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71.
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A glutathione-S-transferase-src-homology domain 2 (GST-SH2) fusion protein was employed to identify molecules interacting with the protein tyrosine kinase p59fyn. Among several proteins which bound to the fyn SH2 domain in lysates of human Jurkat T lymphocytes, α- and β-tubulin were identified by N-terminal sequencing. Further analysis established that α-tubulin exists as a tyrosine-phosphorylated protein in Jurkat cells, where it interacts with p59fyn, but not with p56lck. By contrast, in untransformed resting human T lymphocytes α-tubulin is not detectable as a tyrosine phosphorylated protein. However, following T cell activation, it becomes rapidly phosphorylated on tyrosine residues and subsequently associates with the SH2 domain of fyn. Interestingly, constitutively tyrosine-phosphorylated α-tubulin that is able to interact with the fyn-SH2 domain is expressed in peripheral blood T lymphoblasts isolated from leukemic patients in the absence of external stimulation.  相似文献   
73.
Tumor necrosis factor (TNF) and interleukin-(IL)-18 are important mediators of neuroinflammation after closed head injury (CHI). Both mediators have been previously found to be significantly elevated in the intracranial compartment after brain injury, both in patients as well as in experimental model systems. However, the interrelation and regulation of these crucial cytokines within the injured brain has not yet been investigated. The present study was designed to assess a potential regulation of intracranial IL-18 levels by TNF based on a clinical study in head-injured patients and an experimental model in mice. In the first part, we investigated the interrelationship between the daily TNF and IL-18 cerebrospinal fluid levels in 10 patients with severe CHI for up to 14 days after trauma. In the second part of the study, the potential TNF-dependent regulation of intracerebral IL-18 levels was further characterized in an experimental set-up in mice: (1) in a standardized model of CHI in TNF/lymphotoxin-alpha gene-deficient mice and wild-type (WT) littermates, and (2) by intracerebro-ventricular injection of mouse recombinant TNF in WT C57BL/6 mice. The results demonstrate an inverse correlation of intrathecal TNF and IL-18 levels in head-injured patients and a TNF-dependent inhibition of IL-18 after intracerebral injection in mice. These findings imply a potential new anti-inflammatory mechanism of TNF by attenuation of IL-18, thus confirming the proposed "dual" function of this cytokine in the pathophysiology of traumatic brain injury.  相似文献   
74.
It can be shown that the procedure for representing the effect of the vagal innervation of the heart introduced by Brown and Eccles in 1934 distorts the actual course of the inhibitory effect. A corrected procedure is proposed. It is stressed that cycle phase specificity of the stimulation can be studied only by drawing different curves representing the course of the vagal effect for different times of stimulation within the cardiac cycle.  相似文献   
75.
Previous studies of the TCR chain gene have located promoterelements 5' to the start of the various V genes. The only fullycharacterized enhancer for the entire chain gene (V, J andC genes) has been located {small tilde}3 kb from the 3' endof C. We now report the existence of additional regulatory elementslocated in the introns of several murine V genes (V1, V3 andVB6.2.16). In the case of V1, this element appears to be a promoterwith bidirectional activity that is not T cell specific. Interestingly,upstream of the promoter in the antisense strand, an open readingframe has been found that codes for a small molecular weightprotein ({small tilde}60 amino acids) that contains a prollne-richregion and a tyrosine-isoleucine motif that has homology toIgß (the B29 gene product). A rabbit antiserum madeagainst this sequence has confirmed its existence by Westernblot and immunoprecipitation. Thus this V1 intronic promoterhas the potential not only to induce the formation of a truncatedV1 gene product, but also regulates the expression of a smallmolecular weight protein that may be involved in lymphocyteantigen receptor signaling. The activity of this promoter isregulated by changes in intracellular calcium. In the presenceof ionomycin the promoter is down-regulated in the sense directionand its activity is enhanced in the antisense direction. Thisresult suggests that this promoter can act differentially toproduce two very different gene products. The bidirectionalV1 promoter appears to be the first in the Ig superfamily toinduce potentially functional proteins in both directions.  相似文献   
76.
ObjectiveAssess how intuitive eating relates to dietary intake.MethodsSurvey data were collected in Project Eating and Activity in Teens and Young Adults, the fourth wave of a longitudinal cohort study (weighted n = 1,830, 49% women; mean age = 31 years). Intuitive eating was assessed using a 7-item scale adapted from the Intuitive Eating Scale and Intuitive Eating Scale-2. Dietary intake was measured via a semiquantitative food frequency questionnaire. Mean servings were stratified by gender and intuitive eating quartiles and adjusted for sociodemographic characteristics and caloric intake.ResultsWomen and men in the top intuitive eating quartile consumed 0.6–0.3 servings more fruit and 0.4–0.6 servings more vegetables daily, respectively, compared with the bottom quartile, whereas men in the top quartile also consumed 0.6 servings fewer whole grains (all P < 0.05) than the bottom quartile.Conclusions and ImplicationsIntuitive eating shows promise as a healthier alternative to practices such as dieting.  相似文献   
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International Urology and Nephrology - To test the value of preoperative and postoperative cystatin C (CysC) as a predictor on kidney function after partial (PN) or radical nephrectomy (RN) in...  相似文献   
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Alcohol abuse after liver transplantation can seriously impact graft and patient survival. However, to date, there is no defined standard procedure to identify patients consuming alcohol after liver transplantation. The aim of this study was to analyze the diagnostic value and clinical impact of routinely measured urinary ethyl glucuronide (uEtG) – a metabolite of ethanol – in patients after liver transplantation. Data of 362 consecutive patients after liver transplantation who visited the University Hospital of Tuebingen for outpatient follow-up were analyzed. Forty-eight patients (13%) displayed positive uEtG results. The uEtG positive group contained significantly more patients with pretransplant alcoholic liver disease. However, two thirds of the uEtG positive patients had no history of pretransplant alcoholic liver disease. Several clinical parameters were significantly associated with positive uEtG. In order to enable a more cost-effective application of uEtG in the future, a clinical risk score was developed (specificity 0.95). In conclusion, routine testing for uEtG reveals a considerable percentage of patients practicing alcohol intake after liver transplantation. Application of our proposed risk score could help focusing uEtG testing on patients at risk.  相似文献   
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