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61.
Duckweeds as crop plants Members of the plant family Lemnaceae (duckweeds) are not only interesting because they represent the smallest flowering plants; they possess also the fastest rates of producing biomass. As aquatic plants, duckweed production is not in competition with other agricultural crops that require fertile land while the cultivation of duckweeds does not contribute to further eutrophication of surface water. Instead, they can be cultivated on municipal or agricultural waste water and remove the nutrients during their propagation and growth. Duckweeds can thus be used for cleaning of waste water and the resulting biomass can be valuable starting material for animal feeds and the production of biofuels. Research focusing on these goals has begun to transfer from research laboratories to pilot plants in different parts of the world, e.g. in New Jersey and North Carolina, USA; Chengdu, P. R. China; and Armidale, Australia.  相似文献   
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The classic myotonic dystrophy, Steinert’s disease (DM1) was first described in 1909, and the second type, Ricker’s disease (DM2), in 1994. In 1992 the disease-causing mutation in DM1 was identified as a CTG repeat in the DMPK gene on chromosome 19q, and in 2001 the DM2 mutation was identified as a CCTG repeat expansion in the ZNF9 gene on chromosome 3q. Multisystemic symptoms of the diseases affect skeletal muscle, brain, eye, heart, and the endocrine system. The pathogenesis of both forms seems to be based on a gain-of-function RNA mechanism and on alterations in RNA metabolism and spliceopathy. Our review focuses on clinical features, diagnostic techniques, and new aspects of molecular pathogenesis and therapy.  相似文献   
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The monogenic inherited isolated alopecias comprise a group of clinically and genetically heterogeneous forms of hairlessness or hair loss. Clinical classification of the isolated alopecias is based on the onset of the disorder, the regions affected, and the structure of the hair shaft. Men and women are equally affected, and the mode of inheritance is autosomal dominant or autosomal recessive. Since the identification of the keratin gene KRT86 as a cause of the so-called monilethrix in 1997, mutations in nine other genes have been identified for various isolated alopecias. These include other keratin genes for monilethrix (KRT81 and KRT83), the hairless gene for atrichia congenita/papular atrichia, the corneodesmosin gene for the autosomal dominant form of hypotrichosis simplex, and the genes desmoglein 4, lipase H, and the G-protein-coupled receptor P2RY5 (LPAR6) for the autosomal recessive forms of hypotrichosis. Molecular genetic and pathophysiological studies of these rare disorders of hair development have contributed significantly to our understanding of the basic mechanisms of hair loss as well as the physiological mechanisms of hair growth.  相似文献   
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Early acquisition of Pseudomonas aeruginosa is associated with a poorer prognosis in patients with cystic fibrosis. We investigated whether polymorphisms in CD14, the lipopolysaccharide receptor, increase the risk of early infection. Forty-five children with cystic fibrosis were investigated with annual bronchoalveolar lavage (BAL) and plasma sCD14 levels. Plasma sCD14 levels were significantly lower in children from whom P.aeruginosa was subsequently isolated (492.75 μg/ml vs. 1339.43 μg/ml, p = 0.018). Those with the CD14 -159CC genotype had a significantly increased risk of early infection with P.aeruginosa suggesting that CD14 C-159T plays a role in determining the risk of early infection with P.aeruginosa.  相似文献   
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