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991.
A Wolthuis RB Landewé PH Theunissen LW Westerhuis 《Canadian Metallurgical Quarterly》1998,12(5):1233-1235
The diagnosis chylothorax is based on a chemical analysis of the pleural effusion. According to the literature, this analysis can be rather straightforward, comprising measurements of triglycerides, chylomicrons, and cholesterol. In this report we present an autopsy case that alerted us to interpret these results critically. Although the laboratory tests of the pleural effusion in this patient with parenteral nutrition suggested chylothorax, additional tests (potassium (11.3 mmol.L(-1)) and glucose (128 mmol.L(-1)) proved otherwise. Comparison of the pleural effusion analysis and the content of the parenteral nutrition led to the final conclusion that the effusion was due to a leakage of parenteral nutrition instead of chylothorax. We therefore suggest adding glucose and potassium measurements to the biochemical work-up of a patient under suspicion of chylothorax. 相似文献
992.
993.
DA Bennett L Phun JF Polk SA Voglino V Zlotnik RB Raffa 《Canadian Metallurgical Quarterly》1998,32(11):1201-1208
OBJECTIVE: A developmental-ecological model was used to explore the psychological adjustment and peer social competencies of maltreated preschool children. METHOD: Enhanced research methods were used that included verification of maltreatment status, multiple-variable matching of comparison children, and contextually relevant assessment. One hundred eight Head Start children, of whom 54 were maltreated, participated. Assessment of social functioning included measurement of peer play interactions, global social skills, peer sociometrics, and teacher and parent ratings of behavior problems. RESULTS: Findings indicated that maltreated children were significantly less interactive in peer play and overall exhibited less self-control and interpersonal skill in social interactions than nonmaltreated children. In addition, maltreated children were more likely than their nonmaltreated peers to receive low sociometric ratings and were found by both teachers and parents to display more internalizing behavior problems than comparison children. CONCLUSIONS: These findings indicate the importance of using developmentally sensitive research methods to inform contextually relevant interventions. 相似文献
994.
The membrane-bound state of the gene 9 minor coat protein of bacteriophage M13 was studied in various membrane-mimicking systems, including organic solvents, detergent micelles, and phospholipid bilayers. For this purpose we determined the conformational and aggregational properties of the chemically synthesized protein by CD, FTIR, and HPSEC. The protein appears to be in a monomeric or small oligomeric alpha-helical state in TFE but adopts a mixture of alpha-helical and random structure after subsequent incorporation into SDS or DOPG. When solubilized by sodium cholate, however, the protein undergoes a transition in time into large aggregates, which contain mainly beta-sheet conformation. The rate of this beta-polymerization process was decreased at lower temperature and higher concentrations of sodium cholate. This aggregation was reversed only upon addition of high concentrations of the strong detergent SDS. By reconstitution of the cholate-solubilized protein into DOPG, it was found that the state of the protein, whether initially alpha-helical monomeric/oligomeric or beta-sheet aggregate, did not change. On the basis of our results, we propose that the principal conformational state of membrane-bound gene 9 protein in vivo is alpha-helical. 相似文献
995.
Domain 1 of CD2 (CD2.D1) forms a conventional Ig fold stabilised by non-covalent antiparallel contacts between beta-strands. Removing two residues from the middle of the protein sequence, where the polypeptide chain normally folds back upon itself, stabilises an open conformation. In this modified molecule, the optimum evolved contacts between side-chains can only be satisfied through the antiparallel association of two chains to create a symmetrical pair of pseudo-domains. Here, we describe the dynamics of the switch between monomeric and dimeric states and demonstrate the extension of this novel underlying principle to trimer and tetramer formation. The ability of a protein molecule to form higher-order antiparallel structures is reminiscent of the behaviour of hairpins, duplexes, three-way and Holliday junctions in DNA. 相似文献
996.
CA Palmer JD Geyer JM Keating F Gilliam RI Kuzniecky RB Morawetz EM Bebin 《Canadian Metallurgical Quarterly》1999,40(2):242-247
The role of the glutamate receptor GluR3 in Rasmussen's encephalitis is actively under investigation. Autoimmune processes with this receptor as the target are currently theorized. We provide an additional case of pathologically proved Rasmussen's encephalitis (with concomitant cortical dysplasia) in the presence of antibodies against the GluR3 receptor. 相似文献
997.
DP Slovut JC Wenstrom RB Moeckel RF Wilson JW Osborn JH Abrams 《Canadian Metallurgical Quarterly》1998,25(5):322-330
1. The present study was performed to test whether beat-to-beat cardiovascular control in cardiac allograft recipients resides in cholinergic and/or adrenergic nerves that are intrinsic to the heart. 2. Heart rate (HR) fluctuations synchronous with respiration during spontaneous, double tidal volume and metronome-synchronized breathing were quantified in 13 human heart transplant recipients. We also examined the effects of sequential cholinergic and beta-adrenoceptor (combined) autonomic blockade on respiratory sinus arrhythmia (RSA). We computed RSA amplitude and the correlation between respiration and changes in HR (cardiopulmonary synchronization; CPS). Group means were compared using repeated-measures analysis of variance. Transplant recipients served as their own controls. 3. In the basal state, moderate RSA amplitude and CPS were observed. During cholinergic and combined blockade, we observed no significant change in RSA amplitude, whereas CPS increased significantly during combined blockade (P < 0.05). The amplitude of RSA increased during respiration at double baseline tidal volume, but not at any of the other breathing manoeuvres (P < 0.01). In contrast, CPS increased significantly during both patterned breathing manoeuvres. No significant correlation was seen between mean right atrial pressure and RSA amplitude. In 23% of subjects with low CPS, HR oscillated with arterial pressure. These oscillations were independent of respiration. During all three patterns of respiration, a significant inverse correlation was observed between CPS and pulse pressure (r = -0.53 to -0.73). Thus, as the amplitude of pulse pressure increased, respiration accounted for a smaller percentage of HR variation. 4. In conclusion, RSA persists and the magnitude of CPS increases following combined autonomic blockade. These studies suggest that while RSA after cardiac transplantation is not cholinergically or adrenergically mediated, it may be related to mechanical stretch of the sinus node caused by changes in intrathoracic pressure and perfusion pressure. 相似文献
998.
999.
1000.
JM Perkins TR Magee LJ Hands J Collin RB Galland PJ Morris 《Canadian Metallurgical Quarterly》1998,16(3):203-207
The authors report a case of paraplegia caused by a lumbar intraspinal paracoccidioidomycosis (PCM) granuloma. Clinical neurological diagnosis of a compressive spinal cord lesion was confirmed by spinal magnetic resonance imaging (MRI). Patient was submitted to surgery with total excision of the lesion. Histopathological analysis confirmed the diagnosis of PCM. Patient is on sulfamethoxazole/trimethoprim combined with fluconazole and is experiencing positive neurological recovery. 相似文献