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951.
Traumatic aneurysms (TAs) are an unusual etiology for late neurological deterioration after traumatic brain injury (TBI) and represent less than 1% of all cerebral aneurysms. TAs most often are diagnosed acutely but may be delayed in presentation. To increase awareness of this serious but treatable condition when diagnosed early, we report a delayed TA after a motor vehicle accident. The patient experienced a seizure on day 46 postinjury while in rehabilitation and demonstrated persistent lethargy and hemiparesis. Neuroimaging revealed a large, ruptured left pericallosal artery TA, which was surgically clipped. The patient completed his rehabilitation course and was eventually discharged home with family. Among TBIs, TAs are associated with penetrating injuries and skull base or anterior cranial fossa fractures. Associated mortality is high, especially if rupture has occurred. Although TAs are rare, the clinician should be vigilant in the at-risk patient. 相似文献
952.
L De Salvo F Razzetta A Arezzo U Tassone G Bogliolo D Bruzzone F Mattioli 《Canadian Metallurgical Quarterly》1997,23(6):522-525
Early diagnosis of local and distant recurrences of colorectal cancer remains difficult and there is no agreement on the effectiveness of follow-up in these patients. The aim of this study is to assess the value of our method of follow-up. We consider 239 patients with colorectal cancer and at least 2 years follow-up following radical resection. A local recurrence appeared in 26 patients (10.9%), a distant metastasis in 41 (17.1%), while in seven (2.9%) local and distant recurrences appeared simultaneously. Local recurrence was detected because of an increase in carcinoembryonic antigen (CEA) level in 15 patients (57.7%), during a scheduled endoscopy in four (15.4%) and because of symptoms in seven (26.9%). In seven patients (26.9%) a radical resection was possible. Distant metastases were detected by CEA levels in 20 patients (48.8%), by ultrasonography (U.S.) in 12 (29.3%) and by chest X-ray in five (12.2%). In 13 of 26 patients with liver metastases a resection was performed. This study shows that few patients benefit from follow-up and only CEA levels and liver U.S. performed intensively between 15 and 36 months after surgery are useful in early detection of recurrences. A modification of the follow-up to the single patient, according to the stage, location and grading of cancer, could improve the results, so lowering the costs of this expensive practice. 相似文献
953.
A. Mclntyre 《Journal of Computer Assisted Learning》1993,9(4):262-267
Abstract This paper looks at some of the problems of existing courseware authoring systems, and advocates the use of knowledge-based techniques to resolve these problems and to form the basis of future authoring environments. The prototype knowledge-based representation language, GTE, is presented as an example of a knowledge-based language which might form the basis of such environments. The final part of the paper discusses some of the developments in GTE which must take place if it is to be used within a full and flexible authoring environment. The paper will focus particularly on the question of instructional strategies, but many of the observations can be taken as relevant to all the knowledge involved in a teaching interaction. 相似文献
954.
An improved accelerated cable life test is described. Through the use of programmable logic controllers (PLCs), very precise and consistent control of the accelerated aging process has been achieved. A computer has been utilized to make continuous real-time acquisition and storage of key operating parameters possible. This precise control and monitoring methodology has permitted the study of the synergistic effects of voltage and temperature on the accelerated aging of full-sized cables in the laboratory 相似文献
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Development of a new scale to measure patient behavior in group psychotherapy, the Individual Group Member Interpersonal Process Scale (IGIPS), is described. This scale captures clinically important aspects of how patients act in group, including how they respond to the other group members. The IGIPS was applied to videotapes of the first four sessions of seven 15-session outpatient therapy groups (52 patients) in the Mental Health Department of a health maintenance organization. The scale was found to have five factors (Activity, Interpersonal Sensitivity, Comfort with Self, Self-Focus, and Psychological Mindedness). Patient behavior that was moderate on two IGIPS dimensions was connected with better outcome than was that of patients with more extreme behavior in either direction. 相似文献
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