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141.
Paolacci AR Miraldi C Tanzarella OA Badiani M Porceddu E Nali C Lorenzini G Ciaffi M 《Tree physiology》2007,27(11):1541-1550
Seedlings of Phillyrea latifolia L., a Mediterranean shrub, were exposed for 90 days to 110 nl l(-1) ozone (O(3)). Comparison of the cDNA-amplified fragment length polymorphism (cDNA-AFLP) patterns for treated and control plants allowed the identification and cloning of 88 differential sequences induced by O(3). The differential expression of 67 cloned sequences was further confirmed by RT-PCR. The functions of 36 cloned sequences, corresponding to seven of the twelve gene functional classes of Arabidopsis, were presumed on the basis of their homology with characterized gene sequences. Ozone induction of genes homologous to 24 of the clones has been reported in other plant species, whereas the induction of the 12 remaining sequences has not been observed before. Ozone activation of these newly identified genes could be a result of the chronic exposure to low O(3) concentration, because in most previous studies, acute treatments, involving high O(3) dosages, were applied. Possible roles of the cloned sequences in the response of P. latifolia to O(3) and other causes of oxidative stress are discussed. 相似文献
142.
Tobias Schwarz MA Dr. Med. Vet. Federica Morandi DVM Giacomo Gnudi Dr. Med. Vet. Erik Wisner DVM Calum Paterson MSc Martin Sullivan BVMS PhD Pamela Johnston BVM&S PhD 《Veterinary radiology & ultrasound》2000,41(4):335-339
The radiographic appearance of nodular fat necrosis is described in ten cats and one dog. The most common radiographic sign was the presence of a focal mineralized circular to oval soft tissue mass in the abdominal fat as present in 9 cats. These masses had a distinct eggshell-like rim encapsulating the lesion. In one cat and one dog multiple masses were present, without radiographic signs of mineralization. Abdominal ultrasound was performed in three cats and one dog, findings included the presence of hyperechoic masses with associated acoustic shadowing, some with a hypoechoic centre. Almost all animals were old and obese. In three cats and one dog, changes were confirmed with biopsy or post mortem examination. Lesions having the appearance of those in this paper are most likely incidental findings and should not be confused with abdominal masses of neoplastic origin. Ultrasound can be helpful in identifying such lesions. 相似文献
143.
144.
Nardi F Spinsanti G Boore JL Carapelli A Dallai R Frati F 《Science (New York, N.Y.)》2003,299(5614):1887-1889
Recent morphological and molecular evidence has changed interpretations of arthropod phylogeny and evolution. Here we compare complete mitochondrial genomes to show that Collembola, a wingless group traditionally considered as basal to all insects, appears instead to constitute a separate evolutionary lineage that branched much earlier than the separation of many crustaceans and insects and independently adapted to life on land. Therefore, the taxon Hexapoda, as commonly defined to include all six-legged arthropods, is not monophyletic. 相似文献
145.
S. BOGOVSKI L. ROSSI V. BOCCHINI S. LASTRAIOLI C. AIELLO L. SANTI 《Journal of fish diseases》1994,17(6):557-566
Abstract. Twenty malignant lymphomas of northern pike, Esox lucius L., from the Baltic coast of Estonia were investigated immunohistochemically using rabbit anti-human polyclonal antibodies against lysozyme (LYS), alpha-1-antichymotrypsin (ACT) and S-100 protein. Based on the strongly positive reactions to LYS, ACT and S-100 found in a great number of histiocytes, two of these tumours were classified as histocytic diffuse malignant lymphomas. Furthermore, the weaker positive reaction to these antibodies detected in some of the histocytes in 10 other cases of diffuse malignant lymphoma indicates their histocytoid-lymphocytic origin. In addition, the lack of reaction to all antibodies used found in the remaining eight tumours, as well as their general morphological structure, allowed their diagnosis as lymphocytic diffuse malignant lymphomas. Thus, the immunohistochemical reactions to LYS, ACT and S-100 served as a tool for precisely distinguishing between the different types of lymphomas as well as for better understanding their origin. 相似文献
146.
A 3-yr-old male Gouldian finch (Erythrura gouldiae) died after 2 wk of lethargy, emaciation, feather loss, and abdominal distension. The bird was housed in an aviary for breeding, but it had shown loss of fertility in the previous breeding season. Necropsy revealed a gross, firm, and yellow mass involving the left testis. Histologically, the mass was a mixed form, intratubular and diffuse, Sertoli cell tumor. Some neoplastic cells had intranuclear inclusion bodies that immunoelectron microscopy proved to be polyomavirus particle aggregates. There were no viral inclusions in other tissues. The possible role of infection in the pathogenesis of the tumor is discussed. 相似文献
147.
