中枢5-羟色胺缺损引起的高血压及其中枢机理

目的：建立中枢５羟色胺（５－ＨＴ）缺损所致的实验性高血压大鼠（ＥＨＲ）模型并探讨其中枢机理。方法：侧脑室埋植瘘管及药物注射。大鼠尾动脉血压及心率启示仪记录清醒大鼠动脉压（ＡＰ）及心率（ＨＲ）。高效液相色谱－电化学检测法ＨＰＬＣ－ＥＣＤ）检测大鼠脑内单胺类递质含量。结果：（１）给大鼠侧脑室（ＩＣＶ）注射选择性神经化学切除剂５,６－双羟色胺（５,６－ＤＨＴ）引起中枢５－ＨＴ神经元缺损,使脑同５－ＨＴ含     

运动性中枢疲劳后脊髓内主要神经递质含量的变化

目的：研究运动性中枢疲劳后脊髓内主要单胺类及氨基酸类神经递质含量的变化,探索运动性疲劳脊髓水平发生机制。方法：运用：Bedford递增负荷运动训练方案建立运动性中枢疲劳模型。将18只雄性成年Wistar大鼠随机分为对照组（C）,训练后即刻组（IT）及训练后3 h恢复组（RT）。用高效液相色谱法（HPLC）检测脊髓内单胺类和氨基酸类神经递质含量的变化。结果：大鼠脊髓内氨基酸类神经递质,在训练后即刻都出现了增高,其中谷氨酸（Glu）、γ-氨基丁酸（GABA）明显增高（P〈0.05）,甘氨酸（Gly）也出现增高但与对照组相比无显著性差异 训练后经3 h恢复后,氨基酸类神经递质含量基本恢复至对照组水平。单胺类神经递质,去甲肾上腺素（NE）,5-羟色胺（5-HT）在训练后即刻则出现降低趋势,且5-羟色胺（5-HT）含量在训练后3 h恢复组出现了明显降低（P〈0.05）。结论：运动性疲劳引起脊髓内神经递质含量的改变,可能与运动性中枢疲劳的发生过程有关。脊髓5-HT在恢复期仍明显降低,提示5-HT可能与疲劳恢复过程有较为密切的关系。     

脑桥呼吸调整中枢向中缝大核下行投射的研究

实验在23只苯巴比妥钠麻醉(i.p.30mg/kg)的成年猫上进行。在脑桥呼吸调整中枢(NPBM-KF)共记录到67个单位放电可被电刺激中缝大核(NRM)所逆行兴奋。其中有7个单位为呼吸相关性单位(吸气性6、呼气性1),占脑桥87个呼吸相关性单位总数的8％。逆行兴奋潜伏期在0.4—2.5ms之间,平均1.2ms。中缝大核内微量注入麦角辣根过氧化酶(WGA-HRP)后在NPBM-KF区观察到大量HRP标记神经元。本实验结果表明,发自脑桥呼吸调整中枢神经元的轴突可投射到中缝大核。这一投射通路可能与呼吸及痛觉调节有关。     

鸣禽鸟听觉低级中枢的研究

本文用辣根过氧化物酶注入鸣禽鸟蜡嘴雀和锡嘴雀，耳蜗内顺行追踪方法，均在不同侧延脑的ＮＭ和ＮＡ获标记纤维。结果表明蜡嘴和锡嘴雀听觉低级中枢由ＮＭ和ＮＡ两部分组成。     

脉冲电流经皮刺激肝区对运动性疲劳大鼠5-HT及其代谢的影响

目的:研究脉冲电流经皮刺激肝区对运动性疲劳大鼠大脑纹状体5-羟色胺(5-HT)及其代谢的影响。方法:8周龄Wistar雄性大鼠80只随机分为安静对照组(CG组)、疲劳训练组(FG组)、运动后刺激组(SAF组)、运动前刺激组(SBF组),除CG组外各组均进行游泳训练,建立运动疲劳模型,于第1、3、5周训练的最后1d,断头处死,取外周血测游离色氨酸(F-Trp)、支链氨基酸(BCAA)、F-Trp/BCAA含量,取纹状体测F-Trp、5-HT、5-羟吲哚乙酸(5-HIAA)含量。结果:与CG组相比,各组大鼠血清BCAA含量呈下降趋势,其余各指标均呈升高趋势;与FG组相比,SAF组、SBF组第3周末纹状体5-HT明显下降(P0.01);与SBF组相比,SAF组第5周末纹状体5-HT明显下降(P0.05)。结论:经皮脉冲电流刺激具有降低疲劳大鼠5-HT及代谢产物的含量,有助于疲劳的消除,对长时间运动时中枢机能的改善具有积极作用。     

自发性高血压大鼠中枢去甲肾上腺素与血管紧张...

