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31.
Reed O. Elliott Jr. KellyLynne Hall Henry V. Soper 《Journal of autism and developmental disorders》1991,21(4):433-447
Examined the effects of two instructional methods on language generalization and longterm retention in 23 adults with autism and severe to profound mental retardation. Analog language teaching employed discrete trials in a controlled setting concentrating on discrimination and identification of materials. Natural language teaching emphasized instruction through interactions that occurred incidentally to training students in the use of materials to perform functional tasks. Assessments were conducted under conditions favoring analog teaching to assure against partiality toward natural language teaching. Under such disadvantageous conditions, the methods of natural language teaching would be supported by results showing either no difference or an advantage in their favor. Both techniques increased initial and long-term generalization though the results suggest no relative superiority for either method under these assessment conditions. A significant interaction was found between prior functioning level and sequence of instruction. Because natural language teaching has many strengths, few drawbacks, and produces equal generalization and retention under disadvantageous conditions, it is strongly supported as preferable for people with autism and mental retardation.The authors acknowledge the important assistance provided by the following people: the staff and management of the Behavior Development and Learning Center at CSH/DC directed by Israel Perel, Lisa Kramer, Steve Hafferkamp, James Lowdermilk, and, finally, and especially, to the participants themselves. 相似文献
32.
Twenty-four male right-handed adults performed a force production task with their right and left feet alone, and while sound-shadowing or listening to high frequency words. Overall, subjects performed better with their left foot than their right foot. Further, sound-shadowing, but not listening disrupted right foot performance. The concurrent language tasks had no effect on left foot performance. 相似文献
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The purpose of this study was to determine if cephaloridine nephrotoxicity is attenuated in streptozotocin (STZ)-induced diabetic rats. Fischer 344 (F344) rats (205-250 g) were given a single injection (i.p.) of STZ (27-35 mg/kg) or citrate buffer. The nephrotoxicity of (750 mg/kg) cephaloridine (i.p.) was then compared with normoglycemic and 14-day diabetic rats. Increased blood urea nitrogen (BUN) levels as well as diminished renal cortical slice accumulation of tetraethylammonium (TEA) and lactate-stimulated p-aminohippurate (PAH) were measured (P less than 0.05) in normoglycemic rats 48 h after cephaloridine administration. Cephaloridine failed to alter BUN levels and organic ion accumulation in diabetic rats. Diabetes did not totally protect against cephaloridine toxicity since kidney weights were elevated in normoglycemic and diabetic rats 48 h after administration of 750 mg/kg cephaloridine. A series of experiments also measured BUN levels, kidney weight and renal cortical slice uptake of PAH and TEA 24, 48 and 72 h after (1500 mg/kg) cephaloridine administration. Cephaloridine increased (P less than 0.05) kidney wt and decreased PAH and TEA uptake (P less than 0.05) in the normoglycemic group at 24-72 h. No change in kidney wt, PAH or TEA uptake was observed in the diabetic rats. These data indicate diabetes reduces cephaloridine nephrotoxicity. 相似文献
35.
L F Hiratzka C L Eastham J G Carter J R Moyers D R Elliott D B Doty C B Wright M L Marcus 《The Annals of thoracic surgery》1988,45(5):474-481
In normal coronary arteries, reactive hyperemic responses to a 20-second occlusion, an index of coronary reserve, usually demonstrate a peak-to-resting flow velocity ratio of 4:1 or more. Most intraoperative studies that have assessed reactive hyperemic responses in bypassed vessels have reported peak-to-resting flow velocity ratios of 2:1 or less following a 20-second occlusion. These decreased reactive hyperemic responses could be due to coronary vasodilatation after cardiopulmonary bypass or to an inadequate physiological result of the surgical procedure. In 14 patients with angiographically normal coronary arteries, the peak-to-resting flow velocity ratio following a 20-second coronary occlusion decreased significantly (p less than 0.05) from 4.4 +/- 0.2 (mean +/- standard error) before bypass to 3.0 +/- 0.3 after bypass. In a similar dog model, the peak-to-resting flow velocity ratio decreased by 36 to 52% during the first hour following one hour of cardiopulmonary bypass and cardioplegia. During the same period, left ventricular perfusion increased 21 to 30%, mean arterial pressure and coronary vascular resistance decreased, and myocardial oxygen consumption was unchanged. In a second group of dogs studied for the effects of duration (200 to 240 minutes) of anesthesia and thoracotomy alone, peak-to-resting flow velocity ratio was significantly lower. These clinical and experimental studies suggest that major coronary vasodilatation occurs early following cardiopulmonary bypass and cold cardioplegia, and may contribute to the blunted coronary reactive hyperemic responses reported during this time. Consequently, an intraoperative peak-to-resting flow velocity ratio of 3:1 for bypassed coronary arteries may represent an excellent physiological result. 相似文献
36.
