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1.
Human gut microbiome is a diversified, resilient, immuno-stabilized, metabolically active and physiologically essential component of the human body. Scientific explorations have been made to seek in-depth information about human gut microbiome establishment, microbiome functioning, microbiome succession, factors influencing microbial community dynamics and the role of gut microbiome in health and diseases. Extensive investigations have proposed the microbiome therapeutics as a futuristic medicine for various physiological and metabolic disorders. A comprehensive outlook of microbial colonization, host–microbe interactions, microbial adaptation, commensal selection and immuno-survivability is still required to catalogue the essential genetic and physiological features for the commensal engagement. Evolution of a structured human gut microbiome relies on the microbial flexibility towards genetic, immunological and physiological adaptation in the human gut. Key features for commensalism could be utilized in developing tailor-made microbiome-based therapy to overcome various physiological and metabolic disorders. This review describes the key genetics and physiological traits required for host–microbe interaction and successful commensalism to institute a human gut microbiome. 相似文献
2.
Objectives: The purpose of this study was to analyze a comprehensive nationally representative data set to determine the effect of economic and non economic determinants on the decision to seek care and the decision to select a specific number of dental visits. Design: The conduct of this study involved the examination and analyses of secondary data available from the National Health Interview Survey. A two-pan choice logistic regression model was utilized to first describe the decision to seek care and second to describe factors associated with the decision to select a specific number of dental visits as a function of income, education, family size, age, marital status, presence of teeth, employment status, health status, gender, race, insurance status, and reason for dental visit. Subjects: Data analysis focused on 5.327 non-institutional older adults between the ages of 55 and 75 who were not eligible for Medicaid. Results: Results provide supporting evidence that income, presence of dental insurance, presence of teeth, gender, family size, education race and age are associated with the decision to seek dental care and that income, presence of dental insurance, gender, family size, education, and race are associated with the number of dental visits among users even when the effects of other variables are controlled for. Discussion : Analyses suggest that employment may have a surprisingly limited effect on dental utilisation and that among explanatory variables there are differences in significance and magnitude between the decision to seek care and the decision to select a specific number of dental visits. In addition, in contrast with some prior studies, health status does not appear to be associated with the decision to seek care or associated with the number of dental visits among respondents. 相似文献
3.
Stacy K. Li Donald H. Owings 《Ethology : formerly Zeitschrift fur Tierpsychologie》1978,46(4):359-371
The purpose of this study was to seek evidence for the influence of sexual selection on both male and female three-spined sticklebacks, a species in which the ♂ alone has parental responsibilities. We studied the intrasexual relationships of ♂♂ and ♀♀ prior to courtship, and the intrasexual and intersexual relationships of both sexes during courtship. Results demonstrated that both ♂♂ and ♀♀ compete intrasexually, and suggested that both sexes are discriminative in mate selection. These results are compatible with Trivers' (1972) model of the role of parental investment in sexual selection. 相似文献
4.
The accelerated development process for annual vaccines such as seasonal influenza presents unique challenges for the evaluation of vaccine stability. Real-time real-condition studies provide limited information at the time of registration, while regulators seek evidence that the current vaccine will perform satisfactorily in the field. Participants in the IABS Workshop on Stability Evaluation of Vaccines, a Life Cycle Approach, were offered a case study from the development of the 2007 influenza vaccine. The case study was introduced with preliminary data from the long-term study, as well as results from the completed year long study. The manufacturer also offered a proposed protocol for stability evaluation of vaccines developed in subsequent seasons. Participants were asked to answer a series of questions posed by the regulator, and critique the proposed stability protocol according to the principles described during the workshop. 相似文献
5.
