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991.
OBJECTIVE: To examine (a) changes in subjects' self-care self-efficacy over time and (b) the relationship of subjects' self-care self-efficacy with adjustment to hemodialysis. DESIGN: A longitudinal design was used to study changes in self-care self-efficacy and associations between self-care self-efficacy and measures of adjustment: health status, mood distress, symptom distress, dialysis stress, and perceived adherence to fluid restriction. SAMPLE/SETTING: Subjects were recruited from 8 settings in the Northeast where outpatient hemodialysis treatment was administered. Sixty-four subjects were recruited to the study. Twenty-eight subjects completed 3 occasions of data collection. METHODS: Data were collected on three occasions: (a) baseline-within 100 days of beginning treatment; (b) 4 months after beginning treatment; and (c) 8 months after beginning treatment. Eta-squared, a measure of practical significance, is reported for four factors of the self-care self-efficacy measure on each of the three occasions. Associations between self-care self-efficacy and measures of adjustment were examined by means of Pearson correlations. RESULTS: Eta-squared estimates showed generally positive changes occurring over time in subjects' self-care self-efficacy, health status, mood distress, symptom distress, dialysis stress, and perceived adherence to fluid restriction. Changes were more positive at 4-months than at 8-months after enrollment. Significant correlations (p < .05) occurred between self-care self-efficacy and mood states, health status, symptom distress, and perceived adherence to fluid restrictions. Correlations occurred more frequently between self-care self-efficacy and mood states than between self-care self-efficacy and other measures of adjustment. CONCLUSIONS: The study provided pilot data suggesting that hemodialysis patients' self-care self-efficacy and measures of adjustment change over time. Patients who had increased confidence in self-care strategies (self-efficacy) were associated with having more positive mood states, health status, and perceived adherence to fluid restrictions and less symptom distress. Interventions designed to increase patients' self-care self-efficacy may yield positive results. Nurses are in an excellent position to give efficacy enhancing feedback that may promote patients' adjustment. 相似文献
992.
Helen Sharp Nathan Baddoo Sarah Beecham Tracy Hall Hugh Robinson 《Information and Software Technology》2009,51(1):219-233
Motivation in software engineering is recognized as a key success factor for software projects, but although there are many papers written about motivation in software engineering, the field lacks a comprehensive overview of the area. In particular, several models of motivation have been proposed, but they either rely heavily on one particular model (the job characteristics model), or are quite disparate and difficult to combine. Using the results from our previous systematic literature review (SLR), we constructed a new model of motivation in software engineering. We then compared this new model with existing models and refined it based on this comparison. This paper summarises the SLR results, presents the important existing models found in the literature and explains the development of our new model of motivation in software engineering. 相似文献
993.
SR Wood IR Sharp EO Caul I Paul AS Bailey M Hawkins S Pugh J Treharne S Stevenson 《Canadian Metallurgical Quarterly》1997,51(3):198-201
Four fluorescent antibody reagents were evaluated for their suitability for the identification of adenovirus isolates by immunofluorescence. The antibodies used in the reagents consist of monoclonal antibodies against adenovirus type 3 (Ad3), Ad4, Ad8, and adenoviruses of subgroup C (Ad1,2,5,6), serotypes known to occur in outbreaks of disease. Most of the monoclonal antibodies employed were reactive against type-specific antigens found on the hexon protein. Reagents employing two noncompeting anti-hexon antibodies were more sensitive than reagents prepared with only one monoclonal antibody, although both types of reagents exhibited a high degree of specificity. Five hundred and seventeen adenovirus isolates (359 of which had previously been typed by other methods) and 46 nonadenovirus isolates were examined with all four type-specific reagents in parallel with an adenovirus group-specific reagent. The results indicate that direct typing of adenovirus isolates is feasible, leading to significant savings in time compared to other typing methods and should contribute to the management of certain adenovirus infections, particularly during outbreaks. 相似文献
994.
