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61.
Epidemic hemorrhagic fever in Hubei Province, The People's Republic of China: a clinical and serological study 总被引:1,自引:0,他引:1
M S Cohen J Casals G D Hsiung H E Kwei C C Chin H C Ge C M Hsiang P W Lee C J Gibbs D C Gajdusek 《The Yale journal of biology and medicine》1981,54(1):41-55
Between July 1975 and April 1980, 71 patients were admitted to the Second Attached Hospital of Hubei Provincial Medical College in Wuchang with the diagnosis of epidemic hemorrhagic fever (EHF). The clinical course among these patients was similar to that described for patients with Korean hemorrhagic fever, and hemorrhagic fever with renal syndrome of the U.S.S.R. The overall mortality was 11.2 percent. Sera obtained from some of these patients as well as from patients admitted to the First Attached Hospital of Hubei Provincial Medical College were tested against an antigen associated with Korean hemorrhagic fever and showed exceedingly high antibody titers. We conclude that EHF in Central China represents the same or a closely related disease process as Korean hemorrhagic fever. 相似文献
62.
Aims
Shrub encroachment in mesic grasslands alters the identity and quality of litters entering the system. As litter from shrubs and grasses can differ in their quality, this can lead to differences in litter decomposition by the direct effect of quality, but also to litter interaction during decomposition. The objective of this study was to examine the occurrence of non-additive effects of litter mixtures on the decomposition rates of legume shrub litter (poor in P) or conifer shrub litter (poor in N) and grass litter.Methods
In addition to single litter type litterbags for the three species, we mixed litters of each pair of possible combinations to determine the influence of each species on mass loss. Litterbags were placed in the field and collected after 1, 6, 8, 12 and 24 months. In each collection, litter of each species remaining in mixed bags was separated, dry weighed and analyzed for C, N and P.Results
With respect to shrub litter decomposing alone, mass loss of shrub litter when mixed with grass showed a 9–10 % increase in decomposition rate for conifer and a 3 % increase for legume litter. These litter mixture effects varied with time and they were detected after a decomposition period of 1 year in legume litter and of 2 years in conifer litter.Conclusions
Grass litter hastened conifer and legume litter decomposition in leaf litter mixtures, at least during the first stages of the process. The potential consequences of this result to alter litter accumulation patterns and thus carbon sequestration rates after shrub encroachment into grasslands will depend on whether the observed trends are maintained in the advanced decomposition stages. 相似文献63.
64.
Carles Ibáñez Nuno Caiola José Barquín Oscar Belmar Xavier Benito-Granell Frederic Casals Siobhan Fennessy Jocelyne Hughes Margaret Palmer Josep Peñuelas Estela Romero Jordi Sardans Michael Williams 《Global Change Biology》2023,29(5):1248-1266
Trends and ecological consequences of phosphorus (P) decline and increasing nitrogen (N) to phosphorus (N:P) ratios in rivers and estuaries are reviewed and discussed. Results suggest that re-oligotrophication is a dominant trend in rivers and estuaries of high-income countries in the last two–three decades, while in low-income countries widespread eutrophication occurs. The decline in P is well documented in hundreds of rivers of United States and the European Union, but the biotic response of rivers and estuaries besides phytoplankton decline such as trends in phytoplankton composition, changes in primary production, ecosystem shifts, cascading effects, changes in ecosystem metabolism, etc., have not been sufficiently monitored and investigated, neither the effects of N:P imbalance. N:P imbalance has significant ecological effects that need to be further investigated. There is a growing number of cases in which phytoplankton biomass have been shown to decrease due to re-oligotrophication, but the potential regime shift from phytoplankton to macrophyte dominance described in shallow lakes has been documented only in a few rivers and estuaries yet. The main reasons why regime shifts are rarely described in rivers and estuaries are, from one hand the scarcity of data on macrophyte cover trends, and from the other hand physical factors such as peak flows or high turbidity that could prevent a general spread of submerged macrophytes as observed in shallow lakes. Moreover, re-oligotrophication effects on rivers may be different compared to lakes (e.g., lower dominance of macrophytes) or estuaries (e.g., limitation of primary production by N instead of P) or may be dependent on river/estuary type. We conclude that river and estuary re-oligotrophication effects are complex, diverse and still little known, and in some cases are equivalent to those described in shallow lakes, but the regime shift is more likely to occur in mid to high-order rivers and shallow estuaries. 相似文献
65.
