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排序方式: 共有229条查询结果,搜索用时 15 毫秒
31.
CAROLINA I. URRACA DEL JUNCO TIM S. MAIR SARAH E. POWELL PETER I. MILNER ALEX F. FONT TOBIAS SCHWARZ MARTIN P. WEAVER 《Veterinary radiology & ultrasound》2012,53(1):71-75
The magnetic resonance (MR) imaging features, signalment, clinical history and outcome of 55 horses with a penetrating sole injury were evaluated. Our aim was to describe MR imaging findings within the hoof capsule, assess the utility of the technique and give recommendations for the optimal MR imaging protocol to evaluate such injuries. Data from five equine hospitals were analyzed retrospectively. The tract was more likely to be visualized in animals scanned within the first week postinjury. There was no significant predisposition based on breed, age, or gender. T2*W transverse sequences were the most useful for assessment of solar penetrations due to their orientation perpendicular to the deep digital flexor tendon, the reduced scanning time, and the T2* capability of enhancing magnetic susceptibility caused by hemorrhage. 相似文献
32.
In humans, the empty sella is defined as herniation of the subarachnoidal space into the sella turcica with invisible (total empty sella) or reduced (partial empty sella) hypophyseal size. An empty sella can be associated with endocrine disturbances. The purpose of this study was to determine if the empty sella exists in dogs or cats and whether it is associated with endocrinopathy or hydrocephalus. Archived magnetic resonance images of the head of 370 dogs and 77 cats were re-evaluated specifically for the presence or absence of the pituitary gland. Hypophyseal tissue filling more than 50% of the sella was considered normal, between 30% and 50% was defined as partial empty sella and less than 30% was defined as total empty sella. In patients with an empty sella, and in all other imaged dogs of the affected breeds, the ventricle to brain ratio was measured. In patients with an empty sella, the medical record was searched for evidence of endocrinopathy. No cat had an empty sella but 11 dogs (3%) had a small or missing hypophysis. Seven of these dogs had a ventricle to brain ratio greater than 15%. Only small dogs (mean weight of 6.7 kg) were affected. One dog with an empty sella had signs of central hyperadrenocorticism while the other 10 had no sign of endocrinopathy. We conclude that the empty sella exists in dogs but is not generally associated with endocrinopathy. 相似文献
33.
PC Sereno AL Beck DB Dutheil B Gado HCE Larsson GH Lyon JD Marcot OWM Rauhut RW Sadleir CA Sidor DD Varricchio GP Wilson JA Wilson 《Science (New York, N.Y.)》1998,282(5392):1298-1302
Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous. 相似文献
34.
RL Westemeier JD Brawn SA Simpson TL Esker RW Jansen JW Walk EL Kershner JL Bouzat KN Paige 《Science (New York, N.Y.)》1998,282(5394):1695-1698
Effects of small population size and reduced genetic variation on the viability of wild animal populations remain controversial. During a 35-year study of a remnant population of greater prairie chickens, population size decreased from 2000 individuals in 1962 to fewer than 50 by 1994. Concurrently, both fitness, as measured by fertility and hatching rates of eggs, and genetic diversity declined significantly. Conservation measures initiated in 1992 with translocations of birds from large, genetically diverse populations restored egg viability. Thus, sufficient genetic resources appear to be critical for maintaining populations of greater prairie chickens. 相似文献
35.
RW Davis LA Fuiman TM Williams SO Collier WP Hagey SB Kanatous S Kohin M Horning 《Science (New York, N.Y.)》1999,283(5404):993-996
The hunting behavior of a marine mammal was studied beneath the Antarctic fast ice with an animal-borne video system and data recorder. Weddell seals stalked large Antarctic cod and the smaller subice fish Pagothenia borchgrevinki, often with the under-ice surface for backlighting, which implies that vision is important for hunting. They approached to within centimeters of cod without startling the fish. Seals flushed P. borchgrevinki by blowing air into subice crevices or pursued them into the platelet ice. These observations highlight the broad range of insights that are possible with simultaneous recordings of video, audio, three-dimensional dive paths, and locomotor effort. 相似文献
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38.
