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941.
The article discusses a holistic approach to clinical scholarship by examining dimensions of scholarship and patterns of knowing. Innovative clinical teaching strategies in relation to these dimensions of scholarship and patterns of knowing are identified. Experiential learning, content mapping, and portable patient problem packs are explored. Knowledge building and creativity in the process of educating students are imperative. Nurse educators are challenged to develop new paradigms for nursing education that create a dynamic learning environment and result in enhanced clinical scholarship. 相似文献
942.
943.
JK House LW George KL Oslund FD Galey AW Stannard LM Koch 《Canadian Metallurgical Quarterly》1996,209(9):1604-1607
A herd of 650 Holstein cows was examined for skin disease. Approximately 400 of the lactating adults were affected, but heifers, calves, and nonlactating cows were clinically normal. The condition was characteristic of primary photosensitization. Milk production of the affected cows was normal. Affected cows did not appear to be ill, and none of the cows was icteric. Three of 7 cows had high serum gamma-glutamyltransferase activities, but in the other 4 cows, activity was within the reference range. Serum activities of other hepatic enzymes were within reference ranges in the 7 cows that were examined. Hepatic biopsy specimens from 3 cows were normal. Specimens from 4 other cows had changes that ranged from minimal to mild, chronic, lymphoplasmacytic periportal hepatitis to acute, random, necrotizing hepatitis. Development of photosensitivity was related to ingestion of alfalfa silage. Acetone extracts of the alfalfa silage, but not of other feedstuffs, were found to inhibit growth of Candida albicans under ultraviolet light. Cows experimentally fed a diet composed exclusively of the alfalfa silage developed skin lesions after 6 days, but did not have detectable serum concentrations of phylloerythrin. 相似文献
944.
945.
CT and MRI findings in three patients, two of them siblings, with microcephalia vera are presented. In this rare entity, a very small brain with an extremely thin, smooth cortex and increase surrounding cerebrospinal fluid are observed. 相似文献
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947.
948.
949.
SS Coughlin MC Tefft JC Rice JL Gerone KL Baughman 《Canadian Metallurgical Quarterly》1996,143(9):881-888
Although idiopathic dilated cardiomyopathy is often viewed as an affliction of young of middle-aged adults, morbidity and mortality rates from idiopathic dilated cardiomyopathy rise sharply with age and are the highest in the elderly. To learn more about the determinants of this increasingly important cause of heart failure in the elderly, the authors conducted a pooled analysis of data from two case-control studies of idiopathic dilated cardiomyopathy carried out in Baltimore, Maryland (1984-1986), and in Washington, DC (1990-1992). Identical diagnostic criteria and interviewing procedures had been used in both studies. All of the cases of idiopathic dilated cardiomyopathy had evidence of ventricular dilation and hypokinesis, with a left ventricular ejection fraction of < 40%. Cases with a history of coronary artery disease were excluded along with those with known secondary forms of cardiomyopathy, Up to two neighborhood controls of the same sex and appropriate age (+/- 5 years) were selected for each case using a random digit dialing technique. The subjects or a suitable surrogate was interviewed by telephone to obtain medical history information. The present analysis was limited to 94 cases and 152 matched controls who were at least 60 years of age. Conditional logistic regression methods were used in the analysis. Significant associations were observed with lower educational attainment and a history of hypertension (P < 0.05). The association with hypertension (relative odds = 2.2, 95% confidence interval 1.1-4.6) persisted after adjustment for race, education, and diabetes and was not accounted for by coronary angiography utilization patterns. The association with diabetes was of borderline significance (p < 0.10). The pattern of risk factors identified in this analysis may allow for the early identification of elderly persons who are at increased risk of idiopathic dilated cardiomyopathy. 相似文献
950.
Local delivery of pharmacologic or genetic agents with a porous balloon catheter offers a potential therapeutic approach to reducing restenosis and atherosclerosis and minimizing undesirable systemic toxicity. However, the delivery efficiency and intramural retention of liquid agents is low. The local intramural delivery and prolonged retention of 5 microns microparticles (MP) has been described previously. The current study was designed to evaluate the distribution of locally delivered MPs and to determine the effects of MP size and infusion pressure on intramural delivery efficiency. A 1% suspension of fluorescent, latex MPs (1 or 4.5 microns in diameter) was infused at either 3 or 6 atm into atherosclerotic rabbit femoral arteries (n = 32) immediately after angioplasty. Four groups of arteries were evaluated: 1) 1 micron MPs infused at 3 atm; 2) 1 micron MPs at 6 atm; 3) 4.5 microns MPs at 3 atm; and 4) 4.5 microns MP at 6 atm. The location of MPs was evaluated by fluorescent and light microscopy and confocal laser scanning microscopy. The tissue was dissolved and the delivered MPs quantified. All groups manifested numerous MPs within the vasa vasorum and periadventitial microvasculature, with a substantially lesser number within the neointimal and medial layers. The intramural deposition of the MPs was associated with dissection within the intima or media caused by the antecedent angioplasty or local delivery, indicating that an intact vessel wall is an anatomic barrier to MP delivery. The median values of fractional intramural delivery, defined as the percentage of infused MPs retained within the arterial wall, were 0.059%, 0.071%, 0.047%, and 0.062% for the groups 1 through 4, respectively (p not significant [NS]). The values of intramural particle concentration, expressed as the total number of MPs per weight of arterial tissue, were 55, 65, 1.5, and 1.2 x 10(4) MPs/mg for groups 1 through 4, respectively (p < 0.001 for 1 micron vs 4.5 microns MPs). Although more 1 microM MPs were delivered than 4.5 microns MPs, the fractional intramural delivery was unaffected by particle size or infusion pressure. The local delivery of MPs at atherosclerotic sites after angioplasty is characterized by fractional intramural delivery values similar to values of nonparticulate agents, with few MPs deposited into intima or media in the absence of a dissection caused by the antecedent angioplasty or the delivery procedure itself. 相似文献