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排序方式: 共有10000条查询结果,搜索用时 31 毫秒
991.
Roza SJ van Lier PA Jaddoe VW Steegers EA Moll HA Mackenbach JP Hofman A Verhulst FC Tiemeier H 《Journal of the American Academy of Child and Adolescent Psychiatry》2008,47(3):264-272
OBJECTIVE: To determine whether intrauterine growth trajectories are associated with temperamental difficulties in infancy. METHOD: The Generation R Study is a population-based cohort study from fetal life onward. Size at different time points during gestation and growth trajectories, calculated on the basis of repeatedly measured fetal growth characteristics, were related to temperamental dimensions, assessed with the Infant Behavior Questionnaire-Revised, in 3,792 infants age 6 months. RESULTS: Birth weight, adjusted for gestational age, was negatively associated with activity level and duration of orienting. These associations disappeared after additional adjustment for maternal height, age, educational level, and national origin. Similarly, the negative associations between intrauterine total body weight gain and falling reactivity and activity level diminished after correction for maternal and child characteristics. After full adjustment, reduced fetal weight gain was only related to prolonged duration of orienting. Children scored 0.38 (95% confidence interval 0.09-0.68) points higher on duration of orienting per SD decrease in total body weight gain from mid-pregnancy to birth. CONCLUSIONS: After controlling for several genetic and socioeconomic status related factors, we found little indication of an association between intrauterine growth trajectories and temperamental difficulties in infants. 相似文献
992.
Schmidhuber SM Starr A Wynick D Kofler B Brain SD 《Journal of molecular neuroscience : MN》2008,34(2):149-155
The release of neuropeptides from primary sensory nerve fibers has been implicated in the modulation of local immune responses
in surface tissues, such as the skin and the gastrointestinal mucosa, thereby inducing neurogenic inflammation, which is characterized
by plasma extravasation and vasodilatation. In addition, cytokines, either alone or in conjunction with neuropeptides, initiate
recruitment of immunocompetent cells such as neutrophils during the initial phases of inflammation. Growing evidence suggests
that the neuropeptide galanin plays an important role in skin immune defense and pathophysiology. In this paper, we report
that adult mice carrying a loss-of-function mutation in the galanin gene (galanin knockout, Gal KO) demonstrate an absence
of the normal neurogenic inflammatory response, upon treatment of the skin either with the vanilloid receptor 1 agonist capsaicin
or noxious heat. Furthermore, a lack of an acute inflammatory edema induced by coinjection of substance P and calcitonin gene-related
peptide was observed. In addition, Gal KO animals also exhibit a deficit in neutrophil accumulation in the skin after exposure
to noxious heat, carrageenin, or tumor necrosis factor alpha. These data indicate that Gal KO mice demonstrate abnormal neurogenic
inflammatory responses in murine skin compared to strain-matched wild-type mice. 相似文献
993.
Althaus HH Klöppner S Klopfleisch S Schmitz M 《Journal of molecular neuroscience : MN》2008,35(1):65-79
Oligodendrocytes met neurotrophins in the early 1990s of the last century. Since then, their relationship underwent functional ups and downs partially dependent on the developmental stage of the oligodendroglial cells and the species, from which the cells were derived. This review provides a brief overview of oligodendroglial cells and neurotrophins, characterizes neurotrophin signaling during oligodendroglial development, and discusses the significance of proneurotrophins and sortilin for oligodendroglial death and survival. Furthermore, data are provided that TrkA, the tyrosine kinase competent NGF receptor, is localized to caveolincontaining microdomains on the oligodendroglial plasma membrane; an interplay of caveolin and NGF signaling via TrkA might be of functional importance. Finally, experimental evidence of studies is presented which support the idea that neurotrophins are promising candidates for improving oligodendroglial regeneration and remyelination. 相似文献
994.
Due to learning processes originally neutral stimuli become drug-associated and can activate an implicit drug memory, which leads to a conditioned arousing 'drug-seeking' state. This condition is accompanied by specific psychophysiological responses. The goal of the present study was the analysis of changes in cortical and peripheral reactivity to cannabis as well as alcohol-associated pictures compared with emotionally significant drug-unrelated and neutral pictures in long-term heavy cannabis users. Participants were 15 chronic heavy cannabis users and 15 healthy controls. Verbal reports as well as event-related potentials of the electroencephalogram and skin conductance responses were assessed in a cue-reactivity paradigm to determine the psychophysiological effects caused by drug-related visual stimulus material. The evaluation of self-reported craving and emotional processing showed that cannabis stimuli were perceived as more arousing and pleasant and elicited significantly more cannabis craving in cannabis users than in healthy controls. Cannabis users also demonstrated higher cannabis stimulus-induced arousal, as indicated by significantly increased skin conductance and a larger late positivity of the visual event-related brain potential. These findings support the assumption that drug-associated stimuli acquire increased incentive salience in addiction history and induce conditioned physiological patterns, which lead to craving and potentially to drug intake. The potency of visual drug-associated cues to capture attention and to activate drug-specific memory traces and accompanying physiological symptoms embedded in a cycle of abstinence and relapse – even in a 'so-called' soft drug – was assessed for the first time. 相似文献
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998.
Expression of ectonucleotidase CD39 by Foxp3+ Treg cells: hydrolysis of extracellular ATP and immune suppression
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999.
Fischer K Hoffmann P Voelkl S Meidenbauer N Ammer J Edinger M Gottfried E Schwarz S Rothe G Hoves S Renner K Timischl B Mackensen A Kunz-Schughart L Andreesen R Krause SW Kreutz M 《Blood》2007,109(9):3812-3819
A characteristic feature of tumors is high production of lactic acid due to enhanced glycolysis. Here, we show a positive correlation between lactate serum levels and tumor burden in cancer patients and examine the influence of lactic acid on immune functions in vitro. Lactic acid suppressed the proliferation and cytokine production of human cytotoxic T lymphocytes (CTLs) up to 95% and led to a 50% decrease in cytotoxic activity. A 24-hour recovery period in lactic acid-free medium restored CTL function. CTLs infiltrating lactic acid-producing multicellular tumor spheroids showed a reduced cytokine production. Pretreatment of tumor spheroids with an inhibitor of lactic acid production prevented this effect. Activated T cells themselves use glycolysis and rely on the efficient secretion of lactic acid, as its intracellular accumulation disturbs their metabolism. Export by monocarboxylate transporter-1 (MCT-1) depends on a gradient between cytoplasmic and extracellular lactic acid concentrations and consequently, blockade of MCT-1 resulted in impaired CTL function. We conclude that high lactic acid concentrations in the tumor environment block lactic acid export in T cells, thereby disturbing their metabolism and function. These findings suggest that targeting this metabolic pathway in tumors is a promising strategy to enhance tumor immunogenicity. 相似文献
1000.