R. NAGILLA D. D. DESHMUKH K. J. COPEDGE S. MILLER B. MARTIN E. C. BELL S. H. DURAN & W. R. RAVIS 《Journal of veterinary pharmacology and therapeutics》2009,32(1):49-55
The purpose of this study was to investigate the stereospecific pharmacokinetics of ketorolac (KT) in goats following a single 2 mg/kg intravenous (i.v.) dose and a single 6 mg/kg oral dose. A stereoselective high pressure liquid chromatography assay was used to quantify ketorolac plasma concentrations. Pharmacokinetic parameters for both stereoisomers were estimated by model independent methods. Following an i.v. dose, the plasma concentration profiles for the stereoisomers were similar with half-lives of 1.05 ± 0.62 h for R -KT and 1.05 ± 0.61 h for S -KT. Clearance values for R - and S -KT after an i.v. dose were 0.53 ± 0.23 and 0.54 ± 0.23 L·h/kg, respectively. Following an oral dose, the terminal half-lives were longer with values of 34.08 ± 11.81 and 33.97 ± 12.19 h for R -KT and S- KT, respectively. The average bioavailability was 133 ± 23% for R -KT and S -KT, respectively. The longer half-lives and high apparent bioavailability after oral dosing are suggestive of a slow absorption process in the gastrointestinal tract and recycling. The results indicate that interconversion of the stereoisomers of ketorolac is absent in goats. However, studies with individual isomers are needed before any conclusion can be drawn about the lack of bioinversion. 相似文献
39.
MIRIAM KLEITER KARSTEN VELDE EDMUND HAINISCH ULRIKE AUER MARTIN REIFINGER 《Veterinary radiology & ultrasound》2009,50(5):560-563
A 13-month-old Standardbred Colt had a recurrent hemangioma at the level of the coronary band. Multiple excisions had led to a nonhealing skin and hoof defect. Using 14 MV electrons, a total dose of 36 Gy was administered, given as six fractions of 6 Gy twice a week. Wound healing by second intention was achieved over the next 4 months and the colt began race training 6 months after the end of therapy. Twenty months later the colt is sound and there is no evidence of tumor recurrence. 相似文献
40.
MARTIN GUILLOT MARC-ANDRÉ D'ANJOU KATE ALEXANDER CHRISTIAN BÉDARD MICHEL DESNOYERS GUY BEAUREGARD JÉRÔME R. E. DEL CASTILLO 《Veterinary radiology & ultrasound》2009,50(5):513-518
While abdominal ultrasound and ultrasound-guided fine-needle aspiration cytology are often combined to help determine the type of liver disease in dogs, little is known about the relationship that may exist between the results of these tests. We hypothesized that specific sonographic findings, or combinations of findings, may predict results of liver ultrasound-guided fine-needle aspiration cytology. Hepatic and extrahepatic sonographic findings were recorded prospectively using a standardized form in 70 dogs with clinically suspected liver disease and in which liver ultrasound-guided fine-needle aspiration cytology was performed. The predictive value of sonographic findings in regard to the category of cytology results was assessed with stepwise logistic regression analysis. Sonographic detection of a hepatic mass (≥3 cm; risk ratio [RR] 3.83, 95% Wald confidence intervals [95% CI] 2.42–3.93, P =0.0036), ascites (RR 3.82, 95% CI 1.94–4.28, P =0.0044), abnormal hepatic lymph node(s) (RR 3.01, 95% CI 1.22–4.88, P =0.0262), and abnormal spleen (RR 3.26, 95% CI 1.20–3.85, P =0.0274) were the most predictive of liver neoplasia on cytology. Conversely, sonographic detection of hepatic nodules (<3 cm; RR 1.97, 95% CI 0.95–2.96, P =0.0666) was most predictive of vacuolar hepatopathy on cytology. In dogs with suspected liver disease, several sonographic findings, alone or combined, are thus predictive of liver ultrasound-guided fine-needle aspiration cytology results. In the light of the fact that ultrasound-guided fine-needle aspiration cytology of the liver has limitations, these predictabilities could influence the selection of diagnostic tests to reach a reliable diagnosis. 相似文献