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The pharmacodynamic effect of a homologous series of aminomethyldimethyl-(methoxyphenyl)-silane derivatives have been tested on isolated guinea-pig left atria. All molecules increase the force of contraction to different degrees by a partly direct and partly indirect mechanism (measured on atria isolated from reserpine treated guinea-pigs). The positive inotropic effect is reduced by bupranolol. Furthermore the compounds show an antagonistic effect to orciprenaline. The membrane stabilising action is lowest for those compounds showing the highest inotropic effects and vice versa.  相似文献   
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Objective: We analyzed the histologic and immunohistochemical changes in the endometrial leukocytic subpopulations to determine which of them are characteristic of chronic endometritis.Results: Endometrial biopsies from 25 cases of chronic endometritis and 35 controls were studied. Characteristic morphologic findings included the presence of a plasma cell infiltrate, and a prominent, albeit non-specific, lymphocytic infiltrate in all patients with endometritis. A neutrophilic infiltrate was also noted in 90% of the patients. Other non-specific histologic findings included occasional prominent lymphoid aggregates, stromal edema, hemorrhage, and necrosis and cystic dilation of some glands in endometria of patients with chronic endometritis. Endometrial immune cells were investigated immunohistochemically using antibodies to CD3 (pan-T), CD20 (pan-B, L26), and Ham-56 (macrophage). In control patients, endometrial immune cells were predominantly composed of CD3 and Ham-56 positive cells. CD20 positive cells comprised <2% of immune cells in control patients [mean: <2 cells/high power field (HPF)]. Large numbers of CD20 and CD3 lymphocytes were seen in endometria of patients with chronic endometritis. A semiquantitative analysis showed that the numbers of CD20 and CD3 positive cells in patients with chronic endometritis were increased 50- and 3-fold, respectively, when compared to those of control patients (mean B cells: 49 vs. 2 cells/HPF; mean T cells: 149 vs. 45 cells/HPF). CD20 positive cells were predominantly seen in subepithelial and periglandular aggregates. CD3 positive cells had a predominant stromal distribution and an occasional intra- or subepithelial localization. There was no difference in the number and distribution of Ham-56 positive cells in patients with or without endometritis.Conclusions: These findings suggest that CD20 cells may have a significant role in the pathogenesis of chronic endometritis and that immunostaining for B and T lymphocytes could be used in confirming the diagnosis of endometritis or in diagnosing subclinical or progressing endometritis in which plasma cells could not be detected or are rarely identified.  相似文献   
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Computed tomography (CT) and magnetic resonance imaging (MRI) of the orbit have been competing for the hearts and minds of health care providers for well over 2 decades. While several drawbacks pertaining to CT have been outlined since the introduction of MRI, CT remains the standard diagnostic test for evaluating cross-sectional, 2 or 3-dimensional images of the body.  相似文献   
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Subintimal recanalization is beneficial in selected patients with peripheral chronic total occlusions (CTO). However, in complex cases, re‐entry into the true arterial lumen may prove to be unsuccessful with a conventional guidewire or a re‐entry catheter when using standard femoral artery access. Our case series describes these technical dilemmas along with strategies that can be utilized to overcome these challenges. © 2011 Wiley‐Liss, Inc.  相似文献   
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Digoxin remains one of the oldest therapies for heart failure; however, its safety and efficacy have been controversial since its initial use. Questions that remain include the clinical efficacy of digoxin when added to contemporary medical therapy, when and if it should be added, and how to minimize adverse effects. In this review, we will summarize recent data on the use of digoxin in systolic heart failure and address some of the controversies regarding the role of digoxin in the modern era of heart failure treatment.  相似文献   
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