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71.
The effectiveness of an antiarrhythmic drug is judged by the degree of ventricular arrhythmia (VA) suppression. We evaluated the relationship between the degree of VA suppression and survival in a dose-adjusted trial of 110 symptomatic patients treated with amiodarone. Cohorts had left-ventricular ejection fraction (LVEF) of 41 plus minus 18%, ventricular premature contractions (VPCs) of 445 plus minus 571 h, couplets (C) of 733 plus minus 1498 24 h and nonsustained (N) ventricular tachycardia (VT) of 65 plus minus 217 24 h; these conditions were followed for 15 plus minus 11.5 months. Amiodarone was initiated with an oral loading of 670 plus minus 111.7 mg per day for 10 days and continued on maintenance of 274.9 plus minus 102 mg per day. Survival rates of responders and nonresponders with VPCs <70%, 70--89%, greater-than-or-equal90%; C greater-than-or-equal 90%; NVT (100%); and the response to all 3 criteria (suppresion of VPCs greater-than-or-equal70%, C greater-than-or-equal 90% and complete abolition of NVT) were not statistically significant. Survival rates as a function of LVEF <40% (51 patients) or greater-than-or-equal40% (59 patients), as well as responders or nonresponders to all three criteria, were not significant (p = NS). We conclude that, in patients treated with low-dose amiodarone, the degree of VA suppression of PVCs, C and NVT does not predict survival; the survival of patients with LVEF <40% improved irrespective of VA suppression; and criteria for VA suppression should be reassessed at lower levels of suppression for the improvement of the drug risk:benefit ratio. More improvement is not necessarily better. 相似文献
72.
Development and validation of the Diabetes Care Profile 总被引:7,自引:0,他引:7
Fitzgerald JT Davis WK Connell CM Hess GE Funnell MM Hiss RG 《Evaluation & the health professions》1996,19(2):208-230
To determine the reliability and the validity of the Diabetes Care Profile (DCP), an instrument that assesses the social and psychological factors related to diabetes and its treatment, two studies with separate populations and methodologies were conducted. In the first study, the DCP was administered to, and physiologic measures collected from, individuals with diabetes being cared for in a community setting (n = 440). In the second study, the DCP and several previously validated scales were administered to individuals with diabetes receiving care at a university medical center (n = 352). Cronbach's alphas of individual DCP scales ranged from .60 to .95 (Study 1) and from .66 to .94 (Study 2). Glycohemoglobin levels correlated with three DCP scales (Study 1). Several DCP scales discriminated among patients with different levels of disease severity. The results of the studies indicate that the DCP is a reliable and valid instrument for measuring the psychosocial factors related to diabetes and its treatment. 相似文献
73.
Most of us agree that people are our most important resource. Yet we spend a minimal amount of time learning more about human behavior, communication, and how our attitudes and behavior impact employee performance. Instead we rely on traditional methods of negative reinforcement in an attempt to control our areas of responsibility. While these methods can render some short-term success, managers and organizations that succeed during these times of change and fierce competition will be those that take the time to understand and capture the power of a committed workforce. The committed workforce is energized, not simply compliant, as a result of having basic human needs for achievement satisfied, belonging to a group, and receiving recognition for its contributions. Committed workers typically describe the manager as one who has the ability to give them a great degree of control over their area of influence. We all know that we don't change our leadership style like we change clothes. Old habits die hard. it takes a personal commitment and lots of practice to rid outselves of habits and behavior that no longer serve our departments and facilities. This commitment, however, is crucial to survival. As managers, we must cope with increasing ambiguity and uncertainty in the workplace. To survive these challenges, we must improve our interpersonal skills and ability to successfully bring out the best in others. I believe that success will continue for managers who not only increase their knowledge and technical ability, but who also inspire their workers to move forward with a collective sense of enthusiasm and purpose. 相似文献
74.
Vision through cataracts 总被引:11,自引:0,他引:11
Contrast thresholds for a range of different spatial frequencies were compared with "acuity" tests for 10 subjects with uniocular senile cataract. The results indicate that the magnitude and extent of the intra-resolution limit abnormality vary dramatically in cataract subjects and that, for some subjects, vision is abnormal for objects of all sizes. This finding indicates that the present acuity evaluation of vision with cataracts is inadequate because, in some cases, it grossly overestimates the nature of the visual world of the cataract patient. 相似文献
75.
The effect of temporal frequency variation on threshold contrast sensitivity deficits in optic neuritis. 总被引:5,自引:3,他引:2 下载免费PDF全文
The effect of increasing temporal frequency on contrast sensitivity anomalies in unilateral optic neuritis has been investigated. For 4 c/deg gratings no change in the deficit was observed at any temporal frequency whereas there was a tendency for the deficit to decrease with increase in temporal frequency for 0-5 c/deg gratings. The latter effect was not observed in a case of optic neuritis with severe deficit and not in two cases of other optic nerve pathology. An explanation based on the assumption that "threshold scotomata" might be present in cases of demyelinating optic nerve disease is proposed. 相似文献
76.
We asked the question "is the visual field temporally homogeneous when the well known spatial inhomogeneity is taken into account?" Our results show that the visual field exhibits inhomogeneity for stimuli of low spatial frequency for which the spatial inhomogeneity is minimal. This inhomogeneity takes the form of a reduction in sensitivity for stimuli of low temporal frequency in the periphery and an enhancement of sensitivity for stimuli of high temporal frequency in the periphery. The low temporal frequency loss in the periphery is post-receptoral and must involve a selective loss of sensitivity of the low pass filter. The enhanced high frequency sensitivity may be post-receptoral or purely receptoral. The consequence of such an inhomogeneity for subsequent stages of visual processing is discussed. 相似文献
77.
In summary, let's review the result of the Joneses' coordinated retirement income and estate planning strategy: 1. The Joneses maximized their estate assets, converting an inefficient estate asset to an efficient estate asset, without jeopardizing their current or future standard of living. 2. They committed to a gifting program for only 10 years, after which they have the flexibility to continue gifting the trust or to retain all the current IRA income. 3. They are free to "consume" their other taxable assets during their lifetimes without worrying about saving something for their three children. The Wealth Replacement Trust will leave approximately $1 million for each child. This strategy is obviously not available to everyone, nor is it applicable to everyone. While this solution worked extremely well for these clients, everyone's situation is different. Every situation needs a professional and personalized plan based upon individual objectives. Only after objectives have been clearly identified and alternatives thoroughly explored can a suitable solution be identified. It is important that a thorough review of the entire financial picture be performed by a competent financial planning team before you attempt to correct a potential problem. Make certain your advisers are familiar with solving this type of problem so as not to create additional problems. 相似文献
78.
79.
Statins represent a promising class of agents to prevent stroke. In randomized trials of middle-aged patients with coronary artery disease, statins reduce the incidence of stroke. The reduction in stroke may not be solely related to cholesterol or low-density lipoprotein reduction but may involve nonsterol mechanisms effects on endothelial cells, macrophages, platelets, and smooth muscle cells. Statins also reduce the size of cerebral infarction in a murine stroke model, suggesting a neuroprotective effect. The best current evidence for stroke prevention is with pravastatin and simvastatin. Pravastatin reduces the risk of stroke in patients with coronary artery disease and average cholesterol levels; simvastatin reduces the risk of the combined endpoint of stroke and transient ischemic attack in hypercholesterolemic patients with coronary artery disease. Future studies of statins are needed in stroke populations, particularly the elderly. 相似文献
80.