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排序方式: 共有907条查询结果,搜索用时 15 毫秒
91.
92.
R. Hamdan Z. Kadri R. Kassab S. Abou Jaoudé 《Annales de cardiologie et d'angeiologie》2010,59(1):34-36
Cerebral hemorrhage is usually associated to many cardiac disorders, mimicking acute coronary syndrome. We relate a case of a postmenopausal woman presenting at emergency room for acute coronary syndrome and whose evaluation revealed a subarachnoidal hemorrhage, normal coronary arteries, and a typical Tako Tsubo aspect on echocardiography with apical ballooning and hyperkinesis with basal hypokinesis. 相似文献
93.
Nadeau V O'Dwyer M Hamdan K Tait I Padgett M 《Photodermatology, photoimmunology & photomedicine》2004,20(4):170-174
BACKGROUND: In recent years, 5-aminolaevulinic acid (ALA) has become an increasingly popular photosensitizing drug for use in both photodynamic therapy (PDT) and photodetection (PD) of cancers. ALA metabolizes within tissue to form the photosensitizer protoporphyrin IX (PpIX). Like most photosensitizers, PpIX is fluorescent, and this fluorescence progressively decreases during PDT. This phenomenon is referred to as photobleaching. AIM: Our aim in carrying out this experiment was twofold: firstly, to compare the relative capacity of red and blue light to cause photobleaching; and secondly, to compare the capacity of a fixed light dose to cause photobleaching, when delivered at different intensities. METHOD: In this paper, we describe the implementation of a compact fluorescence spectrometer in monitoring the photobleaching of ALA-induced PpIX in vivo on the skin of healthy volunteers. RESULTS: We have been able to show that blue light causes more rapid photobleaching than red light, and that under illumination with red or blue light, delivery of a fixed light dose at a lower intensity results in more photobleaching. CONCLUSION: Comparison of the photobleaching rates suggests that a blue light intensity of 5 mW/cm(2) gives the same rate of photobleaching as the typical red light PDT intensity of 100 mW/cm(2). Further investigation of the correlation between PpIX photobleaching and PDT effect would be beneficial in interpreting the clinical significance of our findings. 相似文献
94.
95.
S Kelle A Hamdan B Schnackenburg U K?hler C Klein E Nagel E Fleck 《Journal of cardiovascular magnetic resonance》2008,10(1):44
Purpose
The assessment of inducible wall motion abnormalities during high-dose dobutamine-stress cardiovascular magnetic resonance (DCMR) is well established for the identification of myocardial ischemia at 1.5 Tesla. Its feasibility at higher field strengths has not been reported. The present study was performed to prospectively determine the feasibility and diagnostic accuracy of DCMR at 3 Tesla for depicting hemodynamically significant coronary artery stenosis (≥ 50% diameter stenosis) in patients with suspected or known coronary artery disease (CAD).Materials and methods
Thirty consecutive patients (6 women) (66 ± 9.3 years) were scheduled for DCMR between January and May 2007 for detection of coronary artery disease. Patients were examined with a Philips Achieva 3 Tesla system (Philips Healthcare, Best, The Netherlands), using a spoiled gradient echo cine sequence. Technical parameters were: spatial resolution 2 × 2 × 8 mm3, 30 heart phases, spoiled gradient echo TR/TE: 4.5/2.6 msec, flip angle 15°. Images were acquired at rest and stress in accordance with a standardized high-dose dobutamine-atropine protocol during short breath-holds in three short and three long-axis views. Dobutamine was administered using a standard protocol (10 μg increments every 3 minutes up to 40 μg dobutamine/kg body weight/minute plus atropine if required to reach target heart rate). The study protocol included administration of 0.1 mmol/kg/body weight Gd-DTPA before the cine images at rest were acquired to improve the image quality. The examination was terminated if new or worsening wall-motion abnormalities or chest pain occurred or when > 85% of age-predicted maximum heart rate was reached. Myocardial ischemia was defined as new onset of wall-motion abnormality in at least one segment. In addition, late gadolinium enhancement (LGE) was performed. Images were evaluated by two blinded readers. Diagnostic accuracy was determined with coronary angiography as the reference standard. Image quality and wall-motion at rest and maximum stress level were evaluated using a four-point scale.Results
In 27 patients DCMR was performed successfully, no patient had to be excluded due to insufficient image quality. Twenty-two patients were examined by coronary angiography, which depicted significant stenosis in 68.2% of the patients. Patient-based sensitivity and specificity were 80.0% and 85.7% respectively and accuracy was 81.8%. Interobserver variability for assessment of wall motion abnormalities was 88% (κ = 0.760; p < 0.0001). Negative and positive predictive values were 66.7% and 92.3%, respectively. No significant differences in average image quality at rest versus stress for short or long-axis cine images were found.Conclusion
High-dose DCMR at 3T is feasible and an accurate method to depict significant coronary artery stenosis in patients with suspected or known CAD. 相似文献96.
