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11.
AB Johan Groeneveld 《BMC anesthesiology》2007,7(1):1-8
We have developed a two-step procedure for preparing the skin before peripheral venous catheter (PVC) insertions. This procedure involves two successive swabbings with wipes soaked in alcoholic antiseptic. We investigated whether this two-step procedure was as effective and safe as the standard four-step procedure – washing with detergent, rinsing, drying, applying antiseptic – by carrying out a multicentre randomised equivalence study comparing the frequency of precursor signs of infection at the site of insertion for the two skin preparation procedures. The study was carried out over an eight-month period, and 248 PVC insertion sites were evaluated. The two-step procedure was used for 130 subjects and the standard procedure for 118. Taking into account all the confounding factors predisposing patients to the complications studied, the characteristics of the two groups of patients were found to be similar, with no significant differences noted. The incidence of precursor signs of infection was 11 % 24 hours after PVC insertion (27/248), 25 % at 48 hours (50/203) and at 29 % at 72 hours (34/119). Eleven patients had complications necessitating the withdrawal of the PVC: sensitivity of the insertion site, with redness and/or slight swelling and/or a palpable venous cord. No major complications were observed in this study. The frequency of local complications associated with PVCs reported in this study, whether simple or severe, was not affected by the skin preparation procedure used for PVC insertion (two-step or four-step procedure). 相似文献
12.
Global conservation priorities for marine turtles 总被引:2,自引:0,他引:2
Wallace BP DiMatteo AD Bolten AB Chaloupka MY Hutchinson BJ Abreu-Grobois FA Mortimer JA Seminoff JA Amorocho D Bjorndal KA Bourjea J Bowen BW Briseño Dueñas R Casale P Choudhury BC Costa A Dutton PH Fallabrino A Finkbeiner EM Girard A Girondot M Hamann M Hurley BJ López-Mendilaharsu M Marcovaldi MA Musick JA Nel R Pilcher NJ Troëng S Witherington B Mast RB 《PloS one》2011,6(9):e24510
Where conservation resources are limited and conservation targets are diverse, robust yet flexible priority-setting frameworks are vital. Priority-setting is especially important for geographically widespread species with distinct populations subject to multiple threats that operate on different spatial and temporal scales. Marine turtles are widely distributed and exhibit intra-specific variations in population sizes and trends, as well as reproduction and morphology. However, current global extinction risk assessment frameworks do not assess conservation status of spatially and biologically distinct marine turtle Regional Management Units (RMUs), and thus do not capture variations in population trends, impacts of threats, or necessary conservation actions across individual populations. To address this issue, we developed a new assessment framework that allowed us to evaluate, compare and organize marine turtle RMUs according to status and threats criteria. Because conservation priorities can vary widely (i.e. from avoiding imminent extinction to maintaining long-term monitoring efforts) we developed a “conservation priorities portfolio” system using categories of paired risk and threats scores for all RMUs (n = 58). We performed these assessments and rankings globally, by species, by ocean basin, and by recognized geopolitical bodies to identify patterns in risk, threats, and data gaps at different scales. This process resulted in characterization of risk and threats to all marine turtle RMUs, including identification of the world''s 11 most endangered marine turtle RMUs based on highest risk and threats scores. This system also highlighted important gaps in available information that is crucial for accurate conservation assessments. Overall, this priority-setting framework can provide guidance for research and conservation priorities at multiple relevant scales, and should serve as a model for conservation status assessments and priority-setting for widespread, long-lived taxa. 相似文献
13.
AB Chang NC Cox J Purcell JM Marchant PJ Lewindon GJ Cleghorn LC Ee GD Withers MK Patrick J Faoagali 《Respiratory research》2005,6(1):1-5
Background and methods
Human metapneumovirus (hMPV) is a recently discovered respiratory virus associated with bronchiolitis, pneumonia, croup and exacerbations of asthma. Since respiratory viruses are frequently detected in patients with acute exacerbations of COPD (AE-COPD) it was our aim to investigate the frequency of hMPV detection in a prospective cohort of hospitalized patients with AE-COPD compared to patients with stable COPD and to smokers without by means of quantitative real-time RT-PCR.Results
We analysed nasal lavage and induced sputum of 130 patients with AE-COPD, 65 patients with stable COPD and 34 smokers without COPD. HMPV was detected in 3/130 (2.3%) AE-COPD patients with a mean of 6.5 × 105 viral copies/ml in nasal lavage and 1.88 × 105 viral copies/ml in induced sputum. It was not found in patients with stable COPD or smokers without COPD.Conclusion
HMPV is only found in a very small number of patients with AE-COPD. However it should be considered as a further possible viral trigger of AE-COPD because asymptomatic carriage is unlikely. 相似文献14.
