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991.
BackgroundInotropic reserve identified by dobutamine or dipyridamole stress echocardiography is associated with a better outcome in patients with idiopathic dilated cardiomyopathy (DCM), although the relative prognostic value of each remains unsettled. The purpose of the present study was to assess the relative prognostic value of dobutamine versus dipyridamole stress echocardiography for the prediction of all-cause death in patients with idiopathic DCM.Methods and ResultsEighty-seven patients (63 were male, aged 54 ± 12 years) with DCM and an ejection fraction less than 35% underwent both dipyridamole and dobutamine stress echocardiography on different days and in a random order. In all patients, wall motion score index and ejection fraction were evaluated at baseline and peak stress. All patients were followed up for an average of 52 months. All-cause death was identified as the prognostic end point. During the follow-up, 26 all-cause deaths occurred (29.8%). On multivariate analysis, either dobutamine echocardiography (relative risk 0.299; P = .02; 95% confidence interval 0.084–0.835) or dipyridamole echocardiography (relative risk 0.161; P < .00; 95% confidence interval 0.07–0.394) added significantly to a prognostic model based on clinical and resting echocardiographic variables. Survival was 83% in patients with dobutamine and 84% in patients with dipyridamole-induced contractile reserve.ConclusionsDobutamine and dipyridamole stress echocardiography have similar feasibility and prognostic accuracy in DCM risk stratification. 相似文献
992.
Simona Bo Roberto Gambino Marilena Durazzo Sabrina Guidi Elisa Tiozzo Federica Ghione Luigi Gentile Maurizio Cassader Gian Franco Pagano 《World journal of gastroenterology : WJG》2005,11(45)
AIM: To examine the relationships between γ -glutamyltransferase (GGT), alanine-aminotransferase (ALT),aspartate-aminotransferase (AST) and various metabolic parameters, C-reactive protein (CRP) and an oxidative stress marker (nitrotyrosine, NT) in subjects without any metabolic abnormalities from a population-based sample.METHODS: Two hundred and five subjects with normal body mass index (BMI), glucose tolerance, and without any metabolic abnormality were studied out of 1339subjects, without known liver diseases, alcohol abuse or use of hepatotoxic drugs, who are representative of the 45-64 aged population of Asti (north-western Italy).RESULTS: In all patients metabolic parameters and hs-CRP levels linearly increase from the lowest to the highest ALT and GGT tertiles, while in subjects without metabolic abnormalities, there is a significant association between fasting glucose, uric acid, waist circumference,hs-CRP, triglyceride values, and GGT levels. In these subjects, male sex, higher hs-CRP and glucose levels are associated with GGT levels in a multiple regression model, after adjustments for multiple confounders.In the same model, median NT levels are significantly associated with the increasing GGT tertile (β = 1.06;95%CI 0.67-1.45), but not with the AST and ALT tertiles.In a multiple regression model, after adjusting for age,sex, BMI, waist, smoking, and alcohol consumption, both NT (β = 0.05; 95%CI 0.02-0.08) and hs-CRP levels (β =0.09; 95%CI 0.03-0.15) are significantly associated with fasting glycemia.CONCLUSION: GGT, an easy, universally standardized and available measurement, could represent an early marker of sub-clinical inflammation and oxidative stress in otherwise healthy individuals. Prospective studies are needed to establish if GGT could predict future diabetes in these subjects. 相似文献
993.
