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排序方式: 共有481条查询结果,搜索用时 15 毫秒
1.
Georgea Bignardi Jarretta Pedro Primo Bombonato Marcelo Alcindo de Barros Vaz Guimar?es 《Journal of zoo and wildlife medicine》2004,35(3):356-360
Ultrasonography is currently used in veterinary medicine to examine the anatomy and physiology of internal organs and to establish normal standards for exotic animal species. Specifically, the kidneys may be evaluated and measured in length, width, and height. The kidneys in 33 oncilla (Leopardus tigrinus), including 20 males and 13 females, were opportunistically located, characterized, and measured by ultrasound using a 7.5-MHz linear transducer at two different zoologic facilities in S?o Paulo, Brazil. Renal volume was calculated from these linear measurements. The mean linear measurements and volume of the right and left kidneys were not significantly different. 相似文献
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Martia Ferreira Ana Maseda Jaime Fbregas Ana Otero 《Aquaculture (Amsterdam, Netherlands)》2008,279(1-4):126-130
The effect of semi-continuous culture on the nutritional value of microalgae was tested in the rotifer Brachionus plicatilis in short-term enrichment experiments. Isochrysis aff. galbana clone T-ISO was cultured semi-continuously with renewal rates from 10 to 50% of the volume of the culture per day and used to feed the rotifers. After 24 h, dramatic differences in dry weight and protein, lipid and carbohydrate contents were observed in the rotifers depending on the renewal rate applied to the microalgal culture. Rotifers fed T-ISO cultured with low renewal rates showed low dry weight and organic content, whereas rotifers fed microalgae from nutrient-sufficient, high renewal rate cultures showed higher dry weight and increases up to 60% in protein, 35% in lipid and 100% in carbohydrate contents. Feed conversion rate (FCR) and organic FCR decreased with increasing renewal rates, indicating a more efficient assimilation of the microalgal biomass obtained at high growth rates. The fatty acid profile of rotifers reflected that of T-ISO, with maximum content of polyunsaturated fatty acids (PUFAs), n-3 fatty acids and docosahexaenoic acid (DHA) being found in the rotifers fed microalgae from the renewal rate of 40%. Results demonstrate that the biochemical composition of B. plicatilis is strongly modified through the use of semi-continuous cultures of microalgae in short-term enrichment processes. This technique provides an excellent tool to improve the nutritional value of the live feed used in fish larvae cultures. 相似文献
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The politics of water democracy: insights from grassroot struggles in the Ecuadorian Highlands 下载免费PDF全文
Jaime Hoogesteger 《Asia Pacific viewpoint》2017,58(1):74-85
In the past two decades spaces for user participation have been opened within water governance structures at many scales. In this contribution, based on a case study of the Provincial Water Users Federation Interjuntas‐Chimborazo in the Ecuadorian Highlands, I explore how and why formal participation of water users in itself is problematic in terms of democracy. The case shows that for organised peasant water users to work on more democratic water governance, the creation of upscaled federations, alliances, networks and sometimes street protests is crucial to open up spaces in which their interests are represented. This suggests that democracy is not merely about participation, but more importantly, it is about the politics of how democracy is made through conflicts, protests, negotiations and the creation of strategic alliances that challenge the structures and processes through which decisions are taken. 相似文献
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New Forests - Mediterranean holm oak forests are subjected to chronic seasonal droughts coinciding with the warmest conditions during the summer. Importantly, climate change projections support... 相似文献
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Jaime Aguayo Cline Fourrier‐Jeandel Xavier Capdevielle Fabrice Vtillard Dominique Piou Eugenia Iturritxa Ccile Robin 《Forest Pathology》2020,50(1)
