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81.
OBJECTIVE: To compare the histologic appearance of canine skin biopsies collected by use of a scalpel, skin biopsy punch, monopolar electrosurgery, CO2 laser, and radio wave radiosurgery in fully rectified wave form (RWRS). STUDY DESIGN: Experimental, randomized design. ANIMALS: Healthy adult grayhounds (n=4). METHODS: Skin biopsies were collected using 5 techniques. Cut margins of biopsy specimens and adjacent peripheral skin were evaluated using light microscopy to compare penetration of the dermis by tissue carbonization (char). RESULTS: No char occurred in skin specimens collected by biopsy punch and scalpel. Char penetration occurred in all specimens collected by electrosurgery, CO2 laser, and RWRS. Mean char penetration in skin biopsies collected by RWRS (0.158 mm) was significantly less than for monopolar electrosurgery (0.223 mm) and CO2 laser (0.215 mm). Mean char penetration in adjacent peripheral skin surrounding biopsies collected by RWRS (0.171 mm) was significantly less than monopolar electrosurgery (0.255 mm) but not less than CO2 laser (0.215 mm, P<.07). CONCLUSIONS: RWRS (blended waves in cut-coagulate mode) caused less lateral thermal damage to canine skin biopsies than monopolar electrosurgery and CO2 laser and less lateral thermal injury to peripheral skin than monopolar electrosurgery. CLINICAL RELEVANCE: Excision of canine skin biopsies with heat-generating devices may not allow reliable histologic interpretation, particularly when assessing margins of small biopsy specimens. RWRS may be less traumatic to canine skin than monopolar electrosurgery and CO2 laser when used to make incisions.  相似文献   
82.
This article describes amebic infections in 4 horses: granulomatous amebic encephalitis caused by Balamuthia mandrillaris and Acanthamoeba culbertsoni and systemic infections caused by Acanthamoeba sp. The former infection occurred in 1 of 4 horses spontaneously without any underlying conditions; the latter amebic infection was perhaps "opportunistic" considering the visceral involvement by this protozoan in association with Aspergillus sp. and/or Escherichia coli and Pseudomonas sp. The clinicopathologic findings and demonstration of the amebic organisms using immunohistochemical techniques, culture, polymerase chain reactions, and electron microscopy are presented.  相似文献   
83.
The precise determination of the embryonic chronology is very important in reproductive biotechnologies, especially in estimating embryonic age. Thus, there is a need for greater knowledge and standardization for determining the chronology of embryonic development and functional morphology. We describe aspects of embryonic development in two domestic carnivores to add knowledge about organ peculiarities and for application in veterinary practice, in prenatal development and in the biotechnology fields. We found that the development of differential characteristics of embryonic organs occurs in the first trimester of pregnancy for both species. Thus, using the combination of the crown‐rump length, macroscopic analysis and optical microscopy, it is possible to predict gestational age more precisely in animals that lack a defined breed and establish an embryonic pattern.  相似文献   
84.
Simultaneous global measurements of nitric acid (HNO(3)), water (H(2)O), chlorine monoxide (CIO), and ozone (O(3)) in the stratosphere have been obtained over complete annual cycles in both hemispheres by the Microwave Limb Sounder on the Upper Atmosphere Research Satellite. A sizeable decrease in gas-phase HNO(3) was evident in the lower stratospheric vortex over Antarctica by early June 1992, followed by a significant reduction in gas-phase H(2)O after mid-July. By mid-August, near the time of peak CIO, abundances of gas-phase HNO(3) and H(2)O were extremely low. The concentrations of HNO(3) and H(2)O over Antarctica remained depressed into November, well after temperatures in the lower stratosphere had risen above the evaporation threshold for polar stratospheric clouds, implying that denitrification and dehydration had occurred. No large decreases in either gas-phase HNO(3) or H(2)O were observed in the 1992-1993 Arctic winter vortex. Although CIO was enhanced over the Arctic as it was over the Antarctic, Arctic O(3) depletion was substantially smaller than that over Antarctica. A major factor currently limiting the formation of an Arctic ozone "hole" is the lack of denitrification in the northern polar vortex, but future cooling of the lower stratosphere could lead to more intense denitrification and consequently larger losses of Arctic ozone.  相似文献   
85.
86.
A 10‐year‐old, clinically healthy, male dromedary camel had presented a history of progressive unilateral testicular enlargement over the past 5 years. The animal had mated with 32 females during that period; all had conceived. The sex ratio of his offspring was one male to 31 females. Ultrasound examination of the right testicle revealed a diffusely heterogeneous parenchyma with no identifiable normal testicular tissue. The enlarged testicle was surgically removed. Macroscopically, the testicle had a glistening pink surface and contained multiple soft, bulging nodules. Histopathologically, a well‐differentiated, diffuse seminoma was diagnosed. In conclusion, this study describes the fertility, sex ratio, clinical findings and ultrasonographic imaging in a male dromedary camel affected with unilateral testicular seminoma.  相似文献   
87.
Abstract

