abstract regarding to this issue that nitrogen is one of the main essential elements for plant that growth and efficiency of plant is related to it, and on the other hand most of the water and soil resources in iran are alkaline; in order to evaluation of the interactive effect of different concentrations of sodium bicarbonate and nitrogen form on snap bean in hydroponic system, this research w...

Paraquat, a quaternary ammonium bipyridyl herbicide, produces degenerative lesions in the lung after systemic administration to man and animals. The pulmonary toxicity of paraquat resembles in several ways the toxicity of several other lung toxins, including oxygen, nitrofurantoin and bleomycin. Although a definitive mechanism of toxicity of paraquat has not been delineated, a cyclic single ele...

Ammonium toxicity resulted in morphological modifications of tomato leaf chloroplasts. The chloroplasts, which are normally flattened around the protoplast periphery, became ellipsoidally rounded and dispersed through the protoplasm. The first apparent effect of plastid degradation was development of many vesicles from the fretwork. Later the grana lamellae swelled, and some disappeared. Eventu...

References 1 Greiner, S. et al. (1999) Ectopic expression of a tobacco invertase inhibitor homolog prevents cold-induced sweetening of potato tubers. Nat. Biotechnol. 17, 708–711 2 Hemberg, T. (1985) Potato rest. In Potato Physiology (Li, P.H., ed.), pp. 353–388, Academic Press 3 Suttle, J.C. (1995) Postharvest changes in endogenous ABA levels and ABA metabolism in relation to dormancy in potat...

Vulcanodinium rugosum, a recently described dinoflagellate species producing a potent neurotoxin (pinnatoxin G), has been identified in French Mediterranean lagoons and was responsible for recurrent episodes of shellfish toxicity detected by mouse bioassay. Until now, the biology and physiology of V. rugosum have not been fully investigated. We studied the growth characteristics and toxicity of...

Ammonium (NH4) toxicity is an issue of global ecological and economic importance. In this review, we discuss the major themes of NH4 toxicity, including the occurrence of NH4 in the biosphere, response differences to NH4 nutrition among wild and domesticated species, symptoms and proposed mechanisms underlying toxicity, and means by which it can be alleviated. Where possible, nitrate (NO3) nutr...

New evidences have recently emerged from studies in yeast and in higher eukaryotes showing the importance of nutrient balance in dietary regimes and its effects on longevity regulation.We have previously shown that manipulation of ammonium concentration in the culture and/or aging medium can drastically affect chronological lifespan (CLS)of Saccharomyces cerevisiae, especially in amino acid res...

Ammonium ions wastewater pollution has become one of the most serious environmental problems today. The treatment of ammonium ions is a special concern due to their recalcitrance and persistence in the environment. In recent years, various methods for ammonium ion removal from wastewater have been extensively studied. This paper reviews the current methods that have been used to treat ammonium ...

The history of life is fi lled with examples of one species diverging into several, even thousands, each with unique traits geared to the demands of its ecological niche. In the textbook case of adaptive radiation, an ancestral fi nch species landed on the Galapagos Islands just a few million years ago, and evolved into 13 new species with specialized beaks adapted to exploiting the various see...

The characteristics of cell adsorption and pinocytotic uptake of diphtheria toxin by several mammalian cell types were studied. Purified toxin iodinated by a solid-state lactoperoxidase method provided preparations of high specific activity and unaltered biological activity. Dephtheria toxin-sensitive HEp-2 cells and guinea pig macrophage cultures were compared with resistant mouse L-929 cells....