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71.
Rising atmospheric carbon dioxide (CO2) concentration is increasingly affecting food production but how plant diseases will influence production and quality of food under rising CO2 is not well understood. With increased plant biomass at high CO2 the stubble‐borne fungal pathogen Fusarium pseudograminearum causing crown rot (CR) of wheat may become more severe. We have studied inoculum production by Fusarium using fungal biomass per unit wheat stubble, stem browning from CR and the saprophytic fitness of Fusarium strains isolated from two wheat varieties grown in 2007 and 2008 at ambient and elevated CO2 in free‐air CO2 enrichment (FACE) with or without irrigation and once in a controlled environment. Fungal biomass, determined using primers for fungal ribosomal 18s and the TRI5 gene, increased significantly at elevated CO2 in two of the three studies. Stem browning increased significantly at elevated CO2 in the 2007 FACE study. At elevated CO2 increased stem browning was not influenced by irrigation in a susceptible variety but in a resistant variety stem browning increased by 68% without irrigation. Wheat variety was significant in regression models explaining stem browning and Fusarium biomass but pathogen biomass at the two CO2 levels was not significantly linked to stem browning. Fusarium isolates from ambient and elevated CO2 did not differ significantly in their saprophytic fitness measured by the rate of colonization of wheat straw. We show that under elevated CO2Fusarium inoculum in stubbles will be amplified from increased crop and pathogen biomass while unimpeded saprophytic fitness will retain its effectiveness. If resistant varieties cannot completely stop infection, Fusarium will rapidly colonize stubble to further increase inoculum once the crop is harvested. Research should move beyond documenting the influence of elevated CO2 to developing disease management strategies from improved knowledge of pathogen biology and host resistance under rising CO2.  相似文献   
72.
The tumor suppressor, QM, has been cloned and characterized from various model organisms such as human, plant and invertebrates. Yet, it has not been seriously investigated for its role in conjunction with antiviral mechanisms involving innate insect immunity. From the expressed sequence tag (ESTs) project, conducted with larval cDNA library of cabbage butterfly, Pieris rapae, a partial fragment (718 bp) of QM homologue, termed PrQM containing 660 bp long open reading frame (ORF) encoding protein of 219 amino acids was identified. In silico analysis of PrQM ORF revealed the presence of ribosomal protein L10a/L10e type domain. Phylogenetic analysis of the P. rapae QM‐like protein showed high amino acid sequence similarity with other PrQM polypeptides identified from Heliothis virescenes (95%), Plutella rapae (92%), Bombyx mori (92%), Drosophila melanogaster (89%), and Polyrhachis vicina (85%). The butterfly QM has the closest phylogenetic relationship to a moth (Hv) QM homologue. Further investigations revealed the expression of PrQM at all developmental stages, with pronounced presence at the egg stage. In addition, spatial pattern analysis indicated its high expression in the head, salivary gland, integument and fat body with visible presence in Malpighian tubule and gut. Time course expression studies conducted after immune‐challenge with lipoteichoic acid (LTA) showed the induction of PrQM mRNA at 12 h and 24 h after challenge and also in response to granulovirus (GV). Results of this investigation therefore suggest possible role of QM‐like proteins from Pieris rapae to be involved in innate antiviral immune responses. Further elucidation on the precise function of PrQM during antiviral immune responses by using RNA interference remains a viable research front.  相似文献   
73.
This article describes the results of the WPA-WHO Global Survey of 4,887 psychiatrists in 44 countries regarding their use of diagnostic classification systems in clinical practice, and the desirable characteristics of a classification of mental disorders. The WHO will use these results to improve the clinical utility of the ICD classification of mental disorders through the current ICD-10 revision process. Participants indicated that the most important purposes of a classification are to facilitate communication among clinicians and to inform treatment and management. They overwhelmingly preferred a simpler system with 100 or fewer categories, and over two-thirds preferred flexible guidance to a strict criteria-based approach. Opinions were divided about how to incorporate severity and functional status, while most respondents were receptive to a system that incorporates a dimensional component. Significant minorities of psychiatrists in Latin America and Asia reported problems with the cross-cultural applicability of existing classifications. Overall, ratings of ease of use and goodness of fit for specific ICD-10 categories were fairly high, but several categories were described as having poor utility in clinical practice. This represents an important focus for the ICD revision, as does ensuring that the ICD-11 classification of mental disorders is acceptable to psychiatrists throughout the world.  相似文献   
74.
Abscisic acid (ABA)-induced stomatal closure is mediated by a complex, guard cell signalling network involving nitric oxide (NO) as a key intermediate. However, there is a lack of information concerning the role of NO in the ABA-enhanced stomatal closure seen in dehydrated plants. The data herein demonstrate that, while nitrate reductase (NR)1-mediated NO generation is required for the ABA-induced closure of stomata in turgid leaves, it is not required for ABA-enhanced stomatal closure under conditions leading to rapid dehydration. The results also show that NO signalling in the guard cells of turgid leaves requires the ABA-signalling pathway to be both capable of function and active. The alignment of this NO signalling with guard cell Ca2+-dependent/independent ABA signalling is discussed. The data also highlight a physiological role for NO signalling in turgid leaves and show that stomatal closure during the light-to-dark transition requires NR1-mediated NO generation and signalling.  相似文献   
75.
76.
The lymphoabdominal involvement in the sub-acute form of paracoccidioidomycosis shows a wide variety of clinical manifestations, ranging from fever and lymph node enlargement to infiltration of all abdominal organs, which can lead to a situation of abdominal surgical emergency. This case report presents paracoccidioidomycosis mimicking carcinoma of the biliary tract, The purpose of this paper is to call the general physician’s attention for this important differential diagnosis of abdominal masses. Although paracoccidioidomycosis is rarely encountered in the United States and Europe, it should be considered in patients who are suspected of having a fungal infection and have had previous exposure in an endemic area for this disease.*Fábio Luis Silva do Prado and Renata Prado contributed equally to this work.  相似文献   
77.
1. Constitutive and ethoxyquin hydrochloride (EQ-HCl)-induced hepatic glutathione (GSH) S-transferase, GSH reductase, and GSH peroxidase activities were determined in 5 strains of 8-10 week old inbred male mice. 2. The constitutive GSH S-transferase (GST) activity varied from 2.9 (SJL/JCR) to 8.9 (C57BL/6NCR) mumol product formed/min/mg protein and the corresponding values for the EQ-HCl-treated mice were in the range of 15.3-25.3 mumol product formed/min/mg protein. 3. EQ-HCl induced GST activity in all the strains examined and this contrasted to the induction activity of Aroclor 1254 which was strain-dependent. GST activity was induced 2.9-fold in Aroclor 1254-responsive (C57BL/6) and 2.8-fold in non-responsive (DBA/2) mice, respectively.  相似文献   
78.
In this paper, a total of four species of the genus Lispe are treated. Of these, L. assimilis Wiedemann and L. litorea Fallén are reported for the first time in Korea. A key to the Korean species, their domestic localities, and some illustrations are given.  相似文献   
79.
Three species of the genus ScathophagaS. mellipes (Coquillet), S. scybalaria (Linnaeus) and S. stercoraria (Linnaeus) – are treated in this study. Of these, S. scybalaria (Linnaeus) is reported for the first time from Korea. A key to the Korean species, their domestic localities and some illustrations are given.  相似文献   
80.
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