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11.
Uffe A. Brodthagen Knud NØrregaard Hansen Jens Bjerre Knudsen Robert Jordal Ole Kristensen Poul -Erik Paulev 《European journal of applied physiology》1985,53(4):334-338
Summary 20 male elite long distance runners were compared to a control group of blood donors to determine the effect of training on red blood cells. The acute effects of exercise on red cells were investigated in 11 of the runners following a race of 15–30 km. The runners had elevated resting values of red cell 2,3-DPG (P<0.05) and mean cell volume (P<0.01); blood Hb and ATP were not different from concentrations in the control group. The red cell status of the athletes may be explained by an increased proportion of young erythrocytes in runners. No statistically significant changes in red cell 2,3-DPG, ATP, mean cell volume or blood Hb were found post exercise. 相似文献
12.
Frits Ørskov Ida Ørskov Doyle J. Evans Jr. R. Bradley Sack David A. Sack Torkel Wadström 《Medical microbiology and immunology》1976,162(2):73-80
106 enterotoxigenicEscherichia coli strains from children and adults from many parts of the world were serotyped for O and H antigens. Some OH types,i.e. O6H16, O8H9, O15H11, O25H42, O78H11 and O78H12, were found repeatedly from different geographical locations. Some of these OH serotypes were only found rarely among more than 20000E. coli strains collected over many years from different locations and sources. It is suggested that these special OH serotypes represent clones which have been selected to the special conditions in the small intestine and selected to carry the plasmids necessary to provoke diarrhoea. 相似文献
13.
The completion of the human genome project and the construction of single nucleotide polymorphism (SNP) maps have lead to significant efforts to find SNPs that can be linked to pathophysiology. In silico models of complete biochemical reaction networks relate a cell's individual reactions to the function of the entire network. Sequence variations can in turn be related to kinetic properties of individual enzymes, thus allowing an in silico model-driven assessment of the effects of defined SNPs on overall cellular functions. This process is applied to defined SNPs in two key enzymes of human red blood cell metabolism: glucose-6-phosphate dehydrogenase and pyruvate kinase. The results demonstrate the utility of in silico models in providing insight into differences between red cell function in patients with chronic and nonchronic anemia. In silico models of complex cellular processes are thus likely to aid in defining and understanding key SNPs in human pathophysiology. 相似文献
14.
Øivind Øines Thomas Schram 《Acta parasitologica / Witold Stefański Institute of Parasitology, Warszawa, Poland》2008,53(1):93-105
Two mitochondrial and one nuclear genetic marker were used to study the phylogenetic position of the two reported CO1-genotypes
of Caligus elongatus in a group of closely related caligid parasites. Molecular analysis of the two mitochondrial genes (CO1 and 16S), indicate
genetic distances of the two C. elongatus genotypes in the lower range of distances previously reported between other crustacean species, but higher than comparable
reported within-species differences. Analyses of nuclear 18S sequences indicate no detectable differentiation between these
genotypes, but may be due to expected differences in the resolution of these genetic markers. Investigation of two of three
selected morphological characters reveals phenotypes supporting the division based on the molecular division. The species
status on the two C. elongatus genotypes cannot be drawn conclusively, although the molecular and morphological data presented here suggests the presence
of sibling species. 相似文献
15.
Dahle MK Øverland G Myhre AE Stuestøl JF Hartung T Krohn CD Mathiesen Ø Wang JE Aasen AO 《Infection and immunity》2004,72(10):5704-5711
Sepsis caused by gram-positive bacteria lacking lipopolysaccharide (LPS) has become a major and increasing cause of mortality in intensive-care units. We have recently demonstrated that the gram-positive-specific bacterial cell wall component lipoteichoic acid (LTA) stimulates the release of the proinflammatory cytokines in Kupffer cells in culture. In the present study, we have started to assess the signal transduction events by which LTA induces the production of tumor necrosis factor alpha (TNF-alpha), interleukin-6 (IL-6), and the anti-inflammatory cytokine IL-10 in rat Kupffer cells. LTA was found to trigger phosphorylation of mitogen-activated protein kinases (MAPK) (p38 MAPK and ERK 1/2) and protein kinase B (PKB). Compared to LPS, LTA was more potent in inducing PKB phosphorylation after 40 min, although we found that the cytokine responses were similar. For both bacterial molecules, blocking phosphatidylinositol 3-kinase (PI3-K; Ly294002) or Janus kinase 2 (JAK-2; AG490) particularly affected the induction of IL-6 and IL-10 release, whereas TNF-alpha levels were strongly reduced by inhibition of Src family tyrosine kinases (PP2). All three cytokines were reduced by inhibition of p38 MAPK (SB202190) or the broad-range tyrosine kinase inhibitor genistein, whereas IL-6 release was particularly blocked by inhibition of ERK 1/2 (PD98059). Divergences in the regulatory pathways controlling TNF-alpha, IL-10, and IL-6 production in Kupffer cells following LPS or LTA stimulation may create a basis for understanding how the balance between pro- and anti-inflammatory cytokines is regulated in the liver following infections by gram-positive or gram-negative bacteria. 相似文献
16.
