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51.
52.
Anthony Claes Barry A. Ball Cynthia J. Corbin Alan J. Conley 《Journal of Equine Veterinary Science》2014
Cryptorchidism is a developmental disorder which can be diagnosed by a variety of different tests. Still, equine field veterinarians often rely on endocrine markers to detect retained testicular tissue. This report describes the value of anti-Müllerian hormone (AMH) as a diagnostic marker for cryptorchidism in three stallions suspected of cryptorchidism, with equivalent serum testosterone concentrations. A single measurement of AMH identified cryptorchidism, with inconclusive testosterone concentrations as either gelding or stallion. Furthermore, a human chorionic gonadotropin (hCG) stimulation test or surgery was performed to support the diagnostic value of AMH. To conclude, the endocrine panel for cryptorchidism should be expanded to include determination of serum AMH, as this determination can increase the diagnostic accuracy of a single blood sample. 相似文献
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K. Sjstrand G. Wess I. Ljungvall J. Hggstrm A‐C. Merveille M. Wiberg V. Gouni J. Lundgren Willesen S. Hans A‐S. Lequarr L. Mejer Srensen J. Wolf L. Tiret M. Kierczak S. Forsberg K. McEntee G. Battaille E. Seppl K. Lindblad‐Toh M. Georges Hannes Lohi V. Chetboul M. Fredholm K. Hglund 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(2):451-457
Background
Measurement of plasma concentration of natriuretic peptides (NPs) is suggested to be of value in diagnosis of cardiac disease in dogs, but many factors other than cardiac status may influence their concentrations. Dog breed potentially is 1 such factor.Objective
To investigate breed variation in plasma concentrations of pro‐atrial natriuretic peptide 31‐67 (proANP 31‐67) and N‐terminal B‐type natriuretic peptide (NT‐proBNP) in healthy dogs.Animals
535 healthy, privately owned dogs of 9 breeds were examined at 5 centers as part of the European Union (EU) LUPA project.Methods
Absence of cardiovascular disease or other clinically relevant organ‐related or systemic disease was ensured by thorough clinical investigation. Plasma concentrations of proANP 31‐67 and NT‐proBNP were measured by commercially available ELISA assays.Results
Overall significant breed differences were found in proANP 31‐67 (P < .0001) and NT‐proBNP (P < .0001) concentrations. Pair‐wise comparisons between breeds differed in approximately 50% of comparisons for proANP 31‐67 as well as NT‐proBNP concentrations, both when including all centers and within each center. Interquartile range was large for many breeds, especially for NT‐proBNP. Among included breeds, Labrador Retrievers and Newfoundlands had highest median NT‐proBNP concentrations with concentrations 3 times as high as those of Dachshunds. German Shepherds and Cavalier King Charles Spaniels had the highest median proANP 31‐67 concentrations, twice the median concentration in Doberman Pinschers.Conclusions and Clinical Importance
Considerable interbreed variation in plasma NP concentrations was found in healthy dogs. Intrabreed variation was large in several breeds, especially for NT‐proBNP. Additional studies are needed to establish breed‐specific reference ranges. 相似文献54.
Abstract – We present a functional response model that primarily evaluates effects of satiation in piscivore prey-size selection. The model also includes other passive processes, such as prey-size-dependent encounter rate and prey-size-dependent capture success, where capture success decreases and encounter rate increases with prey size. The model generates a wide variety of outcomes, where small, intermediate or large prey is positively selected for. These very different selectivity patterns are generated without any active prey choice included in the model. The results stress the importance of controlling for satiation and other passive processes in empirical studies on prey-size selection, especially if the aim is to test active prey choice in piscivores. 相似文献
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From mid-2004 to mid-2005, several grass carp, Ctenophayngodon idella (Valenciennes), showing evidence of spinal deformity were presented to the Aquatic Animal Health Program, Cornell University. The carp were from three separate locations in New York State. The first case involved several fish from a natural body of water in the Catskill Mountain region of south-eastern New York State. The second was a single affected individual from a private pond in the Fingerlakes region of Central New York State. The third was a single individual from the Cold Springs Harbor Fish Hatchery, Cold Springs Harbor, Long Island. All fish were at least 7 years of age. Radiographs and computed tomography (CT) scans revealed the deformities to be of bony origin. The spinal deformities were characterized by variable amounts of kyphosis, scoliosis and rotation. While it is not possible to determine the specific cause(s) of the lesions, we consider a genetic component as a likely contributor to the observed pathology. 相似文献
57.