Talent transfer initiatives seek to transfer talented, mature individuals from one sport to another. Unfortunately talent transfer initiatives seem to lack an evidence-based direction and a rigorous exploration of the mechanisms underpinning the approach. The purpose of this exploratory study was to identify the factors which successfully transferring athletes cite as facilitative of talent transfer. In contrast to the anthropometric and performance variables that underpin current talent transfer initiatives, participants identified a range of psycho-behavioral and environmental factors as key to successful transfer. We argue that further research into the mechanisms of talent transfer is needed in order to provide a strong evidence base for the methodologies employed in these initiatives. 相似文献
6.
缅甸琥珀生物群产自距今约98.8Ma的白垩纪中期,该生物群是世界上物种多样性很高的琥珀生物群之一,为了解白垩纪中期生物多样性和古生态提供了重要窗口。文中以近年来缅甸琥珀地层学、琥珀生物学研究为依据,总结缅甸琥珀形成环境,并对缅甸琥珀揭示的昆虫与植物的协同演化、昆虫的捕食、社会性证据、寄生、求偶和结构色等方面的研究结果进行总结,以期较全面地综述缅甸琥珀的古环境和昆虫行为生态学特征。 相似文献
7.
Carolina Eliscovich Adina R. Buxbaum Zachary B. Katz Robert H. Singer 《The Journal of biological chemistry》2013,288(28):20361-20368
Cells have evolved to regulate the asymmetric distribution of specific mRNA targets to institute spatial and temporal control over gene expression. Over the last few decades, evidence has mounted as to the importance of localization elements in the mRNA sequence and their respective RNA-binding proteins. Live imaging methodologies have shown mechanistic details of this phenomenon. In this minireview, we focus on the advanced biochemical and cell imaging techniques used to tweeze out the finer aspects of mechanisms of mRNA movement. 相似文献
8.
Entropy-enthalpy (SH) compensation occurs when a small change in DeltaG is caused by large, and nearly compensatory, changes in DeltaH and DeltaS. It is considered a ubiquitous property of reactions in water. Because water is intimately involved in protein stability, SH compensation among protein variants, if it exists, could lead to important knowledge about protein-water interactions. In light of recent theoretical work on SH compensation, we gathered thermodynamic data for >200 protein variants to seek evidence for the simplest quantitative model of SH compensation (i.e., The van't Hoff denaturation enthalpy divided by the van't Hoff denaturation entropy is a constant). We conclude that either the data are insufficient to support the idea that quantitative SH compensation is a general feature of variant proteins or that such compensation does not exist. This study reinforces the idea that DeltaH-versus-DeltaS plots should not be used to provide evidence for SH compensation. 相似文献
9.
Adoption behaviour by gulls: a new hypothesis 总被引:1,自引:0,他引:1
PERCY N. HÉBERT 《Ibis》1988,130(2):216-220
It appears that chicks are selected to run away and seek adoption in a foster-family when the level of investment they receive falls below a certain threshold. Predictions based on this hypothesis are in agreement with the available evidence in the literature. 相似文献
10.
Prockop DJ 《The Journal of cell biology》2003,160(6):807-809
In this issue, De Bari et al. (2003) present elegant data to counter the recent claims that adult stem cells have a limited plasticity. Further, they provide evidence that adult stem cells can seek out damaged tissues and repair them. 相似文献
11.
Pagel M 《Briefings in bioinformatics》2000,1(2):117-130
Phylogenies of organisms are essential to investigating a range of evolutionary questions of interest to researchers in the field of bioinformatics. Phylogenies not only help to define how to study many evolutionary questions, they must also be taken into account when conducting statistical analyses. Here it is shown how phylogenies can be used to investigate variability along the sites of a gene, reconstruct ancestral states of ancient genes and proteins, identify and characterise events of parallel and convergent evolution, find events of gene duplication, analyse predictions from molecular clocks, seek evidence for correlated changes among different parts of the same gene or genome, and test theories of molecular evolution. A table of statistical and phylogenetic methods is presented. 相似文献
12.