66.
Mouse interferon was obtained in relatively large volumes by the use of ascitic fluid from mice bearing sarcoma 180/TG and subsequently inoculated with Germiston virus. 相似文献
67.
Nunes V. Casals T. Gallano P. Giménez F. J. Kere J. Williamson R. Estivill X. 《Human genetics》1989,83(3):305-306
Summary We report a rare allele detected using pMP6d-9, a probe very closely linked to cystic fibrosis (CF), on digestion with MspI. This allele has been found in normal and CF chromosomes, and therefore cannot be related to the mutation causing the disease. 相似文献
68.
Cruz A Worthman LA Serrano AG Casals C Keough KM Pérez-Gil J 《European biophysics journal : EBJ》2000,29(3):204-213
Suspensions of dipalmitoylphosphatidylcholine (DPPC) bilayers containing 5, 10 or 20% (w/w) surfactant protein SP-B have
been reconstituted and spread at air-liquid interfaces. Compression isotherms of DPPC/SP-B monolayers spread from these preparations
were qualitatively comparable to the isotherms of the corresponding DPPC/SP-B monolayers spread from solvents. SP-B was squeezed-out
at higher pressures from vesicle-spread films than from solvent-spread monolayers. SP-B caused a marked decrease on the rate
of relaxation of DPPC collapse phases to equilibrium pressures in all the lipid/protein films assayed. This stabilizing effect
was higher in vesicle-spread than in solvent-spread monolayers. Inclusion in the films of traces of the fluorescent probe
NBD-PC (1 mol%) and use of a fluorescent derivative of SP-B labeled with a rhodamine derivative, Texas Red, allowed for direct
observation of protein and lipid domains at the interface by epifluorescence microscopy. Upon compression, SP-B altered the
packing of phospholipids in the bilayer-spread films, observed as a SP-B-induced reduction of the area of liquid-condensed
domains, in a way similar to its effect in solvent-spread monolayers. SP-B was not associated with condensed regions of the
films. Fluorescence images from vesicle-spread films showed discrete fluorescent aggregates that could be consistent with
the existence of lipid-protein vesicles in close association with the monolayer. Both the retention of SP-B at higher surface
pressures and the greater stability of collapse phases of DPPC/SP-B films prepared by spreading from liposomes in comparison
to those spread from solvents can be interpreted as a consequence of formation of complex bilayer-monolayer interacting systems.
Received: 1 December 1999 / Revised version: 2 March 2000 / Accepted: 2 March 2000 相似文献
69.
Modification of pyruvate kinase isozymes in prolonged primary cultures of adult rat hepatocytes. 总被引:2,自引:0,他引:2
Pyruvate kinase isozymic changes were studied in the adult hepatocyte cultures, by electrophoretic, kinetic and immunological methods. We were able to maintain parenchymal cells from normal adult rat liver in non-proliferating monolayer cultures up to 10 days. Hepatocytes appeared to contain a dominant PK I type up to 4-5 days of culture. After day 5, PK III type was regularly present with PK I and after 7 days PK III type was always the only isozyme detected in culture. It must be pointed out that, by the Ouchterlony method and sometimes by electrophoresis, concentrated extracts from freshly isolated hepatocytes or starting hepatocyte cultures did also contain Pyruvate kinase PK III type. These results suggest that Pyruvate kinase III is present but partly repressed in the adult parenchymal cells and becomes derepressed in culture. 相似文献
70.