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1.
To investigate the impact of staged therapy for advanced heart failure on therapeutic endpoints, 236 consecutive patients (coronary artery disease/dilated cardiomyopathy in 61/175 patients, left ventricular ejection fraction 14%± 5%, New York Heart Association Class IIl/IIIIV in 102/79/55 patients, respectively) with advanced heart failure were prospectively followed. One hundred thirtyseven patients enrolled from January 1989 to December 1991 were treated conventionally with digoxin, furosemide, and low dose angiotension converting enzyme (ACE) inhibition. Patients refractory to this therapy underwent urgent heart transplantation. Ninetynine patients enrolled from January 1992 to August 1993 underwent staged therapy: stage 1: maximal tolerated ACE inhibition; stage 2: therapy with PGE1 for preand afterload reduction to achieve hemodynamic stabilization; or stage 3: refractory patients bridged to heart transplantation with continuous outpatient dobutamine. Sudden death was defined as death within 1 hour of symptoms if heart failure symptoms remained stable over the previous 7 days. Conventionally treated patients were followed for 10 ± 9 months; patients who underwent staged therapy for 9 ±5 months. In the group of patients that underwent standard therapy, 39 of 137 (28%) patients died: 5 (13%) deaths occurred suddenly, and death due to progressive pump failure occurred in the remaining 34 (87%) patients. In the group of patients that underwent staged therapy, 25 of 99 (25%) patients died: 13 (52%) deaths occurred suddenly, and 12 (48%) deaths occurred due to progressive pump failure. Thus, patients who underwent staged therapy were at increased risk for sudden death (P = 0.01, relative risk 3.4, 95% confidence interval 1.2–9.7) but were at lower risk for death from pump failure (P = 0.009, relative risk 0.44, 95% confidence interval 0.22–0.84). In patients who underwent therapy with continuous outpatient PGE1 (n = 7) or dobutamine (n= 21), risk for sudden death (P = NS by log rank test) did not increase. In conclusion, staged therapy significantly reduced death from pump failure; however, patients who could be stabilized and considered too well for heart transplantation were at increased risk for sudden death. Thus, overall survival did not improve. Of note, outpatient dobutamine did not increase the risk for sudden death.  相似文献   
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Alveolar surfactant is well known for its ability to reduce minimal surface tension at the alveolar air–liquid interface to values below 5 mN m?1. In addition, it has been suggested that surfactant is also present in the airways, particularly in the perinatal period. We isolated surfactant from pharyngeal aspirates obtained from 33 neonates immediately after delivery and analysed it for both phospholipid (PL) composition and surface tension function. PL classes and phosphatidylcholine (PC) molecular species were determined by normal and reversed-phase high-performance liquid chromatography (HPLC), respectively. Static and dynamic surface properties of the surfactant were studied in a pulsating bubble surfactometer. Sample volume was 1.3 ± 0.5 mL (mean ± SD) with a total amount of 2.5 ± 1.3 μmol of PL and a concentration of 2.1 ± 1.0 μmol mL?1 PL. HPLC analyses of PL classes revealed a composition identical with surfactant prepared from alveolar washes, i.e. PC 83.6 ± 2.1%, sphingomyelin 1.4 ± 0.5%, phosphatidylglycerol 8.1 ± 1.6%, phosphatidylethanolamine 2.1 ± 0.5% and phosphatidylinositol 2.6 ± 1.1%. Thin-layer chromatography showed almost identical results but was more time-consuming and needed more material for analysis. Analysis of PC molecular species revealed a composition typical of human alveolar surfactant with 54.7 ± 3.9% dipalmitoyl PC, 10.3 ± 1.9% palmitoyloleoyl PC and 9.1 ± 1.5% palmitoylmyristoyl PC. Minimal surface tension fell to values below 5 mN m?1 within 5 min of cycling in all subjects. The methods used in this study allowed for complete PL and surface tension analyses of surfactant obtained during routine pharyngeal suctioning after delivery at term. Whether they are also applicable to preterm neonates with respiratory distress remains to be determined.  相似文献   
