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BACKGROUND: To ascertain survival of ischemic advanced heart failure patients by treatment allocation, we examined the outcome of transplant assessment patients allocated to medical therapy, high-risk conventional surgery, or transplantation. METHODS: Patients were identified from the Papworth transplant database and excluded if primary etiology was not ischemic. Grouping was undertaken according to treatment allocation at initial assessment, and analysis was performed by intention to treat. Survival was computed from the time of assessment and Cox regression used to stratify patients according risk with the Heart Failure Survival Score. RESULTS: From May 1993 to September 2001, a total of 755 patients were admitted for transplant assessment, with 348 (46.1%) identified as having heart failure of ischemic origin. Variables required for calculation of the Heart Failure Survival Score was available in 273 patients (78.4%), and 20 patients (7.3%) were lost to follow-up. Of the remaining 253 patients, 89 (35.2%) were allocated to medical therapy, 32 (12.6%) to surgery, and 132 (52.2%) to transplantation. The relative risk (95% confidence limit) of death compared with medical therapy was 0.62 (0.28, 1.40) for surgery and 0.38 (0.24, 0.61) for transplantation in medium- to high-risk patients. For low-risk patients, the relative risks for death compared with medical therapy were 1.87 (0.63, 5.60) for surgery and 1.97 (0.79, 4.96) for transplantation. CONCLUSIONS: Transplantation improved survival of medium- and high-risk patients compared with medical therapy. In the low-risk group, this was not evident. However, repeated assessment of risk is required because the hazard for death rises steadily after the third year in these patients.  相似文献   
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We examined the cytotoxic potential of nine N-[2-substituted-2-(2-thienyl)ethyl] piperazinyl quinolone derivatives on human oral epithelial mouth carcinoma (KB) and human squamous carcinoma (A431) cell lines. Phototoxic properties of these compounds were also evaluated by mouse 3T3 fibroblast under ultraviolet-A (UVA) irradiation. The percent of cell viability was evaluated by MTT assay. Compound 6 having a 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] group attached to N4 position of piperazine ring of enoxacin showed the highest cytotoxicity potential on both A431 and KB cell lines (IC50 of 3.11+/-0.52 and 4.91+/-1.94 microg/ml, respectively). While some of the other tested compounds exhibited clear phototoxic potential in 3T3 cell line, compound 6 showed only a minor potential of phototoxicity. These findings suggest the high potential of 4-[2-(phenylmethoxyimino)-2-(2-thienyl)ethyl] derivative of enoxacin as a cytotoxic compound with low potency of phototoxic reactions. The mentioned chemical was identified to be of special interest for further characterization.  相似文献   
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The 5-HT3-receptor antagonist, ondansetron, has been shown to have positive effects in selected in-vivo models of memory impairment and anxiety. The exact mechanisms underlying such bioactivities are unknown. In the present work, an 86Rb efflux bioassay was used to show that ondansetron has a unique ability to block voltage-gated potassium channels in TE671 human neuroblastoma cells. This intrinsic potassium-channel-blocking (KCB) property is relatively weak (IC50 20 (M), but is not shared by other 5-HT3-receptor ligands including zatosetron, MDL 72222, LY 278, 584, zacopride, 1-phenylbiguanide, and ICS 205–930 (tropisetron). Pre-incubation of the target neuroblastoma cells with several 5-HT-receptor ligands including 5-hydroxytryptamine, 8-OH-DPAT, ketanserin, 2-methyl-5-HT, as well as a number of potent 5-HT3 agonists and antagonists and two selective neurotoxins, failed to abolish the KCB action of ondansetron. A preliminary structure-activity relationship analysis indicates that the KCB activity of ondansetron is almost entirely attributable to its structural nucleus, 2,3-dihyro-9-methyl-4(lH)-carbazolone. It is hypothesized that the KCB action of ondansetron is mediated through receptors other than 5-HT3 receptors. The KCB activity of ondansetron may be a significant factor in the in-vivo cognition-enhancing activities of this compound, conceivably due to depolarization of the hippocampal synaptic membranes and a consequent augmentation of neurotransmission.  相似文献   
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Background  

Cardiovascular disease remains the leading killer of women in most developed areas of the world. Rates of physical inactivity and poor nutrition, which are two of the most important modifiable risk factors for cardiovascular disease in women, are substantial. This study sought to examine the effectiveness of a community-based lifestyle-modification program on increasing women's physical activity in a randomized trial guided by community-based participatory research (CBPR) methods.  相似文献   
