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81.
This intervention study evaluates a decision-making aid for parents considering childhood immunizations. Participants (women in 3rd trimester of pregnancy, n = 100) rated likelihood of immunizing their child, anxiety, and perceptions of risk of the diseases and immunizations. Individuals were allocated to intervention group (received a decision aid) or control group (received standard care). Ratings were then repeated, and further ratings were obtained when the infant was 10 weeks old. The intervention compared with the comparison condition was associated with significant increase in likelihood of immunizing the infant on time, decreased perceptions of risks of immunizations, increased perceptions of risk of the diseases, reduced anxiety, and increased satisfaction. This intervention may form a useful basis for decision aids in health care settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
82.
Presents an obituary for Elizabeth Douvan (1926-2002). Douvan was a pioneer in the study of changing gender, work, and family roles; personal values; and well-being in the second half of the 20th century. Through her research, she contributed to the interdisciplinary fields of social psychology and women's studies while building and strengthening institutions that remain committed to the same mission. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
83.
Different forms of generativity in the writings of E. H. Erikson (1950/1963) and J. Kotre (1984) were related to agentic and communal motives in a sample of young adults (M?=?28 yrs old). For women, the power motive related to parenting, whereas the achievement motive was associated with forms of generative expression outside of the household. The opposite pattern of achievement and power motive relationships was found for men, although in a weaker form. The affiliation–intimacy motive, on the other hand, related both to women's parenting and societal concerns. Differences in expectations and opportunities for young men and women may account for these gender differences. The results for women support D. P. McAdams's (1988) suggestions that agency and communion are important for understanding generativity. In addition, the results provide evidence that people begin to grapple with generative issues as young adults. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
The effect of heat on double-strand breaks (dsb) repair was compared with thermal radiosensitization using HeLa S3 cells. Cells were exposed to a combined treatment of X-irradiation followed by heat (44 degrees C, 0.5 h) separated by time intervals up to 8 h. DNA dsb were measured by PFGE and survival by the colony forming assay. In non-heated HeLa S3 cells repair of dsb was biphasic with the majority of breaks being repaired fast with a half-time of 14 min and only a minority were repaired slowly with a half-time of 130 min. Heat applied immediately after irradiation was found to cause an increase in both half-times but mainly to result in an increased fraction of slowly repairable dsb. The latter effect was shown to result from the formation of additional dsb. The number of additional dsb declined when irradiation and heat were separated by an interval at 37 degrees C with a half-time of 120 +/- 30 min. This half-time was similar to the half-time of 100 +/- 20 min found for the loss of thermal radiosensitization studied for the same protocol. Both processes were recently found also to correlate in CHO cells but occurred much faster in rodent cells than in the human HeLa S3 cells used in the current study. These results show that in human cells, unlike previously suggested on the basis of rodent cells, thermal radiosensitization is still a substantial contributor to the killing efficacy of a combined treatment even when irradiation and heat are separated by a time internal of 4 h.  相似文献   
85.
College alumnae who had graduated 2, 12, or 22 years earlier completed questionnaires in which they recounted the first four memories to come to mind of their freshman year and provided ratings of each remembered experience. For all three alumnae groups, the temporal distribution of memories peaked in September, the beginning of college. Mean ratings of emotional intensity were high, mean ratings of surprise and life impact were below the moderate level and substantial numbers of memories had never been recounted previously. The proportion of memories that focused on specific episodes rather than on general experiences decreased as the number of years since graduation increased. The incidence of specific memories also declined as a function of memory order: Memories reported first were more likely to be specific than memories reported later. The results suggest that transitional and emotional episodes are especially likely to persist in memory for many years. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
86.
In patients suffering dilated cardiomyopathy, chagasic or not, and in healthy volunteers we applied signal-averaged electrocardiography to detect late potentials and to study heart autonomic control. Thus, with non-invasive methods, we were able to explore the progress of depolarization and heart rate variability. It was found that Chagasic patients have more late potentials and abnormalities in the heart variability; with less co-morbid process when compared with patients suffering miscellaneous cardiomyopathies. These preliminary findings corroborate and expand previous observations by several authors. The signal-averaged electrocardiogram is a valuable tool for clinical diagnosis and research, particularly for studies on dilated cardiomyopathy, specially those with parasitic etiology.  相似文献   
87.
