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151.
Knell SC Andreoni AA Dennler M Venzin CM 《Journal of Feline Medicine and Surgery》2010,12(11):874-877
BACKGROUND: Mesenteric volvulus describes a torsion of the small intestine around the mesenteric root, which can be partial or complete. In dogs, it is an uncommon condition, with German shepherd dogs showing a predisposition. Chronic mesenteric volvulus has also been described. In cats, previous reports have documented two cases of small intestinal volvulus, both diagnosed at necropsy, and a further case of volvulus of the colon in a patient that died after surgery. CLINICAL SIGNIFICANCE: This report describes two cats with mesenteric volvulus that were successfully treated. To the authors' knowledge, no reports of antemortem diagnosis or treatment of small intestinal volvulus in cats have previously been published. On the basis of the cases presented, it appears that the diagnosis of intestinal volvulus may be more difficult in cats than in dogs, but that the prognosis may not be as poor. Therefore, it is suggested that owners be encouraged to pursue surgery. 相似文献
152.
G. Basilone A. Bonanno B. Patti S. Mazzola M. Barra A. Cuttitta R. McBride 《Fisheries Oceanography》2013,22(4):309-323
European anchovy egg occurrence and density data from summer surveys (1998–2007) and oceanographic data were examined to study the mechanisms that control the spatial distribution of anchovy spawning habitat in the Strait of Sicily. Quotient analysis indicated habitat preference for temperature (18–19°C), bottom depth (50–100 m), water column stability (13–14 cycle h?1), fluorescence (0.10–0.15 μg m?3 Chl a), salinity (37.5–37.6 PSU), current speed (0.20–0.25 m s?1) and density (26.7–26.8 kg m?3, σt). Canonical discriminant analysis identified temperature, column stability and fluorescence as major drivers of anchovy spawning habitat. Three of the 4 years which had lower egg abundance were warmer years, with low values of primary productivity. A geostrophic current flowing through the Strait (the Atlantic Ionic Stream, AIS) was confirmed as the main source of environmental variability in structuring the anchovy spawning ground by its influence on both the oceanography and distribution of anchovy eggs. This 10‐yr data series demonstrates recurrent but also variable patterns of oceanographic flows and egg distribution. A lack of freshwater flow in this area appears to depress productivity in the region, but certain and variable combinations of environmental conditions can elevate production in some sub‐areas in most years or other sub‐areas in fewer years. These temporal and spatial patterns are consistent with an ocean triad theory postulating that processes of oceanographic enrichment, concentration, and retention may help predict fishery yields. 相似文献
153.
Daniela Minerdi Marino Moretti Yuan Li Laura Gaggero Angelo Garibaldi Maria Lodovica Gullino 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(2):227-237
A conventional PCR and a SYBR Green real-time PCR assays for the detection and quantification of Phytophthora cryptogea, an economically important pathogen, have been developed and tested. A conventional primer set (Cryp1 and Cryp2) was designed
from the Ypt1 gene of P. cryptogea. A 369 bp product was amplified on DNA from 17 isolates of P. cryptogea. No product was amplified on DNA from 34 other Phytophthora spp., water moulds, true fungi and bacteria. In addition, Cryp1/Cryp2 primers were successfully adapted to real-time PCR.
The conventional PCR and real-time PCR assays were compared. The PCR was able to detect the pathogen on naturally infected
gerbera plants and on symptomatic artificially infected plants collected 21 days after pathogen inoculation. The detection
limit was 5 × 103
P. cryptogea zoospores and 16 fg of DNA. Real-time PCR showed a detection limit 100 times lower (50 zoospores, 160 ag of DNA) and the
possibility of detecting the pathogen in symptomless artificially infected plants and in the re-circulating nutrient solution
of closed soilless cultivation systems. 相似文献
154.
155.
Large reservoirs as ecological barriers to downstream movements of Neotropical migratory fish
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Most large rivers in South America are fragmented by large dams, and a common management strategy to mitigate impacts has been construction of fish passes. Recent studies, however, indicate that downstream passage of adults and young fish is nil or minimal. Better understanding of this phenomenon is needed if fishways are to provide any tangible conservation value in South America. We propose, in this article, that large reservoirs impose a different kind of barrier to migrating fish: impoundments create a diffuse gradient of hydraulic/limnological conditions that affects fish behaviour and functions as an extensive environmental filter that discourages downstream movements. To develop this idea, we characterize the barriers created by dams and reservoirs by describing their distinct nature, the effects on fish migration and potential solutions. We show, for example, that dams generally prevent upstream movements, whereas reservoirs impede mainly downstream movements. In this context, we explain how fish passes, in some instances, can partially mitigate fragmentation caused by dams, but there is no technical solution to solve the barrier effect of reservoirs. In addition, we present a body of empirical evidence that supports the theory that large reservoirs are important barriers to fish migration in South America, we offer an overview of the size of reservoirs to show that impoundments typically have large dimensions, and we discuss the significance of this theory for other regions. Based on current and proposed river regulation scenarios, we conclude that conservation of Neotropical migratory fish will be much more complicated than previously believed. 相似文献
156.
157.
Larval population structure of Engraulis encrasicolus in the Strait of Sicily as revealed by morphometric and genetic analysis
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Angela Cuttitta Bernardo Patti Teresa Maggio Enza Maria Quinci Anna Maria Pappalardo Venera Ferrito Vito De Pinto Marco Torri Francesca Falco Aldo Nicosia Marianna Musco Grazia Maria Armeri Francesco Placenti Giorgio Tranchida Roberta Mifsud Angelo Bonanno Salvatore Mazzola 《Fisheries Oceanography》2015,24(2):135-149
In order to investigate the larval population structure, specimens of Engraulis encrasicolus larvae from five different locations in the Strait of Sicily were analyzed by means of otolith readings, morphometric and genetic techniques. The distribution of age in day, identified by means of the otolith readings and associated with the oceanographic parameters, was useful to identify possible spawning areas and transport dynamics. The presence of more than one spawning area suggested the possibility that two or more sub‐populations may co‐exist in the study area. The morphometric characteristics were more adequate than genetic parameters to discriminate the different larval groups. The most relevant variables for the separation were the mouth length (ML) and the body diameter (BD). The population structure by means of genetic data reported the presence of two phylogroups co‐occurring among samples in each sampling locations specimens. The pattern of genetic divergence among anchovy larvae in the Strait of Sicily was congruent with previous studies conducted on adult populations present in other Mediterranean areas with different molecular markers. The habitat‐specific nature of the morphological variation and the lack of corresponding genetic variation among larvae from the different locations suggested that the observed differences in morphology could be linked to environmental parameters. The body form differences among different larvae samples could reflect the nutritional status of larvae. In fact, these differences were found among anchovy larvae collected in areas with different oxygen and fluorescence, which is an index of primary productivity and is linked to the availability of food for anchovy larvae. 相似文献
158.
159.
Paola Gianella Giancarlo Avallone Claudio Bellino Selina Iussich Chiara Palmieri Paola Roccabianca Claudia Salvadori Renato Zanatta Antonio D��Angelo 《The Canadian veterinary journal. La revue veterinaire canadienne》2012,53(5):549-553
A cutaneous poorly differentiated round cell tumor with concurrent, non-suppurative, polymyositis was diagnosed in a hovawart dog. Histochemical staining, immunohistochemistry, and transmission electron microscopy findings suggested that the tumors cells were of myeloid, or possibly natural killer cell origin. The possibility that the concurrent polymyositis may represent a pre-neoplastic or paraneoplastic process is discussed. 相似文献
160.