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51.
Trocha LK Kałucka I Stasińska M Nowak W Dabert M Leski T Rudawska M Oleksyn J 《Mycorrhiza》2012,22(2):121-134
Non-native tree species have been widely planted or have become naturalized in most forested landscapes. It is not clear if
native trees species collectively differ in ectomycorrhizal fungal (EMF) diversity and communities from that of non-native
tree species. Alternatively, EMF species community similarity may be more determined by host plant phylogeny than by whether
the plant is native or non-native. We examined these unknowns by comparing two genera, native and non-native Quercus robur and Quercus rubra and native and non-native Pinus sylvestris and Pinus nigra in a 35-year-old common garden in Poland. Using molecular and morphological approaches, we identified EMF species from ectomycorrhizal
root tips and sporocarps collected in the monoculture tree plots. A total of 69 EMF species were found, with 38 species collected
only as sporocarps, 18 only as ectomycorrhizas, and 13 both as ectomycorrhizas and sporocarps. The EMF species observed were
all native and commonly associated with a Holarctic range in distribution. We found that native Q. robur had ca. 120% higher total EMF species richness than the non-native Q. rubra, while native P. sylvestris had ca. 25% lower total EMF species richness than non-native P. nigra. Thus, across genera, there was no evidence that native species have higher EMF species diversity than exotic species. In
addition, we found a higher similarity in EMF communities between the two Pinus species than between the two Quercus species. These results support the naturalization of non-native trees by means of mutualistic associations with cosmopolitan
and novel fungi. 相似文献
52.
Cantin LD Bayrakdarian M Buon C Grazzini E Hu YJ Labrecque J Leung C Luo X Martino G Paré M Payza K Popovic N Projean D Santhakumar V Walpole C Yu XH Tomaszewski MJ 《Bioorganic & medicinal chemistry letters》2012,22(7):2565-2571
Purinergic receptor P2X3 has been linked to analgesia in a number of pre-clinical models of pain, and is expressed in the human pain perception pathway. Only few P2X3-selective antagonists have been reported to date. This Letter describes the SAR and in vivo analgesic profile of a novel scaffold of selective P2X3 antagonists. 相似文献
53.
Agnieszka Janiak Stanis?aw Piórko Andrea Matros Hans-Peter Mock Miros?aw Kwa?niewski Karolina Chwia?kowska Beata Chmielewska Iwona Szarejko 《Journal of applied genetics》2012,53(4):363-376
The mechanisms of root hair formation have been studied extensively in Arabidopsis but knowledge about these processes in monocot species is still limited, especially in relation to the proteome level. The aim of this study was to identify the proteins that are involved in the initiation and the early stage of root hair tip growth in barley using two-dimensional (2D) electrophoresis and mass spectrometry. A comparison of proteins that accumulate differentially in two root hair mutants and their respective parent varieties resulted in the identification of 13 proteins that take part in several processes related to the root hair morphogenesis, such as the control of vesicular trafficking, ROS signalling and homeostasis, signal transduction by phospholipids metabolism and ATP synthesis. Among the identified proteins, two ATP synthases, two ABC transporters, a small GTPase from the SAR1 family, a PDI-like protein, a monodehydroascorbate reductase, a C2 domain-containing protein and a Wali7 domain-containing protein were found. This study is the first report on the proteins identified in the initial stage of root hair formation in barley and gives new insights into the mechanisms of root hair morphogenesis in a monocot species. 相似文献
54.
Zientara M Rudy M Samulska E Partyka M Martirosian G 《Medycyna do?wiadczalna i mikrobiologia》2008,60(1):65-70
Blood cultures (1613) taken from children hospitalized in 13 wards of Upper Silesian Health Center of Child and Mother were studied using Bact/Alert 240 monitoring system (bioMerieux). Around 17.7% of studied cultures were positive: 285 microorganisms were isolated. Gram-positive cocci dominated: 32.3% were strains of MRCNS Gram-negative rods, mainlyEnterobacteriaceae were isolated in 18.6% of cases, non-fermenters--in 12.9%, yeasts (mainly C. albicans)--in 10.5%. More frequently blood cultures were positive in Intensive Care Unit (37.5%). 相似文献
55.
Paweł Mackiewicz Dorota Mackiewicz Agnieszka Gierlik Maria Kowalczuk Aleksandra Nowicka Małgorzata Dudkiewicz Mirosław R. Dudek Stanisław Cebrat 《Journal of molecular evolution》2001,53(6):615-621
We have elaborated a method which has allowed us to estimate the direction of translocation of orthologs which have changed,
during the phylogeny, their positions on chromosome in respect to the leading or lagging role of DNA strands. We have shown
that the relative number of translocations which have switched positions of genes from the leading to the lagging DNA strand
is lower than the number of translocations which have transferred genes from the lagging strand to the leading strand of prokaryotic
genomes. This paradox could be explained by assuming that the stronger mutation pressure and selection after inversion preferentially
eliminate genes transferred from the leading to the lagging DNA strand.
Received: 12 December 2000 / Accepted: 20 April 2001 相似文献
56.
We used a non-invasive TOBEC method (Total Body Electric Conductivity) to estimate lean body mass and fat content in mouse-eared batsMyotis myotis (Borkhausen, 1797) hibernating in Poznañ Forts (W Poland) and in a semi-natural cave-mine Miedzianka (SE Poland). In December, fat content averaged 5.5 g in females (body mass = 29.4 g) and 5.3 g in males (body mass = 28.4 g). At the end of hibernation (April), fat content averaged 2.2 g in females (body mass = 25.6 g) and 1.4 g in males (body mass = 23.7 g). Fat content did not differ between the localities either in December or in April, but the pattern of changes of fat content was different. We calculated the rate of energy expenditure in hibernating bats using two methods, based on independent samples (fat content in first-time captured individuals) and based on paired observations (changes of fat content in re-captured individuals), and discussed problems associated with the two approaches. Both methods show that the bats need about 4.9 g of fat (191 kJ) to sustain a 165-day hibernation. However, the rate of fat usage varied considerably between the sites and hibernation phase. Although the average amount of fat remaining in April would be sufficient to support at least six more weeks of hibernation, the level of reserves was close to zero in some individuals. 相似文献
57.
58.
Andrzej Woznica Agnieszka Nowak Przemyslaw Ziemski Miros?aw Kwasniewski Tytus Bernas 《PloS one》2013,8(1)
Electron transport chain (ETCh) of ammonium (AOB) and nitrite oxidizing bacteria (NOB) participates in oxidation of ammonium to nitrate (nitrification). Operation of ETCh may be perturbed by a range of water-soluble xenobiotics. Therefore, consortia of nitrifying bacteria may be used as a biosensor to detect water contamination. A surprising feature of this system is an increase of oxygen consumption, detected in the presence of certain inhibitors of ETCh. Thus, to shed light on the mechanism of this effect (and other differences between inhibitors) we monitored separately respiration of the bacteria of the first (AOB - Nitrosomonas) and second (NOB -Nitrobacter) stages of nitrification. Furthermore, we measured plasma membrane potential and the level of reduction of NAD(P)H. We propose a novel model of ETCh in NOB to explain the role of reverse electron transport in the stimulation of oxygen consumption (previously attributed to hormesis). 相似文献
59.
60.
The presence of 33 Hyphomycetes species was noted in rainwater falling from six roof types. The following fungi were recorded
for the first time from Poland:Dactylaria lunata, Hyaloscypha zalewskii, Scolecobasidium flagelliferum andWiesneriomyces laurinus. 相似文献