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51.
Hidden dangers of sliced bread   总被引:1,自引:0,他引:1  
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52.
Multisection, dual-echo magnetic resonance (MR) transaxial images of blood vessels contain both anatomic and qualitative information about flow. Even so, the images are produced as a series of two-dimensional tomographic sections from which full visualization of connected structures is difficult. A computer algorithm was developed that automatically detects flowing blood based on pixel intensity and calculated T2 and provides reconstructed views of vessels while analyzing and displaying flow characteristics. Images of abdominal vessels, aortic aneurysms, and the heart were encoded by flow and color to demonstrate depth. In addition, these data were reconstructed to derive a more accurate assessment of patency. With this technique, transaxial images can be used to analyze flow patterns, determine patent areas, and visualize all levels of vessels in a single image.  相似文献   
53.
The biopsychosocial model of general practice: rhetoric or reality?   总被引:4,自引:2,他引:2       下载免费PDF全文
BACKGROUND: For more than 20 years, general practitioners have been encouraged to adopt a 'biopsychosocial' model of health care, that is, encompassing physical, psychological and social aspects. AIM: A study was undertaken to explore the extent to which general practitioners' views about the acceptable boundaries of their work are consistent with a biopsychosocial model. METHOD: A semi-structured postal questionnaire was sent to all 494 members of the Royal College of General Practitioners in Mersey Region who were general practitioner principals. The general practitioners were asked to list up to three topics presented by patients that they considered to be appropriate, and up to three topics that they considered to be inappropriate, to a general practitioner's knowledge and skills. The general practitioners were asked to rate, on a five-point scale of appropriateness, each of a list of 12 topics about which patients might have problems and present. Responses were analysed by sex and age of respondents. RESULTS: The response rate was 42%. Acute physical problems were most often listed appropriate by respondents, followed by chronic physical and psychological problems. The topics most often considered inappropriate were bureaucracy and social issues. Among the list of 12 specified topics, respondents considered terminal care and hypertension to be more appropriate than housing issues, spiritual worries, welfare rights or political issues. The sex of respondents did not relate to differences in results. Respondents aged 35 years and over generally considered topics presented by their patients to be more appropriate than did their younger colleagues. CONCLUSION: The general practitioner respondents in this study appeared to hold the view that general practitioners should work to a bio(psycho) rather than a biopsychosocial model of health care.  相似文献   
54.
Summary— In recent years, two key concepts having numerous interrelationships were advanced for the understanding of various cardiovascular diseases: the “endothelial dysfunction” and the “arterial remodelling”. Both endothelial dysfunction and arterial remodelling occur in various pathologies including essential hypertension, heart failure, atherosclerosis, restenosis after angioplasty, and pulmonary hypertension, and have modified the therapeutic approach by offering new pharmacological targets: specific receptors not only at the site of the vascular smooth muscle cells but also on the endothelial cells, growth factors that stimulate proliferation of smooth muscle, and receptors and enzymes of the extra-cellular matrix. Among the various substances under research, the present review will discuss angiotensin II receptor antagonists, endothelin receptor antagonists, nitrates-NO donors, potassium channel activators, and substances interfering with proteoglycans and other components of the extra-cellular matrix.  相似文献   
55.
We instilled naphazoline Hcl (0.1%), an imidazole derivative with preferential alpha-2 activity, in 17 eyes of 12 patients with myopathic ptosis due to involvement of the levator palpebrae superioris, in the attempt to selectively stimulate Müller's smooth muscle. Naphazoline significantly widened the palpebral fissure with little change in pupillary diameter and no significant change in ocular pressure, visual acuity and near point determination. However, a reduction of the effect, probably due to tachyphylaxis, was noticed when using naphazoline regularly several times a day for few weeks. In conclusion naphazoline has powerful cosmetical and functional effects in mild to moderate myopathic ptosis above all if taken occasionally.  相似文献   
56.
Non-invasive methods for assessment of the vascular effects of antimigraine drugs were evaluated with respect to their utility, variability and sensitivity in a double-blind, placebo-controlled, three-period crossover study in six healthy volunteers using an intravenous vasoconstrictor, methoxamine, as a probe drug. Changes in the internal diameter of the brachial and radial arteries were measured using ultrasound which had low between-day and within-day coefficients of variation. Peak systolic velocity (PSV), time-averaged velocity (TAV), total flow, resistance (RI) and pulsatility indices (PI) were measured by Doppler from one arterial wave form. Whilst PSV and TAV increased with methoxamine, because of bradycardia, changes in PI and RI were difficult to interpret. An automatic oscillametric cuff, a mercury-in-silastic strain gauge method and the "Finapres", finger arterial blood pressure monitor were used to follow changes in systolic blood pressure (SBP). The strain gauge technique underestimated arm SBP compared to the oscillometric method but clearly showed drug-related increases whilst the Finapres did not reflect changes in blood pressure detected by the other methods.  相似文献   
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59.
Screening for early ovarian cancer   总被引:5,自引:0,他引:5  
Taylor  KJ; Schwartz  PE 《Radiology》1994,192(1):1
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60.
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