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1.
We describe an RsaI polymorphism in the transcribed region (exon 5) of the neurofibromatosis type 1 (NF1)-gene 相似文献
2.
The pike, Esox lucius Linnaeus, is a predatory fish that supports important fisheries and could substantially impact prey populations around the
temperate northern hemisphere. Consumption of prey by pike is most readily estimated using the energy budget to calculate
food intake indirectly using estimates of growth rate and metabolism. Resting metabolic rate, R
s, is a particularly important component of such calculations. Here, the available estimates of R
s are reviewed and compared. Scaling coefficients for variation with body mass are consistent between the two studies in which
they have been derived (0.81, 0.82). However, the effect of temperature on R
s markedly varies among studies (Q
10 from 1.73 to 4.80). There is substantial variation in R
s (twofold to fourfold) among studies when temperature and fish size are accounted for. This variation is shown to have a large
effect on energy budget calculations of energy intake and to be sufficient to account for imbalances in published budgets.
These effects depend on age of pike and season; in one energy budget model, a 50% reduction in R
s resulted in decrease of 19–42% in estimated energy intake of pike. Potential causes of among-study variation in R
s are discussed and it is recommended that standard techniques by applied in the future to differentiate between genuine biological
variation among populations and experimental factors.
Guest editors: J. M. Farrell, C. Skov, M. Mingelbier, T. Margenau & J. E. Cooper
International Pike Symposium: Merging Knowledge of Ecology, Biology, and Management for a Circumpolar Species 相似文献
3.
Benjamin Gilles Frank Kolo Christophe Nadia Magnenat-Thalmann Christoph D. Becker Sylvain R. Duc Jacques Menetrey Pierre Hoffmeyer 《Journal of biomechanics》2009,42(9):1201-1205
To better understand movement limitations and, to some extent, the pathogenesis of osteoarthritis, it is important to quantitatively measure femoroacetabular translations to assess if any joint subluxation occurs. In this paper, we aim at measuring hip joint displacements from magnetic resonance images (MRI) based on a surface registration technique. Because this measurement is related to the location of the hip joint center (HJC), we investigate and compare different HJC estimation approaches based on patient-specific 3D bone models. We estimate the HJC based on a simulated circumduction while minimizing inter-articular distance changes. Measurements of femoroacetabular translations during low amplitude abductions ( samples) and extreme flexions ( samples) in female professional dancers, which is a population potentially exposed to femoroactebaluar impingements, do not show any significant subluxation. 相似文献
4.
5.
Piekorz RP Hoffmeyer A Duntsch CD McKay C Nakajima H Sexl V Snyder L Rehg J Ihle JN 《The EMBO journal》2002,21(4):653-664
TACC3 is a centrosomal/mitotic spindle-associated protein that is highly expressed in a cell cycle-dependent manner in hematopoietic lineage cells. During embryonic development, TACC3 is expressed in a variety of tissues in addition to the hematopoietic lineages. TACC3 deficiency causes an embryonic lethality at mid- to late gestation involving several lineages of cells. Hematopoietic stem cells, while capable of terminal differentiation, are unable to be expanded in vitro or in vivo in reconstitution approaches. Although gross alterations in centrosome numbers and chromosomal segregation are not observed, TACC3 deficiency is associated with a high rate of apoptosis and expression of the p53 target gene, p21(Waf1/Cip1). Hematopoietic stem cell functions, as well as deficiencies in other cell lineages, can be rescued by combining the TACC3 deficiency with p53 deficiency. The results support the concept that TACC3 is a critical component of the centrosome/mitotic spindle apparatus and its absence triggers p53-mediated apoptosis. 相似文献
6.
Hoffmeyer MR Scalia R Ross CR Jones SP Lefer DJ 《American journal of physiology. Heart and circulatory physiology》2000,279(6):H2824-H2828
We investigated the effects of PR-39, a recently discovered neutrophil inhibitor, in a murine model of myocardial ischemia-reperfusion injury. Mice were given an intravenous injection of vehicle (n = 12) or PR-39 (n = 9) and subjected to 30 min of coronary artery occlusion followed by 24 h of reperfusion. In addition, the effects of PR-39 on leukocyte rolling and adhesion were studied utilizing intravital microscopy of the rat mesentery. The area-at-risk per left ventricle was similar in vehicle- and PR-39-treated mice. However, myocardial infarct per risk area was significantly (P < 0.01) reduced in PR-39 treated hearts (21.0 +/- 3.8%) compared with vehicle (47.1 +/- 4.8%). Histological analysis of ischemic reperfused myocardium demonstrated a significant (P < 0.01) reduction in polymorphonuclear neutrophil (PMN) accumulation in PR-39-treated hearts (n = 6, 34.3 +/- 1.7 PMN/mm(2)) compared with vehicle-treated myocardium (n = 6, 59.7 +/- 3.1 PMN/mm(2)). In addition, PR-39 significantly (P < 0.05) attenuated leukocyte rolling and adherence in rat inflamed mesentery. These results indicate that PR-39 inhibits leukocyte recruitment into inflamed tissue and attenuated myocardial reperfusion injury in a murine model of myocardial ischemia-reperfusion. 相似文献
7.
