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91.
Marine amoebae from waters of northwest Spain, with comments on a potentially pathogenic euryhaline species 总被引:1,自引:0,他引:1
M C Arias Fernandez E Paniagua Crespo M Marti Mallen M P Penas Ares M L Casro Casas 《The Journal of protozoology》1989,36(3):239-241
Of 17 species of free-living amoebae identified in various samples of salt water, only 1, Acanthamoeba polyphaga, is known to be a potential pathogen. While no deaths occurred when laboratory animals were inoculated with A. polyphaga to test for pathogenicity, the protozoa were present in the brain, liver and lungs of some but not all of the animals. 相似文献
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J. R. Poortmans E. Blommaert M. Baptista M. E. De Broe E. J. Nouwen 《European journal of applied physiology and occupational physiology》1997,76(1):88-91
Post-exercise proteinuria is a common phenomenon in healthy subjects. Previous studies have used albumin (Alb) and β2-microglobulin (β2-m) molecules as representatives of high- and low-molecular-weight proteins. Recently, more specific markers of the human
kidney proximal tubule have been used to identify the precise site of alterations. Active male subjects underwent two strenuous
runs, one 400-m run and one 3000-m run. Urine was collected from the subjects before and after each event. Total protein (TP),
Alb, α1-microglobulin (α1-m), β2-m, intestinal alkaline phosphatase (IAP), tissue-nonspecific alkaline phosphatase (TNAP) and N-acetyl-β-d-glucosaminidase (NAG) were determined for each sample. The short-distance run (400 m) resulted in the largest increases (P ≤ 0.05) in TP (31-fold), Alb (100-fold) and β2-m (164-fold) as compared to the long-distance run (3000-m). The α1-m excretion rates were increased to a lesser extent by the exercises. The IAP activity was slightly increased (+90%) by the
400-m run while the TNAP and NAG activities showed a 6.8-fold and a 3.6-fold increase, respectively, after this event. Smaller
increases were recorded for the long-distance run (P = 0.05). To conclude, the present investigation showed that: (1) post-exercise proteinuria is related to the absolute intensity
of exercise; (2) the impairment of protein reabsorption is revealed better by changes in Alb and β2-m; (3) changes in TNAP and NAG activities could reveal biochemical modifications that occur in the proximal tubule, particularly
at the S1-S2 segment.
Accepted: 31 January 1997 相似文献
94.
Utilization of the biogenic aliphatic organosulphonates taurine, isethionate, sulphoacetaldehyde and sulphoacetate was investigated in 100 soil and freshwater bacteria isolated on modified complete mineral salts medium. More than 90% could use all the compounds as sole sulphur sources, and some 10% used taurine and isethionate as sole carbon and energy, or sole carbon, energy and sulphur sources. None could mineralize sulphoacetaldehyde or sulphoacetate; however, two isolates capable of growth on sulphoacetate as sole carbon, energy and sulphur source were obtained by enrichment culture. The results suggest that in the majority of environmental bacteria the pathways of organosulphonate biodegradation may be independently controlled by the supply of carbon and sulphur to the cell, and that a number of routes may exist for cleavage of the organosulphonate C–S bond. 相似文献
95.
P Salgame A S Varadhachary L L Primiano J E Fincke S Muller M Monestier 《Nucleic acids research》1997,25(3):680-681
We describe a simple and convenient enzyme-linked immunosorbent assay (ELISA) for the detection of apoptosis in tissue culture. An early event in apoptosis is DNA fragmentation followed by release of nucleosomes into the cytoplasm. Our sandwich assay uses a pair of monoclonal antibodies specific for two nucleosomal epitopes to capture and detect cytoplasmic nucleosomes onto the ELISA plate. Our assay is about 500 times more sensitive than the detection of apoptotic DNA ladder by agarose electrophoresis and is especially suited for the testing of large numbers of samples. 相似文献
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Biophysics - A glutamate model of stroke was analyzed from the standpoint of the development of a typical pathological process that is thought to occur when major regulatory mechanisms are... 相似文献
99.
Does a long‐term shift in Wood Stork diet foreshadow adaptability to human‐induced rapid environmental change? 下载免费PDF全文
To preserve biodiversity, identifying at‐risk populations and developing conservation plans to mitigate the effects of human‐induced rapid environmental change (HIREC) are essential. Changes in diet, especially for food‐limited species, can aid in detecting populations being impacted by HIREC, and characterizing the quality, abundance, and temporal and spatial consistency of newly consumed food items may provide insight concerning the likelihood of a species persisting in a changing environment. We used Wood Storks (Mycteria americana) nesting in the Florida Everglades as a model system to study the possible effects of HIREC on a food‐limited population. We compared the diets of Wood Storks in 2013 and 2014 with those reported during the 1970s before major anthropogenic activities affected the Everglades system and prey availability. Wood Storks in our study consumed more large‐bodied sunfish species (Lepomis spp.), fewer native marsh fishes, and more non‐native fish species than during the 1970s. Large sunfish and non‐native fish are relatively rare in the drying pools of Everglades marshes where storks traditionally forage, suggesting that Wood Storks may be using novel foraging habitats such as created wetlands (i.e., canals and stormwater ponds). Although created wetlands have long hydroperiods conducive to maintaining large‐bodied fishes and could provide alternative foraging habitat when prey availability is reduced in natural marshes, additional studies are needed to determine the extent to which these wetlands are used by Wood Storks and, importantly, the quality of prey items potentially available to foraging Wood Storks in created wetlands. 相似文献
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