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101.
S. Clare F.A. Hartmann M. Jooss E. Bachar Y.Y. Wong L.A. Trepanier K.R. Viviano 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(3):818-826
Background
Long‐duration beta‐lactam antibiotics are used for empirical treatment in female dogs with uncomplicated bacterial cystitis. However, women with bacterial cystitis are treated with short‐duration potentiated sulfonamides because longer courses of beta‐lactams result in lower cure and higher recurrence rates.Hypothesis/Objectives
Short‐duration potentiated sulfonamide treatment is more efficacious than long‐duration beta‐lactam treatment in achieving clinical and microbiological cures in female dogs with uncomplicated bacterial cystitis.Animals
Thirty‐eight client‐owned female dogs.Methods
Randomized, double‐blinded, placebo‐controlled clinical trial. Dogs were treated with TMP‐SMX (15 mg/kg PO q12h for 3 days followed by a placebo capsule PO q12h for 7 days; Group SDS; n = 20) or cephalexin (20 mg/kg PO q12h for 10 days; Group LDBL; n = 18). Dogs were monitored for clinical and microbiological cure during treatment and at short‐ and long‐term follow‐up.Results
No statistically significant differences were found between treatment groups in clinical cure rates after 3 days of treatment (89% SDS, 94% LDBL; P = 1.00) and 4 days (85% SDS, 72% LDBL; P = .44) or >30 days (50% SDS, 65% LDBL; P = .50) after conclusion of treatment or in microbiological cure rates 4 days (59% SDS, 36% LDBL; P = .44) or >30 days (44% SDS, 20% LDBL; P = .40) after conclusion of treatment.Conclusions and Clinical Importance
We did not identify a difference in cure rates between short‐duration sulfonamide and long‐duration beta‐lactam treatments in female dogs with uncomplicated cystitis. Long‐term cure rates in both treatment groups were low. In some female dogs, “uncomplicated” bacterial cystitis may be more complicated than previously recognized. 相似文献102.
S. Unterer K. Busch M. Leipig W. Hermanns G. Wolf R.K. Straubinger R.S. Mueller K. Hartmann 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2014,28(1):52-58
Background
Etiology of hemorrhagic gastroenteritis (HGE) syndrome in dogs is unknown and histopathologic and microbial investigations have only been performed post mortem.Objective
To identify characteristic intra vitam endoscopic and histologic mucosal lesions, as well as bacterial species, within the mucosa of dogs with HGE.Animals
Ten dogs diagnosed with HGE were included. Eleven dogs with gastroduodenoscopy and different intestinal diseases were used as controls for microbial changes. Dogs pretreated with antibiotics or diagnosed with any disease known to cause bloody diarrhea were excluded from the study.Methods
In this prospective study, gastrointestinal biopsies were collected from 10 dogs with HGE. Endoscopic and histologic changes were assessed according to WSAVA guidelines. Biopsies from the stomach, duodenum, ileum, and colon were investigated by histology and by immunohistochemistry for the presence of Clostridium spp. and parvovirus. The first duodenal biopsy taken with a sterile forceps was submitted for bacterial culture.Results
Acute mucosal lesions were only found in the intestines, not in the stomach. Clostridium spp., identified as Clostridium perfringens in 6/9 cases, were detected on the small intestinal mucosa in all dogs with HGE, either by culture or immunohistopathology. In the control group, C. perfringens could only be cultured in one of 11 dogs.Conclusions and Clinical Importance
The results of this study demonstrate an apparent association between C. perfringens and the occurrence of acute hemorrhagic diarrhea. The term “HGE,” which implies the involvement of the stomach, should be renamed as “acute hemorrhagic diarrhea syndrome.” 相似文献103.
