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1.
Dr. Carsten Rist T.R. Johnson A. Becker A.W. Leber A. Huber S. Busch C.R. Becker M.F. Reiser K. Nikolaou 《Der Radiologe》2007,47(4):287-294
In a newly developed dual-source computed tomography system (DSCT) the relation of heart rate and image quality and the possible advantages of the system’s superior temporal resolution in the evaluation of left ventricular parameters as compared to results of cardiac magnetic resonance imaging (MRI) were assessed. Coronary CT angiography was performed using a DSCT (Somatom Defintion, Siemens Medical Solutions, Forchheim, Germany) in 21 patients (mean age 62±8; 15 male, 6 female). Image quality of the coronary arteries, the heart valves, and the left ventricular myocardium was assessed using a three-point grading scale. Ten of these patients also underwent cardiac MRI for the assessment of left ventricular function, using a SSFP (steady-state free precession) sequence. Left ventricular ejection fractions (LV-EF), the end-systolic volumes (ESV), and the end-diastolic volumes (EDV) were measured employing MRI and DSCT datasets. The image quality ratings for the coronary arteries at the optimal reconstruction interval were diagnostic even in patients with high heart rates (1.42±0.49). Analysis of global LV function using DSCT quantified from CTA datasets showed a good correlation with results of cardiac MRI [EF: r=0.75 (p=0.01); ESV: r=0.72 (p=0.19); EDV: r=0.71 (p=0.02)]. The dual-source CT system offers robust image quality of the coronary arteries, independent of the heart rate, and provides combined diagnostic imaging of coronary arteries, the heart valves, the myocardium, and the global left ventricular function. 相似文献
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Screening asymptomatic women in the general population for 'early ovarian ageing' will be more effective in high-risk groups. Recent findings support the hypothesis that women with polycystic ovaries (PCO) may have actually been born with a larger pool of resting follicles. The mechanism is almost certainly genetic and occurs in fetal life. If, as is widely accepted, the rate of depletion of the ovarian reserve depends primarily on the size of the remaining pool of small follicles, women with PCO will be unlikely to undergo an accelerated depletion of their follicle pool, normally seen in the late thirties, significantly earlier. In terms of asymptomatic screening for early ovarian ageing in the general population, women with PCO constitute a low-risk group and should therefore be excluded. 相似文献
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D Pectasides M Pectasides D Farmakis V Kostopoulou M Nikolaou A Gaglia M Koumpou N Mylonakis N Xiros T Economopoulos S A Raptis 《Annals of oncology》2005,16(2):294-299
BACKGROUND: The aim of this study was to evaluate whether docetaxel (taxotere) treatment with or without irinotecan improved patient outcomes with similar toxicity in recurrent non-small-cell lung cancer (NSCLC). PATIENTS AND METHODS: Patients with recurrent platinum-refractory NSCLC with Eastern Cooperative Oncology Group performance status of 0-2 were randomized to either docetaxel 30 mg/m(2) and irinotecan 60 mg/m(2) (days 1 and 8) or docetaxel 75 mg/m(2) (day 1), both administered every 3 weeks. RESULTS: A total of 130 patients were randomized. The response rate (RR) (20% versus 14%), overall survival (6.5 months versus 6.4 months) and 1-year survival (37% versus 34%) were similar in the combination and docetaxel arms, respectively. The combination arm demonstrated a longer time to tumor progression (TTP) (5.6 versus 4.8 months; P=0.065). Grade 3-4 neutropenia and anemia were similar in the combination and docetaxel arms. Grades 3-4 non-hematological toxicity (except diarrhea) was mild and was similar in the two groups. Grade 3-4 thrombocytopenia (17% versus 6%; P=0.04) and diarrhea (12% versus 3%; P=0.05) occurred more frequently in the combination arm. CONCLUSIONS: The administration of irinotecan with docetaxel in platinum-refractory NSCLC prolonged TTP, but did not improve significantly RR, median survival or 1-year survival. Second-line docetaxel monotherapy offers significant and reproducible efficacy in platinum-refractory NSCLC. 相似文献
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Inclusion compounds of Al-quercetin and Al-catechin complexes with β-cyclodextrin (βCD) were investigated. The complex and the inclusion compound of quercetin are more effective DPPH? scavengers than the corresponding catechin compounds and the inclusion does not compromise their scavenging abilities, with only a slight decrease in the EC50 values. This is in accordance with the electrochemical data, which revealed that the inclusion compounds have lower diffusion coefficients in aqueous solution than the non-included compounds. For the quercetin compounds, some spectroscopic properties were also addressed by means of UV–visible and NMR measurements in aqueous media. 相似文献
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Phototherapy as a first‐line treatment for early‐stage mycosis fungoides: The results of a large retrospective analysis 下载免费PDF全文
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Birth defect-related demise is mainly due to congenital heart defects. In the earlier stage of pregnancy, fetus problem can be identified by finding information about the fetus to avoid stillbirths. The gold standard used to monitor the health status of the fetus is by Cardiotachography(CTG), cannot be used for long durations and continuous monitoring. There is a need for continuous and long duration monitoring of fetal ECG signals to study the progressive health status of the fetus using portable devices. The non-invasive method of electrocardiogram recording is one of the best method used to diagnose fetal cardiac problem rather than the invasive methods.The monitoring of the fECG requires development of a miniaturized hardware and a efficient signal processing algorithms to extract the fECG embedded in the mother ECG. The paper discusses a prototype hardware developed to monitor and record the raw mother ECG signal containing the fECG and a signal processing algorithm to extract the fetal Electro Cardiogram signal. We have proposed two methods of signal processing, first is based on the Least Mean Square (LMS) Adaptive Noise Cancellation technique and the other method is based on the Wavelet Transformation technique. A prototype hardware was designed and developed to acquire the raw ECG signal containing the mother and fetal ECG and the signal processing techniques were used to eliminate the noises and extract the fetal ECG and the fetal Heart Rate Variability was studied. Both the methods were evaluated with the signal acquired from a fetal ECG simulator, from the Physionet database and that acquired from the subject. Both the methods are evaluated by finding heart rate and its variability, amplitude spectrum and mean value of extracted fetal ECG. Also the accuracy, sensitivity and positive predictive value are also determined for fetal QRS detection technique. In this paper adaptive filtering technique uses Sign-sign LMS algorithm and wavelet techniques with Daubechies wavelet, employed along with de noising techniques for the extraction of fetal Electrocardiogram.Both the methods are having good sensitivity and accuracy. In adaptive method the sensitivity is 96.83, accuracy 89.87, wavelet sensitivity is 95.97 and accuracy is 88.5. Additionally, time domain parameters from the plot of heart rate variability of mother and fetus are analyzed. 相似文献