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21.
Soil Bioremediation: Combination of Earthworms and Compost for the Ecological Remediation of a Hydrocarbon Polluted Soil 总被引:1,自引:0,他引:1
Brunello Ceccanti Grazia Masciandaro Carlos Garcia Cristina Macci Serena Doni 《Water, air, and soil pollution》2006,171(1-4):383-397
A three-dimensional (3D) off-line chemical transport model (CTM) has been used to study an Arctic ozone minihole event in early December 2002, when the meteorological conditon were severely colder than in recent years. The minimum temperatures were below 188 K on 6 December 2002 and remained below 195 K for the entire month. Such temperatures are low enough for the formation of PSCs (polar stratospheric clouds) which were observed by a visible/near infrared solar occultation instrument by the Polar Ozone and Aerosol Measurement (POAM) III experiment. The SLIMCAT model compares well with the depth and evolution of the ozone distribution as observed by the second European Remote Sensing Satellite (ERS-2) Global Ozone Monitoring Experiment (GOME). The combined effect of a very strong and large intrusion of sub-tropical air, and uplifting of air masses of low ozone concentrations from the troposphere plays important role in the fomation of the ozone minihole. The modelled chemical ozone loss rate was relatively fast in the lower stratosphere in the region of frequent PSCs and higher levels of ClO and BrO. The observed PSCs in the vicinity of the minihole supports the model-predicted location of PSCs and chlorine activation. However, ozone miniholes have been attributed almost entirely to dynamical effects due to its short duration. 相似文献
22.
Iorizzi M Lanzotti V De Marino S Zollo F Blanco-Molina M Macho A Muñoz E 《Journal of agricultural and food chemistry》2001,49(4):2022-2029
Investigation of polar extracts from ripe fruits of Capsicum annuum L. var. acuminatum yielded three new glycosides, capsosides A (1) and B (2) and capsianoside VII (3), along with seven known compounds (4-10). The chemical structures were elucidated mainly by extensive nuclear magnetic resonance methods and mass spectrometry, and the biological activities of icariside E(5) (4) were tested by different assays. Icariside E(5), in contrast to capsaicin, neither induces an increase in the intracellular levels of reactive oxygen species nor affects the mitochondria permeability transition, and it does not signal through the vanilloid receptor type 1. Interestingly, this compound protects Jurkat cells from apoptosis induced by the oxidative stress mediated by serum withdrawal. These results suggest that icariside E(5) may have antioxidant properties that strengthen the importance of peppers in the Mediterranean diet. 相似文献
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Greco G Madio A Buonavoglia D Totaro M Corrente M Martella V Buonavoglia C 《Veterinary journal (London, England : 1997)》2005,170(3):65-350
A study was carried out in the South of Italy to assess the role of clostridia in neonatal diseases of lambs and kids. Eighty-seven lambs and 15 kids belonging to 25 flocks were examined and Clostridium perfringens was the microorganism most commonly identified. C. perfringens isolates were analysed by polymerase chain reaction (PCR), in order to determine the prevalence of the genes cpa, cpb, cpb2, etx, iap and cpe. The most prevalent toxin-type of C. perfringens was found to be type A found in 84% of the cases with clostridial enterotoxaemia. No C. perfringens type B, C or E were found. C. perfringens type D was isolated in 16% of the cases. About 24% of the isolates were cpb2 positive. The prevalence of cpb2 across the different C. perfringens types varied. The beta(2)-toxin gene cpb2 was detected in 4/21 (19%) type A isolates, in 1/2 type D isolates, and in 1/2 type DE (cpe-carrying type D) isolates. The high rate of positivity to cpb2 among the isolates suggests that a vaccine based on the beta(2)-toxin, should be included in the vaccination schedule of the animals to confer adequate protection and to prevent the disease. 相似文献
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One hundred years ago a small group of psychiatrists described the abnormal protein deposits in the brain that define the most common neurodegenerative diseases. Over the past 25 years, it has become clear that the proteins forming the deposits are central to the disease process. Amyloid-beta and tau make up the plaques and tangles of Alzheimer's disease, where these normally soluble proteins assemble into amyloid-like filaments. Tau inclusions are also found in a number of related disorders. Genetic studies have shown that dysfunction of amyloid-beta or tau is sufficient to cause dementia. The ongoing molecular dissection of the neurodegenerative pathways is expected to lead to a true understanding of disease pathogenesis. 相似文献
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Introduction : Canine transmissible venereal tumour is occasionally observed in leishmaniotic dogs, and Leishmania amastigotes can be harboured in canine transmissible venereal tumour cells. Objectives : The aim of this paper was to investigate the clinicopathological significance of the association of both diseases. Methods : Nineteen dogs affected by canine transmissible venereal tumour and canine leishmaniasis were studied retrospectively. Results : In these dogs, the tumour manifested a large size and often aggressive behaviour (42%) and no predictive sign of spontaneous regression was observed. Sporadic Leishmania amastigotes were found within the canine transmissible venereal tumour in three cases, probably transported by infected macrophages often infiltrating the tumour. A high Leishmania parasitisation of canine transmissible venereal tumour was observed in two other cases and verified by immunohistochemistry. Clinical Significance : Canine transmissible venereal tumour is a tumour of the dog able to harbour a large number of Leishmania parasites. Alternatively, the systemic disease (canine leishmaniasis) may lower the immune defence against malignancy (canine transmissible venereal tumour). 相似文献
29.
Marco Quartuccio Gabriele Marino Giuseppe Garufi Santo Cristarella Antonina Zangh�� 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(2):207-209
The association of cryptorchidism, functional Sertoli cell tumors, and spermatic cord torsion has been rarely reported in the literature. Two dogs were admitted for bilateral skin alopecia and weight loss. Both animals were cryptorchid and displayed a pendulous preputial sheath, prostate hypertrophy, and increased levels of circulating oestrogen. Transabdominal palpation and ultrasonography revealed the presence of neoplastic retained gonads. During surgery, spermatic cord torsion was also detected in the enlarged neoplastic testes of both dogs. Histologic examination confirmed the presence of Sertoli cell tumors that were primarily responsible for the feminizing syndrome. Complete remission of all symptoms occurred within 3 months after orchiectomy. 相似文献
30.
Factors affecting the infiltration capacity in bamboo groves 总被引:1,自引:0,他引:1
To determine the effects of the characteristics of litter and surface soil on the infiltration capacity in bamboo groves, infiltration rates were measured on a plot-scale using an oscillating-nozzle rainfall simulator at seven Moso bamboo (Phyllostachys pubescens) sites and one Madake (P. bambusoides) site in Japan. The maximum final infiltration rate (FIRmax), which was defined in this study as the infiltration capacity, was calculated, and the correlation between FIRmax and earth surface properties was analyzed. The FIRmax ranged from 9 to 308?mm?h?1, showing little correlation with litter as surface cover, and a weak correlation with bulk density (0.3–0.9?g?cm?3) and organic matter content (10.4–45.9%). These results suggest that the bulk density and organic matter content of surface soil, rather than surface cover, can be the controlling factors of infiltration capacity in bamboo groves. The bulk density of surface soil correlated significantly with the soil organic matter content, represented by bamboo rhizomes, suggesting that the infiltration capacity can increase with the amount of root networks present, related to macropore formation. The stand density showed a weak positive correlation, although not significant, with the soil organic matter content and a positive correlation with FIRmax. Thus, the infiltration capacity of bamboo groves can increase as the stand density of culms and bamboo rhizomes increase. 相似文献