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991.
992.
Technical Physics Letters - GaAs Schottky barrier detectors for α particle spectrometry have been tested. Detectors had an input window area of 80 mm2 and a working barrier layer thickness of...  相似文献   
993.
994.
With the increasing emphasis on independent learning and early patient contact, the time in the undergraduate medical curriculum for formal teaching of morphology of disease is decreasing. Thus, we thought it advisable to identify those core morphological entities of disease that should not get lost in the new paradigm. Our approach was to list all disease processes in Robbins Pathologic Basis of Diseases, 5th edition, that have distinguishing gross or microscopic characteristics. Appropriate portions of this list of 952 morphological entities from the Robbins textbook were distributed to 46 clinical specialists and pathology faculty. Each of these was asked to strongly agree, agree, disagree, or strongly disagree with the following for each entry on the list: "For purposes of developing concepts of disease, an M2 physician in training should recognize classical examples or a diagrammatic representation of the following lesions, and distinguish them from each other." Responses resulted in a consensus core list of 63 general disease process lesions and 545 organ system lesions, for a total of 608. These 608 core morphological entities were incorporated into our course by means of (1) a computer program with over 1,022 images and clinical-pathological correlations, and (2) a core list of morphological objectives for each unit in the course. In general, entities were judged noncore material if they were rare or were microscopic lesions of primary interest to pathologists and provided no major pathomorphologic concepts. The computer program as a supplement to glass slides and gross specimens has been very well accepted by students, and satisfactory performance on examinations has been maintained in spite of a 25% reduction in pathology course contact hours.  相似文献   
995.
To date, the "warm-up" phenomenon in patients has been evaluated by ECG and symptom analysis. We investigated the warm-up phenomenon with supine bicycle stress echocardiography in patients with coronary artery disease documented by angiography and positive stress echocardiography. Sixteen coronary artery disease patients (54 +/- 9 years), who were off treatment throughout the study, were enrolled. Each of them underwent two consecutive exercise tests (25 W/2 min) with a 10-min recovery to reestablish baseline conditions. At the end of each stage of exercise and at peak exercise, when wall motion abnormalities (WMA), 1 mm ST depression and angina occurred, and at each minute, for the first 6 min of recovery, a 12-lead ECG was recorded and rate-pressure product was calculated. Time of onset and duration of 1 mm ST depression, WMA and angina, were also determined. Peak WMA, peak wall motion score index, duration of exercise and severity of angina were also evaluated. Exercise time duration and peak rate-pressure product were greater during the second than the first test (p = 0.02, p = 0.03 respectively); the second test also showed a longer delay of the onset of 1 mm ST depression and WMA (p = 0.01, p = 0.01 respectively) and higher rate--pressure product values (p = 0.04, p = 0.03 respectively). On the contrary, wall motion score index during the first and the second test was similar. Time to angina onset was longer during the second test (p = 0.03); the recovery period of ST depression and WMA was shorter during the second test (p = 0.02). In conclusion, these preliminary data show that patients tolerated the second period of ischemia better than the first, consistent with the presence of the warm-up phenomenon. However, the similarity of values of wall motion score index and WMA did not support a reduction in the ischemic area during the second test. This is in contrast with a possible modification of myocardial metabolism which typically underlies the ischemic preconditioning.  相似文献   
996.
A 38-year-old woman was transmitted to hospital with profuse vaginal bleeding. The origin of the vaginal injuries (resulting from "normal" sexual intercourse vs. use of instruments for manipulation in the vagina) was obscure. The wound pattern is presented and the literature on the subject is reviewed with special reference to predisposing factors and genesis of coital injuries. Concerning the wound pattern, reflecting a blunt trauma, a manipulation with a (so far unknown) instrument, but also with finger or hand could not be proved with the required certainty. In the presented case the origin of the vaginal injuries from "normal" sexual intercourse as described by the accused man could not be excluded.  相似文献   
997.
To make health care more responsive to patient needs, insight into patient priorities is needed. A systematic literature review, using electronic and manual searches, was made of studies on patient priorities with regard to primary health care. Data-extraction was performed by two researchers, followed by systematic analyses of study features. 57 studies were included. The aspects of care and methods used showed a wide variation. Aspects most often included were "informativeness", "humaneness" and "competence/accuracy". Based on an analysis of 19 studies, the following aspects were seen by patients as most important in more than 50% of the studies that included them: "humaneness", "competence/accuracy", "patients' involvement in decisions", "time for care", "other aspects of availability/accessibility", "informativeness", "exploring patients' needs", "other aspects of relation and communication" and "availability of special services".  相似文献   
998.
999.
Instead of seeing technology as outside ourselves, it is argued that it is an innate human function and the main driving force in human evolution. Opportunistic thing using, long before stone tools appeared, was the likeliest cause of bipedalism. It also forced brain development and the emergence of creativity. The neural basis for this creative technical activity later provided the brain functions on which language could develop. This simple unifying hypothesis has interesting implications for the way that we see technology in history, and for determinist theories of the future. It also bears on the way engineers are trained, and more important, the human faculties which need to be fostered in children.  相似文献   
1000.
BACKGROUND: Improvement in vision with spinal manipulation was first observed in the early 1970s. Reports of the phenomenon appeared in the 1980s in the popular press and at scientific meetings, but it was not until the mid-1990s that general discussion of the potential value of this knowledge occurred. Considering the far-reaching implications of the possible ability to improve brain function by spinal manipulation, the delay in consideration and implementation of this concept is a paradox in general terms and a total mystery in the case of the chiropractic profession. OBJECTIVE: To provide explanations for the delay in scientific assessment of the discovery that vision improves, in appropriate patients, when the spine is manipulated and to discuss the implications of this finding. This discovery is now called the "tunnel vision information." DISCUSSION: A schema of pathological hierarchy is depicted in which the level of intervention of spinal manipulation outranks other forms of treatment. The significance of this precedence is portrayed. Possible reasons for the failure to address this hierarchy in light of the tunnel vision information are discussed with reference to established protocols, medical politics, the presentation of the data, the failure of scientific editorship and the illogical aspects of the illness itself. CONCLUSION: In the future, the delay from the initial observation of the tunnel vision discovery to its free discussion in scientific literature may seem incongruous, particularly if the health benefits which it augurs are realized.  相似文献   
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