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排序方式: 共有116条查询结果,搜索用时 46 毫秒
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Effect of Pimobendan in Dogs with Preclinical Myxomatous Mitral Valve Disease and Cardiomegaly: The EPIC Study—A Randomized Clinical Trial 下载免费PDF全文
A. Boswood J. Häggström S.G. Gordon G. Wess R.L. Stepien M.A. Oyama B.W. Keene J. Bonagura K.A. MacDonald M. Patteson S. Smith P.R. Fox K. Sanderson R. Woolley V. Szatmári P. Menaut W.M. Church M. L. O'Sullivan J.‐P. Jaudon J.‐G. Kresken J. Rush K.A. Barrett S.L. Rosenthal A.B. Saunders I. Ljungvall M. Deinert E. Bomassi A.H. Estrada M.J. Fernandez Del Palacio N.S. Moise J.A. Abbott Y. Fujii A. Spier M.W. Luethy R.A. Santilli M. Uechi A. Tidholm P. Watson 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2016,30(6):1765-1779
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Eight captive-bred horned parakeets (Eunymphicus cornutus) and four captive-bred Major Mitchell cockatoos (Cacatua leadbeateri) from the same aviary tested positive for psittacine circovirus (PsCV) DNA in whole blood by nested-polymerase chain reaction (PCR). The chronic form of disease with feather fragility and loss was observed in three horned parakeets. Infection in other individuals was subclinical. Immunosuppression, either hematologically or as susceptibility to secondary infections, was not observed. Treatment consisted of the administration of beta-(1,3/1,6)-D-glucan from oyster mushroom (Pleurotus ostreatus). Excluding two accidentally dead parakeets, four out of the original six horned parakeets, and all Major Mitchell cockatoos were negative for PsCV DNA in whole blood in 7-9 mo after the treatment was started. Even though the absence of PsCV DNA in blood does not signify elimination of the virus from the whole organism, these preliminary results indicate a possible effect of beta-glucan in the treatment of PsCV infection. To the author's knowledge, this is the first report of PsCV in horned parakeets. 相似文献
4.
László Egyed Anna Nagy András Lakos Viktor Zöldi Zsolt Lang 《Zoonoses and public health》2023,70(1):81-92
The authors analysed epidemiological data of the Hungarian tick-borne encephalitis epidemic from the past seven decades. A total of 911 meningitis serosa cases were described from 1930-1950 s by local hospital physicians, indicating that the virus had been present in the country decades before its official identification in 1952. The virus spread freely in the 1950s–1960s, occupying almost all habitats where ticks occurred in large numbers. The increasing number of cases drove authorities to classify this illness as a notifiable disease in 1977 and to organize the first measures to stop the epidemic. Statistical analysis revealed that the large-scale vaccination launched from the 1990s was responsible for the sharp decrease in the number of human cases from 1997. A significant negative correlation was found between the number of vaccine doses sold and human cases 6 years later. The TBEV endemic area covers 16.57% of the territory and 16.65% of the population of the country. In the last 10 years, 186,000 vaccine doses/year in average were enough to keep the incidence of human TBEV infections between 0.45 and 0.06/100,000 persons. A 20-year-long study found evidence for easing clinical signs in TBEV-infected hospitalized patients. Statistics found a sharp decrease in the number of samples sent for TBEV diagnosis after 1989. Male dominance of patients was characteristic of the epidemics since the 1940s, but now analysis of detailed data from the 1981–2021 period (60.5%–87.5%) proved the statistical significance of this dominance. Obviously, the voluntary vaccination programme was the tool which broke the spread of the epidemic. Widespread public awareness of the disease and the tick vector, probable evolutionary spread of less pathogenic virus strains supplemented with the vaccination campaign led to a negligible level of human TBE cases in Hungary in the last years. 相似文献
5.
Ren Reiser Viktor Stadelmann Peter Weisskopf Lina Grahm Thomas Keller 《植物养料与土壤学杂志》2020,183(3):316-326
Oxygen diffusion rate (ODR) and redox potential (EH) are quantitative indices representing oxygen availability and redox status in soils, which is valuable information for better understanding causes and effects of soil aeration. Because these indices are spatially and temporally highly variable, continuous measurements and adequate numbers of repetitions are essential for accurate in situ monitoring. Here, we present a new, fully automated recording system for in situ measurements where ODR and EH are measured at the same platinum electrode. The conflict between electrode polarization for ODR and the resulting biased EH readings is solved by reducing the polarization time and introducing a recovery interval between two consecutive measurement cycles. The shorter polarization time ensures accurate EH readings. It also results in moderately overestimated ODR readings, but this can be corrected before data analysis. The recovery interval restricts temporal resolution of the EH‐ODR data pairs to 8 h. We illustrate the use of the system with measurements in a field experiment in Zürich, Switzerland. ODR curves at different depths ran roughly parallel to the corresponding curves of O2 concentration in soil air but ODR was much more sensitive to precipitation. Low ODR was a necessary but not a sufficient condition for declining EH. EH ran parallel to O2 concentration in soil air rather than to ODR. The fully automated system allows for time series of replicate measurements in multifactorial field studies with reasonable labor requirements. It may be particularly suitable for studies examining the effects of soil tillage, compaction, and irrigation, where structure‐related soil properties such as porosity, gas permeability, and soil aeration play a dominant role. 相似文献
6.
