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51.
P. V. PEPLOW 《Medical education》1990,24(5):426-432
This paper reports an attempt to develop self-directed learning skills in second-year medical students by introducing case-based projects into the gross anatomy course at a long-established medical school. The programme and students' responses to a questionnaire completed at the end of the year are presented. Information on the various resources used by students to find information is given. The performance of students in the case-based components of the course has been evaluated and also in the more traditional end-of-year written examination. The data confirm that students have recognized that the projects were about obtaining a deeper understanding of the anatomy, and the programme appears to have promoted the use and study of library texts. 相似文献
52.
Sheryl A. Scott Seth Dinowitz Kristen Terhaar Diane Sherlock Maurice A. Campbell Dreania Levine 《The Journal of comparative neurology》1994,350(2):302-310
The goal of the present study was to identify cytochemical markers characteristic of muscle afferents in hatchling chicks. To this end, we stained neurons in the trigeminal mesencephalic nucleus with a variety of markers that label subsets of neurons in avian dorsal root ganglia. We found that trigeminal mesencephalic neurons are surprisingly heterogeneous in their cytochemical make-up, expressing, to varying degrees, substance P, cholecystokinin, carbonic anhydrase, calbindin D-28k, parvalbumin, and S-100β. Calbindin D28k and S-100β appeared to be expressed equally in medial and lateral divisions of the trigeminal mesencephalic nucleus. In contrast, substance P- and cholecystokinin-immunoreactive neurons were more abundant in the medial division, whereas carbonic anhydrase activity and parvalbumin immunoreactivity were stronger in the lateral division. We were unable to detect met-enkephalin, neuropeptide Y, calcitonin gene-related peptide, vasoactive intestinal peptide, somatostatin, γ-aminobutyric acid, or tyrosine hydroxylase in the trigeminal mesencephalic nucleus. Moreover, these neurons did not appear to bind the lectin Dolichos biflorus agglutinin. The heterogeneity of expression of markers among trigeminal mesencephalic nucleus neurons, especially between neurons in the medial and lateral divisions, suggests that these neurons are functionally diverse. 相似文献
53.
本实验采用单细胞外记录神经元单位放电的方法,在Wistar大鼠上观察到网状巨细胞核。一区伤害性神经元57个,其中伤害兴奋性神经元(NEN)42个,伤害抑制性神经元(NIN)15个。电刺激黑质对NEN(29)和NIN(8的放电呈抑制作用,其反应百分率分别由刺激黑质第1分钟时的1.0±2.1%和-20.4±6.2%,降到第5分钟时的-83.6±12.3%和-65.4±10.7%(P<0.01)。刺激黑质对少数NEN(13)和NIN(7)的放电有兴奋作用,其值分别由第]分钟时的20.5±7.3%和1.0±3.4%,升高到第5分钟时的74.5±10.7%和21,5±8.6%(P<0.05)。氟哌啶醇注入PAG腹外侧部可阻断刺激黑质的效应,这提示从黑质到网状巨细胞核α-区存在着一条痛调制通路,而且这种通路的递质是多巴胺能的。 相似文献
54.
Clinical Evaluation of a New Type of Centrifugal Pump 总被引:2,自引:0,他引:2
J. Ninomiya T. Shoji S. Tanaka M. Ikeshita M. Ochi S. Yamauchi T. Yajima H. Yamauchi T. Sugimotox T. Aizawa 《Artificial organs》1994,18(9):702-705
Abstract: The major problems with existing centrifugal pumps are leakage, mechanical trauma, and thrombus formation. In consideration of these problems, a new compact centrifugal pump system was developed. The purpose of this study was to evaluate the new centrifugal pump system clinically. Ten patients underwent open heart surgery with a centrifugal pump or a roller pump. During surgery, hemodynamic and hematological data were obtained. A pulsatile assist device in the pump circuit was used in patients with severe heart disease. There was neither operative death nor hospital mortality, and there was no difference with regard to hemodynamic data between the two groups. The centrifugal pump group, however, had significantly lower hemolysis, especially during prolonged cardiopulmonary bypass. This centrifugal pump could also create sufficient pulsatile flow with a pulsatile assist device. Postoperative macroscopic and microscopic findings demonstrated the smooth surface of the pump without thrombus formation. This centrifugal pump system might be useful for prolonged cardiopulmonary bypass. 相似文献
55.
