Search PubMed⌕ Search

Biomedical subjects

R B Smith

Publications and source records attributed to R B Smith.

At least 343 records · Page 19Linked to original sources
PubMed1979

Replacement of the ureter by small intestine: clinical application and results of the ileal ureter in 89 patients.

Partial or total replacement of the ureter by small intestine was performed at the University of California/Los Angeles Hospital and affiliated hospitals 94 times in 92 patients from 1954 to 1978. Indications included recurrent calculi, ureteral stricture, fistula, congenital obstruction of the ureter and ureteral carcinoma with a solitary kidney. A special use has been for undiversion of an ileal conduit. Followup evaluation was possible in 95% of the patients and ranged from 6 months to 23 years. Thirty-six patients were followed for more than 5 years. The operation was judged successful in 81% of the cases. Serum creatinine was unchanged or decreased in 75.7% and the pyelogram was unchanged or showed decreased dilatation in 84.6% of the patients. Although reflux was seen in 40 of 55 patients who had cystograms 39 (97.5%) were considered to be treated successfully. Indications for and results of the operation are discussed. The procedure is recommended as optimal therapy for carefully selected situations when the normal urinary tract cannot be used.

Child↗
PubMed1979

Vascular access for cancer chemotherapy.

A persistent problem in caring for patients receiving long-term intravenous chemotherapy for cancer is the maintenance of access to the vascular system. At Emory University Hospital between January 1975 and December 1977, 48 cancer chemotherapy patients had upper-arm bovine arteriovenous fistulas created for vascular access. The heterografts were inserted from the distal brachial artery to the proximal brachial vein under local, regional block, or general anesthesia. Grafts were functioning satisfactorily in 81% of the subjects at the time of death or at termination of treatment. The mean duration of useful graft patency for the entire group was 4.6 months, with a range of 0 to 27 months. Thrombosis of the graft was the most frequently encountered complication; infection and bleeding occurred infrequently. Reoperation was required in 35% of grafts, of which one half were salvaged. No mortality was attributable to the operative procedures or to the presence of a chronic arteriovenous fistula.

Arteriovenous Shunt, Surgical↗
PubMed1979

Pharmacokinetics of hepatobiliary imaging agents in rats: concise communication.

The distribution and elimination kinetics of Tc-99m pyridoxlidene glutamate (Tc-99m PG), of Tc-99m N-(2,6-dimethyl-phenylcarbamoylmethyl) iminodiacetic acid (Tc-99m HIDA), and of I-131 rose bengal in blood were quantitated after i.v. injection in rats. This was performed by use of a unique indwelling catheter that externalizes the systemic circulation, permitting continuous monitoring of blood radioactivity. The blood activity-time curves of Tc-99m PG and Tc-99m HIDA are described by the sum of three exponential functions. Only two exponentials are required in the case of I-131 rose bengal. The rank order for the rates of loss from blood was Tc-99m HIDA less than Tc-99m PG less than I-131 rose bengal. Bile was collected after administration of Tc-99m HIDA and Tc-99m PG. The total excretion of radioactivity over a 70-min period amounted to 95.7% and 42.8% of the dose of Tc-99m HIDA and Tc-99m PG, respectively. A linear compartmental kinetic model was developed to account for the disappearance from blood and the biliary excretion of these radiopharmaceuticals in rats.

Animals↗
PubMed1978

Pharmacokinetic considerations in exchange transfusion in neonates.

Neonates undergoing blood exchange often receive concomitant therapy. Questions may be raised whether dosage regimen alterations are necessary to replace drug lost as a result of the exchange procedure. Our study reports the changes in plasma concentration of kanamycin during an exchange transfusion and a pharmacokinetic analysis of the effect of the exchange on drug elimination. The relationships of the volumes of distribution, elimination rate constant, and time after dosing on the fraction of the dose eliminated in the blood exchange are developed on the basis of a one-compartment body model. Computer simulations using the equations developed were used to estimate the fraction of a dose that might be removed as a result of an exchange transfusion. As the disposition rate constant or the apparent volume of distribution increase, i.e., the clearance of the drug increases, the fraction of the dose removed by the exchange process decreases. Thus, significant amounts of drug removal may occur in an exchange transfusion for drugs with low clearance when the exchange is initiated early in the drug dosing interval. In our study, only 3% of the kanamycin dose was removed as a result of the exchange process, and dosing adjustment would not be required. This was in part due to initiation of the exchange late in the dosing interval, although the maximum calculated percentage of the dose which could have been removed under the exchange conditions employed was only 10%.

