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31.
32.
CASE HISTORY A 15-year-old, brown-and-white cat was presented to a veterinary clinic with an ulcerated, reddened 1-cm diameter lesion on the nasal planum.

CLINICAL FINDINGS AND DIAGNOSIS: Histology of a biopsy sample confirmed the lesion was a squamous cell carcinoma (SCC). PCR amplified DNA sequences from two different papillomaviruses. One sequence was from FdPV 2, which has previously been amplified from feline cutaneous SCC. However, the other sequence has not previously been reported, suggesting a novel feline papillomavirus.

CLINICAL RELEVANCE: There is evidence that papillomaviruses promote the development of SCC on sun-exposed skin in humans. This is the first report in a cat of a papillomavirus other than FdPV2 and the first time that multiple papillomaviruses have been detected within a single neoplasm in this species. Whether the papillomaviruses influenced the development and behaviour of this SCC is currently uncertain, but this case provides additional evidence of the association between papillomaviruses and feline cutaneous SCC. If papillomaviruses are found to influence the development of SCC this may allow novel strategies to prevent these common neoplasms in cats.  相似文献   
33.
A superconducting point contact is used to determine the spin polarization at the Fermi energy of several metals. Because the process of supercurrent conversion at a superconductor-metal interface (Andreev reflection) is limited by the minority spin population near the Fermi surface, the differential conductance of the point contact can reveal the spin polarization of the metal. This technique has been applied to a variety of metals where the spin polarization ranges from 35 to 90 percent: Ni0.8Fe0.2, Ni, Co, Fe, NiMnSb, La0.7Sr0.3MnO3, and CrO2.  相似文献   
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35.
Analyses of stable carbon isotopes from two sample suites from sandstone uranium (tabular) ores show interesting variations. Organic carbon associated with high-grade uranium ore is heavy (delta(13)C = -16.9 to -19.6 per mil, where delta(13)C = (13)C/(12)C relative to the Pee Dee belemnite standard) relative to the adjacent lower-grade samples (-22.7 to -26.4 per mil). It is suggested that the heavy isotopic values for the are samples are related to a radiation and chemical isotope effect that has occurred mainly because of an alpha-radiation dose of 10(11) rads.  相似文献   
36.

Background

Multiple sclerosis (MS), Hashimoto's disease and Graves' disease are autoimmune diseases that may share similar pathogenic mechanisms. The co-occurrence rates and demographic characteristics of Graves' disease and Hashimoto's disease (HT) in our MS population are compared with the general population.

Methods

The prevalence of thyroid disease in our MS patients was determined by chart review and survey. Previous diagnosis of thyroid disease, age at diagnosis, treatment used, and about the use of disease modifying medications used to treat their MS were asked. Chart reviews were used to estimate the population prevalence of Graves' disease and Hashimoto's disease and to estimate the demographics of patients with thyroid disease.

Results

A significant co-occurrence of Graves' disease with MS (p = 0.002), and a non-significant co-occurrence of Hashimoto's disease were noted (p = 0.097). No difference in the age of onset or gender of thyroid disease in MS patients compared to the general population was found.

Conclusion

There is a significant co-occurrence in patients with MS and Graves' disease, and a trend to co-occurrence in patients with MS and Hashimoto's disease. There are no differences in the demographics of patients with thyroid disease in our MS patients compared to the general population.
  相似文献   
37.
Objective To document an ovine disease attributed to the consumption of Lythrum hyssopifolia (lesser loosestrife). Procedures Historical and histological review of field and experimental cases. Results 1–20% mortality occurred in sheep flocks grazing paddocks where L. hyssopifolia was the predominant green vegetation. Well‐documented disease outbreaks occurred in summer on nine farms across Victoria between 1974 and 2002. Liver damage occurred in all nine outbreaks, with kidney damage in at least eight. Hepatocyte necrosis was usually zonal to midzonal (zone 2) in the liver samples from four farms and periacinar (zone 3) in those from three farms, but some livers showed only single‐cell necrosis. Multinucleate hepatocytes near necrotic areas were a feature in six cases. Proximal tubular epithelium appeared to be the primary renal target and brown granules were often present in renal tubules. Biochemical and histological evidence of liver and kidney damage was obtained from two sheep experimentally pen‐fed harvested L. hyssopifolia. Conclusion Chemicals in L. hyssopifolia are toxic to ovine hepatocytes and renal tubular epithelial cells.  相似文献   
38.
Abstract

CASE HISTORY: A 2-year-old Hereford bull was lame for one week before becoming recumbent.

