排序方式: 共有3条查询结果,搜索用时 0 毫秒
1
1.
SA Ridley PS Chrispin H Scotton J Rogers D Lloyd 《Canadian Metallurgical Quarterly》1997,52(3):195-202
Fourteen male rats were trained to discriminate between injections of 2 mg/kg delta-9-tetrahydrocannabinol (delta 9-THC) and vehicle in a 2-lever operant drug-discrimination paradigm. Following training, substitution tests using a cumulative dosing procedure revealed that anandamide (0.5-16 mg/kg ip), the putative endogenous camabinoid receptor ligand, failed to generalize to the discriminative stimulus properties of the training dose of delta 9-THC. However, dose-dependent generalization to the delta 9-THC cue was observed following administration of both CP-55,940 (0.05-0.8 mg/kg ip), a synthetic cannabinoid, and (R)-methanandamide (0.5-8 mg/kg ip), a metabolically stable analog of anandamide. Collectively, these results demonstrate a cannabinoid-specific in vivo effect of an anandamide compound and suggest that the naturally occurring form of anandamide may be metabolized too rapidly to produce a cannabimimetic intercceptive state when administered peripherally. 相似文献
2.
David M. Onyango Paul S. Orina Rose C. Ramkat Chrispine Kowenje Cecilia M. Githukia Dorcas Lusweti Henry B. O. Lung'ayia 《Lakes & Reservoirs: Research and Management》2020,25(3):350-361
Microcystins are part of algal toxins produced intracellularly within algal cells, being in the family of hepatotoxic cyclic peptides from various species of blue‐green algae. Blue‐green algae are widely abundant in many equatorial eutrophic lakes, including Lake Victoria, with microcystin mainly from cyanobacterial blooms released into the water column, with different effects along the aquatic ecosystem trophic levels. Depending on the length of exposure and exposure route, microcystin effects on fish can include embryonic hatching perturbations, reduced survival and growth rates, changes in behavior, osmoregulation, increased liver activities and heart rates, as well as histopathological effects. While bioaccumulation is confirmed among fish, biomagnification along food webs is debatable. Lake Victoria the second largest freshwater lake in the world, and the source of livelihoods to millions reported near the gulf and shore MCs of 190 ± 51 to 543 ± 26 ng MC/g DW, respectively. Little is known, however, on the effects of microcystin on the Lake Victoria fishery and, ultimately, on the human population against the WHO recommended human microcystin intake levels of 0.04 µg/kg, thereby being the basis for this review. 相似文献
3.
Wilfrida Nyanduko Nyairo Yasin Ramazan Eker Chrispin Kowenje Ilker Akin Haluk Bingol Ali Tor 《分离科学与技术》2018,53(10):1498-1510
Polypyrrole coated oxidized multiwalled carbon nanotubes (oMWCNT/Ppy) were applied to determine the adsorption characteristics of Pb(II) and Cu(II) from their aqueous solutions. Structural and morphological characterization studies using scanning electron microscopy, thermogravimetric analysis, Fourier transform infrared and Raman spectroscopy showed successful preparation of the oMWCNT/Ppy composite. The influence of pH, contact time, and initial metal ion concentration on the adsorption of Pb(II) and Cu(II) was studied. The adsorption processes fitted well with Langmuir isotherm and pseudo-second-order kinetic models. The maximum adsorption capacities for Pb(II) and Cu(II) were determined as 26.32 and 24.39 mg/g, respectively. Desorption studies indicated that the oMWCNT/Ppy composite could be reused for five cycles with minimum loss of its initial adsorption capacity. 相似文献
1