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21.
In canine atrial muscles, carbachol and nicorandil hyperpolarized the resting membrane potential and shortened the action potential duration. In the presence of carbachol or nicorandil, isoproterenol further hyperpolarized the resting membrane potential and shortened the action potential duration. Isoproterenol significantly increased the plateau duration in the presence of nicorandil, but further abbreviated it in the presence of carbachol. This increase in the plateau duration by isoproterenol in the presence of nicorandil probably reflects the increase in the slow inward current.  相似文献   
22.
PURPOSE: The purpose of this study was to determine if intrathecal landiolol, a beta1-blocker, can modulate formalin-induced nociception and spinal c-Fos expression in mice, in the absence of anesthesia. METHODS: Thirty-two mice were randomly assigned to one of four groups: the control group (n = 8) received intrathecal normal saline 10 microL, while the other three groups (n = 8 for each) received intrathecal landiolol at escalating doses of 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) respectively, immediately after induction of anesthesia with isoflurane. After awakening, inflammatory pain was induced by 10 microL of 5% formalin solution injected into the dorsal surface of the right hind paw. The nociceptive behaviours including licking, biting and lifting of the injected paw were cumulatively recorded as seconds of behaviours/min during phase I (0-10 min) and phase II (10-45 min). The c-Fos protein expressions in the spinal dorsal horn were detected with immunohistochemical techniques in the control and landiolol 750 microg.kg(-1) groups. RESULTS: Compared to the control group, intrathecal injection of landiolol 750 microg.kg(-1) significantly decreased pain-related behaviours in phase I, while intrathecal landiolol 250 microg.kg(-1), 500 microg.kg(-1) and 750 microg.kg(-1) significantly decreased pain-related behaviours in phase II during the formalin test. The numbers of c-Fos immunoreactive nuclei in the L5 spinal dorsal horn were significantly lower in the landiolol 750 microg.kg(-1) group compared to the control group (landiolol 750 microg.kg(-1) 2.4 +/- 1.1 vs control 9.2 +/- 3.9; P < 0.01). CONCLUSION: The present study indicates that intrathecally administered landiolol produces significant antinociceptive effects in the formalin test. Although further studies exploring the detailed mechanism are needed, these data suggest a potential role of beta1-adrenoreceptors in spinal nociceptive processing.  相似文献   
23.
Employing HPLC fluorometry, gas-liquid chromatography (GLC) and a novel enzymelinked immunosorbent assay (ELISA) based on a monoclonal antibody, 40 corn samples, each collected in 1993 from agricultural stocks for human consumption in Haimen (Jiangsu County) and Penlai (Shandong Province), high- and low-risk areas for primary liver cancer (PLC) in China, respectively, were analysed for fumonisins (FBs), aflatoxins (AFs) and trichothecenes. Levels and positive rates of FBs and deoxynivalenol (DON) were significantly higher in Haimen than in Penlai. ELISA of the 40 corn samples harvested in the two areas in 1994 revealed that FB contamination levels and rates in these areas were comparable to those observed in 1993 in Haimen. ELISA analysis of 1993 and 1994 products revealed a wide occurrence of AFB1 but the positive rates as well as levels were not significantly different between these areas. ELISA of the same sample number of corn harvested in 1995 revealed that FB contamination in Haimen was significantly higher than in Penlai. These 3-yearly surveys of corn samples (240 in total) demonstrated that corn harvested in Haimen was highly contaminated with FBs and that the contamination level, as well as positive rate in 1993 and 1995, were 10–50-fold higher than those in Penlai, suggesting FBs as a risk factor for promotion of PLC in endemic areas, along with the trichothecene DON. Co-contamination with AFs, potent hepatocarcinogens, was assumed to play an important role in the initiation of hepatocarcinogenesis.  相似文献   
24.
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.  相似文献   
25.
26.
The catalytic hydrolysis of phenyl esters in systems containing ß-cyclodextrin (ß-CD) and polyelectrolytes was investigated. Poly(methacrylic acid) was found to exhibit an inhibition effect on the hydrolysis, while poly(sodium styrenesulfonate) (NaPSS) shows a pronounced acceleration effect on the hydrolysis: the larger the molecular weight and the lower the degree of substitution, the greater is the acceleration effect. On the other hand, sodium ethylbenzenesulfonate and sodium dodecylbenzenesulfonate inhibit the reaction. The acceleration of the reaction in presence of NaPSS is attributed to the concentration of ß-CD and the substrate esters near to the chain of the macromolecule, through inclusion effects and hydrophobic interactions.  相似文献   
27.
28.
We retrospectively reviewed the records of 250 consecutive patients undergoing coronary artery bypass graft surgery (CABG) from January 1994 through January 1996 to determine the incidence of persistent postoperative neurological dysfunction after CABG and to compare normothermic and moderate hypothermic cardiopulmonary bypass (CPB). Normothermic CPB was used in 128 patients (36°–37°C) and hypothermic CPB (27°–28°C) in 122 patients. Postoperative neurological dysfunction included focal motor deficits, delayed recovery of consciousness (>24h) after surgery, and seizures within 1 week postoperatively. Persistent neurological dysfunction was diagnosed if complete resolution had not occurred within 10 days of surgery. The incidence of persistent postoperative neurological dysfunction was 4.1% in the hypothermic CPB group and 2.3% in the normothermic CPB group. There were no statistically significant differences between the two groups (P=NS). These results suggest that normothermic CPB did not increase the incidence of persistent postoperative neurological dysfunction compared to hypothermic CPB.  相似文献   
29.
A 52 year-old woman noticed general fatigue, polyarthralgia, and muscle weakness of lower extremities in October 2001. In December, she felt difficulty in walking due to muscle weakness. In January 2002, she admitted another hospital because of dyspnea on exertion and edema of lower extremities. Laboratory test revealed leukocytopenia, the elevation of creatine kinase and positive anti-U1-RNP antibodies. Her chest computed tomography (CT) showed severe interstitial pneumonia. Cardiac echogram revealed that she had pericardial effusion and pulmonary hypertension. Then she was transferred to Keio University Hospital and she was diagnosed as having mixed connective tissue disease (MCTD) manifestating myositis, interstitial pneumonia, pulmonary hypertension and pericarditis. Prednisolone (PSL) 60mg daily following to methylprednisolone (mPSL) pulse therapy was begun and her symptoms were gradually improved. In middle of February, she complained of high fever over 39.0 degrees C. Bacterial culture tests were negative and laboratory data indicated pancytopenia and a high level of serum ferritin. Bone marrow aspiration revealed hemophagocytosis in bone marrow specimens and she was diagnosed as having hemophagocytic syndrome associated with MCTD. mPSL pulse therapy was not effective and intermittent cyclophosphamide pulse therapy (IV-CY) was performed resulting in improvement of the symptoms. This case suggested the effectiveness of IV-CY therapy in patients with corticosteroid-resistant HPS associated with connective tissue diseases.  相似文献   
30.
A 66-year-old woman time of 10 days. One month after radicalmastectomy, there was local recurrence, followed by multiplepulmonary metastases, and the patient died of respiratory failure5 months after surgery. The gray-white-colored tumor measured13x12x;10 cm, and its border was well defined. The tumor wascomposed of diffusely growing round or polygonal cells withvesicular nuclei, prominent nucleoli, and ample cytoplasm containingeosinophilic inclusions. Lymph node involvement was widespread.Both vimentin and keratin were clearly demonstrated by immunohistochemicalstaining. Ultrastructural studies revealed that the MRT cellscontained cytoplasmic whorls of intermediate filaments.  相似文献   
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