Search PubMed⌕ Search

Biomedical subjects

W R Johnson

Publications and source records attributed to W R Johnson.

At least 73 records · Page 4Linked to original sources
PubMed1982

Lymphocyte fluorescence polarization changes after phytohemagglutinin stimulation in the diagnosis of colorectal carcinoma.

A lymphocyte fluorescence polarization test that measures reactivity to phytohemagglutinin (PHA) has permitted discrimination of a majority of patients with colorectal carcinoma from noncancer individuals. The test involves separation of two lymphocyte fractions from 20 ml venous blood on a modified leukocyte separation gradient, incubation with PHA for 45 minutes, addition of fluorescein diacetate, and analysis of change in fluorescence polarization. Of 19 colorectal patients tested preoperatively, 13 had a positive stimulation index, 3 a zero index, and 3 a negative index. Of 7 patients with other malignant neoplasms, a positive value was obtained in 6 and a negative value in 1. Of 14 patients with other diseases, a negative value was obtained in 9, zero in 3, and positive in 2. Of 31 normal donors a negative value was obtained in 27, zero in 2, and weak positive in 2. This rapid test promises to develop into a useful cancer-diagnostic method, and elucidation of its biological basis should identify a new cancer marker.

Adult↗
PubMed1981

Prevention of wound infection in elective colorectal resections by preoperative cephazolin with and without metronidazole.

Fifty patients were admitted to a prospective controlled double blind trial for assessment of the effect of preoperative intramuscular cephazolin with oral metronidazole or placebo on the incidence of wound infection in patients requiring treatment by elective large intestinal resection. All patients were operated upon by one surgeon. After exclusion of two patients who died postoperatively 48 were analysed. No wound infection occurred in 22 patients receiving cephazolin with metronidazole. One (3.8%) infection developed in 26 patients receiving cephazolin with placebo. The difference did not attain statistical significance. Preoperative intramuscular cephazolin with or without metronidazole provides an effective and safe method of chemoprophylaxis for elective colorectal resection.

Adolescent↗
PubMed1981

Small-intestinal obstruction following resection for carcinoma of the rectum.

The incidence of small-intestinal obstruction requiring surgical relief following resection for a single carcinoma of the rectum in 1061 patients is reviewed. Forty-eight patients (4.7%) required surgical relief. There were no postoperative deaths. In 18 patients small-intestinal obstruction occurred within the first six weeks of resection. Each obstruction was related to postoperative complications, especially intraabdominal sepsis. In 30 patients the obstruction developed after this period and was due to bands and/or adhesions. The majority occurred within the first two years. The incidence of intestinal obstruction was similar after both curative and palliative resection. Extensive pelvic dissection did not influence the incidence. The paracolostomy lateral space was not closed in patients treated by abdominoperineal excision. There was no incidence of paracolostomy obstruction.

Female↗
PubMed1981

Surgery for constipation.

Over a period of 30 years a total of 27 patients have been subjected to partial or complete colectomy and anastomosis for constipation. Patients fall into four groups: (i) functional constipation; (ii) adult megacolon; (iii) megasigmoid and (iv) persistent Hirschsprung's disease. The first two groups comprised 17 patients with resistant constipation, with or without megacolon or dolichocolon. Seven (41%) of these patients subsequently required operation for acute small-bowel obstruction due to adhesions. In two patients a permanent ileostomy was necessary for persistent rectal inertia after colectomy. The functional results in these first two groups were good. The third and fourth groups had similar presenting features; five had megasigmoid, and in these resection of the sigmoid colon gave good results. The remaining five patients with proven Hirschsprung's disease responded well to a pull-through resection (4) and to colectomy and anastomosis (1).

Adolescent↗
PubMed1981

Numerical simulation of blood and plasma flow through the Petschek flow chambers.

