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Biomedical subjects

T Tong

Publications and source records attributed to T Tong.

At least 55 records · Page 3Linked to original sources
PubMed1989

Cutaneous malignant melanoma. II. The natural history and prognostic factors influencing the development of stage II disease.

The survival history of 259 patients with Stage I cutaneous malignant melanoma who were at risk for developing regional nodal metastases (Stage II) were studied. Eighty-seven of 377 Stage I patients (23%) developed regional nodal metastases (Stage IIB) with 40% 5-year survival. Fifty patients had regional nodal metastases at presentation, with or without a known primary (Stages IIA or IIC, respectively), with a 42% 5-year survival. A step-down multivariate analysis using the Cox regression model revealed four risk factors as being highly significant for predicting a more favorable survival outcome: (1) thinner Breslow thickness (P = 0.0001), (2) pathologic Stage I disease (P = 0.004), (3) no clinical ulceration (P = 0.0004), and (4) being a woman younger than 50 years of age (P = 0.029). These results are discussed in reference to other series.

Age Factors↗
PubMed1988

Cutaneous malignant melanoma (Arizona Cancer Center experience). I. Natural history and prognostic factors influencing survival in patients with stage I disease.

The authors have studied the natural history of 377 patients with Stage I cutaneous malignant melanoma followed at the Arizona Cancer Center, Tucson. Two hundred eight patients, or 55%, remained free of metastatic disease after a median follow-up of 30 months. The survival at 5, 8, and 10 years was 69, 65, and 63%, respectively. Natural breakpoints in Breslow thickness for survival occurred at 0.85, 1.95, and 4.00 mm. These are not significantly different from those found by other investigators. A step-down multivariate analysis using the Cox regression model yielded four factors as highly significant in predicting survival: Breslow thickness (P less than 0.001), an age/sex interaction (P = 0.0012), clinical ulceration (P = 0.0039), and a prophylactic node dissection (P = 0.019). No predictive value for a BANS or non-BANS location was detected. These results are discussed in reference to other large series which describe the natural history of cutaneous melanoma.

Arizona↗
PubMed1984

Treatments for Centruroides exilicauda envenomation.

We treated two cases of severe envenomation by the scorpion Centruroides exilicauda. The first infant was treated with a species-specific scorpion antivenom, which produced a delayed but dramatic return of all vital signs to normal. A second infant was treated with two doses of intravenous propranolol hydrochloride and had a rapid, dramatic decrease in heart rate but only gradual resolution of neurologic symptoms. These cases demonstrate the severe symptoms of envenomation by this scorpion in the infant and show two possible treatments.

Antivenins↗
PubMed1984

Evaluation of an automated image analysis system for counting human tumor colonies.

The Omnicon FAS II image analysis system was applied to counting tumor colonies grown in a soft agar human tumor clonogenic assay with a detailed protocol designed to assess the instrument's sensitivity, specificity, precision, and accuracy. Comparisons of technician and instrument counts were done on a blinded basis. Sensitivity studies (which used metal microspheres) yielded a correlation coefficient (r) of 0.999 between technicians and the counter. A field-by-field analysis of the instrument's specificity for identifying individual objects correctly as tumor colonies rather than artifacts (as identified by the technician) was excellent (r = 0.95). In the precision studies (determined with repeated automated counting of the same samples for five days), the median coefficient of variation was less than 7%. Accuracy was evaluated on cultures of fresh biopsies from 30 human cancers obtained for drug sensitivity testing as well as on a series of tumor cell lines. The correlation between the mean number of colonies counted by the technicians and by the colony counter was greater than 0.91. Similar comparisons of mean percent survival of tumor colony-forming cells after drug exposure between technician and machine were also quite acceptable (r = 0.85). We conclude that the colony counter provided sufficient reliability to be applied to counting human tumor colonies grown in vitro. In addition, the colony counter performed the Petri dish counts ten times faster than experienced technicians and without associated operator fatigue.

Animals↗
PubMed1983

Use of survival analysis to determine the clinical significance of new Q waves after coronary bypass surgery.

