Search Results

open access

The Effect of Nine Diet and Water Combinations on the Culture Health of Ceriodaphnia Dubia

Description: Culture health of Ceriodaphnia dubia was evaluated for organisms cultured using all combinations of three foods and three waters. Criteria used to assess health of cultures included adult and neonate weights, time required to produce first broods, neonate production, adult survival, and resistance to hexavalent chromium. Diet/water combinations which produced the most neonates were not found to produce adults which were more resistant to chromium than those which produced fewer neonates. Of tho… more
Date: May 1990
Creator: Patterson, Paul W. (Paul William)
open access

The Effects of Long Term Modernate Ethanol Intake on Plasma Levels of ACTH, Beta Endorphin, and Corticosterone in Rats

Description: The effects of single injections and daily oral administration of ethanol on plasma levels of ACTH, beta endorphin, and corticosterone in response to cold stress were examined. The long-term experimental animals were given 0.25 ml of 28% ethanol or water orally once a day, five days a week, for fourteen months. Plasma levels of ACTH, beta endorphin, and corticosterone were lower in alcohol-treated rats as compared with water-treated rats when exposed to cold stress. The effects of a single inje… more
Date: December 1990
Creator: Breedlove, Kenneth
open access

Opioid/Adrenergic Interaction in Regulating Canine Cardiac Function

Description: Opioid/adrenergic interactions were studied to evaluate two hypotheses: (1) naloxone potentiates the effect of epinephrine on cardiac contractility by increasing circulating epinephrine concentrations; and (2) endogenous and exogenous opioids alter left cardiac nerve stimulationinduced norepinephrine release and cardiac function. A canine isolated heart-lung preparation was used for the first study. Plasma epinephrine was determined and myocardial epinephrine uptake was calculated during intrav… more
Date: May 1990
Creator: Gu, Hong
open access

Regulation of Colony-Stimulating Factor-1 Biosynthesis

Description: Recent studies suggest that synthesis of the Colony-stimulating factor (CSF) is a well regulated process. However, the molecular mechanisms of the signal transduction of the various inducers of CSF such as monokines and lymphokines are not well understood. Using Interleukin 1 (IL-1) stimulation of CSF-1 in the MIA PaCa-2 cell line as a model system, the involvement of G-protein has been studied. The IL-1 induction of CSF-1 synthesis can be inhibited by both Pertussis toxin and Cholera toxin, wh… more
Date: May 1990
Creator: Ku, Chun-Ying
open access

Responses of Pristina leidyi Smith 1896 (Naididae: Oligochaeta) to Cadmium, Vanadium, and Some Environmental Factors

Description: Concern over sediment toxicity has increased the need for toxicity test information with organisms that inhabit sediments. Oligochaetes are exposed to toxicants through feeding and direct body contact with aquatic sediments. Chronic testing with oligochaetes has historically focused on tubificids with test lengths of one year or more to encompass several generations. Most naidid oligochaetes have generation times of three to seven days and could provide chronic information in a matter of weeks.… more
Date: May 1990
Creator: Smith, David P. (David Paul), 1956-
open access

Toxicity of Chromium and Fluoranthene From Aqueous and Sediment Sources to Selected Freshwater Fish

Description: Research efforts in aquatic toxicology have historically centered on the chemical analyses and toxic effects of waters to aquatic organisms. More recently, sediment-source toxicity has been explored, with efforts concentrated on establishing sensitive and accurate methodologies. This study focused on the toxicity of trivalent chromium, hexavalent chromium, and fluoranthene to Pimephales promelas, Ictalurus punctatus, and Lepomis macrochirus. Test fish were exposed to both water-borne and sedime… more
Date: May 1990
Creator: Gendusa, Tony C.
Back to Top of Screen