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Biomedical subjects

G Johnson

Publications and source records attributed to G Johnson.

At least 523 records · Page 29Linked to original sources
PubMed1982

Mortality risks for survivors of vascular reconstructive procedures.

Aneurysmal disease and occlusive disease may imply different risks of hastened death. In our opinion the aortoiliac site is more favorable than the femoropopliteal site in regard to the patient's age at operation and long-term survival. A follow-up study was done of 320 patients who survived aortic aneurysm repair, 212 patients who survived aortic bypass procedures, and 203 who survived femoropopliteal bypass procedures. The median ages at the time of operation were 66, 57, and 62 years, respectively. Median years of survival for the three groups were 5.8, 10.7, and 7.2 years, respectively. The difference for survival between patients with aortoiliac occlusive disease versus those with aneurysmal disease was statistically significant, as was the difference between occlusive disease in the aortoiliac segment versus the femoropopliteal segment. The difference in median survival of patients with aortic aneurysmal disease versus those with femoropopliteal disease was not significant. White men constituted the largest group of patients. When the median years of survival for different operations in white men were stratified into 5-year age groups according to age at operation, there was no significant difference between any operations within any of the age groups. (The older subgroups were too small for meaningful analysis). This suggests that the longer median survival for aortoiliac occlusive disease can be explained by the apparently younger median age at the time of operation.

Adult↗
PubMed1981

The internal mammary artery graft. Its longevity after coronary bypass.

Two hundred ninety-eight patients who received internal mammary artery (IMA) grafts were reviewed seven to nine years after surgery; 91.6% of these patients are still alive. In 29.5% of these patients there was postoperative graft visualization, and 90% of the studies were performed because of suspected graft failure. Attrition of the IMA graft was minimal. At zero to 24 months after surgery, 93.4% of grafts were patent. At 60 to 108 months 94.4% were patent and there was little, if any, evidence of atherosclerosis in the IMAs. Precise technique in preparation and anastomosis of the IMA is essential for long-term patency. For bypassing obstructive lesions, we recommend selection of the IMA (if it has sufficient size and flow) for use in the left anterior descending, large diagonal, or marginal vessel in the left coronary artery circulation.

Adult↗
PubMed1981

Oesophageal carcinoma demonstrated by whole-body nuclear magnetic resonance imaging.

The quality of the images produced by nuclear magnetic resonance (NMR) imaging has steadily improved over the past five years. Images of the head, thorax, and abdomen have clearly shown the normal anatomy. A clinical trial of NMR imaging has therefore been started in Aberdeen to assess its diagnostic accuracy and compare it with conventional radiography and other imaging technique. The first patient examined by whole-body NMR imaging had carcinoma of the oesophagus diagnosed on barium meal examination. A technetium-99m-sulphur colloid liver scan also showed hepatic metastases. NMR imaging showed a large tumour in the lower third of the oesophagus, and areas of increased proton spin-lattice relaxation time (T1) on a section through the liver corresponded with the metastases shown on the radionuclide scan. Increased areas of T1 were present in some vertebrae, and a technetium-99m bone scan confirmed the presence of bone metastases. The NMR images in this patient compared well with the images from other techniques. The continuing clinical trial may show that NMR is an accurate diagnostic aid which will complement existing techniques for diagnosing intrathoracic and intra-abdominal conditions.

Adenocarcinoma↗
PubMed1981

Routine versus selective drainage of the gallbladder bed after cholecystectomy.

A review of 367 cases of patients undergoing cholecystectomy was made to compare the complication rates and the duration of hospital stay in the patients in whom the surgeon used routine drainage of the gallbladder bed and those in whom the surgeon used drainage selectively (only in those with severe inflammatory reaction, persistent leakage or injury to the liver bed). The patients in whom selective drainage was used had a significantly lower complication rate and a shorter hospital stay. It is concluded that routine drainage adds to the morbidity of simple cholecystectomy and should not be practiced.

Adolescent↗
PubMed1981

Succinylation of hapten-protein conjugates facilitates coupling to erythrocytes by water soluble carbodiimide: preparation of stable and sensitive target cells for use in hemolytic assays.

