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81.
Immunohistochemistry was performed to demonstrate the cellular distribution of N-methyl-D-aspartate (NMDA) receptor subunit NMDAR1 in the intrastriatal grafts of a rat model of Parkinson's disease. Unilateral 6-hydroxydopamine (6-OHDA) lesions of the mesostriatal pathway were produced in young adult female rats. Neural transplantation was performed with fetal ventral mesencephalon (VM) tissue (at embryonic day 15) 3 weeks after the 6-OHDA lesions. In the fetal VM in which the tyrosine hydroxylase (TH) immunoreactivity was intensely observed, no NMDAR1 subunit immunoreactivity was detected. Immunopositive cells of NMDAR1 were densely distributed in the intact SNc contralateral to the lesions, in which intense immunoreactivity for TH was observed. In contrast, the cells positive for NMDAR1 in the SNr were scattered. The immunoreactivity for NMDAR1 was markedly decreased in the SNc, but not in the SNr on the lesioned side. Double immunostaining revealed that most TH-positive cells in the SNc showed moderate NMDAR1 immunoreactivity. Within the intrastriatal fetal VM grafts containing TH-positive cells, NMDAR1-positive cells tended to locate homogeneously within the grafts. These were composed of various cell sizes and shapes, but they were mainly medium-sized and aspiny cells. Double immunostaining revealed that a part of the TH-positive cells in the grafts was also immunopositive for NMDAR1. Taken together with our previous studies, it is suggested that both dopaminergic neurons and nondopaminergic neurons in the VM transplants appear to be modified functionally by glutamatergic afferents via various glutamate receptors, including NMDAR1. 相似文献
82.
目的:探讨 C A15 - 3 对术后乳腺癌的随诊价值。材料与方法:1996 年6 月至1996 年12 月行常规放疗的术后乳腺癌患者45 例,于放疗前开始首次检测外周血 C A15 - 3 值,在以后的随诊工作中,作为检查项目之一,即每1~3 个月查血1 次,监测时间为2 年。结果:有复发转移与无复发转移两组的 C A15 - 3 水平分别为(56 .21 ±8 .37) U/ml,(13 .49 ±2 .22) U/ml, P< 0 .01 ; C A15 - 3 升高的5 例复发转移患者, C A15 - 3 首次升高均出现于临床或影像学检查之前,提早时间平均为(2 .54 ±1 .36) 个月;以 C A15 - 3 > 30 U/ ml 为阳性,6 例复发、转移患者中,5 例阳性,阳性率的95 % 可信区间为36 % ~100 % ,39 例无复发、转移患者中,1 例 C A15 - 3 阳性,假阳性率的95 % 可信区间为0 ~14 % 。结论: C A15 - 3 对乳腺癌术后的转移或复发有较好的特异性和阳性预测性,在术后随诊中有不可替代的预测作用。 相似文献
83.
Serum carcinoembryonic antigens (CEA), CA 15-3, and tissue polypeptide antigens (TPA) have been used in monitoring the clinical course of patients with breast cancer. However, recent reports have suggested that the serial levels of these markers during therapy do not always correlate with the response to therapy. To clarify the usefulness of the serial combination assay of these markers in monitoring the clinical course of patients during therapy, we investigated the relationship between the initial changes and the kinetic patterns of the markers after therapy and the objective responses. When an increase or decrease of over 20% in these markers is taken to be significant, then the initial changes in all three markers significantly correlated with the therapeutic responses (P<0.01). Five distinct kinetic patterns in the marker levels were observed. A paradoxical kinetic pattern of CEA and CA 15-3 levels — that is, an initial surge and subsequent drop — was seen in one-third of the responders. The TPA levels tended to exhibit a steady decline pattern in those responders. The sensitivity and specificity of the kinetic patterns to predict the clinical courses were significantly higher than those obtained from the analysis of initial changes. These findings thus suggest that adequate knowledge of the unique kinetics of each marker may help to make a more accurate prediction of the therapeutic responses. 相似文献
84.
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86.
Else Müller-Schweinitzer 《Naunyn-Schmiedeberg's archives of pharmacology》1983,324(1):64-69
Summary The influence of the calcium antagonist nifedipine on 1- and 1-adrenoceptor vasoconstrictor effects was investigated in vitro. Changes in tension were monitored isometrically on helical strips of canine circumflex coronary and saphenous arteries suspended in 10 ml organ baths and of saphenous veins superfused with Krebs-Henseleit solution. Distinction between 1- and 2-adrenoceptor was made by using selective -adrenoceptor blocking drugs such as rauwolscine, yohimbine, corynanthine and prazosin, and the agonists noradrenaline, phenylephrine and guanfacine. In venous and both arterial vascular smooth muscles, the contractile process could be triggered by stimulation of both 1- and 2-like adrenoceptors. Nifedipine inhibited the venoconstrictor response to the 2-agonist guanfacine, leaving that to the 1-agonist phenylephrine unchanged. In saphenous arteries, nifedipine in addition to guanfacine also antagonized constrictor responses to phenylephrine, though to a significantly weaker extent. In circumflex coronary arteries, nifedipine was equally potent in antagonizing responses to both 1- and 2-adrenoceptor stimulation.It is suggested that the susceptibility of -adrenoceptormediated vasoconstrictor effects to blockade by calcium antagonists depends not only on the subtype of -adrenoceptor but, in addition, on the type and origin of vascular smooth muscle and may be a reflection of tissue variations in intracellular calcium stores. 相似文献
87.
