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排序方式: 共有1307条查询结果,搜索用时 15 毫秒
141.
John W.M. Agar Christine A. Somerville Karen M. Dwyer Rosemary E. Simmonds Janeane M. Boddington Claire M. Waldron 《Hemodialysis international. International Symposium on Home Hemodialysis》2003,7(4):278-289
Background: Because home hemodialysis has long been a common Australian support modality, the advent of home‐based nocturnal hemodialysis (NHD) in Canada stimulated the extension of our existing home‐ and satellite‐based conventional hemodialysis (CHD) programs to NHD. As a result, the first government‐funded, home‐based, 6‐nights‐per‐week NHD program in Australia began in July 2001. Methods: Sixteen patients have been trained for NHD; 13 dialyzed at home 8 to 9 hr per night for 6 nights per week, whereas 3 preferred to train for NHD at home using an 8‐ to 9‐hr alternate‐night regime. Results: The program experience to March 1, 2003, was 655 patient‐weeks. Two patients had withdrawn for transplantation and 2 for social reasons, although 1 continues on alternate‐night NHD. There hade been no deaths. Ten patients had dialyzed without partners. All patients ceased phosphate binders at entry. Thirteen of 16 discontinued all antihypertensive drugs. There were no fluid or dietary restrictions. Phosphate was added to the dialysate to prevent hypophosphatemia. Pre‐ and postdialysis urea and phosphate levels were broadly within the normal ranges. All patients reported restorative sleep; similarly partners reported stable sleep patterns and noted improved mood, cognitive function, and marital relationships in their NHD partners. Preliminary cost analyses show that whereas consumables had doubled, and epoetin and iron expenditures had risen by 28.9%, other pharmaceutical costs had fallen by 47%, and nursing wage costs were 48% of the notional cost had these patients remained on CHD. Three patients on NHD were retired, 7 worked full‐time, 3 worked part‐time, and 3 drew disability support, whereas previously on CHD, 3 were retired, 3 had worked full‐time, 3 had worked part‐time, and 7 had drawn disability support. Conclusion: We believe that NHD is viable, safe, effective, and well accepted with significant lifestyle benefits and reemployment outcomes. Although initial setup costs are significant, NHD cost advantage over CHD progressively accrues as program numbers exceed 12 to 15 patients. 相似文献
142.
Claire Herpol 《火与材料》1976,1(1):29-35
This paper present observations on the toxicity of gases produced by materials under three different combustion conditions. The difficulty of the general problem of toxicity is emphasized and the impossibility—at the present stage in the research—of satisfying the increasing pressure to establish toxicity safety regulations is stated. 相似文献
143.
Antecedents of self-regulation: A developmental perspective. 总被引:2,自引:0,他引:2
The emerging ability to comply with caregivers' dictates and to monitor one's own behavior accordingly signifies a major growth of early childhood. However, scant attention has been paid to the developmental course of self-initiated regulation of behavior. The literature devoted to early forms of control is summarized, highlighting the different philosophical orientations. Focusing on the period from early infancy to the beginning of the preschool years, an ontogenetic perspective is proposed that traces the kinds of modulation or control of which the child is capable. The developmental sequence of monitoring behaviors that is proposed calls attention to contributions made by the growth of cognitive skills. The role of mediators (e.g., caregivers) is also discussed. (3 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
144.
Transmission electron microscopy has been used to identify the products in cellularly transformed regions of alloys based
on the Nimonic 80 A composition. The commercial alloy is shown to undergo a small degree of cellular transformation even after
conventional heat treatments, while recrystallization is found to increase the incidence of this reaction type. Low carbon
versions of this alloy demonstrate cellular precipitation over a wider range of heat treatments.
It is shown that the cellular reaction may take place in these alloys under a variety of different conditions and with a range
of driving forces. Reasons for this unexpected behaviour are offered, as is a suggestion as to why the cellular reaction occurs
on a local scale. 相似文献
145.
McGuire William J.; McGuire Claire V.; Child Pamela; Fujioka Terry 《Canadian Metallurgical Quarterly》1978,36(5):511
How likely people are to think of themselves in terms of a given personal characteristic is predicted from the distinctiveness postulate that the person, when confronted by a complex stimulus (such as the self), selectively notices and encodes the stimulus in terms of what is most peculiar about it, since these peculiar characteristics are the most informative in distinguishing it from other stimuli. This partial view of the person as an information-encoding machine (one is conscious of oneself insofar as, and in the ways that, one is different) is used to derive 4 predictions implying that ethnic identity is salient in children's spontaneous self-concepts to the extent that their ethnic group is in the minority in their social milieu at school. In testing 560 1st-, 3rd-, 7th-, and 11th-grade school children, the measure of salience of ethnicity was its being spontaneously mentioned by the children in response to a nondirective "Tell us about yourself" question. All 4 predictions were confirmed, though for several of the findings there are plausible alternative explanations. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
146.
