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151.
152.
Kjellman BM Fredrikson M Glad-Mattsson G Sjöberg F Huss FR 《Annals of surgical innovation and research》2011,5(1):4-8
Background
Hypothermia in burns is common and increases morbidity and mortality. Several methods are available to reach and maintain normal core body temperature, but have not yet been evaluated in critical care for burned patients. Our unit's ordinary technique for controlling body temperature (Bair Hugger®+ radiator ceiling + bed warmer + Hotline®) has many drawbacks e.g.; slow and the working environment is hampered. The aim of this study was to compare our ordinary heating technique with newly-developed methods: the Allon?2001 Thermowrap (a temperature regulating water-mattress), and Warmcloud (a temperature regulating air-mattress).Methods
Ten consecutive burned patients (> 20% total burned surface area and a core temperature < 36.0°C) were included in this prospective, randomised, comparative study. Patients were randomly exposed to 3 heating methods. Each treatment/measuring-cycle lasted for 6 hours. Each heating method was assessed for 2 hours according to a randomised timetable. Core temperature was measured using an indwelling (bladder) thermistor. Paired t-tests were used to assess the significance of differences between the treatments within the patients. ANOVA was used to assess the differences in temperature from the first to the last measurement among all treatments. Three-way ANOVA with the Tukey HSD post hoc test and a repeated measures ANOVA was used in the same manner, but included information about patients and treatment/measuring-cycles to control for potential confounding. Data are presented as mean (SD) and (range). Probabilities of less than 0.05 were accepted as significant.Results
The mean increase, 1.4 (SD 0.6°C; range 0.6-2.6°C) in core temperature/treatment/measuring-cycle highly significantly favoured the Allon?2001 Thermowrap in contrast to the conventional method 0.2 (0.6)°C (range -1.2 to 1.5°C) and the Warmcloud 0.3 (0.4)°C (range -0.4 to 0.9°C). The procedures for using the Allon?2001 Thermowrap were experienced to be more comfortable and straightforward than the conventional method or the Warmcloud.Conclusions
The Allon?2001 Thermowrap was more effective than the Warmcloud or the conventional method in controlling patients' temperatures. 相似文献153.
Molecular heterogeneity of RET loss of function in Hirschsprung's disease. 总被引:7,自引:0,他引:7
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F Carlomagno G De Vita M T Berlingieri V de Franciscis R M Melillo V Colantuoni M H Kraus P P Di Fiore A Fusco M Santoro 《The EMBO journal》1996,15(11):2717-2725
The RET proto-oncogene encodes a receptor with tyrosine kinase activity (RET) that is involved in several neoplastic and non-neoplastic diseases. Oncogenic activation of RET, achieved by different mechanisms, is detected in a sizeable fraction of human thyroid tumors, as well as in multiple endocrine neoplasia types 2A and 2B (MEN2A and MEN2B) and familial medullary thyroid carcinoma tumoral syndromes. Germline mutations of RET have also been associated with a non-neoplastic disease, the congenital colonic aganglionosis, i.e. Hirschsprung's disease (HSCR). To analyse the impact of HSCR mutations on RET function, we have introduced into wild-type RET and activated RET(MEN2A) and RET(MEN2B) alleles three missense mutations associated with HSCR. Here we show that the three mutations caused a loss of function of RET when assayed in two model cell systems, NIH 3T3 and PC12 cells. The effect of different HSCR mutations was due to different molecular mechanisms. The HSCR972 (Arg972-->Gly) mutation, mapping in the intracytoplasmic region of RET, impaired its tyrosine kinase activity, while two extracellular mutations, HSCR32 (Ser32-->Leu) and HSCR393 (Phe393-->Leu), inhibited the biological activity of RET by impairing the correct maturation of the RET protein and its transport to the cell surface. 相似文献
154.
One of the limitations of the use of phage antibody libraries in high throughput selections is the production of sufficient phage antibody library at the appropriate quality. Here, we successfully adapt a bioreactor-based protocol for the production of phage peptide libraries to the production of phage antibody libraries. The titers obtained in the stirred-tank bioreactor are 4 to 5 times higher than in a standard shake flask procedure, and the quality of the phage antibody library produced is indistinguishable to that produced using standard procedures as assessed by Western blotting and functional selections. Availability of this protocol will facilitate the use of phage antibody libraries in high-throughput scale selections. 相似文献
155.
