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521.
Allogromiids are organic-walled or agglutinated, single-chambered Foraminifera, common in deep-sea and polar benthic communities. The simple forms and paucity of distinctive features make allogromiid identification difficult by traditional means. Molecular phylogenetic methods offer alternative tools for species identification and are used here to investigate allogromiid diversity. We obtained 135 partial small-subunit ribosomal DNA sequences of allogromiids collected in Explorers Cove, McMurdo Sound, Antarctica. In contrast to the 27 morphotypes identified, phylogenetic analysis revealed 49 molecular types (considered separate species) that differ by more than 5% of sequence divergence. The 49 genetic types form 28 molecular supra-groups that differ by more than 20% and probably represent distinct genera or families. Large genetic distances separating the molecular types indicate unexpectedly high taxonomic diversity. Comparison of our data with sequences of non-Antarctic allogromiids suggests that Explorers Cove species might be endemic and only distantly related to comparable northern hemisphere fauna.  相似文献   
522.
A list of species and the distribution of the members of Plasmopara (Chromista, Peronosporales) on Geranium spp. in the Tatra National Park (Western Carpathians) biospheric reserve are given. Three fungal species parasitizing 3 plant species were recorded in the area. Plasmopara praetermissa is a species new to Poland and Slovakia.  相似文献   
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Bulk-isolated astrocytes from rats with early hepatogenic encephalopathy (HE) induced with thioacetamide responded to the increase of potassium in the incubation medium from 5 mM to 75 mM with a markedly enhanced release of previously taken up [14C]gamma-aminobutyric acid ([14C]GABA). The process was not affected by omission of calcium and/or addition of EGTA to the incubation medium. Only a slight stimulation of GABA release by high potassium was observed in astrocytes from control rats. In contrast, histamine and histidine were vigorously released from control astrocytes in high-potassium medium, and their release was not enhanced by HE, indicating that the observed phenomenon is specific for GABA.  相似文献   
525.
Ardisia crenata Sims (Primulaceae) occurs in natural habitats in two varieties, bearing red or white fruits. While roots of the red-berried ardisia are valued as a medicinal product, the pharmacological activity of which is attributed to triterpene saponins, including ardisiacrispin A, data on the white-berried variety are scarce. A TLC-densitometric method was developed and validated to estimate the levels of saponins, calculated as ardisiacrispin A, in different plant parts in both varieties. Their content amounted to 22.17±4.75 and 25.72±1.46 mg/g d.w. in roots, and 2.64±0.74 and 3.43±0.70 mg/g d.w. in fruits of red-berried and white-berried ardisia, respectively. Assessment of cytotoxicity of ardisiacrispin A and A. crenata extracts on a panel of human cancer cell lines revealed a similar effect of root extracts from both varieties, with the highest potency against melanoma WM793 and colon cancer Caco2. Thus, roots of the white-berried variety may be treated as a substitute for red-berried ardisia and serve as an alternative source for the acquisition of plant material rich in bioactive saponins.  相似文献   
526.
Amino Acids - The circulating amino acid (AAs) concentrations are indicators of dietary protein intake and metabolic status. In celiac disease (CD), the AA imbalance is frequently observed....  相似文献   
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State‐of‐the‐art image‐processing methods offer new possibilities for diagnosing diseases using scattered light. The optical diagnosis of rheumatism is taken as an example to show that the diagnostic sensitivity can be improved using overlapped pseudocolored images of different wavelengths, provided that multispectral images are recorded to compensate for any motion‐related artefacts that occur during examination. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
529.
Bryozoans are among the most important groups of the Southern Ocean benthic macrofauna, both in terms of species richness and abundance. However, there is a considerable lack of ecological research focused on their distribution patterns and species richness on smaller scale, especially in the soft bottom habitats of Antarctic glacial fjords. The aim of this study was to describe those patterns in the Admiralty Bay. Forty-nine Van Veen grab samples were collected at the depth range from 15 to 265 m, in the summer season of 1979/1980, at three sites distributed along the main axis of the fjord. Among 53 identified species of bryozoans, 32 were recorded in the Admiralty Bay for the first time. The most common and abundant species were Himantozoum antarcticum, Inversiula nutrix and Nematoflustra flagellata. Genera such as Arachnopusia, Cellarinella and Osthimosia were the most speciose taxa. It was demonstrated that depth was important for the distribution of the bryozoans. More than half of the recorded species were found only below 70 m. An influence of glacial disturbance was reflected in the dominance structure of colony growth-forms. The inner region of the fjord was dominated almost entirely by encrusting species, while the diversity of bryozoan growth-forms in less disturbed areas was much higher. In those sites the highest percentage of branched, tuft like species represented by buguliform and flustriform zoaria was observed.  相似文献   
530.
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