Exchange Transfusion, Whole Blood↗
PubMed1978

Pentobarbital absorption from capsules and suppositories in humans.

Serum pentobarbital levels following administration of the sodium salt as a 100-mg capsule orally and as two 120-mg suppository formulations (A and B) rectally were measured. From these data and previously determined kinetic constants after intravenous administration, the absorption rates and bioavailability of pentobarbital from each dosage form were determined. All three dosage forms were 100% absorbed. Peak serum pentobarbital levels occurred at 1, 4, and 10 hr for the capsule, Suppository A, and Suppository B, respectively. In vitro studies agreed with the serum data in that Suppository A released drug in an in vitro aqueous pH 1.4 system at a much greater rate that Suppository B. The capsule and Suppository A both appeared to be absorbed by simple first-order processes; however, Suppository B had a complex absorption pattern, which was modeled using sequential zero-order and first-order absorption.

Administration, Oral↗
PubMed1978

Traumatic hemipelvectomy--the tenth survivor: a case report and a review of the literature.

This tenth survivor of traumatic hemipelvectomy was a young male involved in a collision between a car and his bicycle. As in previous cases, he sustained severe associated injuries to the genitourinary tract and rectum. Atypically he required secondary closure with autogenous skin taken from the severed lower limb, and in addition, he developed a compartment syndrome in the opposite leg.

Accidents, Traffic↗
PubMed1978

The natural history of metastatic renal cell carcinoma: a computer analysis.

Survival factors of 86 patients with metastatic renal cell carcinoma were studied by computer analysis. Cumulative survival was 53 per cent at 6 months, 43 per cent at 1 year, 26 per cent at 2 years and 13 per cent at 5 years. Survival was influenced favorably by confinement of metastases to the lungs, by the absence of local recurrence or persistence of tumor and by a longer interval free of disease after removal of the primary tumor. Medical therapy improved survival during the first year after diagnosis of metastases but no objective regression of tumor was observed. Excision of metastatic foci significantly improved survival for up to 5 years (p less than 0.05 and p less than 0.02) after which most patients died of recurrence. Palliative or adjunctive nephrectomy in patients with metastases was associated with a 6 per cent mortality rate but it increases survival over other patients with metastases at the time of diagnosis of renal carcinoma who did not undergo nephrectomy. This difference was owing to patient selection and survival of those who had adjunctive nephrectomy was no greater than that of the study population as a whole. However, based on the factors that were associated with improved survival palliative nephrectomy may be beneficial when a limited number of metastases treatable by excision or radiation therapy are present, when effective systemic therapy exists or when the primary tumor produces severe symptoms.

Adenocarcinoma↗
PubMed1978

Levamisole in the treatment of non-invasive and invasive bladder cancer: a preliminary report.

We have done a double-blind, randomized, controlled study on 37 patients with transitional cell carcinoma in which levamisole was used as an immune adjuvant in addition to the standard therapy for non-invasive and invasive bladder cancer. Levamisole is administered easily and is well tolerated, especially when compared to other immune adjuvants, such as bacillus Calmette-Guérin or Corynecbacterium parvum. Recall antigens, dinitrochlorobenzene reactivity and total lymphocyte count demonstrated little correlation to the initial stage of disease. Monocyte chemotaxis was increased significantly in patients receiving levamisole. Since our study is ongoing on data exist as yet to make any statement regarding the efficacy of levamisole in the treatment of bladder cancer.

Aged↗
PubMed1978

A randomized, controlled trial of the distal splenorenal shunt.

