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The effect of two nonsteroidal anti-inflammatory drugs (carprofen and ketoprofen) on platelet adhesion and aggregation functions was evaluated by the PFA-100 analyser (Dade-Behring, CA, U.S.A.) using its collagen-adenosine diphosphate (ADP) and collagen-epinephrine (EPI) cartridges. The function of platelets was evaluated in 55 healthy dogs, in 7 dogs treated with ketoprofen and in 31 dogs treated with carprofen in a therapeutic dose for minimum 5 days. The therapeutic doses of carprofen had no effect on the closure time of PFA-100 (which is the marker of platelet function) but ketoprofen caused a significant increase when using collagen-EPI stimulation The closure times for both the healthy (control) and the treated dogs using EPI cartridges were often longer than the upper default cut-off point (300 sec) of the device. The PFA-100 analyser with collagen-ADP cartridges could be a useful tool for veterinary applications including the evaluation of platelet aggregation in dogs treated with NSAIDs. The upper cut-off point of PFA-100 might be extended. 相似文献
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Haematological and biochemical profiles of carp blood following nitrite exposure at different concentrations of chloride 总被引:1,自引:0,他引:1
Zdeka Svobodová Jana Máchová Jana Drastichová Ladislav Groch Vra Lusková Gorzyslaw Poleszczuk Josef Velíek & Hana Kroupová 《Aquaculture Research》2005,36(12):1177-1184
Haematological parameters of 2‐year‐old carp (Cyprinus carpio L.) were assessed to study the protective effect of chloride on the health of fish exposed to elevated nitrite concentrations. Four groups of carp were exposed to different concentrations of nitrite and chloride for 96 h (group E1: 67 mg L?1 NO2?, 11 mg L?1 Cl?; group E2: 67 mg L?1 NO2?, 100 mg L?1 Cl?; group E3: 0 mg L?1 O2?, 100 mg L?1 Cl? and group C: 0 mg L?1 NO2?, 11 mg L?1 Cl?). The main haematological response of carp to an acute exposure to nitrite (group E1) was a significant decrease (P<0.05) in haemoglobin concentrations (53.40±6.61 g L?1), haematocrit (0.21±0.02 LL?1), erythrocyte count (1.13±0.12 TL?1), leucocyte count (7.1±4.19 GL?1) and lymphocyte count (5.28±2.51 GL?1), and a significant increase in methaemoglobin concentration (90.50±4.38%, P<0.01) and mean corpuscular haemoglobin concentration (0.27±0.2 LL?1, P<0.05). At higher chloride concentrations (group E2), a lower nitrite toxicity was observed. In group E2 carp, methaemoglobin made up 38.32±13.30%. Erythrocytes in carp exposed to nitrite showed qualitative changes. Compared with the control group C, group E1 carp showed a significantly higher number (P<0.05) of elongated erythrocytes, with the nucleus located at one cell pole (0.519±0.388 TL?1). All erythrocytes of group E1 carp had remarkably clear cytoplasms compared with the cytoplasm in the control group C. The biochemical values found were comparable with those found in controls. The main histological lesions were found in the gills of carp exposed to nitrite and consisted of hyperplasia and an elevated number of chloride cells. 相似文献
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Jochen Schöngart Florian Wittmann Angélica Faria de Resende Cyro Assahira Guilherme de Sousa Lobo Juliana Rocha Duarte Neves Maíra da Rocha Gisele Biem Mori Adriano Costa Quaresma Layon Oreste Demarchi Bianca Weiss Albuquerque Yuri Oliveira Feitosa Gilvan da Silva Costa Gildo Vieira Feitoza Flávia Machado Durgante Aline Lopes Susan E. Trumbore Thiago Sanna Freire Silva Hans ter Steege Adalberto Luis Val Wolfgang J. Junk Maria Teresa Fernandez Piedade 《水产资源保护:海洋与淡水生态系统》2021,31(12):1117-1135
- The Balbina hydropower dam in the Central Amazon basin, established in the Uatumã River in the 1980s, is emblematic for its socio-environmental disaster. Its environmental impacts go far beyond the reservoir and dam, however, affecting the floodplain forests (igapó) in the downstream area (dam shadow), which have been assessed using a transdisciplinary research approach, synthesized in this review.
- Floodplain tree species are adapted to a regular and predictable flood pulse, with high- and low-water periods occurring during the year. This was severely affected by the operation of the Balbina dam, which caused the suppression of both the aquatic phase at higher floodplain elevations and the terrestrial phase at lower floodplain elevations (termed the ‘sandwich effect’).
