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31.
Nine cats, from 11 to 17 years of age (mean 13.6 years of age), were diagnosed with a cranial mediastinal cyst. Thoracic radiographs in all cats were characterized by an increased soft tissue opacity in the cranial mediastinum confirmed to be a cyst by ultrasonography or necropsy. Ultrasonographically cysts appeared as an anechoic mass. A low-cellularity clear fluid was obtained on aspiration. The majority of the cats (n = 8) presented for unrelated conditions with no signs of respiratory distress. No treatment for the cyst was pursued except for drainage during ultrasonographic-guided aspiration in several cats. On follow-up of eight cats, none were symptomatic for the cyst from 3-45 months after diagnosis. Mediastinal cyst should be considered when a cranial mediastinal mass is evident radiographically in an older cat. The majority of feline cranial mediastinal cysts are benign with no need for treatment. 相似文献
32.
Digestion rates were determined for natural prey items offered to each of seven species of sea anemones found at Wooley’s Pool in False Bay and to the single species (Bunodactis reynaudi) recorded at Biouberg on the Atlantic coast of the south-western Cape, South Africa.This was done by examining prey items removed from the coelenterons at regular intervals after feeding and assessing their degree of digestion according to a predetermined scale. There was considerable variation in the gut retention times between different anemone species offered the same prey types, with Actinia equina consistently showing the shortest gut retention times (12 h for amphipods, 15 h for pelecypods and 23 h for isopods). Of the various prey categories tested, amphipods tended to be the most rapidly digested group, while molluscs and echinoderms usually remained in the coelenteron the longest. Mean gut retention times in B. reynaudi, the only species found both in False Bay (17°C) and on the cold west coast (12°C) were markedly longer (72 vs 60 h and 43 vs 30 h for pelecypods and gastropods respectively) at the lower temperature. 相似文献
33.
Land-use and vegetation cover have been linked to the nutrient levels (nitrogen, phosphorus) of surface waters in several
countries. However, the links generally relate to streams and rivers, or to specific types of standing water, for example
shallow lakes in a geologically defined region. We measured physical variables and nutrient chemistry of 45 water bodies representative
of the wide range of lentic wetland environments (swamps, riverine wetlands, estuaries, reservoirs, shallow lakes, deep lakes)
in Otago, New Zealand, and related these to catchment variables and land-use in order to assess the potential influence of
catchment modification on water quality of these diverse wetlands. Catchment boundaries and land cover were derived from maps
using ArcView GIS software. Our predictions that concentrations of nutrients and other components of water quality would correlate
positively with the nature and intensity of catchment modification were confirmed in multivariate analyses. Physical and chemical
measures were positively related to the extent of modification in the catchment (percentage of the catchment in pasture, planted
forest, scrub and urban areas), and negatively related to lack of catchment modification (more of the catchment in bare ground,
tussock grassland and indigenous forest). The strong negative correlations between nutrient concentrations, suspended sediment,
water colour and the percentage of tussock cover in the catchment imply that increased conversion of the␣native tussock grassland
to pastoral farming in␣Otago will increase nutrient concentrations and␣reduce water quality of the diverse lentic ecosystems. 相似文献
34.
Lisa J. Thompson DVM ; Ravi Seshadri DVM DACVECC DAVBP Marc R. Raffe DVM MS DACVA DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(2):165-173
Objective – Describe clinical characteristics and outcomes associated with canine patients undergoing surgical intervention for treatment of acute pancreatitis.
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis. 相似文献
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis. 相似文献
35.
Christiana M. Glover Lisa M. Miller Noel O. Dybdal Alfonso Lopez Wendy M. Duckett Dianne McFarlane 《Journal of Equine Veterinary Science》2009
The objective of this study was to describe the histopathologic changes observed in extrapituitary organs as well as the pituitary glands of horses with pituitary pars intermedia dysfunction (PPID). Adrenal gland, thyroid gland, liver, lung, kidney, heart, and pituitary gland from 32 horses with clinical and histologic evidence of PPID and 20 control horses were reviewed histologically. Ten of the control horses were aged animals (≥15 years), allowing those changes attributed to age to be identified. In addition to previously reported changes in adrenal gland and liver, an association was established between PPID and several extrapituitary histopathologic changes, namely bronchiolitis, proliferative glomerulopathy, and myocardial lipofuscinosis and fibrosis. The potential biologic significance of these changes is discussed and, although the retrospective design of the current study precludes establishment of causal relationships between the observed extrapituitary changes and PPID, these findings suggest that further investigations are warranted. 相似文献
36.