The systems prepared in situ by addition of the corresponding equivalents of the respective phosphine (mono-, di- and tri-dentated), called M2Cl2(COE)4/n phosphine (M = Rh, Ir; and COE = cyclooctene), are efficient and regioselective precatalysts for the hydrogenation of quinoline, isoquinoline, 5,6- and 7,8-benzoquinoline and acridine. The Rh systems were more active than the corresponding Ir ones, being the systems with 1,1,1-tris(diphenylphosphinomethyl)ethane (triphos) more active than those with 1,2-bis(diphenylphosphino)ethane (dppe), except for the case of acridine, where the inversed tendencies were observed (Ir > Rh and dppe > triphos). The systems with triphenylphosphine showed the lowest activities.  相似文献   
88.
Abstract

A technique was developed for preparing a novel material that consists of gold nanoparticles trapped within a fiber of unfolded proteins. These fibers are made in an aqueous solution that contains HAuCl4 and the protein, bovine serum albumin (BSA). By changing the ratio of gold to BSA in solution, two different types of outcomes are observed. At lower gold to BSA ratios (30–120), a purple solution results after heating the mixture at 80 °C for 4 h. At higher gold to BSA ratios (130–170), a clear solution containing purple fibers results after heating the mixture at 80 °C for 4 h. UV–Vis spectroscopy and light scattering techniques show growth in nanocolloid size as gold to BSA ratio rises above 100. Data indicate that, for the higher gold to BSA ratios, the gold is sequestered within the solid material. The material mass, visible by eye, appears to be an aggregation of smaller individual fibers. Scanning electron microscopy and transmission electron microscopy indicate that these fibers are primarily one-dimensional aggregates, which can display some branching, and can be as narrow as 400 nm in size. The likely mechanism for the synthesis of the novel material is discussed.  相似文献   
89.
In this study, composites of unsaturated polyester resin (UPR), synthesized from recycled polyethylene terephthalate (PET), with 10 to 40% in volume of corn straw fiber (CSF), were elaborated and studied the effect of fiber content on their physical and mechanical properties. The content of cellulose (48.97%), hemicellulose (24.06%), and lignin (6.59%) were determined by chemical characterization of CSF. The characteristic bonds of the UPR were identified as a cross-linking network between the styrene monomer (ST) and the unsaturated polyester (UP) through FTIR. Two decomposition stages were observed by TGA–DTG. The results of physical and mechanical properties showed that as the fiber content increased in the UPR, the water absorption increased (0.6% to 2.56%), on the other hand, the density (1218.23 to 1150.28 kg/m3), flexural strength (50.58 to 26.98 MPa), flexural modulus (2.66 to 2.29 GPa), tensile strength (8.62 to 3.65 MPa), tensile modulus (1.18 to 0.43 GPa), and hardness (81.67 to 65.67 Shore D), they decreased. SEM analysis showed some defects in the fiber distribution in the UPR, which affected the mechanical properties of the composites. This research contributes to the development of new material from use of two waste materials for the benefit of the environment.  相似文献   
90.
Enzymes from secondary metabolic pathways possess broad potential for the selective synthesis of complex bioactive molecules. However, the practical application of these enzymes for organic synthesis is dependent on the development of efficient, economical, operationally simple, and well-characterized systems for preparative scale reactions. We sought to bridge this knowledge gap for the selective biocatalytic synthesis of β-hydroxy-α-amino acids, which are important synthetic building blocks. To achieve this goal, we demonstrated the ability of ObiH, an l -threonine transaldolase, to achieve selective milligram-scale synthesis of a diverse array of non-standard amino acids (nsAAs) using a scalable whole cell platform. We show how the initial selectivity of the catalyst is high and how the diastereomeric ratio of products decreases at high conversion due to product re-entry into the catalytic cycle. ObiH-catalyzed reactions with a variety of aromatic, aliphatic and heterocyclic aldehydes selectively generated a panel of β-hydroxy-α-amino acids possessing broad functional-group diversity. Furthermore, we demonstrated that ObiH-generated β-hydroxy-α-amino acids could be modified through additional transformations to access important motifs, such as β-chloro-α-amino acids and substituted α-keto acids.  相似文献   
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