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Biomedical subjects

D Tierney

Publications and source records attributed to D Tierney.

8 recordsLinked to original sources
PubMed1999

Release of atrazine ((14)C) from two undisturbed submerged sediments over a two-year period.

Through water erosion and runoff, sediment-adsorbed atrazine can undergo sedimentation and accumulation at the bottom of water bodies and become potential sources of atrazine to the water column. The purpose of this study is to determine the fate and release of atrazine ((14)C) to the water column from two simulated undisturbed submerged sediments at two temperature treatments (5 and 24 degrees C) over a 2-year period. Atrazine residue ((14)C) was released from the two sediments and was, primarily, diffusing from the sediment pore water to the water columns. The amount released was affected by sediment type and is related to the sediment's adsorption/desorption capacity. Larger amounts of residue ((14)C) were released to the water columns at 5 degrees C than at 24 degrees C. Atrazine degraded in the shallow submerged anaerobic sediment's water columns over the 2-year period. Less than 2% (percent of applied in atrazine equivalent) of extractable atrazine and metabolites remained in the sediment after 2 years. The amount of nonextractable atrazine residue ((1)(4)C) was significantly higher in sediments at 24 degrees C than at 5 degrees C. In conclusion, atrazine accumulating in shallow undisturbed submerged sediments from nonpoint sources would most likely degrade and/or become nonextractable over time and would have a low probability of becoming a significant source to the water body. The conditions where accumulation and future release of atrazine have a greater potential to occur are under very cold temperatures with low adsorption capacity sediments.

Atrazine↗
PubMed1996

Two comparative endoscopic evaluations of Naprelan.

This paper describes the results of two endoscopic studies of Naprelan (Wyeth-Ayerst Laboratories, Philadelphia, Pennsylvania), a controlled-release formulation of naproxen sodium. In one study, 19 healthy male subjects received either 2 controlled release Naprelan 500-mg tablets once daily or 1 Naprosyn (naproxen; Syntex Laboratories, Inc., Palo Alto, California) 500-mg tablet BID. At baseline, all subjects had gastroduodenal endoscopy scores of 0 on both the Lanza and Euler scales. Although the trend favored Naprelan, differences in Lanza and Euler scale elevations were not statistically significant. Eight of 10 subjects in the Naprelan group and 7 of 9 subjects in the Naprosyn group reported a total of 27 adverse events (AEs). In the second study, healthy subjects received Naprelan 1,000 mg once daily, Naprosyn 500 mg BID, and film-coated aspirin 650 mg QID. In the stomach, there was a significant difference in favor of Naprelan over aspirin (P = 0.0001) and in favor of Naprosyn over aspirin (P = 0.0001). Fewer erosions were seen in the duodenum than in the stomach. In the duodenum, there was a significant difference in favor of Naprelan over Naprosyn (P = 0.0236), and in favor of Naprelan over aspirin (P = 0.0086), but the difference between Naprosyn and aspirin was not significant (P = 0.6643). Of the 23 subjects who received medication, 12 reported AEs: 8 while receiving aspirin, 3 while receiving Naprosyn, and 1 while receiving Naprelan. Differences in the number of erosions and ulcers seen following each of the periods of drug administration favored Naprelan and the Intestinal Protective Drug Absorption System.

Adolescent↗
PubMed1990

She ate not the bread of idleness: exhaustion is related to domestic and salaried working conditions among 539 Québec hospital workers.

Hospital workers completed a questionnaire on domestic and professional working conditions and health symptoms. Workers were asked to estimate the number of domestic work hours, and the degree of sharing of laundry, cleaning, meal preparation and childcare. Responses from the 532 women workers showed an average professional work week of 31.2 hours and an average domestic work week of 19.2 hours. The length of the domestic work week increased with the number of children, and the degree of sharing diminished. Among couples with children, the reported length of the domestic work week correlated highly with an index calculated from the degree of sharing of domestic tasks, and the number and ages of children. Exhaustion and insomnia were associated with work speed and shift work, respectively, at the hospital job, but also with the number of hours of domestic work. Backache, which was related to lifting weights in the workplace, was not associated with the number of reported hours of domestic work. Due to errors in formulating some questions, the study underestimates total hours of domestic work, and, probably, effects of domestic work on health. However, it is the first North American study to show the combined effects of domestic work and paid work on physical health symptoms among women.

Adult↗