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排序方式: 共有1214条查询结果,搜索用时 15 毫秒
1.
G R Johnston P A Walter D A Feeney 《Veterinary Clinics of North America: Small Animal Practice》1986,16(2):261-292
Radiopaque uroliths and nonradiopaque (water density) uroliths are filling defects encountered in the urinary tracts of dogs and cats. Other free luminal and attached soft tissue density filling defects encountered during uroradiographic special procedures include blood clots, air bubbles, hematomas, granulomas, abscesses, inflammatory and neoplastic polyps. Nonradiopaque uroliths cannot be identified on survey radiographs from other soft tissue dense structures. Gray scale ultrasonography can be used to differentiate nonradiopaque (water dense) uroliths from other soft tissue attached or free luminal filling defects of the excretory pathway. The differential radiographic features of filling defects encountered during cystography and urethrography are described and illustrated. 相似文献
2.
Ariana M.P. Nap Yvonne W.E.A. Pollak Walter E. van den Brom Ad Rijnberk DVM PhD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1994,8(4):302-303
Thyroidal 99m TcO4 (pertechnetate) uptake percentages were determined in unanesthetized euthyroid (n = 13) and hyperthyroid (n = 18) cats. Maximal uptakes were observed 60 minutes after IV injection of the radionuclide and ranged from 0.3 to 3.9% of the dose in euthyroid cats (median 2.23%) and from 5.2% to 23.9% of the dose in hyperthyroid cats (median 14.8%) ( P < .05). There were no overlaps in pertechnetate uptake percentages during any of the intervals evaluated. It is concluded that the optimal time for visualization of the thyroid by 99m TcO4 -scanning is 60 minutes after IV injection of the radionuclide. Calculation of the percentage uptake is of additional diagnostic value. 相似文献
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4.
Amin A. Nomeir Nicolas P. Hajjar Ernest Hodgson Walter C. Dauterman 《Pesticide biochemistry and physiology》1980,13(2):112-120
EPN is twice as toxic as EPNO to house flies from both the Diazinon-resistant strain and the susceptible strain. EPN and EPNO are also eight times more toxic to the susceptible than the resistant strain. This is due to the ability of the resistant strain to metabolize these compounds to a greater extent. Metabolism by the glutathione S-transferases present in the 100,000g supernatant is more extensive than that by the NADPH-dependent microsomal mixed-function oxidases. The glutathione S-transferases are the major route of metabolism for EPN and appear to be the principal mechanism conferring resistance. EPN was metabolized by the microsomal fraction via oxidative desulfuration to the oxygen analog, EPNO, and by oxidative dearylation to p-nitrophenol. EPNO was metabolized by the same system to p-nitrophenol and desethyl EPNO as well as to an unknown metabolite. The soluble fraction metabolized EPN to p-nitrophenol, S-(p-nitrophenyl)glutathione, O-ethyl phenylphosphonothioic acid, and S-(O-ethyl phenylphosphonothionyl)glutathione. The identification of the latter conjugate demonstrates a new type of metabolite of organophosphorus compounds. EPNO was metabolized by the soluble fraction to p-nitrophenol and S-(p-nitrophenyl)glutathione. 相似文献
5.
According to clinical studies, degenerative diseases of canine joints lead to higher lactate dehydrogenase (LDH) levels in synovial fluid. The goal of the present study was to examine the intraarticular distribution of LDH in healthy and osteoarthrotic knee joints in order to identify possible sources of LDH in synovial fluid. As synovial LDH concentrations neither correlate with the number of leukocytes nor with synovitis, our investigation focused on the articular cartilage. Samples from healthy and osteoarthrotic knee joints were fixed and processed for transmission electron microscopy (TEM), immunohistochemistry (IHC), and immunocytochemistry (ICC). In addition, fresh cartilage samples were investigated cytochemically by the tetrazolium‐formazan reaction. Analyses of blood and synovial fluid samples were used to confirm the absence of inflammatory disease. Morphology of articular cartilage was assessed macroscopically and by means of TEM. IHC revealed highest levels of LDH in chondrones and a diffuse labelling of the matrix with a distinctive decrease in signal from superficial to deeper cartilage layers. Ultrastructural localization by ICC showed LDH to be present in the cytoplasm of all chondrocytes and confirmed the density gradient in the matrix. Labelling was absent from nuclei and from pericellular rims. Cytochemistry confirmed the distribution pattern and, thus, expanded our findings beyond immunological evidence by providing proof of enzymatic activity of LDH in articular cartilage. The present results indicate that LDH is transferred from chondrocytes to the cartilaginous matrix. We suggest, therefore, that LDH found in synovial fluid originates from the articular cartilage and that osteoarthrotic processes promote LDH release from the cartilaginous matrix. 相似文献
6.