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This study aimed to determine the effects of anti-CD154 on T cell cytokine profiles and ocular chemokine gene expression after high-risk corneal transplantation and to specifically determine if CD154 blockade is associated with a switch from a Th1 to a Th2 alloimmune response. Mice were used as recipients of syngeneic or multiple minor H or MHC antigen-mismatched corneal grafts. Recipient beds were neovascularized (high-risk). Hosts were randomized to receive either anti-CD154 antibody or control immunoglobulin (Ig) perioperatively. Two weeks after corneal transplantation, allospecific delayed-type hypersensitivity (DTH) was evaluated. Frequencies of interferon-gamma (IFN-gamma)-, interleukin-2 (IL-2)-, IL-4-, and IL-5-secreting T cells in the hosts were measured by enzyme-linked immunospot (ELISPOT) assay. Ocular chemokine gene expression in anti-CD154-treated and control hamster Ig-treated groups was determined using a multiprobe ribonuclease protection assay (RPA). Leukocyte infiltration of corneal grafts was evaluated microscopically. Anti-CD154-treated mice did not exhibit allospecific DTH. The frequencies of Th1 cytokine-producing but not Th2 cytokine-producing T cells were significantly reduced in anti-CD154-treated hosts. Postoperative mRNA levels of RANTES and macrophage inflammatory protein-1beta (MIP-1beta) in anti-CD154-treated eyes were substantially suppressed compared with hamster Ig-treated controls. Leukocyte infiltration was profoundly suppressed in grafts of anti-CD154-treated hosts. These data demonstrate that blockade of the CD40-CD154 costimulatory pathway after corneal transplantation inhibits Th1-mediated responses but does not induce a switch to a Th2-specific response. In addition, anti-CD154 therapy suppresses ocular chemokine gene expression and leukocytic infiltration into allografts.  相似文献   
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INTRODUCTION: Broncholithiasis is often seen after chronic granulomatous diseases such as tuberculosis and hystoplasmosis and leads to a wide spectrum of signs and symptoms; including hemoptysis which often needs surgical management. The goal of this study is evaluation of surgery in patients with tuberculous broncholithiasis who present with hemoptysis. MATERIALS AND METHODS: In this study all patients with tuberculous broncholithiasis had been operated on between 1991 and 2005, followed up at least 6 months and at most 9 years, and studied relating to age, sex, clinical symptoms, diagnostic methods, type of surgical treatment, complications and mortality. RESULTS: Overall 5 patients have been studied (male:female=2:3, mean=31 years); 2 with severe and 3 mild to moderate and recurring hemoptysis, lesion at left in 80% and at right in 1, in 3 patients some degree of bronchiectasia was seen, in 4 the lesion was visible in bronchoscopy and endoscopic removal of the lesion failed in all. Three of patients underwent pulmonary resections and in 2 broncholithotomy has been done. In follow-up, patients treated with pulmonary resection have had no subsequent problems, but in patients treated with broncholithotomy due to occurring late bronchiectasia, re-operation and pulmonary resection was inavoidable. There was no mortality. CONCLUSION: Regarding the dangers of hemoptysis and excellent results of surgery and possible occurance of late bronchiectasia after broncholithotomy, the results of our study show that pulmonary resection distal to the lesion and as the retention of lung of parenchyma is preferable. Broncholithotomy should be done only in patients in whom pulmonary resection is not technically possible. Because of the very low occurance of this complication complete studies are needed.  相似文献   
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Whole-heart cine MRI using real-time respiratory self-gating.   总被引:1,自引:0,他引:1  
Two-dimensional (2D) breath-hold cine MRI is used to assess cardiac anatomy and function. However, this technique requires cooperation from the patient, and in some cases the scan planning is complicated. Isotropic nonangulated three-dimensional (3D) cardiac MR can overcome some of these problems because it requires minimal planning and can be reformatted in any plane. However, current methods, even those that use undersampling techniques, involve breath-holding for periods that are too long for many patients. Free-breathing respiratory gating sequences represent a possible solution for realizing 3D cine imaging. A real-time respiratory self-gating technique for whole-heart cine MRI is presented. The technique enables assessment of cardiac anatomy and function with minimum planning or patient cooperation. Nonangulated isotropic 3D data were acquired from five healthy volunteers and then reformatted into 2D clinical views. The respiratory self-gating technique is shown to improve image quality in free-breathing scanning. In addition, ventricular volumetric data obtained using the 3D approach were comparable to those acquired with the conventional multislice 2D approach.  相似文献   
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