Noninvasive evaluation of flow reserve in the left anterior descending coronary artery in patients with cardiac syndrome X 总被引:1,自引:0,他引:1
Galiuto L Sestito A Barchetta S Sgueglia GA Infusino F La Rosa C Lanza G Crea F 《The American journal of cardiology》2007,99(10):1378-1383
Data on coronary flow reserve (CFR) in patients with syndrome X are still controversial. Further, noninvasive evaluation of epicardial and microvascular flow reserves in these patients has never been performed. In 17 patients with syndrome X and in 17 age- and gender-matched control subjects, CFR in the mid left anterior descending coronary artery (LAD) was evaluated by transthoracic color and pulse-wave Doppler using a 7-mHz probe (Sequoia, Siemens). Peak diastolic LAD flow was calculated at rest and at peak adenosine (140 microg/kg/min intravenously in 90 seconds). Myocardial contrast echocardiography (MCE) was performed at rest and during adenosine use by real-time cadence pulse sequencing and intravenous SonoVue (Bracco; 5 ml at 1 ml/min) and microvascular blood volume (A), velocity (beta), and flow (Axbeta) by replenishing curves (y = A[1 - e(betat)]). CFR was measured by Doppler echocardiography as an adenosine/rest velocity ratio and by MCE as a microvascular volume, velocity, and flow adenosine/rest ratio. Compared with controls, patients with syndrome X demonstrated lower LAD CFR and velocity and flow microvascular flow reserves (p <0.01, <0.005, and <0.005, respectively). In patients with syndrome X, those with angina and ST-segment depression during adenosine testing had even lower LAD CFR and velocity and flow microvascular flow reserves compared with those with no symptoms (p <0.0001, <0.0001, and <0.005, respectively). LAD CFR demonstrated a significant linear correlation with velocity microvascular flow reserve (r = 0.92, p <0.0001) and flow microvascular flow reserve (r = 0.77, p <0.0001). In conclusion, CFR in the LAD, successfully evaluated by transthoracic Doppler echocardiography and MCE, is significantly decreased in patients with syndrome X and even more in those with angina pectoris and ST-segment depression during adenosine testing. Thus, noninvasive evaluation of CFR by echocardiography is feasible and provides information on the severity of microvascular impairment. 相似文献
994.
Conio M Blanchi S Filiberti R Repici A Barbieri M Bilardi C Siersema PD 《Gastrointestinal endoscopy》2007,65(4):714-720
BACKGROUND: The management of patients with refractory hypopharyngeal strictures after surgery in combination with radiation therapy is disappointing, and nutrition through feeding tubes is often required. OBJECTIVE: To evaluate the efficacy and safety of a modified self-expanding Niti-S metal stent in the treatment of hypopharyngeal strictures after combined therapy for laryngeal cancer. DESIGN: Case series. SETTING: A general hospital and a university hospital. PATIENTS: Seven consecutive patients were included. One of them did not have laryngectomy. INTERVENTIONS: All patients received a modified Niti-S stent. MAIN OUTCOME MEASUREMENTS: Improvement of dysphagia, avoiding periodic bougienage, and enteral nutrition through feeding tubes. RESULTS: After placement of the first stent, dysphagia improved in all patients. Six of 7 patients developed stent migration and/or granulomatous tissue ingrowth or overgrowth. Additional stents were placed in all patients after a median of 3 months after the previous stent placement. One patient developed an esophagorespiratory fistula caused by a Polyflex stent. Two patients died of causes unrelated to the stent. The remaining 5 patients remained alive and asymptomatic after a median follow-up of 10 months. LIMITATIONS: Periodic stent exchange. Stent placement did not resolve the stricture definitively. We had a limited number of patients and have no long-term outcome data yet. CONCLUSIONS: The use of this modified Niti-S stent avoids both enteral nutrition through feeding tubes and the need for periodic bougienage in patients with difficult-to-treat benign hypopharyngeal strictures. 相似文献
995.
Seth C. Kalichman David Rompa Kari DiFonzo Dolores Simpson Florence Kyomugisha James Austin Webster Luke 《AIDS and behavior》2001,5(3):291-296
Two studies were conducted to develop scales for assessing self-efficacy to disclose HIV status to sex partners and negotiate safer sex practices among people living with HIV/AIDS. Elicitation research was used to derive 4 sets of scenarios with graduated situational demands that serve as stimulus materials in assessing self-efficacy. Two studies demonstrated that the self-efficacy scales for effective disclosure and negotiating safer sex practices were internally consistent, time stable over 1 month, and demonstrated evidence for validity. Self-efficacy scales also demonstrated evidence of criterion-related, convergent, and divergent validity. Reliable and valid instruments for assessing self-efficacy to make effective HIV status disclosure decisions and practice safer sex were therefore developed and these scales can be used in research to explain, predict, and enhance self-efficacy for these important behaviors. 相似文献
996.
