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41.
Intrarenal infusion of forskolin (0.2 microgram/kg/min) in anesthetized dogs increased renal blood flow (RBF) and glomerular filtration rate (GFR) to the same degree but did not change the mean arterial pressure or heart rate. Forskolin also increased urine flow and urinary sodium excretion. The proportional increases in RBF and GFR may result from a preferential action of forskolin to dilate the afferent arteriole.  相似文献   
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Appropriately substituted benzylamine (BZA) derivatives, fragmented derivatives of tetrahydroisoquinolines, were found to be directly acting adrenergic beta-stimulants, exhibiting tracheal relaxing, positive chronotropic and free fatty acid (FFA) releasing activities. The chemical structures essential for manifestation of the beta-action were i) 3,4-dihydroxybenzylamine, ii) arylmethyl group at position alpha, iii) lower alkyl group on the N atom. The structure activity relationships of BZA-derivatives were almost similar to, but partly different from those of tetrahydroisoquinoline- and catecholamine-derivatives. The tracheal relaxing, positive chronotropic and FFA-releasing actions of alpha-(3,4,5-trimethoxybenzyl)-N-methyl-3,4-dihydroxybenzylamine, the most active compound in the BZA-derivatives tested, were approximately one-hundred, thirty and fifty times less active than those of ISO, respectively. These results indicate that this compound is beta1-selective, while trimetoquinol is beta2-selective.  相似文献   
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Understanding the molecular action of gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor, might allow us to perform more effective therapies for hormone-independent advanced prostate cancer. A DNA microarray study was undertaken to comprehensively analyze the alteration of levels of 1,081 genes after gefitinib treatment in androgen-independent PC3 and DU145 cells and androgen-dependent LNCaP cells. The proliferation of PC3, DU145 and LNCaP cells was significantly inhibited by 50.2%, 83.8% and 55.2%, respectively, 6 days after 10 microM gefitinib administration. Of the above 1,081 genes, we identified 23, 13 and 33 genes with significantly different expression in PC3, DU145 and LNCaP cells, respectively, 24 h after 10 microM-gefitinib exposure. Among the identified genes, only Quiescin Q6, a negative cell cycle regulator, was increased after gefitinib treatment in all three cell lines regardless of gefitinib sensitivity. Except for Quiescin Q6, there were no overlapping genes between PC3 and DU145 cells. However, levels of several oncogenes or proliferation-related genes were changed after gefitinib treatment in the 2 androgen-independent cell lines. We also identified 7 unique genes [glycyl-tRNA synthetase, interferon, alpha-inducible protein, stratifin, nuclear factor of kappa light polypeptide gene enhancer in B-cells 1, dual specificity phosphatase 9, guanine nucleotide binding protein (G protein) beta polypeptide 2, neural retina leucine zipper] whose levels were altered exclusively after gefitinib administration in gefitinib-resistant PC3 and LNCaP cells, but not in DU145 cells, suggesting that these 7 genes could be targets for overcoming gefitinib resistance. Collectively, our molecular profiling data will serve as a framework for understanding the molecular action of gefitinib for prostate cancer.  相似文献   
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This is the first identified case of Mycobacterium bovis bacillus Calmette-Guerin (BCG)-derived cutaneous tuberculosis that localizes at a place different from the vaccination site in hosts without immune deficiency. A healthy baby with a developing abscess is described. A multiplex PCR identified the abscess as originating from M. bovis BCG Tokyo 172.  相似文献   
48.
PURPOSE: To determine the incidence of developing an idiopathic full-thickness macular hole in fellow eyes that have vitreofoveal attachments and perifoveal vitreous detachment in patients with unilateral idiopathic macular hole. DESIGN: Retrospective cross-sectional observational study. METHODS: The fellow eyes of 201 patients with full-thickness macular holes were examined by optical coherence tomography (OCT). A subset of 58 fellow eyes with vitreofoveal attachments and perifoveal vitreous detachment was observed during follow-up, and the changes in the vitreofoveal attachment within 24 months from the initial OCT examination were investigated. RESULTS: In the 58 eyes, the vitreofoveal relationship changed in 27 eyes. Among the 27 eyes, three eyes developed a full-thickness macular hole, and the other 24 eyes developed a posterior vitreous detachment only over the fovea or a complete posterior vitreous detachment without macular hole formation. The vitreofoveal relationship did not change in 31 eyes during the 24-month period. CONCLUSION: From an analysis of the changes in the vitreoretinal relationship identified by OCT, three (11%) of 27 fellow eyes in patients with unilateral idiopathic macular hole developed a full-thickness macular hole.  相似文献   
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Studies were performed to test the hypothesis that reactive oxygen species (ROS) and mitogen-activated protein kinase (MAPK) contribute to the pathogenesis of aldosterone/salt-induced renal injury. Rats were given 1% NaCl to drink and were treated with one of the following combinations for 6 weeks: vehicle (0.5% ethanol, SC, n=6); aldosterone (0.75 microg/H, SC, n=8); aldosterone plus a selective mineralocorticoid receptor antagonist; eplerenone (0.125% in chow, n=8); aldosterone plus an antioxidant; and tempol (3 mmol/L in drinking solution, n=8). The activities of MAPKs, including extracellular signal-regulated kinases (ERK)1/2, c-Jun-NH2-terminal kinases (JNK), p38MAPK, and big-MAPK-1 (BMK1) in renal cortical tissues were measured by Western blot analysis. Aldosterone-infused rats showed higher systolic blood pressure (165+/-5 mm Hg) and urinary excretion of protein (106+/-24 mg/d) than vehicle-infused rats (118+/-3 mm Hg and 10+/-3 mg/d). Renal cortical mRNA expression of p22phox, Nox-4, and gp91phox, measured by real-time polymerase chain reaction, was increased in aldosterone-infused rats by 2.3, 4.3, and 3.0-fold, respectively. Thiobarbituric acid-reactive substances (TBARS) content in renal cortex was also higher in aldosterone (0.23+/-0.02) than vehicle-infused rats (0.09+/-0.01 nmol/mg protein). ERK1/2, JNK, and BMK1 activities were significantly elevated in aldosterone-infused rats by 3.3, 2.3, and 3.0-fold, respectively, whereas p38MAPK activity was not changed. Concurrent administration of eplerenone or tempol to aldosterone-infused rats prevented the development of hypertension (127+/-2 and 125+/-5 mm Hg), and the elevations of urinary excretion of protein (10+/-2 and 9+/-2 mg/day) or TBARS contents (0.08+/-0.01 and 0.11+/-0.01 nmol/mg protein). Furthermore, eplerenone and tempol treatments normalized the activities of ERK1/2, JNK, and BMK1. These data suggest that ROS and MAPK play a role in the progression of renal injury induced by chronic elevations in aldosterone.  相似文献   
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