The Stagnation Point Flow Experiment is a popular means for studying blood-surface interactions in a surface strain rate gradient. The strain rate distribution on the test surface of the flow chamber used in this experiment was originally assumed to be simply proportional to the radial distance from the stagnation point. A numerical simulation of the flows through the five most frequently used chambers shows that this is true only for one of the chambers, approximately so for another, and not true for the other three. An additional numerical simulation indicates the blood should purge the saline priming liquid within a few seconds at the beginning of the experiment.

Artificial Organs↗
PubMed1980

Abdominoperineal levator ani repair for rectal prolapse: technique.

A review some twenty years ago of the then popular rectosigmoidectomy for complete rectal prolapse having shown an excessive recurrence rate and a high incidence of incontinence, it was felt essential to seek for a more satisfactory and reliable surgical procedure for its management. This was achieved in the form of an operation, carried out from above and below, approximating the levator ani anterior to the rectum. This has given very much more satisfactory results, and is described in detail in this paper.

Adult↗
PubMed1980

Postrectal neoplasms and cysts.

The postrectal space is extensive and is in relationship to the sacral promontory and sacrum above and the coccyx below. Any of the structures in or adjacent to the space may be involved by or give rise to a postrectal neoplasm. In addition, a group of congenital neoplasms and cysts may also present in this space. Uhlig and Johnson in 1975 reviewed patients presenting to hospitals in the Portland, Oregon, U.S.A. area over a 25-year period. The population of Oregon in 1970 was 379,000. A total of 63 cases were reported. These tumours and cysts are an uncommon problem.

Adult↗
PubMed1980

The effect of Coumadin upon thrombus forming on foreign surfaces.

Experience with the Stagnation Point Flow Experiment has revealed the earliest microscopic events surrounding thrombus inception and growth on foreign surfaces in a perfectly defined flow field. Using 40 and 80 X magnification, the effects of Coumadin upon these events was studied. These events include leukocyte adherence, fibrin deposition and platelet aggregation, deviation of flow streamlines around these aggregates, and subsequent downstream thrombus growth. Surface density of leukocytes was measured as a function of time and shear, and served as an index of the quantity of thrombus on the surface, which in turn, allowed direct comparisons of thrombus growth rate between experiments. Coumadin decreases the adhesive force between leukocytes or thrombi and the foreign surface. Emboli are more frequent with Coumadin, but are smaller. Thrombus inception is not altered. These results suggest that clinical benefit obtained from use of Coumadin derives from reduction in size of emboli.

Adhesiveness↗
PubMed1980

Enhancement of thrombus formation by vascular prostheses.

The stagnation point flow experiment has been used to identify the microscopic events that occur in thrombus formation on foreign surfaces. In this investigation it was used to study the role of vascular grafts in preactivating blood, as well as the role of pretreatment of these grafts to remove the gas nuclei. The experiment was carried out under two conditions: (a) in which whole blood was led from the carotid artery of a dog to the undersurface of a microscope coverslip (control experiment) and (b) in which blood flowed from the left carotid artery of the dog through a 10-cm vascular graft to the right carotid artery and finally to the flow chamber for visualization. The thrombus morphology, time to thrombus formation and thrombus adhesiveness to the foreign surfaces were compared using knitted Dacron, woven Dacron, expanded polytetrafluoroethylene (PTFE) and saphenous vein grafts. Blood led through the vascular grafts showed a marked predisposition to thrombus formation, with no change in clotting times. Knitted Dacron most highly preactivated the blood, while PTFE showed a lesser degree of preactivation. Treating expanded PTFE so that it may be completely wetted eliminated any activation of blood and caused blood to behave as if it had not contacted a foreign surface. It was the only graft material, including autogenous vein to demonstrate this property. Therefore, of the materials tested, hydrophobic Teflon with no entrapped gas appears blood compatible.

Animals↗
PubMed1978

The treatment of carcinoma of the stomach.

A personal series of 200 patients with carcinoma of the stomach have been reviewed. Approximately 30% were regarded as suitable for curative resection; approximately 30% of the patients who underwent curative excision, survived five years; and approximately 30% surviving five years died of the disease before the 10th year. There were no early endoscopically diagnosed tumours in this series.

Carcinoma↗