Background
Burkholderia pseudomallei is a saprophyte in tropical environments and an opportunistic human pathogen. This versatility requires a sensing mechanism that allows the bacterium to respond rapidly to altered environmental conditions. We characterized a two-component signal transduction locus from B. pseudomallei 204, mrgR and mrgS, encoding products with extensive homology with response regulators and histidine protein kinases of Escherichia coli, Bordetella pertussis, and Vibrio cholerae. 相似文献15.
Summary There are several sources of potential error in calculating the concentration or energy value of floral nectar. Errors resulting from confusing data become substantial with increasing concentration. The different methods of expressing sugar concentration are here clarified, and the correct methods of converting from one to the other are provided. Refractometers in use in field studies usually read on a weight per total weight basis; this is recommended as the mode of statement. The perils of oversimplifying conversions from this mode, as is often done, are pointed out. 相似文献
16.
Rodrigues AL Göcke Y Bolten C Brock NL Dickschat JS Wittmann C 《Biotechnology letters》2012,34(4):717-720
Violacein and deoxyviolacein display a broad range of interesting biological properties but their production is rarely distinguished
due to the lack of suitable analytical methods. An HPLC method has been developed for the separation and quantification of
violacein and deoxyviolacein and can determine the content of both molecules in microbial cultures. A comparison of different
production microorganisms, including recombinant Escherichia coli and the natural producer Janthinobacterium lividum, revealed that the formation of violacein and deoxyviolacein is strain-specific but showed significant variation during growth
although the ratio between the two compounds remained constant. 相似文献
17.
KA Havens JM Guseman SS Jang E Pierre-Jerome N Bolten E Klavins JL Nemhauser 《Plant physiology》2012,160(1):135-142
Explaining how the small molecule auxin triggers diverse yet specific responses is a long-standing challenge in plant biology. An essential step in auxin response is the degradation of Auxin/Indole-3-Acetic Acid (Aux/IAA, referred to hereafter as IAA) repressor proteins through interaction with auxin receptors. To systematically characterize diversity in degradation behaviors among IAA|receptor pairs, we engineered auxin-induced degradation of plant IAA proteins in yeast (Saccharomyces cerevisiae). We found that IAA degradation dynamics vary widely, depending on which receptor is present, and are not encoded solely by the degron-containing domain II. To facilitate this and future studies, we identified a mathematical model able to quantitatively describe IAA degradation behavior in a single parameter. Together, our results demonstrate the remarkable tunability conferred by specific configurations of the auxin response pathway. 相似文献
18.
19.
Gomes CM Donadio MV Anselmo-Franci J Franci CR Lucion AB Sanvitto GL 《Life sciences》2006,78(25):2867-2871
Neonatal handling affects the hypothalamus-pituitary-gonadal axis in female rats. Indeed, postnatal handling induces anovulatory estrous cycles and decreases sexual receptiveness. On the other hand, Angiotensin II (Ang II) infused into the medial amygdala (MeA) reduces sexual behavior in male and female rats. Considering this, and that gonadal steroid secretion after copulatory behavior is important for reproductive success, the purpose of the present study was to investigate whether the reduction in sexual receptiveness in neonatally handled female rats is mediated by changes in Ang II receptor density in MeA. Moreover, gonadal steroid secretion after sexual behavior was analyzed. Two groups of female Wistar rats were studied: nonhandled (pups were left undisturbed) and handled (pups were handled for 1 min once a day during the first 10 days of life). Once they were 80-85 days old in the evening of the proestrus day, sexual receptiveness was recorded and after that the animals were killed by decapitation. Trunk blood samples were collected, and plasma estradiol and progesterone were measured by radioimmunoassay. The brains were removed for Ang II receptor autoradiography in MeA. The decreased lordosis quotient in the neonatally handled group was confirmed in the present study. Neonatal handling also reduced the progesterone concentration in the plasma, but did not change the estradiol and the density of Ang II receptors in MeA. The reduced progesterone could be due to the decreased lordosis frequency of handled females. However, this decreased sexual receptiveness is not mediated by changes in Ang II receptors in MeA. 相似文献
20.
The genes sup-7 X and sup-5 III of C. elegans suppress amber nonsense mutations via altered transfer RNA 总被引:25,自引:0,他引:25
The sup-5 III and sup-7 X suppressors in C. elegans have previously been shown to have many genetic properties in common with tRNA nonsense suppressors of microorganisms. We report here the results of two lines of investigation into the molecular basis of these suppressors. In one, which sought to determine the nature of suppressible alleles, we demonstrate through DNA sequencing studies that a suppressible allele, unc-54(e 1300) I, of the myosin heavy chain gene contains a C leads to T substitution, which changes a glutamine codon to amber terminator at residue 1903. In the other approach, which sought to define the nature of the suppressing activity, we show through in vitro translation studies that tRNA fractions from the suppressor strains, but not wild-type, promote the specific readthrough of amber terminators of three different messenger RNAs. We conclude that sup-5 and sup-7 result in readthrough of amber terminators in vivo through an altered tRNA. 相似文献