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71.
72.
It is commonly believed that diet composition is important throughout life for optimizing bone health and reducing osteoporotic fracture risk. This contribution offers a critical overview of the main dietary components which are reported to be important. There is evidence to suggest that peak bone mass and later fracture risk are influenced by nutritional exposures in utero, in infancy and during childhood and adolescence. There are also particular concerns that individuals with a low calcium intake or vitamin D status may be at an increased risk, particularly at vulnerable periods during growth, and at times of high requirement (e.g. during pregnancy and lactation). Several other nutrients may play a key role in bone health, including vitamin K, phosphorus, potassium, magnesium, protein and sodium. In addition to specific nutrients, food groups (e.g. fruit and vegetables, pulses) may also have a positive effect on bone health. 相似文献
73.
The theory/practice 'gap': taking issue with the issue 总被引:3,自引:0,他引:3
Anne Marie Rafferty BSc MPhil DPhil RGN DN Nick Allcock BSc DipNEd RGN RNT Judith Lathlean BSc MA DPhil 《Journal of advanced nursing》1996,23(4):685-691
Theory/practice issues have a long-standing history in nurse education, and are a chronic source of controversy to which there is no easy or perfect solution We have argued that it is the tension between theory and practice and research which can be usefully exploited in teaching and research Students need to be introduced to the debates surrounding the genesis and generation of nursing knowledge They need to gain an appreciation of what counts as nursing knowledge at different points in time and the politics which drive the legitimation of nursing theory and practice Such an approach has much to offer in helping students deal with reality shock and make sense of their experience as they confront the ambiguities, uncertainties and contradictions that characterize the stock-in-trade of professional life 相似文献
74.
Roland D. Thijs MD David G. Benditt MD FACC FRCP Christopher J. Mathias MD DPhil DSc FRCP FMedSci Ronald Schondorf MD PhD Richard Sutton DScMed FRCP FESC FACC Wouter Wieling MD PhD J. Gert van Dijk MD PhD 《Clinical autonomic research》2005,15(1):35-39
Abstract
Background
Imprecise definitions of syncope and related conditions appear common in the medical literature. To investigate the scope of the problem we systematically searched for definitions in high-ranking medical journals.
Methods
Literature review of articles on syncope, neurocardiogenic syncope, neurally mediated syncope, orthostatic intolerance, and orthostatic hypotension with these keywords in the title, mainly published in the ten journals with the highest impact in the fields of cardiology, internal medicine, and neurology.
Results
Syncope, neurocardiogenic syncope, neurally mediated syncope, orthostatic intolerance, and orthostatic hypotension were defined in only 41%, 34%, 26%, 38%, and 48% of papers respectively. Definitions, when given, differed considerably among papers. Orthostatic hypotension was most frequently defined, with an increase in number and consistency of definitions after publication of a consensus in 1996.
Conclusions
Syncope and related conditions proved to be infrequently and inconsistently defined in current medical literature. The lack of consistent terminology is likely to harm medical education, research, and patient care. There is a strong need for a systematic terminology for syncope and related conditions. 相似文献
75.
Benedict CR 《Current hypertension reports》1999,1(4):305-312
Central regulation of the sympathetic nervous system plays an important role in the maintenance of blood pressure. In a subset
of patients with essential hypertension, sympathetic activation may contribute to the development and maintenance of hypertension.
Unlike the first generation of centrally active antihypertensive drugs, the second generation may be superior because of its
selectivity to I1-imidazoline receptor and selective binding to the vasomotor center. Lack of a2 effects differentiates moxonidine
from clonidine with respect to monoxidine’s superior side-effect profile (little or no sedation or dry mouth). Clinical trials
show that moxonidine is as effective as angiotensin-converting enzyme inhibitors (eg, enalapril and captopril), b-blockers
(eg, atenolol), calcium-channel blockers (eg, long-acting nifedipine), and diuretics (eg, hydrochlorothiazide) in lowering
blood pressure and that it has superior tolerability. Thus, central modulation of the sympathetic nervous system has re-emerged
as an exciting target for blood pressure reduction. Given the multiple adverse effects of sympathetic stimulation in various
disease processes, including congestive heart failure, moxonidine may be the next therapeutic option for the management of
hypertension and the prevention of target organ dysfunction. 相似文献
76.
77.
HUGH McKENNA CBE FRCN RGN RMN DipN BSc Adv Dip Ed RNT DPhil FRCSI SINEAD KEENEY BA MRes PhD FELICITY HASSON BA MSc Pg Dip 《Journal of nursing management》2009,17(5):627-635
Aims The aim of this study was to explore new nursing and midwifery roles and associated levels of practice from the health care providers' perspective. This paper will present findings relating to the perceived cost effectiveness of these roles and their impact on patient care.
Background Profound changes in the way the health care systems are organized, managed and financed have resulted in the proliferation of new nursing and midwifery roles. However, the evidence base for these workforce developments is limited, especially with regard to health care providers' perspectives on cost effectiveness and patient outcomes.
Method Qualitative interviews were carried out with all Directors of Nursing in the 18 Health and Social Services (HSS) Trusts and the Chief Nurses and Directors of Primary Care in the four HSS Boards in Northern Ireland.
Results Key findings were as follows: there was widespread support for the development of these roles, they are perceived to have a positive impact on patient care; however, the need for support was recognized to ensure the continuation of such roles. Securing funding was problematic and this was influential on the kind of new roles that were developed.
Implications for Nursing Management Issues relating to effective implementation and the need for further research into the efficacy and effectives of such initiatives is required. 相似文献
Background Profound changes in the way the health care systems are organized, managed and financed have resulted in the proliferation of new nursing and midwifery roles. However, the evidence base for these workforce developments is limited, especially with regard to health care providers' perspectives on cost effectiveness and patient outcomes.
Method Qualitative interviews were carried out with all Directors of Nursing in the 18 Health and Social Services (HSS) Trusts and the Chief Nurses and Directors of Primary Care in the four HSS Boards in Northern Ireland.
Results Key findings were as follows: there was widespread support for the development of these roles, they are perceived to have a positive impact on patient care; however, the need for support was recognized to ensure the continuation of such roles. Securing funding was problematic and this was influential on the kind of new roles that were developed.
Implications for Nursing Management Issues relating to effective implementation and the need for further research into the efficacy and effectives of such initiatives is required. 相似文献
78.
79.
80.
In an investigation into how chance might influence the distribution of deaths in a randomised trial and the time of those deaths, and to highlight the possible dangers of subgroup analyses, 100 randomised controlled trials were simulated and 50 subgroup pairs were simulated for some of these trials. Each of 580 control patients from a colorectal cancer trial was randomly coded to simulate allocation to treatment or control, the main outcome measure being time to death. Not surprisingly, most of the 100 trials gave non-significant results. Four were conventionally significant with logrank 2p-values of less than 0.05. The most extreme result was associated with a logrank 2p-value of 0.003, showing an absolute reduction in four-year mortality of 40% (SD 15) for patients allocated to treatment. One of the simulated prognostic factors for this trial (subgroup 13) showed that mortality for one type of patient was non-significantly slightly increased by treatment, whereas treatment reduced four-year mortality by 64% (SD 16) among the other patients in the trial (2p=0.00006). Similar, extreme results were found for a trial of borderline statistical significance overall. Chance can influence the overall results of any randomised controlled trial, regardless of how well it is conducted, and can play an even more powerful role in the results of subgroup analyses. This should be borne in mind both by trialists when reporting their results and by readers and reviewers of those reports. 相似文献