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81.
35 consecutive patients were studied prospectively with respect to echocardiographic left ventricular size after anterior myocardial infarction. In 25 patients sufficient follow-up was possible. Another 57 patients and volunteers were examined to prove accuracy in comparison to angiocardiography and nuclear magnetic resonance imaging and reproducibility as well as to define normal values. While two-thirds of all patients did not develop left ventricular dilation, one-third showed marked dilation with left ventricular size being 41% above mean normal value. All patients who subsequently developed congestive heart failure or died were in this group. Two-thirds showed no left ventricular dilation and had an uneventful follow-up. Mean left ventricular dilation for all infarcts was 22% within 4 weeks and 26% within 6.3 months, but some patients showed marked left ventricular dilation beyond 4 weeks. We conclude that serial echocardiography is very useful for stratification of risk for CHF after myocardial infarction, and left ventricular dilation is a major risk factor for CHF.  相似文献   
82.
A soluble, NADP+-dependent alcohol dehydrogenase (ADH) with a pH optimum at 8.7 was found in A. calcoaceticus EB 104 after growth on different carbon sources. n-Alkanols with short and medium chain length were employed as test substrates. The Km values decreased with increasing chain length. The Vmax values remained nearly unchanged. The activities determined were independent of the carbon source. Furthermore, a n-alkanol-dependent reduction of DCPIP was measured in membrane fractions of cells grown on different carbon sources. The optimum pH for this reaction was at 7.5. Further proof for the presence of a pyridine nucleotide-independent ADH was derived from the oxidation of 14C-decanol in the absence of NADP+ or NAD+.  相似文献   
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84.
Traumatic thoracic aortic transection (TTAT) results from a high positive or negative G force exerted on the body. It is associated with a high rate of lethality. Precipitating events are especially traffic accidents in which the patients have usually sustained multiple injuries, and traumatic rupture of the aorta represents the second most frequent cause of death after head injuries. While clinical examinations and conventional diagnostic radiology only suggest the presence of TTAT, it can be reliably diagnosed with the aid of multidetector-row computed tomography (CT). Consequent to the successful introduction of implantable endovascular stent grafts to repair various forms of aortic aneurysms, this method has become an established approach to treating traumatic transections and has to a large extent replaced open surgery with its inherently high morbidity and mortality. Endovascular therapy has been successfully performed at the UKB in eight patients with TTAT since 2006. While one patient died from septic multiorgan failure, no procedural complications were observed. An occurrence of endoleak could be excluded in all cases based on CT monitoring.  相似文献   
85.
86.
Venous clots: evaluation with MR imaging   总被引:2,自引:0,他引:2  
In vitro and in vivo studies were performed to determine the proton relaxation and imaging characteristics of static blood and acute and organized clot in canine jugular veins. In vivo, it was found that two inversion recovery sequences using a short inversion time (100 msec) demonstrated better differentiation of signal intensity of intravascular clot from surrounding soft tissues than did standard T1- and T2-weighted sequences. In vitro, quantitative measurements showed marked reduction of both T1 and T2 relaxation time of acute clot compared with stagnant blood. In addition, the T1 relaxation time, and to a lesser extent the T2 relaxation time, shortened as the clot aged, indicating a potential role for magnetic resonance imaging in determining the age of venous thrombi.  相似文献   
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88.
Two different methods for assessing psychopathology in opiate addicts were compared as predictors of long-term treatment outcome: (1) categorical psychiatric diagnosis using the Schedule for Affective Disorders and Schizophrenia--Lifetime Version and the Research Diagnostic Criteria and (2) global rating of psychiatric impairment using the Psychiatric Severity scale of the Addiction Severity Index (ASI). Follow-up interviews were completed 2.5 years after treatment seeking in 76% of a sample of 361 opiate addicts. Five dimensions of treatment outcome were assessed, including current functioning, psychosocial adjustment, substance use impairment, legal problems, and medical disability. Most lifetime psychiatric disorders with a prevalence of greater than 10% were significantly related to the outcome dimensions of current functioning and/or psychosocial adjustment and were unrelated to substance use impairment, legal problems, and medical disability. The ASI Psychiatric Severity rating more robustly predicted poorer functioning in the same two areas and less severe legal problems. While controlling for ASI Psychiatric Severity, the only Research Diagnostic Criteria diagnosis that remained significantly related to treatment outcome was major depression, suggesting that, as regards their prognostic characteristics, the other diagnoses are accounted for by a global underlying severity dimension.  相似文献   
89.
The content of cytochrome P-450 as a function of oxygen supply was studied during growth of Acinetobacter on n-hexadecane in batch cultures at constant pH and agitation. The rate of growth and the content of cytochrome P-450 were not affected as long as the dissolved oxygen tension ranged above 3 to 5% of saturation. The amount of cytochrome P-450 increased when the oxygen tension declined to zero. Cytochrome P-450 levels of about 0.3 to 0.4 nmol/mg protein, i.e. a more than a threefold increase, were observed under conditions where oxygen supply was strictly limited and allowed to maintain only a minimum of metabolism or growth. Limited oxygen supply exerted a special effect on the induction of the cytochrome P-450 as concluded from an increasing ratio between cytochrome P-450 and cytochrome o, and from the absence of cytochrome d in cells with elevated content of cytochrome P-450. The increased formation of cytochrome P-450 was a reversible process.  相似文献   
90.
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