CASE HISTORY: Ovariohysterectomy was performed on an adult Cavalier King Charles Spaniel. The skin that had been clipped for surgery was noticed to be erythematous 8 days later.

CLINICAL AND PATHOLOGICAL FINDINGS: Poorly defined patches containing multiple papules were visible bilaterally within the clipped skin. These became larger over the following 2 weeks, and samples were collected for histology. Seven days later, the lesions were multiple raised masses, up to 5 cm in diameter. Histology revealed numerous cup-shaped epidermal proliferations extending into the dermis. The presence of keratinocytes with increased quantities of blue-grey cytoplasm, and koilocytosis suggested papillomavirul infection; Canis familiaris papillomavirus (CfPV-2) DNA was amplified from two separate samples. Complete regression was observed 8 weeks after the lesions had been initially observed.

DIAGNOSIS: Multiple inverted papilloma confined to skin that had been clipped for surgery.

CLINICAL RELEVANCE: This is the first time that the development of canine cutaneous papillomas has been associated with surgery. The nature of the association between surgery and development of the papillomas is uncertain. However, it is possible that damage to superficial skin could promote the formation of papillomas. This is the first identification of CfPV-2 in New Zealand.  相似文献   
88.
89.
The DVM program at the University of Calgary offers a Clinical Skills course each year for the first three years. The course is designed to teach students the procedural skills required for entry-level general veterinary practice. Objective Structured Clinical Examinations (OSCEs) were used to assess students' performance on these procedural skills. A series of three OSCEs were developed for the first year. Content was determined by an exam blueprint, exam scoring sheets were created, rater training was provided, a mock OSCE was performed with faculty and staff, and the criterion-referencing Ebel method was used to set cut scores for each station using two content experts. Each station and the overall exam were graded as pass or fail. Thirty first-year DVM students were assessed. Content validity was ensured by the exam blueprint and expert review. Reliability (coefficient α) of the stations from the three OSCE exams ranged from 0.0 to 0.71. The three exam reliabilities (Generalizability Theory) were, for OSCE 1, G=0.56; OSCE 2, G=0.37; and OSCE 3, G=0.32. Preliminary analysis has suggested that the OSCEs demonstrate face and content validity, and certain stations demonstrated adequate reliability. Overall exam reliability was low, which reflects issues with first-time exam delivery. Because this year was the first that this course was taught and this exam format was used, work continues in the program on the teaching of the procedural skills and the development and revision of OSCE stations and scoring checklists.  相似文献   
90.
The objectives of this investigation were to understand transplacental transport of iron by secreted uteroferrin (UF) and haemophagous areas of water buffalo placenta and clarify the role(s) of blood extravasation at the placental‐maternal interface. Placentomes and interplacentomal region of 51 placentae at various stages of gestation were fixed, processed for light and transmission electron microscopy, histochemistry and immunohistochemistry. Haemophagous areas were present in placentomes collected between 4 and 10 months of pregnancy. Perl’s reaction for ferric iron was negative in placentomes, but positive in endometrial glands. Positive staining for UF indicated areas in which it was being taken up by phagocytosis and/or fluid phase pinocytosis in areolae of the interplacentomal mesenchyme, with little staining in endometrial stroma. Imunohistochemistry detected UF in trophectoderm of haemophagous regions of placentomes and in other parts of the foetal villous tree, but the strongest immunostaining was in the epithelial cells and lumen of uterine glands. Ultrastructural analyses indicated that erythrophagocytosis was occurring and that erythrocytes were present inside cells of the chorion that also contained endocytic vesicles and caveolae. Results of this study indicate that both the haemophagous areas of placentomes and the areolae at the interface between chorion and endometrial glands are important sites for iron transfer from mother to foetal‐placental tissues in buffalo throughout pregnancy.  相似文献   
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