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31.
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Astrocytes, the most abundant cell population in the central nervous system (CNS), are essential for normal neurological function. We show that astrocytes are allocated to spatial domains in mouse spinal cord and brain in accordance with their embryonic sites of origin in the ventricular zone. These domains remain stable throughout life without evidence of secondary tangential migration, even after acute CNS injury. Domain-specific depletion of astrocytes in ventral spinal cord resulted in abnormal motor neuron synaptogenesis, which was not rescued by immigration of astrocytes from adjoining regions. Our findings demonstrate that region-restricted astrocyte allocation is a general CNS phenomenon and reveal intrinsic limitations of the astroglial response to injury.  相似文献   
33.
ABSTRACT:   Incidental catches in pelagic longline fishing pose a serious threat to sea turtle populations throughout the world's seas and oceans. In this work, carried out in the framework of the EC-DG-Fisheries 98/008 project, information on sea turtle catch rates from swordfish and albacore longline fishing activities observed in Italian waters off the Ionian Sea during 1999 and 2000, are reported. In addition, biometric data, health status, and tagging return rate of sea turtles captured are provided. A total of 200 sea turtles were caught (198 loggerhead turtles and 2 green turtles), comprising 0.5–15.7% of the total catch in number of individuals. The estimates of the sea turtles caught by the total fishing effort of both longlines in the whole study area were 1084 specimens in 1999 (95% CI = 667–1502) and 4447 specimens in 2000 (95% CI = 3189–5705). Although all sea turtles were released alive, nearly half of them had hooks that could not be removed and remained deeply embedded in the digestive tract.  相似文献   
34.
Ochratoxin A (OTA), is a nephrotoxic mycotoxin present in wine, which is nephrotoxic in humans. Our working hypothesis is that natural substances in wine may counteract OTA toxicity. Thirty-six rats were randomized to OTA dissolved in saline, red wine, or 13.5% ethanol or to OTA-free wine, ethanol, or saline. OTA (289 microg/kg of body weight/48 h) was administered by gastric gavage for 2 weeks. Serum creatinine, tubular enzymuria, renal lipohydroperoxides (LOOH), reduced (GSH) and oxidized (GSSG) glutathione, and renal superoxide dismutase activity (SOD) were determined in renal tissue. OTA alone produced significant increases in renal lipoperoxides and significant decreases in SOD and GSH/GSSG ratio. In red wine or ethanol, OTA was less nephrotoxic, reducing oxidative damage as revealed by LOOH. In OTA-wine and OTA-ethanol groups, SOD activity was higher than in the OTA-treated one, suggesting that both ethanol and nonalcoholic fractions may preserve antioxidant reserve. GSH/GSSG ratio was significantly preserved only in the OTA-wine group and not in OTA-ethanol. Red wine may exert a protective effect against OTA nephrotoxicity by limiting oxidative damage. The ostensible protection afforded by ethanol deserves further investigation.  相似文献   
35.
Epidemiological studies have demonstrated that many antioxidants and the total antioxidant capacity (TAC) of the diet may protect against cancers and cardiovascular disease. Common fruits and vegetables are good sources of antioxidants, although in some Mediterranean areas traditional wild greens are responsible for a significant percentage of total dietary antioxidant intake. In the European Prospective Investigation into Cancer and Nutrition cohort of Ragusa (Sicily), a high number of subjects were found to frequently eat wild greens, including Sinapis incana and Sinapis nigra, Diplotaxis erucoides, Cichorium intybus, Asparagus acutifolius, and Borrago officinalis. On the basis of these observations, detailed characterization of single antioxidant components (i.e., polyphenols, carotenoids, chlorophylls, and ascorbic acid) and the TAC of these edible wild traditional plants was performed. The wild plants examined were found to be very rich in antioxidants, such as flavonoids and carotenoids, with high TAC values, suggesting that the importance of these vegetables, not only in the traditional but even in the contemporary diet, needs to be emphasized.  相似文献   
36.
A possible alternative to minimize the effects of salt and drought stress is the introduction of species tolerating these conditions with a good adaptability in terms of quantitative and qualitative yield. So quinoa (Chenopodium quinoa Willd.) cultivar Titicaca was grown in an open field trial in 2009 and 2010 to investigate the effects of salt and drought stress on quantitative and qualitative aspects of the yield. Treatments irrigated with well water (Q100, Q50 and Q25) and corresponding treatments irrigated with saline water (Q100S, Q50S and Q25S) with an electrical conductivity (ECw) of 22 dS m?1 were compared. Salt and drought stress in both years did not cause significant yield reduction, while the highest level of saline water resulted in higher mean seed weight and as a consequence the increase in fibre and total saponin content in quinoa seeds.  相似文献   
37.
Summary

The effects of different BA and IBA concentrations and dark/light combinations, applied during both the last proliferating subculture (LPS) and the regeneration phase (RP), on shoot regeneration from leaves were evaluated in M.26 apple rootstock. A positive influence on caulogenesis was found with a low cytokinin/auxin ratio in the medium during the LPS. The increase in IBA concentration from 0.49 μM to 4.92 μM in the LPS, along with the absence or the use of a low cytokinin concentration (0.89 μM) in the medium, enhanced the subsequent shoot regeneration from leaves. During the RP, a concentration of 22.2 μM BA gave the best caulogenesis results. During both the LPS and the RP, high IBA concentrations were able to replace the combined effect of a low IBA concentration and dark treatment; this could indicate that dark treatments interact with the auxin metabolism in the leaf caulogenesis response. Auxin application could not reproduce all the effects of dark treatments, suggesting that dark also affects other biochemical and/or physiological aspects, such as gibberellin metabolism. Moreover, cytokinins applied during both the LPS and the RP influenced the size of regenerated shoots.  相似文献   
38.
The Mar Piccolo (surface area of 20.72 km2) is located in the Northern area of the Taranto town (Ionian Sea, Italy). It is an inner, semi-enclosed basin with lagoon features connected with the Mar Grande through two channels which are very important for water exchange. Mar Piccolo basin is subjected to urbanization, industry, agriculture, aquaculture and commercial fishing. Hence, it is important to have a temporal picture both of heavy metal content and of organic carbon and their distribution (hydrophobic fraction, hydrophilic fraction, humic compounds) to check the progress of pollution in time. Three sediment cores collected on the basis of the pollution sources have been analyzed. Both heavy metal and organic carbon concentrations underline the fact that the anthropogenic input is different in the three sites, and that in time the amount of pollutants coming into the Mar Piccolo have changed in different ways. The high amount of organic hydrophilic compounds present in sediments, both due to the small water depth and to the high accumulation rate, make the sediment site high in oxygen consumption due to a considerable chemical and biochemical transformations of organic matter.  相似文献   
39.
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An 8-month-old owned European cat showing abdominal pain, fever, distended painful bladder and urinary blockage was presented. Intravenous fluids were immediately administered and, after sedation, a urinary catheter was applied. Blood and urine analysis revealed cystitis and a moderate-to-severe degree of renal failure. About 20 thread-like nematodes, identified as Capillaria plica larvae and fragments of adult stages, were found in the urine sediment. After treatment with an oral formulation of fenbendazole at 25 mg/kg q 12 h for 10 days, urinary signs and bladder worms disappeared. Cases of Capillaria species bladder worms in cats are rarely reported and most infected cats show no clinical signs, presumably because of a low parasite burden. In the present study, feline capillariosis was associated to urethral obstruction, severe difficulties in urination, cystitis and renal failures.  相似文献   
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