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91.
1. Elevated proinflammatory cytokines within the central nervous system (CNS) of individuals infected with human immunodeficiency virus (HIV) may contribute to altered CNS processes prior to the onset of AIDS. Most studies of HIV-induced alterations in cytokine expression within the CNS have focused on interleukin (IL)-1 and tumor necrosis factor (TNF).2. We used a ribonuclease protection assay (RPA) to elucidate further the pattern of cytokine mRNA expression in the rat CNS in response to HIV envelope glycoprotein 160 (gp160). Male Sprague–Dawley rats were surgically implanted with a guide cannula directed into a lateral cerebral ventricle. HIV gp160 was injected intracerebroventricularly and rats were sacrificed immediately (time = 0) or at 1, 2, or 4 hr postinjection. Discrete brain regions were dissected, and peripheral glands removed. All tissues were frozen in liquid nitrogen until RNA extraction and assay.3. IL-1, IL-1, TNF-, and TNF mRNAs were constitutively expressed in brain tissues. Central administration of gp160 dramatically increased mRNA expression for IL-1 and TNF in the hypothalamus, hippocampus, brainstem, and cerebellum. Furthermore, although mRNA expression for IL-5, IL-6, and IL-10 was never detected under basal conditions, these mRNAs were increased in brain tissue after administration of gp160. Peak expression in each brain region was detected 2 hr after administration. Multiple cytokine mRNAs were detected in peripheral tissues, but their expression was not altered by central administration of gp160.4. Our results indicate that gp160 induces mRNA expression in brain for cytokines other than IL-1 and TNF. Screening for multiple cytokine mRNA in this manner provides extensive information concerning the particular cytokines that may be involved in HIV-induced pathologies and alterations in CNS processes.  相似文献   
92.
We studied the dynamical behavior of a class of compound central pattern generator (CPG) models consisting of a simple neural network oscillator driven by both constant and periodic inputs of varying amplitudes, frequencies, and phases. We focused on a specific oscillator composed of two mutually inhibiting types of neuron (inspiratory and expiratory neurons) that may be considered as a minimal model of the mammalian respiratory rhythm generator. The simulation results demonstrated how a simple CPG model— with a minimum number of neurons and mild nonlinearities— may reproduce a host of complex dynamical behaviors under various periodic inputs. In particular, the network oscillated spontaneously only when both neurons received adequate and proportionate constant excitations. In the presence of a periodic source, the spontaneous rhythm was overriden by an entrained oscillation of varying forms depending on the nature of the source. Stable entrained oscillations were inducible by two types of inputs: (1) anti-phase periodic inputs with alternating agonist-antagonist drives to both neurons and (2) a single periodic drive to only one of the neurons. In-phase inputs, which exert periodic drives of similar magnitude and phase relationships to both neurons, resulted in varying disruptions of the entrained oscillations including magnitude attenuation, harmonic and phase distortions, and quasi-periodic interference. In the absence of significant phasic feedback, chaotic motion developed only when the CPG was driven by multiple periodic inputs. Apneic episodes with repetitive alternation of active (intrinsic oscillation) and inactive (cessation of oscillation) states developed when the network was driven by a moderate periodic input of low frequency. %and amplitudes of intermediate strength, Similar results were demonstrated in other, more complex oscillator models (that is, half-center oscillator and three-phase respiratory network model). These theoretical results may have important implications in elucidating the mechanisms of rhythmogenesis in the mature and developing respiratory CPG as well as other compound CPGs in mammalian and invertebrate nervous systems.  相似文献   
93.
Asperger's Syndrome (AS) is a pervasive developmental disorder whose continuity with High-Functioning Autism is still a matter of debate. Clinical observations suggest that patients with AS may present the same sleep disorders as autistic patients, including difficulties in initiating and maintaining sleep as well as poor dream recall. We recorded the sleep of a 25-year-old male patient with AS for two nights using a full EEG montage and compared the second night to that of a group of normal participants. We found low levels of slow wave sleep (SWS: stages 3 + 4), high levels of stage 1, and a large number of awakenings. The organization of REM sleep was unremarkable, including normal REM density. Analyses of phasic EEG events revealed a very low incidence of sleep spindles and a normal number of K-complexes over bilateral frontal and central EEG leads. In order to collect dream reports, the patient was awakened three times over two nights following at least 15 minutes of REM sleep in each case. On each occasion the patient was not aware of any mental activity happening just prior to awakening. These observations are discussed with regards to the connections that may exist between EEG sleep spindle activity, selective attention, and the capacity to generate a dream report.  相似文献   
94.
目的:探讨运动疗法对慢性阻塞性肺疾病(COPD)患者抑郁状态的临床效果。方法:选取52例COPD患者,随机分为试验组和对照组,各26例。对照组给予支气管扩张、健康教育、氧疗,试验组在对照组的基础上实施运动疗法,采用焦虑自评量表(SAS)、抑郁自评量表(SDS)、ADL生活质量量表对两组患者治疗前后进行评估。结果:对照组患者SAS、SDS评分治疗前后无明显变化,试验患者SAS、SDS评分均明显低于治疗前(P0.05),两组治疗后组间比较,差异亦有统计学意义(P0.05);试验组生活质量的改善优于对照组(P0.05)。结论:运动疗法能有效的改善COPD患者焦虑、抑郁负性情绪,提高患者的生存质量。  相似文献   
95.
