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71.
Yasushi Kondoh Matsutaro Murakami Weimin Yin Shigenori Mizusawa Hiroyuki Nakamichi Ken Nagata 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1994,99(3):375-382
The distribution of functionally active monoamine oxidase type A (MAO-A) was investigated by in vivo quantitative autoradiography using [14C]clorgyline in normal, conscious rat brain. [14C]clorgyline was synthesized by the methylation reaction of N-desmethylclorgyline using [14C]methyliodide. Sixty minutes after [14C]clorgyline administration (1.58 MBq/animal i.v.), the brains were removed and prepared for autoradiography by washing the brain sections with 5% trichloroacetic acid solution to remove the nonbinding free tracer. The amount of MAO-A was calculated from the regional acid-insoluble tissue radioactivity and the specific activity of the tracer. The highest amount of MAO-A (5.84 nmol/g tissue) was found in the locus coeruleus. The interpeduncular nucleus, habenular nucleus, fasciculus retroflexus, and solitary tract nucleus possessed over 1.6 nmol/g tissue of MAO-A. Among 23 regions of interest, the lowest amount of MAO-A (0.37 nmol/g tissue) was found in the globus pallidus. The findings of this study suggest that the pattern of MAO-A parallels both in neuroanatomical distribution and in density that of norepinephrine and serotonin innervation. The MAO-A concentration was, however, relatively low in the dopamine-related areas. This corresponded to the previous results obtained by histochemical analysis. In addition, among the white matter structures, a high amount of MAO-A was found specifically in the fasciculus retroflexus. 相似文献
72.
目的研究不同给药方式对实体肿瘤抗癌药物疗效的影响,并通过动物实验验证。方法分别建立体内药代动力学和肿瘤内药物输运的集中参数模型,模拟单次快速注射和等时间间隔三次快速注射时肿瘤间质组织药物浓度Ct随时间的变化。实验小鼠分为两组,分别进行抗癌药羟基喜树碱(HCPT)单次快速注射和等时间间隔3次快速注射,观察其肿瘤内药物平均浓度。对数值模拟结果和动物实验结果进行比较。结果数值模拟结果显示,对于相同总量药物,等量等间隔的三次给药,肿瘤间质组织药物浓度Ct高于单次给药。动物实验的实测结果相同。结论3次给药的效果显著优于单次给药。集中参数模型基本能够定量反映不同给药方式的效果。 相似文献
73.
N. A. Ebraheim J. Lu Y. Hao A. Biyani R. A. Yeasting 《Surgical and radiologic anatomy : SRA》1998,20(4):259-262
The anterior tibial artery (ATA) is at risk of injury during high tibial osteotomy, Ilizarov wire placement, pin placement in external fixation, or proximal locking screw insertion, as the artery is not visualized intraoperatively. The ATA is anchored to the oval foramen of the interosseous membrane on the proximal tibia by the deep fascia and recurrent genicular vascular branches. Segment 1 (from the bifurcation of the popliteal artery to the level of the interosseous foramen) and the proximal part of segment 2 (from the interosseous foramen to the level where the artery crosses the anterior border of the tibia) may be damaged when pin, wire or screw placement is directed posterolaterally at that level. Distally, a straight mediolateral pin or Ilizarov wires may lacerate the artery. Segment 2 of the ATA descends against the interosseous membrane in its proximal part, which is projected on the posterior third of the tibia relative to the sagittal plane; in its middle part, it runs close to the lateral cortex of the tibia, it is projected on the middle third of the tibia; in its distal part it runs gradually towards the anterior third of the tibia and contacts with the anterior third of the tibial cortical surface. This information may help reduce risk of injury to the ATA during high tibial osteotomy, external fixation and pin placement or insertion of locking screws. 相似文献
74.
Jack M. Rogers Masahiro Usui Bruce H. KenKnight Raymond E. Ideker William M. Smith 《Annals of biomedical engineering》1997,25(5):761-768
We have developed a method for quantifying the complexity of activation patterns observed during ventricular fibrillation
(VF) that is based on our previously reported methodology for decomposing epicardial mapping data into a set of isolated wavefronts.
One-half second datasets are acquired from a 21×24 array of unipolar electrodes (1 mm spacing), and the wavefronts are isolated.
A correlation technique is used to compute the similarity between all possible pairs of the isolated wavefronts. From these
data, the wavefronts are sorted into clusters, each of which represents a recurring wavefront morphology. We define multiplicity
(M) as the number of clusters needed to account for 90% of the total activations in the VF episode.M measures the complexity of the rhythm. In repetitive patterns (e.g., sinus rhythm),M=1, indicating that the same morphology repeatedly activates the mapped region. Typically, in VF,M>1, with larger numbers representing more complex, disorganized patterns. As an example, we computedM at 5, 10, 15, and 20 sec after electrical induction of VF in six pigs.M decreased significantly (p<0.001), suggesting increasing organization during this period. 相似文献
75.
