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41.
Background: Leukoaraiosis has been shown to impact functional outcomes after acute ischemic stroke. However, its association with domain specific recovery after ischemic stroke is uncertain. We sought to determine whether pre-existing leukoaraiosis is associated with short-term motor and cognitive recovery after stroke. Methods: We retrospectively studied ischemic stroke patients admitted to acute inpatient rehabilitation (AIR) between January 2013 and September 2015. Patient baseline characteristics, infarct volume, prestroke modified Rankin Scale, stroke cause, rehabilitation length of stay, and Functional Independence Measure (FIM) scores were recorded. Leukoaraiosis severity was graded on brain magnetic resonance imaging using the Fazekas scale. Multiple linear regression was used to determine factors independently associated with the total, cognitive, and motor FIM scores at AIR discharge, respectively. Results: Of 1600 ischemic stroke patients screened, 109 patients were included in the final analysis. After adjustment, the initial National Institute of Health Stroke Scale (β ?0.541, confidence interval [CI] ?0.993 to ?0.888; P = 0.020) and pre-existing leukoaraiosis severity (β ?1.448, CI ?2.861 to ?0.034; P = 0.045) independently predicted the total FIM score. Domain specific analysis showed that infarct volume (β ?0.012, CI ?0.019 to ?0.005; P = 0.002) and leukoaraiosis severity (β ?0.822, CI ?1.223 to ?0.410; P = 0.0001) independently predicted FIM cognitive scores at discharge from AIR. Leukoaraiosis did not predict FIM motor score (P = 0.17). Conclusions: Leukoaraiosis severity is an independent predictor of total and cognitive, but not motor FIM scores after AIR for acute ischemic stroke. This highlights that leukoaraiosis affects poststroke recovery in a domain specific fashion, information that may aid counseling of patients and families as well as tailor rehabilitative efforts.  相似文献   
42.
复方颐神养脑胶囊对多发性脑梗死痴呆大鼠的影响   总被引:1,自引:0,他引:1  
目的:观察中药复方颐神养脑胶囊(YSYN)对大鼠多发性脑梗死痴呆(MID)的疗效及作用机制。方法:3月龄SD大鼠90只,于左侧颈外动脉注入复合血栓诱导剂,复制多发性脑梗死痴呆模型,动物随机分为模型组、YSYN高剂量组(960 mg·kg-1)、YSYN中剂量组(480 mg·kg-1)、YSYN低剂量组(240 mg·kg-1)、西药阳性组(易倍申)(0.5 mg·kg-1)以及YSYN合西药阳性药组(480 mg·kg-1+0.5 mg·kg-1),另设10只动物为假手术组,造模后第3天,各组均以10 mL·kg-1灌胃给药,1次/d,连续4周,模型组和假手术组给予等量蒸馏水。采用Morris水迷宫法进行学习记忆测试;采用酶联免疫法测定海马组织去甲肾上腺素(NE)水平;采用比色法测定海马组织乙酰胆碱酯酶(AchE)、乙酰胆碱转移酶(CHAT)和谷胱甘肽过氧化物酶(GSH-Px)水平。结果:与假手术组比较,模型组大鼠学习记忆能力显著降低(P<0.05,P<0.01),海马组织AchE含量显著升高(P<0.05),海马组织CHAT、NE以及GSH-Px含量显著降低(P<0.01);与模型组比较,YSYN能够显著提高多发性脑梗死痴呆大鼠学习记忆能力(P<0.05);显著降低多发性脑梗死痴呆大鼠海马组织AchE含量,提高多发性脑梗死痴呆大鼠海马组织CHAT、NE及GSH-Px含量(P<0.05,P<0.01)。结论:YSYN对MID具有良好的保护作用,其作用机制可能是通过调节海马组织内去甲肾上腺素、乙酰胆碱及谷胱甘肽的活性来实现的。  相似文献   
43.