目的:COPD是严重威胁人类健康的慢性呼吸系统疾病,而目前的治疗手段均不理想。氧化应激在COPD发病机制中发挥重要作用,而氢气具有选择性抗氧化特性。因此探讨氢气对COPD是否具有保护作用具有重要的现实意义。方法:采用被动吸烟法建立大鼠COPD模型,建模成功后对模型动物进行氢气吸入治疗。通过动物肺功能检测、肺组织形态学观察评价氢气对COPD是否具有治疗作用。并进一步通过检测血清及肺组织中MDA水平,以及肺组织中炎性因子水平初步探讨其可能的作用机制。结果:持续8周的烟熏造模,使大鼠体重Lee's指数显著降低,而氢气治疗2周后,Lee's指数较模型组有明显改善。动物肺功能检测显示,持续烟熏使大鼠肺气道阻力明显增加,潮气量和肺顺应性明显降低;氢气吸入治疗2周后,与COPD模型组相比,大鼠肺气道阻力、潮气量和肺顺应性均有明显改善。氢气可以明显改善烟熏引起的肺组织病理改变。氢气对烟熏引起血清及肺组织内MDA、TNF-α、IL-1β水平升高具有明显的抑制作用。结论:吸入氢气对烟熏引起的大鼠COPD具有明显的治疗作用。  相似文献   
96.
目的:探讨右美托咪定对慢性阻塞性肺疾病急性加重期(AECOPD)患者机械通气的镇静效果和安全性。方法:选取2012年6月-2014年9月在我院接受气管插管呼吸机辅助通气治疗的AECOPD患者62例,并将其随机分为实验组和对照组。其中,对照组患者给予常规治疗,实验组在常规治疗的基础上给予右美托咪镇痛。观察和比较两组患者机械通气持续时间、ICU停住时间、呼吸机相关性肺炎(VAP)、心动过缓和谵妄的发生率。结果:实验组患者机械通气时间及ICU停住时间均明显短于对照组,VAP、心动过缓及谵妄的发生率均显著低于对照组,差异均具有统计学意义(P0.05)。结论:右美托咪定对行机械通气慢性阻塞性肺疾病急性加重期患者良好的镇静效果,且安全性高,值得临床推广。  相似文献   
97.
目的:观察MMP-1、MMP-3 和MMP-13 在慢性睡眠剥夺所致颞下颌关节损伤中表达的变化,探讨慢性睡眠剥夺所致颞下颌 关节损伤的可能机制。方法:采用改良多平台(MMPM)建立大鼠慢性睡眠剥夺模型,将90 只成年雄性Wastar 大鼠随机分为小平 台组、网格组和对照组。小平台组和网格组大鼠接受每天18 h的睡眠剥夺和6 h间歇期(10:00-16:00),间歇期大鼠正常笼养。实验 第7、14 和21 d时分别观察动物的行为学观察、检测动物血浆皮质醇(CORT)和促肾上腺皮质激素(ACTH)水平检测,通过免疫印 迹法和实时定量聚合酶链反应(PRC)检测颞下颌关节软骨中MMP-1、MMP-3 和MMP-13 的蛋白和mRNA表达,并通过HE 染色 法观察颞下颌关节结构的变化。结果:与对照组和网格组大鼠相比,小平台组大鼠第14 d和21 d 时髁突软骨中间部位表面纤维 在出现明显的炎症、松解及脱落现象;第21天时的血浆ACTH 和CORT 水平均显著高于网格组和对照组,差异有统计学意义 (P<0.05);第7、14、21 d时关节软骨MMP-1 和MMP-13 蛋白和mRNA 的表达水平均显著上调(P<0.05)。结论:慢性睡眠剥夺所致 的颞下颌关节损伤可能与关节软骨中MMP-1、MMP-3 和MMP-13 的表达上调有关。  相似文献   
98.
99.
Summary We introduce a correction for covariate measurement error in nonparametric regression applied to longitudinal binary data arising from a study on human sleep. The data have been surveyed to investigate the association of some hormonal levels and the probability of being asleep. The hormonal effect is modeled flexibly while we account for the error‐prone measurement of its concentration in the blood and the longitudinal character of the data. We present a fully Bayesian treatment utilizing Markov chain Monte Carlo inference techniques, and also introduce block updating to improve sampling and computational performance in the binary case. Our model is partly inspired by the relevance vector machine with radial basis functions, where usually very few basis functions are automatically selected for fitting the data. In the proposed approach, we implement such data‐driven complexity regulation by adopting the idea of Bayesian model averaging. Besides the general theory and the detailed sampling scheme, we also provide a simulation study for the Gaussian and the binary cases by comparing our method to the naive analysis ignoring measurement error. The results demonstrate a clear gain when using the proposed correction method, particularly for the Gaussian case with medium and large measurement error variances, even if the covariate model is misspecified.  相似文献   
100.
目的:探讨经皮肾微造瘘术后Ⅱ期经皮输尿管镜治疗输尿管上段结石致孤立肾急性肾功能衰竭的安全性与有效性。方法:从2004年7月~2009年5月,利用经皮肾微造瘘建立经皮肾通道,引流1周后肾功能明显好转,再行经皮肾输尿管镜碎石治疗孤立肾输尿管上段结石。结果:16例患者中,所有患者均为单通道取石,结石清除率例(81.2%),未出现高热、出血等并发症。术后1月复查13例无结石残留。结论:微创经皮输尿管镜分期治疗输尿管上段结石致孤立肾急性肾功能衰竭是安全、有效的,同传统经皮肾镜相比,具有对病人创伤小,易恢复等优点。  相似文献   
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