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181.
Abstract— —The paper summarizes the functional anatomy of the kidney in terms of (a) the arterial vascular supply (b) the glomeruli (c) the tubules and interstitial tissues. Common pathological lesions of these parts and their possible functional effects are discussed. Résumé— —L'article résume l'anatomie fonctionnelle du rein en termes de (a) la provision vasculaire artérielle, (b) les glomérules, (c) les tubes et le tissu interstitiel. Les lésions pathologiques communes de ces éléments et leurs possible effet fonctionnel sont discutés. Zusammenfassung— —Der Artikel fasst die funktionelle Anatomie der Niere zusammen und bespricht (a) die arterielle Blutversorgung, (b) die Glomeruli und (c) die Tubuli und das interstitielle Gewebe. Uebliche pathologische Veraenderungen dieser Teile und ihre zu erwartenden funktioneilen Wirkungen werden besprochen.  相似文献   
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Central nervous system (CNS) tissues from 192 cats with neurological signs were examined histologically, and tissues from 173 of them were later examined immunohistochemically as part of a survey to determine the prevalence of feline spongiform encephalopathy (FSE). One of the cats was from Norway and the others were from Great Britain. The most commonly recorded clinical signs were ataxia, behavioural changes and epilepsy, but none of the cats had histopathological evidence of FSE. The most common organic CNS lesions were non-suppurative encephalomyelitis in 28 per cent, neoplasia in 15 per cent and a heterogeneous group of degenerative encephalopathies in 9 per cent of the cats. A range of minor histological lesions of uncertain significance was also observed. No histological lesions were observed in the tissues of 63 (33 per cent) of the cats. Disease-specific prion protein (PrP(Sc)) was observed in only one of the 173 cats examined by immunohistochemistry.  相似文献   
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The therapeutic efficacy and field safety of tulathromycin were evaluated in stocker calves with undifferentiated bovine respiratory disease (BRD) in three field studies conducted over two consecutive grazing seasons in Nebraska. Eight hundred calves exhibiting clinical signs of BRD and with rectal temperatures of 104 degrees F or higher were treated with tulathromycin (n = 340), florfenicol (n = 240), or tilmicosin (n = 220) and evaluated for approximately 60 days. Florfenicol and tilmicosin were administered as single SC injections according to labeled dosage. Tulathromycin was administered as a single SC injection of 2.5 mg/kg. In all three studies, the cure rate of calves 60 days after treatment with tulathromycin was significantly higher (P < or = .05) than that of calves treated with florfenicol or tilmicosin. Suspected adverse reactions were not reported for any of the study drugs. Tulathromycin proved to be significantly more effective than either florfenicol or tilmicosin in the treatment of BRD in stocker calves.  相似文献   
184.
Freshwater research and management efforts could be greatly enhanced by a better understanding of the relationship between landscape-scale factors and water quality indicators. This is particularly true in urban areas, where land transformation impacts stream systems at a variety of scales. Despite advances in landscape quantification methods, several studies attempting to elucidate the relationship between land use/land cover (LULC) and water quality have resulted in mixed conclusions. However, these studies have largely relied on compositional landscape metrics. For urban and urbanizing watersheds in particular, the use of metrics that capture spatial pattern may further aid in distinguishing the effects of various urban growth patterns, as well as exploring the interplay between environmental and socioeconomic variables. However, to be truly useful for freshwater applications, pattern metrics must be optimized based on characteristic watershed properties and common water quality point sampling methods. Using a freely available LULC data set for the Santa Clara Basin, California, USA, we quantified landscape composition and configuration for subwatershed areas upstream of individual sampling sites, reducing the number of metrics based on: (1) sensitivity to changes in extent and (2) redundancy, as determined by a multivariate factor analysis. The first two factors, interpreted as (1) patch density and distribution and (2) patch shape and landscape subdivision, explained approximately 85% of the variation in the data set, and are highly reflective of the heterogeneous urban development pattern found in the study area. Although offering slightly less explanatory power, compositional metrics can provide important contextual information.  相似文献   
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This study presents the morphology of the ovary, as well as the dynamics of the vitellogenesis process in oocytes of the cattle-tick Boophilus microplus. The ovary of these individuals is of the panoistic type; therefore, it lacks nurse cells. This organ consists of a single tubular structure, continuous, and composed of a lumen delimitated by a wall of small epithelial cells with rounded nuclei. In this tick species, the oocytes were classified into six stages varying from I to VI and according to: cytoplasm appearance and presence of the germ vesicle, yolk granules, and chorion. Oocytes of various sizes and at different developmental stages remain attached to the ovary through a cellular pedicel until completing stage V. Afterwards, they are liberated into the lumen and from there to the exterior. Some oocytes (classified as type VI) showed an atypical appearance indicating that some of the cellular components would be undergoing a degenerative process and/or reabsorption.  相似文献   
189.
OBJECTIVE: To describe and evaluate subtotal ostectomy of dorsal spinous processes (DSP) performed in standing horses. STUDY DESIGN: Retrospective study. SAMPLE POPULATION: Nine adult horses. METHODS: The diseased portions of the DSP were removed with the horses standing and sedated after infiltrating a local anesthetic agent around the affected DSP. Medical records of affected horses were reviewed to determine history, findings of physical and radiographic examination, surgical technique, postoperative complications, and outcome. RESULTS: Five horses had subtotal ostectomy of DSP because of osteomyelitis, and 4 because of impingement and/or fracture of DSP. Affected portions of DSP were removed safely and effectively, with no apparent discomfort to the horses; hemorrhage was minimal. CONCLUSIONS: Subtotal ostectomy of DSP can be performed safely in standing, conscious horses and the risks associated with general anesthesia are eliminated. Hemorrhage is minimal compared to that which occurs when the procedure is performed with horses anesthetized and in lateral recumbency. CLINICAL RELEVANCE: Access and visibility are better when subtotal ostectomy of the DSP is performed with the horse standing rather than anesthetized and in lateral recumbency. Performing subtotal ostectomy of diseased DSP with the horse standing avoids the expense and risks of general anesthesia.  相似文献   
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