The norepinephrine (NE) and angiotensin II (A II) contents in the brain regions of SHR and WKY (Wistar Kyoto) rats at different ages were determined by fluorospectrophotometry and radioimmunoassay. The systolic blood pressure (SBP) of the rats was measured indirectly with a tail cuff technique in conscious state. The results were as follows: There was no significant difference in the central A II and NE contents between SHR and WKY rats at 8-week age. Since 12th week age the SBP of SHR has increased gradually, up to 16th to 20th week and then maintained steady level. Whereas there was no significant change of SBP in WKY rats in the same span of age. In the early and late states of hypertension the A II contents in the medulla oblongata, pons, hypothalamus and nucleus caudatus of SHR were markedly higher than those of the age-matched WKY rats. But the change of NE content of SHR in the early stage showed a different picture as compared with that of WKY rats, i.e., NE decreased in medulla oblongata and anterior hypothalamus but increased in pons, posterior hypothalamus and nucleus caudatus. However, in the late stage there was no such significant difference between SHR and WKY rats. Consequently, it is suggested that the central A II and NE participated in the development of hypertension of SHR, and that the maintenance of hypertension is mainly dependent upon the increased A II content. Microinjection of captopril or 6-OHDA in the lateral cerebroventricle of SHR elicited a decrease of BP and reduction of both A II and NE contents in the medulla and hypothalamus.(ABSTRACT TRUNCATED AT 250 WORDS)     

鸡中枢淋巴器官肥大细胞的组织化学与形态学

对哺乳动物的,特别是啮齿动物和人类肥大细胞已有了比较深入的研究, 但关于家禽肥大细胞的研究很少.本研究旨在阐明鸡中枢淋巴器官中肥大细胞的组织化学与形态学特征.本研究证实Carnoy 氏液是鸡肥大细胞的优良的固定液,而中性缓冲福尔马林(NBF) 却阻断了大多数肥大细胞的着染力.甲苯胺蓝和阿尔新蓝是鸡肥大细胞的良好的染料,但阿尔新蓝能使更多的肥大细胞着染,虽然其也可使杯状细胞着染.作者的一种新的染色法, 长时间阿尔新蓝染色(LAB-S)可用于NBF固定的组织中肥大细胞的染色,因为其着染的细胞数与Carnoy 氏液固定甲苯胺蓝染色的细胞数无显著差异(P<0.001).在胸腺髓质中见有大量的肥大细胞,而胸腺皮质仅可见个别肥大细胞位于血管周围及小叶间结缔组织中.腔上囊的皮质与髓质中很少见有肥大细胞.肥大细胞有血管周围分布的倾向,但一个有趣的发现是血管内偶尔也有个别肥大细胞.电镜下可见肥大细胞的胞浆颗粒内充满无定形的颗粒状基质,但其电子密度有的较高,有的较低.少数胞浆颗粒内有旋涡状及网状亚微结构.但未见有人类肥大细胞胞浆颗粒内特征性的晶格状和卷轴状的亚微结构,也未见到在绵羊肥大细胞中描述过的特殊亚微结构.     

慢性应激动脉粥样硬化动物模型和应激与AS的发生研究进展

动脉粥样硬化(Atherosclerosis,AS)是缺血性心脑血管病的主要病理基础,环境、遗传等多因素共同影响下都能促进AS的形成与发展,越来越多研究表明慢性应激对于AS形成起到关键的作用,慢性应激可通过过度激活交感神经系统、肾素-血管紧张素系统与下丘脑-垂体-肾上腺皮质轴促进AS的形成,并且与Toll样受体、肿瘤坏死因子α、白细胞介素-6、脂联素等因素有密切联系。在研究慢性应激与AS发生的模型中,目前Apo E-/-小鼠、SD大鼠、Wistar大鼠等啮齿类动物仍然是主要模型,灵长类动物模型研究虽然更具有临床意义,但由于其成本、数量等因素限制了广泛使用。本文主要就慢性应激与AS的动物模型研究、慢性应激促进AS发生发展的相关机制进行综述。     