The articles in this section point to directions for action regarding children's health and their emotional and developmental well-being. More than this, the authors describe the kinds of problems children face and why they arise. Equally important, all acknowledge the progress already made. The 11 articles in this section are grouped into two major categories: the first pertains to risks to children's mental health and behavior, and the second deals with risk factors and risk-taking behaviors. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
147.
148.
To unify numerical techniques in scientific calculations and control processes, a systematic numerical-data word-oriented method is proposed. The number of separate arithmetic instructions required is drastically reduced. Wired simple-precision floating-point operators can be used alternatively as autonomous operators or as basic cells for multiple-precision operators. 相似文献
149.
Duarte IF Stanley EG Holmes E Lindon JC Gil AM Tang H Ferdinand R McKee CG Nicholson JK Vilca-Melendez H Heaton N Murphy GM 《Analytical chemistry》2005,77(17):5570-5578
This work presents the first application of high-resolution magic angle spinning (HR-MAS) 1H NMR spectroscopy to human liver biopsy samples, allowing a determination of their metabolic profiles before removal from donors, during cold perfusion, and after implantation into recipients. The assignment of peaks observed in the 1H HR-MAS NMR spectra was aided by the use of two-dimensional J-resolved, TOCSY and 1H-13C HMQC spectra. The spectra were dominated by resonances from triglycerides, phospholipids, and glycogen and from a variety of small molecules including glycerophosphocholine (GPC), glucose, lactate, creatine, acetate, amino acids, and nucleoside-related compounds such as uridine and adenosine. In agreement with histological data obtained on the same biopsies, two of the six livers were found to contain high amounts of triglycerides by NMR spectroscopy, which also indicated that these tissues contained a higher degree of unsaturated lipids and a lower proportion of phospholipids and low molecular weight compounds. Additionally, proton T2 relaxation times indicated two populations of lipids, a higher mobility triglyceride fraction and a lower mobility phospholipid fraction, the proportions of which changed according to the degree of fat content. GPC was found to decrease from the pretransplant to the posttransplant biopsy of all livers except for one with a histologically confirmed high lipid content, and this might represent a biomarker of liver function posttransplantation. NMR signals produced by the liver preservation solution were clearly detected in the cold perfusion stage biopsies of all livers but remained in the posttransplant spectra of only the two livers with a high lipid content and were prominent mainly in the graft that later developed primary graft dysfunction. This study has shown biochemical differences between livers used for transplants that can be related to the degree and type of lipid composition. This technology might therefore provide a novel screening approach for donor organ quality and a means to assess function in the recipient after transplantation. 相似文献
150.
Stephenson C McCarthy J Vikelis E Shave R Whyte G Gaze D George K 《Ergonomics》2005,48(11-14):1585-1593
The purpose of this study was to assess left ventricular (LV) function and biochemical markers of myocyte after prolonged weightlifting activity. Seventeen male subjects (age range 20-34 years) performed a 90-min bout of weightlifting exercise consisting of three sets of 8-10 repetitions at 70% one-repetition maximum. Body mass, heart rate, systolic blood pressure (SBP) and echocardiographically determined indices of LV loading (LV internal diameter during diastole, LV meridonial wall stress), systolic function (stroke volume (SV), ejection fraction (EF), end-systolic pressure volume relationship; SBP/ESV) and diastolic filling (ratio of early to late; E:A) were obtained pre-exercise, immediately after and 24 h post-exercise. A 5-ml venous blood sample was obtained for the assessment of cardiac troponin T (cTnT) via third generation electrochemiluminescence assay. Data were assessed via one-way ANOVA and Pearson's correlation. Although SV declined (80.9 +/- 18.3 vs. 66.9 +/- 17.2, p < 0.05) there was no alteration in LV contractility (EF 62 +/- 6 vs. 59 +/- 7; SBP/ESV 3.51 +/- 1.4 vs. 3.51 +/- 1.4, p > 0.05). The E:A ratio was significantly decreased following exercise (1.78 +/- 0.41 vs. 1.33 +/- 0.37, p < 0.05). This decrease was not fully explained by loading conditions (r2 = 0.05 to 0.24). All values returned to baseline 24 h post-exercise. No cTnT was reported in any of the blood samples. In conclusion, there was no significant evidence of any LV contractile depression and no cTnT was observed post exercise. The small reduction in diastolic filling could not be explained by changes in haemodynamic loading or the post-exercise elevation in heart rate. 相似文献