A novel method of preparing small-sized microcapsules using a Turbotak air-atomizer is reported. Alginate-polylysine microcapsules containing Bacillus Calmette Guérin vaccine have been prepared by an adaptation of the method of Lim (1) which allows the manufacture of small-sized microcapsules. A Turbotak is used to spray sodium alginate solution into calcium chloride solution to form temporary calcium alginate microgel capsules. These temporary microgel droplets are subsequently cross-linked with polylysine to form permanent membranes. Microcapules in the size range of 5–15 µm have been produced which can be compared to an average diameter of 300 µm obtained by the method reported by Lim. The microcapsule size is dependent on the conditions of operation of the Turbotak and the concentration of the sodium alginate solution. Particles within the size range 5–15 µm can be reproducibly manufactured using the conditions of operation reported here. Other size ranges below the minimum of 300 µm reported by Lim are also feasible using this technique. 相似文献
88.
Thierry Humbert Cuong Luu-Duc Michel Comet Pierre Demenge 《European journal of nuclear medicine and molecular imaging》1991,18(11):870-878
Previous studies led us to hypothesize that a fatty acid analogue, 15-p-iodophenyl--methyl pentadecanoic acid (IMPPA or BMIPP), which is taken up but not quickly metabolized by heart cells, would be a more suitable tracer of cellular viability than thallium-201. Biodistribution studies of 1-14C-IMPPA in conscious, freely moving rats showed that the concentration ratio of radioactivity in the heart with respect to the blood was about 8 for at least 60 min after intravenous administration, permitting its use as a putative tracer in these conscious, freely moving rats. Thereafter, the myocardial uptake of14C-IMPPA was studied in isoproterenol-treated rats (daily treatment for 10 days in order to induce cardiac hypertrophy and necrotic foci) with respect to control ones. Comparison of myocardial localizations by quantitative autoradiography of the uptake of201Tl and14C-IMPPA with that of triphenyltetrazolium chloride (TTC) staining enabled comparative evaluation of nutritional blood flow, localization and uptake of14C-IMPPA and necrotic foci size. Distributions of14C-IMPPA and2011 T1 in control rats' hearts were homogeneous, like TTC staining. In infarcted hearts, areas of decreased14C-IMPPA uptake were nearly the same (100%±5%) as those unstained by TTC. These areas were larger than those showing a decrease in thallium uptake (about 70%±5% of the total scar size). Therefore, IMPPA seems to be a more accurate and sensitive indicator of necrosis localization compared with thallium. It may be a useful agent for assessment of myocardial viability by single photon emission tomography (SPET) imaging. 相似文献
89.
目的 探讨p16和p15基因第二外显子HapⅡ位点在成人急性髓性白血病 (AML)中的突变。方法 用甲基敏感和甲基非敏感限制性内切酶切消化基因组DNA后 ,经PCR扩增和琼脂糖电泳研究 3 1例AML中无p16/p15基因第二外显子缺失的患者中HapⅡ位点的突变情况。结果 在 3 1例成人AML样本中 ,p16E2 的 4个HapⅡ位点和p15E2 的 6个HapⅡ位点均未发生突变。结论 本研究提示p16和p15基因第二外显子中因甲基化而引起的CCGG位点的突变在成人AML患者中不是主要失活方式。 相似文献
90.
目的 :研究抑癌基因p15、Rb蛋白表达对喉鳞状细胞癌诊断、治疗及预后判断的意义。方法 :用免疫组化SABC法检测喉癌组 45例石蜡标本与对照组 15例喉部正常或增生的黏膜上皮标本的 p15、Rb蛋白表达情况。结果 :喉鳞状细胞癌组p15蛋白阳性率 (48.9%)与对照组阳性率 (10 0 .0 %)比较 ,差异有极显著性意义 (P<0 .0 1) ;喉癌组中 0~Ⅱ期 p15蛋白阳性率 (6 6 .7%)与Ⅲ~Ⅳ期阳性率 (33.3%)比较 ,差异有显著性意义 (P <0 .0 5 ) ;喉癌组Rb蛋白阳性率 (88.9%)与对照组阳性率 (93.3%)比较 ,差异无显著性意义 (P >0 .0 5 ) ;2× 2列联表 χ2 检验 ,p15、Rb蛋白表达无相关性 (P >0 .0 5 ) ;对照组中 ,p15蛋白的表达以鳞状上皮组织中远离基膜的棘层细胞、颗粒层细胞明显 ,而Rb蛋白的表达则以基底层细胞及近侧棘层细胞明显。结论 :抑癌基因 p15的表达缺失对喉鳞状细胞癌的发生、发展有一定的作用 ,p15蛋白的检测对喉鳞状细胞癌的治疗及估计预后有指导意义 ;喉鳞状细胞癌组织中 p15、Rb的蛋白表达无相关性 ;正常及增生的喉部鳞状上皮的细胞层次间 ,p15、Rb蛋白表达不一致 ,p15蛋白表达对细胞增殖有抑制作用。 相似文献