大鼠运动性疲劳模型的建立

目的建立大鼠运动疲劳模型,观察运动疲劳对大鼠各项生理、生化指标的影响。方法20只大鼠随机分为正常对照组和运动疲劳模型组,运动疲劳模型组大鼠每日按照方案进行锻炼。实验结束后大鼠检测相关指标：血清MDA含量和红细胞SOD活性,肝脏与骨骼肌MDA含量、SOD活性,骨骼肌线粒体游离钙离子含量,骨骼肌线粒体膜电位,下丘脑神经递质。电镜观察骨骼肌线粒体细微结构。结果运动疲劳模型组大鼠造模2周以后其血清、肝和骨骼肌MDA含量均有显著升高,红细胞和骨骼肌SOD活性均有显著降低,骨骼肌线粒体膜电位显著性降低,骨骼肌线粒体游离Ca2＋含量有显著性降低,下丘脑GABA、5-HT含量有显著升高,下丘脑DA、ACh含量有显著性下降,电镜观察显示骨骼肌超微结构改变并以线粒体改变较为明显。结论大鼠跑台运动2周可造成运动疲劳模型,并造成大鼠骨骼肌线粒体损伤。     

疲劳引起的轻度认知功能障碍的诊疗研究进展

疲劳引起的包括易受到无关信息的干扰、工作错误率增加,任务检测能力和策略性行为调整的能力下降等表现,属轻度认知功能障碍(MCI)范畴。本文对疲劳引起的轻度认知功能障碍的中西医研究进展进行整理。从其涉及的神经生理学机制、中医对其病因病机的认识、中西医特色治疗方面进行了总结,并结合高新技术发展趋势对其生理学机制研究及诊疗的发展进行展望,为今后的研究提供新思路。     

2型糖尿病鼠类模型的研究进展

小鼠、大鼠糖尿病模型对基础与临床防治研究十分重要,不同的研究目标对应不同的动物模型载体。本文就目前常用的2型糖尿病鼠类模型的构建、主要疾病特征及应用等进行评述,为研究者了解、选择适合的动物模型提供参考。     

大气氮沉降对中亚草地生态系统净初级生产力的影响

氮沉降作为除气候变化、CO₂浓度升高以及土地利用变化之外的第四大主要影响陆地生态系统结构和功能的因素,其对碳循环过程的影响研究相对薄弱,同时也是不确定性最大的环节之一。近年来,由于长期高强度的放牧导致草地生态系统的生产力降低,氮成为典型草地植物生长和生态系统净初级生产力的主要限制因子。据研究,亚洲的氮沉降平均增速极有可能高于全球氮沉降平均增速,成为未来氮沉降增加最快的区域。在此背景下,研究大气氮沉降对于中亚草地生态系统的影响具有重要的意义。利用反硝化-分解模型（DNDC）分析1979-2014年中亚地区草地生态系统净初级生产力（NPP）的时空分异,探讨氮沉降对草地NPP影响。结果表明：（1）1979-2014年间,中亚地区平均草地NPP约为（173.10±31.80） g C m^-2 a^-1,草地NPP时空分异明显,各草地类型的NPP从大到小依次为森林草甸、温带草原和荒漠草原,并且草地NPP以（2.67±1.30） g C m^-2 a^-1的速度逐年增长;（2）当前氮沉降情景总体上促进了中亚地区草地NPP的增长,1979-2014年氮沉降使得中亚草地NPP增加了0.42 Pg C。     