Insulin-like growth factor I (IGF-I) is a potent neurotropic factor promoting the differentiation and survival of neuronal cells. SH-SY5Y human neuroblastoma cells are a well characterized in vitro model of nervous system growth. We report here that IGF-I stimulated the tyrosine phosphorylation of the type I IGF receptor (IGF-IR) and insulin receptor substrate-2 (IRS-2) in a time- and concentration-dependent manner. These cells lacked IRS-1. After being tyrosine phosphorylated, IRS-2 associated transiently with downstream signaling molecules, including phosphatidylinositol 3-kinase (PI 3-K) and Grb2. Treatment of the cells with PI 3-K inhibitors (wortmannin and LY294002) increased IGF-I-induced tyrosine phosphorylation of IRS-2. We also observed a concomitant increase in the mobility of IRS-2, suggesting that PI 3-K mediates or is required for IRS-2 serine/threonine phosphorylation, and that this phosphorylation inhibits IRS-2 tyrosine phosphorylation. Treatment with PI 3-K inhibitors induced an increased association of IRS-2 with Grb2, probably as a result of the increased IRS-2 tyrosine phosphorylation. However, even though the PI 3-K inhibitors enhanced the association of Grb2 with IRS-2, these compounds suppressed IGF-I-induced mitogen-activated protein kinase activation and neurite outgrowth. Together, these results indicate that although PI 3-K participates in a negative regulation of IRS-2 tyrosine phosphorylation, its activity is required for IGF-IR-mediated mitogen-activated protein kinase activation and neurite outgrowth. 相似文献
995.
I Khreisat A Simonetta EL Attinà G Monasterolo GF Bertone T Beccaria RE Rossi 《Canadian Metallurgical Quarterly》1997,17(1):22-25
An 8-year-old Italian boy, born to consanguineous parents, with clinical, histopathologic, and ultrastructural findings of lipoid proteinosis is reported. The main signs of the syndrome-papulonodular, hyperkeratotic and verrucous lesions distributed over the skin of the head and extremities, hoarseness, and dysphagia-were present in the child. The mother had papulonodular lesions on her hands and also complained of slowness in healing. 相似文献
996.
997.
S. S. ABD EL REHIM N. F. MOHAMED N. H. AMIN L. I. ALI 《Journal of Applied Electrochemistry》1997,27(12):1385-1389
Pb–Cu alloy coatings were electrodeposited on steel sheet cathodes from baths containing mixtures of lead nitrate, copper nitrate and sodium gluconate. Cathodic polarization, cathodic current efficiency and deposit composition were determined under different plating conditions. The results were consistent with the behaviour of a regular plating system with copper being the preferentially depositable metal. The lead (the less noble metal) content in the deposits increased with increase in current density and concentration of lead in the bath but decreased with increase in bath copper concentration. The structure and morphology of the as-deposited coatings were examined by X-ray, AES and SEM. The results showed that the deposits consist of a mixture of fine crystals of the two metals and the morphology of the deposits is mainly controlled by the composition of the deposit. 相似文献
998.
BACKGROUND AND OBJECTIVES: Risk-taking behaviors differ among women and men injection drug users (IDU). GOAL: To specify the nature of sexual and drug risk-taking among women IDU and ex-IDU and how it relates to partner characteristics. DESIGN: A cross-sectional analysis of 324 HIV+ subjects enrolled into a prospective cohort study in Marseille, France. RESULTS: Women, as compared with men, were considerably more likely to report nonuse of condoms with a main partner (31% versus 12%). They were more likely to shoot with a partner at last injection (39% versus 12%), but far less likely to sterilize used needles (4% versus 16%). Two thirds of both men and women reported consistent condom use with a seronegative partner, but only 47% of men and 23% of women reported the same with a seropositive partner. Among the women only, needle and syringe sharing was associated with consistent use of a condom. CONCLUSIONS: Women reported behaviors which protect their partners from STD infection more frequently than behaviors which protect themselves. Greater attention must be paid to sexual risk-taking among HIV+ women. 相似文献
999.
Powerful mutagenic screens of yeast Saccharomyces cerevisiae have recently been developed which require strains that lack the endogenous 2 micron plasmid (Burns et al., 1994). Here, we describe a simple and reliable method for curing yeast of the highly stable genetic element. The approach employs heterologous expression of a 'step-arrest' mutant of the Flp recombinase. The mutant, Flp H305L (Parsons et al., 1988), forms long-lived covalent protein-DNA complexes exclusively at 2 micron-borne recombinase target sites. In vivo, the complexes serve as sites of targeted DNA damage. Using Southern hybridization and a colony color assay for plasmid loss, we show that expression of the mutant enzyme results in the effective elimination of the 2 micron from cells. 相似文献
1000.
We recorded head direction (HD) cells from the lateral mammillary nucleus (LMN) and anterior thalamus (ATN) of freely behaving rats and also made bilateral lesions of LMN while recording HD cells from ATN. We discovered that the tuning functions of LMN HD cells become narrower during contraversive head turns, but not ipsiversive head turns, compared to when the head is not turning. This narrowing effect does not occur for ATN HD cells. We also found that the HD signal in LMN leads that in ATN by about 15-20 ms. When LMN was lesioned bilaterally, HD cells in ATN immediately lost their directional firing properties and never recovered them. Based on these findings, we argue that LMN may be an essential component of an attractor-integrator network that participates in generating the HD signal. 相似文献