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101.
A double-blind study of the tryptophan depletion (TD) challenge was performed on a sample consisting of 20 patients with a major depressive disorder in clinical remission after citalopram treatment. TD was induced by the intake of 43 g of an amino acid mixture containing the five large neutral amino acids. The control group received the same mixture, to which 2.3 g tryptophan had been added. Five of the 12 challenged patients showed a worsening of depressive symptoms during the day of the test. In contrast, there was no mood alteration in the eight control patients. Baseline cortisol levels were significantly higher in responders to TD compared to those in non-responders and controls. Platelet serotonin-receptor function and plasma prolactin levels were correlated. There was a significant positive correlation in the baseline data between rated mood state and plasma cortisol and a significant inverse correlation between related mood state and plasma tryptophan concentration. Thus low mood appeared to be associated with low serotonin precursor availability as well as with high cortisol levels.  相似文献   
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The P-selectin glycoprotein ligand-1 (PSGL-1) is a high-affinity ligand of P-selectin on myeloid cells and certain subsets of lymphoid cells. We generated the rat monoclonal antibody (MoAb) 2PH1 that recognizes an epitope within the first 19 amino acids at the N-terminus of the processed form of mouse PSGL-1. This antibody blocks attachment of mouse myeloid cells to P-selectin under both static and flow conditions. Intravenous administration of saturating amounts of 2PH1 reduced the number of rolling leukocytes in venules of the acutely exposed mouse cremaster muscle by 79% (+/-5.7%), whereas an anti-P-selectin MoAb reduced it completely. Examining the effect of the MoAb 2PH1 on the recruitment of neutrophils into chemically inflamed mouse peritoneum showed that blocking PSGL-1 inhibited neutrophil accumulation in the peritoneum by 82% (+/-7%) at 2 hours and by 59% (+/-7.9%) at 4 hours after stimulation. A similar effect was seen with the MoAb against P-selectin. Simultaneous administration of both antibodies at the 4-hour time point blocked neutrophil accumulation by 86% (+/-4.2%), arguing for an additional partner molecule for PSGL-1 besides P-selectin. This is the first demonstration of the importance of PSGL-1 in the recruitment of mouse neutrophils into inflamed tissue.  相似文献   
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A variety of neurotransmitter receptor changes occur after a course of electroconvulsive seizures (ECS) in rats, including an increased density of adenosine A1 sites. Adenosine antagonism has been related to the proconvulsant action of methylxanthines such as caffeine. We determined tonic-clonic seizure duration in rats given ECS with caffeine (0-175 mg/kg, IP) after a course of one or six daily ECS. A single day of ECS did not affect the dose-dependent proconvulsant action of caffeine. After six daily ECS, the proconvulsant action of caffeine was reduced. After nine daily ECS, an A1 antagonist (8-cyclopentyl-1,3-dipropylxanthine) and an A2A antagonist (1-allyl-3,7-dimethyl-8-p-sulfophenylxanthine) showed reduced proconvulsant activity. The results suggest that the reduced proconvulsant action of caffeine after chronic ECS depends on adenosine antagonism.  相似文献   
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欢迎参加Bauma+mining2004德国机械设备制造商协会有3000个会员,她不但是德国最大的工业联合会,也是欧洲最大的机械及设备制造网络。德国机械设备制造商协会已具有百年的历史,下属37个专业协会,建设和建材机械设备制造专业协会就是其中之一。30年以来,德国机械设备制造商协会为Bauma提供了理念上的支持,Bauma发展到今天,已经成为世界上(施工设备行业)最大的投资贸易展览会。2004年,我们将在展览会上增加采矿机械,使参展商和参观者有更大的收获。我们热情地邀请大家参加Bauma + min-ing 2004展览会。Bauma和Bauma mining展区精确地按照产…  相似文献   
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Quality control of medical imaging systems is performed using dedicated phantoms. As the imaging systems are more and more digital, adequate image processing methods might help to save evaluation time and to receive objective results. The developed software package OPTIMAGE is focusing on this with a central approach: On one hand, OPTIMAGE provides a framework, which includes functions like database integration, DICOM data sources, multilingual user interface and image processing functionality. On the other hand, the test methods are implemented using modules which are able to process the images automatically for the common imaging systems. The integration of statistics and reporting into this environment is paramount: This is the only way to provide these functions in an interactive, user-friendly way. These features enable the users to discover degradation in performance quickly and document performed measurements easily.  相似文献   
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The C-LytA protein constitutes the choline-binding module of the LytA amidase from Streptococcus pneumoniae. Owing to its affinity for choline and analogs, it is regularly used as an affinity tag for the purification of proteins in a single chromatographic step. In an attempt to build a robust variant against thermal denaturation, we have engineered several salt bridges on the protein surface. All the stabilizing mutations were pooled in a single variant, C-LytAm7, which contained seven changes: Y25K, F27K, M33E, N51K, S52K, T85K and T108K. The mutant displays a 7 degrees C thermal stabilization compared with the wild-type form, together with a complete reversibility upon heating and a higher kinetic stability. Moreover, the accumulation of intermediates in the unfolding of C-LytA is virtually abolished for C-LytAm7. The differences in stability become more evident when the proteins are bound to a DEAE-cellulose affinity column, as most of wild-type C-LytA is denatured at approximately 65 degrees C, whereas C-LytAm7 may stand temperatures up to 90 degrees C. Finally, the change in the isoelectric point of C-LytAm7 enhances its solubility at acidic pHs. Therefore, C-LytAm7 behaves as an improved affinity tag and supports the engineering of surface salt bridges as an effective approach for protein stabilization.  相似文献   
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