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91.
TheEffectsofAstragalusmembranaceusandTripterygiumhypoglaucumonNKActivityinSystemicLupusErythematosusZhaoXiao-zhong(赵小忠)(Depar...  相似文献   
92.
Summary The influence of locomotor activity upon neurons in the lateral vestibular nucleus was investigated in precollicularly-postmamillary decerebrate guinea pigs. Out of 95 recorded neurons, 24 were identified as vestibulospinal and 71 had no descending projections. Locomotor activity occurred either spontaneously or was prompted by electrical stimulation of the mesencephalic locomotor region. Natural vestibular stimulation was supplied by tilting the animal about its longitudinal axis. Locomotor rhythmic limb muscle activity was accompanied by an increase in the firing frequency in the vast majority of investigated neurons. The increase in frequency was observed at the beginning of ipsilateral forelimb extensor muscle activity. Only in a few non-vestibulospinal neurons was the spontaneous activity depressed during locomotion. An increase in evoked responses was observed in almost all vestibulospinal neurons and in two thirds of the neurons without descending projections. A decrease in evoked responses was observed in one quarter of non-vestibulospinal neurons. During locomotion, the mean and maximal frequencies of evoked neuronal impulse activity changed, but the phase lag of these changes was not altered significantly. The results suggest an enhancement of vestibulospinal influences during locomotion, thus providing a high level of tonus in antigravitational muscles. This is interpreted as a mechanism to ensure that equilibrium is maintained during motion in different gaits and postures.  相似文献   
93.
Summary Levels of soluble IL-2 receptors, IL-6, soluble CD23, soluble CD14 and ECP (eosinophilic cationic protein) were measured as markers of T-cell, B-cell, monocyte and eosinophilic leucocyte activation in 26 patients with atopic dermatitis (AD) on admission to (A) and at discharge from (D) the Department of Dermatology in Zurich. The serum levels of sIL-2R, IL-6, sCD23, sCD14 and ECP were significantly elevated in AD patients in comparison with the normal values of healthy donors. A significant decrease in sIL-2R (p=0.0093) and in sCD14 (p=0.0134) levels was demonstrated between A and D, correlating with the improvement in the skin intensity score (SIS). In addition, a significant correlation of the sCD14 levels and the SIS at A was demonstrated (p=0.0415). These results also incriminate monocytes in the pathogenesis of AD, indicating that, besides sIL-2R and ECP, SCD14 could also be a possible marker for the disease activity.  相似文献   
94.
L  zl  L  n  rd  Yutaka Oomura  Yasuhiko Nakano  Shuji Aou  Hitoo Nishino 《Brain research》1989,500(1-2):359-368
Single neuron activity in the monkey amygdala was investigated during cue signalled conditioned bar press feeding behavior and the effects of electrophoretically applied acetylcholine (ACh) and atropine were analyzed. ACh increased the firing rate of one third of the neurons tested; these excitatory responses were inhibited by the muscarinic receptor antagonist atropine. No characteristic location of ACh-sensitive neurons was found, cells were diffusely distributed throughout the amygdala. Activity of ACh-sensitive neurons did not correlate with any particular event during the bar press feeding task. However, continuous application of ACh at low current intensity during the task significantly enhanced the task-related excitatory firing patterns, or markedly attenuated the inhibitory responses. Continuous application of atropine elicited or enhanced inhibitory response patterns. These results suggest that the cholinergic system of the monkey amygdala facilitates neuronal excitation but attenuates inhibition related to various phases of feeding behavior, such as to cue recognition, food aquisition and rewarding process.  相似文献   
95.
ABSTRACT A follow-up examination was performed one month to 20 years after adrenalectomy in 28 cases with surgically treated primary aldosteronism due to adrenal adenoma. The mean age at diagnosis was 45, and the mean duration of hypertension seven years. Severe hypertension with a diastolic blood pressure of 130 mmHg or more was observed in 35%. Postoperatively cerebrovascular catastrophe developed in two cases, both of which belonged to the group of patients with severe hypertension. Normalization of blood pressure was observed in 70% and in the remaining subjects the blood pressure was lower than at diagnosis. The blood pressure response to adrenalectomy appeared unpredictable in view of such parameters as the initial blood pressure, age at diagnosis, and duration of the hypertensive state. Toxicosis during pregnancy and metrorrhagia was observed with unexpectedly high frequency in this study population. Low ambulatory plasma renin activity was recorded at the follow-up in 15 out of 18 subjects studied in the absence of evidence of hyperaldosteronism.  相似文献   
96.
