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401.
Wether lambs were fed on precision-chopped first-cut ryegrass silage ad libitum in an intake trial, and a maintenance and 1.5 times maintenance in balance trials.The untreated and treated silages had pH values of 4.72 and 4.40, mean dry matter (DM) contents of 176 and 184 g kg?1 and mean gross energy (GE) contents of 18.8 and 19.0 MJ/kg DM, respectively.Mean digestibility coefficients of DM (0.787 and 0.783), organic matter (OM) (0.827 and 0.820) and GE (0.794 and 0.793), for the treated and untreated silages respectively, were high. The metabolisable energy (ME) contents of the untreated and treated silages were 12.52 and 12.76 MJ/kg DM at maintenance and 11.94 and 12.56 MJ/kg DM at 1.5 times maintenance, respectively. The mean efficiency of utilisation of ME of the untreated and treated silages was 0.65 and 0.66 for maintenance (km) and 0.34 ± 0.134 and 0.40 ± 0.069 for growth (kg), respectively; the kg values were lower than expected.Dry matter intakes of these silages when given ad libitum were 27.9 and 28.8 g/kg W per day and produced live weight gains of 129 and 140 g day?1 for the untreated and treated silages, respectively. These gains were similar to predicted values for live weight gain only when the experimentally determined kg and km values were substituted in the equation of the Agricultural Research Council (1980) used for calculating the daily metabolisable energy requirements for live weight gain. 相似文献
402.
Screening pentachlorophenol degradation ability by environmental fungal strains belonging to the phyla Ascomycota and Zygomycota 总被引:1,自引:0,他引:1
Mariana B. Carvalho Isabel Martins Maria C. Leitão Helga Garcia Cátia Rodrigues Vitória San Romão Iain McLellan Andrew Hursthouse Cristina Silva Pereira 《Journal of industrial microbiology & biotechnology》2009,36(10):1249-1256
Pentachlorophenol (PCP) bioremediation by the fungal strains amongst the cork-colonising community has not yet been analysed.
In this paper, the co- and direct metabolism of PCP by each of the 17 fungal species selected from this community were studied.
Using hierarchical data analysis, the isolates were ranked by their PCP bioremediation potential. Fifteen isolates were able
to degrade PCP under co-metabolic conditions, and surprisingly Chrysonilia sitophila, Trichoderma longibrachiatum, Mucor plumbeus, Penicillium janczewskii and P. glandicola were able to directly metabolise PCP, leading to its complete depletion from media. PCP degradation intermediates are preliminarily
discussed. Data emphasise the significance of these fungi to have an interesting potential to be used in PCP bioremediation
processes. 相似文献
403.
Assignment of uroporphyrinogen decarboxylase (UROD) to the pter----p21 region of human chromosome 1 总被引:2,自引:0,他引:2
T McLellan M A Pryor J P Kushner R L Eddy T B Shows 《Cytogenetics and cell genetics》1985,39(3):224-227
The assignment of the human gene for uroporphyrinogen decarboxylase (UROD) to chromosome 1 is confirmed and further localized to the pter----p21 region through the use of human-mouse somatic cell hybrids. Human and mouse UROD were separated by electrophoresis and identified with antibodies to the human enzyme after electrophoretic transfer to nitrocellulose membranes. 相似文献
404.
Acute altitude exposure and altered acid-base states. I. Effects on the exercise ventilation and blood lactate responses 总被引:1,自引:0,他引:1
T McLellan I Jacobs W Lewis 《European journal of applied physiology and occupational physiology》1988,57(4):435-444
This study examined the influence of acute altitude (AL) exposure alone or in combination with metabolic acid-base manipulations on the exercise ventilatory and blood lactate responses. Four subjects performed a 4 min, 30 W incremental test to exhaustion at ground level (GL) and a 4 min, 20 W incremental test during three acute exposures to a simulated altitude of 4200 m; (i) normal (NAL), (ii) following 0.2 g.kg-1 ingestion of sodium bicarbonate (BAL), and (iii) following 0.5 g.day-1 ingestion of acetazolamide for 2 days prior to exposure (AAL). VE.VO2-1 increased progressively throughout the incremental tests at AL and the minimum value was not related to a change in the blood lactate response. In contrast, the VE.VCO2-1 decreased initially to reach a minimum value at the same power output for each altitude trial and was related to a lactate threshold defined by a log-log transformation (r = 0.78). This transformation of the blood lactate data was not influenced by the altered acid-base states. The relative exercise intensity corresponding to both a delta lactate of 1 mM and an absolute lactate of 4 mM was significantly increased during the AAL (79.9 +/- 12.9 and 93.9 +/- 13.7% VO2max, respectively) compared with NAL (59.1 +/- 5.5 and 78.0 +/- 5.8% VO2max, respectively). These data suggest that strong relationships exist between the ventilatory and blood lactate response during AL exposure and altered acid-base states. Further, it is concluded that, unless the acid-base status is known, the use of an absolute or delta lactate value to compare submaximal exercise should be interpreted with caution. 相似文献
405.