Prevalence of antibodies against feline panleukopenia virus in client-owned cats in Southern Germany
Katherina Mende Bianca Stuetzer Carola Sauter-Louis Timo Homeier Uwe Truyen Katrin Hartmann 《Veterinary journal (London, England : 1997)》2014,199(3):419-423
Feline panleukopenia is a frequent and commonly fatal disease of cats. Recent published studies have raised suspicions that some cats fail to develop antibodies after vaccination. The purpose of this study was to assess the prevalence of antibodies against feline panleukopenia virus (FPV) in cats in Southern Germany, and to identify factors that are associated with a lack of antibodies. In total, 350 cats presented to the Clinic of Small Animal Medicine, Ludwig-Maximilians-Universitaet were randomly included in the study. Information regarding signalment, origin, environment, lifestyle, housing conditions, health status, chronic diseases, glucocorticoid therapy, and vaccination status were collected. Antibodies were detected by haemagglutination inhibition test. Asymptomatic chi-squared tests and univariable logistic regression were used to investigate associations between a lack of antibodies and the different variables. Associations determined to be statistically significant at P < 0.1 were verified by a multivariable logistic regression analysis.Of the 350 cats, 103 (29.4%) had no antibodies against FPV. Chronic kidney disease, neoplasia, glucocorticoid therapy, and vaccination status were significantly associated with a lack of antibodies. The cats with no antibodies were likely to have inadequate immunity against panleukopenia and those with chronic diseases or receiving glucocorticoids were less likely to be protected. 相似文献
104.
Cloud-radiative forcing and climate: results from the Earth radiation budget experiment 总被引:10,自引:0,他引:10
Ramanathan V Cess RD Harrison EF Minnis P Barkstrom BR Ahmad E Hartmann D 《Science (New York, N.Y.)》1989,243(4887):57-63
The study of climate and climate change is hindered by a lack of information on the effect of clouds on the radiation balance of the earth, referred to as the cloud-radiative forcing. Quantitative estimates of the global distributions of cloud-radiative forcing have been obtained from the spaceborne Earth Radiation Budget Experiment (ERBE) launched in 1984. For the April 1985 period, the global shortwave cloud forcing [-44.5 watts per square meter (W/m(2))] due to the enhancement of planetary albedo, exceeded in magnitude the longwave cloud forcing (31.3 W/m(2)) resulting from the greenhouse effect of clouds. Thus, clouds had a net cooling effect on the earth. This cooling effect is large over the mid-and high-latitude oceans, with values reaching -100 W/m(2). The monthly averaged longwave cloud forcing reached maximum values of 50 to 100 W/m(2) over the convectively disturbed regions of the tropics. However, this heating effect is nearly canceled by a correspondingly large negative shortwave cloud forcing, which indicates the delicately balanced state of the tropics. The size of the observed net cloud forcing is about four times as large as the expected value of radiative forcing from a doubling of CO(2). The shortwave and longwave components of cloud forcing are about ten times as large as those for a CO(2) doubling. Hence, small changes in the cloud-radiative forcing fields can play a significant role as a climate feedback mechanism. For example, during past glaciations a migration toward the equator of the field of strong, negative cloud-radiative forcing, in response to a similar migration of cooler waters, could have significantly amplified oceanic cooling and continental glaciation. 相似文献
105.
Sickafus KE Minervini L Grimes RW Valdez JA Ishimaru M Li F McClellan KJ Hartmann T 《Science (New York, N.Y.)》2000,289(5480):748-751
The radiation performance of a variety of complex oxides is predicted on the basis of a material's propensity to accommodate lattice point defects. The calculations indicate that a particular class of oxides possessing the fluorite crystal structure should accept radiation-induced defects into their lattices far more readily than a structurally similar class of oxides based on the pyrochlore crystal structure. Preliminary radiation damage experiments substantiate the prediction that fluorites are inherently more radiation resistant than pyrochlores. These results may permit the chemical durability and radiation tolerance of potential hosts for actinides and radioactive wastes to be tailored. 相似文献
106.
Derekas A Kiss LL Borkovits T Huber D Lehmann H Southworth J Bedding TR Balam D Hartmann M Hrudkova M Ireland MJ Kovács J Mezo G Moór A Niemczura E Sarty GE Szabó GM Szabó R Telting JH Tkachenko A Uytterhoeven K Benko JM Bryson ST Maestro V Simon AE Stello D Schaefer G Aerts C ten Brummelaar TA De Cat P McAlister HA Maceroni C Mérand A Still M Sturmann J Sturmann L Turner N Tuthill PG Christensen-Dalsgaard J Gilliland RL Kjeldsen H Quintana EV Tenenbaum P Twicken JD 《Science (New York, N.Y.)》2011,332(6026):216-218
Hierarchical triple systems comprise a close binary and a more distant component. They are important for testing theories of star formation and of stellar evolution in the presence of nearby companions. We obtained 218 days of Kepler photometry of HD 181068 (magnitude of 7.1), supplemented by ground-based spectroscopy and interferometry, which show it to be a hierarchical triple with two types of mutual eclipses. The primary is a red giant that is in a 45-day orbit with a pair of red dwarfs in a close 0.9-day orbit. The red giant shows evidence for tidally induced oscillations that are driven by the orbital motion of the close pair. HD 181068 is an ideal target for studies of dynamical evolution and testing tidal friction theories in hierarchical triple systems. 相似文献
107.
