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31.
'Pena-Shokeir syndrome' in a newborn male infant 总被引:1,自引:0,他引:1
JB Mailhes K Lancaster MJ Bourgeois ID Sanusi 《Canadian Metallurgical Quarterly》1977,131(12):1419-1420
32.
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Thirty children seen between 1954 and 1970 with the diagnosis of anorexia nervosa were contacted between five and twenty years after initial treatment. Patients outcomes in terms of education, weight in adulthood, medical problems, marriage, psychiatric treatment, and recurrence of anorexia were surveyed. Results corroborate those of earlier studies suggesting that adjustment in adulthood is related to personality type. 相似文献
34.
B Siegmund A Eigler G Hartmann U Hacker S Endres 《Canadian Metallurgical Quarterly》1998,20(1-3):57-69
The aim of the present study was to investigate the role of cAMP in enhanced IL-10 synthesis in human mononuclear cells. Adrenaline is known to act via the alpha- and beta-adrenergic receptors which are coupled to adenylyl cyclase. The effects of cAMP elevation on IL-10 synthesis were studied at the protein level by ELISA and at the level of mRNA by RT/PCR. In this in vitro model adrenaline enhanced the LPS-induced synthesis of IL-10 with parallel suppression of TNF synthesis. These effects were demonstrated both at the protein level and the level of mRNA. To analyze the role of cAMP we antagonized this effect by application of (Rp)-cAMPS, a diastereomer of adenosine-3',5'-cyclic phosphorothioate, known to inhibit competitively the cAMP-induced activation of protein kinase A. Simultaneous addition of adrenaline and (Rp)-cAMPS led to a reversal of IL-10 synthesis to values induced by LPS stimulation alone. The kinetic analysis in LPS-stimulated mononuclear cells revealed a significant delay of IL-10 synthesis starting after 7 h compared with TNF synthesis which showed the first significant increase at 90 min. Finally, the combination of adrenaline and exogenous IL-10 led to a more pronounced suppression of TNF synthesis after LPS stimulation compared to suppression by IL-10 or adrenaline alone. The present results suggest the role of protein kinase A activation for adrenaline-induced IL-10 synthesis in human mononuclear cells. Additionally, based on the kinetic analysis and further experiments described in the literature, endogenous IL-10 could contribute to the adrenaline-induced suppression of TNF synthesis after prolonged incubation. These in vitro results could explain the suppression of TNF plasma concentration after parallel infusion of LPS and epinephrine compared to LPS infusion alone as has been demonstrated in a first human study. 相似文献
35.
Mello LV; van Aalten DM; Findlay JB 《Protein engineering, design & selection : PEDS》1997,10(4):381-387
This paper documents the first essential dynamics analysis of ras protein
ligands and of the protein itself, showing important features of their
dynamic properties. Essential dynamics analysis of 300 ps of full solvent
molecular dynamics simulations revealed differences in structure and
dynamics between GDP- and GTP-bound forms of H-ras-p21. Regions in the
protein which exhibited a structural shift correspond to the switch regions
described previously. Differences in dynamics between H-ras-p21 GDP and
H-ras-p21 GTP may be related to interactions of ras with GAP and its
receptor and effector. Molecular dynamics of free GDP (in the absence of
protein) were performed in water for 2 ns and analysed using essential
dynamics. The conformations of GDP and GTP when bound to the protein were
compared with free GDP, revealing that the ligands bind to the protein in
an energetically unfavourable conformation. GDP and GTP molecules from
various other protein crystal structures were also analysed. These ligands
adopt similar conformations to those seen in H-ras-p21.
相似文献
36.
We construct two optimal Newton–Secant like iterative methods for solving nonlinear equations. The proposed classes have convergence order four and eight and cost only three and four function evaluations per iteration, respectively. These methods support the Kung and Traub conjecture and possess a high computational efficiency. The new methods are illustrated by numerical experiments and a comparison with some existing optimal methods. We conclude with an investigation of the basins of attraction of the solutions in the complex plane. 相似文献
37.
Claudia Kretzschmar Robert Siegmund Dietmar Müller 《The Journal of supercomputing》2003,26(2):185-203
In this paper, an approach to the implementation of digital systems is presented which utilizes dynamic hardware reconfiguration in order to automatically minimize the power dissipated on module interconnections such as system buses during system run time. Reduction of power dissipation is achieved by means of an activity-reducing system bus encoding technique. Encoder and decoder are implemented with dynamically reconfigured code tables which contain a transition minimizing code that is periodically recomputed during run time of the system in order to adapt to variations in the statistical parameters of the encoded data stream. We present the theoretical basics and an efficient implementation of a corresponding coder-decoder system. Experimental results showed a reduction in bus transition activity of up to 41%. 相似文献
38.
39.
Administration of phenobarbital (60 mg/kg) daily for 4 days to male rabbits resulted in induction of renal cytochrome P-450 (3.5-fold) and a corresponding increase in ethoxycoumarin-O-deethylase and benzphetamine-N-demethylase activity (17- and 4-fold, respectively). Kidney weight to body weight ratio and renal ethoxyresorufin-O-deethylase were not affected by phenobarbital pretreatment. Numerous focal areas of proliferation of smooth endoplasmic reticulum (SER) were evident in proximal tubule cells from phenobarbital treated rabbits while proximal tubular cells from control rabbits had only small and sparcely located aggregates of SER. Phenobarbital-induced SER proliferation was specifically localized to the S3 segment of the proximal tubule. Proliferation was not observed in S2 cells of the proximal tubule, cells of Henle's loop, distal tubules, or collecting tubules in rabbits pretreated with phenobarbital. These data demonstrate the biochemical heterogeneity of cell types within the proximal tubules of rabbits. Furthermore, induction of mixed-function oxidases specifically in S3 cells of the proximal tubule may be of toxicological significance in the metabolic activation of certain nephrotoxicants. 相似文献
40.
T Scheibel HI Siegmund R Jaenicke P Ganz H Lilie J Buchner 《Canadian Metallurgical Quarterly》1999,96(4):1297-1302
Hsp90, an abundant heat shock protein that is highly expressed even under physiological conditions, is involved in the folding of key molecules of the cellular signal transduction system such as kinases and steroid receptors. It seems to contain two chaperone sites differing in substrate specificity. Binding of ATP or the antitumor drug geldanamycin alters the substrate affinity of the N-terminal chaperone site, whereas both substances show no influence on the C-terminal one. In wild-type Hsp90 the fragments containing the chaperone sites are connected by a highly charged linker of various lengths in different organisms. As this linker region represents the most striking difference between bacterial and eukaryotic Hsp90s, it may be involved in a gain of function of eukaryotic Hsp90s. Here, we have analyzed a fragment of yeast Hsp90 consisting of the N-terminal domain and the charged region (N272) in comparison with the isolated N-terminal domain (N210). We show that the charged region causes an increase in the affinity of the N-terminal domain for nonnative protein and establishes a crosstalk between peptide and ATP binding. Thus, the binding of peptide to N272 decreases its affinity for ATP and geldanamycin, whereas the ATP-binding properties of the monomeric N-terminal domain N210 are not influenced by peptide binding. We propose that the charged region connecting the two chaperone domains plays an important role in regulating chaperone function of Hsp90. 相似文献