- During the period of construction and reservoir fill, large-scale mortality already occurred in the floodplains of the dam shadow as a result of reduced stream flow, in synergy with severe drought conditions induced by El Niño events, causing hydraulic failure and making floodplains vulnerable to wildfires.
- During the operational period of the dam, permanent flooding conditions at low topographical elevations resulted in massive tree mortality. So far, 12% of the igapó forests have died along a downstream river stretch of more than 125 km. As a result of flood suppression at the highest elevations, an encroachment of secondary tree species from upland (terra firme) forests occurred.
- More than 35 years after the implementation of the Balbina dam, the downstream impacts caused massive losses of macrohabitats, ecosystem services, and diversity of flood-adapted tree species, probably cascading down to the entire food web, which must be considered in conservation management.
- These findings are discussed critically, emphasizing the urgent need for the Brazilian environmental regulatory agencies to incorporate downstream impacts in the environmental assessments of several dam projects planned for the Amazon region.
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The authors describe a solitary adenoma in a 5.5-year-old female Budgerigar (Melopsittacus undulatus). The tumour was partially blocking the lumen of the proventriculus and filled it almost completely. Decreased passage of food towards the gizzard and the intestines developed in the bird as result of the obstruction, which periodically hindered the passage, leading to slow emaciation. An epithelial tumour composed of irregular glandular acini was diagnosed by histological examination. Immunohistochemical reaction with pancytokeratin showed a positive cytoplasmic reaction both in the neoplastic and the normal glandular structures. 相似文献
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Shirley Andrea Florez-Rodriguez Rubens Paes de Arruda Maíra Bianchi Rodrigues Alves Fernanda Jordão Affonso Henrique Fulaneti Carvalho Kleber Menegon Lemes Renata Lançoni André Furugen Cesar de Andrade Eneiva Carla Carvalho Celeghini 《Journal of Equine Veterinary Science》2014
The aim of this study was to assess extenders for cooling equine semen at 5°C and to be used in assisted reproductive technologies (ARTs). Four ejaculates were obtained from each of four stallions. Gel-free semen was diluted in three different extenders: (1) SMK, an opaque skim milk–based extender; (2) SMT, a skim milk (65%) and Tyrode medium (35%); and (3) BSAG, a clear extender containing 1% bovine serum albumin. Samples were packaged (10 mL; 50 × 106 sperm/mL) and stored in a cooling device at 5°C for 12 hours. Analyses were done at 0, 4, 8, and 12 hours after cooling. Semen was analyzed for sperm motility characteristics using a computer-assisted sperm analysis, for plasma membrane and acrosome integrity and mitochondrial membrane potential, using fluorescent probes (propidium iodide, Hoechst 33342, fluorescein isothiocyanate–conjugated Pisum sativum agglutinin, and 5,5′,6,6′-tetrachloro-1,1′,3,3′-tetraethylbenzimidazolyl carbocyanine iodide [JC-1]). Morphology was evaluated with differential interference contrast microscopy and sperm chromatin integrity by the toluidine blue technique. Data were analyzed by analysis of variance and by Tukey test, with time as a repeated measure (SAS, 1998), when P < .05 was significant. In general, milk-based extenders (SMT and SMK) showed improved maintenance of semen quality compared with BSAG. Finally, the addition of skim milk to equine semen extender for cooling at 5°C for 12 hours seems to play a crucial role in sperm preservation. Although, optically clearer extenders are desired for use in ARTs, such as sperm sexing, the milk-free extender (BSAG) is less efficient for cooled-stored equine semen. 相似文献
90.
Lukáŝ Veteŝník Ivo Papouŝek Karel Halačka Věra Lusková Jan Mendel 《Fisheries Science》2007,73(4):817-822
A Carassius auratus complex from an artificial wetland in the Morava River basin is composed of triploid females. Based on body depth, sampled
females could be divided into two groups: (i) high-dorsal (42.5% of standard length); and (ii) low-dorsal (36.1% of standard
length). Both groups differed also in number of gill rakers (50.2 versus 45.4, respectively). In concordance with morphological differences, genetic analysis proved the existence of two haplotypes
in examined individuals. The first haplotype is bound to the high-dorsal form with higher number of gill rakers. This is the
most frequent haplotype in populations of the C. a gibelio form in the Czech Republic. The second haplotype is characteristic of the low-dorsal form with a lower number of gill rakers.
This haplotype is close to haplotypes described in the C. a. langsdorfii form, which is known from Japan. and its occurrence within haplotypes specified in European territory is sporadic. 相似文献