Fusarium circinatum is the causal agent of pitch canker, a destructive disease that threatens natural and planted pine forests around the world. Although pitch canker has caused problems in Spain and Portugal, concerning Europe as a whole, the fungus is not established across the pine distribution area. Its dispersion by wind and/or insect vectors could nevertheless play a role in the colonization of currently uninfected stands. It is therefore crucial to develop monitoring tools for its detection. To this end, we assessed the molecular detection of the pathogen in environmental samples of bark beetles and passive spore traps, collected in two infected Pinus radiata plantations in Basque country, Spain. The spread pattern of F. circinatum was assessed by an experimental design that included insect and spore traps installed at the centre, at the edge and outside the plots. Our results showed that F. circinatum was detected in both types of samples, at almost all collection dates. In both type of samples, positive detections were mainly found at the centre of the plots, a lower proportion at the edge, and very few outside. This suggests that long‐distance dispersion of Fusarium circinatum does not rely on wind spore dispersal neither on insect flight. Our study also shows that molecular methods are a powerful tool to monitor the pathogen in environmental samples. 相似文献
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Vernica da Silva Oliveira Meringela Miranda da Cruz Gabriela Suassuna Bezerra Natan Emanuell Sobral e Silva Fernando Henrique Andrade Nogueira Guilherme Maranho Chaves Jos Lamartine Soares Sobrinho Francisco Jaime Bezerra Mendona-Junior Bolívar Ponciano Goulart de Lima Damasceno Attilio Converti dley Antonini Neves de Lima 《Marine drugs》2022,20(2)
In this study, films of chitosan and 2-amino-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile (6CN), a 2-aminothiophene derivative with great pharmacological potential, were prepared as a system for a topical formulation. 6CN-chitosan films were characterized by physicochemical analyses, such as Fourier-transform infrared spectroscopy (FTIR), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electronic microscopy (SEM). Additionally, the antifungal potential of the films was evaluated in vitro against three species of Candida (C. albicans, C. tropicalis, and C. parapsilosis). The results of the FTIR and thermal analysis showed the incorporation of 6CN in the polymer matrix. In the diffractogram, the 6CN-chitosan films exhibited diffraction halos that were characteristic of amorphous structures, while the micrographs showed that 6CN particles were dispersed in the chitosan matrix, exhibiting pores and cracks on the film surface. In addition, the results of antifungal investigation demonstrated that 6CN-chitosan films were effective against Candida species showing potential for application as a new antifungal drug. 相似文献
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Karina Janice Guadalupe Díaz-Resendiz Carlos Eduardo Covantes-Rosales Alma Betsaida Benítez-Trinidad Migdalia Sarahy Navidad-Murrieta Francisco Fabian Razura-Carmona Christian Daniel Carrillo-Cruz Edwin Jaime Frias-Delgadillo Daniela Alejandra Prez-Díaz Matxil Violeta Díaz-Benavides Mercedes Zambrano-Soria Guadalupe Herminia Ventura-Ramn Aurelio Romero-Castro David Alam-Escamilla Manuel Ivn Girn-Prez 《Marine drugs》2022,20(2)
Fucoidan is a polysaccharide obtained from marine brown algae, with anti-inflammatory, anti-viral, and immune-enhancing properties, thus, fucoidan may be used as an alternative treatment (complementary to prescribed medical therapy) for COVID-19 recovery. This work aimed to determine the ex-vivo effects of treatment with fucoidan (20 µg/mL) on mitochondrial membrane potential (ΔΨm, using a cationic cyanine dye, 3,3′-dihexyloxacarbocyanine iodide (DiOC6(3)) on human peripheral blood mononuclear cells (HPBMC) isolated from healthy control (HC) subjects, COVID-19 patients (C-19), and subjects that recently recovered from COVID-19 (R1, 40 ± 13 days after infection). In addition, ex-vivo treatment with fucoidan (20 and 50 µg/mL) was evaluated on ΔΨm loss induced by carbonyl cyanide 3-chlorophenylhydrazone (CCCP, 150 µM) in HPBMC isolated from healthy subjects (H) and recovered subjects at 11 months post-COVID-19 (R2, 335 ± 20 days after infection). Data indicate that SARS-CoV-2 infection induces HPBMC loss of ΔΨm, even 11 months after infection, however, fucoidan promotes recovery of ΔΨm in PBMCs from COVID-19 recovered subjects. Therefore, fucoidan may be a potential treatment to diminish long-term sequelae from COVID-19, using mitochondria as a therapeutic target for the recovery of cellular homeostasis. 相似文献