Migraine can be a disabling condition for the sufferer. For the small number of patients for whom home therapy fails and who seek treatment in an emergency department, several therapeutic options are available. I review the evidence regarding the effectiveness and safety of the following therapies: the phenothiazines, lignocaine (lidocaine), ketorolac, the ergot alkaloids, metoclopramide hydrochloride, the "triptans," haloperidol, pethidine (meperidine hydrochloride), and magnesium sulfate. Based on available evidence, the most effective agents seem to be prochlorperazine, chlorpromazine and sumatriptan, each of which has achieved greater than 70% efficacy in several studies. 相似文献
13.
Despite the growing popularity of supertree construction for combining phylogenetic information to produce more inclusive phylogenies, large-scale performance testing of this method has not been done. Through simulation, we tested the accuracy of the most widely used supertree method, matrix representation with parsimony analysis (MRP), with respect to a (maximum parsimony) total evidence solution and a known model tree. When source trees overlap completely, MRP provided a reasonable approximation of the total evidence tree; agreement was usually > 85%. Performance improved slightly when using smaller, more numerous, or more congruent source trees, and especially when elements were weighted in proportion to the bootstrap frequencies of the nodes they represented on each source tree ("weighted MRP"). Although total evidence always estimated the model tree slightly better than nonweighted MRP methods, weighted MRP in turn usually out-performed total evidence slightly. When source studies were even moderately nonoverlapping (i.e., sharing only three-quarters of the taxa), the high proportion of missing data caused a loss in resolution that severely degraded the performance for all methods, including total evidence. In such cases, even combining more trees, which had positive effects elsewhere, did not improve accuracy. Instead, "seeding" the supertree or total evidence analyses with a single largely complete study improved performance substantially. This finding could be an important strategy for any studies that seek to combine phylogenetic information. Overall, our results suggest that MRP supertree construction provides a reasonable approximation of a total evidence solution and that weighted MRP should be used whenever possible. 相似文献
14.
Barney A Martelli S Serrurier A Steele J 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2012,367(1585):88-102
Scientists seek to use fossil and archaeological evidence to constrain models of the coevolution of human language and tool use. We focus on Neanderthals, for whom indirect evidence from tool use and ancient DNA appears consistent with an adaptation to complex vocal-auditory communication. We summarize existing arguments that the articulatory apparatus for speech had not yet come under intense positive selection pressure in Neanderthals, and we outline some recent evidence and analyses that challenge such arguments. We then provide new anatomical results from our own attempt to reconstruct vocal tract (VT) morphology in Neanderthals, and document our simulations of the acoustic and articulatory potential of this reconstructed Neanderthal VT. Our purpose in this paper is not to polarize debate about whether or not Neanderthals were human-like in all relevant respects, but to contribute to the development of methods that can be used to make further incremental advances in our understanding of the evolution of speech based on fossil and archaeological evidence. 相似文献
15.
Lipid droplets as ubiquitous fat storage organelles in <Emphasis Type="Italic">C. elegans</Emphasis>
Background
Lipid droplets are a class of eukaryotic cell organelles for storage of neutral fat such as triacylglycerol (TAG) and cholesterol ester (CE). We and others have recently reported that lysosome-related organelles (LROs) are not fat storage structures in the nematode C. elegans. We also reported the formation of enlarged lipid droplets in a class of peroxisomal fatty acid β-oxidation mutants. In the present study, we seek to provide further evidence on the organelle nature and biophysical properties of fat storage structures in wild-type and mutant C. elegans. 相似文献16.