Hans-JØrgen Malling 《Clinical reviews in allergy & immunology》1992,10(3):213-236
Conclusion The problems of elucidating the role of mold spores in allergy are related to both an absence of detailed information about
allergen exposure, and lack of standardized allergen extracts. Provided qualitatively and quantitatively optimal extracts
are available, the IgE-diagnostic tests are of equal value in diagnosing mold sensitization, as with other aeroallergens.
In the opinion of the author, the specific diagnosis represents the combination of demonstrated IgE reactivity (using diagnostic
tests) and clinical symptoms related to exposure to the causative allergen. In order to diagnose organ-specific disease, an
unequivocally positive challenge in the relevant shock organ is essential. The rational approach to diagnosing mold allergy
is, based on the clinical history, to use skin test as the primary screening test. SPT has the highest sensitivity (few false
negative reactions) and, compared to ICT, few irrelevant positive reactions, and should consequently be used to screen for
IgE sensitization in the diagnostic workup. Because of the lower sensitivity, RAST is not optimal as the initial test, but
as a result of high specificity (few false positive reactions) it is optimal as a confirmatory test for the presence of specific
IgE. The clinical relevance of the IgE sensitization should be confirmed by reevaluating the history to ensure that the patients
do in fact have symptoms caused by the allergen (Table 2). Challenge tests are normally indicated only if the diagnosis of
allergen sensitization implies therapeutic interventions, such as allergen-specific immunotherapy. 相似文献
17.
Melissa C. Kanar Dwain L. Thiele Monika Østensen Peter E. Lipsky 《Journal of clinical immunology》1988,8(1):69-79
Natural killer (NK)-like activity against a renal carcinoma cell line, Cur, was assessed. There was no spontaneous killing of Cur cells by human peripheral blood mononuclear cells in 4-hr assays. Cur killing was observed in 18-hr assays, but the magnitude of killing was variable and always markedly less than that against K562. Cur killing was mediated by a nonadherent, nonphagocytic lymphocyte, the activity of which could be modulated both positively and negatively by monocytes or their products. Preincubation of effectors with monocyte supernatant, interleukin 1 (IL-1), -interferon (IFN), or interleukin 2 (IL-2) greatly increased the magnitude of Cur killing and accelerated the kinetics of lysis. The addition of prostaglandin E2 (PGE2) duringin vitro activation of NK by IL-2 profoundly inhibited subsequent Cur lysis, whereas only minimal inhibition of K562 lysis was noted. However, following activation with IL-2, lysis of Cur targets was less sensitive to the inhibitory effects of PGE2. Removal of Leu 11b(+), OKM1(+), orl-leucylleucine methyl ester-sensitive cells markedly decreased both Cur and K562 lysis. Moreover, CD16(+) cells purified with the fluorescence-activated cell sorter were found to mediate Cur killing. Whereas Cur and K562 lysis is mediated by phenotypically similar effector cells, the present studies demonstrate that the cytotoxic functions defined by the ability to lyse these two targets differ in response to a variety of immunoregulatory stimuli. 相似文献
18.
Use of robotized DNA isolation and real-time PCR to quantify and identify close correlation between levels of Neisseria meningitidis DNA and lipopolysaccharides in plasma and cerebrospinal fluid from patients with systemic meningococcal disease
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Øvstebø R Brandtzaeg P Brusletto B Haug KB Lande K Høiby EA Kierulf P 《Journal of clinical microbiology》2004,42(7):2980-2987
The present study, using robotized DNA isolation and quantitative PCR based on the Neisseria meningitidis-specific capsular transport A gene, demonstrates the ease, rapidity, specificity, and sensitivity of quantifying neisserial DNA in plasma (n = 65) and cerebrospinal fluid (CSF) (n = 12) from patients with systemic meningococcal disease. We found a close correlation between the levels of neisserial DNA and lipopolysaccharides in plasma (r = 0.905) and in CSF (r = 0.964). The median concentration of neisserial DNA in plasma in 23 patients with persistent shock was 2 x 10(7) copies/ml, versus <10(3) copies/ml in 42 nonshock patients. Furthermore, quantitative PCR made possible estimates of the total number of meningococci in plasma, as opposed to conventional blood cultures, suggesting about 1,000 dead meningococci for every viable bacterium. Finally, with logistic regression analyses, neisserial DNA may predict a patient's disease severity and outcome at hospital admission. The number of meningococci in plasma and CSF appears to be the main determinant of the lipopolysaccharide levels, clinical presentation, and outcome. 相似文献
19.
For a drug with concentration-dependent serum protein binding, the unbound fraction of drug decreases during the drug elimination process. The clearance of the drug at a given blood flow rate is lower than would be expected from the observed unbound fraction in venous blood from a noneliminating organ. Based on both the well-stirred and parallel tube models, simulations demonstrated that consideration of concentration-dependent binding during drug elimination is important when the intrinsic clearance is higher than the blood flow and when the unbound drug concentration is much greater than the dissociation equilibrium constant of the binding complex.Supported in part by Grant GM 28423 from the National Institutes of General Medical Sciences, NIH. 相似文献
20.
Nes Ragnhild Bang Yu Baeksan Hansen Thomas Vedaa Øystein Røysamb Espen Nilsen Thomas S. 《Quality of life research》2022,31(8):2295-2305
Quality of Life Research - We examined multidimensional, heterogeneous reactions to the COVID-19 pandemic and associated measures to provide further insights into the developmental processes of... 相似文献