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41.
Several neurons from different nuclei give rise to descending spinal tracts and project to various levels in the spinal cord of goldfish, Carassius auratus. These were visualized by retrograde transport of horseradish peroxidase (HRP) administered to the bilaterally transected spinal cord at 6 levels, corresponding to 1st, 5th, 10th, 15th, 20th and 25gh segments of the vertebral column. As many as 16 brain nuclei or neuronal aggregations and the Mauthner cells project posteriorly up to the 20th spinal segment. Restricted neurons of the dorsolateral area in the nucleus preopticus magnocellularis and those of the ventromedial nucleus of the thalamus projected up to the 20th and 25th segments respectively. In the mesencephalon, the nucleus ruber and the nucleus of the medial longitudinal fasciculus revealed retrogradely labeled somata; the former extended up to the 20th segment, while the latter projected up to the 25th segment. The remaining descending projected neurons of the brain belonged to the rhombencephalon. The nucleus of the lateral lemniscus; anterior, magnocellular, descending and posterior divisions of the octaval nucleus: raphe nucleus; Mauthner cell and the neurons located adjacent to the trigeminal tract and those in the vicinity of the secondary gustatory tract sent their processes up to 20th segmental level. However, somata of the superior, medial and inferior divisions of the reticular nucleus and restricted neurons of the facial lobe extended up to 25th segmental level. The pattern of neuronal projections into the spinal cord suggests a topographic organization.  相似文献   
42.
The effects of KB-2796, 1-[bis(4-fluorophenyl)methyl]-4-(2,3,4-trimethoxybenzyl)piperazine-2HCl, on the low- and high-voltage activated Ca2+ currents (LVA and HVA ICa, respectively) and on oxidative metabolism were studied in neurons freshly dissociated from rat brain. KB-2796 reduced the peak amplitude of LVA ICa in a concentration-dependent manner with a threshold concentration of 10−7 M when the LVA ICa was elicited every 30 s in the external solution with 10 mM Ca2+. The concentration for half-maximum inhibition (IC50) was 1.9 × 10−6M. At 10−5 M or more of KB-2796, a complete suppression of the LVA ICa was observed in the majority of neurons tested. There was no apparent effect on the current-voltage (I-V) relationship and the current kinetics. KB-2796 delayed the reactivation and enhanced the inactivation of the Ca2+ channel for LVA ICa voltage- and time-dependently, suggesting that KB-2796 preferentially binds to the inactivated Ca2+ channel. KB-2796 at a concentration of3.0 × 10−6M also decreased the peak amplitude of the HVA ICa without shifting the I-V relationship. In addition, KB-2796 reduced the oxidative metabolism (the formation of reactive oxygen species) of the neuron in a concentration-dependent manner with a threshold concentration of3 × 10−6M. It is suggested that the inhibitory action of KB-2796 on the neuronal Ca2+ influx and the oxidative metabolism, in combination with a cerebral vasodilatory action, may reduce ischemic brain damage.  相似文献   
43.
Geste antagonistes, or sensory tricks, are well described in focal dystonia affecting the neck, hand, and face. Improvement in dystonic movements is typically maintained while the trick is performed, but disappears when the geste ends. We investigated the phenomenological features of geste antagoniste maneuvers in 19 patients with idiopathic lower cranial dystonia who were prospectively evaluated over a period of 6 years. Of the 19, 10 were men, mean age of onset was 49.8 years, and the most commonly involved lower cranial area was the jaw (10 patients). In most patients, dystonia was task-specific. Taking advantage of the improvement with a sensory geste, we manufactured oral appliances that mimicked the geste in 8 patients, and 3 continue to use it.  相似文献   
44.
SA、F/TPSA及PSAD在前列腺癌诊断中的作用   总被引:1,自引:0,他引:1  
目的 :探讨血清前列腺特异抗原 (PSA) ,血清总PSA及游离PSA比值 (F/TPSA)及前列腺特异性抗原密度(PSAD)在前列腺癌诊断中的作用。方法 :对 5 1例前列腺癌患者及 14 5例良性前列腺增生症患者PSA、F/TPSA及PSAD值的差异进行分析、比较。结果 :前列腺癌组血清PSA及PSAD高于良性前列腺增生组 ;而F/TPSA值低于良性前列腺增生组 ,差异均有显著性。结论 :PSA >4ng·ml-1作为筛选前列腺癌的临界值存在一定缺陷 ;当PSA <10ng·ml-1,F/T值有助于鉴别前列腺癌和良性前列腺增生 ;而PSAD对于筛选前列腺活检病例亦有一定价值。  相似文献   
45.