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Background: Prevalence of patent foramen ovale (PFO) with detectable right‐to‐left shunt is higher in young adults with transient ischemic attack (TIA) and stroke compared to the general population. So far, published series included different occluder systems, various indications and regimens of postprocedural anticoagulation. In our experience, occluder systems may be associated with an increased prevalence of thrombus formation, which has also reported by other groups. The aim of the present study was to evaluate the follow‐up results after implantation of the Amplatzer® occluder in patients with PFO using a consistent anticoagulation regimen. Methods and Results: One‐hundred and fourteen patients with PFO (60 men; age: 47 ± 13 years) and ≥1 thromboembolic event were included. Other causes for embolism were excluded. PFO‐closure was successful in all patients. All patients were treated with aspirin (100 mg/day) and clopidogrel (75 mg/day) for 6 months. TEE was repeated at a mean of 10.3 months. Mean clinical follow‐up period was 18 ± 9 months. After a mean of 10 months, no patient had either a significant residual shunt nor a suspected thrombus formation on the occluder. During follow‐up, 5 patients suffered from neurological events (1 stroke, 2 TIAs, 2 epileptic seizures), though complete closure of the PFO was documented by TEE. One patient suffered from bleeding complications (upper GI‐bleeding). Conclusion: Percutaneous closure of PFO in symptomatic patients by Amplatzer® occluder represents an effective therapy with a low incidence of peri‐interventional complications and recurrent thromboembolism. Thrombus formations on the occluder system were not detected in this cohort. (J Interven Cardiol 2011;24:85–91)  相似文献   
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ABSTRACT An ultrasensitive thyrotropin (TSH) assay was used to determine how many of 65 patients with primary hypothyroidism on thyroxine (T4) replacement therapy had suppressed serum TSH. In 13 patients (20%) TSH levels ≤0.1 mlU/l were found, indicating an overdose of thyroxine. After correction of the dose, 48 patients had normal TSH values. Their mean dose of thyroxine was 119 μg/24 hours, and the appropriate replacement dose tended to decline with advancing age. The serum level of thyroid hormones during replacement therapy with thyroxine very imperfectly reflected serum TSH values. It is concluded that overdose of thyroxine is common when suppressed serum TSH is used as an end point. Biochemical follow-up of replacement therapy with thyroxine in primary hypothyroidism therefore requires the use of an ultrasensitive TSH assay in order to detect such suppression. Serum levels of thyroxine or triiodothyronine (T3) during thyroxine therapy are poor indicators of pituitary TSH secretion and are therefore not useful as parameters of adequate thyroxine dosage.  相似文献   
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The skeletal muscle dihydropyridine receptor is a slowly-activating calcium channel that functions as the voltage sensor in excitation-contraction coupling. In addition to the pore-forming α1S subunit it contains the transmembrane α2δ-1 and γ1 subunits and the cytoplasmic β1a subunit. Although the roles of the auxiliary subunits in calcium channel function have been intensively studied in heterologous expression systems, their functions in excitation-contraction coupling has only recently been elucidated in muscle cells of various null-mutant animal models. In this article we will briefly outline the current state of these investigations. * To whom correspondence should be addressed: Tel.: +43-512-507-3787; Fax: +43-512-507-2836; E-mail: bernhard.e.flucher@uibk.ac.at  相似文献   
7.
Using pulse oximetry and Holter ECG monitoring on the nightbefore coronary bypass surgery, we studied 30 male patientswith coronary artery disease to determine the relationship betweennocturnal hypoxaemia and myocardial ischaemia. The patientsreceived intensive anti-angina medication and were sedated withclorazepate. Ten patients developed a total of 42 ischaemicepisodes, 24 of which occurred between 22:00 and 06:00. Meanheart rate was significantly higher in patients with ischaemiathan in those without ischaemia. In 60% of all patients, heartrate increased  相似文献   
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Electron microscopy of tumor cells and tumor viruses; a review   总被引:32,自引:0,他引:32  
BERNHARD W 《Cancer research》1958,18(5):491-509
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