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81.
In order to elucidate the roles of hippocampal N-methyl-D-aspartate-type excitatory amino acid receptors in working and reference memory in rats, the effects of intrahippocampal injections of selective and competitive N-methyl-D-aspartate receptor antagonists such as CGS 19755 (cis-4-phosphonomethyl-2-piperidine carboxylic acid), 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid and 2-amino-5-phosphonovaleric acid on this behavior were examined with a three-panel runway task. The results were compared with the effect of the muscarinic receptor antagonist scopolamine. In the working memory task, CGS 19755 and 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid at 10 and 32 ng/side, injected bilaterally into the dorsal hippocampus before testing, produced a significant increase in the number of errors (attempts to pass through two incorrect panels of the three panel-gates at four choice points). This also occurred after the rats were given systemic injection of these drugs at 3.2 and 10 mg/kg. In the reference memory task, neither CGS 19755 nor 3-[(+-)-2-carboxypiperazin-4-yl]propyl-1-phosphonic acid affected the number of errors, whether given at doses up to 32 ng/side intrahippocampally or up to 10 mg/kg systemically. Working memory errors also increased significantly after intrahippocampal injections of d-2-amino-5-phosphonovaleric acid at 100 and 320 ng/side, but were not affected by I-2-amino-5-phosphonovaleric acid at doses up to 1 microgram/side. On the other hand, intrahippocampal scopolamine at 1.0 and 3.2 micrograms/side increased significantly working memory errors, without affecting reference memory errors.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
82.
We report the case of a 52-year-old female with middle-ear paraganglioma masquerading as a traumatic facial palsy, and describe the diagnostic steps and surgical treatment by the tympanomastoid approach.  相似文献   
83.
In a retrospective multicenter study to investigate the correlation between estrogen (ER) and/or progesterone receptors (PgR) in primary breast cancer with patient prognosis, 3118 patients with operable breast cancer (International Union Against Cancer Stages I, II, and III) were investigated from ten hospitals in Japan who underwent surgery from October 1972 to December 1982; 3089 were evaluable. The ER-positive and PgR-positive cancers were found in 56% and 34% of patients, respectively. The positivities decreased as the tumor size increased but were independent on lymph node metastasis. There were no significant differences in relapse-free survival (RFS) in relation to receptor status (median follow-up, 89 months [ER], 84 months [PgR]). However, in patients with four or more positive nodes, those with PgR-positive cancer had a longer RFS. The patients with ER-positive cancer survived significantly longer than ER-negative ones, with the greatest difference seen in those with four or more positive nodes. There was a significantly longer postrelapse survival (PRS) for patients with ER-positive cancer because of the different distribution of the major metastasis and better responses to first-line and subsequent treatments. Cox's multivariate analysis showed that overall survival but not PRS was affected by ER (and more weakly by PgR) because of the longer PRS in patients with ER-positive cancer.  相似文献   
84.
To apply Nd:YAG laser irradiation through a new sapphire tip contact laser method to catheter ablation in treatment of tachy-arrhythmias, effects of laser irradiation on ventricular myocardium were investigated in 10 mongrel dogs. Nd:YAG lase (1064nm) discharges were delivered to different sites on the endomyocardium at power of 5, 10, 15, 20 or 25w with duration of 3, 5, or 10 seconds (sec.) respectively in closed beating hearts. Histopathologically, the lesion irradiated was clearly demarcated from the normal myocardium by the construction band necrosis zone. The depth of injured myocardium was less than 2mm with 3 sec. irradiations, with 5 sec. from 1 mm to 4 mm in proportion to power increase, with 10 sec. from 3mm to 8 mm in proportion to the power from 5w to 15w and could not be measured in cases of more than 20w irradiations. Although with every irradiation duration, the depth of injury increased in proportion to the power increase. With the same total energy, a longer time of irradiation produced deeper injury than a shorter time. This method makes it easier to keep the laser positioned to target than bare laser, and is suitable for use in catheter ablation.  相似文献   
85.
86.
The effects of potassium in reperfusion solution (RS) and the influence of sodium on this effect were studied. Experimental time course was as followed: 20 min working perfusion, 3 min cardioplegic infusion with St. Thomas Cardioplegic Solution followed by global ischemia for 33 or 35 min at 37.5 degrees C, 15 min early Langendorff reperfusion with several different potassium concentration modified with Krebs Henseleit Bicarbonate Buffer (KHBB) containing 145 mM and 110 mM sodium and 5 min late reperfusion with KHBB, followed by 20 min working perfusion. Potassium in RS possessed bell shaped dose response nature with optimal concentration of 10 mM in the condition of 145 mM sodium but 6 m in the condition of 110 mM in terms of percent recovery of aortic flow. Although higher potassium reperfusion produced less Creatine Kinase leakage.  相似文献   
87.
The etiology and pathophysiology of schizophrenia and related mental disorders such as bipolar disorder and major depression remain largely unclear. Recent advances in mRNA profiling techniques made it possible to perform genome-wide gene expression analysis in a hypothesis-free manner. It was thought that this large-scale data mining approach would reveal unknown molecular cascades involved in mental disorders. Contrary to this initial expectation, however, DNA microarray results in psychiatric fields have been notoriously discordant. Here the authors review the findings of DNA microarray analysis, focusing on systematic gene expression changes in schizophrenia, as well as alterations in the expression of specific genes, that have been reported and replicated. The authors also address the probable causes for the discordance among studies, possible ways to solve the problem, and their preferred approach for data interpretation.  相似文献   
88.
89.
The three human isozymes of alkaline phosphatases were quantitatively determined in normal testis and seminoma tissues. The highly selective assays were based on isozyme specific monoclonal antibodies. In the normal testis approximately 90% of the catalytic activity originates from the tissue unspecific alkaline phosphatase, and the remaining activity was due to trace expression of both intestinal (approximately 5%) and placental alkaline phosphatase (PLAP) or PLAP-like isozyme (approximately 5%). In homogenates of seminoma tissues, highly increased levels of all three isozymes were identified. Both the tissue unspecific alkaline phosphatase and PLAP-like enzymes displayed relative increases of 10- to 100-fold and intestinal alkaline phosphatase 2- to 10-fold compared with normal testis. This finding indicates that the entire genome coding for alkaline phosphatases may be activated in seminomas. The PLAP-like enzyme from seminoma cells comprises a heterogenous population of molecules demonstrating partial heat sensitivity and microheterogeneity upon starch gel electrophoresis in contrast to the pregnancy related PLAP. These findings have implications for the different PLAP assays used in the clinical monitoring of seminoma patients.  相似文献   
90.
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