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131.
Ecosystems - A correction to this paper has been published: https://doi.org/10.1007/s10021-021-00614-y  相似文献   
132.
BackgroundSoil-transmitted helminths (STH) are common in low and middle income countries where there is lack of access to clean water and sanitation. Effective diagnosis and treatment are essential for the control of STH infections. However, among STH parasites, Strongyloides stercoralis is the most neglected species, both in diagnostics and control strategies. Diagnostic methods cover different approaches, each with different sensitivities and specificities, such as serology, molecular techniques and microscopy based techniques. Of the later, the Baermann technique is the most commonly used procedure. In the literature, several ways have been described to perform the Baermann method, which illustrates the overall lack of a ‘(gold) reference standard’ method for the diagnosis of S. stercoralis infection. In this study we have evaluated the performance of three Baermann techniques in order to improve the reference standard for the microscopic diagnosis of S. stercoralis infection thereby facilitating individual case detection, mapping of the disease and proper evaluation of treatment responses.Methods/Principal findingsA community based cross sectional study was conducted at Zenzelima, Bahir Dar Zuria Ethiopia. A total of 437 stool samples were collected and analyzed by the following procedures: conventional Baermann (CB), modified Baermann (MB), and modified Baermann with charcoal pre-incubation (MBCI). The diagnostic sensitivity and Negative Predictive Value (NPV) of each technique was calculated using the combination of all the three techniques as a composite reference standard. Our result indicated that larvae of S. stercoralis were detected in 151 (34.6%) stool samples. The prevalence of S. stercoralis infection based on the three diagnostic methods was 9.6%, 8.0%, and 31.3% by CB, MB, and MBCI respectively. The sensitivity and NPV for CB, MB, and MBCI were 26.7% and 70.8%, 22.1% and 69.6%, and 87.0% and 93.2%, respectively. The MBCI showed significant difference (P- value = <0.001) in the sensitivity and NPV values when compared with CB and MB values. The agreement between CB, MB, and MBCI with the composite reference standard was 31.8%, 26.7%, 89.6%, respectively.Conclusion/SignificanceOur results suggest the superior performance of MBCI. It is relatively easy to implement, simple to perform and comparatively cheaper. The CB is by far the commonly used method in routine diagnostic although this technique significantly underestimates the true burden of the disease and thereby contributing to the exclusion of S. stercoralis from the control strategies. Therefore, MBCI is recommended as a routine microscopy-based diagnostic test for S. stercoralis infection, particularly in settings where molecular procedures are not available.  相似文献   
133.
PurposePreload of antagonist muscles can be achieved by reciprocal actions (RAs) or by opposing muscle actions. However, evidence concerning neuromuscular and fatigue responses are scarce.ObjectiveTo compare the effects of different knee flexor (KF) preload methods on knee extension (KE) vastus medialis muscle fatigue, based on EMG-spectral index (FI), load range (LR), total work (TW), blood lactate (LAC) and biceps femoris co-activation (BFc) during resistance exercise.MethodsTwenty-four healthy men (23.5 ± 3.6 yrs) performed three antagonist pre-load isokinetic exercises (4 sets, 10 repetitions, 60° s?1, 1 min rest between sets): RA (KF contraction immediately followed by KE); Superset (SS; one KF set immediately followed by one KE set); Multiple Set (MS; four KF sets followed by four KE sets).ResultsTotal work was significantly greater in RA. There was no significant decrease in LR between sets in RA. The BFc did not differ between protocols (p = 0.063). However, RA presented greater biceps femoriscoactivation. The FI was greater during SS compared to RA and MS (p < 0.05). The SS had greater LAC when compared to MS and RA (p = 0.005 and p = 0.007, respectively).ConclusionIt is suggested that the RA protocol is more neuromuscular and metabolic efficient during the performance of knee extension resistance exercise.  相似文献   
134.
In the absence of redox-active transition metal ions, the removal of Tempol by Trolox occurs by a simple bimolecular reaction that, most probably, involves a hydrogen transfer from phenol to nitroxide. The specific rate constant of the process is small (0.1 M &#109 1 s &#109 1 ). Metals can catalyze the process, as evidenced by the decrease in rate observed in the presence of diethylenetriaminepentaacetic acid (DTPA). Furthermore, addition of Fe(II) (20 &#119 M ferrous sulfate and 40 &#119 M EDTA) produces a noticeable increase in the rate of Tempol consumption.  相似文献   
135.
