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51.
The use of personal protective equipment by veterinary workers during radiographic imaging is inconsistent. While the self‐reported use of leaded aprons and thyroid shields approaches 100% in some studies, the use of leaded gloves and eyeglasses is much lower. Previous studies describing personal protective equipment use are based on self‐reporting. Objectives of this prospective, observational study were to describe use of leaded personal protective equipment during radiographic imaging by veterinary workers, and to compare observed use with self‐reported use. Use of leaded personal protective equipment during radiographic imaging by veterinary workers was observed over a 10 week period using two motion‐triggered video cameras, and a questionnaire was then completed by workers on their use of personal protective equipment. Workers restrained the animal during 91.8% (753/820) of exposures. An apron and a securely closed thyroid shield were worn for >99% of studies. Gloves were used correctly for 43.6% (156/358) of radiographic studies. Leaded eyeglasses were worn for 1.7% (6/358) of studies. Correct glove use was more frequent during regular working hours than after‐hours for both veterinarians (odds ratio 32.7, P = 0.001) and veterinary students (odds ratio 75.1, P < 0.001). The number of workers in the room was lower when animals were sedated (P = 0.002) or anesthetized (P = 0.017). Workers overestimated their frequency of glove use (P <0.001). In conclusion, workers use personal protective equipment less frequently in an unsupervised environment, and overestimate their use of personal protective equipment. Use of sedation or anesthesia decreases worker exposure to ionizing radiation.  相似文献   
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The cover image, by Alexandra Keller et al., is based on the Original Article The JAK2/STAT5 signaling pathway as a potential therapeutic target in canine mastocytoma, DOI: 10.1111/vco.12311

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A 16-y-old female Sumatran tiger (Panthera tigris sumatrae) was evaluated for hyporexia. Examination revealed chronic kidney disease and a large subcutaneous axillary mass with draining tracts that contained numerous small black grains. Histologic examination revealed the presence of intralesional fungal hyphae. Persistent hyporexia and pyogranulomatous disease, as well as progressive cachexia and azotemia occurred despite treatment, and euthanasia was performed. Disseminated phaeohyphomycosis was diagnosed on postmortem examination, additionally affecting various lymph nodes, the nasal cavity, mesenteric adipose tissue, abdominal aorta, pericardium, and kidney. Fungal culture from a deep-tissue sample isolated a pure growth of Curvularia sp., a dematiaceous opportunistic fungus able to cause eumycetomas and/or phaeohyphomycosis. Phaeohyphomycosis is a rare but emerging condition, not previously reported as disseminated disease in an exotic carnivore, to our knowledge. Aggressive systemic antifungal treatment was unsuccessful, likely complicated by diagnostic challenges and concurrent renal disease. The presence of a swelling with abundant grains exiting draining tracts should direct clinicians to the diagnosis of a mycetoma, warranting early and aggressive treatment.  相似文献   
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The spectral data of a new Δ7,22 sterol, 24S-ethyl-5α-cholesta-7,22E-dien-3α-ol β-galactopyranoside, isolated from the bulbs of Autonoë madeirensis, are reported.  相似文献   
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Two aqueous fixation methods (modified Davidson's solution and modified Davidson's solution with 2% (w/v) Alcian blue) were compared against two non‐aqueous fixation methods (methacarn solution and methacarn solution with 2% (w/v) Alcian blue) along with the standard buffered formalin fixation method to (a) improve preservation of the mucous coat on Atlantic salmon, Salmo salar L., gills and (b) to examine the interaction between the amoebae and mucus on the gill during an infection with amoebic gill disease. Aqueous fixatives demonstrated excellent cytological preservation but failed to deliver the preservation of the mucus when compared to the non‐aqueous‐based fixatives; qualitative and semi‐quantitative analysis revealed a greater preservation of the gill mucus using the non‐aqueous methacarn solution. A combination of this fixation method and an Alcian blue/Periodic acid–Schiff staining was tested in gills of Atlantic salmon infected with amoebic gill disease; lectin labelling was also used to confirm the mucus preservation in the methacarn‐fixed tissue. Amoebae were observed closely associated with the mucus demonstrating that the techniques employed for preservation of the mucous coat can indeed avoid the loss of potential mucus‐embedded parasites, thus providing a better understanding of the relationship between the mucus and parasite.  相似文献   
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The aim of this study was to quantify the importance of population density on the growth and survival of juvenile red swamp crayfish, Procambarus clarkii (Girard), and to understand the effects of density on both the period between moults and the increment per moult at high densities without food limitation. A laboratory experiment was performed to determine growth and survival of juvenile crayfish at five densities (20, 40, 60, 80 and 100 crayfish m?2). Density clearly affected crayfish growth. The impact of density on final weight was higher than on total length increase, growth rate and final length (FL) (by decreasing order of effect). When comparing minimum and maximum densities, we observed that FL suffered a 34% reduction. Number of moults, mean intermoult period (IP) and survival were not significantly affected by density. Our results indicated that the IP and the percentage of increment per moult are affected by the size of crayfish before moult and we provide equations for these relations. Our findings are relevant both for crayfish aquaculture management and for the management of wild or harvested rice‐field crayfish populations.  相似文献   
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The aim of the present study was to analyse the occurrence of chlamydiae in several mammalian host species. Clinical samples that previously tested positive in a Chlamydiaceae-specific real-time PCR were retested using six species-specific real-time PCR assays to identify the chlamydial species involved. Chlamydophila (Cp.) abortus was the agent most frequently found in cattle, sheep, horses, goats, and pigs. Detection in cattle of Cp. psittaci (11% of samples) and Chlamydia (C.) suis (9%), as well as Cp. psittaci in a goat sample was somewhat unexpected. DNA of two different chlamydiae was identified in 56 (12.7%) of 440 samples tested. Cp. felis was the predominant species found in cats, while in guinea pigs and rabbits only Cp. caviae was detected. Interestingly, the latter two pathogens were also identified in samples from dogs. The data show that mixed chlamydial infections are not rare and suggest an extended host range of individual species.  相似文献   
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