Biomedical subjects
Publications and source records attributed to G D Webster.
A rational approach to problems with the Scott artificial urinary sphincter is presented, which includes preoperative radiographic, endoscopic and urodynamic studies, and intraoperative electrical testing of device integrity and pressure/volume characteristics of the system.
We performed 22 full thickness skin graft urethroplasties for treatment of urethral stricture disease or hypospadias. Excellent results were achieved in 18 cases in which a penile skin donor site was used. Three failures occurred in 4 cases in which the full thickness graft was raised from the inner aspect of the upper arm. These results suggest caution when extrapenile skin is used for such repairs.
Explore the source record for details and available documents.
This study compares the reliability, validity, and efficiency of three multiple-choice question (MCQs) ability scales with patient management problems (PMPs). Data are from the 1980, 1981, and 1982 American Board of Internal Medicine Certifying Examinations. The MCQ ability scales were constructed by classifying the one best answer and multiple-true/false questions in each examination as measuring predominantly clinical judgment, synthesis, or knowledge. Clinical judgment items require prioritizing or weighing management decisions; synthesis items require the integration of findings into a diagnostic decision; and knowledge items stress recall of factual information. Analyses indicate that the MCQ ability scales are more reliable and valid per unit of testing time than are PMPs and that clinical judgment and synthesis scales are slightly more correlated with PMPs than is the knowledge scale. Additionally, all MCQ ability scales seem to be measuring the same aspects of competence as PMPs.
Urinary frequency, urgency, bladder discomfort, and incontinence are among the most common causes for women to seek urologic evaluation. The value of endoscopy and radiographic studies is limited because they define only structural problems. This study presents 325 women who, in addition, underwent multifunction urodynamic study to identify functional problems. The merits and role of this investigation in the workup of this population group is discussed, together with the therapeutic implications of the various results.
Controversy surrounds the management of prostatomembranous urethral injuries. We herein present 38 patients and review the findings of 538 in 19 reported series. Results indicate a high risk of stricture, impotence and incontinence if conventional early urethral realignment techniques are used. Therefore, it is suggested that this approach be reserved for cases demanding immediate intervention (high riding bladder, associated rectal tear, concomitant bladder neck injury or continued bleeding), and that all others be managed by initial suprapubic cystostomy alone and delayed urethroplasty. Urethroplasty selection is discussed.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Ten male patients with posterior urethral strictures secondary to trauma of the pelvis were treated with a one stage perineal repair, consisting of excision of the strictured segment and direct anastomosis between the bulbous urethra and the apex of the prostate. Repair was performed after an interval from trauma ranging from three months to 22 years. The mean followup time was 22 months. Excellent results were observed in eight patients, diffuse distal urethral narrowing in one patient and recurrent stenosis requiring further repair in another patient. Continence and potency were unaffected. This technique is applicable to the majority of posttraumatic posterior urethral strictures, less than 2 centimeters in length, and does not preclude further repair.
Explore the source record for details and available documents.
We discuss 7 cases of the primary megacystis syndrome to demonstrate that the syndrome is non-obstructive and non-neurogenic, and probably of psychogenic origin owing to learned dysfunctional voiding. The major complication is vesicoureteral reflux and initial therapy is aimed at its correction. Prolonged followup and retraining of voiding habits are necessary. Specific pharmacologic or biofeedback techniques are indicated should urodynamic abnormalities of function be evident.
Explore the source record for details and available documents.
The polypeptide composition of the B-800-850 light-harvesting pigment-protein complex from Rhodopseudomonas sphaeroides has been determined. The complex consists of equimolar amounts of two small polypeptides. The two polypeptides have very similar molecular weights and amino acid composition but are clearly separable by eithr SDS polyacrylamide gradient gel electrophoresis or isoelectric focussing.
Mild proteolysis of Rhodopseudomonas capsulata chromatophores results in a parallel loss of the 800 nm bacteriochlorophyll absorption band a blue shift in the carotenoid absorption bands associated with the B-800-850 light-harvesting complex. Both the light-induced and the salt-induced electrochromic carotenoid band shift disappear in parallel to the loss of the 800 nm bacteriochlorphyll absorption upon pronase treatment of chromatophores. During the time required for the loss of the 800 nm bacteriochlorophyll absorption and the loss of the electrochromic cartenoid band shift photochemistry is not inhibited and the ionic conductance of the membrane remains very low. We conclude that the carotenoid associated with the B-800-850 light-harvesting complex is the one that responds electrochromically to the transmembrane electric field. Analysis of the pigment content of Rps. capsulata chromatophores indicates that all of the carotenoid may be accounted for in the well defined pigment-protein complexes.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Video urodynamics is a technique utilizing synchronously recorded urodynamic studies and custourethrography for the evaluation of complex lower urinary tract problems. The technique and equipment used in approximately 900 consecutive studies is reported. The value of this method in the investigation of urinary incontinence, complex bladder outlet obstructive states, and neurogenic bladder in particular is presented.