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81.
Background
A vast number of biomechanical studies have employed inverse dynamics methods to calculate inter-segmental moments during movement. Although all inverse dynamics methods are rooted in classical mechanics and thus theoretically the same, there exist a number of distinct computational methods. Recent research has demonstrated a key influence of the dynamics computation of the inverse dynamics method on the calculated moments, despite the theoretical equivalence of the methods. The purpose of this study was therefore to explore the influence of the choice of inverse dynamics on the calculation of inter-segmental moments. 相似文献82.
Background
Ensemble attribute profile clustering is a novel, text-based strategy for analyzing a user-defined list of genes and/or proteins. The strategy exploits annotation data present in gene-centered corpora and utilizes ideas from statistical information retrieval to discover and characterize properties shared by subsets of the list. The practical utility of this method is demonstrated by employing it in a retrospective study of two non-overlapping sets of genes defined by a published investigation as markers for normal human breast luminal epithelial cells and myoepithelial cells. 相似文献83.
84.
Sandrine MJ. Camus Céline Rochais Catherine Blois-Heulin Qin Li Martine Hausberger Erwan Bezard 《PloS one》2013,8(7)
Background
Adverse early-life experience might lead to the expression of abnormal behaviours in animals and the predisposition to psychiatric disorder (e.g. major depressive disorder) in Humans. Common breeding processes employ weaning and housing conditions different from what happens in the wild.Methods
The present study, therefore, investigated whether birth origin impacts the possible existence of spontaneous atypical/abnormal behaviours displayed by 40 captive-born and 40 wild-born socially-housed cynomolgus macaques in farming conditions using an unbiased ethological scan-sampling analysis followed by multifactorial correspondence and hierarchical clustering analyses.Results
We identified 10 distinct profiles (groups A to J) that significantly differed on several behaviours, body postures, body orientations, distances between individuals and locations in the cage. Data suggest that 4 captive-born and 1 wild-born animals (groups G and J) present depressive-like symptoms, unnatural early life events thereby increasing the risk of developing pathological symptoms. General differences were also highlighted between the captive- and wild-born populations, implying the expression of differential coping mechanisms in response to the same captive environment.Conclusions
Birth origin thus impacts the development of atypical ethologically-defined behavioural profiles, reminiscent of certain depressive-like symptoms. The use of unbiased behavioural observations might allow the identification of animal models of human mental/behavioural disorders and their most appropriate control groups. 相似文献85.
86.
ABSTRACT: BACKGROUND: Traditional medicine (TM) occupies a special place in the management of diseases in Uganda. Not with standing the many people relying on TM, indigenous knowledge (IK) related to TM is getting steadily eroded. To slow down this loss it is necessary to document and conserve as much of the knowledge as possible. This study was conducted to document the IK relevant to traditional medicine in the districts of Mukono, Nakapiripirit, Kanungu and Pallisa, in Uganda. METHODS: An ethnobotanical survey was conducted between October 2008 and February 2009 using techniques of key informant interviews and household interviews. RESULTS: The common diseases and conditions in the four districts include malaria, cough, headache, diarrhea, abdominal pain, flu, backache and eye diseases. Respondents stated that when they fall sick they self medicate using plant medicines or consult western-trained medicine practitioners. Self medication using herbal medicines was reported mostly by respondents of Nakapiripirit and Mukono. Respondents have knowledge to treat 78 ailments using herbal medicines. 44 species, mentioned by three or more respondents have been prioritized. The most frequently used part in herbal medicines is the leaf, followed by the stem and root. People sometime use animal parts, soil, salt and water from a grass roof, in traditional medicines. Herbal medicines are stored for short periods of time in bottles. The knowledge to treat ailments is acquired from parents and grandparents. Respondents' age and tribe appears to have a significant influence on knowledge of herbal medicine, while gender does not. CONCLUSION: This survey has indicated that IK associated with TM stills exists and that TM is still important in Uganda because many people use it as a first line of health care when they fall sick. Age and tribe influence the level of IK associated with herbal medicine, but gender does not. 相似文献
87.
