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131.
Dixon SR Mann JT Lauer MA Casale PN Dippel EJ Strumpf RK Feldman RL Shear W Resar JR Zimmer SD O'Neill WW;TRAP Investigators 《Journal of interventional cardiology》2005,18(4):233-241
The purpose of this prospective, multicenter trial was to evaluate the safety and effectiveness of the TRAP Vascular Filtration System (VFS) to reduce embolic complications during stenting of diseased saphenous vein grafts (SVGs). Patients with SVG lesions were randomly assigned to undergo stenting with or without the TRAP device. The trial was designed to enroll 752 randomized patients. However, the sponsor terminated the study after a total of 467 patients (358 randomized) were enrolled because of poor recruitment once another distal protection device was approved for clinical use. The primary study endpoint, major adverse cardiac events at 30 days, occurred in 17.3% of control patients and 12.7% of patients treated with the TRAP device (P = 0.24). There was a trend toward a lower incidence of myocardial infarction in the TRAP group compared with the control group (16.2% vs 10.5%, P = 0.12). This difference was predominantly due to a lower incidence of moderate-large infarction (CKMB >5x) in the TRAP group. Use of the TRAP VFS during SVG intervention was safe and was associated with a trend toward a lower incidence of adverse events, however, due to low enrollment the study lacked sufficient power to detect a significant benefit with the device. 相似文献
132.
Gheorghiade M Orlandi C Burnett JC Demets D Grinfeld L Maggioni A Swedberg K Udelson JE Zannad F Zimmer C Konstam MA 《Journal of cardiac failure》2005,11(4):260-269
BACKGROUND: Hospitalizations for worsening heart failure due to fluid overload (congestion) are common. Agents that treat congestion without causing electrolyte abnormalities or worsening renal function are needed. Tolvaptan is an oral vasopressin (V 2 ) antagonist that decreases body weight and increases urine volume without inducing renal dysfunction or hypokalemia. The Efficacy of Vasopressin antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) trial is evaluating mortality, morbidity, and patient-assessed global clinical status in patients treated with tolvaptan compared with standard care. METHODS AND RESULTS: Patients are eligible for inclusion if they have a reduced left ventricular ejection fraction and are hospitalized for worsening heart failure with evidence of systemic congestion. Patients are randomized 1:1 to tolvaptan 30 mg/day or matching placebo for a minimum of 60 days. Time to all-cause mortality and time to cardiovascular mortality or heart failure hospitalization are the coprimary end points. Patient-assessed global clinical status and quality of life are also evaluated. EVEREST will be continued until 1065 deaths occur. As of April 18, 2005, 2260 patients have been enrolled. CONCLUSION: Tolvaptan has been shown to reduce body weight in patients with worsening heart failure without inducing renal dysfunction or causing hypokalemia. The results of EVEREST will determine whether these effects translate into improved clinical outcomes. 相似文献
133.
Miniaturized chromatography systems for determining free pertechnetate and hydrolyzed reduced 99mTc levels in commercial 99mTc-labeled iminodiacetate (IDA) hepatobiliary radiopharmaceuticals were evaluated and the results compared with gel chromatography column scanning (GCS). Commercial IDA agents were evaluated including 2,6-dimethyl IDA, p-isopropyl IDA, p-butyl IDA, and 2,6-diisopropyl IDA. Of all the chromatography systems evaluated, only Gelman ITLC-SA with 20% NaCl and Gelman ITLC-SG with distilled water correlated with GCS in evaluating free pertechnetate and hydrolyzed reduced 99mTc levels for all IDA radiopharmaceuticals. The miniaturized chromatography procedure, as outlined, is rapid, taking less than 4 min, and can easily be incorporated into the daily quality control program in any nuclear medicine facility. 相似文献
134.
Heinz-Gerd Zimmer Gudrun Steinkopff Eckehart Gerlach 《Pflügers Archiv : European journal of physiology》1972,336(4):311-325
Summary Myocardial protein synthesis was studied in rats in vivo during the first five days of the development of cardiac hypertrophy induced by aortic constriction. Using l-14C-glycine or l-14C-leucine as precursor amino acids, rates of protein synthesis were determined from the total radioactivity of proteins and the mean radioactivity of the intracellular amino acid precursor pool and the leucine pool, respectively. During the first 5 h after aortic constriction the radioactivity of proteins did not change remarkably, whereas the radioactivity of the amino acid precursor pool was significantly elevated. Myocardial protein synthesis proved therefore to be diminished in this initial phase. After 24 h protein synthesis reached the range of sham-operated controls and thereafter increased almost parallel with the elevation of the ratio heart weight/body weight. The inhibition of protein synthesis was accompanied by a moderate decrease of ATP and creatine phosphate levels. A diminution of the high energy phosphate compounds, a decreased RNA synthesis or the action of inhibitory metabolites are considered possible factors involved in the decline of protein synthesis during the early phase of cardiac hypertrophy.Preliminary reports of this investigation were presented at the 36th Meeting of the German Physiological Society, Mainz, September 1969 [42] and at the XXV International Congress of Physiological Sciences, Munich, July 1971 [43].Supported by a grant from the Deutsche Forschungsgemeinschaft (Ge 129/7,8). 相似文献
135.