Albasan H Lulich JP Osborne CA Lekcharoensuk C Ulrich LK Carpenter KA 《Journal of the American Veterinary Medical Association》2003,222(2):176-179
OBJECTIVE: To determine effects of storage temperature and time on pH and specific gravity of and number and size of crystals in urine samples from dogs and cats. DESIGN: Randomized complete block design. ANIMALS: 31 dogs and 8 cats. PROCEDURE: Aliquots of each urine sample were analyzed within 60 minutes of collection or after storage at room or refrigeration temperatures (20 vs 6 degrees C [68 vs 43 degrees F]) for 6 or 24 hours. RESULTS: Crystals formed in samples from 11 of 39 (28%) animals. Calcium oxalate (CaOx) crystals formed in vitro in samples from 1 cat and 8 dogs. Magnesium ammonium phosphate (MAP) crystals formed in vitro in samples from 2 dogs. Compared with aliquots stored at room temperature, refrigeration increased the number and size of crystals that formed in vitro; however, the increase in number and size of MAP crystals in stored urine samples was not significant. Increased storage time and decreased storage temperature were associated with a significant increase in number of CaOx crystals formed. Greater numbers of crystals formed in urine aliquots stored for 24 hours than in aliquots stored for 6 hours. Storage time and temperature did not have a significant effect on pH or specific gravity. CONCLUSIONS AND CLINICAL RELEVANCE: Urine samples should be analyzed within 60 minutes of collection to minimize temperature- and time-dependent effects on in vitro crystal formation. Presence of crystals observed in stored samples should be validated by reevaluation of fresh urine. 相似文献
37.
Waldrop JE Rozanski EA Freeman LM Rush JE 《Journal of the American Animal Hospital Association》2003,39(6):523-527
Fifty-five dogs received packed red blood cell (PRBC) transfusions for gastrointestinal (GI) hemorrhage during a 26-month period (1999 to 2001), accounting for 11.7% of the PRBC transfusions in that time. Thirty-nine (61%) dogs had an intestinal pathology (primary or secondary) as the cause of GI hemorrhage, including intestinal masses, gastroenteritis, hepatic disease, and renal disease. Nonsteroidal and steroidal anti-inflammatory drug use was found frequently in dogs with GI hemorrhage. Sixteen (39%) dogs were identified as having immune-mediated thrombocytopenia (IMT) and associated GI hemorrhage. Dogs with IMT received more transfusions of PRBC than nonIMT dogs (P<0.03) and received a significantly larger total volume of PRBC (P<0.01) during hospitalization. 相似文献
38.
A significant challenge facing forestry today is managing private forests sustainably in the face of continued ownership fragmentation
(i.e., parcelization). Cross-boundary coordination––where forest practices are coordinated across multiple properties––has
been proposed as a mechanism by which landscape-level ecological and economic benefits may be accrued in privately-owned landscapes,
but few tests of the concept exist. Using a case study approach, we quantify the extent to which ownership-centric forest
management is constrained by economies of scale and misses opportunities to achieve ecological objectives in three landscapes
in Wisconsin, USA. Methods are based on existing forest management plans and include spatial analysis of patch distributions
and shapes, simulation of forest practices, and calculation of net present value over a 20-year horizon. Our results indicate
substantial opportunity for cross-boundary coordination: between 62% and 88% of the managed properties within our study landscapes
were adjacent to other properties with forest management plans. At a patch scale, coordination can result in ecological benefits
that can be accrued into the future (e.g., maintenance of large patches and natural ecosystem boundaries). Because these landscapes
are already highly parcelized, however, coordination offers little opportunity to impact the overall landscape-scale structure.
Greater economies of scale can also be gained by coordinating forest practices, including increases in the size (16–99%) and
volume of timber sales (16–94%), and a modest economic advantage (3–6%). As first steps, investment in data infrastructure
and professional training are required to support cross-boundary multi-ownership forest management. More broadly is the need
to shift from policies and practices that are largely ownership-centric to those that include and better incorporate landscape-centric
perspectives. 相似文献
39.
40.
Jan Fahleson Ulf Lagercrantz Qiong Hu Lisa Ann Steventon Christina Dixelius 《European journal of plant pathology / European Foundation for Plant Pathology》2003,109(4):361-371
Amplified fragment length polymorphism (AFLP) analysis was used to study genetic variation among 76 isolates of Verticillium. A dendrogram based on the AFLP data revealed three main groups. One group consisted of 35 European isolates derived from Brassica napus together with five Californian isolates taken from B. oleracea. This group displayed a high degree of genetic similarity and included three isolates earlier classified as Verticillium longisporum, indicating that all isolates in this group probably should be regarded as members of V. longisporum. V. dahliae isolates constituted the second group while the third group contained four V. albo-atrum isolates. In addition to these three groups, a cluster of six V. nigrescens isolates was observed. However, the genetic distances between the isolates of V. nigrescens were much higher than those between members in the other groups and the bootstrap value for the V. nigrescens cluster was subsequently low. Four isolates classified as V. tricorpus were highly diverse and did not cluster together. Analysis of molecular variance revealed that the isolates of V. longisporum were separated into four subgroups, based on geographic origin. The study furthermore shows that AFLP is a suitable method for studying population structure in Verticillium. 相似文献