Kristof Theys Koen Deforche Jurgen Vercauteren Pieter Libin David AMC van de Vijver Jan Albert Birgitta ?sj? Claudia Balotta Marie Bruckova Ricardo J Camacho Bonaventura Clotet Suzie Coughlan Zehava Grossman Osamah Hamouda Andrzei Horban Klaus Korn Leondios G Kostrikis Claudia Kücherer Claus Nielsen Dimitrios Paraskevis Mario Poljak Elisabeth Puchhammer-Stockl Chiara Riva Lidia Ruiz Kirsi Liitsola Jean-Claude Schmit Rob Schuurman Anders S?nnerborg Danica Stanekova Maja Stanojevic Daniel Struck Kristel Van Laethem Annemarie MJ Wensing Charles AB Boucher Anne-Mieke Vandamme 《Retrovirology》2012,9(1):1-13
Background
Bone marrow stromal cell antigen 2 (BST-2) is a cellular factor that restricts the egress of viruses such as human immunodeficiency virus (HIV-1) from the surface of infected cells, preventing infection of new cells. BST-2 is variably expressed in most cell types, and its expression is enhanced by cytokines such as type I interferon alpha (IFN-??). In this present study, we used the beta-retrovirus, mouse mammary tumor virus (MMTV) as a model to examine the role of mouse BST-2 in host infection in vivo.Results
By using RNA interference, we show that loss of BST-2 enhances MMTV replication in cultured mammary tumor cells and in vivo. In cultured cells, BST-2 inhibits virus accumulation in the culture medium, and co-localizes at the cell surface with virus structural proteins. Furthermore, both scanning electron micrograph (SEM) and transmission electron micrograph (TEM) show that MMTV accumulates on the surface of IFN??-stimulated cells.Conclusions
Our data provide evidence that BST-2 restricts MMTV release from naturally infected cells and that BST-2 is an antiviral factor in vivo. 相似文献88.
89.
A Desktop Apparatus for Studying Interactions Between Microorganisms and Small-Scale Fluid Motion 总被引:1,自引:0,他引:1
Low levels of kinetic energy dissipation were successfully generated in a reactor using two submersible speakers. A software
programme controlled the amplitude and frequency of the signal fed to each speaker and achieved good repeatability of flow
conditions. The flow reactor had a near isotropic flow regime with a low mean flow, values were calculated from particle image
velocimetry measurements. The flow characteristics compared well with grid turbulence reactors, though as no moving parts
are present in this reactor design the strain rates were lower compared to oscillating grid set-ups. The low range of Reynolds
numbers based on Taylor microscales (Reλ~0.5–5.9) covered both turbulent and non-turbulent flow regimes. The small-scale fluid motion produced over the entire volume
of this reactor makes it suitable for experiments examining the physiological responses of fluid motion on microorganisms. 相似文献
90.
Tracey E Toms Vasileios F Panoulas Karen MJ Douglas Helen R Griffiths George D Kitas 《Arthritis research & therapy》2008,10(6):1-8
Lupus nephritis is a major contributor to morbidity and mortality in systemic lupus erythematosus, but little is known about the pathogenic processes that underlie the progressive decay in renal function. A common finding in lupus nephritis is thickening of glomerular basement membranes associated with immune complex deposition. It has been speculated that alterations in the synthesis or degradation of membrane components might contribute to such changes, and thereby to initiation and progression of nephritis through facilitation of immune complex deposition. Matrix metalloproteinases (MMPs) are enzymes that are intimately involved in the turnover of major glomerular basement membrane constituents, including collagen IV and laminins. Alterations in the expression and activity of MMPs have been described in a number of renal diseases, suggesting their relevance to the pathogenesis of various glomerulopathies. The same is true for their natural inhibitors, the tissue inhibitor of metalloproteinase family. Recent data from our group have identified an increase in proteolytic activity within the glomerulus coinciding with the development of proteinuria in the mouse model of systemic lupus erythematosus. (NXB × NZW)F1 Here we review current understanding of MMP/tissue inhibitor of metalloproteinase function within the kidney, and discuss their possible involvement in the development and progression of lupus nephritis. 相似文献