背景:运动性疲劳的发生、恢复是否与脑脊液循环存在着某种联系? 目的:观察递增负荷运动后大鼠大脑皮质和脑脊液中去甲肾上腺素、5-羟色胺的动态变化及其相关性。 方法:随机将30只雄性SD大鼠分为对照组10只,运动组20只,运动组采用6周递增负荷运动方案训练,游泳时间由第1周的10 min递增为第6周的60 min,负重由体质量的3%增至体质量的5%。对照组正常饲养。 结果与结论:高效液相色谱检测结果显示,递增负荷运动后即刻,大鼠大脑皮质和脑脊液中去甲肾上腺素、5-羟色胺的水平显著增高;递增负荷运动后24 h,大鼠大脑皮质中去甲肾上腺素、5-羟色胺水平继续增高(P < 0.01),而脑脊液中去甲肾上腺素、5-羟色胺降至正常水平。其中,递增负荷运动后即刻,大鼠大脑皮质中的去甲肾上腺素与5-羟色胺水平及呈显著正相关(P < 0.05),大脑皮质和脑脊液中的去甲肾上腺素及5-羟色胺水平高度相关(P < 0.01)。提示递增负荷运动后去甲肾上腺素的兴奋作用和5-羟色胺的抑制作用处于动态平衡中。递增负荷运动后的即刻,脑脊液中去甲肾上腺素、5-羟色胺的变化能够反映大脑皮质中去甲肾上腺素、5-羟色胺的变化。  相似文献   
44.
Serotonin-specific reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) are antidepressant drugs commonly used to treat a wide spectrum of mood disorders (Wong and Licinio, 2001). Although they have been clinically used for more than 50 years, the molecular and cellular basis for the action of SSRIs and SNRIs is not clear. Considering that the changes in gene expression involved in the action of antidepressant drugs on memory have not been identified, in this study we investigated the impact of chronic treatment with a SSRI (fluoxetine) and a SNRI (venlafaxine) on the mRNA expression of genes related to memory cascade in the mouse hippocampus, namely, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), nitric oxide synthase 1 (NOS1), neurotrophic tyrosine kinase receptor type 2 (TrKB), mitogen-activated protein kinases (MAPK/ERK) and serotonin transporter (SERT). Animals treated with fluoxetine 10 mg/Kg/day for 28 days showed a significant decrease in the percentage of time spent in the novel object recognition test (p≤0.005) and induced MAPK1/ERK2 down-regulation (p=0.005). Our results suggest that the effect on cognition could probably be explained by fluoxetine interference in the MAPK/ERK memory pathway. In contrast, chronic treatment with venlafaxine did not reduce MAPK1/ERK2 expression, suggesting that MAPK1/ERK2 down-regulation is not a common effect of all antidepressant drugs. Further studies are needed to examine the effect of chronic fluoxetine treatment on the ERK-CREB system, and to determine whether there is a causal relationship between the disruption of the ERK-CREB system and the effect of this antidepressant on memory performance.  相似文献   
45.
Although few surgeons dispute the benefits of high-potassium crystalloid cardioplegia, objective comparison of the efficacy of various formulations is difficult in clinical practice. We compared four commonly used cardioplegic solutions in the isolated rat heart (N = 6 for each solution) subjected to 180 minutes of hypothermic (20 degrees C) ischemic arrest with multidose cardioplegia (3 minutes every half-hour). The clinical solutions studied were St. Thomas' Hospital solution, Tyers' solution, lactated Ringer's solution with added potassium, and a balanced saline solution with glucose and potassium. Postischemic recovery of function was expressed as a percentage of preischemic control values. Release of creatine kinase during reperfusion was measured as an additional index of protection. St. Thomas' Hospital solution provided almost complete recovery of all indexes of cardiac function following ischemia including 88.1 +/- 1.6% recovery of aortic flow, compared with poor recovery for the Tyers', lactated Ringer's, and balanced saline solutions (20.6 +/- 6.5%, 12.5 +/- 6.4%, and 9.6 +/- 4.2%, respectively) (p less than 0.001). Spontaneous defibrillation was rapid (less than 1 minute) and complete (100%) in all hearts in the St. Thomas' Hospital solution group, but much less satisfactory with the other formulations. Finally, St. Thomas' Hospital solution had a low postischemic level of creatine kinase leakage, contrasting with significantly higher enzyme release in the other solutions tested (p less than 0.001). Although differences in composition are subtle, all potassium crystalloid cardioplegic solutions are not alike in the myocardial protection they provide. Comparative studies under controlled conditions are important to define which formulation is superior for clinical application.  相似文献   
46.