D Deprez J Fransen M Lenoir RM Philippaerts R Vaeyens 《Biology of sport / Institute of Sport》2015,32(1):65-70
The aim of the study was to investigate test reliability of the Yo-Yo intermittent recovery test level 1 (YYIR1) in 36 high-level youth soccer players, aged between 13 and 18 years. Players were divided into three age groups (U15, U17 and U19) and completed three YYIR1 in three consecutive weeks. Pairwise comparisons were used to investigate test reliability (for distances and heart rate responses) using technical error (TE), coefficient of variation (CV), intra-class correlation (ICC) and limits of agreement (LOA) with Bland-Altman plots. The mean YYIR1 distances for the U15, U17 and U19 groups were 2024 ± 470 m, 2404 ± 347 m and 2547 ± 337 m, respectively. The results revealed that the TEs varied between 74 and 172 m, CVs between 3.0 and 7.5%, and ICCs between 0.87 and 0.95 across all age groups for the YYIR1 distance. For heart rate responses, the TEs varied between 1 and 6 bpm, CVs between 0.7 and 4.8%, and ICCs between 0.73 and 0.97. The small ratio LOA revealed that any two YYIR1 performances in one week will not differ by more than 9 to 28% due to measurement error. In summary, the YYIR1 performance and the physiological responses have proven to be highly reliable in a sample of Belgian high-level youth soccer players, aged between 13 and 18 years. The demonstrated high level of intermittent endurance capacity in all age groups may be used for comparison of other prospective young soccer players. 相似文献
156.
Alison H. Magill John D. Aber Glenn M. Berntson William H. McDowell Knute J. Nadelhoffer Jerry M. Melillo Paul Steudler 《Ecosystems》2000,3(3):238-253
This article reports responses of two different forest ecosystems to 9 years (1988–96) of chronic nitrogen (N) additions
at the Harvard Forest, Petersham, Massachusetts. Ammonium nitrate (NH4NO3) was applied to a pine plantation and a native deciduous broad-leaved (hardwood) forest in six equal monthly doses (May–September)
at four rates: control (no fertilizer addition), low N (5 g N m-2 y-1), high N (15 g N m-2
y-1), and low N + sulfur (5 g N m-2 y-1 plus 7.4 g S m-2 y-1). Measurements were made of net N mineralization, net nitrification, N retention, wood production, foliar N content and litter
production, soil C and N content, and concentrations of dissolved organic carbon (DOC) and nitrogen (DON) in soil water. In
the pine stand, nitrate losses were measured after the first year of additions (1989) in the high N plot and increased again
in 1995 and 1996. The hardwood stand showed no significant increases in nitrate leaching until 1995 (high N only), with further
increases in 1996. Overall N retention efficiency (percentage of added N retained) over the 9-year period was 97–100% in the
control and low N plots of both stands, 96% in the hardwood high N plot, and 85% in the pine high N plot. Storage in aboveground
biomass, fine roots, and soil extractable pools accounted for only 16–32% of the added N retained in the amended plots, suggesting
that the one major unmeasured pool, soil organic matter, contains the remaining 68–84%. Short-term redistribution of 15N tracer at natural abundance levels showed similar division between plant and soil pools. Direct measurements of changes
in total soil C and N pools were inconclusive due to high variation in both stands. Woody biomass production increased in
the hardwood high N plot but was significantly reduced in the pine high N plot, relative to controls. A drought-induced increase
in foliar litterfall in the pine stand in 1995 is one possible factor leading to a measured increase in N mineralization,
nitrification, and nitrate loss in the pine high N plot in 1996.
Received 2 April 1999; Accepted 29 October 1999. 相似文献
157.
Using inbreeding theory as applied to neutral alleles inherited maternally,
we generate expected probability distributions of times to identity by
descent for random pairs of mitochondrial genotypes within a population or
within an entire species characterized by high gene flow. For comparisons
with these expectations, empirical distributions of times to most recent
common ancestry were calculated (by conventional mtDNA clock calibrations)
from mtDNA haplotype distances observed within each of three vertebrate
species--American eels, hardhead catfish, and redwinged blackbirds. These
species were chosen for analysis because census population size in each is
currently large and because both genetic and life-history data are
consistent with the postulate that historical gene flow within these
species has been high. The observed molecular distances among mtDNA
lineages were two to three orders of magnitude lower than predicted from
census sizes of breeding females, suggesting that rate of mtDNA evolution
is decelerated in these species and/or that long-term effective population
size is vastly smaller than present-day population size. Several
considerations point to the latter possibility as most likely. The genetic
structure of any species is greatly influenced by historical demography;
even for species that are currently abundant, mtDNA gene lineages appear to
have been channeled through fairly small numbers of ancestors.
相似文献
158.
