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91.
92.
Sara Galac Jenny J.C.W.M. Buijtels Jan A. Mol Hans S. Kooistra 《Veterinary journal (London, England : 1997)》2010,183(1):75-80
The medical records of 63 dogs with pituitary-dependent hypercortisolism (PDH) before and during treatment with trilostane were reviewed retrospectively. The correct trilostane dosage in dogs with PDH was based on the resolution of clinical signs and the results of an adrenocorticotropic hormone (ACTH) stimulation test. The mean (±SD) dose rate of trilostane to achieve good clinical control was 2.8 ± 1.0 mg/kg bodyweight. Trilostane treatment resulted in a significant decline in basal plasma cortisol concentrations. The median plasma ACTH concentration (39 pmol/L, range 7–132 pmol/L; n = 60) at the optimal trilostane dosage time was significantly higher (P < 0.001) than before treatment (13 pmol/L, range 2–102 pmol/L). These values did not overlap with plasma ACTH concentrations (range 212–307 pmol/L) of five PDH dogs with trilostane-induced hypocortisolism.The median cortisol/ACTH ratio in well-controlled dogs (0.23, range 0.03–2.5; n = 46) was significantly lower (P < 0.001) than before treatment (2.59, range 0.27–13.25). Trilostane treatment resulted in an insignificant decrease in plasma aldosterone concentration (PAC), but the median plasma renin activity (PRA) at the time the trilostane dosage was considered optimal (265 fmol/L/s, range 70–3280 fmol/L/s; n = 18) was significantly higher (P < 0.001) than prior to treatment (115 fmol/L/s, range 15–1330 fmol/L/s). Similarly, the median PAC/PRA ratio during trilostane treatment (0.16, range 0.003–0.92; n = 17) was significantly lower (P < 0.001) than before treatment (median 0.44, range 0.04–1.33). Trilostane affected both the hypothalamic-pituitary-adrenocortical and the renin–aldosterone axes. The results also suggested that basal plasma ACTH concentration may be used to detect trilostane overdosage. 相似文献
93.
The influence of field shape, area and surrounding landscape on plant species richness in grazed ex-fields 总被引:1,自引:0,他引:1
Over the past 100 years species-rich semi-natural grasslands have decreased dramatically in Western Europe, where former arable fields (ex-fields) are used instead as pasture. The disappearance of semi-natural grasslands has caused a threat to the biodiversity in agricultural landscapes. Many typical grassland plants are dispersal limited, thus grazed ex-fields can be used to investigate if species spontaneously colonise these new grassland habitats. We examined the relationship between surrounding landscape, field area, shape, distance between edge and centre, and plant species diversity in ex-fields that had been grazed for 15-18 years. The results showed that there were 35% more plant species in fields surrounded by commercial forestry production compared to those surrounded by open agricultural landscape. Area and shape did not influence species richness, although there was increasing number of species in the centre with decreasing distance from the edge. Twenty-five percent of the species where typical grassland species, and ex-fields surrounded by forest had 91% more grassland species compared to those in the open landscape. It is possible to increase grassland plant occurrences by grazing ex-fields surrounded by forest or other grassland remnant habitats, particularly in landscapes where grazed semi-natural grasslands are scarce. 相似文献
94.
Sara Brusconi Silvia Bertocchi Barbara Renai Massimiliano Scalici Catherine Souty‐Grosset Francesca Gherardi 《水产资源保护:海洋与淡水生态系统》2008,18(7):1227-1239
- 1. As part of the Austropotamobius pallipes species complex, the crayfish Austropotamobius italicus is a species of community interest whose preservation requires the designation of Special Areas of Conservation (SACs) (Annex II, EU Habitats Directive). This study aimed at (1) assessing the conservation status of this threatened indigenous species by stock assessment in central Italy and (2) identifying some aspects of its elective habitat.
- 2. Surveys were conducted in nine streams harbouring A. italicus (streams WI) and in 10 streams where crayfish populations became extinct at least 5 years before the study (streams WO).