C E Green M Glass-Royal P R Bream B Soto L P Elliott 《AJR. American journal of roentgenology》1988,151(3):455-459
The results of cinefluoroscopic evaluation in 509 patients in whom there was no evidence of prosthetic mitral or aortic valve regurgitation were compared with those in 41 patients who had perivalvular aortic or mitral regurgitation. Rotational motion of the base ring of each prosthesis (base-ring tilt) was measured in at least two views. A base-ring tilt of 7 degrees or more for aortic prostheses or 11 degrees or more for mitral prostheses was associated with an increased incidence of significant perivalvular regurgitation. Likewise, in patients who had multiple studies, a change between studies in base-ring tilt of 4 degrees or more for aortic prostheses or 5 degrees or more for mitral prostheses was associated with significant perivalvular regurgitation. These data suggest that the presence of either an abnormal base-ring tilt or an abnormal increase in base-ring tilt is strong, supportive evidence of partial prosthetic valve dehiscence. 相似文献
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38.
S Cole I J Stratford E M Fielden G E Adams W Leopold W Elliott M Suto J Sebolt-Leopold 《International journal of radiation oncology, biology, physics》1992,22(3):545-548
Following the toxicity and synthetic difficulties encountered with the hypoxic cell radiosensitizer RSU 1069, efforts have focused on development of a superior analogue. Two compounds, RB 6145 and PD 130908, have emerged from this program which overcome the instability and synthetic problems associated with RSU 1069 while retaining favorable biological activity. Both agents show comparable radiosensitizing activity to RSU 1069 following oral or i.p. administration to mice bearing the KHT or RIF-1 tumors. Sensitizing efficiency is about 10 X greater than that observed for misonidazole or etanidazole. Toxicity toward hypoxic tumor cells in vivo is demonstrated by clamping tumors (for 60 min) following administration of PD 130908 or RB 6145. Both are effective hypoxic cytotoxins, but less potent than RSU 1069. Systemic toxicity is substantially reduced following oral drug administration. Further, doses achievable following fractionated drug treatments are sufficiently high to produce significant levels of radiosensitization. 相似文献
39.
Mutated c-Ha-ras oncogene alters cytokeratin expression in the human breast epithelial cell line MCF-10A.
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T. M. Paine G. Fontanini F. Basolo I. Geronimo J. W. Elliott J. Russo 《The American journal of pathology》1992,140(6):1483-1488
MCF-10A, a spontaneously immortalized human breast epithelial cell line, has been transformed by transfection with the mutated c-Ha-ras oncogene obtained from T24 carcinoma cells. The pattern of cytokeratin expression was studied in MCF-10A cells in comparison with plasmid transfected or MCF-10Aneo cells, normal ras proto oncogene transfected or MCF-10AneoN cells, and transformed or MCF-10AneoT cells. Cytokeratin expression was studied by western immunoblot of total cellular proteins separated by two-dimensional gel electrophoresis. Blots with cytokeratin specific AE1 and AE3 antibodies showed identical molecular weight species of cytokeratins in MCF-10A, MCF-10Aneo, MCF-10AneoN, and MCF-10AneoT cells; however, in MCF-10AneoT cells, the intensity of immunostaining and the number of immunoreactive phosphorylated polypeptides keratins 7, 8, 15, and 16 was decreased. It was concluded that c-Ha-ras oncogene-induced transformation alters quantitatively the cytokeratin pattern of human breast epithelial cells and that these changes could explain some of the morphologic alterations observed in c-Ha-ras transformed cells. 相似文献
40.
To better understand adjustment following spinal cord injury (SCI), 106 subjects from two samples (N = 53 each) were administered the SCL-90-R, a symptom checklist, and the Multidimensional Health Locus of Control scales. Sample 1 subjects were admitted for rehabilitation during 1981 to 1982 and sample 2 subjects were admitted during 1984 to 1986. Sample 2 subjects entered rehabilitation programs more quickly after injury and reported more anxiety, phobic anxiety, and hostility than sample 1 subjects. Within each sample, there was no evidence for a relationship between age or time since injury and health beliefs or psychological distress. This study does not support stage theory for adjustment after catastrophic injury, but does suggest the importance of understanding the impact of social policy changes in adjustment following spinal cord injury. 相似文献