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The incidence and severity of catheter-induced tricuspid regurgitation has not been studied extensively. Given the frequency with which right heart catheters are employed to measure cardiac output, it is important to know whether the severity of catheter-induced tricuspid regurgitation is sufficient to invalidate the measurement of thermodilution cardiac output. Accordingly, the purpose of the present prospective study was to determine the incidence and severity of catheter-induced tricuspid regurgitation in 25 men (mean age, 58.1 +/- 1.4 years) using Doppler ultrasound. The tricuspid valve was interrogated from two orthogonal views using pulsed-wave and color flow Doppler, either in the presence or absence of a 7-French catheter across the tricuspid valve. The severity of catheter-induced tricuspid regurgitation was graded semiquantitatively using a validated scoring system. Pulsed-wave Doppler studies showed that the incidence of catheter-induced tricuspid regurgitation was 48 percent, and that the average tricuspid regurgitation score increased from 0.41 +/- 0.16 to 0.61 +/- 0.17 (p less than 0.01). Color flow Doppler studies showed similar findings. Further, the incidence of catheter-induced tricuspid regurgitation was not related to the patient's underlying hemodynamic status or right ventricular geometry. In conclusion, this study shows for the first time that the quantitative extent of catheter-induced tricuspid regurgitation is small, and is therefore unlikely to be important clinically, particularly with regard to the assessment of thermodilution cardiac output. 相似文献
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Attenders (n = 124, response rate 84%) of five GPs in Montpellier completed questionnaires on health (reason for visit, cause of problem, GHQ-12), disability (WHODAS II) and service use (CSRI). For each patient, the GP filled in a brief form including a rating of severity of physical and psychological illness. Overall 30.6% of patients were classified as GHQ cases indicating probable non-psychotic psychiatric morbidity and 58.9% were rated as having a physical illness by the GP. Patients with psychiatric morbidity showed as high levels of disability as those with a physical illness, with however a greater number of domains of life affected. They also had a greatly increased number of disability days and used services to a greater extent than those without psychiatric morbidity, these links being stronger than with physical illness. Use of the WHODAS II and the CSRI has not been previously reported in France. This study shows that they could be useful instruments for depicting disability and service use in general practice. The findings from this initial study indicate the need for greater research in primary care focusing on accurate detection and treatment of patients so that disability and excess service use associated with psychiatric morbidity might be reduced. 相似文献
25.
J A Sorenson C R Mitchell J D Armstrong H Mann D G Bragg F A Mann I B Tocino M M Wojtowycz 《Investigative radiology》1987,22(10):772-780
We evaluated the effects of unsharp masking and highly efficient scatter rejection on film-screen chest radiographs of cancer patients. Unsharp masking significantly improved the detectability of lung nodules and visibility of anatomic structures in poorly penetrated areas of the chest. Highly efficient scatter rejection by an improved antiscatter grid provided only modest additional benefits. The study supports the conclusion that nodule detection in poorly penetrated areas on conventional chest radiographs is limited primarily by display contrast, whereas in the well-penetrated lung fields it is limited primarily by confusing background structures, rather than inadequate contrast. A method for analyzing clinical nodule detection data by transforming the FROC data to ROC coordinates also is demonstrated. 相似文献
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Digital radiography of subtle pulmonary abnormalities: an ROC study of the effect of pixel size on observer performance 总被引:3,自引:0,他引:3
Forty conventional radiographs with examples of mild interstitial infiltrates and subtle pneumothoraces and 40 normal studies of the chest were selected and digitized, with pixel sizes of 1.0, 0.5, 0.2, and 0.1 mm. Observer performance tests were carried out using receiver operating characteristic analysis. Conventional radiographs and digitized images were compared. The results indicate that, in such cases, diagnostic accuracy increases significantly as the pixel size is reduced, at least to the 0.1-mm level. We conclude that, for digital systems using screen-film or similar image receptors, use of a pixel size substantially larger than 0.1 mm may result in some loss of diagnostic accuracy. 相似文献
28.
W. L. Marshall G. Serran H. Moulden R. Mulloy Y. M. Fernandez R. Mann D. Thornton 《Clinical psychology & psychotherapy》2002,9(6):395-405
In the first of the two studies reported here, we established that trained judges could reliably identify 18 therapist features that occurred with reasonable frequency. In the second study 17 of these features were examined to determine how well they related to changes in sexual offenders with treatment. Five videotapes from each of five different prison programs were rated for the presence of these 17 features and correlational analyses examined their relationship with changes in 44 measures of treatment targets. The primary findings indicated that empathy and warmth displayed by the therapists and their directive and rewarding behaviours, were the features that most strongly predicted therapeutic benefits. The results are discussed in terms of their clinical and research implications. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
29.
To test the hypothesis that angiotensin (Ang) I and II are produced by blood vessels, we investigated the formation of both Ang I and Ang II in isolated, perfused rat hindquarters. To characterize the nature of this production further, we modulated plasma renin by total or subtotal nephrectomy and tested the effects of exogenous renin and renin substrate on vascular Ang formation. Assays of the perfusate by high-performance liquid chromatography and radioimmunoassay demonstrated the spontaneous release of Ang I and Ang II from the hindlimb vasculature. Conversion of Ang I to Ang II in hindquarter vasculature was approximately 75% and was totally suppressed by captopril. The spontaneous formation of Ang peptides was abolished by bilateral nephrectomy but was not affected by subtotal 5/6 nephrectomy. The addition of purified rat angiotensinogen to the preparation increased Ang II levels. The infusion of renin into the hindlimb vasculature led to substantial increases in local Ang formation and also raised the perfusion pressure. Both effects were sensitive to captopril and to the renin inhibitor H-142. The data indicate that Ang I and Ang II are produced locally within blood vessels. However, the origin of vascular renin remains controversial. Our results suggest that part of the enzyme is taken up from plasma. 相似文献
30.
Yashpaul Sharma S. B. S. Mann R. J. Dash Y. N. Mehra 《Indian journal of otolaryngology and head and neck surgery》1987,39(4):163-166
This study was undertaken to record the Brainstem Evoked Responses in a group of 20 diabetic patients with normal hearing and were compared with responses of another group of 20 normal individuals. Eighth nerve transmission till the level of cochlear nucleus was found to be normal in diabetics. The delay in latency of Wave III, IV and V and interpeak latencies (I–III, I–V) were noted to be statistically significant, thus suggesting the presence of central neuropathy in patients with diabetes. No significant sex difference on latency of waves was observed. 相似文献