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101.
Elizabeth B. Hirsch Brian R. Raux Jason W. Lancaster Rachael L. Mann Steven N. Leonard 《PloS one》2014,9(10)
Background
The use of tablet computers and other touch screen technology within the healthcare system has rapidly expanded. It has been reported that these devices can harbor pathogens in hospitals; however, much less is known about what pathogens they can harbor when used outside the hospital environment compared to hospital practice.Methods
Thirty iPads belonging to faculty with a variety of practice settings were sampled to determine the presence and quantity of clinically-relevant organisms. Flocked nylon swabs and neutralizer solution were used to sample the surface of each iPad. Samples were then plated on a variety of selective agars for presence and quantity of selected pathogens. In addition, faculty members were surveyed to classify the physical location of their practice settings and usage patterns. Continuous variables were compared via an unpaired Student''s t test with two-tailed distribution; categorical variables were compared with the Fisher''s exact test.Results
Of the iPads sampled, 16 belonged to faculty practicing within a hospital and 14 belonged to a faculty member practicing outside a hospital. More faculty within the hospital group used their iPads at their practice sites (78.6% vs. 31.3%; p = 0.014) and within patient care areas (71.4% vs. 18.8%; p = 0.009) than the non-hospital group. There were no differences in the presence, absence, or quantity of, any of the pathogens selectively isolated between groups. Problematic nosocomial pathogens such as methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and P. aeruginosa were isolated from both hospital and non-hospital faculty iPads.Conclusions
Gram positive and Gram negative organisms were recovered from the surfaces of iPads regardless of practice setting; these included problematic multidrug-resistant pathogens like MRSA, VRE, and Pseudomonas aeruginosa. Healthcare personnel in all settings should be aware of the potential for tablet computers to serve as a nidus for microorganism transmission. 相似文献102.
Trophy hunting is one of the most controversial issues in the field of biodiversity conservation. In particular, proponents and opponents debate fiercely over whether it poses a threat to hunted populations. Here, we show that trophy hunting constitutes a greater menace to threatened species than previously realized. Because humans value rarity, targeted species that are threatened are likely to be disproportionately hunted, thereby becoming even more vulnerable, which could eventually push them to extinction. With the ten felid species currently hunted for their trophies, we present evidence that (1) the number of killed individuals increases with time, in several cases exponentially, despite population declines, (2) the price of trophies is strongly dependent on species protection status, (3) changes of protection status coincide with counter-intuitive changes of hunting pressures: protection intensification with augmented hunting effort, and protection relaxation with lower effort. This suggests an over-exploitation of trophy-hunted felids and the necessity of a better quota system coupled with reconsidered protection methods. 相似文献
103.
104.
The herpes simplex virus 1 (HSV-1) U(L)21 gene encodes a 62-kDa tegument protein with homologs in the alpha-, beta-, and gammaherpesvirus subfamilies. In the present study, we characterized a novel U(L)21-null virus and its genetic repair to determine whether this protein plays a role in early stages of the HSV-1 replication cycle. Single-step growth analyses, protein synthesis time courses, and mRNA quantifications indicated that the absence of U(L)21 results in a delay early in the HSV-1 replication cycle. 相似文献
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106.
Sheri Zidenberg-Cherr Carl L. Keen Lucille S. Hurley 《Biological trace element research》1985,7(1):31-48
The influence of manganese deficiency on liver trace element concentration, MnSOD activity, and mitochondrial structure and function during postnatal development was determined in rats. In both normal and manganese-deficient animals, liver manganese concentration increased with time, but in deficient rats liver manganese was lower than in controls at all ages measured. At 9 mo of age, liver manganese concentration in the deficient rats was only 20% that of controls. The developmental pattern observed for MnSOD paralleled that of liver manganese concentration in normal and deficient rats; it was lower than in controls on days 20 and 60. However, at 9 mo of age, MnSOD levels were similar in the two groups. Although there were no differences at 9 mo of age in MnSOD activity between the groups, manganese-deficient rats showed mitochondrial abnormalities in liver. Despite mitochondrial abnormalities, however, oxygen uptake and P/O ratios were normal. We suggest that the mitochondrial damage apparent at 9 mo of age is, at least in part, the result of lower than normal MnSOD activity occurring earlier. The functional significance of the abnormalities remains to be established. 相似文献
107.
In situ immunoassays for gene translation products in phage plaques and bacterial colonies 总被引:1,自引:0,他引:1
A series of simple, in situ immunoassays have been developed which can be used in screening for translation products of genes cloned in vitro recombination experiments with either phage or plasmid vectors. Antigen-antibody complex formation occurring within a vector-phage plaque can be used to detect the production of a specific protein from an amplified gene. Immunoassays of colonies lysed in situ either by λ prophage induction or by biochemical means afford a much higher level of sensitivity than the plaque assay probably adequate to detect the production of a few molecules of protein per cell. 相似文献
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109.
Summary Isolates ofT. mentagrophytes andT. rubrum are encountered that cannot be distinguished from each other solely on the basis of morphological criteria.Since these two species fundamentally differ in the manner in which they attack hairin vitro, this property can be used as a diagnostic aid, when correlated with their morphologic characteristics as developed on a variety of media.
T. mentagrophytes radially penetrates hair segments immersed in water forming wedge-shaped perforations.T. rubrum does not perforate hair.The method of determining the ability or inability ofT. mentagrophytes orT. rubrum to perforate hair and the use of this test in identifying those species are described. 相似文献
110.