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Anaerobic enrichment culture with thiocyanate as electron donor and nitrate as electron acceptor at 2 M NaCl inoculated with a mixture of sediments from hypersaline lakes in Kulunda Steppe (Altai, Russia) resulted in a selection of a binary consortium of moderately halophilic, obligately chemolithoautotrophic sulfur-oxidizing bacteria (SOB) capable of complete denitrification of nitrate with thiosulfate as the electron donor. One consortium member, strain HRhD 3sp, was isolated into pure culture with nitrate and thiosulfate using a density gradient. This strain was responsible for the reduction of nitrate to nitrite in the consortium, while a second strain, HRhD 2, isolated under microoxic conditions with thiosulfate as substrate, was capable of anaerobic growth with nitrite and thiosulfate. Nitrite, either as substrate or as product, was already toxic at very low concentrations for both strains. As a result, optimal growth under anaerobic conditions could only be achieved within the consortium. On the basis of phylogenetic analysis, both organisms were identified as new lineages within the Gammaproteobacteria. As well as thiosulfate, strain HRhD 2 can also use thiocyanate as electron donor, representing a first halophilic SOB capable of growth with thiocyanate at 2–4 M NaCl. Product and enzymatic analysis identified the “carbonyl sulfide (COS) pathway” of primary thiocyanate degradation in this new species. On the basis of phenotypic and genetic analysis, strain HRhD 2 is proposed to be assigned to a new genus and species Thiohalophilus thiocyanoxidans. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

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To assess whether physicians, residents, medical students, hospital diagnosis coders, and patients properly use the designations insulin-dependent diabetes mellitus (IDDM) and non-insulin-dependent diabetes mellitus (NIDDM) that were established by criteria of the National Diabetes Data Group, we reviewed clinic and hospital records and administered questionnaires. Although essentially all cases of true IDDM were identified as such and most cases of NIDDM not requiring insulin therapy were correctly identified by all groups, patients with NIDDM on insulin therapy were misidentified as having IDDM by 38% of residents in internal medicine clinics and 68% of primary care and surgical subspecialty residents. On a survey, of 22 patients with NIDDM on insulin therapy, 17 (77%) considered themselves to have IDDM. Thus, patients who have NIDDM by the established criteria who are on insulin therapy are commonly mislabeled as having IDDM. We present an approach for dealing with this problem by adapting nomenclature focusing on insulin deficiency and resistance. It would probably also be helpful to separately identify the subset of patients with "insulin-deficient diabetes" who are ketosis-prone. It is important to use immunologic profiling (islet cell antibody testing) and insulin sensitivity or deficiency testing (C-peptide levels).  相似文献   

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Åke Hullkrantz 《Ethnos》2013,78(1-4):170-178
Prelude to East African History, a collection of papers given at the First East African Vacation School in Pre‐European African History and Archaeology in December 1962, Merrick Posnansky, editor, Student's Library, Oxford University Press, London 1966. 186 pp., 9 s. 6 d.

Ethiopian Music. An Introduction. A Survey of Ecclesiastical and Secular Ethiopian Music and Instruments. Michael Powne. Oxford University Press, London 1966. xix+160 pp., 11 pl., 5 figs., 36 music ex. 1 map. Price 42 s. ‐ 2nd edition. London 1968. Price 45 s.

An Africans Religion. The Spirit of Nyajena. Case History of a Karanga People. Michael Gelfand. Juta &; Co., Limited. Cape Town, Wynberg, Johannesburg 1966. 135 pp. 1 Karte, Illustr. Price 37 s 6 d.

Mkhas Grub Rje's Fundamentals of the Buddhist Tantras. Ferdinand D. Lessing and Alex Wayman. Rgyud sde spyihi rnam par gzag pa rgyas par brjod. The Hague, Paris. 1968.

A Ceremonial Ox of India: The Mithan in Nature, Culture, and History. Frederick J. Simoons. University of Wisconsin Press Ltd., London 1968. 323 pp., pr. 104 s. 6 d.

Dor el Gussa und Gebel ben Ghnema. Zur nachpluvialen Besiedlungsgeschichte des Ostfezzan. Ergebnisse der Frobenius‐Expedition nach libyen 1963/64. Helmut Ziegert. Veröffentlichung des Frobenius‐Institutes Frankfurt. F. Steiner Verlag. Wiesbaden 1967. X+94 S. m. 19 Abb., 203 Taf., 3 Karten. Gebunden. DM 66: ‐.

Archäologische Untersuchungen am Mittleren Amazonas. Beiträge zur Vorgeschichte des südamerikanischen Tieflandes. Peter Paul Hilbert. Marburger Studien zur Völkerkunde I. Dietrich Reimer Verlag, Berlin 1968. 164 Abb., 11 Karten, 337 Seiten. Preis DM 60:‐.

