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91.
Cryptococcus albidus is a saprophytic, encapsulated yeast usually found in air, both outdoor and indoor, and sometimes on human skin. It is not usually considered to be a primary pathogen. Most cryptococcal infections of humans and animals are caused by Cryptococcus neoformans. Several cases of C. albidus infection have been reported in humans over the past 20 years. In the veterinary literature, 2 equine cases have been described: genital infection and mycotic keratitis. The present report is the first documented case of C. albidus systemic infection in a dog. Veterinarians and diagnosticians should be aware that C. albidus may be a potential canine pathogen.  相似文献   
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The study of multiple pathosystems has played a central role in the development of botanical epidemiology, leading to a number of approaches and concepts. Multiple pathosystems are facts, which are experienced by many non-cultivated, or cultivated, plant communities. The shapes and composition of multiple pathosystems vary in space and time because of their inherent structure of relationships, and also in response to management. Examples of variation in multiple pathosystems are given, of groundnut in Côte d’Ivoire, of wheat in Brittany, and of upland rice in northern Laos. Variation in the yield-reducing effects of multiple pathosystems is discussed, including interactions among disease elements, relationships with attainable performances, and linkages with production situations. Progress has been achieved in understanding the links between injury profiles, production situations, and attainable performances. Questions about the functioning and consequences of multiple pathosystems are central to defining the scientific bases for, the design of, and the implementing of IPM. The complexity of multiple pathosystems, however, remains a deterrent, not a challenge, to many plant pathologists. Progress achieved in designing production systems for hardy wheat in France, however, is very promising, because of the multidisciplinary science it involves, and because of the promise to deliver it carries. The concepts of epidemiological guilds and of guilds of harmful agents are offered as perspectives to address and manage syndromes of production and syndromes of disease.  相似文献   
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A 3‐month wild rabbit was presented for examination of ocular opacities in the left eye. A complete bilateral ocular examination including slit‐lamp examination, indirect ophthalmoscopy, tonometry, and ultrasound biomicroscopy was performed. Biomicroscopy of the lens of the left eye showed a retrolental fibrovascular membrane causing leukocoria. The opacity prevented biomicroscopy of the vitreous and funduscopy OS. No other disorder was present in either eye. Ultrasound examination did not show any difference between the right and left eye. Histopathological examination showed a 50‐μm thick, preretinal, retrolental, nonpigmented, fibrovascular tissue. Posterior synechiae were present, but no other lesion of the posterior segment was found in this eye. These ocular abnormalities are consistent with a persistent hyperplastic tunica vasculosa lentis and persistent hyperplastic primary vitreous (PHTVL/PHPV), similar to those described in other species.  相似文献   
96.
Plant disease emergences have dramatically increased recently as a result of global changes, especially with respect to trade, host genetic uniformity, and climate change. A better understanding of the conditions and processes determining epidemic outbreaks caused by the emergence of a new pathogen, or pathogen strain, is needed to develop strategies and inform decisions to manage emerging diseases. A polyetic process-based model is developed to analyse conditions of disease emergence. This model simulates polycyclic epidemics during successive growing seasons, the yield losses they cause, and the pathogen survival between growing seasons. This framework considers one immigrant strain coming in a single event into a system where a resident strain is already established. Outcomes are formulated as probability of emergence, time to emergence, and yield loss, resulting from deterministic and stochastic simulations. An analytical solution to determine a threshold for emergence is also derived. Analyses focus on the effects of two fitness parameters on emergence: the relative rate of reproduction (epidemic speed), and the relative rate of mortality (decay of population between seasons). Analyses revealed that stochasticity is a critical feature of disease emergence. The simulations suggest that: (a) emergence may require a series of independent immigration events before a successful invasion takes place; (b) an explosion in the population size of the new pathogen (or strain) may be preceded by many successive growing seasons of cryptic presence following an immigration event; and (c) survival between growing seasons is as important as reproduction during the growing season in determining disease emergence.  相似文献   
97.
This paper provides reviews of the most commonly used methods to detect plant pests belonging to groups of invasive organisms with high economic relevance, including Coleoptera (bark beetles, flathead borers, leaf beetles, longhorn beetles, weevils), Diptera (cone and seed flies, fruit flies), Homoptera (aphids, leafhoppers and psyllids, whiteflies), Lepidoptera (moths and butterflies), Thysanoptera (thrips), bacteria (potato brown rot Ralstonia solanacearum) and fungi (pitch canker disease Gibberella circinata, brown rot disease Monilinia fructicola). Future perspectives in detection methods are discussed, with particular reference to the considerable increase in the volume, commodity type and origins of trade in plant material from third countries, the introduction of new crops, the continuous expansion of the EU with new border countries being added, and the impact of climate change affecting the geographical boundaries of pests and their vectors.  相似文献   
98.
The current study aimed to explore the potential usefulness of liquid or lyophilized egg yolk plasma (EYP) as a substitute for low‐density lipoproteins (LDL) for cryopreservation of canine spermatozoa. In the first experiment, a total of 20 ejaculates harvested from six Beagles were frozen in extenders containing 6% LDL (control) or liquid or lyophilized EYP at one of three concentrations (20%, 40% or 60%). Motility parameters were assessed 10 min after thawing using computer‐assisted sperm analysis. For both liquid and lyophilized EYP, the 40% concentration yielded motility similar (p > 0.05) to that observed with the control extender. In the second experiment, 12 ejaculates collected from the same six dogs were frozen in 6% LDL (Control), 40% liquid EYP or 40% lyophilized EYP extenders. Spermatozoal membrane integrity (hypo‐osmotic swelling test [HOSt] and SYBR14/propidium iodide [PI] staining), acrosome integrity (FITC‐Pisum sativum agglutinin staining) and DNA integrity (acridine orange staining) characteristics were evaluated 10 min after thawing. Both liquid and lyophilized 40% EYP‐based extenders successfully preserved all assessed integrity parameters as efficiently as the control. Results of this study suggest that lyophilized EYP is a viable alternative to LDL in freezing extenders for dog semen.  相似文献   
99.
Eleven samples of grapes and musts used in red table wines were investigated for the occurrence of potential ochratoxin A (OTA)-producing molds. From these samples, 59 filamentous fungi and 2 yeasts were isolated. Among the 30 genera isolated, Deuteromycetes were the most frequent (70%) followed by Ascomycetes (10%). Six of the eleven grapes samples were contaminated by potentially ochratoxinogenic strains (Penicillium chrysogenum and Aspergillus carbonarius). When cultivated in vitro on solid complex media, the 14 strains of A. carbonarius produced OTA. No other species produced OTA under the same conditions. Among must samples, eight of eleven were found to be contaminated by OTA (concentrations from <10 to 461 ng/L). There is a strong correlation between the presence of ochratoxin-producing strains on grapes and OTA in musts. These findings should be connected with the OTA contamination of human blood in these areas and in France.  相似文献   
100.
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