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91.
92.
Denise Haderski Sergey Nazarenko Chih-Min Cheng Anne Hiltner Eric Baer 《Macromolecular chemistry and physics.》1995,196(8):2545-2561
The crystallization behavior of coextruded microlayered sheets comprised of 657 alternating layers of polycarbonate (PC) and a miscible copolyester of mainly 1,4-cyclohexanedimethanol and terephthalic acid (KODAR) was investigated as a function of annealing time when the KODAR was crystallized isothermally from the glass at 195°C. Comparisons were made with crystallization of KODAR alone, and with crystallization of KODAR from melt blends with PC. The kinetics of crystallization and the morphology of the crystallized KODAR were characterized with differential scanning calorimetry, and by examination of thin sections microtomed from annealed specimens in the polarized light microscope and the transmission electron microscope. The growth rate of small, birefringent KODAR spherulites was non-linear, and was strongly affected by diffusion of PC into the KODAR layers. Diffusion of amorphous PC into the KODAR layers retarded nucleation and spherulite growth and decreased spherulite density. The effect became more pronounced as the KODAR layer thickness was reduced. Spherulities nucleated randomly throughout the KODAR layers in the PC/KODAR 20/80 (w/w) microlayer and grew rapidly to form a continuous layer of impinged spherulites. In contrast, spherulites in the PC/KODAR 40/60 and 60/40 microlayers nucleated and grew along the center of the KODAR layers where the KODAR concentration was highest. 相似文献
93.
94.
SARAH VOOGHT BSc RGN ALISON RICHARDSON PhD MSc RGN 《European journal of cancer care》1996,5(4):217-224
Cancer patients are increasingly being cared for in the community. However, the role of the community oncology nurse specialist (CONS) remains a rare appointment in the United Kingdom. There is little research evidence to substantiate the view that this is a worthwhile and effective role. This study aimed to explore the role of one CONS using a qualitative case study approach. The sample consisted of the CONS, seven patients, no relatives and five community nurses. Semi-structured interviews were used to elicit the view of these participants. In addition, documents containing details of the CONS's work to date were reviewed. A number of the CONS's role components were identified by the different respondent groups. Five themes were identified within the data collected: functions of the CONS, communication between the CONS and other health care professionals, structural and organizational factors, characteristics of the service and benefits to patients and their families. Furthermore, all respondent groups were positive about the service offered by the CONS, and felt that the role was valuable. Some negative features were identified and these were concerned with organizational aspects of the service. The findings suggest the need for further research and evaluation in this area. 相似文献
95.
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97.
Hartley Dean MA PhD Keir Gale BA Roger Woods BA MA 《Health & social care in the community》1996,4(6):338-346
The new complaints procedures which local authority social services departments have been required to introduce represent an important mechanism for managing the change of culture associated with recent community care reforms. They also represent a new genre in mechanisms of redress for welfare recipients. This paper reports the findings of a study which has observed considerable diversity in the ways in which local authorities are interpreting the nature and purposes of the new procedures and, in particular, the functions of review panels established under those procedures. Variations in the composition of panels, in the style of review panel proceedings, in perceptions of the panels' powers, and in the ways that complaints and complainants are constituted are all discussed. Attention is drawn to four competing interpretations of the review panels' role and to the need for these to be clarified and prioritised. 相似文献
98.
Dr. Andrew G. Bostom M.D. Dr. Anne L. Hume Pharm.D. Dr. Charles B. Eaton M.D. Dr. Joseph P. Laurino Ph.D. Ms. Lisa R. Yanek B.A. Ms. Mary S. Regan B.S. Mr. William H. McQuade M.P.H. Dr. Wendy Y. Craig Ph.D. Ms. Gayle Perrone M.B.A. Dr. Paul F. Jacques Sc.D. 《Pharmacotherapy》1995,15(4):458-464
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD. 相似文献
99.
目的了解血管紧张素Ⅱ受体拮抗剂(ATRA)和转换酶抑制剂(ACEI)对慢性肾衰(CRF)高血压患者血浆心钠素(ANF)和肾素*.血管紧张素系统(RAS)的影响。方法受试者口服氯沙坦(Los组)或福辛普利(Fos组)连续12周,于治疗前和治疗后第4、8及12周测定坐位舒张压(SiDBP)、血清尿素氮(BUN)、血清肌酐(SCr)、ANF、血管紧张素Ⅰ(AⅠ)和血管紧张素Ⅱ(AⅡ)。用SPSS7.0软件作统计分析。结果经12周治疗,两组患者SiDBP均降至目标值。Fos组与治疗前比较,AⅡ下降,ANF和Scr升高(P<0.01)。Los组AⅡ明显升高(P<0.01),ANF在短暂升高后降至治疗前水平,Scr无变化。结论ACEI可能对CRF高血压患者肾内灌注压有影响,ANF动态改变可作为肾内灌注压变化的指标之一。ATRA对肾内灌注压影响小于ACEI。 相似文献
100.
Neil Scott Gordon MSc Dip Coun Dip N Cert Ed RCNT RNT RMN Peter Wimpenny RGN BSc Cert Ed RNT 《Journal of advanced nursing》1996,23(3):479-486
This paper, written by two male nurse teachers, describes and analyses their experience of working in a nurse education culture permeated by the philosophy of business management The introduction of business management practices to nurse education is discussed as a reflection of the current political hegemony of market forces and individualism The authors discuss the implications for nurse teachers of being continually exposed to these politically motivated forces which increasingly provide the paradigm for service developments within the United Kingdom health services In discussing the impact of this exposure it is argued that at the personal level individual teachers are experiencing a degree of apathy and personal dissonance which undermines their professional value system, resulting in emotional distress and a crisis of identity It provides a critical reflection on the way organizational dynamics and power relations influence the subjective sense-making of individuals The authors use a multiplicity of perspectives, including those provided by individual psychology, power relations, feminism and personhood, to argue for the need to develop an alternative paradigm which is characterized by the valuing of individual persons, empathic sensitivity and the fostering of creativity been important to us from a personal and professional 相似文献