136.
W. Holtmeier J. Henker E. O. Riecken Prof. Dr. K.-P. Zimmer 《Monatsschrift für Kinderheilkunde》2005,153(10):969-973
Zusammenfassung Die Zöliakie weist verschiedene Verlaufsformen auf und ist in ihrem klinischen Erscheinungsbild sehr heterogen. Dies erfordert eine differenzierte Therapie und Betreuung der Patienten. Aus den Reihen des ärztlichen Beirates der Deutschen Zöliakie-Gesellschaft wurde eine Arbeitsgruppe gebildet, um die Bezeichnungen der verschiedenen Verlaufsformen der Zöliakie, die bislang uneinheitlich benutzt wurden, näher zu definieren. Durch die konsequente Beachtung und Anwendung der unterschiedlichen Definitionen der Zöliakie können Unsicherheiten beim behandelnden Arzt vermieden und hierdurch eine Vereinheitlichung und Verbesserung der Patientenversorgung erreicht werden. 相似文献
137.
138.
139.
Head and neck malignancy: is PET/CT more accurate than PET or CT alone? 总被引:15,自引:0,他引:15
Branstetter BF Blodgett TM Zimmer LA Snyderman CH Johnson JT Raman S Meltzer CC 《Radiology》2005,235(2):580-586
PURPOSE: To prospectively determine whether combined positron emission tomography (PET) and computed tomography (CT) is more accurate than either PET or CT alone in depicting malignant lesions in the head and neck. MATERIALS AND METHODS: Study was approved by the institutional review board, and patient informed consent was waived. Sixty-five consecutive patients (42 men, 23 women; age range, 43-83 years) known to have or suspected of having head and neck cancer were examined with combined PET/CT. CT was performed with intravenous administration of a contrast agent, and the CT data were used for attenuation correction. Each examination was interpreted in three ways: PET images in the absence of CT data, CT images in the absence of PET data, and fused PET/CT images. Probability of malignancy of each lesion was assigned a score by using a five-point scale. Receiver operating characteristic (ROC) analyses were performed by using biopsy, imaging, or clinical follow-up as the reference standard. The minimum follow-up was 6 months (range, 6-12 months). The results were additionally analyzed to assess the degree of radiologist confidence. RESULTS: Follow-up was available for 64 (98%) of 65 patients. ROC analyses demonstrated that PET/CT is significantly superior to PET or CT alone for depiction of malignancy in the head and neck (P < .05). In this series, PET/CT had a sensitivity of 98%, a specificity of 92%, and an accuracy of 94%. Radiologist confidence was substantially higher with the combined modality. CONCLUSION: Combined PET/CT is more accurate than PET or CT alone for the depiction of malignancy in the head and neck. Radiologist confidence is improved with the combined modality. 相似文献
140.
Warmuth C Rüping M Förschler A Koennecke HC Valdueza JM Kauert A Schreiber SJ Siekmann R Zimmer C 《AJNR. American journal of neuroradiology》2005,26(5):1035-1043
BACKGROUND AND PURPOSE: Similar to digital subtraction angiography, dynamic spin labeling angiography (DSLA) provides time-resolved measurements of the influx of blood into the cerebral vascular tree. We determined whether DSLA may help in assessing the degree of stenosis and whether it provides information about intracerebral collateralization and allows us to monitor the hemodynamic effects of vascular interventions. METHODS: We developed a segmented DSLA sequence that allowed the formation of images representing inflow delays in 41-ms increments. Thirty patients with unilateral carotid artery stenosis and 10 control subjects underwent DSLA. Arrival times of the labeled arterial blood bolus were measured in the carotid siphon (CS) and the middle cerebral artery (MCA) on both sides, and the corresponding side-to-side arrival time differences (ATDs) were calculated. ATDs before and after carotid endarterectomy or percutaneous angioplasty were studied in 10 patients. RESULTS: The degree of stenosis was significantly correlated with ATD in the cerebral vessels. Receiver operating characteristic analysis yielded a cutoff CS ATD of 110 ms to separate stenoses <70% from those > or =70%, with a sensitivity of 90% and a specificity of 67%. In one third of patients, ATD was higher in the MCA than in the CS; this finding suggested an absence of collateralization. Most patients had reduced ATD in the MCA. The degree of ATD reduction was regarded as a quantitative measure of collateralization. Successful intervention resulted in normalized ATDs. CONCLUSION: DSLA is a promising method that allowed us to noninvasively quantify the hemodynamic effect of extracranial carotid stenosis and the resulting intracranial collateralization. 相似文献