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61.
Guillermo A. Galván István Parádi Karin Burger Jacqueline Baar Thomas W. Kuyper Olga E. Scholten Chris Kik 《Mycorrhiza》2009,19(5):317-328
Diversity and colonization levels of naturally occurring arbuscular mycorrhizal fungi (AMF) in onion roots were studied to
compare organic and conventional farming systems in the Netherlands. In 2004, 20 onion fields were sampled in a balanced survey
between farming systems and between two regions, namely, Zeeland and Flevoland. In 2005, nine conventional and ten organic
fields were additionally surveyed in Flevoland. AMF phylotypes were identified by rDNA sequencing. All plants were colonized,
with 60% for arbuscular colonization and 84% for hyphal colonization as grand means. In Zeeland, onion roots from organic
fields had higher fractional colonization levels than those from conventional fields. Onion yields in conventional farming
were positively correlated with colonization level. Overall, 14 AMF phylotypes were identified. The number of phylotypes per
field ranged from one to six. Two phylotypes associated with the Glomus mosseae–coronatum and the G. caledonium–geosporum species complexes were the most abundant, whereas other phylotypes were infrequently found. Organic and conventional farming
systems had similar number of phylotypes per field and Shannon diversity indices. A few organic and conventional fields had
larger number of phylotypes, including phylotypes associated with the genera Glomus-B, Archaeospora, and Paraglomus. This suggests that farming systems as such did not influence AMF diversity, but rather specific environmental conditions
or agricultural practices.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Authors Guillermo A. Galván and István Parádi contributed equally to this research and share first co-authorship. 相似文献
62.
K. Kraaier P. M. J. Verhorst P. F. H. M. van Dessel A. A. M. Wilde M. F. Scholten 《Netherlands heart journal》2009,17(3):101-106
With the introduction of the implantable cardioverter defibrillator (ICD), patients can be protected against sudden cardiac death (SCD) due to ventricular arrhythmia (VA). Guidelines have been drawn up for selecting patients for primary and secondary prophylaxis. However, most ICD recipients today who receive an ICD for primary prevention will not experience a life-threatening VA requiring antitachypacing or shock therapy. Better risk stratification is desirable with efficacy, costs and complication rate in mind. An overview is presented of widely accepted and potentially valuable risk markers and the role they may play in better identifying candidates for ICD therapy. (Neth Heart J 2009;17:101–6.) 相似文献
63.
Mark E. Schnute Patrick M. O’Brien Joe Nahra Mark Morris W. Howard Roark Cathleen E. Hanau Peter G. Ruminski Jeffrey A. Scholten Theresa R. Fletcher Bruce C. Hamper Jeffery N. Carroll William C. Patt Huey S. Shieh Brandon Collins Alexander G. Pavlovsky Katherine E. Palmquist Karl W. Aston Jeffrey Hitchcock Michael D. Rogers Joseph McDonald Teresa Sunyer 《Bioorganic & medicinal chemistry letters》2010,20(2):576-580
64.
Agars with different performance in bioassays were analysed for physical and chemical properties. Agars with the highest
gel strength had the best performance. Good performance was also related to a low pH of a suspension of agars and to a low
sulphur content. The diffusion rate of ions in gels differed between agars, but could not explain differences in agar performance.
The time of autoclaving had a marked effect on the gel strength, however, without affecting the performance. Chemical analysis
revealed large differences between agars. The best agars had a relatively low salt content. One of the best agars had an extremely
high content of trace elements. Agar impurities, especially of the trace elements were tightly bound to the agars. Up to 30%
of the Murashige and Skoog (MS) salts were also immobilized in the gel. At pH 4.2, less nitrogen and phosphate were available
from the MS medium than at pH 5.7. Chlorine could be washed out completely and appeared to be a good marker for agar quality
and purity. With AgNO3, chlorine contamination could easily be visualized.
Received: 28 April 1996 / Revision received: 15 December 1996 / Accepted: 20 January 1997 相似文献
65.
Unusual molecular evolution of an Adh pseudogene in Drosophila 总被引:2,自引:0,他引:2
Sullivan DT; Starmer WT; Curtiss SW; Menotti-Raymond M; Yum J 《Molecular biology and evolution》1994,11(3):443-458
66.
67.
Cultures from 80 out of 1667 patients (4.8%) admitted consecutively to a tuberculosis hospital grew atypical mycobacteria. With four strict criteria it was concluded that the mycobacteria isolated were the cause of the disease in 47 of these patients. The majority of these organisms were resistant to most, and in seven cases to all, of the antituberculous drugs. Ten patients responded poorly to treatment and 14 patients (30%) died, 8 of these from uncontrollable pulmonary infection with the atypical organisms. It is suggested that a recent, simplified classification of mycobacteria proposed by Runyon be adopted. 相似文献
68.
69.
Scholten E 《Plastic and reconstructive surgery》2000,106(3):737-738