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991.
This paper provides for the first time evidence of a consistent difference in the memory structures of novice and expert clinicians. The diagnostic performance of first- and third-year clinical medical students, senior house officers, registrars and consultants on four clinical problems in general medicine was studied. Comparisons were made of all diagnostic interpretations offered and the forceful features (personally important pieces of information which act as a key to particular memory structures which in turn give rise to the clinical interpretation) from which these were derived. Results demonstrate that the numbers of interpretations made and the numbers of forceful features identified did not differ significantly between groups (P greater than 0.05). However, the actual interpretations made in three out of four cases, and the actual forceful features identified in all cases, did differ significantly between groups (P less than 0.05). The numbers of interpretations made by all groups were large and demonstrated enormous variability. Highly individualized multiple responses to clinical information are associated with easy diagnoses. We conclude that there is no difference between groups of differing clinical experience in the breadth of thought but that there are marked differences in the precise content and structure of thought. This allows coherent explanation of variation in diagnostic expertise with clinical experience. The significance of the findings is discussed. 相似文献
992.
993.
Comparison of the haemodynamic effects of intermittent positive pressure ventilation with high frequency jet ventilation 总被引:1,自引:0,他引:1
The cardiorespiratory effects of intermittent positive pressure ventilation and high frequency jet ventilation with and without positive end expiratory pressure were compared in patients following valvular heart surgery (mitral and/or aortic). Twenty patients received intermittent positive pressure ventilation and high frequency jet ventilation with 0, 0.5 and 1.0 kPa positive end expiratory pressure. High frequency jet ventilation was well tolerated. The addition of 1.0 kPa positive end expiratory pressure was associated with preservation of the arterial oxygen tension without any increase in shunt or significant adverse haemodynamic effect. The results are discussed and compared with a previous study of high frequency jet ventilation following aortocoronary bypass graft surgery. 相似文献
994.
本文报告用~3H-TdR掺入法测定本室的NC系正常裸小鼠和荷人脑胶质瘤裸小鼠(NHG-1)的脾淋巴细胞转化功能。结果提示:正常的纯合子(nu/nu)T细胞缺乏,B细胞功能均正常;杂合子(nu/ )的T和B细胞功能均正常;荷瘤鼠(NHG-1,30代)除了T细胞缺乏,B细胞功能亦受到抑制。 相似文献
995.
张震宇 《天津中医药大学学报》2002,21(4):45-45
1 临床资料 本组62例中,男38例,女24例;年龄最大67岁,最小21岁,平均36岁;病程最长8 a,最短2个月,平均15个月.全部病例均有眩晕症状,常在颈部旋转或屈伸时出现或加重,伴颈枕部不适或疼痛,颈肌僵硬.伴耳鸣32例,伴恶心或呕吐23例,伴上肢麻木感15例. 相似文献
996.
997.
医学生营养知识与膳食状况调查 总被引:7,自引:1,他引:6
①目的了解医学生营养知识的掌握情况及对教育传播方式的需求意见,以加强营养知识教育,改善大学生的健康素质。②方法对762名在校大学生进行问卷调查。③结果医学院在校生对营养知识及常识掌握深度和广度都不够,但渴求得到营养知识的欲望比较高,对营养知识的重要性认识正确。有73.6%的学生认为营养知识对生活很重要。87.2%的学生愿意接受营养知识的教育,对营养知识教育的传播方式也表现出特有的需求意向。大学生的膳食结构不够合理,奶类、薯类、鱼虾禽类、豆制品摄入不足。④结论应加强医学生营养知识教育,使医学生做到科学合理的安排膳食,改善饮食行为,促进身体健康。 相似文献
998.
从中间体(4)出发,经醛(5),与鏻叶立德(3)或2-酮-4-苯丁烷磷酸酯(11)钠缩合成(6),再钠硼氢还原得3′α-醇(7A)及其差向异构体(7B),经硅胶柱色谱分开,分别经二异丁基铝氢还原,与溴化5-三苯鏻戊酸之Wittig试剂缩合,得17-苯-18,19,20-失三碳前列腺素F2α(9A)及其15-差向异构体(9B),再用重氮甲烷甲酯化,分别得相应的17-苯-18,19,20-失三碳前列腺素F2α甲酯(10A)及其15-差向异构体(10B)。 相似文献
999.
Comparison of computer-assisted learning with tutorial teaching in a group of first-year dental students 总被引:1,自引:0,他引:1
Two identical groups of first-year dental students were instructed in the pathology of dental caries and periodontitis using computer-assisted learning (CAL) or tutorial teaching (TT). A cross-over arrangement, in which the first group was taught about dental caries by CAL and periodontitis by TT and the second group in the reverse order, allowed comparison of the two methods. The comparison included a knowledge test and completion of a questionnaire. CAL and TT were equally effective as far as acquisition of knowledge was concerned. Students felt pressurized with CAL and had problems with note-taking. They liked a teacher to be present. Nevertheless, CAL was an acceptable method of instruction and was more economical, in terms of staff involvement, than TT. 相似文献
1000.
用改良的四氮唑硝基蓝(NBT)还原法观察了电针以及生物活性物质(BAS)包括5-羟色胺(5-HT)、血管活性肠肽(VIP)、生长抑素(SOM)和P物质(SP)对大鼠多形核白细胞(PMN)杀菌功能的影响。结果表明:电针及BAS均能增强大鼠PMN的杀菌功能(P<0.01);BAS对大鼠PMN的杀菌功能具有双向调节效应。纳洛酮可阻抑电针对PMN杀菌功能的提高(P>0.05);可被BAS所翻转。电针的镇痛效应和NBT阳性细胞提高效应之间存在着明显的正相关(P<0.01)。 相似文献