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991.
    
Alterations of the phospholipid (PL) compositions of body fluids are assumed to be indicative of inflammatory diseases, e.g. rheumatoid arthritis (RA). Recently, we have shown that particularly the phosphatidylcholine/lysophosphatidylcholine (PC/LPC) ratio determined in human synovial fluids (SF) and sera represents a reliable measure of the inflammatory state in RA patients. However, it is not yet clear to what extent the PC/LPC ratio is also affected by nutrition habits. In the present study, the PL and the corresponding acyl chain compositions of human body fluids (SF and serum of RA patients as well as serum from healthy volunteers) are compared with those of two other mammalian species (horses and dogs suffering from degenerative joint diseases as well as healthy controls) by high-resolution 31P-nuclear magnetic resonance (NMR) spectroscopy and matrix-assisted laser desorption and ionization time-of-flight mass spectrometry (MALDI-TOF MS). The most important result of this study is that the PL compositions of SF and serum of horse and dog are comparable with those of human body fluids. Compared with humans, however, the horse body fluid contains less PCs with highly unsaturated arachidonoyl residues, while that of dogs possesses the highest content of arachidonoyl-containing PC. These species-related differences stem primarily from different nutrition habits (meat vs. plants).  相似文献   
992.
993.
Pyloric and oesophageal dysfunction in the cat   总被引:3,自引:0,他引:3  
The paper describes the symptoms, diagnosis and treatment of pyloric stenosis in thirteen cats, associated in some animals, with megalo-oesophagus.  相似文献   
994.
  总被引:14,自引:0,他引:14  
Trypanosoma brucei grew in the presence of bovine fibroblast-like cells in Hepes-buffered RPMI 1640 medium with 20 percent fetal bovine serum for more than 220 days at 37 degrees C. The organisms grown in this system were infective to mammalian hosts, retained the morphological and biochemical characteristics of long slender bloodstream forms, and displayed variant-antigen on their surfaces.  相似文献   
995.
    
Bacteria from the food leaves and faeces of millipedes maintained in group cultures (12 animals) for 24 h were counted. Dilution plating and direct observation both showed significant increases in bacterial populations (10–100 fold) after passage through the gut. In cultures of single animals the increases were primarily the result of rapid growth in the midgut, though there was some evidence of further proliferation in the hindgut and faeces. The ratio of viable counts to direct counts was lower in litter than in the gut and faeces, suggesting that the gut environment enhanced bacterial growth and viability. Correlation between counts from guts and food leaves further indicated that the growth response was by the litter microflora and not indigenous gut symbionts.  相似文献   
996.
An investigation of the carbon economy of single S184 white clover plants nodulated with an effective strain of Rhizobium trifolii growing on N-free nutrient solution and supplied with 150 parts/106 N as NH4NO3 has shown that 10% more of the C fixed per day is available for growth in the plants supplied with combined N. The difference between the two groups of plants is a result of higher respiratory activity in the roots of plants growing exclusively on N2. In terms of shoot growth, however, the difference in growth rate is likely to be less than 10%, because the rate of root growth is greater in the plants supplied with a moderate level of combined N. There is no evidence that NO-3 and CO2 compete for photosynthetically produced reductant in the leaves of plants grown on N2+NH4NO3, since no reduction in net photosynthesis was observed in plants assimilating combined N. An experiment carried out on detached leaflets of white clover grown on N2 and on N2+ NH4NO3 has shown that NO-3 -reducing activity is present in the leaflets of plants grown on N2+ NH4NO3 but not in plants grown on N2 and that the activity is light-dependent. Measurements of 14CO2 respired in the light and dark by leaflets previously allowed to photosynthesize 14CO2 showed that the ratio of 14CO2 output in the light to 14CO2 output in the dark was no higher in plants grown on N2+ NH4NO3 than in plants grown on N2. This observation is consistent with the finding that N source does not affect net photosynthesis in whole plants.  相似文献   
997.
    
