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排序方式: 共有190条查询结果,搜索用时 15 毫秒
1.
SUSCEPTIBILITY ARTIFACTS ON T2*‐WEIGHTED MAGNETIC RESONANCE IMAGING OF THE CANINE AND FELINE SPINE 下载免费PDF全文
The T2*‐weighted gradient recalled echo sequence is a sensitive means to detect blood degradation products. While not a routine sequence in magnetic resonance imaging of the spine in small animals, it can provide additional valuable information in select cases. The goal of this retrospective, cross‐sectional study was to describe findings when acquiring this sequence during magnetic resonance imaging examination of the spine in small animals. The University of Tennessee's veterinary radiology database was searched for dogs and cats that underwent magnetic resonance imaging for suspect spinal disease in which a T2*‐weighted gradient recalled echo sequence was acquired and susceptibility artifact was identified. The following information was recorded: signalment, clinical signs, location and appearance of susceptibility artifact, and final diagnosis. Thirty‐nine cases were included in the study. Extradural susceptibility artifacts were observed in cases of intervertebral disc herniation with or without associated hemorrhage (n = 28), extradural hemorrhage associated with spinal trauma (n = 2), hemophilia (n = 1), and in a cystic extradural mass (n = 1). Remaining lesions displaying susceptibility artifact were intramedullary and included presumptive acute noncompressive nucleus pulposus extrusion (n = 2), hematoma (n = 1), hemangiosarcoma metastasis (n = 1), intramedullary disc extrusion (n = 1), presumptive meningomyelitis (n = 1), and a mass of undetermined etiology (n = 1). Inclusion of a T2*‐weighted gradient recalled echo sequence may be helpful in spinal magnetic resonance imaging when standard imaging sequences are ambiguous or intramedullary lesions are observed. 相似文献
2.
The paper examines the interactions between the demands of society, the restrictions due to recreational and protective functions
of forests and the intensity and kind of forest management in the various ownership classes in Switzerland (CH) and Baden–Württemberg
(BW) in south–west Germany. A survey was carried out among owners of communal forests, private forest landholders owning more
than 200 ha of forest land and small-scale forest enterprises with up to 200 ha of forest land. The survey adopted a two-dimensional
approach, using regions and comparable ownership classes in order to identify basic differences and underlying key drivers.
It became obvious that there are relevant distinctions between the two countries. The paper highlights the present use of
forests, the restrictions perceived by their owners, and the underlying management strategies in terms of structure of the
forests, tree species composition and thinning activities. In BW the financial function is the dominant motivation for the
majority of the private owners. The communities emphasize both timber and non-timber functions of their forests. Except for
the protection function (avalanches, rockslides) the utilisation and importance of the forest in CH is lower than in BW. Profitability
of forests continues to be a key-driver of intensity of forest management activities, but there is less influence on the choice
of basic silvicultural strategies. The results of this comparative survey are placed in the context of a forest policy framework
and the medium-term financial situation in the two countries.
相似文献
Christoph HartebrodtEmail: |
3.
Tetracyclines are widely used in farm animals. This can cause drug residues in products of animal origin and, after excretion of these substances, in animal slurry and in soil fertilized with that slurry. In this paper, we present a method based on a microbiological assay coupled with HPLC for the detection of oxytetracycline, tetracycline, and chlortetracycline in eggs. After a simple liquid extraction of the samples and HPLC separation, fractions were collected on microtiter plates, and the tetracyclines were analyzed using the Staphylococcus aureus assay. This method was able to identify residues of tetracyclines in eggs at a level set by regulatory agencies (i.e., 200 microg/kg). In addition, it was shown that the described microbiological method can be used as a screening assay for the detection of tetracyclines and possible biologically active metabolites in animal slurry and soil samples. Employing the same extraction procedure, it was demonstrated that LC-MS-MS allowed the quantification of 20-400 microg/kg in eggs with recoveries ranging from 71 to 109% and RSDs of 3-15%. 相似文献
4.
Silke Ruppel Vigdis Torsvik Frida Lise Daae Lise Øvreås Jörg Rühlmann 《Biology and Fertility of Soils》2007,43(4):449-459
In this study, the interrelation between nitrogen availability and prokaryotic diversity are studied using a well-characterised
system from a long-term field experiment on a loamy sandy soil. The prokaryotic potential functional diversity and community
composition were assessed using community-level physiological profiling (CLPP), and their phylogenetic diversity was analysed
using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) in combination with sequencing analysis.
Highest prokaryotic potential functional diversity was measured in the control soil receiving no N fertilisation, indicating
an efficient as well as versatile utilisation of the substrates in this soil. Both substrate utilisation richness and substrate
utilisation evenness, the two constituents of the functional diversity, were decreased with increasing N supply. Furthermore,
distinct prokaryotic community compositions were generated in N-enriched soils compared to unfertilised control soils. These
differences suggest a dominance of populations adapted to utilising readily available substrates. We demonstrated that the
shift in prokaryotic functional diversity was connected to a shift in the phylogenetic structure of the bacterial and archaeal
communities. Taken together, our data clearly show that, for the sandy soil system, prokaryotic diversity and N availability
were interrelated. 相似文献
5.
6.