Bernard L Vaudaux P Huggler E Stern R Fréhel C Francois P Lew D Hoffmeyer P 《FEMS immunology and medical microbiology》2007,49(3):425-432
Polymorphonuclear neutrophils, a first line of defence against invading microbial pathogens, may be attracted by inflammatory mediators triggered by ultrahigh-molecular-weight polyethylene (UHMWPE) wear particles released from orthopaedic prostheses. Phagocytosis of UHMWPE particles by neutrophils may indirectly compromise their phagocytic-bactericidal mechanisms, thus enhancing host susceptibility to microbial infections. In an in vitro assay, pre-exposure of purified human neutrophils to UHMWPE micrometre- and submicrometre-sized wear particles interfered with subsequent Staphylococcos aureus uptake in a heterogeneous way, as assessed by a dual label fluorescence microscopic assay that discriminated intracellular rhodamine-labelled UHMWPE particles from fluorescein isothiocyanate-labelled S. aureus. Indeed, a higher percentage (44%) of neutrophils having engulfed UHMWPE particles lost the ability to phagocytize S. aureus, compared with UHMWPE-free neutrophils (<3%). Pre-exposure of neutrophils to UHMWPE wear particles did not impair but rather stimulated their oxidative burst response in a chemoluminescence assay. The presence of UHMWPE wear particles did not lead to significant overall consumption of complement-mediated opsonic factors nor decreased surface membrane display of neutrophil complement receptors. In conclusion, engulfment of UHMWPE wear particles led to inactivation of S. aureus uptake in nearly half of the neutrophil population, which may potentially impair host clearance mechanisms against pyogenic infections. 相似文献
8.
Jesper Hoffmeyer 《Biosemiotics》2008,1(2):169-190
Most bodies in this world do not have brains and the minority of animal species that do have brained bodies are descendents
from species with more distributed or decentralized nervous systems. Thus, bodies were here first, and only relatively late
in evolution did the bodies of a few species grow supplementary organs, brains, sophisticated enough to support a psychological
life. Psychological life therefore from the beginning was embedded in and served as a tool for corporeal life. This paper
discusses the semiotically controlled dynamics of bodily existence that has allowed the evolution of these seemingly ‘unnatural’
mental and even linguistic kinds of species. It is shown how the skin, on the one hand, makes us belong in the world, and
on the other hand, is part of the huge landscape of membranes across which the semiotic self incessantly must be reconstituted.
The discussion moves on to the intracellular world of signal transduction through which the activity of single cells are put
to service for bodily needs. The paper further considers the mechanisms behind homeostasis and the semiotics of the psycho-neuro-endocrine
integration in the body. The concept of semiotic emergence is introduced and a holistic marker hypothesis for why some animals
may have an experiential life is suggested.
相似文献
Jesper HoffmeyerEmail: |
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10.
Eurytemora americana and Acartia tonsa are the two most important copepods from the Bahía Blanca estuary plankton. For this study, 30 females were selected from recently preserved samples. Prosome length (PL), width (PW) and height (PH), urosome length (UL) and width (UW) measured in each female and subsequently the following ratios PL/PW, PL/PH, PW/PH and PL/UL were determined. Individual volumes for E. americana and A. tonsa females were estimated following the morphometric method in order to obtain individual biomass values. Regression tests were conducted for both species between individual volume and prosome length or width as independent variables, fitting data to a power model. Regression lines were compared through covariance analysis and single pair comparisons in order to evaluate the temporal behavior of the relationships. PL/UL was the best ratio for separating one species from the other. Average individual volume and std. error estimated for E. americana and A. tonsa were 0.0749 (±0.0097) mm3 and 0.0399 (±0.0049) mm3, respectively. Strong differences between both copepods morphometric variable and rate values were observed. A size and volume decrease was detected associated with higher temperatures and less phytoplankton available for food. According to R
2 values of regression lines prosome width and prosome length were good volume predictors on different dates for E. americana, however, prosome width was the best predictor on the majority of dates for A. tonsa. Differences in slopes and mean variances found between regression lines demonstrated seasonal variability. General regression equations between volume and PL or PW for each species could be derived. 相似文献