Lena Stiefvatter Konstantin Frick Katja Lehnert Walter Vetter Alexander Montoya-Arroyo Jan Frank Ulrike Schmid-Staiger Stephan C. Bischoff 《Marine drugs》2022,20(11)
Dietary supplements that promote healthy aging are mostly warranted in an aging society. Because of age-related risks, anti-inflammatory and anti-oxidative agents such as microalgae are potential candidates for intervention. In a randomized controlled trial, we tested Phaeodactylum tricornutum (PT), a microalgae rich in eicosapentaenoic acid (EPA), carotenoids, vitamins, and β-glucans, cultured in bioreactors. In this pilot trial, 19 healthy elderly received supplements for two weeks based on either the whole PT (A), the β-1,3-glucan-rich PT supernatant (SupB), the combination thereof (A+SupB), or a Comparator product (Comp). The primary outcome variable plasma interleukin-6 was reduced after treatment with A+SupB compared to the Comp group (p = 0.04). The mobility parameters 5 s sit-to-stand test (p = 0.04 in the A group) and by trend gait speed (p = 0.08 in the A+SupB diet) were improved compared to Comp. No treatment effects were observed for fatty acids, compared to Comp but omega-6 to -3 fatty acid ratio (p = 0.006) and arachidonic acid/EPA ratio (p = 0.006) were reduced within group A+SupB. Further, the SupB study product reduced faecal zonulin (p = 0.03) compared to the Comp. The data revealed an anti-inflammatory and potentially anti-oxidative effect of particular PT preparations, suggesting that they might be suitable for effects in healthy elderly. 相似文献
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8.
Soybean molasses as an organic carbon source in the farming of Litopenaeus vannamei (Boone, 1931) in a biofloc system 下载免费PDF全文
Carlos Manoel do Espírito Santo Isabela Claudiana Pinheiro Gabriel Fernandes Alves de Jesus José Luiz Pedreira Mouriño Felipe do Nascimento Vieira Walter Quadros Seiffert 《Aquaculture Research》2017,48(4):1827-1835
Soybean molasses was evaluated as a partial replacement for sugarcane molasses as a carbon source for biofloc development in the superintensive culture of Pacific white shrimp (Litopenaeus vannamei). A 50‐day study was conducted with juvenile (3.2 g) shrimp stocked in 16 800 L tanks at a stocking density of 250 shrimp m?3. Control of total ammonia concentration was performed by the addition of combined mixtures of soybean and sugarcane molasses to the culture water. Three different molasses treatments were evaluated using different soybean‐to‐sugarcane molasses ratios: 15–85%, 38–62% and 60–40% respectively. The control group was treated only with sugarcane molasses. Water quality, chlorophyll a concentration, heterotrophic bacterial load, Vibrio spp. concentration and zootechnical indexes were all evaluated. Total ammonia concentration was controlled by heterotrophic and chemotrophic pathways. Biofloc formation, as quantified by measuring the total suspended solids, was not altered. The Vibrio spp. concentration showed a significant reduction in treatments with soybean‐to‐sugarcane molasses ratios of 38–62% and 60–40%. All combined mixtures of soybean and sugarcane molasses could maintain water quality and productivity in the superintensive culture of L. vannamei using the biofloc system. Thus, the potential use of a residue from agroindustry as a carbon source in a biofloc culture is demonstrated. 相似文献
9.
Walter Thalenhorst 《Journal of pest science》1938,14(9):105-109
Ohne Zusammenfassung
Mit 2 Abbildungen. 相似文献
10.
Billy P. R. Dries Ilse Jonkers Wim Van Den Broeck Benedicte Vanwanseele Lieve DeRycke Walter Dingemanse Jos Vander Sloten Henri Van Bree Ingrid Gielen 《Anatomia, histologia, embryologia》2021,50(3):637-644
In contrast to other mammals, the large variation in dog sizes is not accompanied by any significant genetic re-organization. In order to study the relationship between body mass, limb length and the functional anatomical muscle parameters of the canine hind limb, a large dataset comprising of muscle masses, optimal muscle fibre lengths and physiological cross-sectional area's (PCSA) were acquired for twenty-five muscles in ten dogs of sizes varying between 20 kg and 52 kg. The potential of body mass and limb length for reliably scaling individual muscle masses, optimal muscle fibre lengths and PCSA's were examined. For the majority of the muscles of the canine hind limb, neither body mass nor limb length were reliable scaling parameter for either muscle masses, PCSA's and optimal fibre length. These results indicate the need of a breed-specific approach to musculoskeletal modelling in future canine musculoskeletal research. 相似文献