Hemoglobin G Taegu, an electrophoretically slow hemoglobin with a structural anomaly believed to be in the beta-T-3 section of the beta chain, was the only variant found among 6700 normal Koreans. Four subjects, 0.06 percent, had the G-hemoglobin variant in addition to normal hemoglobin A. Hemoglobin E, known in numerous groups from Southeast Asia and the variant most frequently seen in Chinese subjects, was not found among the Koreans we tested.  相似文献   
998.
  总被引:1,自引:0,他引:1  
Some characteristics of the species complex Pennisetum section Brevivalvula are polyploidy and apomixis. Four euploidy levels (x = 9) were assessed by DAPI-flow cytometry for 304 plants of the section, distributed among five species: P. hordeoides (2n = 36, 54), P. pedicellatum (2n = 36, 45, 54), P. polystachion (2n = 18, 36, 45, 54), P. setosum (2n = 54), and P. subangustum (2n = 18, 36, 54). The geographical distribution of the ploidy levels seems to be related to major ecological zones of West Africa. The hilly regions displayed a higher ploidy diversity than the others; diploid populations of the annual species P. polystachion and P. subangustum were found. Genotypic variation expressed by isozyme polymorphism did not show any significant difference between the diploid, sexual populations and the polyploid, apomictic populations of these two species. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
999.
Aerobically spoiled silage has often been shown to harbour dangerously high levels of Listeria monocytogenes. This paper investigates the dynamics of aerobic deterioration in a silage bale as it occurs close to a site of damage to the cover. The underlying aim was to enable prediction of the extent of the silage that may become suitable for Listeria growth during the course of storage. In order to meet these objectives, a model was formulated that represents the microbiology of the deterioration process and the transport of oxygen and heat through the silage. The geometry of the system was exploited to ensure that the model is computationally tractable. The model was used to evaluate the effect of silage pH and puncture size on the risk of Listeria contamination. Although the hazardous fraction was seen to be relatively insensitive to the initial pH of the silage, it increased rapidly with puncture size. However, a small puncture can result in the 'loss' of a considerable fraction of the bale because of the relatively long time scale over which bales are stored.  相似文献   
1000.
Deep root water uptake and hydraulic redistribution (HR) have been shown to play a major role in forest ecosystems during drought, but little is known about the impact of climate change, fertilization and soil characteristics on HR and its consequences on water and carbon fluxes. Using data from three mid-rotation loblolly pine plantations, and simulations with the process-based model MuSICA, this study indicated that HR can mitigate the effects of soil drying and had important implications for carbon uptake potential and net ecosystem exchange (NEE), especially when N fertilization is considered. At the coastal site (C), characterized by deep organic soil, HR increased dry season tree transpiration (T) by up to 40%, and such an increase affected NEE through major changes in gross primary productivity (GPP). Deep-rooted trees did not necessarily translate into a large volume of HR unless soil texture allowed large water potential gradients to occur, as was the case at the sandy site (S). At the Piedmont site (P) characterized by a shallow clay-loam soil, HR was low but not negligible, representing up to 10% of T. In the absence of HR, it was predicted that at the C, S and P sites, annual GPP would have been diminished by 19, 7 and 9%, respectively. Under future climate conditions HR was predicted to be reduced by up to 25% at the C site, reducing the resilience of trees to precipitation deficits. The effect of HR on T and GPP was predicted to diminish under future conditions by 12 and 6% at the C and P sites, respectively. Under future conditions, T was predicted to stay the same at the P site, but to be marginally reduced at the C site and slightly increased at the S site. Future conditions and N fertilization would decrease T by 25% at the C site, by 15% at the P site and by 8% at the S site. At the C and S sites, GPP was estimated to increase by 18% and by >70% under future conditions, respectively, with little effect of N fertilization. At the P site, future conditions would stimulate GPP by only 12%, but future conditions plus N fertilization would increase GPP by 24%. As a consequence, in all sites, water use efficiency was predicted to improve dramatically with future conditions. Modeling the effect of reduced annual precipitation indicated that limited water availability would decrease all carbon fluxes, including NEE and respiration. Our simulations highlight the interactive effects of nutrients and elevated CO(2), and showed that the effect of N fertilization would be greater under future climate conditions.  相似文献   
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