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61.
Psychobehavioral treatment in cardiac rehabilitation   总被引:1,自引:0,他引:1  
This article reviews the empirical evidence for the use of behavioral and psychological therapies in the rehabilitation of patients with coronary disease. Exercise training, Type A modification, psychological counseling, smoking cessation, and dietary modification are considered. It is concluded that psychobehavioral therapies offer considerable promise to coronary patients in improving quality and quantity of life.  相似文献   
62.
Compression measurements were conducted on three explosive formulation binders, extruded Estane, plasticized Estane, and plasticized hydroxyl‐terminated polybutadiene, as a function of temperature and strain rate. The mechanical response of the Estane was found to exhibit the strongest dependency on strain rate and temperature and higher flow strength for similar test conditions of the three materials tested. Plasticized Estane was less sensitively dependent on strain rate and temperature, followed by the plasticized HTPB. The visco‐elastic recovery of all three binders is seen to dominate the mechanical behavior at temperatures above the glass transition temperature (Tg). There is a pronounced shift in the apparent Tg to higher temperatures as the strain rate is increased. Two distinct behaviors are observed in the binders below the Tg. At low strain rates, the binders exhibit a yield behavior, followed by a drop in the flow stress, which may or may not recover. At high strain rates, the load drop does not occur and the flow stresses either gradually increase, as in plasticized HTPB, or it levels out as seen in the Estane‐based binders. POLYM. ENG. SCI., 46:812–819, 2006. © 2006 Society of Plastics Engineers  相似文献   
63.
The Epstein-Barr virus is a ubiquitous human herpesvirus that is associated with an increasing number of human malignancies. Among these are Epstein-Barr virus-associated lymphoproliferative diseases in immunocompromised patients, a spectrum of mainly B-cell diseases that range from polyclonal lymphoproliferative diseases, which resolve when immunosuppression is halted, to highly malignant lymphomas. Progress has identified Epstein-Barr virus gene products involved in B-cell transformation, variation in Epstein-Barr virus transforming genes, distinct target cell populations with differing regulation of Epstein-Barr virus expression, and selective recruitment of other supportive cell types as factors in the heterogeneity of lymphoproliferative diseases. New therapeutic approaches to treat lymphoproliferative diseases are also being developed. Finally, xenotransplantation poses new risks for the introduction of Epstein-Barr virus-like viruses and more aggressive lymphoproliferative diseases in heavily immunosuppressed patients.  相似文献   
64.
Methodological recommendations common during the last 30 years have not prevented the emergence of views which are arguably no less caricatured and incorrect than was previously the case, even when account is taken of the heavily biased, mainly nationalistic, accounts concerning Lavoisier from the century after 1835. This article considers many of the categories of Lavoisier's achievement in chemistry, considers some of the more startling issues in the recent historiography, including negative accounts by Bensaude‐Vincent (1993), Siegfried (1988), Kim (2003) and Chang (2009, 2010, 2011, and 2012), and contributes towards a process of identifying a judicious view.  相似文献   
65.
Experimental studies have been conducted to examine the strength and fracture behaviour of monofilament Nicalon SiC fibres with diameters ranging from 8 to 22 m. The effects of varying fibre diameter, flaw location and flaw population on the mechanical response of individual fibres were investigated by recourse to extensive fractographic analysis performed on fibres fractured under tensile loading. Results indicate that variations in fibre diameter influence the apparent fibre fracture toughness (K1c), with higher K1c values observed for decreasing fibre diameters. Observations also suggest that the location of the critical flaw may play a role in the fracture of Nicalon fibres. Tensile strength values are shown to increase as the normalized distance of the critical flaw from the fibre centre increases, while critical flaw population appears to be strongly dependent on location. The ratio of K1c to geometry factor (Y) is observed to remain constant with varying flaw location. In addition to surface flaws, three distinct internal flaw populations are seen to cause fracture in Nicalon fibres. Based on these experimental findings, a statistical characterization of the strength of Nicalon fibres with varying diameters is presented in Part II of this paper. © 1998 Chapman & Hall  相似文献   
66.
