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51.
In our previous studies, we hypothesized that activation and subsequent collapse of GABA-mediated inhibition during tetanus is an important seizure-triggering mechanism in the kindled epileptogenic focus. To examine this hypothesis, in the present study, we investigated the effects of pharmacological manipulations of the kindled amygdala with several drugs, and measured the kindled seizures as well as the EEG events during tetanus. The results obtained were: (i) The selective GABA-A agonist, muscimol (1 and 5 nM/1 microliter), suppressed kindled seizures in a dose-dependent fashion, and the 5 nM muscimol significantly prolonged EEG suppression and reduced the number of oscillations in the subsequent rhythmic synchronous discharge. Similar effects followed systemic injection of diazepam (2 mg/kg). (ii) The selective GABA-B agonist, baclofen (5 nM), had no effect on kindled seizures nor on the EEG events during tetanus. (iii) The NMDA antagonist, 2-amino-5-phosphonovaleric acid (80 nM), significantly reduced the afterdischarge duration and significantly delayed the appearance of the rhythmic synchronous discharge. However, these effects were not observed immediately, but 24 to 72 h after microinjection. (iv) The muscarinic cholinergic antagonist, atropine (40 and 80 nM), suppressed kindled seizures in a dose-dependent fashion, but the atropine caused marked synchronous discharge both in the awake resting EEG and during tetanic stimulation. We conclude that the GABA-A system, including the benzodiazepine system, is more involved in the seizure-triggering mechanism of amygdala kindling than the GABA-B system, that there is an interaction between the GABA-A and NMDA system, and that the cholinergic participation is independent of the primary seizure-triggering mechanisms.  相似文献   
52.
Atypical Shone''s complex is a rare congenital anomaly involving a left-sided obstructive lesion of two or three cardiovascular levels. A 70-year-old man with dyspnea on exertion was diagnosed with severe aortic stenosis (AS) with a bicuspid valve, complicated by severe aortic coarctation (CoA) and a double-orifice mitral valve. He underwent surgery for AS and CoA in one session. It is important to search for complicated malformations, even in cases of bicuspid aortic valve found in old age.  相似文献   
53.

Objective

To determine the value of using the Roter Interaction Analysis System during objective structured clinical examinations (OSCEs) to assess pharmacy students'' communication competence.

Methods

As pharmacy students completed a clinical OSCE involving an interview with a simulated patient, 3 experts used a global rating scale to assess students'' overall performance in the interview, and both the student''s and patient''s languages were coded using the Roter Interaction Analysis System (RIAS). The coders recorded the number of utterances (ie, units of spoken language) in each RIAS category. Correlations between the raters'' scores and the number and types of utterances were examined.

Results

There was a significant correlation between students'' global rating scores on the OSCE and the number of utterances in the RIAS socio-emotional category but not the RIAS business category.