108.
A simplified parametric model to describe the magnitude and geometry of soil shrinkage 总被引:2,自引:0,他引:2
W. M. Cornelis J. Corluy H. Medina R. Hartmann M. Van Meirvenne & M. E. Ruiz 《European Journal of Soil Science》2006,57(2):258-268
Assessing the magnitude and geometry of soil shrinkage is indispensable for sound use and management of swelling and shrinking soils for agriculture and engineering. We have explored a simplified parametric model for the soil shrinkage characteristic curve, which is a measure for the magnitude of soil shrinkage, and tested it against experimental data for a Vertisol and a Lixisol under sugar cane in the Havana province, Cuba. We then applied the model to determine soil consistency limits, including the shrinkage, plastic and structural limits, using the model's third and fourth derivative. We further demonstrated how the model can be used to assess the geometry of shrinkage in terms of the relative crack area and the relative surface subsidence. Excellent matches were obtained between the observations and the fitted model. The shrinkage and structural limits corresponded to distinct changes in the soil shrinkage characteristic curve and were as such considered to be correctly estimated. The accuracy of the estimated plastic limit could, however, not been verified, since data were lacking. Linear regressions with R2 > 0.88 were established relating the shrinkage and plastic limits to the soil's COLE index and the cation exchange capacity. The model could be easily applied to determine the crack area and the surface subsidence. We finally demonstrated how a geometry factor rs plays a crucial role in determining the shrinkage geometry, particularly for rs values ranging from 1 to 3. 相似文献
109.
Schwarz K Huang SW German JB Tiersch B Hartmann J Frankel EN 《Journal of agricultural and food chemistry》2000,48(10):4874-4882
The activity of alpha-tocopherol, Trolox, propyl gallate, gallic acid, methyl carnosoate, and carnosic acid was studied in two oil-in-water (o/w) emulsions, in two water-in-oil (w/o) emulsions, and in bulk oil with and without added emulsifiers. All antioxidants had either moderate or higher activity in bulk oil than in the emulsions. In most emulsions, the most polar antioxidants, propyl gallate and gallic acid, exhibited either prooxidant activity or no antioxidant activity. Methyl carnosoate was the most active antioxidant in w/o emulsions but was less active than Trolox in o/w emulsions. alpha-Tocopherol was less active in bulk oil than in emulsions, but its activity in bulk oil was markedly enhanced by the addition of o/w emulsifiers. Partitioning of antioxidants, hydrogen bonding, interphase transport, surface accessibility, and interaction of emulsifier with antioxidants are considered to be important parameters that determine antioxidant activity in lipid-containing systems. 相似文献
110.
The presence of tryptophan in soil and auxin production by indigenous soil microbes are considered to be important natural plant growth-promoting factors. In order to elucidate the natural regulation of microbial auxin synthesis, we treated different soils by an air drying/rewetting cycle and measured pool sizes of auxins, auxin precursors, and degradation products of tryptophan together with a range of respiration parameters. Potential (tryptophan addition) microbial production of indole-3-acetic acid (auxin) was predominant in the equilibrated fresh soils. Auxin production depended on the soil nutrient content, and the size and metabolic status of the microbial biomass. Immediately after rewetting, potential auxin production was low, whereas potential indole-3-ethanol and anthranilic acid production as well as basal respiration were transitionally enhanced. This was concurrent with proliferation ofr-strategist microbes. After the respiration flush, the natural tryptophan contents increased, indicating cell lysis, probably caused by a rise in protozoan grazing on ther-strategists. Auxin production was high in fresh and in re-equilibrating rewetted soils, probably due to nutritional limitations under stationary conditions. Hence, this high production was attributed to theK-strategist component of the soil microflora. The differences observed in the recovery of auxin production between the different rewetted soils suggest that original activities can become re-established rapidly when the indigenous microbial community is pre-adapted to the stress. We propose that the release of tryptophan, microbial auxin, and the shift towards indole-3-ethanol production function as stimulants for root development induced by environmental fluctuations. 相似文献