- 3. The results confirmed that A. italicus is a K‐selected species, with a relatively slow growth rate (males: 0.34; females: 0.37) and a long life expectancy (males: 8.2 years; females: 7.8 years). The extant populations are healthy, showing balanced sex‐ratios and well structured age‐class compositions. Mortality is mainly due to fishing, which is illegal in Tuscany.
- 4. Principal Components Analyses showed that the streams WI and WO differ in the abundance of allochthonous plant detritus but not in the taxonomic composition of their macroinvertebrate communities. Age classes were found to be spatially segregated, juveniles mainly using cobbles as substrates and adults seemingly avoiding them.
- 5. The loss of the pristine riverine landscape seems to have been responsible, together with illegal fishing, for the local extinction of the species. As a consequence, retaining, enhancing, and restoring the habitat and its complexity are required for the preservation of A. italicus.
- 6. The designation of SACs might help in this endeavour if accompanied by programmes aimed at publicizing the need for conservation of this species. Unfortunately, crayfish‐focused projects supported by LIFE in Italy since 1992 (4%) and the SACs involved (1.4%) have been relatively few, despite the poor conservation status of this species and its well recognized ecological role.
95.
96.
Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study 下载免费PDF全文
Angela Boggero Alberto Basset Martina Austoni Enrico Barbone Luca Bartolozzi Isabella Bertani Alessandro Campanaro Antonella Cattaneo Fabio Cianferoni Giuseppe Corriero Ambrosius Martin Dörr A. Concetta Elia Gentile Francesco Ficetola Lyudmila Kamburska Gianandrea La Porta Sara Lauceri Alessandro Ludovisi Elda Gaino Enzo Goretti Massimo Lorenzoni Marina Manca Aldo Marchetto Giuseppe Morabito Francesco Nonnis Marzano Alessandro Oggioni Cataldo Pierri Nicoletta Riccardi Giampaolo Rossetti Nicola Ungaro Pietro Volta Silvia Zaupa Diego Fontaneto 《水产资源保护:海洋与淡水生态系统》2014,24(6):841-852
- 相似文献
97.
Zhongqi Cheng Leda Lee Sara Dayan Michael Grinshtein Richard Shaw 《Journal of Soils and Sediments》2011,11(4):628-638
Purpose
Gardening (especially food growing) in urban areas is becoming popular, but urban soils are often very contaminated for historical reasons. There is lack of sufficient information as to the bioavailability of soil heavy metals to plants and human in urban environments. This study examines the relative leachability of Cr, Ni, As, Cd, Zn, and Pb for soils with varying characteristics. The speciation and mobility of these metals can be qualitatively inferred from the leaching experiments. The goal is to use the data to shed some light on their bioavailability to plant and human, as well as the basis for soil remediation. 相似文献98.
Sara E Childs-Sanford Rachel M Peters James K Morrisey Ana Alcaraz 《Journal of zoo and wildlife medicine》2005,36(2):308-312
An adult, female binturong (Arctictis binturong) was examined due to lethargy, inappetence, and an abdominal mass. Diagnostic investigations, including radiographs, abdominal ultrasound, clinical laboratory findings, and a fine-needle aspirate of the mass, were suggestive of a sarcoma with metastasis. Necropsy and histopathologic findings confirmed a widely disseminated sarcomatoid variant of a renal cell carcinoma, likely originating in the left kidney, with metastasis to the right kidney, spleen, pancreas, liver, mesenteric lymph nodes, and lungs. This is the first report of this neoplasm in a binturong and only the second report in the veterinary literature. Sarcomatoid renal cell carcinoma is a rare histologic variant of renal cell carcinoma that is aggressive, commonly metastatic, and associated with a very poor prognosis in humans. Accurate antemortem diagnosis of this tumor may be complicated by its biphasic morphology, which may resemble carcinoma or sarcoma (or both), often necessitating the use of immunohistochemical techniques. 相似文献
99.
Phytoparasitica - The effect of BAY SIR 8514, diflubenzuron and Hercules 24108 on larval growth, pupation and emergence ofTribolium confusum was determined. BAY SIR 8514 was about twice as active... 相似文献