银染端粒重复序列扩增法定量检测端粒酶活性的研究   总被引:1,自引:0,他引:1  
目的:探讨运用简便、快速及无放射性污染的银染粒重复序列扩增法(silver staining telomeric repeat amplification protocol,SS-TRAP)定量检测端粒酶活性。方法:运用SS-TRAP法检测了293细胞、经加热处理的293细胞、空白对照及典型乳腺癌组织、良性乳腺病变标本中端粒酶活性,其结果予以定量。结果:该法有检测出10个以上293细胞中端粒酶活性,热处理及空白对照均为阴性;乳癌组织标本中银染条带清晰可见,而良性病变中未见端粒酶阳性条带。结论:非核素银染TRAP法可用于端粒酶活性定量检测,与TRAP法相比,同样具有较高敏感性和特异性,但更快速、简便。  相似文献   
97.
目的探讨导管射频消融(RFCA)在治疗飞行员多种快速性心律失常中的安全性及临床应用价值,探讨飞行员快速性心律失常的航空医学鉴定标准。方法对13例快速性心律失常的飞行员进行了电生理(EP)检查,特发性室性心动过速(VT)1例,频发室性期前收缩(VE)2例,阵发性心房纤颤(AF)1例,房室折返性心动过速(AVRT)5例,房室结折返性心动过速(AVNRT)3例,房性心动过速(AT)1例。对其中12例采用RFCA治疗。结果RFCA即刻成功率为100%,全组无并发症发生。1例房性心动过速未行导管射频消融治疗。所有飞行员术后地面观察6个月后,返院进行随访复查,同时进行飞行鉴定。12例导管射频消融治疗,术后6个月24h动态心电图、12导联心电图检查和食道电生理检查均未检测到术前的同型快速性心律失常发作,延迟成功率为100%,医学鉴定合格。1例AT仍有发作,飞行不合格。结论对于飞行员快速性心律失常进行导管射频消融治疗是一种安全、有效的治疗方法。心脏电生理检查应作为飞行员快速性心律失常医学鉴定的主要指标之一。  相似文献   
98.
对一株曲霉果糖转移酶菌株的产酶培养条件进行了研究。确定了最佳培养基组成:初始蔗糖质量浓度15~18g/dL,氮源为酵母膏,K2HPO4对果糖转移酶的产生具有明显的促进作用,添加0.2g/dLCMC能够使果糖转移酶活力提高到原来的1.3倍,在pH5.5,30℃条件下,果糖转移酶最高酶活力为30.42U/mL。HPLC分析结果表明,转糖基产物为总质量的55.8%。  相似文献   
99.
为筛选大叶紫薇叶中具有降血糖活性的成分,采用3T3-L1细胞葡萄糖消耗模型作为检测手段,对大叶紫薇叶提取物采用HP-20树脂吸附、溶剂萃取、制备薄层分离和制备高效液相分离,导向筛选具有降血糖作用的各分离组分.结果发现,大叶紫薇叶中corosolic acid、熊果酸和总三萜具有降血糖活性.  相似文献   
100.
采用HS-SPME与GC—MS结合的方法,通过对戊糖的4种立体异构物(核糖、木糖、阿拉伯糖、来苏糖)与半胱氨酸Maillard反应挥发性产物的分析,确定了部分挥发物的相对质量分数,并对其随反应时间的变化情况进行了比较分析,进而推测戊糖的结构与反应活性的关系。0.4mol/L等摩尔浓度的戊糖与L-半胱氨酸在磷酸盐缓冲液中,120℃,反应40min时,核糖产生的挥发性产物量远高于其他3种戊糖,说明其反应活性最高;当反应时间达到3h后,4种戊糖的挥发性产物量趋同。  相似文献   
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