目的开发定量分析唾液腺功能及其图象显示的程序。方法应用Aladdin语言编写ROI模块提取各唾液腺及甲状腺区域的摄取数据及本底,用曲线函数生成各ROI的时间-放射性活度曲线,对曲线数据处理,计算唾液腺摄取、排泌指数等指标,然后把图象、曲线及计算结果显示在一个模板内。结果同一幅输出界面图可显示唾液腺的形态、ROI示意图、唾液腺的摄取与排泌功能数值及其曲线,以标准化的显示格式提供给临床医师。不同操作者处理同一资料的功能指标结果基本一致,软件计算的功能指数与图象显示结果及临床诊断基本相符。结论开发的唾液腺功能定量分析软件,程序运行稳定,结果重复性好。 相似文献
76.
Chain JL Joachims ML Hooker SW Laurent AB Knott-Craig CK Thompson LF 《Journal of immunological methods》2005,300(1-2):12-23
Analyzing the status of T-cell receptor (TCR) gene rearrangements has been an essential part of deciphering the stages of thymocyte development, understanding the β vs. γδ lineage decision, and characterizing T-cell leukemias. Methods such as PCR and quantitative Southern blotting provide useful information, but also have significant shortcomings such as lack of quantitation in the case of PCR and technical challenges in the case of Southern blotting. Here we describe a real-time PCR method that overcomes many of these shortcomings. This new method shows comparable results for the fraction of unrearranged TCRγ and TCRβ genes in human thymocytes and peripheral blood T cells as Southern blotting, and has the advantages of being simple to perform, highly quantitative, and requiring nanogram quantities of DNA. We also describe a real-time PCR method to quantitate T-cell receptor excision circles formed during TCRβ rearrangements. 相似文献
77.
应用模糊极小极大神经网络研究了化合物复杂结构和性能(QSAR)之间的关系,用该法进行几组化合物致癌的识别,结果优于线性回归的方法,对此作出一些分析。 相似文献
78.
目的初步探讨病毒性肝炎患者的红细胞分布宽度(RDW)、平均红细胞体积(MCV)、平均血小板体积(MPV)、血小板分布宽度(PDW)等四项血常规参数在肝纤维化诊断中的意义。方法303例病毒性肝炎患者分为急性肝炎(AH)组、慢性肝炎(CH)组、肝炎肝硬化(LC)组和重型肝炎(SH)组,对照组由16名健康人组成。采用全自动血细胞计麴仪检测所有被测试者的血常规参数,并同期对其中179例患者采用放射免疫法检测其血清透明质酸(HA)和层粘蛋白(LN)水平、采用彩色多普勒超声仪测量其脾脏的长径(SPL)及厚度(SPT),研究上述指标之间的相互关系。结果CH组、LC组和SH组患者的RDW均显著高于对照组,CH组、LC组的MCV显著高于对照组,MPV和PDW在各病毒性肝炎组与对照组之间无显著性差异:病毒性肝炎患者的RDW与其HA、LN、SPT、SPL成显著直线正相关。结论RDW对慢性肝炎肝纤维化的诊断有一定的临床价值。 相似文献
79.
目的 探讨各种阈值校正方法对统计参数图(SPM)软件统计比较结果显示的影响.方法 利用Hoffman标准脑模型制作缺损模型PET成像与正常模型PET成像,进行统计参数图的统计比较.并选取脑梗死患者与健康检查者进行统计参数图的统计比较.结果 校正与非校正产生的结果有差异,其中族错误率(FWE)校正(P=5×10-2)得到的统计分析结果激活区最少及最小,其次是错误发现率(FDR)校正(P=5×10-2),非校正方式(P=1×10-3)得到的激活区最多及最大.但FDR校正效果不稳定,有时不如不校正.结论 统计参数图软件中FWE校正方法可明显降低假阳性,得到的结果可信度稳定地高于非校正方法. 相似文献
80.
M. Canonaco L. H. O'Connor D. W. Pfaff B. S. McEwen 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1989,75(3):644-652
Summary The levels of gamma amino butyric acid (GABAA) receptors (i.e. 3H-Muscimol binding sites) were determined by quantitative neurotransmitter receptors autoradiography in ovariectomized (OVX), OVX-estradiolo (E), OVX-progesterone (P), OVX-E+P, diazepam (DZ) and DZ + Ro15-1788 treated female hamsters.The various hormonal treatments altered 3H muscimol binding in many brain areas, whereas DZ and DZ + Ro15-1788 had little influence on GABAA receptor levels at the onset of the blocked aggressive behavioral activity. For example, E, P and E+P all significantly increased 3H muscimol binding in medial preoptic area, ventromedial hypothalamic nuclei, and vertical diagonal bandmedial septal nucleus, whereas P treatment increased binding in the caudate-putamen and decreased it in reuniens nucleus of the thalamus. E and E+P treatments increased 3H muscimol binding in the corticomedial amygdala nucleus and hippocampus. Diazepam treatment decreased the GABAA receptor binding in the caudate-putamen and basolateral amygdala, while having no effect in the other brain regions where hormone treatment was effective. In vitro incubation of brain sections with micromolar concentrations of E or P did not change muscimol binding. These results suggest that ovarian steroids, and benzodiazepines to a lesser extent, modulate 3H muscimol binding but do so in different brain regions. The hormone effects on 3H muscimol binding in the critical reproductive centres at a time period that coincides with the onset of its behavioral effect is consistent with a genomic controlled activity. 相似文献