The studies reviewed here evaluated the role cellular immune system components play in control of brucellosis by conducting comparative studies with brucella-resistant C57BL/10 or C57BL/6 mice and susceptible BALB/c mice. We have shown by both in vitro and in vivo studies that activation of macrophages with interferon-gamma (IFN-γ) is an important factor for control of infection with B. abortus in the mouse model and that the mechanism of anti-brucella activity largely involved reactive oxygen intermediates. Differences in control of the organism by resistant and susceptible mice was not related to inherent differences in the ability of their macrophages to control infection either with or without IFN-γ activation nor was it attributable to NK cells since we found no role for them in control of brucellosis in either mouse strain. However, relative resistance to brucellosis did correlate with increased production of IFN-γ by CD4 T cells during the first weeks after infection while IL-10 contributed to susceptibility in BALB/c mice. Moreover, by 3 weeks post-infection splenocytes from the susceptible BALB/c mice failed to produce IFN-γ and relied on TNF- as well as CD8 T cells to control infection until the end of the plateau phase around 6 weeks post-infection when IFN-γ production resumed and clearance began. In contrast, IFN-γ was crucial for control throughout the infection in the more resistant C57BL/6 mice and the mice died in its absence by 6 weeks post-infection compared to 12 weeks for the more susceptible mice that relied on additional mechanisms of control. In contrast to the IFN-γ knock-out mice, both β2 microglobulin knock-out C57BL/6 mice, which do not express conventional MHC class I molecules and thus cannot present antigen to CD8 T cells, or perforin knock-out C57BL/6 mice, which have no T cell cytotoxic activity, controlled and cleared the infection as well as normal C57BL/6 mice. The hiatus of IFN-γ production in BALB/c mice correlated with very high levels of total IL-12 and it was postulated that the lack of IFN-γ was a consequence of p40 homodimer blocking activity. However, reduction of p40 IL-12 in vivo through administration of indomethacin reduced the infection without a concomitant measurable increase in IFN-γ. Current studies are aimed at elucidating the mechanism of the IFN-γ hiatus. 相似文献
58.
G. Wolf 《European journal of plant pathology / European Foundation for Plant Pathology》1968,74(1):19-23
32P administered to wheat plants for 2 h just before inoculation with stem rust, and extracted from the primary leaves 2 and 4 days later, was partly incorporated in highmolecular RNA; the specific activity of this fraction in rust-infected leaves was significantly higher than that in healthy leaves.When administered for 1 1/2 h 2 and 4 days after inoculation and extracted immediately thereafter, large amounts of32P were incorporated in a polyphosphate fraction; also in this case the specific activity of this fraction was significantly higher in rustinfected leaves than in healthy leaves. It could not be associated with a distinct RNA fraction, nor could short-living m-RNA be detected in other fractions. 相似文献
59.
ABSTRACT The effect of variable temperature on the infection severity of Podosphaera macularis was investigated. Potted 'Symphony' hop plants were inoculated and exposed to different temperature regimes that included supraconducive temperatures (30 to 42 degrees C) for varying periods of time (2 to 9 h). Infection severity (lesions per cm(2) of leaf area) was calculated 7 to 10 days after inoculation. Immediately exposing inoculated plants to 30 degrees C for as little as 2 h significantly (P = 0.05) reduced infection severity compared with exposure at a constant 18 degrees C. However, exposure of inoculated plants to optimal conditions for 24 or 48 h prior to exposure to supraconducive conditions reduced this effect for plants exposed to 30, 33, or 36 degrees C. Exposure to 39 or 42 degrees C for 2 or more hours resulted in infection frequencies not significantly different from that of the uninoculated control regardless of prior exposure to favorable conditions. Exposure to simulated field temperatures programmed into growth chambers indicated that inoculation at 1700 or 2100 h resulted in significantly more disease than did inoculation at 0900 or 1300 h. Plants exposed to supraconducive or simulated field temperatures for 7 days prior to inoculation developed significantly lower disease severity than did plants maintained at 18 degrees C for 7 days. The magnitude, length, and time of exposure to supraconducive temperatures in relation to time of inoculation plays an important role in the development of hop powdery mildew, and rules addressing these variables could be a useful addition to disease risk assessment models. 相似文献
60.