Parasite infection rather than tactile stimulation is the proximate cause of cleaning behaviour in reef fish. 总被引:5,自引:0,他引:5
A S Grutter 《Proceedings. Biological sciences / The Royal Society》2001,268(1474):1361-1365
Cleaning behaviour is a popular example of non-kin cooperation. However, quantitative support for this is generally sparse and the alternative, that cleaners are parasitic, has also been proposed. Although the behaviour involves some of the most complex and highly developed interspecific communication signals known, the proximate causal factors for why clients seek cleaners are controversial. However, this information is essential to understanding the evolution of cleaning. I tested whether clients seek cleaners in response to parasite infection or whether clients seek cleaners for tactile stimulation regardless of parasite load. Parasite loads on client fish were manipulated and clients exposed to cleaner fish and control fish behind glass. I found that parasitized client fish spent more time than unparasitized fish next to a cleaner fish. In addition, parasitized clients spent more time next to cleaners than next to control fish, whereas unparasitized fish were not attracted to cleaners. This study shows, I believe for the first time, which is somewhat surprising, that parasite infection alone causes clients to seek cleaning by cleaners and provides insight into how this behaviour evolved. 相似文献
17.
Captive Callitrichids frequently suffer a fatal wasting disease, wasting marmoset syndrome (WMS), of unexplained cause. This paper describes studies on the erythrocytes from animals in a breeding colony of tamarins (Saguinus labiatus), in which deaths from anaemia and wasting were occurring, to seek evidence for biochemical changes which could lead to oxidative damage and premature cell lysis. In only one animal of 33 studied did the red blood cell lipids show an increased susceptibility to oxidative damage. This animal, with some degree of certainty, could be diagnosed as having WMS. It was concluded that evidence for a primary deficiency of antioxidants as a cause of unexplained deaths, or WMS, in the colony could not at present be substantiated. 相似文献
18.
《应用发育科学》2013,17(2):128-135
Twenty-seven experienced interviewers attended a 10-day training institute designed to provide knowledge and skills for improving investigative interviews with young children. Participants completed pre- and posttraining surveys assessing their knowledge of the scientific evidence regarding memory, suggestibility, and other aspects of children's ability to provide accurate accounts of events during interviews. They also conducted pre- and posttraining interviews with preschool children about 2 previously experienced events. Participants' knowledge about children's abilities and the scientific basis of various interviewing protocols increased significantly after the training. However, training did not have a significant impact on interviewers' questioning styles or the amount of accurate information elicited from the children. Results indicate that successfully translating knowledge into practice requires multiple opportunities for skill practice and feedback. 相似文献
19.
Preclinical researchers confront two overarching agendas related to drug development: selecting interventions amid a vast field of candidates, and producing rigorous evidence of clinical promise for a small number of interventions. We suggest that each challenge is best met by two different, complementary modes of investigation. In the first (exploratory investigation), researchers should aim at generating robust pathophysiological theories of disease. In the second (confirmatory investigation), researchers should aim at demonstrating strong and reproducible treatment effects in relevant animal models. Each mode entails different study designs, confronts different validity threats, and supports different kinds of inferences. Research policies should seek to disentangle the two modes and leverage their complementarity. In particular, policies should discourage the common use of exploratory studies to support confirmatory inferences, promote a greater volume of confirmatory investigation, and customize design and reporting guidelines for each mode. 相似文献
20.
Rindy C. Anderson Casey A. Klofstad 《Ethology : formerly Zeitschrift fur Tierpsychologie》2012,118(9):841-849
A growing body of evidence shows that human mating preferences, like those of other animal species, can vary geographically. For example, women living in areas with a high cost of living have been shown to seek potential mates that can provide resources (e.g., large salaries). In this study, we present data from a large (N = 2944) nationally representative (United States) sample of Internet dating profiles. The profiles allowed daters’ to report their own income and the minimum income they desired in a dating partner, and we analyzed these data at the level of zip code. Our analysis shows that women engage in more resource seeking than men. We also find a positive relationship between cost of living in the dater's zip code and resource seeking among both men and women. Importantly, however, this relationship disappears if one's own income is accounted for in the analysis; that is, individuals of both sexes seek mates with an income similar to their own, regardless of local resource pressures. Our data highlight the importance of considering individual characteristics when measuring the effects of environmental factors on behavior. 相似文献