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41.
The extracellular electrophysiological properties of neurons in the laterodorsal tegmental nucleus (LDT), a major source of cholinergic afferents to the thalamus, were studied in chloral hydrate-anesthetized rats. A combination of antidromic activation from the thalamus and histological verification of recording sites was used to correlate the identity of extracellular recordings in the rat LDT with cholinergic neurons in that region. All neurons antidromically activated by stimulation of the anteroventral thalamus were histologically verified to be within clusters of cholinergic (NADPH-d-positive) cells in the LDT or in the adjacent nucleus locus coeruleus (LC). The thalamically projecting LDT neurons had a homogeneous neurophysiological profile consisting of long duration action potentials (mean = 2.5 ms), slow conduction velocities (mean = 0.78 m/s), and lengthy chronaxie values (mean = 0.725 ms). The appearance and axonal characteristics of these neurons resembled those of noradrenergic LC neurons, but the two populations exhibited substantially different spontaneous activity patterns and sensory responsiveness. These characteristics may be useful in the preliminary identification of putative cholinergic neurons in vivo, and thereby provide a foundation for exploring the neuropharmacology, afferent modulation, sensory responsiveness and behavioral correlates of the brainstem cholinergic system. 相似文献
42.
Nail plate and nail unit abnormalities may be helpful as diagnostic tools or as a part of the puzzle for confirmation of systemic disease. There are specific and nonspecific nail signs, which can be seen involving one or more nails, that occur simultaneously or secondary to systemic disease. Occasionally these clues can be diagnostic, while most are nonspecific reaction patterns. Nail changes occur in the nail plate as a result of nail matrix abnormalities caused by systemic disease and other systemic insults such as reactions to medications. In this article we review some of the more common nail signs that can be used to help diagnose systemic disease. 相似文献
43.
目的观察双线性带灌注的玻璃体切割器治疗外伤性白内障植入IOL的疗效.方法经巩膜隧道切口,彻底清除脱入前房的玻璃体及混杂在一起的晶体皮质,尽量保护好残留的晶体后囊膜、前囊膜,植入后房型人工晶体18例18眼.术后随访6个月.结果术后18例18眼的视力较术前均有明显提高,其中0.1以下为3眼,0.1~0.3为9眼,0.3~0.5为4眼,0.5~0.8为2眼,经配对t检验P<0.01,差异有显著性意义.视力恢复的情况与角膜穿通伤及眼后段的损伤程度密切相关.结论该手术具有安全性高、术后炎症反应轻、并发症少等优点,是治疗伴有其它眼部损伤的外伤性白内障的有效治疗方法. 相似文献
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46.
A model is described for obtaining long-term and stable discriminative conditioning-related slow-potential and single-unit responses from the frontal cortex of urethane-anesthetized rats. Responses were recorded and analyzed to reinforced (rewarding medial forebrain bundle stimulation) and non-reinforced tone cues. In the present study, cortical event-related slow potentials provided an adequate index of the level of discriminative conditioning. Single-unit response patterns are described for 57 neurons which demonstrated a discriminative response to either the reinforced or non-reinforced tone cue. 相似文献
47.
The H-reflex of 120 soleus motoneurons was recorded using fibre EMG. The recovery profile of these motoneurons was studied during monitoring surface H-reflex records in 28 adult subjects. The spectrum of motoneurons tested was homogeneous with two extremes of neurons having different characteristics. A motoneuron population (forming about 69% of our sample) had a high threshold level for electrical stimuli, short recovery time, and short recovery fringe time (called type A). A second population of motoneurons (forming about 20-30% of our sample) had a low threshold level for electrical stimuli, long recovery fringe time (called type B). During an isometric muscle contraction every motoneuron showed an early shift in recovery time (i.e. each had a shorter recovery time) with shortened recovery fringe time. These changes were larger for motoneurons type B than motoneurons type A. With paired identical electrical stimuli of varying interstimulus intervals a motoneuron may fire in response to the conditioning and test stimuli giving an H2, but not in response to both stimuli. This occurred for interstimulus intervals of 4-11 ms. A strong inhibition period was recorded with interstimulus intervals of 12-80 ms in which all motoneurons did not show any recovery. Most motoneurons recovered in orderly fashion between 80 and 300 ms of interstimulus interval, and this recovery coincided with the fast recovery recorded in surface H-reflex. All motoneurons were recovered by 3000 ms of interstimulus intervals. These findings emphasize the importance of eliciting the H-reflex every 3-5 s in H-reflex methodology in order to be assured that all excited motoneurons have been recovered. 相似文献
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49.
目的 了解2型糖尿病患者住院前及住院期间卒中各危险因素的干预状况,发现临床实践与证据之间的差距,提高临床医生对卒中一级预防的认识,指导今后的临床治疗。方法 本调查为横断面调查研究,回顾性调查167例2型糖尿病患者住院前及住院期间对卒中主要危险因素的干预情况。结果 被调查的患者中,入院前有46.7%的患者有高血压;36.0%的患者有吸烟史;19.8%的患者存在冠状动脉粥样硬化性心脏病,0.6%的患者有心房颤动;23.4%的患者有脂代谢异常。出院前有56.9%的患者被诊断高血压;81.4%的患者存在脂代谢异常。入院前与出院前对血压的药物干预率差异无统计学意义(分别为75.6%及80.0%,P >0.05);入院前后的降脂治疗(分别为25.6%及69.1%,P <0.01)及降糖治疗(分别为82.0%及97.6%,P <0.01)的差异均有统计学意义。结论 2型糖尿病患者院前对危险因素干预的达标率较低,应加强2型糖尿病患者及临床医生对卒中一级预防的认识,提高卒中卒中相关危险因素的干预率。 相似文献
50.
目的探索一种适合ICU护理工作特点的管理模式,提高管理效应。方法用护理工作量、ICU护理质量标准奖惩考核、职称系数三部分综合考评护理工时,与护士的绩效工资分配直接挂钩。结果护理工时量化法实施后,护理质量考核评分,患者?医生对护理质量满意率显著高于实施前(P〈0.05,P〈0.01)。结论护理工时量化绩效分配克服了经验式管理的弊端,建立了有效的激励机制,体现了多劳多得、优劳优得的分配原则,挖掘了护理人员的自身潜力,提高了护理质量。 相似文献