DAVID A. HUNT DVM JACK R. SNYDER DVM PhD DiplomateACVs JOE P. MORGAN DVM Vet Med Dr DiplomateACVR JOHN R. PASCOE BVSC PhD 《Veterinary surgery : VS》1990,19(1):41-49
The medical records of 25 horses 1 year of age or younger affected with femoral head and neck fractures during an 18 year period were reviewed. Each fracture involved the capital physis. The foals were 11 days to 12 months of age (mean, 5 months). No femoral capital physeal fractures occurred in horses older than 1 year of age during the same period. The history in each case included acute onset of severe unilateral hindlimb lameness, 3 hours to 2 months (mean, 12 days) before presentation. Injuries observed were violent falls, struggles, and kicks. Crepitation, swelling, pain with manipulation or palpation or both, and apparent fracture fragment displacement were inconsistently noted. Tentative clinical diagnoses were confirmed by radiography in 24 foals and by necropsy alone in one foal. Twenty-one foals were euthanatized due to poor prognosis. One foal sent home for stall rest was lost to follow-up. Surgical repair was attempted in three foals. Two fractures were repaired with multiple intramedullary pins and the foals were euthanatized within 2 weeks due to surgical failure and, in one case, contralateral limb breakdown. The third fracture was repaired with a compressing screw and plate device; the animal was pasture sound at month 20. 相似文献
7.
Berkefeld H Sailer CA Bildl W Rohde V Thumfart JO Eble S Klugbauer N Reisinger E Bischofberger J Oliver D Knaus HG Schulte U Fakler B 《Science (New York, N.Y.)》2006,314(5799):615-620
Large-conductance calcium- and voltage-activated potassium channels (BKCa) are dually activated by membrane depolarization and elevation of cytosolic calcium ions (Ca2+). Under normal cellular conditions, BKCa channel activation requires Ca2+ concentrations that typically occur in close proximity to Ca2+ sources. We show that BKCa channels affinity-purified from rat brain are assembled into macromolecular complexes with the voltage-gated calcium channels Cav1.2 (L-type), Cav2.1 (P/Q-type), and Cav2.2 (N-type). Heterologously expressed BKCa-Cav complexes reconstitute a functional "Ca2+ nanodomain" where Ca2+ influx through the Cav channel activates BKCa in the physiological voltage range with submillisecond kinetics. Complex formation with distinct Cav channels enables BKCa-mediated membrane hyperpolarization that controls neuronal firing pattern and release of hormones and transmitters in the central nervous system. 相似文献
8.
The arthropod-borne Schmallenberg virus (SBV), family Orthobunyaviridae, emerged in Europe in 2011. SBV is associated with a mild disease in adult ruminants but fetal malformation after an infection during a critical phase of pregnancy. A number of inactivated vaccines have been developed; their efficacy after two injections was demonstrated. To make the vaccination of sheep more efficient and economic the effect of a single immunization with one of these vaccines was investigated in the present study. Five vaccinated sheep and five additional control sheep were inoculated with SBV three weeks after vaccination and the results of a competitive ELISA, a standard microneutralization test and an SBV-specific real-time RT-PCR confirmed vaccine efficacy by demonstrating complete inhibition of viral replication in immunized animals. 相似文献
9.
TAKAYOSHI MIYABAYASHI BVS MS JOE P. MORGAN DVM VET MED DR MATTHEW A. O. ATILOLA DVM MS LUKE MUHUMUZA DVM 《Veterinary radiology & ultrasound》1986,27(6):164-168
Gastric emptying time and small intestinal transit time in dogs are frequently discussed. However, it is often of interest to the radiologist to know what normal small intestinal emptying times should be. A total of 15 upper gastrointestinal studies was performed on five internal parasite-free, normal, standard Beagle dogs with three studies on each dog, 6 days apart. The ages and weights of the dogs ranged from 2–8 years and from 12.4–13.7 kg, respectively. Following 24-hour fasting, a dose of 10 ml/kg bw of 60% wt/vol barium sulfate suspension was administered through a stomach tube. Then, sequential radiographs were made at 30-minute intervals until the entire contrast medium column was in the colon and cecum. The mean, standard deviation, and range of gastric emptying time, small intestinal transit time, and small intestinal emptying time were 76 ± 16.7 (30–120), 73 ± 16.4 (30–120), and 214 ± 25.1 (180–300) minutes, respectively. This study offers the possibility that small intestinal emptying time may be used to further evaluate patients with suspected small intestinal partial obstruction, pseudo-obstruction, ischemia, or lymphangiectasia. 相似文献
10.
Scott A Rizzo Shelley J Newman Silke Hecht William B Thomas 《Journal of veterinary diagnostic investigation》2008,20(3):372-375
A 1.5-year-old castrated, male, mixed-breed dog was evaluated because of a 2-week history of lethargy, stiffness, and progressive paraparesis. Spinal radiographs, myelography, and computed tomography of the region showed a locally invasive mass involving the thoracic wall. Upon necropsy, an encapsulated, fluctuant mass was noted attached to the right dorsal body wall in the region of the fifth to seventh thoracic vertebra. Churukian-Schenk staining revealed positive granules within the neoplastic cell cytoplasm and immunohistochemistry was positive for expression for cytoplasmic neuron-specific enolase and synaptophysin. Chromogranin A and S100 expression were found to be negative. Immunohistochemistry and silver staining did not allow further differentiation of the tumor, and the diagnosis remains consistent with either a chromaffin paraganglioma or a nonchromaffin paraganglioma (chemodectoma) with some production of catecholamines. Extra-adrenal paragangliomas are rare neoplasms in dogs but should be considered as a possible differential diagnosis for a primary paraspinal thoracic mass. 相似文献