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S D Kroll J Chen M De Vivo D J Carty A Buku R T Premont R Iyengar 《The Journal of biological chemistry》1992,267(32):23183-23188
3.
The effects of protein malnutrition on responsiveness of macrophages to proteosepeptone stimulation and on their chemical
composition were investigated. Relative number of resident macrophages in rat peritoneal cavity was reduced by about 50 %
during 4 weeks on 3 % protein diet. Similarly, decreased migration capacity of the circulating macrophages to the peritoneal
exudate in response to the stimulant, was observed in protein-fasted rat compared to that in the 20 % protein-fed group. Further,
the chemical composition of the isolated elicited cells was determined. Total proteins, sugars, lipids and nucleic acids were
significantly low in the cells isolated from protein-deficient animals, though the cell size was not affected. However, cholesterol:
phospholipid molar ratios were distinctly higher than that in control and increased progressively in the 3 and 8 % protein-fed
animals. The implications of these structural changes in macrophages on their functional capability are discussed 相似文献
4.
A recent study from our laboratory indicated additional tissue injury during rewarming of a cooled rabbit leg. Oxygen-derived free radicals were believed to play a role in such "rewarming injury." Since free radicals may attack membrane phospholipids, we analyzed the phospholipid composition in the leg tissue during cooling and rewarming. Our results indicated significant breakdown of membrane phospholipids, particularly phosphatidylcholine and phosphatidylethanolamine, with a corresponding accumulation of lysophosphatidylcholine and nonesterified fatty acids. Quinacrine, a phospholipase inhibitor, was able to preserve membrane phospholipids during rewarming of the cooled leg. Rewarming of cooled tissue was also accompanied by additional tissue injury, as evidenced by the increased release of lactic acid dehydrogenase and creatine kinase, as well as enhanced lipid peroxidation, as evidenced by increased malonaldehyde formation. Quinacrine reduced the release of these intracellular enzymes and decreased lipid peroxidation, suggesting its efficacy as a therapeutic agent against hypothermic injury. 相似文献
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Opiate actions on mesocortical dopamine metabolism in the rat 总被引:3,自引:0,他引:3
The actions of parenteral morphine were examined with regard to dopamine metabolism in the mesocortical dopaminergic pathways of the rat. The effects of morphine on dopamine metabolism in the prefrontal, cingulate, pyriform and entorhinal cortices were compared with the actions of morphine on the metabolism of dopamine in the striatum and olfactory tubercle. In all tissues, except the entorhinal cortex, morphine significantly elevated the dopamine metabolites dihydroxphenylacetic acid and homovanillic acid. These data, along with previous studies of various pharmacological agents, clearly indicate that the mesocortical dopaminergic projections possess unique opioid and non-opioid regulatory inputs. 相似文献
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The pre-irradiation combustion (PC) of samples to liberate iodine, followed by trapping the iodine on charcoal and quantifying
the element by neutron activation analysis (NAA), has been used at the National Institute of Standards and Technology for
the determination of iodine in biological materials. The applicability of this technique to numerous environmental and dietary
matrices is illustrated by analysis of a range of certified reference materials (CRMs) and a powdered grass material that
was prepared as an in-house reference material (RM). Because of the combustion step involved, samples with low or no fat content
(e.g., cereal products, selected botanical specimens, and nonfat milk powder) and inorganic materials (e.g., coal fly ash
and dried sediments) are more suited for analysis by this method. In general, the results for several types of samples obtained
by this method agreed with those obtained by a second radiochemical (R) NAA, as well as by a third method using inductively
coupled plasma mass spectrometry (ICP-MS). PC-NAA is a useful technique for determining iodine in biological and environmental
samples, especially for verification of iodine results obtained from other methods. 相似文献
9.
Effect of storage, photoperiod and mechanical scarification on seed germination in Ocimum americanum
Dilip Amritphale Y. K. Mukhiya J. C. Gupta Shamanta Iyengar 《Physiologia plantarum》1984,61(4):649-652
Seeds of Ocimum americanum L. display an absolute light requirement for germination. The minimal length of the daily photoperiod required to induce a high germination decreased with increasing seed age, but the length of the photoperiod under potential control of terminal far-red light inhibition remained unchanged. There was a gradual escape from the far-red inhibition with increase in the length of the photoperiod. Seeds developed flash photosensitivity after the first 13 h photoperiod. Scarification treatment did not allow the seeds to bypass the light requirement, but it enhanced the germination considerably. Under conditions of natural day length in the field, weakening of the testa by sand may abolish the need for a second exposure to light for most of the seed population, thus rendering them non-photoperiodic. 相似文献
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