Bibliography of Benin Art. Paula Ben‐Amos. Primitive Art Bibliographies. No. VI. The Museum of Primitive Art. New York 1968, 27 pp.

Anthropological Approaches to the Study of Religion. 1966. 176 pp. Price 30 s.

The Social Anthropology of Complex Societies. 1966. 156 pp. Price 30 s. A.S.A. Monographs 3 and 4. Michael Banton (general editor). Tavistock Publications. London.

Case Studies in Cultural Anthropology. George and Louise Spindler (general editors). Holt, Rinehart and Winston, Inc., New York, Chicago, San Francisco, Toronto, London.

Changing Japan. Edward Norbeck. 1965. 82 pp., 1 map, 1 pl.

The Dusun. A North Borneo Society. Thomas Rhys Williams. 1965. 100 pp., 1 pl., 1 map.

Understanding an African Kingdom: Bunyoro. John Beatty. New York … 1965. 61 pp., 1 map.

Bunyoro. An African Kingdom. John Beatty. New York … 1960. 86 pp., 1 pl., 1 map.  相似文献   

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The individual influence of sulfate reducing and brown phototrophic sulfur bacteria from Lake Kinneret on the metalimnetic redox conditions was investigated by simulating the hydrochemical and microbiological conditions in a specially designed chemostat. The results show a strong correlation between measured redox values and the prevailing hydrogen sulfide concentration leading to a linear relationship. Changes in this relationship allowed differentiation between the on-going microbial processes, sulfate reduction and sulfide oxidation. The comparison ofin vitro andin situ redox values shows that the results of the simulation experiments agree with the data previously measured in the metalimnion of Lake Kinneret.  相似文献   

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Palaeobotanical analysis and radiocarbon dating of lake sediments from Bachalpsee (2265 m a.s.l.), a small lake above the present-day timber-line in the northern Swiss Alps reveals that the region was already deglaciated during the Younger Dryas. The sediment record is dominated by long-distance transported pollen that originates from lowland vegetation but the plant macrofossils give evidence of the local vegetation development. Comparison with palaeobotanical results from three sites along an altitudinal transect permits the reconstruction of the regional timber-line history. Throughout the entire Holocene the catchment of Bachalpsee consisted of a mosaic of open meadows and dwarf shrubs (Salix, Vaccinium, Rhododendron). Chironomid and cladoceran assemblages suggest that the early to mid-Holocene was the warmest interval at Bachalpsee. Comparison of the palaeobotanical results with those from the mire “Feld” (2130 m a.s.l.) in the vicinity of Bachalpsee showed that during the mid-Holocene the timber-line was formed by Pinus cembra and Picea abies with some scattered Abies alba trees and was situated close to Bachalpsee but never reached its catchment. The maximum timber-line in the Northern Alps was reached between 6000 and 3000 cal b.p. which is several millennia later than in the Central Alps. The species composition of the tree-line (Abies alba, Pinus cembra and the absence of Larix decidua) points to less continental and moister climatic conditions compared with the central Alps during the early to mid-Holocene. From 3000 cal b.p. onwards the timber-line was lowered by human deforestation with the most intense pulses of human impact occurring since the Middle Ages. The catchment of Bachalpsee has been used as alpine pasture since the Bronze Age.  相似文献   

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We aim to provide a long-term ecological analysis of land-use and floristic diversity in the transition from traditional to modern land-use management in the time a.d. 1800–2008 in southern Sweden. We use the Regional Estimates of Vegetation Abundance from Large Sites (REVEALS) model to quantify land-cover changes on a regional scale at 20-year intervals, based on the fossil pollen record. Floristic richness and evenness are estimated using palynological richness and the Shannon index applied to the REVEALS output, respectively. We identified a transition period of 60?years between 1880 and 1940 when the total tree cover increased and the tree composition changed from deciduous to coniferous dominance. Within the shrinking area of open land, arable land taxa expanded, while the number and coverage of herbs in the remaining grasslands decreased. The succession from open grasslands to more tree-covered habitats initially favoured palynological richness, which reached its highest values during the first 40?years of the transition period. The highest REVEALS-based evenness was recorded in the time of traditional land-use and at the beginning of the transition period, reflecting higher habitat diversity at these time intervals. Our results support a more dynamic ecosystem management that changes between traditional land-use and phases of succession (<40?years) to promote floristic diversity. We have developed and applied a palaeoecological methodology that contributes realistic estimates to be used in ecosystem management.  相似文献   

