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Biomedical subjects

R Johnson

Publications and source records attributed to R Johnson.

At least 703 records · Page 39Linked to original sources

Acute inhalation toxicity of neutralized chemical agent identification sets (CAIS) containing agent in chloroform.

An acute head-only inhalation study was conducted in rats exposed for 1 h to product solution (wastestream) resultant from the chemical neutralization of Chemical Agent Identification Sets (CAIS) containing agent (sulfur mustard (HD), nitrogen mustard (HN-1) or lewisite (L)) in chloroform. Groups of Sprague-Dawley rats were exposed to varying concentrations (24000, 18000, 12000 or 6000 ppm) of CAIS wastestream. An additional group was exposed to the vehicle (chloroform/t-butanol) only, at a concentration equivalent to the concentration of vehicle at the highest exposure level. Animals were evaluated for toxic effects, including assessment of toxicant-induced alterations to the ocular and respiratory systems. Mortality on exposure to 24000 ppm of test article or to vehicle alone was high. Mortality in the other exposure groups was roughly proportional to the concentration of test article (wastestream). Toxic signs were consistent with exposure to solvent system components (chloroform/t-butanol) and to agent decomposition products/by-products. Incidence and severity of ocular effects were similar in vehicle control and treatment groups. The salient respiratory effect observed was a decreased minute volume, which was also noted in vehicle and treatment groups.

Animals↗

Physical, psychological and social well-being of women with breast cancer: the influence of disease phase.

While research exists on the well-being of women during a specific phase of breast cancer, little research exists in which researchers utilized the same instruments to examine differences in women's well-being, based on the phase of their breast cancer. Using a trajectory framework, the purpose of this study is to examine the differences in the physical and social well-being of women during the following breast cancer states: newly diagnosed, adjuvant therapy, stable disease and recurrent disease. The convenience sample consisted of 35 women newly diagnosed with breast cancer, 52 women with breast cancer undergoing adjuvant therapy, 84 women whose breast cancer was considered stable and 64 women with recurrent breast cancer. Participants completed a packet of questionnaires which contained a demographic questionnaire, Short Form-36 (SF-36) Health Survey, a researcher designed (RD) questionnaire, Cancer Rehabilitation Evaluation System-Short Form (CARES-SF) and the Brief Symptom Inventory (BSI). Descriptive statistics, analysis of variance, and general linear F-tests were used to analyze the data. Differences were found across phases of disease on various subscales, including those representing perceived health states, overall impact, medical interactions, physical function, role function, fatigue, pain, social function and satisfaction with health. No significant differences were found between groups on the BSI subscales with the exception of somatization, global psychosocial measures, sexual and marital relation subscales. While individuals with recurrent disease often experienced more difficulties with their well-being than women in the other groups, women newly diagnosed and in the adjuvant group experienced more difficulties in select areas of well-being when compared with women in the stable group. Health care professionals need to recognize differences between groups to better meet the needs of patients with a breast cancer diagnosis.

Adaptation, Physiological↗

Adenine arabinoside 5'-monophosphate treatment of chronic type B hepatitis.

Six patients with chronic type B hepatitis were treated with adenine arabinoside 5'-monophosphate at a dosage of 10 to 15 mg per kg per day for 10 days. All demonstrated an immediate and marked decrease in serum hepatitis B virus DNA and DNA polymerase, and 5 of the 6 became negative for both markers by the end of the period of therapy. One patient remained negative for hepatitis B virus DNA and DNA polymerase when therapy was discontinued. This patient subsequently exhibited clinical, serum biochemical, and histological remission in disease activity concurrent with seroconversion from hepatitis B e antigen to antibody. In the remaining five patients, serum hepatitis B virus DNA and DNA polymerase returned to pretreatment values soon after therapy was stopped, and these patients demonstrated no significant changes in clinical, biochemical, serological, or histological features of the disease. Side effects of the therapy were mild and transient. These results suggest that a 10-day course of adenine arabinoside 5'-monophosphate is not adequate to induce permanent amelioration of infection and disease activity in the majority of patients with chronic type B hepatitis.

Adult↗

The natural history of medical and psychiatric disorders in an American Indian community.

In 1969, a Pacific Northwest American Indian community cohort (n = 100) was interviewed for the presence of physical and psychiatric illnesses. The same community was studied again in 1988. This study describes the outcome among the original 100 subjects. The schedule for Affective Disorders and Schizophrenia Lifetime Version (SADS-L) served as the basic interview instrument, supplemented by data from medical records, death certificates, and medical and community informants. Twenty-five subjects had died, 13 from cardiovascular disorders and seven from alcohol-related illnesses. Among the 46 subjects re-interviewed, hypertension, heart disease, and diabetes had become significant sources of medical morbidity. Alcoholism was the most significant cause of psychiatric morbidity, particularly among males. This study indicates that greater attention should be focused upon prevention and treatment of alcoholism, cardiovascular disorders, and diabetes in this community and in other American Indian populations.

Adult↗

Air medical transport for the trauma patient requiring cardiopulmonary resuscitation: a 10-year experience.

INTRODUCTION: Air medical response and transport for the injured patient in cardiopulmonary arrest remain controversial. This study is a large, single-program experience. METHODS: A retrospective chart review and descriptive study of all injured patients requiring cardiopulmonary resuscitation (CPR) immediately before or during air medical transport. The crew functioned under advanced cardiac life support/advanced trauma life support protocols. SETTING: The patients, when transported, went to a variety of facilities, with the majority of patients transported to a level-I trauma center. The service area was primarily rural. RESULTS: During 1985 to 1994, inclusive, there were 12,518 completed missions. A total of 320 injured patients required CPR (284 with blunt injury and 36 with penetrating injury), six of the 320 patients (1.9%) survived. Survivors and nonsurvivors did not differ significantly in age, mechanism of injury, time from initiation of CPR to arrival in the emergency department (ED), year of injury or initial cardiac rhythm. All survivors did, however, present to the ED in normal sinus rhythm with a palpable blood pressure. CONCLUSION: Air medical transport for the injured patient without signs of life following prehospital intervention appears futile.

Air Ambulances↗