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21.
目的:观察苇茎汤合麻杏石甘汤加减联合半量激素治疗儿童毒热闭肺型难治性肺炎支原体肺炎的临床疗效。方法:120例患儿随机分为对照组和观察组,各60例。在基础治疗基础上,对照组给予连花清瘟颗粒+甲强尼龙(每次10 mg·kg-1,2次/日),观察组给予苇茎汤合麻杏石甘汤加减+甲强尼龙(每次10 mg·kg-1,1次/日),疗程均为14 d。观察两组治疗前后肺功能指标[最大通气量(MVV),呼气达峰时间(TPTEF),第1秒用力呼气容积(FEV1),呼气达峰容积(VPTEF)],血浆心肌酶谱[肌酸激酶(CK),肌酸激酶同工酶(CKMB),乳酸脱氢酶(LDH),胫丁酸脱氢酶(HBDH)],免疫功能[免疫球蛋白G(IgG),免疫球蛋白M(IgM),红细胞免疫复合物(RBC-ICR),红细胞C3b受体(RBC-C3bR)],炎性因子[肿瘤坏死因子-α(TNF-α),γ-干扰素(IFN-γ),白细胞介素-13(IL-13),白细胞介素-17A(IL-17A)],临床疗效和不良反应。结果:研究期间脱落4例。观察组总有效率96.6%(57/59),高于对照组的84.2%(48/57)(P<0.05)。与对照组治疗后比较,观察组MVV,TPTEF,FEV1,VPTEF,RBC-C3bR,IL-13升高(P<0.05);CK,CKMB,LDH,HBDH,IgG,IgM,RBC-ICR,TNF-α,IFN-γ和IL-17A降低(P<0.05)。观察组不良反应发生率低于对照组(P<0.05)。结论:苇茎汤合麻杏石甘汤加减联合半量激素可明显改善毒热闭肺型难治性肺炎支原体肺炎患儿的肺功能,心肌酶谱,免疫功能和炎性因子水平,不良反应发生率低。  相似文献   
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The insular cortex plays essential roles in nicotine addiction. However, much is still unknown about its cellular and synaptic mechanisms responsible for nicotine addiction. We have previously shown that in layer 5 pyramidal neurons of the mouse insular cortex, activation of the nicotinic acetylcholine receptors (nAChRs) suppresses synaptic potentiation through enhancing GABAergic synaptic transmission, although it enhances both glutamatergic and GABAergic synaptic transmission. In the present study, we examined whether dopamine receptors might contribute to the nicotine‐induced inhibition of synaptic potentiation. The nicotine‐induced inhibition of synaptic potentiation was decreased in the presence of a D1 dopamine receptor antagonist SCH23390 irrespective of the presence of a D2 dopamine receptor antagonist sulpiride, suggesting that D1 dopamine receptors are involved in nicotine‐induced inhibition. We also investigated how dopamine receptors might contribute to the nAChR‐induced enhancement of glutamatergic and GABAergic synaptic transmission. The nAChR‐induced enhancement of GABAergic synaptic transmission was decreased in the presence of SCH23390 irrespective of the presence of sulpiride, whereas that of glutamatergic synaptic transmission was not altered in the presence of SCH23390 and sulpiride. These results suggest that D1 dopamine receptors are involved in the nAChR‐induced enhancement of GABAergic synaptic transmission while dopamine receptors are not involved in that of glutamatergic synaptic transmission. These observations indicate that the interaction between nAChRs and D1 dopamine receptors plays critical roles in synaptic activities in layer 5 pyramidal neurons of the mouse insular cortex. These insular synaptic changes might be associated with nicotine addiction.  相似文献   
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《Brain stimulation》2020,13(3):614-624
BackgroundStudies examining the contribution of contralesional brain regions to motor recovery after stroke have revealed conflicting results comprising both supporting and disturbing influences. Especially the relevance of contralesional brain regions beyond primary motor cortex (M1) has rarely been studied, particularly concerning the temporal dynamics post-stroke.MethodsWe, therefore, used online transcranial magnetic stimulation (TMS) interference to longitudinally assess the role of contralesional (right) frontoparietal areas for recovery of hand motor function after left hemispheric stroke: contralesional M1, contralesional dorsal premotor cortex (dPMC), and contralesional anterior intraparietal sulcus (IPS). Fourteen stroke patients and sixteen age-matched healthy subjects performed motor tasks of varying complexity with their (paretic) right hand. Motor performance was quantified using three-dimensional kinematic data. All patients were assessed twice, (i) in the first week, and (ii) after more than three months post-stroke.ResultsWhile we did not observe a significant effect of TMS interference on movement kinematics following the stimulation of contralesional M1 and dPMC in the first week post-stroke, we found improvements of motor performance upon interference with contralesional IPS across motor tasks early after stroke, an effect that persisted into the later phase. By contrast, for dPMC, TMS-induced deterioration of motor performance was only evident three months post-stroke, suggesting that a supportive role of contralesional premotor cortex might evolve with reorganization.ConclusionWe here highlight time-sensitive and region-specific effects of contralesional frontoparietal areas after left hemisphere stroke, which may influence on neuromodulation regimes aiming at supporting recovery of motor function post-stroke.  相似文献   
26.