Gay–Straight Alliances (GSAs) are student-led, school-based clubs that aim to provide a safe environment in the school context for lesbian, gay, bisexual, and transgender (LGBT) students, as well as their straight allies. The present study examines the potential for GSAs to support positive youth development and to reduce associations among LGBT-specific school victimization and negative young adult well-being. The sample includes 245 LGBT young adults, ages 21–25, who retrospectively reported on the presence of a GSA in their high school, their participation in their school's GSA, and their perceptions of whether or not their GSA was effective in improving school safety. Findings revealed that the presence of a GSA, participation in a GSA, and perceived GSA effectiveness in promoting school safety were differentially associated with young adult well-being and, in some cases, buffered the negative association between LGBT-specific school victimization and well-being. Implications for future research and schools are discussed.  相似文献   
136.
Abstract

Contribution to the Myxomycetes flora of Italy. — In this work 52 species, 20 of which new to Italy, are named. The specimens were collected in northern and central Italy.  相似文献   
137.
138.
Because of the high adaptive capacity of mosquitoes, studies that focus on transitional environments become very important, such as those in rural areas, which are considered as bridges between wild diseases and human populations of urban areas. In this study, a survey of the existing species of mosquitoes was performed in an Atlantic Forest area of the city of Santa Bárbara d'Oeste, São Paulo state, Brazil, using traps for immatures and analyzing the frequency and distribution of these insects over the sampling months. Five mosquito species were found: Aedes albopictus (the most frequent species), Aedes aegypti, Aedes fluviatilis, Culex quinquefasciatus, and Toxorhynchites theobaldi. The 4,524 eggs collected in ovitraps showed the presence of the tribe Aedini. Aedes aegypti and Ae. albopictus were identified after larval hatching in the laboratory, with different spatial distributions: the first of which coincides with the area of greatest diversity calculated using the Simpson index, while the second does not. The association of ecological analysis of spatial diversity with simple methods of data collection enables the identification of possible epidemiological risk situations and is a strategy that may be implemented to monitor ecological processes resulting from the interaction among different species of mosquitoes.  相似文献   
139.
BackgroundAn allogeneic hematopoietic cell transplantation (allo-HCT) patient presented with chronic pulmonary aspergillosis associated to pulmonary graft versus host disease (GVHD) and was treated for a long time with several antifungal agents that were administered as prophylaxis, combination therapies, and maintenance treatment. The patient suffered from a breakthrough invasive pulmonary aspergillosis due to Aspergillus fumigatus after long-term antifungal therapy.Material and methodsSeveral isolates were analyzed. First isolates were susceptible in vitro to all azole agents. However, after prolonged treatment with itraconazole and voriconazole a multiple azole resistant A. fumigatus isolate was cultured from bronchoalveolar lavage (BAL) when the patient was suffering from an invasive infection, and cavitary lesions were observed.ResultsAnalysis of the resistant mechanisms operating in the last strain led us to report the first isolation in Spain of an azole resistant A. fumigatus strain harboring the L98H mutation in combination with the tandem repeat (TR) alteration in CYP51A gene (TR-L98H). Long-term azole therapy may increase the risk of resistance selecting strains exhibiting reduced susceptibility to these compounds. However, since the isolates were genetically different the suggestion that could be made is that the resistance was not induced during the prolonged azole therapy but the patient might simply have acquired this resistant isolate from the environment, selected by the therapy.ConclusionsThese findings suggest that in all long-term treatments with antifungal agents, especially with azoles, repeated sampling and regular susceptibility testing of strains isolated is necessary as resistant isolates could be selected.  相似文献   
140.
Heteropteran legs are very diverse within and among taxa, and such variation is frequently correlated with life habits. Structural modifications are commonly present in the legs of the Pentatomoidea but are poorly studied. Using scanning electron microscopy, the tibia and pretarsal microstructure of 82 species of Pentatomidae (Heteroptera), three species of Scutelleridae, and ten species of Thyreocoridae were described, focusing on the pretarsal structure, the foretibial apparatus, and the foretibial comb. The Pentatomidae, the Scutelleridae, and the Thyreocoridae have uniform pretarsal structures. Variation can be found in the length of the parempodial setae and in the shape of the parempodial projections. The foretibial combs of the Pentatomidae, the Thyreocoridae, and the Scutelleridae are described for the first time, and we have demonstrated that there is low structural variation in the foretibial comb complex of the studied species. The setae organization and distribution on the foretibial apparatus is uniform in the families studied. However, the Asopinae (Pentatomidae) bear a foretibial apparatus that is uniquely organized. The taxonomic and phylogenetic relevance of the pretarsal traits, the foretibial apparatus, and the foretibial comb are discussed.  相似文献   
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