Summary This study dealt with the ability of non-denaturing gel electrophoresis to separate iso-1-cytochromec with single amino acid replacements isolated from revertants of variouscyc1 nonsense mutants of the yeastSaccharomyces cerevisiae. A total of 28 different iso-1-cytochromesc with single amino acid substitutions of one of seven amino acids at six positions were examined on nondenaturing polyacrylamide gels at pH 4.8. Each of these iso-1-cytochromesc exhibited 1 of 16 distinct electrophoretic mobilities. We could distinguish the majority of iso-1-cytochromesc, even those having the same replacement at different sites and those having different replacements that resulted in the same net charge. These results provide confirmation of the importance of site-specific effects on the electrophoretic mobility, and presumably other properties, of proteins differing in sequence by as little as one amino acid. They demonstrate that nondenaturing electrophoresis is able to separate the majority of, but not all, proteins differing by single amino acids. 相似文献
406.
Fourteen myoglobins of known sequence were examined by isoelectric focusing with and without urea. The 14 sequences formed six distinct mobility classes on gels without urea and three classes on those with urea. For these proteins, isoelectric focusing provides no advantage over single, nonequilibrium, nondenaturing gels in the total number of distinguishable mobility classes. Only major charge differences, resulting from the changes in the total numbers of acidic and basic amino acids, can be detected on gels with urea, indicating that denaturation by urea alters proteins so that small differences in ionization are eliminated.We thank the Department of Biology, University of Utah, for financial support. 相似文献
407.
A simple model was developed to describe the transport of water vapour from subjects working in hot environments while wearing
chemical-protective clothing. The goal of the modelling was to obtain a better estimate of evaporative cooling of the subjects,
as it was hypothesised that calculations of evaporative heat loss based on changes in dressed weight over-estimate the actual
benefit experienced by the subjects. The model employed measured values of vapour pressure within the clothing ensemble to
estimate the skin vapour pressure. The resistance of the clothing ensemble to water vapour transport was calculated from measurements
of the physical properties of the materials in conjunction with estimates of the resistance of air layers between the clothing
layers. The model predicts mean evaporation rates from the skin that are approximately 60% of those calculated from measured
changes in dressed weight. Error analysis failed to account for the magnitude of this difference and possible explanations
for the difference are advanced. A brief examination of the effect of wicking suggests that some of the difference results
from a reduction of the resistance of the garment to water vapour due to wicking of liquid sweat through fabric layers.
Received: 4 June 1997 / Accepted: 21 October 1997 相似文献
408.
Human clinical and psychophysical observations suggest that the taste
system is able to compensate for losses in peripheral nerve input, since
patients do not commonly report decrements in whole mouth taste following
chorda tympani nerve damage or anesthesia. Indeed, neurophysiological data
from the rat nucleus of the solitary tract (NST) suggests that a release of
inhibition (disinhibition) may occur centrally following chorda tympani
nerve anesthesia. Our purpose was to study this possibility further. We
recorded from 59 multi- and single- unit taste-responsive sites in the rat
NST before, during and after recovery from chorda tympani nerve anesthesia.
During anesthesia, average anterior tongue responses were eliminated but no
compensatory increases in palatal or posterior tongue responses were
observed. However, six individual sites displayed increased taste
responsiveness during anesthesia. The average increase was 32.9%.
Therefore, disinhibition of taste responses was observed, but infrequently
and to a small degree in the NST At a subset of sites, chorda
tympani-mediated responses decreased while greater superficial
petrosal-mediated responses remained the same during anesthesia. Since this
effect was accompanied by a decrease in spontaneous activity, we propose
that taste compensation may result in part by a change in signal-to-noise
ratio at a subset of sites.
相似文献