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221.
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Repetition of single words and pronounceable nonwords (pseudowords) was assessed in Alzheimer's Disease (AD) patients to evaluate how lexical phonological processing might be accomplished when semantic and conceptual knowledge is impaired. AD patients performed significantly worse than healthy elderly controls on all repetition tasks. However, repetition abilities and dementia severity were not correlated, and AD patients produced the same distribution of error types as controls. Furthermore, despite their semantic problems, AD patients, like controls, showed a significant advantage for repeating real words compared to pseudowords, even when repeating low frequency phonologically complex words whose meaning is not likely to have been retained. The results support the postulated existence of a lexical phonological system that is used to repeat both known and novel words and that processes linguistic information independent of its meaning. 相似文献
223.
Weedn V.W. McDonald M.D. Locke S.E. Schreiber M. Friedman R.H. Newell R.G. Temoshok L.R. 《IEEE engineering in medicine and biology magazine》2004,23(1):162-170
To date, biological weapons have proven to be more of a psychological threat than a physical danger, and while they may someday result in significant mortality they would seem always to create larger numbers of psychological illness. At least in the United States, they have proven to be weapons not of mass destruction but of mass psychogenic illness. 相似文献
224.
WA Breeman M de Jong BF Bernard WH Bakker EJ Rolleman DJ Kwekkeboom TJ Visser EP Krenning 《Canadian Metallurgical Quarterly》1997,24(8):749-753
In patients undergoing somatostatin receptor scintigraphy, treatment with octreotide (Sandostatin) is usually discontinued 24-48 h before and after injection with the radioligand 111In-pentetreotide ([111In-DTPA(O)]octreotide) (Octreoscan) because octreotide competes with radioligand for the same receptors. However, D?rr et al. and Soresi et al. reported improved visualization of carcinoid and small cell lung cancer lesions, respectively, during continued octreotide treatment. We found that intravenous administration of unlabeled octreotide to rats inhibited the binding of an optimal dose (0.5 microg) of 111In-pentetreotide to somatostatin receptors in pancreas and adrenals in a mass- and time-dependent way. Pretreatment with unlabeled octreotide never increased receptor binding of 111In-pentetreotide. Administration of 100 microg of octreotide decreased receptor-bound radioactivity if given simultaneously with or 10 or 20 min after injection of the radioligand, but had no effect if given 30 min after the radioligand. These findings indicate rapid processing of receptor-bound octreotide and suggest that octreotide treatment of patients undergoing 111In-pentetreotide scintigraphy may be reinitiated as soon as 1 h after radioligand administration. 相似文献
225.
Two men, aged 71 and 56 years, with pacemakers, developed the superior vena cava syndrome one and five years, respectively, after infection of the pacemaker pocket. They had been treated with antibiotics and partial removal of the foreign bodies. The conditions of both included occlusion of the superior vena cava and of both subclavian veins. The symptoms disappeared after removal of the total pacemaker system and venous reconstruction. The possibility of a superior vena cava syndrome occurring is increased if other complications have occurred previously, particularly infection. Prevention and treatment comprise on the one hand prevention and treatment of the infection (which is not always obvious) and on the other, earliest possible detection of thromboembolisms. 相似文献
226.
This article describes a new computerized local anesthetic injection system for pain control. The core technology of this system is the microprocessor-controlled delivery of anesthetic solution at a constant pressure and controlled volume, regardless of encountered variations in tissue resistance. This fine-tuned, high suffusion flow rate of anesthetic provides a rapid onset of anesthesia for most patients. Traditional block injections and infiltrations as well as palatal injections and periodontal ligament injections are administered with precision, ease, and patient comfort. 相似文献
227.
R Hachamovitch DS Berman H Kiat I Cohen H Lewin A Amanullah X Kang J Friedman GA Diamond 《Canadian Metallurgical Quarterly》1997,80(4):426-433
We examined 1,159 consecutive patients who underwent adenosine stress dual isotope single-photon emission computed tomography (SPECT) and had follow-up performed at a mean of 27.5 +/- 9.1 months (94% complete) for hard events (cardiac death and myocardial infarction) and referral to cardiac catheterization after nuclear testing. During follow-up, 120 hard events occurred (11.0% hard event rate; 72 cardiac deaths [6.7% cardiac death rate] and 57 myocardial infarctions [5.3% myocardial infarction rate]). Cox proportional hazards analysis revealed that nuclear testing added incremental value after adjusting for clinical and historical variables (global chi-square increased 13 to 98 for cardiac death as the end point, global chi-square increased 19 to 105 for hard events as the end point; p <0.0001 for both). Kaplan-Meier analysis demonstrated that after clinical risk stratification of the patient population, the results of nuclear testing were further able to significantly stratify both low- and intermediate- to high-risk patients. Patients with both normal and mildly abnormal scans were at low risk of cardiac death (<1% cardiac death per year of follow-up) and the risk of events increased significantly with worsening scan result. Multivariable analysis revealed that the only predictor of referral to catheterization was the extent and severity of reversible defect present on the scan. Referral rates to early catheterization were very low in patients with normal scans and increased significantly as a function of worsening scan results. In patients who underwent myocardial perfusion SPECT using adenosine stress, the results of nuclear testing yielded incremental prognostic information and clinically relevant risk stratification. Referring physicians predominantly utilized nuclear information when referring patients to catheterization after nuclear testing and do so at rates comparable with those after exercise SPECT despite the higher risk of events in patients undergoing pharmacologic stress. 相似文献
228.
Eby G. Friedman J. H. Mulligan Jr 《Analog Integrated Circuits and Signal Processing》1997,14(1-2):53-58
Closed form expressions are presented to accuratelydescribe the delay characteristics of RC tree networks.The Penfield-Rubinstein-Horowitz approach to estimating the stepfunction response of RC trees has been extendedto consider ramp inputs. This result improves timing accuracyby considering the shape of the input waveform driving each individualinterconnect tree while maintaining computational simplicityfor use in the automated timing analysis of complex VLSI circuits. 相似文献
229.
230.
Microalbuminuria is defined as urinary excretion of albumin that is persistently above normal, although below the sensitivity of conventional semiquantative test strips. Several studies have reported that Type 1 diabetic patients with microalbuminuria are apparently more likely to develop diabetic nephropathy eventually progressing to renal failure. Microalbuminuria is also a strong predictor of mortality in Type 2 diabetes, and is correlated with increased blood pressure in patients with benign essential hypertension. Radioimmunoassay revealed a significantly higher urinary albumin excretion rate in normal pregnant women in the third trimester of pregnancy, compared to the second and first, and compared to non-pregnant women. Microalbuminuria was found in 30% of women who had a record of gestational diabetes mellitus. Published results are controversial regarding the assumption that microalbuminuria is an early predictor of pregnancy-induced hypertensive complications. 相似文献