Conclusions

The RIAS proved to be a useful tool for assessing the socio-emotional aspect of students'' interview skills.  相似文献   
54.
PURPOSE: Nitroglycerin may improve the response to chemotherapy in advanced non-small cell lung cancer. The effects and mechanisms of nitroglycerin on the enhancement of chemosensitivity to docetaxel and carboplatin regimen (DCb) in patients with lung adenocarcinoma have not been reported. EXPERIMENTAL DESIGN: Seventeen patients with operable lung adenocarcinoma and stable angina pectoris were selected to investigate the effects of nitroglycerin on immunoreactivity for hypoxia-inducible factor 1alpha (HIF-1alpha), vascular endothelial growth factor (VEGF), P-glycoprotein (P-gp), the production of which is regulated by HIF-1, and p53 proteins in their resected tumor by semiquantitative immunohistochemical analyses. Eight of 17 patients were treated with nitroglycerin patches before operation, but 9 of 17 patients were not. Furthermore, to study the relationship between changes in plasma VEGF levels by nitroglycerin treatment and response to DCb, 29 patients with advanced lung adenocarcinoma were treated with nitroglycerin for 3 days before chemotherapy using DCb. RESULTS: The rates of immunoreactive cells for HIF-1alpha, VEGF, and P-gp in tumor tissues treated with nitroglycerin were lower than those without nitroglycerin, but those for p53 were not different between those treated with and without nitroglycerin. Furthermore, the rates of immunoreactive cells for VEGF and P-gp proteins were significantly associated with those for HIF-1alpha in tumor tissue. The magnitude of decrease in plasma VEGF levels after treatment with nitroglycerin was significantly associated with response to DCb in patients with advanced lung adenocarcinoma. CONCLUSIONS: Nitroglycerin treatment may improve response to DCb in patients with lung adenocarcinoma, partly through decreasing VEGF and P-gp production via reduction of HIF-1alpha.  相似文献   
55.
7-ethyl-10-[4-(1-piperidyl)-1-piperidyl] carbonyloxy-camptothecin, a topoisomerase I (topo I) inhibitor, is one of the most active agent against lung cancer, and its radiosensitizing effect has been reported recently. We evaluated a combination in vitro effect of irradiation and 7-ethyl-10-hydroxy-CPT (SN-38), an active metabolite of 7-ethyl-10-[4- (1-piperidyl)-1-piperidyl] carbonyloxy-camptothecin, on a human small cell lung cancer cell line (SBC-3) and its cisplatin-resistant subline (SBC-3/CDDP). Growth-inhibitory effects of irradiation with or without SN-38 were determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. A modified isobologram method was used to evaluate the treatment interaction. The combination of irradiation and SN-38 showed a synergistic inhibitory effect on the growth of SBC-3/CDDP despite its cross-resistance to irradiation and SN-38. In contrast, the same combination showed only an additive effect on the growth of parental SBC-3 cells. There was no significant difference in topo I protein expression between these two cell lines. In SBC-3 cells, topo I catalytic activity was suppressed by 4 Gy of irradiation, without a decrease of nuclear topo I protein, whereas the exposure of SBC-3 cells to 1 microM SN-38 subsequent to irradiation showed no remarkable additional effects on both topo I activity and protein content. On the other hand, in SBC-3/CDDP cells, topo I activity was unchanged by irradiation, but the subsequent exposure to SN-38 gave rise to a decrease in topo I activity, which was accompanied by a significant decrease in the topo I protein content (P = 0.02). These observations may indicate that SN-38 induces sequestration of topo I onto DNA in radiation-treated SBC-3/CDDP cells and suggest that the synergistic effect of irradiation and SN-38 in SBC-3/CDDP cells was considered attributable to DNA repair-related enhanced recruitment of topo I onto the damaged DNA.  相似文献   
56.
Histopathological diagnosis is the ultimate method of attaining the final diagnosis; however, the observation range is limited to the two‐dimensional plane, and it requires thin slicing of the tissue, which limits diagnostic information. To seek solutions for these problems, we proposed a novel imaging‐based histopathological examination. We used the multiphoton excitation microscopy (MPM) technique to establish a method for visualizing unfixed/unstained human breast tissues. Under near‐infrared ray excitation, fresh human breast tissues emitted fluorescent signals with three major peaks, which enabled visualizing the breast tissue morphology without any fixation or dye staining. Our study using human breast tissue samples from 32 patients indicated that experienced pathologists can estimate normal or cancerous lesions using only these MPM images with a kappa coefficient of 1.0. Moreover, we developed an image classification algorithm with artificial intelligence that enabled us to automatically define cancer cells in small areas with a high sensitivity of ≥0.942. Taken together, label‐free MPM imaging is a promising method for the real‐time automatic diagnosis of breast cancer.  相似文献   
57.
This study was undertaken in order to clarify the clinical characteristic features and surgical results of coronary artery bypass grafting (CABG) in patients over 65 years of age (group III, n=43). These patients were compared with 2 other groups of patients, one aged between 50 and 59 years (group I, n=88) and another aged between 60 and 64 years (group II, n=54), with respect to mortality, morbidity and late survival. CABG was performed with the saphenous vein under cold K-Mg-cardioplegia with systemic hypothermia. The hospital mortality was 2.3, 3.7, and 4.7 per cent in groups I, II and III, respectively, although no operative mortality was noted in any group. The number of coronary artery lesions increased with age, however, the left ventricular ejection fraction was relatively better preserved in the aged patient than in the younger ones. The 5-year survival rates were 93.4, 95.1 and 96.9 per cent in groups I, II and III, respectively, with most of the late deaths occurring within a year after CABG in each group. In the aged patients, postoperative functional recovery was delayed in the liver and kidney, and postoperative psychosis was not infrequent. The results of this study, indicating a low operative mortality and satisfactory late survival rate, thus strongly support CABG for the aged. Nevertheless, the prevention of postoperative complications is also extremely important for reducing hospital mortality.  相似文献   
58.
PURPOSE: Although recent advances in diagnostic imaging have allowed a number of patients with focal nodular hyperplasia (FNH) to avoid surgical treatment, the natural course of large FNH is still unknown. CASE REPORT: A 25-year-old man was admitted because of a large hepatic mass detected on routine examination in June 1998. The only laboratory abnormality was an elevated gamma-GTP. Computed tomography, angiography, positron emission tomography using F-18 fluorodeoxyglucose (FDG-PET), and scintigraphy using technetium-99m-galactosylneoglycoalbumin(99mTc-NGA) demonstrated a spoke-wheel appearance of vessels, normal hepatocytes, and no malignancy. Histologic findings on needle biopsy were consistent with FNH. After informed consent, the patient agreed to observation. Two years after the initial diagnosis, he has no symptoms, and there are no changes in the size or character of the lesion on computed tomography. DISCUSSION: Careful observation of patients with FNH is required because its natural course is unknown and these lesions can bleed or rupture.  相似文献   
59.
Thyrotropin-releasing hormone (TRH), a neuropeptide with multiple neuromodulatory functions, has been receiving examination for clinical relevance in epilepsy. To investigate the neurophysiologic properties of the anticonvulsant action of TRH, its effects on the evoked responses and long-term potentiation (LTP) of the perforant path input to the dentate gyrus were examined in anesthetized rats. Intracerebroventricular microinjected 80 micrograms TRH increased the relationship between the amplitude of the population spike and the slope of the EPSP, and reduced the LTP of the EPSP by approximately 30% compared with saline-injected controls. The TRH, however, slightly increased the amplitude of the population spike. These effects of TRH on LTP were confirmed in a dose-related manner. These results indicate that TRH may have two independent effects in the dentate gyrus, an increase in cellular excitability and a decrease in synaptic plasticity. The latter may be related to the previously reported anticonvulsant effects on kindling.  相似文献   
60.
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