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In the U.S. multidisciplinary pediatric pain clinic where I conducted 18 months of fieldwork, a widely held explanatory model tied the neurobiology of intractable pain to certain features of pervasive developmental disorders (PDD) such as concrete thinking, an interest in details, and hyper-attentiveness. Clinicians used terms such as “sticky brains” and “sticky neurons” to describe the perseverative thoughts and quirky behavior that characterized a sizable subset of the program’s chronic pain patients who were believed to show signs of PDD, and consequently, did not respond well to treatment. Drawing on observations of clinical consultations, team meetings, and interviews with clinicians and families, I examine the meta-discursive processes by which clinical difficulties were inscribed onto difficult patients. Specifically, I demonstrate how discourse on sticky brains worked to re-classify challenging patients as psychologically abnormal, rationalizing their failed response to standard treatment. I argue that ‘stickiness’ provides an appropriate metaphor not only for a particular neurobiological configuration, but also for challenging clinical encounters. By illuminating the interactional processes through which clinical difficulties are managed, interpreted, and explained, the paper advances anthropological theorizing on the performative work of diagnosis and institutionalized misrecognition.  相似文献   

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Summary Oögenesis in the oviparous marine teleost, Blennius pholis L., is examined. Eleven developmental stages are identified by ultrastructural observations when changes in the distributions of the organelles and inclusions are described. An exogenous source for the protein yolk precursors is indicated, but less clear is the endogenous contribution. Changes in the follicle epithelium are described together with the formation of the zona which is considered to be follicular in origin. Two types of follicle cell are distinguished and these probably function differently in the process of zona formation. The zona becomes divided into the externa and interna, the latter probably resulting from the chemical ordering by disulphide bonding of the proteinaceous material of the former.We are indebted to Professor E.W. Knight-Jones in whose department the work was carried out, and to the Natural Environment Research Council for support for one of us (S.E.S.).  相似文献   

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Central nervous system (CNS) stem cells have become the subject of many laboratories' efforts, presentations, and publications. Yet, in the stem cell world, CNS cells are viewed with skepticism. This is likely due to a dearth of biology (in vivo function) to accompany a flurry of phenomenological and restorative neurology studies. In this article, we compare and contrast the biological knowledge of adult forebrain epidermal growth factor-responsive neural stem cells that has emerged from our laboratories with that of hematopoietic stem cells, using two recent papers in the latter field as specific examples. A comparison of stem cell location, lineage, and repopulation suggests that our understanding of CNS stem cell biology is immature. We conclude that a greater focus on in vivo biology will enhance our knowledge and understanding of CNS stem cells. © 1998 John Wiley & Sons, Inc. J Neurobiol 36: 307–314, 1998  相似文献   

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K. S. Unni  S. Pawar 《Hydrobiologia》2000,430(1-3):87-96
Phytoplankton of the River Seonath, a major tributary of Mahanadi river system, was studied for 15 months together with physical–chemical variables in relation to a pollution gradient. Multivariate analysis and ordination by Principal Components Analysis of the physical–chemical variables and phytoplankton density indicated a community replacement along a pollution gradient. The dominant benthic diatom community, mainly comprising Achnanthes trigibba and A. affinis of the upstream was replaced by Chlorophycea at the middle stretch and Cyanophycea at the downstream sites. Chlorella, Scenedesmus and Coelastrum dominated among Chlorophyceae in the middle stretch in the highly polluted sites, followed by the Cyanophycean assemblage of Microcystis and Merismopedia.  相似文献   

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Grigorszky  I.  Padisák  J.  Borics  G.  Schitchen  C.  Borbély  G. 《Hydrobiologia》2003,506(1-3):209-212
Hydrobiologia - The stability of the water column permitted stable stratification of the shallow (maximum depth: 3.75 m) oxbow, Kecskészugi-Holt Körös in summer 2000. During the...  相似文献   

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Randomly amplified polymorphic DNA (RAPD) analysis was used to investigate the genetic variation among populations, between populations, and within populations, relationships between genetic distance and geographic distance, and the molecular variation and population size. The effects of geographic and genetic distances, as well as of genetic differentiation and population size, on genetic variations of Leymus chinensis (Trin.) Tzvel. are discussed. The present study showed that there was significant RAPD variation between the Baicheng region population and the Daqing region population, with a molecular variance of 6.35% (P 〈 0.04), and for differentiation among area populations of the Daqing region, with a molecular variance of 8.78% (P 〈 0.002). A 21.06% RAPD variation among all 16 populations among two regions was found (P 〈 0.001), as well as 72.59% variation within populations (P 〈 0.001). Molecular variation within populations was significantly different among 16 populations.  相似文献   

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Pavlov's concept of conditioned reflexes and Ukhtomskii theory of dominanta fall within the biological line in physiology. They unravel the integral adaptive and active nature of the organism behavior in the environment. It is impossible to develop modern concepts about the determinants of goal-directed behavior of animals and voluntary activity of humans without in-depth study of the achievements of these Russian physiological schools which not only formed the methodological basis for the current studies but also directed the way for their further development.  相似文献   

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