The adrenal gland is a common site of metastasis from carcinoma of the lung. In selected patients, especially those in whom the adrenal mass is on the ipsilateral side of the lung lesion, the adrenal gland can be biopsied by a transthoracic transdiaphragmatic approach. Our technique of transdiaphragmatic adrenal biopsy in the staging of carcinoma of the lung is described.  相似文献   
47.
无先兆偏头痛患者血单胺类递质变化的研究   总被引:4,自引:0,他引:4  
目的 了解5-羟色胺(5-TH)、5-羟吲哚乙酸(5-HIAA)、多巴胺(DA)、去甲肾上腺素(NE)在无先兆偏头痛发病中的作用。方法 用荧光分光光度法检测35例无先兆偏头痛患者(发作期16例、间歇期19例)和23例正常人血浆及血小板5-HT、5-HIAA、DA、NE含量。结果 无先兆偏头痛患者发作期组血浆5-HT含量低于对照组(P<0.05),而5-HIAA含量高于对照组(P<0.01);间歇期组5-HT含量高于发作期组,而5-HIAA含量低于发作期组(P<0.01);发作期组血浆DA、NE含量均低于对照组(P<0.01)间歇期组血浆DA与发作期组相比亦有显著性差异(P<0.01)。无先兆偏头痛患者发作期组血小板5-HT含量高于对照组和间歇期组,而5-HIAA含量低于对照组和间歇期组(P<0.01);而发作期组血小板NE含量高于对照组和间歇期组(P<0.01);DA含量则低于对照组和间歇期组(P<0.01)。结论 单胺类递质对偏头痛的发生可能有重要意义。  相似文献   
48.
Laryngeal aerodynamics associated with selected voice disorders   总被引:1,自引:0,他引:1  
Measures of estimated subglottal air pressure and laryngeal air flow during speech production are compared for adults with normal laryngeal function and those with laryngeal abnormalities. The most traditional measure, air flow during sustained vowel production, is not a strong predictor of laryngeal function during speech production. Subglottal air pressure and laryngeal air flow offer insight into voice disorders and provide directions for therapy as well as a method for the quantitative assessment of treatment outcomes.  相似文献   
49.
Fourteen women experiencing early pregnancy failure have been studied during the time of conception and at frequent intervals until spontaneous abortion occurred. Serial measurements of serum estradiol, progesterone, 17α-hydroxyprogesterone, prolactin, human placental lactogen (hPL), and human chorionic gonadotropin (hCG) were determined; regular sonar scanning allowed the time of fetal death to be determined to within 7 days in six patients and a diagnosis of blighted ovum to be made in the remainder. In all patients serum progesterone and estradiol concentrations were within the normal range up to 7 weeks but appeared to decrease from about 8 weeks' gestation whether or not a living fetus was present. The placenta continued to produce hCG and hPL but, despite the continuing presence of hCG, the levels of 17α-hydroxyprogesterone declined to concentrations below those associated with normal pregnancy. These data suggest that the placenta may require a particular stimulus to take over production of progesterone and estradiol.  相似文献   
50.
Rats were implanted with bipolar fine wire stimulating electrodes in the region of the pontine nucleus locus coerulus (LC) and the pars compacta of the substantia nigra (SN). The reinforcing properties of stimulation of each electrode were determined. Subsequently, rats were run in a two alley runway and the effects of priming stimulation on performance in acquisition, discrimination and reversals were measured. It was found that LC priming caused an increased latency to exit from start box. Also, LC priming reduced running time in the rewarded alley in a reversal task whereas SN priming affected both performance in the rewarded and non-rewarded alley.  相似文献   
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