Szatmári V Osi Z Manczur F 《Journal of the American Veterinary Medical Association》2001,218(11):1796-9, 1778-9
Pyonephrosis refers to suppurative destruction of the parenchyma of the kidney with complete or nearly complete loss of renal function. In dogs, nephrectomy is still the most common treatment for pyonephrosis; however, in the present report, a method for percutaneous ultrasound-guided drainage of the renal pelvis in dogs with pyonephrosis that does not require local or general anesthesia was described, and results of the procedure in 2 dogs were reported. Briefly, dogs were positioned in lateral recumbency with the affected side up, and skin overlying the affected kidney was aseptically prepared. The dilated renal pelvis was punctured percutaneously, under ultrasound guidance, with a 22-gauge needle, and a sample of material was obtained for analysis. The needle was then replaced with an IV catheter, and as much pus as possible was removed from the renal collecting system. A povidone iodine solution was then used to lavage the renal pelvis. Ultrasound-guided drainage and lavage of the renal pelvis was repeated daily until the renal pelvis was so small that it could no longer be punctured. Both dogs recovered and were reported by the owners to be healthy after the procedure. 相似文献
7.
Szatmári V van den Ingh TS Fenyves B Sótonyi P Kótai I Petrási Z Vörös K 《The Veterinary record》2002,150(19):602-605
A two-and-a-half-year-old German shepherd dog with ascites and a high concentration of blood ammonia was investigated. Sonographically, its liver was normal but the portal vein was dilated and the flow of blood within it was slow. A liver biopsy showed that the liver was normal, and did not reveal any possible cause of portal hypertension or ascites. Postmortem, the cranial part of the portal vein was dilated with a cross-striped internal surface, but the caudal part looked normal; there was a stenotic ring between the normal and dilated parts. Histology of the dilated segment revealed marked hypertrophy of both the internal circular and the external longitudinal smooth muscle layers. At the site of the stenosis, the longitudinal muscular layer was replaced by connective tissue. Circumscribed fibrosis in the wall of the portal vein was responsible for the stenosis and the subsequent prehepatic portal hypertension. The cross-striped pattern in the dilated part of the vein was the result of hypertrophy of the inner circular smooth muscle layer. 相似文献
8.
Mario Zauer Simone Hempel Alexander Pfriem Viktor Mechtcherine André Wagenführ 《Wood Science and Technology》2014,48(6):1229-1240
This paper deals with the determination of the pore-size distribution of untreated and thermally modified twin samples of Norway spruce (Picea abies (L.) Karst.) and sycamore maple (Acer pseudoplatanus L.) by means of mercury intrusion porosimetry. The investigations considered oven-dried and at 22 °C and 95 % relative humidity-conditioned samples. A special sample holder and a novel method for evacuation were developed for the measurements. This was necessary both to ensure that samples were positioned at a defined distance and the conditioned samples did not dry in an uncontrolled manner. The results clearly show that the climatic state influences the results. Thermal modification greatly alters the pore-size distribution of spruce. This can be largely attributed to the formation of intercellular spaces in the middle lamella as a result of cell-wall compression due to thermal modification. The alteration of the pore structure of maple due to thermal modification is not as pronounced as that of spruce. 相似文献
9.
Viktor Szatmári DVM Zoltán Harkaanyi MD PhD Károly Vöaröas DVM PhD 《Veterinary radiology & ultrasound》2003,44(4):380-391
Modern ultrasound contrast media are gas-containing stabilized microbubbles that remain intact in the circulating blood for several minutes after intravenous injection and increase the intensity of the backscattered ultrasound. When the microbubbles disappear from the blood, they can be detected in the parenchyma of the liver and the spleen for about 30 more minutes (late liver- and spleen-specific phase). The insonated microbubbles produce second harmonic ultrasound frequencies, whose detection requires nonconventional ultrasound modalities such as pulsed inversion imaging. Nonconventional ultrasound techniques can also be used without microbubbles because second harmonics can be generated by ultrasound in tissues as well. The physical principles and advantages of nonconventional ultrasound techniques are described. The circulating microbubbles can be used not only to enhance weak Doppler signals, but also to perform dynamic contrast studies. Contrast-enhanced dynamic ultrasound studies--similar to contrast-enhanced CT and MRI examinations--have been used in humans to characterize lesions noninvasively (i.e., without biopsies) found during conventional ultrasound examinations. To map the distribution of contrast medium in a nodule or in an organ, specific scanning techniques such as stimulated acoustic emission have been developed. Stimulated acoustic emission occurs when high acoustic pressure ultrasonic waves disrupt the stationary or slowly moving microbubbles. This results in the release of a large amount of harmonic ultrasound frequencies. When the stimulated acoustic emission technique is used for dynamic studies, scanning must be interrupted several times to allow the microvasculature of the lesion to refill with microbubbles (interval delay imaging). The contrast patterns of malignant and benign hepatic nodules in humans have been the most intensively studied. Another type of dynamic study in humans measures the transit time of the contrast medium; that is, how fast the peripherally injected microbubbles reach the hepatic veins. Hepatic cirrhosis can be differentiated from other diffuse parenchymal liver diseases by a shorter transit time. Introducing nonconventional ultrasound techniques and ultrasound contrast media in veterinary diagnostic imaging may have potential value; however, intensive research should be carried out before ultrasound contrast agents can routinely be used in clinical practice. 相似文献
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