical picture of the metabolic pulmonary disease result of fat embolism that likewise can be irreversible. To prevent the occurrence of fat embolism during femoral component insertion with total hip replacement arthroplasty, the following techniques are imperative: (1) adequate femoral intramedullary canal venting; (2) maintenance of pulmonary arterial oxygen tension; (3) maintenance of blood volume.

Aged↗