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51.
Carroll Douglas; Smith George Davey; Sheffield David; Shipley Martin J.; Marmot Michael G. 《Canadian Metallurgical Quarterly》1997,16(2):131
This study investigated the relationship among blood pressure reactions to mental stress, cynical hostility, and socioeconomic status (SES) in 1,091 male public servants. Occupational grade served to index SES and cynical hostility was assessed using the Cook-Medley scale. (Cook & Medley, 1954). The magnitude of systolic, but not diastolic, blood pressure change scores to stress was positively associated with occupational grade: the higher the grade, the greater the reactions. Mental stress task performance also varied with occupational grade but was unrelated to reactivity. Ratings of task difficulty did not vary with occupational grade. Cynical hostility was negatively related to occupational grade, and, contrary to previous findings, negatively related to systolic blood pressure reactivity. Cynical hostility was also negatively related to mental stress task performance but unrelated to ratings of task difficulty. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
53.
JC Macdonald FJ Torriani LS Morse MP Karavellas JB Reed WR Freeman 《Canadian Metallurgical Quarterly》1998,177(5):1182-1187
The suppression of human immunodeficiency virus (HIV) replication and elevation in CD4 cells observed with protease inhibitor combination regimens known as HAART (highly active antiretroviral therapy) may allow AIDS patients to undergo an immune recovery that allows them to suppress the progression of cytomegalovirus (CMV) retinitis. Eleven AIDS patients receiving HAART with healed CMV retinitis in whom CMV-specific maintenance therapy was discontinued were studied. Median CD4 cell counts were 42 before the initiation of HAART and 183 at discontinuation of anti-CMV therapy. While a median 1.1 log10 drop in plasma HIV-1 RNA was obtained between starting HAART and withdrawal of maintenance therapy for CMV, only 3 of 11 patients maintained plasma HIV RNA below the limits of detection. Reactivation of CMV retinitis after withdrawal of anti-CMV therapy did not occur in any of the patients observed for a median of 156 days (range, 92-558). 相似文献
54.
CK Damer J Partridge WR Pearson TA Haystead 《Canadian Metallurgical Quarterly》1998,273(38):24396-24405
Microcystin-affinity chromatography was used to purify 15 protein phosphatase 1 (PP1)-binding proteins from the myofibrillar fraction of rabbit skeletal muscle. To reduce the time and amount of material required to identify these proteins, proteome analysis by mixed peptide sequencing was developed. Proteins are resolved by SDS-polyacrylamide gel electrophoresis, electroblotted to polyvinylidene fluoride membrane, and stained. Bands are sliced from the membrane, cleaved briefly with CnBr, and applied without further purification to an automated Edman sequencer. The mixed peptide sequences generated are sorted and matched against the GenBank using two new programs, FASTF and TFASTF. This technology offers a simple alternative to mass spectrometry for the subpicomolar identification of proteins in polyacrylamide gels. Using this technology, all 15 proteins recovered in PP-1C affinity chromatography were sequenced. One of the proteins, PP-1bp55, was homologous to human myosin phosphatase, MYPT2. A second, PP-1bp80, identified in the EST data bases, contained a putative PP-1C binding site and a nucleotide binding motif. Further affinity purification over ATP-Sepharose isolated PP-1bp80 in a quaternary complex with PP-1C and two other proteins, PP-1bp29 and human p20. Recombinant PP-1bp80 also bound PP-1C and suppressed its activity toward a variety of substrates, suggesting that the protein is a novel regulatory subunit of PP-1. 相似文献
55.
SA Eisen R Neuman J Goldberg WR True J Rice JF Scherrer MJ Lyons 《Canadian Metallurgical Quarterly》1998,60(5):533-539
STATEMENT OF PROBLEM: Use of temporary crowns and fixed partial dentures is especially relevant when the treatment plan requires restorations for long interim periods, and the in-service discoloration of provisional restorative materials is a major drawback. PURPOSE: This study evaluated the discoloration effect of coffee and tea on some materials that are commonly used in the fabrication of provisional restorations. MATERIAL AND METHODS: Six commercially available provisional resins (Jet, Caulk TBR, Protemp Garant, Luxatemp Solar, Provipont DC and SR-Ivocron-PE) were evaluated after 1 day, 7 days, and 30 days of immersion in various staining solutions. Color measurements were obtained by using a Dr Lange Micro Color tristimulus colorimeter and color differences (delta E*) were estimated. RESULTS: The 2 chemically activated resins (Jet and Caulk TBR) and the heat-cured resin (SR-Ivocron PE) exhibited the least color changes, whereas the Provipont-DC resin was the least color stable. After immersion for 30 days, the combination with the coffee solution resulted in unacceptable discoloration for all the tested materials. CONCLUSIONS: Provisional restorative materials, staining solutions, and immersion time were significant factors that affected color stability. After immersion for 7 days, all materials showed observable color changes. The composite-based materials, especially light-curing composites, were the least color stable. The coffee solution exhibited more staining capacity than the tea solution. 相似文献
56.