Sherif M. Hassan Frans G.I. Jennekens George Wieneke Henk Veldman 《Neuromuscular disorders : NMD》1994,4(5-6):489-496
Changes in calcitonin gene-related peptide-like immunoreactivity (CGRP-LI) at the motor endplates of botulinum toxin-paralysed rat muscles were investigated using immunohistochemistry. One day following toxin injection, a dramatic increase in CGRP-LI was detected at the motor endplates and within preterminal axons of the soleus and gastrocnemius muscles. The upregulation of CGRP-LI persisted throughout the period during which muscle fibres were paralysed and new neuromuscular junctions were being formed by the growing sprouts. Decline of CGRP-LI at the motor endplates coincided with clinical recovery. Both up- and down-regulation of CGRP-LI took place earlier in the soleus than in the gastrocnemius muscle. Up-regulation of CGRP-LI was also detected in a subpopulation of motor axons in the sciatic nerves and in the spinal motor neurons innervating the paralysed muscles. These results indicate that levels of CGRP are regulated, at least partly, by changes in the target innervation. They also suggest an important role for CGRP in the regenerative processes following muscle paralysis. 相似文献
56.
将胚鼠中脑腹侧组织制成细胞悬液移植于帕金森病(PD)模型鼠侧脑室,动态观察受体鼠在移植前后的行为变化。移植后16周应用诱发荧光及免疫细胞化学等方法,对移植物在受体鼠脑内的存活及生长情况进行了研究。结果,受体鼠旋转行为明显改善,侧脑室内可见黄绿色荧光细胞及酪氨酸羟化酶(TH)免疫反应阳性细胞,有的发出突起伸向室管膜及迁于尾核区.提示:移植的胚鼠黑质细胞生长良好,似作为触液神经元发挥其作用。 相似文献
57.
成孔素和颗粒酶在体内的表达──活化杀伤细胞的有效诊断标志陈永良译余传霖校(郧阳医学院免疫学教研室十堰442000)细胞毒淋巴细胞(CTL)胞内特殊颗粒中含有一组专一性的具有细胞毒活性的蛋白质,这些颗粒和完整的杀伤性细胞一样能够溶解靶细胞.可能还有其它... 相似文献
58.
试论新世纪初期医院综合院力评价 总被引:30,自引:17,他引:13
作者阐述了医院综合院力的内涵与提出背景,提出了新世纪初期综合院力的评价内容体系,即一级评价内容7项,二级评价内容39项,三级评价内容15l项,并就各指标评价内容进行了讨论分析。 相似文献
59.
目的 观察异丙酚对 1 甲基 4 苯基 1,2 ,3 ,6 四氢吡啶 (1 methyl 4 phenyl 1,2 ,3 ,6 tetrahydropyridineMPTP)损伤的小鼠纹状体多巴胺神经元的影响以及可能的作用机制。方法 给予Propofol 10 0mg/ (kg·d)后注射MPTP 2 0mg/ (kg·d) ,用药 6d。 12d后分离纹状体应用高效液相 -电化学方法检测纹状体多巴胺、二羟基苯乙酸及高香草酸的含量水平 ,应用12 5I- β-CIT放射性配基和免疫组化的方法检测多巴胺转运蛋白的活性和黑质神经元的损伤情况。结果 异丙酚可增加MPTP模型鼠多巴胺及其代谢产物的含量 ,异丙酚处理组DA ,DOPAC ,HVA的含量分别为 (8.2 417± 1.692 ) μg/ g、(1.3 81± 0 .486) μg/g和 (1.63 3 9± 0 .5 73 ) μg/ g ,与MPTP损伤组比较 ,明显增加。异丙酚亦可抑制黑质酪氨酸羟化酶 (TH)阳性神经元的减少。MPTP组注射MPTP 6d后 ,纹状体DAT为 (5 .3 13± 0 .64 2 )与正常组 (6.992± 0 .5 48) μg/ g比较显著下降 (P <0 .0 1) ,P +M组纹状体DAT为 (6.5 65± 0 .40 5 ) ,明显高于MPTP组 (P <0 .0 1) ,即减轻纹状体内多巴胺转运蛋白密度下降。结论 异丙酚对MPTP损伤的DA神经元具有一定的保护作用 ,其保护作用可能与抑制多巴胺转运蛋白活性有关 相似文献
60.
2002~2006年广西大专新生乙肝病毒携带率观察 总被引:1,自引:0,他引:1
[目的]观察2002~2006年广西大专新生乙肝病毒携带率分布,为进一步防治乙型肝炎提供理论依据。[方法]收集2002~2006年大专新生入学体检资料,采用SPSS13.0软件进行整理、统计分析。[结果]2002~2006年5年中广西大专新生HBV携带率呈明显下降的趋势,平均每年以10%的速度下降,2006年乙肝病毒携带率比2002年下降了44%,尤其以2005年桂东南汉、壮民族下降最为显著。[结论]80年代中期广西普遍接种乙肝疫苗以后,乙肝疫苗阻断乙型病毒性肝炎在广西青少年母婴传播及水平传播效果已经显现。建议在广西各地区,尤其是在桂西北少数民族地区进一步加强乙型肝炎基因工程疫苗的接种工作力度,使乙型病毒性肝炎感染率控制到更低的水平。 相似文献