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排序方式: 共有701条查询结果,搜索用时 359 毫秒
101.
José Maria Villela Pádua Kaio Olímpio Das Graças Dias Maria Marta Pastina João Cândido de Souza Valéria Aparecida Vieira Queiroz Rodrigo Veras da Costa Maria Beatriz Pereira da Silva Carlos Alexandre Gomes Ribeiro Claudia Teixeira Guimarães Salvador Alejandro Gezan Lauro José Moreira Guimarães 《Euphytica》2016,211(3):277-285
102.
Isidro A. Prez M. Luisa Snchez M. ngeles García Beatriz de Torre 《Agricultural and Forest Meteorology》2009,149(10):1686-1692
CO2 is one of the most important gases linked to climate change. However, its ambient concentrations in a clean atmosphere have scarcely been investigated. In this paper a close relationship between CO2 concentrations and meteorological variables was proposed to establish atmospheric conditions linked to high CO2 values. A detailed 3-year campaign was carried out in a rural area with a CO2 continuous analyser and a RASS sodar for meteorological variables. Daily and yearly CO2 cycles were obtained. In addition, semi-hourly medians and quartiles were fitted to straight lines during the night time and daily maxima and minima were parameterised by means of a second order cylindrical model. Six meteorological variables were considered: wind speed, wind direction and temperature at one level and differences between them at two levels. Intervals were proposed from the highest CO2 concentrations during the night to build up a binary system of 64 meteorological classes. Analysis of both CO2 medians and meteorological classes enabled simplification of the system to four groups. The first group, characterised by high temperatures and drainage flow, was associated with detrended median concentrations above 15 ppm. Two groups of moderate concentrations were linked to thermal inversions and no prevailing wind directions. The final group corresponded to low concentrations associated with less than three meteorological variables with values linked to high concentrations. Only high directional shear and low wind speed were relevant in this group. This 4-group system was successfully used with the whole dataset. 相似文献
103.
Susana Pedraza-Díaz Luis M. Ortega-Mora Beatriz A. Carrin Vanesa Navarro Mercedes Gmez-Bautista 《Veterinary parasitology》2009,160(3-4):204-210
In this study, we investigated the presence of Cryptosporidium in 171 faecal samples from reptiles commonly used as pet animals. These include lizards belonging to the genera Eublepharis, Pogona, Chlamydosaurus, Hemiteconyx, Teratoscincus, Tiliqua, Iguana, and Chamaeleo, snakes of the genera Lampropeltis, Elaphe, Python, Boa and Corallus, and tortoises belonging to the genera Testudo and Kinixys. Cryptosporidium oocysts were detected by immunofluorescence using a commercially available kit and cryptosporidial DNA by amplification of a polymorphic fragment of the 18S rDNA and the HSP70 locus.Cryptosporidium was detected in 38.6% and 25.1% of the samples analysed by immunofluorescence and PCR, respectively. Molecular characterisation of the isolates confirmed that C. serpentis and C. varanii (syn. C. saurophilum) are the main species involved in infection in pet reptiles but also showed the presence of C. parvum and C. muris, as well as other species or genotypes of this parasite including the Cryptosporidium mouse genotype and Cryptosporidium tortoise genotype previously described in reptiles. In addition, a Cryptosporidium sp. was isolated from a chameleon and a python. 相似文献
104.
Gustavo A. Ramírez Jaume Altimira Beatriz García Marcos Fernández† Miquel Vilafranca 《Veterinary dermatology》2009,20(1):35-41
Straelensiosis is a relatively new disease described in dogs and produced by a trombiculid larva known as Straelensia cynotis . Few cases have been reported in the English literature. Straelensiosis has been observed in Southern France and Northern Portugal causing a distinctive nodular dermatitis. The present study describes the clinical, histopathological and epidemiological features of 19 cases diagnosed as straelensiosis in the north of Spain and Portugal (2003–2007). A follow-up of the animals after diagnosis was carried out. Differences with previously described cases were observed, especially concerning epidemiology and histopathology. The grade of response to different treatments and new microscopic features are discussed. The study concludes that S. cynotis can cause a nodular dermatitis in rural and hunting dogs in Spain and Portugal and is associated with particular seasonal and geographical factors. 相似文献
105.
