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We have compared the species richness of medicinal plants and the differential patterns of use amongst settlements in the Andean communities of Northwest Argentina which have differing levels of isolation. About 259 ethnoespecies, belonging to 74 plant families, were included, representing between 70 and 80% of the total estimate. The results indicate that Coronopus didymus is the most relevant and important species. The method of use of medicinal plants and the ailments treated by rural doctors compared to those of the layperson is different. Native and exotic plants are used differently according to the body system treated. There are some relationships between internal and external use and body systems and recipes. The greater medicinal species richness found in the less isolated locations is due to external enriching cultural influences.  相似文献   
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According to modern concepts, a malignant tumor is a complex dynamic system possessing numerous links with both the immediate environment and remote non-malignant tissues and organs. Changes in their redox balance can result in disruption of the normal tissue control. The aim of our study was to compare activity of enzymes influencing the redox state in the tumor tissue, peritumoral area, and nonmalignant tissues (taken by resection line) at various histological tumor variants. We found similar close level of reduced glutathione in the tissues of gastric adenocarcinoma and vulvar squamous cell carcinoma; however, dynamics of this parameter in the tumor surrounding tissues was different. In contrast to gastric adenocarcinoma, vulvar squamous cell carcinoma was characterized by a significant increase in glutathione content in the tumor tissue and increased activity of all investigated enzymes of the glutathione system in the tumor tissue and its peritumoral area as compared with the surrounding non-malignant tissue. These results underlie existence of clear differences in the functioning of the redox regulatory systems in the tumor and surrounding tissues of various histological origin and localization; these differences may be possibly attributed to different mechanisms involved in maintenance of the redox balance in the originally non-malignant tissues.  相似文献   
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We used heterogeneous parental cultures of AXC/SSh rat prostate cancer cells to isolate clonally derived prostate cancer cell lines. Light and electron microscopic analyses established that parental and clonally isolated cells possess features characteristic of secretory epithelium. Biochemical analyses showed that these cells contained androgen receptors and acid phosphatase and 5 alpha-reductase activity; phenotypic markers characteristic of differentiated prostate epithelium. Content of these prostate epithelial cell markers was variable and cell line specific. We used selected cell lines to examine androgen modulation of AXC/SSh rat prostate cancer cell proliferation in vitro. We found that proliferation of C-family or D-family cells, those respectively maintained on medium without additions or medium containing 10(-7) M 5 alpha-dihydrotestosterone, was not affected by changes in medium testosterone concentration through the range 10(-6)-10(-9) M. In contrast, testosterone modified proliferation of T-family cells, those maintained on medium containing 10(-7) M testosterone, and effects were antagonized by the anti-androgen RU 23908. Preliminary studies established that AXC/SSh rat prostate cancer cells elaborate polypeptide components which stimulate in vitro cell proliferation. Both the ability to elaborate these components and their effects on in vitro cell proliferation appeared to be cell line specific.  相似文献   
357.
Renal metabolism has been studied in eight dogs before and 48 hr after a 60-min period of renal ischemia induced by clamping the left renal artery with the simultaneous removal of the right kidney, and in 12 sham-operated animals. The study involved the measurement of renal uptake and production of lactate, glutamine, glutamate, alanine, ammonium, and oxygen, and the measurement of the tissue concentrations of ATP, glutamine, lactate, alpha-ketoglutarate, aspartate, and alanine in the renal cortex. Two days after a temporary renal ischemia, the remaining kidney showed a 22% decrease in glomerular filtration rate (GFR) and a 25% decrease in renal plasma flow. Fractional sodium and potassium excretions were similar to those of control dogs. Renal production or extraction of glutamine, glutamate, alanine, ammonium, and oxygen (all expressed by 100 ml of GFR) was not significantly different in basal conditions or 2 days after ischemia, but lactate extraction was reduced in postischemic kidneys (-101 +/- 29 vs -204 +/- 38 mumol/100 ml GFR in control dogs). The cortical concentrations of glutamine and glutamate were lower in postischemic than in control kidneys. No differences were found in cortical concentration of alpha-ketoglutarate, aspartate, lactate, pyruvate, or ATP, but total nucleotides and inorganic phosphate were decreased in postischemic kidneys. It is concluded that in the recovery phase of the ischemia, a decreased lactate uptake is the main metabolic change, and total ATP production is adapted to the decrease of GFR and sodium reabsorption.  相似文献   
358.
Role of NMDA receptors in the process of associative learning has been studied in the honeybeeApis mellifera L. in behavior experiments, using method of conditional reflexes. To determine pharmacological profile of NMDA receptors, effects of Mg2+ ions, NMDA, glycine (Gly), antagonist of the glycine site 5,7-dichlorokynurenic acid (DCK), competitive antagonists of NMDA receptors: D,L-2-aminophosphovalerate (APV), L-2-aminophosphobutyrate (APB), and D-glutamyl-aminomethylphosphonic acid (GAMP) as well of antagonists of NMDA receptor ion channels MK-801 and ketamine (Ket) were studied on acquisition of alimentary conditional reflex and its retention in memory. NMDA increased capacity for learning by stimulating shortterm memory. The NMDA receptor co-agonist Gly activated this NMDA effect. DCK eliminated the NMDA and Gly stimulatoty effects. All tested antagonists at millimolar concentrations inhibited associative function. The data obtained confirm our hypothesis about participation of NMDA receptors in processes of formation of short-term memory in the honeybeeApis mellifera and suggest that functional characteristics of the NMDA receptors involved in the process of associative learning in the honeybee resemble those in mammals.  相似文献   
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Electron microscopy of mouse neocortex was carried out during rehabilitation following long-term protein-caloric deficiency. Food rehabilitation led to partial recovery of brain ultrastructure, however, a high neuronal level of secondary lysosoms and lipofuscin bodies was preserved, with the changes in the spine apparatus and synaptic contacts persisting in neuropile. Carnitine addition to food during rehabilitation increased the number of free ribosomes in cortical neurons. A substantial development of granular endoplasmic reticulum was observed. A greater number of spine apparatus cisterns was detected, however, like in conventional rehabilitation, the width of synaptic clefts and postsynaptic densities remained narrower than in control mice.  相似文献   
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