46.
BACKGROUND: Little is known about time trends of allergic respiratory disease in adults, in particular in older adults. Furthermore, few trend studies have used objective measurements of IgE sensitization against inhalant allergens. OBJECTIVES: To investigate time trends of aeroallergen sensitization in adults over a 25-year period. METHODS: The study includes a total of 7820 persons, aged 30, 40, 50, and 60 years, who participated in three repeated cross-sectional studies of the general population of Copenhagen, Denmark, in 1976-1977, 1982-1984, and 1999-2001, respectively. Respiratory allergy was assessed by determination of specific IgE aeroallergen sensitization in stored serum samples. RESULTS: Over this 25-year period, a marked and statistically significant increase in the prevalence of aeroallergen sensitization had occurred. This increase was seen in all age-groups challenging the notion that the allergy epidemic only affects generations born 1960 onwards. For example, in 40-year-olds the prevalence (with 95% confidence intervals) of aeroallergen sensitization was 14.9% (12.7-17.1), 19.7% (17.1-22.3), and 27.6% (25.1-30.1) in 1976-1977, 1982-1984, and 1999-2001, respectively. CONCLUSIONS: Our results support that the allergy epidemic has spread to older adults resulting in a continuing increase in the overall prevalence of aeroallergen sensitization and an increase in the mean age of allergic patients.  相似文献   
47.
microRNAs(miRNAs)是一类分布十分广泛的内源性非编码RNA,在动物、植物、病毒中广泛存在。miRNAs与肿瘤的发生发展预后有关,并在肿瘤的增殖、分化及调亡等方面有重要的作用。结合最近相关文献,本文就miRNAs与泌尿系肿瘤方面的进展作简要概述。  相似文献   
48.
近交系胎鼠中脑多巴胺能神经元体外定向分化的初步研究   总被引:1,自引:0,他引:1  
目的体外培养近交系大鼠胚胎腹侧中脑前体细胞(VMP)并诱导其分化为多巴胺能神经元(DN),为研究DN定向分化的分子机制提供细胞模型。方法取材胎龄11d的近交系大鼠胚胎VMP,体外用碱性成纤维细胞生长因子(bFGF)增殖培养7d后换用L-抗坏血酸-2-磷酸酯倍半镁盐(AA-2P)诱导分化为DN,随后进行免疫荧光染色鉴定。结果细胞总数扩增49.76倍,免疫荧光染色显示β-TubulinⅢ阳性的神经元中(71.33±20.42)%为TH阳性的DN,后者占细胞总数的(24.85±12.85)%。结论近交系大鼠VMP经体外原代培养能够得到较高比例的DN,可作为深入研究DN定向分化分子机制的细胞模型。  相似文献   
49.
目的:探讨不同类型神经保护剂联合应用即鸡尾酒(cocktail)疗法是否较单一神经保护剂对海马神经元培养氧糖剥离(OGD)后有更好的保护作用。方法:采用海马神经元培养氧糖剥离(OGD)模型,分为1,6-二磷酸果糖(FDP)组、MK-801组、N-乙酰半胱氨酸(NAC)组、cocktail组和对照组,观察神经元凋亡及抗凋亡蛋白Bcl-2表达情况。结果:cocktail组神经元凋亡减少,Bcl-2表达增多,与单-用药各组相比有显著性差异(P<0.05)。结论:神经保护剂cocktail疗法对神经元缺血保护作用较单一用药明显增强。  相似文献   
50.
目的 比较大脑皮质向脊髓与红核发出投射的区域并探讨是否有分支投射存在。方法 将。TB及NY分别注入大白鼠的脊髓与红核内,在大脑皮质观察比较标记细胞出现的部位。结果 FB标记细胞出现在24,10,8,6,4,3,1,2,23,29b,29c,18,7,13,39区。NY标记细胞出现于6,4,3,1区,10区的尾侧部及7,18区的颅饲部亦有少量存在。无发现双标记细胞。结论 大脑皮质向脊髓发出投射的区域非常广泛,向红核发出投射的区域全部重叠于皮质脊髓神经元分布的区域内,皮质脊髓神经元无分支投射到红核。  相似文献   
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