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排序方式: 共有284条查询结果,搜索用时 15 毫秒
1.
Hampel V Schwarz B Kempf C Köstlin R Schillinger U Küchenhoff H Fenske N Brill T Hirschberger J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(6):1340-1346
BACKGROUND: Recombinant feline interferon-omega (rFeIFN-omega) was tested as a treatment option for cats with fibrosarcoma to assess safety and feasibility. HYPOTHESIS: Treatment with rFeIFN-omega in cats with fibrosarcoma is safe and feasible. ANIMALS: Twenty domestic cats. METHODS: In an open-labeled uncontrolled clinical trial 12 injections of 1 x 10(6) U/kg rFeIFN-omega were administered over a 5-week period: the 1st through 4th injections were given intratumorally, and the 5th through 12th injections were administered subcutaneously at the tumor excision site. Wide surgical excision of the tumors was carried out after the 4th injection and before the 5th injection of rFeIFN-omega. A Common Terminology Criteria for Adverse Events (CTCAE) analysis was conducted. Flow cytometry of fibrosarcoma cells after incubation with rFeIFN-omega and recombinant feline interferon-gamma was performed to assess the biological effect of rFeIFN-omega. RESULTS: Changes in blood cell count, increases in serum aspartate-amino-transferase activity, serum bilirubin concentration, serum creatinine and serum electrolyte concentrations, weight loss, anorexia, increased body temperature, and reduced general condition were observed but were mostly minor (grade 1 and 2) and self limiting. Eosinophilia (P = .025), neutropenia (P = .021), and weight loss (P < .001) were statistically correlated with rFeIFN-omega-treatment (analysis of parameters before treatment and after 3 injections of rFeIFN-omega). Flow cytometry of 5 unrelated feline fibrosarcoma cell lines showed increased expression of major histocompatibility complex (MHC) class I molecules (P = .026) in response to in vitro incubation with rFeIFN-omega, whereas expression of MHC class II molecules was not affected significantly. CONCLUSIONS AND CLINICAL IMPORTANCE: RFeIFN-omega for the treatment of feline fibrosarcoma is safe, well tolerated, and can be easily performed in practice. To assess the efficacy of the treatment, it should be tested in a placebo-controlled trial. 相似文献
2.
A low-selenium diet increases thyroxine and decreases 3,5,3'triiodothyronine in the plasma of kittens 总被引:1,自引:0,他引:1
Yu S Howard KA Wedekind KJ Morris JG Rogers QR 《Journal of animal physiology and animal nutrition》2002,86(1-2):36-41
The effect of a low-selenium diet on thyroid hormone metabolism was investigated in growing kittens. Twelve specific-pathogen-free kittens with ages ranging from 16 to 18 weeks were divided into two groups of equal number with equal sex distribution in each group. One group was fed a yeast-based low-selenium diet (0.02 mg Se/kg diet) while the other group was fed the same diet supplemented with Na2 SeO3 at 0.4 mg Se/kg diet for 8 weeks. Food intake, body weight and body weight gain were not affected by the low-Se diet during the study period. However, kittens given the low-Se diet had significantly reduced plasma selenium concentration and glutathione peroxidase activity. Plasma total thyroxine (T4) increased and total 3,5,3'triiodothyronine (T3) decreased significantly in kittens fed the low-Se diet at the end of the study. These results suggest that type I deiodinase in cats is a selenoprotein- or a selenium-dependent enzyme. 相似文献
3.
Steven C Zicker Karen J Wedekind Dennis E Jewell 《Veterinary Clinics of North America: Small Animal Practice》2006,36(6):1183-98, v
Nutritional antioxidants have experienced a surge in research and interest in the past 20 years. this surge may be attributed to the improved methodology for investigation as well as the focus on diseases and aging processes related to oxidative stress that lend themselves to opportunistic outcomes. As such, the field of veterinary nutritional antioxidant research is also beginning to yield some interesting results, albeit, small in number compared with laboratory animals and human beings. Nonetheless, this article updates the practitioner on recent advances in research involving nutritional antioxidant applications in companion animals. 相似文献
4.
Quality assessment of thermally modified wood has evolved as one of the major fields in the research on thermal modification of wood. This study investigates NIR spectroscopy in combination with the pattern recognition method of soft independent modeling of class analogies (SIMCA). Focus is put on identifying different treatment intensities of thermally modified samples of beech, ash, and Norway spruce. The results indicate that SIMCA classification based on NIR spectroscopy could be used for quality control of thermally modified wood. The method might be applicable for producers (pre-delivery checks) and customers (reception control). However, transfer from laboratory to industrial conditions needs further investigation. 相似文献
5.