原发性肾上腺皮质腺癌的CT诊断价值   总被引:13,自引:1,他引:12  
目的分析原发性肾上腺皮质腺癌(ACC)的CT表现及其动态增强特征,以提高其诊断准确性。方法回顾性分析经手术病理证实的ACC11例,术前均经CT平扫、动脉期(30S)和门静脉期(70—80S)扫描,复习CT扫描表现并和手术病理作对照。结果11例ACC中,右侧5例,左侧6例。直径4.1—16.0cm,其中,〈5.0cm者2例,5.0—10.0cm者4例,〉10.0cm5例;肿瘤境界清楚3例,邻近脂肪间隙见条索状异常密度影3例,邻近实质脏器受侵犯5例。肿瘤实质成分平扫、动脉期和门静脉期CT值分别为21.9~46.7HU(平均35.3HU)、30.5~65.8HU(平均47.1HU)和52.6~97.0HU(平均74.2HU)。肿瘤中央坏死形成假囊肿4例,网络状改变6例,实质为主伴小囊变1例;6例网络状改变者动脉期可见显著强化的不规则肿瘤血管:结论ACC具有较明显的形态学和血液动力学特征,动态增强扫描尤其是动脉期扫描有明显的诊断价值。  相似文献   
27.
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex.  相似文献   
28.
目的探讨慢性强迫游泳应激对大鼠情绪和脑细胞外信号调节激酶磷酸化(P-ERK1/2)水平的影响。方法将30只SD雄性大鼠随机分为游泳应激组、装置对照组和空白对照组,每组10只。游泳应激组每天接受5min的游泳应激,装置对照组每天接受5min的新异场景应激,均连续14 d,空白对照组不进行任何干预,然后观察大鼠行为(体质量增长量、旷场测验和糖精水溶液偏好测验)。采用免疫印迹法测定大鼠海马和前额叶皮质的P-ERK1/2。结果(1)游泳应激组在应激7d和应激14d的体质量增长[分别为(75±22)g和(70±24)g]均低于空白对照组[分别为(101±35)g和(115+47)g],均P<0.05。(2)装置对照组的粪便排泄量[(1.4±1.9)粒]多于空白对照组[(0.4±1.0)粒]和游泳应激组[(0.1±0.3)粒],均P<0.05;而游泳应激组的水平活动距离[(2077±1245)cm]少于空白对照组[(2990±1038)cm]和装置对照组[(3110±1462)cm],均P<0.05。(3)游泳应激组的糖精水溶液摄入量[(11±6)g]和糖精水溶液摄入量占总液体摄入量的比例[(37±16)%]均低于空白对照组[分别为(15±4)g和(47±15)%],均P<0.05。(4)游泳应激组在海马[(46±95)%]和前额叶皮质[(65±24)%]的P-ERK2水平均低于空白对照组[分别为(76±30)%和(99±42)%],均P<0.05。结论慢性强迫游泳应激能诱发大鼠的抑郁情绪,降低P-ERK2在海马和前额叶皮质的水平。  相似文献   
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BACKGROUND: Few data are currently available investigating neurosteroids (NS) in Alzheimer's disease (AD). The NS allopregnanolone may be decreased in serum and plasma in patients with AD, but it is unclear if allopregnanolone is also reduced in brain. Because a number of NS exhibit neuroprotective effects and impact cognitive performance in rodent models, these molecules may be relevant to the pathophysiology of neurodegenerative disorders. We therefore investigated prefrontal cortex (PFC) NS levels in AD. METHODS: Neurosteroid levels (allopregnanolone, pregnenolone, dehydroepiandrosterone [DHEA]) were determined in postmortem PFC in 14 male subjects with AD and 15 cognitively intact male control subjects by gas chromatography/mass spectrometry preceded by high-performance liquid chromatography purification. RESULTS: Subjects with AD exhibit significant reductions in allopregnanolone compared with cognitively intact control subjects (median levels = 2.50 ng/g vs. 5.59 ng/g, respectively; p = .02). Allopregnanolone levels are inversely correlated with neuropathological disease stage (Braak), r = -.49, p = .007. Median DHEA levels are elevated in subjects with AD (p = .01). CONCLUSIONS: Subjects with AD demonstrate significant reductions in PFC allopregnanolone levels, a finding that may be relevant to neuropathological disease stage severity. Neurosteroids may have utility as candidate biomarkers in AD.  相似文献   
30.
"催眠态"与"气功态"脑运动皮质低频活动差异的初步研究   总被引:3,自引:0,他引:3  
目的:研究催眠态和气功态下脑运动皮质的低频同步活动,探讨催眠态与气功态对脑功能皮质活动的不同效应。材料和方法:研究对象为1例28岁的健康女性志愿者,右利手。采用气功入静和催眠诱导分别进入气功态和催眠态。研究采用GEsigna VH/i3.0T磁共振扫描机,先后进行无任务(静息态、催眠态和气功态)和运动任务的BOLD序列扫描。图像的处理先以运动任务获得的运动皮质定位作为种子对三种状态的功能图像做交互相关分析,获得脑功能连接的激活图,然后对这些激活的体素采用功率谱分析,获得相应的优势频率和能量。结果:脑功能低频连接激活体素的数量在静息态、催眠态、气功态间没有明显差异,但通过功率谱分析,催眠态主要表现为优势频率能量的升高,而气功态则主要表现为优势频率的增加。结论:气功态和催眠态下脑运动皮质的低频活动存在一定的差异,提示两种状态有通过不同的途径产生效应,但其生理基础有待于进一步研究。  相似文献   
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