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1.
痛情绪是指因疼痛引发的情绪和情感体验,是疾病过程中最常见的一种情绪。痛情绪相关神经机制非常复杂,但主要与单胺类神经递质、神经肽和某些神经环路有关,笔者将结合目前研究现状分别从以上两方面展开,就痛情绪相关单胺类神经递质和神经肽在受体分类、脑区通路、共疾病以及各神经递质之间的联系和痛情绪相关神经环路中各个蛋白的作用机制等方面进行探讨。  相似文献   
2.
Deep brain stimulation (DBS) in psychiatric illnesses has been clinically tested over the past 20 years. The clinical application of DBS to the superolateral branch of the medial forebrain bundle in treatment‐resistant depressed patients—one of several targets under investigation—has shown to be promising in a number of uncontrolled open label trials. However, there are remain numerous questions that need to be investigated to understand and optimize the clinical use of DBS in depression, including, for example, the relationship between the symptoms, the biological substrates/projections and the stimulation itself. In the context of precision and customized medicine, the current paper focuses on clinical and experimental research of medial forebrain bundle DBS in depression or in animal models of depression, demonstrating how clinical and scientific progress can work in tandem to test the therapeutic value and investigate the mechanisms of this experimental treatment. As one of the hypotheses is that depression engenders changes in the reward and motivational networks, the review looks at how stimulation of the medial forebrain bundle impacts the dopaminergic system.  相似文献   
3.
静脉输液滴速自动显示仪的研制   总被引:3,自引:3,他引:0  
本文介绍了该产品基于数字电路和基于单片机ATMEL89C2051两种方案软硬件设计。能够正确显示静脉输液滴数,方便患者和减轻陪护人员的负担,并且在无药液和血管堵塞两种情况下,自动报警。在输液过程中,发光二极管同步显示液滴滴速快慢的变化。  相似文献   
4.
刘春旺 《医疗设备信息》2004,19(8):27-27,51
简述AGFA2050/S多幅相机工作原理,并就工作过程详细阐述,最后简单介绍控制电路。  相似文献   
5.
The Low Vision Clinic at the Palmerston North Hospital has now been oerating for 70 years. Over the course of these ten years a number of factors have emerged which can be as readily applied to general ophthalmological practice as to low vision practice. The philosophy of low vision care is one of which all ophthalmologists should be aware and includes factors to be taken into account when dealing with children, people in the workplace, and everyday factors involved in daily living activities, all of which are equally relevant in routine ophthalmological practice. This paper endeavours to share some thoughts on these factors and also discusses means by which the visually handicapped can be helped in areas where specialist low vision services are not readily available.  相似文献   
6.
Stress is a general reaction to any burden on the body. If such a process becomes chronic, stress-based diseases develop which are hard to treat. The stress cycle in the hypothalamus-hypophysis-suprarenal glands disturbs the bio-psycho-social circuit, which is in a feedback loop with controlled and uncontrolled stress converting processes. This is coupled with the reactivity of the extracellular matrix (ECM) embedded in this circuit. Two “breaks” are installed in the ECM to keep stress reactions under control: The non neuronal acetylcholin system (NNAChS) and the system of endogenous endocannabinoids. Both systems have a limiting effect on pathological increased sympathetic effects raised by stress. Acupuncture stimulates the parasympathicus and NNAChS while neural therapy augments the endocannabinoid system, resulting in slower sympathetic actions.  相似文献   
7.
The effects of bilateral nucleus accumbens microinjections ofd-ala-met-enkephalinamide (DALA) were assessed in behavioral activation and lateral hypothalamic self-stimulation (LHSS) rate-frequency curve-shift paradigms in normal and accumbens 6-OHDA (4.0 µg) treated rats. Microinjections of DALA (2.5 µg/µl) in the behavioral activation paradigm had little effect on normal activity; however, DALA administered to 6-OHDA treated rats produced a significant overall increase in locomotion. The 6-OHDA DALA-induced locomotion effect peaked at 2 weeks after 6-OHDA treatment and then returned to baseline levels by week 5 posttreatment. Using LHSS, DALA tested over a range of doses (2.5, 5, 10, 20 µg/µl) displayed a weak biphasic reward effect only at the highest dose, which was characterized by an initial suppression followed by an elevation. DALA significantly depressed initial operant motor/performance in LHSS in a dose dependent fashion. Micro-injections of the normally ineffective low dose of DALA (2.5 µg/µl) following accumbens 6-OHDA treatment produced a significant LHSS reward decrease 2 weeks posttreatment, while LHSS motor/performance was relatively unaffected. Results are discussed in terms of opiate-dopamine and limbic-motor interactions.  相似文献   
8.
Cocaethylene, a psychoactive metabolite resulting from combined ethanol/cocaine consumption, is of interest because its psychostimulant properties may partially underlie combined cocaine/ethanol use, and because it has the potential for use as a probe of drug reward mechanisms due to its enhanced selectivity at monoamine uptake sites compared to cocaine. To determine the relative systemic bioavailabilities of cocaine and cocaethylene, sequential plasma samples were obtained from awake rats following drug administration. Following intravenous administration of 3 µmol/kg (molar equivalent of 1 mg/kg cocaine-HCl), both drugs achieved similar time courses and areas under the plasma concentration versus time curve. In contrast, intraperitoneal administration of 44 µmol/kg (molar equivalent of 15 mg/kg cocaine HCl) showed peak plasma levels, and the area under the plasma concentration vs time curve for cocaine to be approximately twice that for cocaethylene. Comparison of dose corrected areas under the curve of the two routes of administration for each drug indicated that relative systemic bioavailability of cocaethylene following intraperitoneal administration is only 58% that of cocaine. In addition, the elimination of both cocaine and cocaethylene was found to be slower following intraperitoneal administration compared to the intravenous route. The implications of these results are discussed with respect to the relative potency of these two compounds, as inferred from behavioral, drug reward, and lethality studies. Also, the differences noted will need to be taken into account when making mechanistic interpretations from comparative drug reward studies.  相似文献   
9.
目的 研究集成电路芯片制造中作业人员的操作特点、接触职业病危害种类以及事故类型。方法 对集成电路芯片制造的生产流程、职业病危害及接触状况的资料进行收集整理。结果 根据生产流程中使用的设备及芯片制造所用原辅材料,论述了生产过程中各设备和操作工序涉及的各类高度、中度毒性化学物质、工艺特殊气体以及电离辐射和非电离辐射等职业病危害因素、作业人员操作特点和易发事故种类。结论 集成电路芯片制造中职业病危害问题值得关注。  相似文献   
10.
张胜九  万兵 《医疗设备信息》2007,22(12):115-116
介绍了阿洛卡SSD2000开关电源的工作原理和常见故障的检修方法。  相似文献   
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