TL Tekirian TC Saido WR Markesbery MJ Russell DR Wekstein E Patel JW Geddes 《Canadian Metallurgical Quarterly》1998,57(1):76-94
The goals of this study were twofold: to determine whether species differences in Abeta N-terminal heterogeneity explain the absence of neuritic plaques in the aged dog and aged bear in contrast to the human; and to compare Abeta N-terminal isoforms in parenchymal vs cerebrovascular Abeta (CVA) deposits in each of the species, and in individuals with Alzheimer disease (AD) vs nondemented individuals. N-terminal heterogeneity can affect the aggregation, toxicity, and stability of Abeta. The human, polar bear, and dog brain share an identical Abeta amino acid sequence. Tissues were immunostained using affinity-purified polyclonal antibodies specific for the L-aspartate residue of Abeta at position one (AbetaN1[D]), D-aspartate at N1 (AbetaN1[rD]), and pyroglutamate at N3 (AbetaN3[pE]) and p3, a peptide beginning with leucine at N17 (AbetaN17[L]). The results demonstrate that each Abeta N-terminal isoform can be present in diffuse plaques and CVA deposits in AD brain, nondemented human, and the examined aged animal models. Though each Abeta N-terminal isoform was present in diffuse plaques, the average amyloid burden of each isoform was highest in AD vs polar bear and dog (beagle) brain. Moreover, the ratio of AbetaN3(pE) (an isoform that is resistant to degradation by most aminopeptidases) vs AbetaN17(L)-x (the potentially nonamyloidogenic p3 fragment) was greatest in the human brain when compared with aged dog or polar bear. Neuritic plaques in AD brain typically immunostained with antibodies against AbetaN1(D) and AbetaN3(pE), but not AbetaN17(L) or AbetaN1(rD). Neuritic deposits in nondemented individuals with atherosclerotic and vascular hypertensive changes could be identified with AbetaN1(D), AbetaN3(pE), and AbetaN1(rD). The presence of AbetaN1(rD) in neuritic plaques in nondemented individuals with atherosclerosis or hypertension, but not in AD, suggests a different evolution of the plaques in the two conditions. AbetaN1(rD) was usually absent in human CVA, except in AD cases with atherosclerotic and vascular hypertensive changes. Together, the results demonstrate that diffuse plaques, neuritic plaques, and CVA deposits are each associated with distinct profiles of Abeta N-terminal isoforms. 相似文献
57.
WR Bishai NM Graham S Harrington DS Pope N Hooper J Astemborski L Sheely D Vlahov GE Glass RE Chaisson 《Canadian Metallurgical Quarterly》1998,280(19):1679-1684
Stevioside is a sweet-tasting glycoside, composed of stevia, a diterpenic carboxylic alcohol with three glucose molecules, mainly used as a substitute for non-alcoholic sweetener. It has previously been shown to reduce blood pressure in studies in animals and human. The effect of intravenous stevioside on the blood pressure was studied in spontaneously hypertensive rats (SHR). The hypotensive effect on both systolic and diastolic blood pressure was dose-dependent for intravenous doses of 50, 100 and 200 mg/kg in conscious SHR. The maximum reductions in systolic and diastolic blood pressure were 31.4 +/- 4.2% and 40.8 +/- 5.6% (mean +/- SEM) respectively and the hypotensive effect lasted for more than 60 min with a dose of 200 mg/kg. Serum dopamine, norepinephrine and epinephrine levels were not changed significantly 60 min after intravenous injection of stevioside 100 mg/kg in anesthetized SHR. The present data show that stevioside given intravenously to conscious SHR was effective in blood pressure reduction and there was no change in serum catecholamines in anaesthetized animals with this natural compound. 相似文献
58.
The anatomy of cranial nerves I and III through XII are presented. Each nerve is diagrammatically illustrated from its nuclear or its sensory origin and correlated with magnetic resonance and computed tomography images. The important identifying anatomical landmarks are demonstrated along the course of each nerve. Peripheral motor and sensory components are also discussed. 相似文献
59.
OBJECTIVE: To review the literature investigating the effects of parental affective illness on children over the past decade. METHOD: A computerized search of articles published over the past 10 years was completed. Articles were reviewed and relevant studies are presented. RESULTS: Over the course of the past 10 years a number of longitudinal studies have confirmed that children of affectively ill parents are at a greater risk for psychiatric disorders than children from homes with non-ill parents. Life table estimates indicate that by the age of 20 a child with an affectively ill parent has a 40% chance of experiencing an episode of major depression. Children from homes with affectively ill parents are more likely to exhibit general difficulties in functioning, increased guilt, and interpersonal difficulties as well as problems with attachment. Marital difficulties, parenting problems, and chronicity and severity of parental affective illness have been associated with the increased rates of disorder observed in these children. CONCLUSION: The presence of depression in parents should alert clinicians to the fact that their children also may be depressed and therefore in need of services. J. Am. Acad. Child Adolesc. 相似文献
60.
BACKGROUND: The homodimeric nitric oxide synthase (NOS) catalyzes conversion of L-arginine to L-citrulline and nitric oxide. Each subunit contains two flavins and one protoporphyrin IX heme. A key component of the reaction is the transfer of electrons from the flavins to the heme. The NOS gene encodes two domains linked by a short helix containing a calmodulin-recognition sequence. The reductase domain binds the flavin cofactors, while the oxygenase domain binds heme and L-arginine and additionally mediates the dimerization of the NOS subunits. We investigated the origin of the unusual magnetic properties (rapid-spin relaxation) of an air-stable free radical localized to a reductase domain flavin cofactor. RESULTS: We characterized the air-stable flavin in wild-type NOS, both in the presence and absence of calcium and calmodulin, the imidazole-bound heme complex of wild-type NOS, the NOS Cys415-->Ala mutant, and the isolated reductase domain. All preparations of NOS had the same flavin electron-spin relaxation behavior. No half-field transitions or temperature-dependent changes in the linewidth of the radical spin signal were detected. CONCLUSIONS: These data suggest that the observed relaxation enhancement of the NOS flavin radical is caused by the environment provided by the reductase domain. No magnetic interaction between the heme and flavin cofactors was detected, suggesting that the flavin and heme centers are probably separated by more than 15 A. 相似文献