This is the second case report in literature that describes the simultaneous acoustic cardiographic, electrocardiographic, and invasive hemodynamic events that occurred before, during and after ventricular fibrillation that was successfully cardioverted to sinus rhythm. The absence of heart sounds, which are linked to the lack of effective myocardial contractility, correlated well with invasive hemodynamic data, indicating the lack of perfusion during ventricular fibrillation. These observations, coupled with the challenges of pulse detection as a sign of adequate perfusion during resuscitation suggest that acoustic cardiography may be a potentially effective supplemental diagnostic tool during the resuscitation of malignant arrhythmias. 相似文献
97.
Shrikhande GV Hamdan AD Monahan TS Pomposelli FB Scovell SD Logerfo FW Schermerhorn M 《World journal of surgery》2007,31(12):2422-2426
Background With the advent of endovascular therapy for lower extremity ischemia it is important to better determine what factors may
affect the outcome. The goal of the present study was to evaluate whether ejection fraction (EF) is predictive of outcome
in infrainguinal arterial reconstruction.
Methods We retrospectively reviewed 736 patients undergoing 897 infrainguinal arterial reconstructions from July 1999 to February
2002. Patients were divided into two groups: group I contained 54 patients with an EF<35% and group II had 216 patients with
an EF ≥35%. The outcome evaluated was major adverse clinical events (MACEs), defined as postoperative myocardial infarction
(MI), arrhythmia, congestive heart failure (CHF), and perioperative mortality.
Results Major adverse clinical events occurred in 20.3% of patients (11/54) in group I and 10.6% patients (23/216) in group II (p = 0.068). Group I had a trend toward a greater incidence of MACEs compared to group II. Two-year survival for group I was
61.7%, whereas survival for group II was 78.4% (p = 0.0085).
Conclusions Low EF predicts a significantly shortened 2-year survival after infrainguinal arterial reconstruction and a trend toward increased
perioperative complications. This is another factor to be considered in choosing open versus endovascular options. 相似文献
98.
Voice production is a complex process that involves more than one system, yet most causes of dysphonia are attributed to disturbances in the laryngeal structures and little attention is paid to extralaryngeal factors. Persistent dysphonia after general anesthesia is a challenge to both anesthesiologists and otolaryngologists. The etiology is often multivariable and necessitates a team approach for proper diagnosis. Laryngeal symptoms are subdivided into phonatory disturbances and airway related complaints. When they become persistent for more than 72 hours or are coupled with airway symptoms such as hemoptysis, stridor, dyspnea or aspiration, the anesthesiologist should suspect injury to the vocal folds or cricoarytenoid joints. Here-below, the laryngeal manifestations of endotracheal intubation and the pathophysiology of vocal fold scarring are discussed. 相似文献
99.
100.
Cogliati AA Vellutini R Nardini A Urovi S Hamdan M Landoni G Guelfi P 《Journal of cardiothoracic and vascular anesthesia》2007,21(6):847-850
OBJECTIVE: The purpose of this study was to evaluate the renoprotective effects of fenoldopam in patients at high risk of postoperative acute kidney injury undergoing elective cardiac surgery requiring cardiopulmonary bypass. DESIGN: A double-blind randomized clinical trial. Setting: Hospital. Participants: One hundred ninety-three patients. Interventions: Patients undergoing cardiac surgery were randomly assigned to receive a continuous infusion of fenoldopam, 0.1 microg/kg/min (95 patients), or placebo (98 patients) for 24 hours. Patients were included if at least 1 of the following risk factors was present: preoperative serum creatinine > or =1.5 mg/dL, age >70 years, diabetes mellitus, or prior cardiac surgery. Serum creatinine and urinary output were measured at baseline (T1), 24 hours (T2), and 48 hours after surgery (T3). Acute kidney injury was defined as a postoperative serum creatinine level of > or =2 mg/dL with an increase in serum creatinine level of 0.7 mg/dL or greater from preoperative to maximum postoperative values. MEASUREMENTS AND MAIN RESULTS: Acute kidney injury developed in 12 of 95 (12.6%) patients receiving fenoldopam and in 27 of 98 (27.6%) patients receiving placebo (p = 0.02), whereas renal replacement therapy was started in 0 of 95 and 8 of 98 (8.2%) patients, respectively (p = 0.004). Serum creatinine was similar at baseline (1.8 +/- 0.4 mg/dL v 1.9 +/- 0.3 mg/dL) in the fenoldopam and placebo groups but differed significantly (p < 0.001 and p < 0.001) 24 hours (1.6 +/- 0.2 mg/dL v 2.5 +/- 0.6 mg/dL) and 48 hours (1.5 +/- 0.3 mg/dL v 2.8 +/- 0.4 mg/dL) after the operation. CONCLUSIONS: A 24-hour infusion of 0.1 mug/kg/min of fenoldopam prevented acute kidney injury in a high-risk population undergoing cardiac surgery. 相似文献