CLINICAL AND PATHOLOGICAL FINDINGS: The scrotum and ventral perineal region were cold and blackened caudally. The semimembranosus and semitendinosus muscles were firm on palpation. The bull was subject to euthanasia, and necropsy revealed that the skin and S/C tissues of the caudal half of the scrotum were grey and necrotic. The caudal and distal aspects of the semimembranosus and semitendinosus muscles were grey and necrotic to a depth of approximately 15 cm, and these changes appeared to track along fascial planes. The tissue had an offensive smell, and large amounts of flocculent, watery, brown fluid and some gas were present. Histology of affected muscle and S/C tissues revealed coagulative necrosis, with oedema and large numbers of bacteria that were predominantly Gram-positive rods. Adjacent blood vessels contained thrombi while the epidermis overlying the affected areas appeared diffusely necrotic, suggesting infarction. Culture of the fluid yielded a pure growth of Arcanobacterium spp., which was identified as Arcanobacterium haemolyticum, using an API Coryne biochemical test strip.

DIAGNOSIS: Necrotising fasciitis and myositis due to Arcanobacterium haemolyticum.

CLINICAL RELEVANCE: Arcanobacterium haemolyticum has not previously been reported as a cause of necrotising fasciitis in any species. Necrotising fasciitis is probably an under-reported condition in cattle due to its clinical similarity to clostridial disease.  相似文献   
39.
A 6-y-old female dromedary camel (Camelus dromedarius L.) was presented for assessment of firm, bilateral swellings rostral and ventral to the eyes. Serum biochemistry revealed hyperglycemia (28.5 mmol/L), hypocalcemia (1.27 mmol/L), hyperphosphatemia (3.39 mmol/L), hypoproteinemia (total protein 50 g/L), and hypoalbuminemia (20 g/L). Based on the poor prognosis associated with the presumptive diagnosis of fibrous osteodystrophy, the camel was euthanized. Gross postmortem findings revealed expanded fibrous tissue replacing the maxilla and mandible, and bilaterally prominent parathyroid glands. Histology of the maxilla revealed proliferative loose fibrous tissue with widely scattered, regularly spaced, small spicules of mineralized bone. The parathyroid glands were prominent bilaterally; the internal and external parathyroid glands were composed of plump cells with abundant pale basophilic cytoplasm and open nuclei. The pathologic findings were consistent with the antemortem diagnosis of fibrous osteodystrophy. The camel’s diet, which was not specifically balanced for a camel, included grass hay, sweet feed, and alfalfa pellets. The camel’s caregivers reported feeding her treats of cookies. A feed analysis was not available. The biochemistry abnormalities and clinical and postmortem findings, along with a diet that was not balanced for a camel, are consistent with a diagnosis of nutritional secondary hyperparathyroidism.  相似文献   
40.
Parthenote embryos are being considered as an alternative source of embryonic stem cells. However, as there is still a dearth of knowledge of this kind of embryos, a better understanding of their biology is needed for their application. In this work, we studied the differences and similarities between parthenotes and normal embryos at the blastocyst stage in vivo developed. We analysed the expression of factor OCT‐4, vascular endothelial growth factor (VEGF), insulin‐like growth factor I (IGF‐I) and uteroglobin (UG) by real‐time PCR. To do so, oocytes were recovered and after activation procedure were transferred by ventral middle laparoscopy to receptive does to undergo completely in vivo development. Does were slaughtered 6 days post‐ovulation induction, and parthenote and normal embryos were recovered for mRNA expression analysis. Our results reported that parthenotes and normal embryos showed similar mRNA expression for OCT‐4 and VEGF. However, IGF‐I and UG showed to be over‐expressed in parthenote embryos. Thus, our study highlights that despite the in vivo development of parthenotes, they still seem to have an altered expression and, therefore, to be different to normal embryos. The altered expression pattern of parthenote embryos suggests that these embryos should be studied carefully before future application.  相似文献   
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