There are few data on the long-term effects of new Q waves on survival and morbidity after coronary bypass graft surgery (CABG). We followed 1340 patients who underwent CABG in 1978 at 10 hospitals participating in the Coronary Artery Surgery Study (CASS). The incidence of perioperative Q-wave infarction was 4.76% (range 0.0-10.3% by hospital). The rate of infarction was higher in patients who had an increased left ventricular end-diastolic pressure or cardiomegaly on the preoperative chest radiograph. Patients who received more grafts or who had longer cardiopulmonary bypass time were also at higher risk of infarction. In a stepwise discriminant analysis of 44 clinical, angiographic and surgical variables, cardiopulmonary bypass time, topical cardiac hypothermia and cardiomegaly entered the stepwise selection of variables. Long-term survival was adversely affected by the appearance of new postoperative Q waves. The hospital mortality was 9.7% in the 62 patients who had new postoperative Q waves and 1.0% in the 1278 patients who did not (p less than 0.001); the 3-year cumulative survival rates were 85% and 95%, respectively (p less than 0.001). In patients who survived to hospital discharge, the presence of new postoperative Q waves did not adversely affect 3-year survival (94% and 96%, respectively). The survival rates were worse in patients who had a history of infarction or who had impaired left ventricular function preoperatively. The number of readmissions to hospital after CABG among the patients who had a transmural perioperative infarction was similar to to that among patients who did not. We conclude that the appearance of new Q waves after CABG adversely affects survival. The major impact on mortality occurs before hospital discharge. Patients who are destined to have a perioperative infarct cannot be predicted from commonly measured preoperative and angiographic variables.

Adult↗
PubMed1982

Impaired metabolism of methylphenobarbital after a combined drug overdose: treatment by resin hemoperfusion.

A 38-yr-old woman who by history ingested 13 g methylphenobarbital, alcohol, and 6 g acetaminophen became comatose slowly over 4 d. Acute hepatic injury appeared to impair the oxidative N-demethylation of methylphenobarbital to its product, phenobarbital. On the eighth day after ingestion she was treated because of protracted coma with Amberlite XAD-4 resin hemoperfusion. Hemoperfusion, which removed 0.83 g methylphenobarbital and 2.10 g phenobarbital, led to transient clinical improvement. When supportive patient management fails to produce a satisfactory clinical course in a methylphenobarbital-intoxicated patient, hemoperfusion could be a useful adjunct to therapy.

Acetaminophen↗
PubMed1981

Presystemic metabolism of meperidine to normeperidine in normal and cirrhotic subjects.

Plasma concentrations and urinary excretion of meperidine and its metabolite normeperidine were determined after intravenous and oral administration to 11 men; five men had hepatic cirrhosis and six were normal. Systemic clearance of meperidine was smaller and bioavailability and half-life greater in the cirrhotic patients than in the normal subjects. Plasma concentrations and 24-hr urinary excretion of normeperidine was lower and persistence of normeperidine in plasma longer in the patients with cirrhosis. The route of administration did not alter the fraction of normeperidine generated from meperidine. The results suggest that in patients requiring repeated meperidine dosage the drug should be taken parenterally rather than orally to allow maximal analgesia and minimal formation of normeperidine. Patients with cirrhosis may be relatively protected from normeperidine toxicity because of impaired formation, but the risk of cumulative toxicity may be greater than in normal subjects because of slower elimination of the metabolite and greater sensitivity to the effects of narcotics on the central nervous system.

Administration, Oral↗
PubMed1980

Enhanced bioavailability of pethidine and pentazocine in patients with cirrhosis of the liver.

We studied the bioavailability and disposition kinetics of pethidine and pentazocine in patients with alcoholic cirrhosis and age-matched healthy subjects. In the presence of liver disease, the bioavailability of pethidine was 31% and pentazocine 233% greater than in normals. Systemic clearance was approximately half and terminal half-life double normal for both drugs, whereas volumes of distribution were unchanged. Because of greater bioavailability, oral doses of pethidine and pentazocine should be reduced substantially in patients with cirrhosis. When multiple oral or parenteral doses are required, dosing interval should be lengthened or repeated doses reduced below initial doses because of lower systemic clearance.

Administration, Oral↗
PubMedDate not supplied

Cancer statistics, 1992.

Explore the source record for details and available documents.

Black or African American↗
PubMedDate not supplied

Cancer statistics, 1995.

The American Cancer Society's Department of Epidemiology and Statistics reports its 29th annual compilation of cancer incidence, survival and mortality data for the United States and around the world.

Adolescent↗