A facile method is described for the preparation of haptenated sheep red blood cells (SRBC) for use as targets in hemolytic spot and plaque assays for the detection of anti-hapten antibody. The method involves the use of the water soluble 1-ethyl-3-(3-dimethyl-aminopropyl)carbodiimide (EDCI) as a reagent to couple hapten-succinyl-rabbit serum albumin conjugates to SRBC. The presence of the succinyl groups on such conjugates is shown to increase the efficacy of the resulting target cells, presumably by acting as a substrate for the EDCI and thus increasing the extent of coupling to SRBC.

Animals↗
PubMed1981

Post-translation modification of xanthine dehydrogenase in a natural population of Drosophila melanogaster.

Second chromosomes of D. melanogaster were isolated from a single natural population, and 40 were analyzed by gel-sieving electrophoresis for the presence of polymorphic loci on chromosome 2 that act to modify xanthine dehydrogenase and/or aldehyde oxidase, whose structural genes map to chromosome 3. Clear evidence of polymorphism for one or more xanthine dehydrogenase modifier loci was obtained.

Aldehyde Oxidoreductases↗
PubMed1981

Recanalization of a saphenous vein interposition venous graft.

A patient is reported with successful clinical recanalization of a thrombosed saphenous vein interposition graft in the superficial femoral vein after civilian injury. Primary repair of venous injuries may prevent both initial acute venous hypertension as well as the development of chronic venous insufficiency.

Adult↗
PubMed1981

Oligodendroglial glycerophospholipid synthesis: incorporation of radioactive precursors into ethanolamine glycerophospholipids by calf oligodendroglia prepared by a Percoll procedure and maintained in suspension culture.

Oligodendroglia prepared from minced calf cerebral white matter by trypsinization at pH 7.4, screening, and isosmotic Percoll (polyvinylpyrolidone-coated silica gel) density gradient centrifugation survived in culture on polylysine-coated glass, extending processes and maintaining phenotypic characteristics of oligodendroglia. In the present study, ethanolamine glycerophospholipid (EGP) metabolism of the freshly isolated cells was examined during short-term suspension culture by dual label time course and substrate concentration dependence experiments with [2-3H]glycerol and either [1,2-14C]ethanolamine or L-[U-14C]serine. Rates of incorporation of 3H from the glycerol and of 14C from the ethanolamine into EGP were constant for 14 h. In medium containing 3 mM-[1,2-14C]ethanolamine and 4.8 mM-[2-3H]glycerol, rates of incorporation of 14C and 3H into diacyl glycerophosphoethanolamine (diacyl GPE) were similar. Under the same conditions, 3H specific activities of alkylacyl GPE and alkenylacyl GPE were much lower than 14C specific activities, likely as a result of the loss of tritium during synthesis of these forms of EGP via dihydroxyacetone phosphate. L-[U-14C]serine was incorporated into serine glycerophospholipid (SGP) by base exchange rather than de novo synthesis. 14C from L-[U-14C]serine also appeared in EGP after an initial lag period of several hours. Methylation of oligodendroglial EGP to choline glycerophospholipid (CGP) was not detected.

Animals↗
PubMed1981

Outcome of irregularly discharged psychiatric patients.

Clinicians' attitudes about the posthospitalization outcome of patients who are irregularly discharged from the hospital (i.e., against medical advice or AWOL) have been pessimistic, but unsystematic follow-up data of such patients compared with regularly discharged patients suggest that outcomes for the two groups are similar. Because of this discrepancy, the authors used data from a controlled, systematic study of a large sample of voluntary inpatients that measured global outcome over 2 years. Their findings suggest that 1 year and 2 years after admission, most patients who were irregularly discharged had outcomes similar to those of patients with regular discharges. There was, however, a subgroup of irregularly discharged patients who had worse outcomes.

Humans↗
PubMed1981

Cutaneous T cell lymphoma (mycosis fungoides) in blacks.

Between 1954 and 1980, 11 patients with cutaneous T cell lymphoma (mycosis fungoides) were diagnosed at the Howard University Hospital. There were five males and six females, all of whom were black. In association with the cutaneous T cell lymphoma, six cases of poikiloderma atrophicans vasculare were demonstrated.

Black or African American↗