Weakly textured hot-pressed (HP) beryllium and strongly textured hot-rolled beryllium were compressed using a split-Hopkinson pressure bar (SHPB) (strain rate ∼4500 s−1) to a maximum of 20 pct plastic strain as a function of temperature. The evolution of the crystallographic texture was monitored with neutron diffraction and compared to polycrystal plasticity models for the purpose of interpretation. The macroscopic response of the material and the active deformation mechanisms were found to be highly dependent on the orientation of the load with respect to the initial texture. Specifically, twinning is inactive when loaded parallel to the strong basal fiber but accounts for 27 pct of the plastic strain when loaded transverse to the basal fiber. In randomly textured samples, 15 pct of the plastic strain is accomplished by twinning. The role of deformation mechanisms with components out of the basal plane (i.e., twinning and pyramidal slip) is discussed.  相似文献   
67.
Using site-directed mutagenesis, we proposed that an autoinhibitory domain(s) is located at the C-terminal region (301-386) of the phosphorylase kinase gamma-subunit (Huang, C.-Y.F., Yuan C.-J., Livanova, N.B., and Graves, D.J. (1993) Mol. Cell. Biochem. 127/128, 7-18). Removal of the putative inhibitory domain(s) by truncation results in the generation of a constitutively active and calmodulin-independent form, gamma 1-300. To probe the structural basis of autoinhibition of gamma-subunit activity, two synthetic peptides, PhK13 (gamma 303-327) and PhK5 (gamma 343-367), corresponding to the two calmodulin-binding regions, were assayed for their ability to inhibit gamma 1-300. Competitive inhibition of gamma 1-300 by PhK13 was found versus phosphorylase b (Ki = 1.8 microM) and noncompetitive inhibition versus ATP. PhK5 showed noncompetitive inhibition with respect to both phosphorylase b and ATP. Calmodulin released the inhibition caused by both peptides. These results indicate that there are two distinct auto-inhibitory domains within the C terminus of the gamma-subunit and that these two domains overlap with the calmodulin-binding regions. Two mutant forms of gamma 1-300, E111K and E154R, were used to probe the enzyme-substrate-binding region using peptide substrate analogs corresponding to residues 9-18 of phosphorylase b (KRK11Q12ISVRGL). The data suggest that Glu111 interacts with the P-3 position of the substrate (Lys11) and Glu154 interacts with the P-2 site (Gln12). Both E111K and E154R were competitively inhibited with respect to phosphorylase b by PhK13, with 14- and 8-fold higher Ki values, respectively, than that observed with the wild-type enzyme. These data are consistent with a model for the regulation of the gamma-subunit of phosphorylase kinase in which PhK13 acts as a competitive pseudosubstrate that directly binds the substrate binding site of the gamma-subunit (Glu111 and Glu154).  相似文献   
68.
The effects of 16 wks of physical exercise training on the psychological functioning of 90 patients with mild hypertension were examined. At baseline and after 16 wks of training, patients completed a psychometric test battery that included objective measures of neuropsychological performance and standardized self-report measures of psychosocial functioning. Patients were randomly assigned to 1 of 3 groups: aerobic exercise, strength training and flexibility exercise, or a waiting list control group. After training, there were no group differences on any of the psychological measures, even though patients who engaged in exercise perceived themselves as functioning better in a number of psychological domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
69.
This study describes the affective component of hostility as measured by the Cook-Medley Hostility Scale (Ho W. Cook & D. Medley, 1954) by examining the relationship between facial expressions of emotion and Ho scores in 116 male coronary heart disease patients. Patients underwent the videotaped Type A Structured Interview, from which facial expressions were later coded using the Facial Action Coding System. They also completed the Cook-Medley Ho scale. Facial expression of the emotion of contempt was significantly related to Ho scores; anger expression was not. Also, there was a significant interaction between hostility and defensiveness, wherein low-defensive, highly hostile people showed substantially more contempt expression than others. The implications of these findings for the construct validity of Ho and for identifying clinically important subtypes of hostility are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
70.
The amino acid sequence of Cerebratulus toxin B-IV, a crustacean-selective axonal toxin occurring in the marine worm C. lacteus, was determined by Edman degradation of the tryptic and staphylococcal protease peptides obtained from the reduced, carboxymethylated toxin. All four of the anticipated maleylated tryptic peptides, ranging in size from 8 to 23 residues, and three staphylococcal protease peptides, ranging from 9 to 35 residues, were isolated in pure form by gel filtration followed by either ion exchange chromatography or preparative paper electrophoresis. The order of the maleylated tryptic peptides was based upon the sequences of the staphylococcal protease peptides. As might be expected, toxin B-IV displays no homology with the elapid nicotinic receptor toxins. In addition, toxin B-IV is structurally unrelated to a group of scorpion neurotoxins which, like B-IV, affect action potential generating mechanisms.  相似文献   
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