Combining agent-based and stock-flow modelling approaches in a participative analysis of the integrated land system in Reichraming, Austria 总被引:1,自引:0,他引:1
Veronika Gaube Christina Kaiser Martin Wildenberg Heidi Adensam Peter Fleissner Johannes Kobler Juliana Lutz Andreas Schaumberger Jakob Schaumberger Barbara Smetschka Angelika Wolf Andreas Richter Helmut Haberl 《Landscape Ecology》2009,24(9):1149-1165
The integrated modelling of coupled socio-ecological systems in land-change science requires innovative model concepts capable of grasping the interrelations between socioeconomic and natural components. Here, we discuss the integrated socio-ecological model SERD (Simulation of Ecological Compatibility of Regional Development) that was developed for the municipality of Reichraming in Upper Austria in a participative 2-year process involving local stakeholders. SERD includes three main components: (1) an agent-based actors module that simulates decisions of farmsteads, the municipal administration and other important actors; (2) a spatially explicit (GIS based) land-use module that simulates land-use change at the level of individual parcels of land and (3) an integrated socio-ecological stock-flow module that simulates carbon and nitrogen flows through both socioeconomic and ecological system compartments. We report on outcomes of a scenario analysis that outlines possible future trajectories depending on both external (e.g. agricultural subsidies and prices) and internal (e.g. innovation, willingness to co-operate) factors. We find that both external and internal factors can affect the behaviour of the integrated system considerably. Local and regional policies are found to be able to counteract adverse global socioeconomic conditions to some extent, but not to reverse the trend altogether. We also find strong interdependencies between socioeconomic and ecological components of the system. Fully evaluating these interdependencies is, however, not possible at the local scale alone and will require explicit consideration of higher-level effects in future research. 相似文献
6.
7.
Helmut Brandl 《Small-Scale Forestry》2006,5(1):145-159
Today the Black Forest is an internationally renowned tourist region in Germany. For centuries the Black Forest remained as
a low mountain range regarded as not suitable for settlement due to its unfavourable climatic conditions and difficult terrain.
Clearing the dense forests and settlement therefore started at a historically late stage compared to other regions of Germany,
about 1000 years ago. Due to the special conditions in this area, the structure of the settlement had to be quite different
to those landscapes with more favourable conditions for agriculture. A single-farm settlement developed, farms situated 200
to 400 m away from each other, surrounded by meadows, agricultural land and forests and owned by the farmer’s family. This
structure has remained in some areas until today; in other areas different types of settlement took place, and great changes
occurred during history. A special type of agroforestry — a slash-and-burn-management of forests — also took place 150 to
200 years ago. 相似文献
8.
Ohne Zusammenfassung 相似文献
9.
Thomas?HolstEmail author Helmut?Mayer Dirk?Schindler 《European Journal of Forest Research》2004,123(1):13-28
Within the framework of an interdisciplinary project on the effects of climate and forest management on beech-dominated deciduous forests (Swabian Jura, south-western Germany), forest meteorological investigations are carried out to analyse the influences of exposure and canopy density on the microclimate within various beech stands (Fagus sylvatica L.). This second paper of the series Microclimate within beech stands focuses on the thermal conditions that exist mainly in the near-surface layer at different test plots. They were analysed by air temperature, Ta, (at 1.5 m a.g.l) and soil temperature, Ts, at six depths measured continuously in the period 1999–2003. The main results can be summarized as follows. (1) The thermal situation within the beech stands described by Ta depended primarily on the turbulent air-mass exchange conditions which were based on the slope-specific energy balance of the forest floor and advective heat fluxes. (2) The thermal situation within the soil described by Ts at 3 and 20 cm depth was governed by the molecular heat transport. Therefore, the heating and cooling rates of Ts were always lower than for Ta. Higher Ta and Ts values for the test plots on the SW slope showed that the thermal conditions within the beech stands depended primarily on the exposure. (3) Based on slope-specific differences of daily extremes of Ta and Ts at 3 cm depth between the silviculturally treated and control plots, the influence of the more pronounced height growth of the understorey vegetation under the near-surface thermal conditions could be clearly verified for the NE slope.Abbreviations PAR Photosynthetically active radiation - PAI Plant area index - LAI Leaf area index 相似文献
10.
Atawodi SE Pfundstein B Haubner R Spiegelhalder B Bartsch H Owen RW 《Journal of agricultural and food chemistry》2007,55(24):9824-9828
Varieties of kola nuts (Cola nitida alba, Cola nitida rubra A. Chev, and Cola acuminata Schott & Endl), a group of popular Nigerian and West African stimulants, were analyzed for their content of secondary plant metabolites. The three varieties of the kola nuts contained appreciable levels of (+)-catechin (27-37 g/kg), caffeine (18-24 g/kg), (-)-epicatechin (20-21 g/kg), procyanidin B 1 [epicatechin-(4beta-->8)-catechin] (15-19 g/kg), and procyanidin B2 [epicatechin-(4beta-->8)-epicatechin] (7-10 g/kg). Antioxidant capacity of the extracts and purified metabolites was assessed by two HPLC-based and two colorimetric in vitro assays. Extracts of all varieties exhibited antioxidant capacity with IC 50 values in the range 1.70-2.83 and 2.74-4.08 mg/mL in the hypoxanthine/xanthine oxidase and 2-deoxyguanosine HPLC-based assays, respectively. Utilization of HPLC-based assays designed to reflect in situ generation of free radicals (e.g., HO(*)), as opposed to general assays (DPPH, FRAP) in common use which do not, indicate that, of the major secondary plant metabolites present in kola nut extracts, caffeine is potentially the more effective cancer chemopreventive metabolite in terms of its antioxidant capacity. 相似文献