In 1971 a prospective, randomized trial was initiated to determine efficacy of the distal splenorenal shunt in the management of cirrhotic patients who had previously bled from esophageal varices. When entry into the trial was terminated in 1976, 26 patients had received the distal splenorenal shunt (selective) and 29 had undergone a nonselective shunting procedure (18 interposition mesorenal, six interposition mesocaval, and five other nonselective shunts). Three operative deaths occurred in each group. Early postoperative angiography revealed preservation of hepatic portal perfusion in 14 of 16 selective patients (88%), but in only one of 20 nonselective patients (5%; p < .001). Quantitative measures of hepatic function (maximal rate of urea synthesis or MRUS and Child's score) were similar to preoperative values in the selective group but were significantly decreased in nonselective patients on the first postoperative evaluation (p < .001 for MRUS; p < .05 for Child's score). Eighty-seven per cent of selective and 81% of nonselective patients have now been followed for three to six years since surgery. Late postoperative evaluation of 29 survivors (12 selective, 17 nonselective) still shows an advantage to the selective group with respect to MRUS, Child's score, and incidence of hepatopetal portal blood flow, but differences are no longer statistically significant. However, if the seven patients with portal flow (five selective; two nonselective) are compared to the 20 with absent portal flow (seven selective; 13 nonselective), the former group has significantly higher values for MRUS (p < .05) and Child's score (p < .025). No patient with continuing portal perfusion has developed encephalopathy as compared to a 45% incidence of this complication in individuals without portal flow (p < .05). No significant differences between selective and nonselective groups have appeared with respect to total cumulative mortality (ten selective; 38%; eight nonselective, 28%), shunt occlusion (two selective, 10%; five nonselective, 18%), or recurrent variceal hemorrhage (one selective, 4%; two nonselective, 8%). Overall, significantly fewer selective patients have developed postoperative encephalopathy (three selective, 12%; 15 nonselective, 52%; p < .001). Therefore, we conclude that the distal splenorenal shunt, especially when its objective of maintaining hepatic portal perfusion is achieved, results in significantly less morbidity than nonselective shunting procedures.

Alcoholism↗
PubMed1978

Magnesium: not essential for renal preservations by initial perfusion and hypothermic storage.

Experimental observations regarding the role of divalent magnesium ion in hypothermic renal preservation have presumed the inclusion of this substance in synthetic preservation media. Retrospective analysis of the validity and application of these experimental data and consideration of the problems related to precipitation of magnesium salts in "intracellular" perfusates has instigated investigation related to the necessity of including this ingredient in our previously described hyperosmolar intracellular electrolyte solutions. Omission of magnesium chloride from these perfusates has not adversely affected ultimate renal function in canine kidneys preserved for 2 and 3 days following perfusion and storage in these solutions. The absolute necessity of including magnesium in these solutions in order to effect successful renal preservation is challenged.

Animals↗
PubMed1978

Preliminary report of the use of levamisole in the treatment of bladder cancer.

Sixty-two patients with transitional cell carcinoma have been admitted to a double-blind randomized control study with levamisole as an immune adjuvant, in addition to standard therapy for noninvasive and invasive bladder cancer. Levamisole has been shown to be easily administered and is well-tolerated, especially when compared to other immune adjuvants such as bacillus Calmette-Guerin or Corynebacterium parvum. To date, there is no significant difference in the disease-free interval in the levamisole-treated group compared to the placebo group. Initial dinitrochlorobenzene (DNCB) reactivity may be an important prognostic indicator with regard to tumor recurrence. Tumor recurrence seems to be rare in those patients who are initially DNCB-positive. Total monocyte count, T lymphocyte, FC receptor cells, and PHA response showed no improvement with levamisole therapy. Monocyte chemotaxis remains the only immune function study to improve with levamisole, but the clinical significance of this test is yet to be explained.

Carcinoma, Transitional Cell↗
PubMed1978

Preoperative aortography before abdominal aortic aneurysmectomy?

A review of 100 consecutive patients undergoing abdominal aortic aneurysmectomy was made to assess the value and necessity of preoperative aortography. Comparison of arteriography with physical examination, plain roentgenograms and ultrasonography suggests that angiography is required only for evaluation of specific problems. Indications for the selective use of preoperative aortography are proposed.

Aneurysm↗
PubMed1978

Pathophysiology of acetaminophen overdosage toxicity: implications for management.

Acute acetaminophen intoxication was studied in the dog to characterize pathogenesis and in the mouse as a model for antidotal research. In the dog, overt toxicity was manifested principally by cyanosis, facial and paw edema, gastrointestinal disturbance, and coma. Typical laboratory findings were methemoglobinemia, hemoconcentration, leukocytosis, and hepatic centrolobular necrosis. In the mouse, physical signs of acetaminophen overdose appeared to be central in origin; sequelae included anemia, leukopenia, thrombocytopenia, and hepatic centrolobular necrosis. The antidotal profile of acetylcysteine in mice was characterized. When acetylcysteine therapy was instituted early (one hour after acetaminophen overdose), it conferred dose-related protection from lethality coupled with hepatoprotection, as judged from transaminase activity. When acetylcysteine therapy was instituted relatively late (4 1/2 hours after acetaminophen overdose), its beneficial effect on survival persisted but was unaccompanied by distinct hepatoprotection, indicating that SGPT activity was an unreliable prognostic indicator. Acetylcysteine was well tolerated in mice even when administered in the presence of preexisting acetaminophen-induced liver damage.

Acetaminophen↗