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Biomedical subjects

J H Nelson

Publications and source records attributed to J H Nelson.

At least 91 records · Page 5Linked to original sources
PubMed1976

Pretreatment staging.

Renewed emphasis on pretreatment staging of gynecologic malignancies has resulted from a number of reports on surgical staging of malignant cervical, endometrial, and ovarian lesions. These reports have shown that by pretreatment staging, in significant numbers of patients, more advanced disease was detectable than by the usual clinical methods. From 32% to 46% of patients with stage III cervical carcicarcicarcinoma have been found to have metastatic disease in the para-aortic nodes. Diaphragmatic and para-aortic node metastases have been reported in patients with ovarian carcinoma recently in significantly higher incidences than as previously detected. The pelvic lymph nodes have been shown to be involved in 11% to 13.5% of patients with stage I endometrial carcinoma. Twelve and one-half percent had metastases to the para-aortic nodes. These data suggest the need for more accurate definition of extent of disease prior to treatment. Improvement in survival rates will not necessarily follow, but modifications in treatment must be tried.

Aorta↗
PubMed1976

Diatom diversity as a function of insecticidal treatment with a controlled-release formulation of chlorpyrifos.

Following treatment with a controlled-release formulation of chlorpyrifos, no substantial differences between diversity estimates were evident for 6 post-treatment weeks for both treated and control plots. By post-treatment week 12, significant decreases in diversity estimates occurred in treated plots, suggesting that a directly proportional relationship exists between chlorpyrifos concentrations and reduced diatom colonization through time. Comparatively, diatom colonization progress "normally" and populations proceeded toward "maturity" in the control plots as indicated by the increase in the diversity estimates between post-treatment weeks 6 and 12. Any adverse effects due to the insecticidal treatment, however, were not considered to be environmentally deleterious in light of the restricted type of habitat (rice culture) in which the chlorpyrifos was used.

Biodegradation, Environmental↗
PubMed1976

Right ventricular volume characteristics before and after palliative and reparative operation in tetralogy of Fallot.

Right heart volume data were obtained in 63 patients with tetralogy of Fallot. The patients were divided into three groups: 1) preoperative tetralogy (N=34); 2) post shunt procedure (N=14); 3A) post repair without outflow patch (N=10); 3B) post repair with an outflow patch (N=8). In Group 1 right ventricular end-diastolic volume (RVEDV), RV ejection fraction (EF), and RV systolic output (SO) were all mildly depressed. In post shunt patients, RVEDV was normal but RVEF remained depressed. RVEDV and RVSO increased following a shunt procedure, and these variables were larger in patients with a large versus a small shunt. In Group 3A RVEDV, RVEF, and RVSO were normal. In contrast in patients in Group 3B, RVEDV was increased averaging 177 +/- 15% of normal RVEF was depressed averaging 0.45 +/- 0.04, and RVSO was normal. RV size and pump function are abnormal in patients whose operation requires an outflow tract patch and the factors which may contribute to these abnormalities include a higher RV peak pressure, pulmonary incompetence, and a larger noncontractile outflow tract. Longitudinal studies relating these variables to clinical performance and exercise testing will be important in assessment of the importance of these abnormalities.

Blood Pressure↗
PubMed1975

Inotropic effects of tolbutamide in man.

The hemodynamic responses of normal subjects to intravenous injections of tolbutamide, 250 mg., and 1,000 mg., were assessed by measurements of serial systolic time intervals. Analysis of results, compared to saline control, revealed evidence of minor inotropic effects during the period five to 10 minutes after infusion. Small but statistically significant (p less than 0.05) decreases in pre-ejection phase and electromechanical systole were noted. The time response of these changes did not correlate with dose of blood level of tolbutamide, and appeared to coincide with peak insulin levels. No inotropic or chronotropic effects were seen during the first four minutes after infusion, suggesting that the myocardial adenyl cyclase-stimulating properties of the drug, previously demonstrated in vitro, are not significant in intact man. The minor late inotropic effects are of doubtful clinical significance, and cannot be invoked to explain the reported increased cardiovascular mortality of patients treated with tolbutamide.

Adult↗
PubMed1975

Right heart volume characteristics in transposition of the great arteries.

Right and left heart volume data were obtained during 44 cardiac catheterizations in 24 patients with complete transposition of the great arteries (TGA) prior to "corrective surgery." Patients were divided into three hemodynamic groups: I)TGA with intact ventricular septum, N = 23 studies in 13 patients, ages 1 day-22 months; II)TGA with ventricular septal defect (VSD), N = 12 studies in six patients, ages 7 days-15 months; III)TGA with VSD plus pulmonary stenosis, N = 9 studies in five patients, ages 5 days-5.6 years. In group I, right ventricular end-diastolic volume (RVEDV) averaged 170 plus or minus 52% of normal (P smaller than 0.001), RV ejection fraction (EF) was 0.48 plus or minus 0.09, 74% of normal (P smaller than 0.001), and RV systolic output (SO) was 123 plus or minus 34% (NS). In group II, RVEDV was 163 plus or minus 25% of normal (P smaller than 0.001), RVEF 0.59 plus or minus 0.08, 91% of normal (NS), and RVSO was 158 plus or minus 52% (P smaller than 0.02). In group III, RVEDV averaged 124 plus or minus 26% of normal (P smaller than 0.04), RVEF 0.58 plus or minus 0.15, 89% of normal (NS), and RVSO 125 plus or minus 57% (NS). Right atrial maximal volume was increased in 21 or 22 studies and averaged 185 plus or minus 47% of normal (P smaller than 0.001). RVEDV was greater than left ventricular end-diastolic volume in all but one patient in group I, but RVEDV/LVEDV was smaller than 1.00 in four VSD patients with very large pulmonary flows. A majority of patients with TGA without VSD have abnormal right heart function as indicated by an increased RVEDV and a low ejection fraction. Longitudinal studies of right ventricular performance in these patients continue to be important in assessment of current methods of therapy.

Angiocardiography↗
PubMed1975

Importance of maximum procedure in ovarian cancer.

The maximum surgical procedure for the treatment of ovarian cancer is based on a number of sound theoretical concepts. These concepts are based on current knowledge of the biologic behavior of tumors as well as principles of chemotherapy and radiotherapy. These concepts have not been tested in a prospective randomized study. Discussed are the need for such a study and the great difficulties to be faced in achieving such a study.

Female↗