Alvarez J de Juan L Bezos J Romero B Sáez JL Marqués S Domínguez C Mínguez O Fernández-Mardomingo B Mateos A Domínguez L Aranaz A 《Veterinary microbiology》2009,135(3-4):389-393
Interferon-gamma (IFN-gamma) detection assay is being applied as an ancillary test to tuberculin tests in the diagnosis of bovine tuberculosis to detect the maximum number of infected animals. Among possible factors influencing the performance of tuberculosis-diagnostic tests, paratuberculosis, a widespread disease in Spain and other European countries, has been pointed out as a cause of false positive reactions. Still, its effect on the sensitivity of these tests in cattle has yet to be fully characterized. The impact of paratuberculosis in the apparent sensitivity of IFN-gamma assay was studied in a bullfighting cattle herd with a mixed tuberculosis-paratuberculosis infection, using culture of Mycobacterium bovis and Mycobacterium avium paratuberculosis as the gold standard to determine the infection status of every animal. A total of 218 animals were slaughtered and sampled for bacteriology after blood sampling. IFN-gamma assay showed a lower apparent sensitivity in animals with a mixed infection (50%) compared to all animals suffering tuberculosis (78.3%). This finding indicates that the presence of paratuberculosis in tuberculosis-infected herds could imply a serious impairment in the sensitivity of IFN-gamma detection test. 相似文献
106.
Amaral JS Casal S Seabra RM Oliveira BP 《Journal of agricultural and food chemistry》2006,54(4):1315-1321
The effect of roasting on some nutritional characteristics of hazelnut lipidic fraction was investigated. Hazelnuts (Corylus avellana L.) were submitted to several different thermal treatments, comprising different temperatures (125-200 degrees C) and times of exposure (5, 15, and 30 min) and analyzed for their moisture and crude fat. Raw and roasted hazelnuts were also analyzed for their compositions in phytosterols and fatty acids (including trans isomers) by GC-FID, triacylglycerols by HPLC-ELSD, and tocopherols and tocotrienols by HPLC-DAD/fluorescence spectroscopy. Minor changes occurred in the fatty acid and triacylglycerol compositions. As temperatures and roasting periods increased, generally, a modest increase of oleic and saturated fatty acids and a decrease of linoleic acid, expressed as relative percentages, occurred. Similarly, an increase of triacylglycerols containing oleic acid moieties and a decrease of those containing linoleic acid moieties were found in the roasted samples. Roasting caused a modest decrease of the beneficial phytosterols (maximum 14.4%) and vitamin E homologues (maximum 10.0%) and a negligible increase of the trans fatty acids. 相似文献
107.
Gerhard Langenberger Vanessa Prigge Konrad Martin Beatriz Belonias Joachim Sauerborn 《Agroforestry Systems》2009,76(1):173-194
Complex agroforestry systems that mimic local forest structure, so-called ‘analogs’, are assumed to be of specific value to
rural people as well as the environment. The objective of this study was to document and evaluate the utilization of plant
resources by Philippine lowland farmers to identify native species suitable for integration in such a system. The interviewed
farmers maintain a comprehensive ethnobotanical knowledge. They reported using 122 plant species for 77 purposes. Eighty species
have medicinal value, 35 provide food, and 32 serve other uses. About 64% of the identified species are Philippine natives.
The life form composition of these species is dominated by trees but also includes herbs, lianas, and graminoids, thus providing
the structural elements required in analog systems. Nevertheless, only a few of the species seem to be promising for cultivation.
Many of them are ubiquitous in the vicinity of villages. Some species are also not much appreciated but act as staple food
only during food shortage. Even though several of the species have proven market value, such as rattan (e.g. Calamus
merrillii), or are reputed medicines, such as ‘Philippine ginseng’ (Sarcandra glabra), no cultivation could be observed. This shows that usefulness in itself cannot be the only criterion to promote species
but that it requires a careful analysis of the marketability of the respective species. In this context we suggest the following
three species that are of proven medicinal value for in-depth study: the liana Tinospora crispa (Menispermaceae), the tree Picrasma javanica (Simaroubaceae), and the herb Sarcandra glabra (Chloranthaceae). They represent three different life form strategies and would thus fit well in vertically structured agroforestry
systems. 相似文献
108.