Yude Pan Jerry M. Melillo A. David McGuire David W. Kicklighter Louis F. Pitelka Kathy Hibbard Lars L. Pierce Steven W. Running Dennis S. Ojima William J. Parton David S. Schimel 《Oecologia》1998,114(3):389-404
Although there is a great deal of information concerning responses to increases in atmospheric CO2 at the tissue and plant levels, there are substantially fewer studies that have investigated ecosystem-level responses in
the context of integrated carbon, water, and nutrient cycles. Because our understanding of ecosystem responses to elevated
CO2 is incomplete, modeling is a tool that can be used to investigate the role of plant and soil interactions in the response
of terrestrial ecosystems to elevated CO2. In this study, we analyze the responses of net primary production (NPP) to doubled CO2 from 355 to 710 ppmv among three biogeochemistry models in the Vegetation/Ecosystem Modeling and Analysis Project (VEMAP):
BIOME-BGC (BioGeochemical Cycles), Century, and the Terrestrial Ecosystem Model (TEM). For the conterminous United States,
doubled atmospheric CO2 causes NPP to increase by 5% in Century, 8% in TEM, and 11% in BIOME-BGC. Multiple regression analyses between the NPP response
to doubled CO2 and the mean annual temperature and annual precipitation of biomes or grid cells indicate that there are negative relationships
between precipitation and the response of NPP to doubled CO2 for all three models. In contrast, there are different relationships between temperature and the response of NPP to doubled
CO2 for the three models: there is a negative relationship in the responses of BIOME-BGC, no relationship in the responses of
Century, and a positive relationship in the responses of TEM. In BIOME-BGC, the NPP response to doubled CO2 is controlled by the change in transpiration associated with reduced leaf conductance to water vapor. This change affects
soil water, then leaf area development and, finally, NPP. In Century, the response of NPP to doubled CO2 is controlled by changes in decomposition rates associated with increased soil moisture that results from reduced evapotranspiration.
This change affects nitrogen availability for plants, which influences NPP. In TEM, the NPP response to doubled CO2 is controlled by increased carboxylation which is modified by canopy conductance and the degree to which nitrogen constraints
cause down-regulation of photosynthesis. The implementation of these different mechanisms has consequences for the spatial
pattern of NPP responses, and represents, in part, conceptual uncertainty about controls over NPP responses. Progress in reducing
these uncertainties requires research focused at the ecosystem level to understand how interactions between the carbon, nitrogen,
and water cycles influence the response of NPP to elevated atmospheric CO2.
Received: 13 December 1996 / Accepted: 20 November 1997 相似文献
159.
Guillain-Barré syndrome is the most common polyneuropathy causing major disability and respiratory failure. Respiratory complications are the main cause of death. Improved respiratory care and new treatment strategies such as plasmaphoresis and immunoglobulin have been shown to improve outcome. We studied the course and outcome of 37 patients with Guillain-Barré syndrome who were admitted to a rehabilitation and respiratory care facility over a 10-year period. There were 21 males and 16 females with a mean age of 62+/-3 years. Fourteen patients developed respiratory failure requiring endotracheal intubation and mechanical ventilation. The mean duration of mechanical ventilation was 38+/-10 days. All patients were successfully liberated from the ventilator. However, 83 percent of the patients were moderately to severely disabled at the time of discharge. Thirteen out of 37 (35 percent) developed long-term disability. None of the patients died over the period of follow-up. These results indicate that early recognition and treatment of respiratory complications in Guillain-Barré syndrome could reduce the morbidity and mortality of this condition. 相似文献
160.
Developmental and wound-, cold-, desiccation-, ultraviolet-B-stress-induced modulations in the expression of the petunia zinc finger transcription factor gene ZPT2-2
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van Der Krol AR van Poecke RM Vorst OF Voogt C van Leeuwen W Borst-Vrensen TW Takatsuji H van Der Plas LH 《Plant physiology》1999,121(4):1153-1162
The ZPT2-2 gene belongs to the EPF gene family in petunia (Petunia hybrida), which encodes proteins with TFIIIA-type zinc-finger DNA-binding motifs. To elucidate a possible function for ZPT2-2, we analyzed its pattern of expression in relation to different developmental and physiological stress signals. The activity of the ZPT2-2 promoter was analyzed using a firefly luciferase (LUC) reporter gene, allowing for continuous measurements of transgene activity in planta. We show that ZPT2-2::LUC is active in all plant tissues, but is strongly modulated in cotyledons upon germination, in leaves in response to desiccation, cold treatment, wounding, or ultraviolet-B light, and in petal tissue in response to pollination of the stigma. Analysis of mRNA levels indicated that the modulations in ZPT2-2::LUC expression reflect modulations in endogenous ZPT2-2 gene expression. The change in ZPT2-2::LUC activity by cold treatment, wounding, desiccation, and ultraviolet-B light suggest that the phytohormones ethylene and jasmonic acid are involved in regulating the expression of ZPT2-2. Although up-regulation of expression of ZPT2-2 can be blocked by inhibitors of ethylene perception, expression in plants is not induced by exogenously applied ethylene. The application of jasmonic acid does result in an up-regulation of gene activity and, thus, ZPT2-2 may play a role in the realization of the jasmonic acid hormonal responses in petunia. 相似文献