Poplar wood heat treatment: effect of air ventilation rate and initial moisture content on reaction kinetics,physical and mechanical properties 总被引:1,自引:0,他引:1
The kinetics of heat treatment as well as its effect on some physical and mechanical properties of poplar wood (Populus alba L.) were analysed in this research. Kinetic tests were performed at different treatment temperatures and two different air ventilation settings [low and high air exchange rate (AER) with the exterior]. The treatment kinetics was studied, starting from the oven-dry condition, according to the mass loss during time. The time–temperature equivalency was checked, the mass loss versus time formalised through a master curve. The analysis clearly showed how the heat treatment at low and high AER presents different degradation kinetics even if similar activation energy values were found. Some physical and mechanical properties of wood after treatments up to a mass loss of 7 and 10 % starting from oven-dry or standard environmental conditions state were also studied. All of the treated samples showed statistically significant differences compared to the untreated one. The treatments performed at 7 or 10 % of dry mass loss showed homogeneous behaviour. The same tendency was observed for the treatments starting at oven-dry or standard environmental conditions with the exception of Young’s modulus, which resulted in smaller reductions in wet starting condition when compared to dry samples. 相似文献
148.
Elisa Pellegrini Alessandra Campanella Giacomo Lorenzini Cristina Nali 《Urban Forestry & Urban Greening》2014,13(4):800-805
The wide diffusion of tropospheric ozone is a major environmental problem, in urban area as well as in rural and remote localities. Its increasing man-related levels are connected to severe impacts on human life and welfare, in terms of adverse health effects, damage to manufacts and injury to plants. Biological monitoring is a powerful tool for filling the gap between the causes and the effects of environmental toxins, as bioindication agents assess in an easy-to-detect fashion the effects of pollution on (selected) biota. A project was launched in 2012 to involve some 190 students (ages 11–16) from three schools in Central Italy in biodetection of ozone effects with the hypersensitive plant Nicotiana tabacum Bel-W3. The project also involved teachers and families of the pupils. Results implied the reading of 12,000 biological data (ozone injury on cotyledons) and were fortified by data captured by four automatic analyzers (1300 raw data of hourly means). Biological and chemical data compared favorably and were treated with geostatistical methods; results are exposed in the form of cartographic restitutions. Under the guidance of their teachers, the pupils had several opportunities to practice with many basic and applied study areas and disciplines and were initiated into the scientific method in a simple and absorbing manner. Though primarily an educational exercise, the survey provided sound research elements and the picture of pollution that emerged has increased the knowledge of air quality in the area. Biomonitoring is confirmed to be a powerful tool to involve young people in environmental topics. 相似文献
149.
Maria Paola Ferranti Javier Guallart Virginia Cortella Giacomo Terenziani Mariachiara Chiantore 《水产资源保护:海洋与淡水生态系统》2021,31(7):1912-1917
- Effectiveness of restoration/repopulation measures may be strongly hindered by the ability of the target species to cope with the environmental conditions of the receiving area.
- Although a species has been reported previously for a given area, the environmental conditions and human pressures may have changed, potentially making any restoration attempt ineffective. Evidence is provided showing that the endangered ferruginous limpet Patella ferruginea can complete its reproductive cycle in the northernmost sector of the western Mediterranean.
- This supports the idea that the reintroduction and the strict protection of P. ferruginea in the extreme north of its historical geographic range could be effective for the recovery of the species in this area and ultimately the establishment of reproductively viable and stable populations.
- Verification of gonadal maturation of specimens experimentally established on the Gulf of Genoa (Ligurian Sea) coastline, as well as evidence of sex change in one individual (the first outside the Alboran Sea), provides further support of the potential for individuals to complete their reproductive cycle in this area.
- The results support the potential of actions for the restoration of viable populations of the species along the Ligurian coasts through the introduction of juveniles obtained exclusively by aquaculture techniques, in order to mitigate any impact on donor sites.
150.
G. MARINO C. BOGLIONE B. BERTOLINI A. ROSSI F. FERRERI S. CATAUDELLA 《Aquaculture Research》1993,24(3):445-456
Abstract The development of the fin skeleton has been studied in both the wild and hatchery sea bass, Dicentrarchus labrax L., larvae, in order to identify and define morphofunctional criteria for larval quality assessments. The cartilaginous and bony skeletal elements of the larvae were studied and standard length and notochord flexure recorded. Fin anomalies were present in reared larvae, whereas they were rare or absent in specimens from the wild. These anomalies were recognizable from the very beginning of skeletal development, indicating that environmental, genetic and broodstock management factors influence even the very early stages of larval development. 相似文献