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61.
Three cheetahs (Acinonyx jubatus) had a clinical history of chronic spiral bacteria-associated gastritis and three cheetahs had no clinical history of gastritis. Gastric biopsies were obtained from all six cheetahs prior to treatment for gastritis and 3 wk and 1 yr posttreatment. The cheetahs were treated with tetracycline hydrochloride 500 mg p.o. q.i.d., metronidazole 250 mg p.o. q.i.d., and bismuth subsalicylate 300 mg p.o. q.i.d. Each drug was administered concurrently for 7 days. Following this treatment, each cheetah was maintained on 300 mg bismuth subsalicylate p.o. s.i.d. for 1 yr. The three cheetahs with a history of gastritis were culture positive for Helicobacter acinonyx and remained positive during the entire study. The three cheetahs with no clinical history of gastritis were culture negative for H. acinonyx, but gastric biopsies revealed Gastrospirillum-like bacteria (tentatively named Helicobacter heilmannii) pretreatment. Gastric biopsies were negative for H. heilmannii on subsequent examinations. Although the treatment did not eradicate H. acinonyx, it did provide symptomatic relief from the vomiting, anorexia, and weight loss associated with clinical gastritis. The use of endoscopically guided gastric mucosal biopsies for urease testing and histopathologic examination of Warthin-Starry-stained sections is a sensitive and specific method of diagnosing spiral bacteria-associated gastritis. Treatment of spiral bacteria-associated gastritis in cheetahs should include the rational use of antibiotics (tetracycline or amoxicillin and metronidazole), bismuth compounds, and omeprazole and evaluation of husbandry methods to reduce stress. 相似文献
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Hyunkyu Lee Pauline L. Baniqued Joshua Cosman Sean Mullen Edward McAuley Joan Severson Arthur F. Kramer 《Computers in human behavior》2012
Many studies conducted in a laboratory or university setting are limited by funding, personnel, space, and time constraints. In the present study, we introduce a method of data collection using a mobile application that circumvents these typical experiment administration issues. Using the application, we examined cross-sectional age differences in cognitive function. We obtained data from more than 15,000 participants and replicated specific patterns of age-related differences in cognition. Using a subset of these participants, we also examined the processing speed account of age-related cognitive differences, and the association of exercise and leisure activity with cognitive function across the lifespan. We discuss the relative advantages and disadvantages of data collection with a mobile application, and provide recommendations for the use of this method in research. 相似文献
64.
An analysis of the crystal structure of polytype 3R2 layered double hydroxides has been carried out based on XRPD diffractograms. Measurement of the transmission-XRPD pattern carried out in a spinning and tilting capillary using synchrotron radiation has been shown to diminish the preferred orientation effect of the sample. In order to approach the structure of polytype 3R2, structural models, based on possible interlayer anion arrangement as revealed by FT-IR, 27-Al solid state NMR and XRPD, were constructed. A structural model is proposed that is consistent with the by XRPD measured interlayer distance, in which tetrahedral aluminate ions are grafted with their apical oxygen ions onto the octahedral sheet. The presence of a measured extra reflection at 2θ value of 6.3, which is not predicted by this structure, can be obtained however by enlargement of the unit cell to a′ = a√3 = 0.5279 nm and c′ = c = 2.1985 nm, which simulates the aluminate anions ordering in the interlayer. 相似文献
65.
Silver-ion high-performance liquid chromatographic separation and identification of conjugated linoleic acid isomers 总被引:38,自引:21,他引:17
Najibullah Sehat Martin P. Yurawecz John A. G. Roach Magdi M. Mossoba John K. G. Kramer Youh Ku 《Lipids》1998,33(2):217-221
This is the first report of the application of silverion impregnated high-performance liquid chromatography (Ag+-HPLC) to the separation of complex mixtures of conjugated linolenic acid (CLA) isomers present in commercial CLA sources and foods and in biological specimens. This method showed a clear separation of CLA isomers into three groups related to their trans,trans, cis,trans or trans,cis, and cis,cis configuration of the conjugated double-bound system. In addition, this method separated within each geometrical isomeric group. Following Ag+-HPLC isolation, gas chromatography (GC)-electron impact mass spectrometry, and GC-direct deposition-Fourier transformed infrared spectroscopy were used to confirm the identity of two major positional isomers in the cis/trans region, i.e., Δ8,10- and Δ11,13-octadecadienoic acid, which had not been chromatographically resolved previously, Furthermore, the potential of this method was demonstrated by showing different Ag+-HPLC profiles exhibiting patterns of isomeric distributions for biological specimens from animals fed a diet containing a commerical CLA preparation, as well as for a commerical cheese product. 相似文献
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Axel Kramer Prof. Dr. Ojan Assadian Prof. Dr. H. Below Dr. rer. nat. Claudia Bender Aylin Hammann Bernd Hartmann Dr. Nils‐Olaf Hübner Dr. med. Thomas Kocher Prof. Dr. Jürgen Lademann Prof. Dr. Dr.‐Ing. Rutger Matthes Dipl. human. biol. Ina Koban Dipl. human. biol. Klaus‐Dieter Weltmann Prof. Dr. 《真空研究与实践》2010,22(2):33-38
Prospects of plasma medicine: Applications of Tissue Tolerable Plasmas (TTP) Based on the current knowledge on the physical properties and biological effects of tissue tolerable plasma (ttp) potential perspectives of plasma medicine are discussed. Currently, the foundations for the following medical applications of ttp are developed by an interdisciplinary research team: Prevention and/or treatment of diseases such as chronic wounds, skin and mucosal infectious diseases, localized tumors, promotion of angiogenesis, and tissue ablation Inhibition and/or elimination of biofilms by prevention of biofilm development due to surface treatment and/or plasma steered application of antimicrobial active layers with drug delivery function on foreign objects implanted into humans (implantable prosthesis, contact lenses, stents etc.) as well as elimination of biofilms by direct action of ttp on surfaces and tissues (chronic wounds, tooth surface, prosthesis) promotion of the incorporation of implants into viable tissue by changing the surface of materials (hydrophobicity) Promotion of penetration of topically applied drugs with therapeutic results Assessment of veterinary indications Improved cleaning performance in reprocessing of medical devices by surface modification. 相似文献
69.
We used social information processing theory to examine the effect of work–family conflict (WFC) at the work group level on individuals’ experience of WFC. Consistent with hypotheses, results suggest that WFC at the work group level influences individual WFC over and above the shared work environment and job demands. It was also observed that work group support and demographic dissimilarity moderate this relationship. Moderator analyses suggest that work group social support buffers WFC for individuals but is also associated with a stronger effect of work group WFC on individuals’ WFC. Moreover, the work group effect on individuals’ WFC was shown to be stronger for individuals who were demographically dissimilar to the work group in terms of sex and number of dependents. The interpretations and implications of these findings are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
P.R. Brito-Parada S.C. Kramer C.R. Wilson C.C. Pain S.J. Neethling J.J. Cilliers 《Chemical engineering science》2012,69(1):279-286
In this paper, a numerical model for the flow of foams in flotation cells in up to three dimensions is described. By using finite elements to solve Laplace's equation for a potential scalar, the flow pattern and velocity of the foam can be obtained. This has allowed, for the first time, the carrying out of numerical investigations of foam flow patterns regardless of the symmetry of the system. The numerical model has been implemented in Fluidity, a general purpose finite element method code that allows simulations to be carried out on anisotropic unstructured meshes. Such a model is of particular interest since other phenomena occurring in flotation depend on the foam velocity. Convergence tests that verify the numerical model are presented, and simulation results that showcase important features of the present implementation are discussed. 相似文献