Beatriz Rumeu Manuel Nogales Rui B. Elias David P. Padilla Tiago Resendes Airam Rodríguez Francisco Valdés Eduardo Dias 《European Journal of Forest Research》2009,128(6):567-574
Phenology and female cone characteristics of the two endemic cedars (Juniperus cedrus and J. brevifolia) from the Macaronesian islands were studied. Despite their closely taxonomic affinity and their evolution under insular conditions,
different trends were recorded. Mature J. cedrus female cones were present throughout the year, while those from J. brevifolia were only present in summer and autumn. J. cedrus female cone size was significantly larger than that of J. brevifolia, a trend consistent with the presence of larger vertebrates (lizards and birds) in the Canary Islands. However, water content
was four times higher in J. brevifolia female cones, which can be related with the higher rainfall existing in the Azores. J. cedrus has two or three seeds per cone, whereas J. brevifolia frequently had three. Seeds from J. cedrus were clearly larger and heavier, coinciding with the female cone size trend. However, tetrazolium tests revealed higher viability
values in J. brevifolia. The relatively low percentage of filled seeds in J. cedrus could be a consequence of the climatic stress and limits to pollination due to fragmented populations as described for other
Juniperus species. In summary, our results reveal that some environmental factors such as the harsh conditions, high population fragmentation
and the dependence on large dispersers have compromised the fitness of J. cedrus in the Canary Islands. 相似文献
109.
The potential of the entomopathogenic nematode Steinernema feltiae (Filipjev) (Rhabditida: Steinernematidae) Rioja strain was assessed under laboratory conditions. Last instar larvae of Leptinotarsa decemlineata Say (Coleptera: Chrysomelidae), Spodoptera littoralis Boisdouval (Lepidoptera: Noctuidae) and Trichoplusia ni Hübner (Lepidoptera: Noctuidae) were exposed to infective juveniles (IJs) under laboratory conditions. Larval mortality,
days to larval death, infection cycle length, and reproductive potential were recorded. Efficacy was assessed performing dose–response
experiments. The results indicate that control of L. decemlineata with S. feltiae Rioja strain is not economically profitable (LC50 = 99.61 IJs/cm2), whereas results obtained for T. ni (LC50 = 0.27 IJs/cm2) are promising. Due to the life cycle of this insect, the efficacy needs to be investigated in foliar application studies.
The effects on S. littoralis (LC50 = 0.69 IJs/cm2) was considered the most suitable for development of the Rioja strain as a biocontrol agent for soil application. 相似文献
110.
Rojas-García C García-Lara S Serna-Saldivar SO Gutiérrez-Uribe JA 《Plant foods for human nutrition (Dordrecht, Netherlands)》2012,67(1):94-99
Free and bound phenolics extracts from nejayote solids were obtained after optimally lime-cooking blue, normal white, red,
normal yellow, high-carotenoid and quality protein maize types. The extraction yield ranged from 4.47 to 10.05%. Bound phenolics
extracts had higher content of total phenolics, antioxidant activity and ferulic acid compared to the free phenolics extracts.
In general, free phenolics extracts were less cytotoxic than the bound phenolics counterparts. Bound phenolics extracts had
higher induction of quinone reductase (QR) and particularly the normal yellow nejayote exerted the highest chemopreventive
index tested in Hepa1c1c7 cells. When tested for monofunctional phase 2 induction capacity in BPrc1 cells, the bound phenolics
extracts of blue, normal white and quality protein nejayotes were better inducers than the normal yellow counterpart. Particularly,
the free phenolics extract of the white maize nejayote induced BPrc1 cells QR and exerted a higher chemopreventive index compared
to the bound phenolics extract. Therefore, the nejayote of the normal white maize was the best source of monofunctional phase
2 enzyme inducers. 相似文献