羊肚菌抗疲劳作用研究

通过观察服用了羊肝菌的小鼠负重游泳试验、血清尿素氮测定试验结果、肝糖原测定结果及血乳酸测定结果表明,肚菌粉在一定的剂量时,具有抗疲劳作用。     

Force variability depends on core and muscle temperature

The aim of this study was to investigate if voluntary activation and force variability during maximal voluntary contraction (MVC) depends more on muscle (local) or body (core) temperature. Ten volunteers performed a 2-min MVC of the knee extensors under the control (CON) conditions (ambient temperature (21 °C), relative humidity (30%), and air velocity (∼0.1 m/s)) as well as after heating (HT) and cooling (CL) of the lower body. During water manipulation procedure lower body was immersed up to the waist in a water bath at ∼44 °C for 45 min for HT experiment, and ∼15 °C for 30 min for CL experiment. Peak torque, torque variability, muscle voluntary activation and half-relaxation time were assessed during the exercise. HT increased muscle (2.8±0.2 °C) and rectal (1.9±0.1 °C) temperatures while CL lowered muscle (2.2±0.2 °C) temperature, but did not affect rectal temperature. During 2-min MVC, peak torque decreased (P<0.05; SP>90%) and to a lower level in HT compared to CON and CL experiments (52.6±2.3% versus 69.0±2.3% and 65.6±1.9% MVC, respectively, P<0.05; SP>90%). Torque variability increased significantly during exercise and was significantly larger in HT and lower in CL compared to CON experiment. Voluntary activation of exercising muscle was more depressed in HT (i.e. greater central fatigue) and the smallest effect was found in CL compared to CON. In conclusion increased core and muscle temperature impairs voluntary activation and increases force variability of the exercising muscles while a local muscle cooling decrease force variability but has a small effect on central fatigue.     

原发性肝癌患者术后癌因性疲乏的影响因素及其预测模型构建

摘要 目的：分析原发性肝癌患者术后癌因性疲乏（CRF）的影响因素并构建预测模型。方法：选取2020年1月～2023年1月湖南师范大学附属第一医院收治接受手术治疗的200例原发性肝癌患者,根据术后3个月是否存在CRF将患者分为CRF组（124例）和非CRF组（76例）。单因素和多因素Logistic回归分析影响原发性肝癌患者术后CRF的因素并构建其预测模型。通过受试者工作特征（ROC）曲线分析预测模型对原发性肝癌患者术后CRF的预测价值。结果：单因素分析显示,CRF组病程长于非CRF组,Child-Pugh分级B级、美国东部肿瘤协作组功能状态（ECOG）评分1～2分、辅助化疗、医疗付费方式自费、抑郁/焦虑比例高于非CRF组,文化程度高中及以上、家庭月收入＞3000元、高度社会支持度比例低于非CRF组（P＜0.05）。多因素Logistic回归分析显示,病程延长、Child-Pugh分级B级、ECOG评分1～2分、辅助化疗、医疗付费方式自费、抑郁/焦虑为影响原发性肝癌患者术后CRF的独立危险因素,家庭月收入＞3000元、高度社会支持为独立保护因素（P＜0.05）。原发性肝癌患者术后CRF的预测模型方程：Logit（P）=P/1-P=-1.252+0.409×病程+0.839×Child-Pugh分级+1.378×ECOG评分+1.055×辅助化疗+1.476×医疗付费方式-0.793×家庭月收入+0.883×抑郁/焦虑-1.260×社会支持度。霍斯默-莱梅肖检验P＞0.05。ROC曲线分析显示,模型预测原发性肝癌患者术后CRF的曲线下面积为0.910,敏感度为87.10%,特异度为85.53%。结论：病程、Child-Pugh分级、ECOG评分、辅助化疗、医疗付费方式、抑郁/焦虑、家庭月收入、社会支持度为影响原发性肝癌患者术后CRF的因素,基于此构建的预测模型对原发性肝癌患者术后CRF的预测价值较高,可能有助于临床早期发现和干预原发性肝癌患者术后CRF,以改善患者预后。     

Fatigue compensation during FES using surface EMG

Muscle fatigue limits the effectiveness of FES when applied to regain functional movements in spinal cord injured (SCI) individuals. The stimulation intensity must be manually increased to provide more force output to compensate for the decreasing muscle force due to fatigue. An artificial neural network (ANN) system was designed to compensate for muscle fatigue during functional electrical stimulation (FES) by maintaining a constant joint angle. Surface electromyography signals (EMG) from electrically stimulated muscles were used to determine when to increase the stimulation intensity when the muscle’s output started to drop.

In two separate experiments on able-bodied subjects seated in hard back chairs, electrical stimulation was continuously applied to fatigue either the biceps (during elbow flexion) or the quadriceps muscle (during leg extension) while recording the surface EMG. An ANN system was created using processed surface EMG as the input, and a discrete fatigue compensation control signal, indicating when to increase the stimulation current, as the output. In order to provide training examples and test the systems’ performance, the stimulation current amplitude was manually increased to maintain constant joint angles. Manual stimulation amplitude increases were required upon observing a significant decrease in the joint angle. The goal of the ANN system was to generate fatigue compensation control signals in an attempt to maintain a constant joint angle.

On average, the systems could correctly predict 78.5% of the instances at which a stimulation increase was required to maintain the joint angle. The performance of these ANN systems demonstrates the feasibility of using surface EMG feedback in an FES control system.