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31.
A 5-year-old castrated male Golden Retriever was evaluated for polyuria, polydipsia, and progressive regurgitation thought to be a result of bacterial pyelonephritis and megaesophagus. Bacteriologic culture of urine failed to yield clinically relevant growth, and results of a urine sediment examination were normal. With time, intention tremors and progressive neurologic dysfunction were also observed. At necropsy, a diagnosis of cryptococcal disease was confirmed histologically and immunohistochemically. Findings in the dog of this report were indicative of nephrogenic diabetes insipidus with polyuria and polydipsia caused by cryptococcal pyelonephritis. Neurologic manifestations of systemic cryptococcus infection included megaesophagus, esophageal hypomotility, and regurgitation attributed to localization of cryptococcal organisms in the brain stem in the region of the dorsal motor nucleus of the vagus nerve. To the authors' knowledge, this is the first report of polyuria secondary to cryptococcal pyelonephritis.  相似文献   
32.
A chordoma was removed from the tail base of a 6.5-year-old ferret (Mustela putorius furo). A nodule was observed in the area of tumor development when the ferret was purchased at 3 months of age. Although the nodule did not enlarge for 2 years, slow, steady growth of the tumor was observed for 4 years before surgical removal. Eight months after removal of the chordoma, the ferret developed 2 cutaneous masses. One was adjacent to the vulva, close to where the chordoma had been removed from, whereas the other was in the nasofacial region. After 4 months of slow growth, both masses were removed and both were histologically and immunohistochemically consistent with chordoma. Over the next 8 weeks, additional masses developed in the facial, maxillary gingival, and scapular regions. Enlargement of the gingival mass caused dysphagia, and the ferret was euthanized. Although a necropsy was not performed, these additional masses had a clinical appearance and texture that was similar to the 2 previously removed cutaneous chordomas. To the authors' knowledge, this is the first report of a ferret coccygeal chordoma that developed close to the base of the tail. Ferret chordomas have been reported previously to metastasize to the subcutis overlying the tumor. However, this is the first report of a ferret chordoma that metastasized to a location distant to the primary site of neoplasm development. Cell proliferation indices did not predict this metastatic behavior. It is hypothesized that the long clinical period before removal may have predisposed this neoplasm to metastasis. Observations from this case suggest that chordomas in ferrets may have metastatic potential and so should be removed promptly.  相似文献   
33.
A 4-yr-old striped skunk (Mephitis mephitis) developed an 11- x 7- x 7-cm retroperitoneal mass caudal to the left kidney. The mass was surgically excised and, on the basis of histology and immunohistochemistry, diagnosed as a benign teratoma. Six months later, a second histologically similar neoplasm was excised from the same location and was considered to represent local tumor recurrence. The skunk died 16 mo later without recurrence. Complete excision of the tumor appeared curative in this case and supported the benign diagnosis. An extragonadal teratoma should be considered as a differential diagnosis for an abdominal mass in a skunk.  相似文献   
34.
Acute renal failure was diagnosed in 6 cats that had ingested Easter lily or tiger lily plants. All 6 were treated medically; 2 underwent hemodialysis. Three cats survived the acute episode, and although they had chronic renal failure, they survived for more than 1.5 years. Two cats died despite aggressive medical management, including hemodialysis. One cat was euthanatized shortly after the diagnosis was made. Three of the cats were oliguric or anuric at the time of initial examination, and all 3 died. None of the 3 cats that survived had oliguria or anuria. Various members of the lily family (Liliaceae) can cause nephrotoxicosis in cats, but the toxic principle is not known. Although the prognosis for full recovery of cats with lily toxicosis is poor, long-term survival is possible with supportive care. The prognosis appears to be better for cats with nonoliguric renal failure.  相似文献   
35.
The majority of faculty members in veterinary medicine are white men; the student base, however, is increasingly composed of white women. Faculty and students of color are few. Part of the problem in attracting and retaining new teacher-scholars is that the current generation has different beliefs about the importance of work and home, places dissimilar weights on various workplace dimensions, and has more complicated lives than prior generations of faculty. Thus, a culture clash arises when young faculty work in academic institutions with outmoded policies and practices. This article explores the key aspects of the structure and culture of the academy and offers ideas for making the workplace more attractive to new faculty.  相似文献   
36.
Longline fisheries have expanded throughout the world's oceans since major commercial distant-water pelagic fleets began fishing for tuna and tuna-like species in the early 1950s. Along with the more recent development and expansion of demersal longline fleets for species such as Patagonian toothfish, these vessels are a major source of mortality to several species of seabird. Vessels can set many thousands of baited hooks in a day across many kilometres of water. These waters are often used as foraging areas by wide-ranging seabirds. Attracted by baits and offal, the birds can be caught on the baited hooks and subsequently drown. To provide a greater understanding of the potential impact of the Southern Ocean's longline fleets on seabird populations, this paper describes the trends in longline effort of the major pelagic and demersal fisheries in southern waters. The total reported effort from all longline fleets south of 30°S has been well over 250 million hooks per year since the early 1990s. However the spatial and temporal distribution of this effort has not been constant. While effort from the Japanese pelagic distant-water longline fleet declined through the 1990s, the Taiwanese fleet expanded dramatically. Likewise demersal fishing for toothfish increased markedly during the mid-1990s. These fisheries, along with substantial illegal longline fisheries, may be placing the long-term viability of many Southern Ocean species of seabird in jeopardy.  相似文献   
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38.
There are a number of newly described and emerging disease syndromes affecting the domestic ferret, and the purpose of this article is to make veterinarians aware of these diseases. A recently described systemic coronavirus infection appears to be a variant of the ferret enteric coronavirus and is currently termed “ferret infectious peritonitis.” Disseminated immunopathologic myositis, aplastic anemia/bone marrow aplasia, acute hemorrhagic syndrome, and oral ulcerations are also described, although the exact etiologies for these diseases have yet to be determined. There appears to be at least 2 important amino acid metabolism deficiencies in ferrets: hindlimb weakness in older ferrets (L-carnitine) and cysteine urolithiasis. Ferrets have recently been found to be susceptible to H1N1 influenza, so knowledge regarding this zoonotic disease is essential for veterinarians working with these animals. A novel Mycoplasma spp. has also recently been identified in ferrets with chronic respiratory problems that originated from one breeding colony. Because these diseases are still being investigated, practitioners who treat a ferret patient exhibiting clinical signs consistent with any of the conditions mentioned are encouraged to contact people who are knowledgeable of that particular illness.  相似文献   
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40.
Is calculation possible without language? Or is the human ability for arithmetic dependent on the language faculty? To clarify the relation between language and arithmetic, we studied numerical cognition in speakers of Mundurukú, an Amazonian language with a very small lexicon of number words. Although the Mundurukú lack words for numbers beyond 5, they are able to compare and add large approximate numbers that are far beyond their naming range. However, they fail in exact arithmetic with numbers larger than 4 or 5. Our results imply a distinction between a nonverbal system of number approximation and a language-based counting system for exact number and arithmetic.  相似文献   
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