Douglas A. Luke Bobbi J. Carothers Amar Dhand Ryan A. Bell Sarah Moreland‐Russell Cathy C. Sarli Bradley A. Evanoff 《CTS Clinical and Translational Science》2015,8(2):143-149
The importance of transdisciplinary collaboration is growing, though not much is known about how to measure collaboration patterns. The purpose of this paper is to present multiple ways of mapping and evaluating the growth of cross‐disciplinary partnerships over time. Social network analysis was used to examine the impact of a Clinical and Translational Science Award (CTSA) on collaboration patterns. Grant submissions from 2007 through 2010 and publications from 2007 through 2011 of Institute of Clinical and Translational Sciences (ICTS) members were examined. A Cohort Model examining the first‐year ICTS members demonstrated an overall increase in collaborations on grants and publications, as well as an increase in cross‐discipline collaboration as compared to within‐discipline. A Growth Model that included additional members over time demonstrated the same pattern for grant submissions, but a decrease in cross‐discipline collaboration as compared to within‐discipline collaboration for publications. ICTS members generally became more cross‐disciplinary in their collaborations during the CTSA. The exception of publications for the Growth Model may be due to the time lag between funding and publication, as well as pressure for younger scientists to publish in their own fields. Network analysis serves as a valuable tool for evaluating changes in scientific collaboration. 相似文献
997.
TRPV1 unlike TRPV2 is restricted to a subset of mechanically insensitive cutaneous nociceptors responding to heat 总被引:1,自引:0,他引:1
Jeffrey J Lawson Sabrina L McIlwrath C Jeffery Woodbury Brian M Davis H Richard Koerber 《The journal of pain》2008,9(4):298-308
In the present study, a murine ex vivo somatosensory system preparation was used to determine the response characteristics of cutaneous sensory neurons staining positively for TRPV1 or TRPV2. TRPV1 immunostaining was found exclusively (11/11) in a specific set of mechanically insensitive unmyelinated (C) nociceptors that responded to heating of their receptive fields. No cutaneous C-fibers that responded to both mechanical and heat stimuli stained positively for TRPV1 (0/62). The relationship between TRPV2 and heat transduction characteristics was not as clear, as few unmyelinated or myelinated fibers that responded to heat contained TRPV2. TRPV2 was found most frequently in mechanically sensitive myelinated fibers, including both low threshold and high threshold mechanoreceptors (nociceptors). Although TRPV2 was found in only 1 of 6 myelinated polymodal nociceptors, it was found in a majority (10/16) of myelinated mechanical nociceptors. Thus, whereas the in vivo role of TRPV1 as a heat-sensitive channel in cutaneous sensory neurons is clearly defined, the role of TRPV2 in cutaneous neurons remains unknown. These results also suggest that TRPV1 may be essential for heat transduction in a specific subset of mechanically insensitive cutaneous nociceptors and that this subset may constitute a discrete heat input pathway for inflammation-induced thermal pain. PERSPECTIVE: The distinct subset of murine cutaneous nociceptors containing TRPV1 has many attributes in common with mechanically insensitive C-fibers in humans that are believed to play a role in pathological pain states. Therefore, these murine fibers provide a clinically relevant animal model for further study of this group of cutaneous nociceptors. 相似文献
998.
999.
Christine M Gresik Luke P Brewster Gerard Abood Kathy G Supple Geoffrey M Silver Richard L Gamelli Brian J Nickoloff 《Journal of burn care & research》2008,29(3):555-558
Toxic epidermal necrolysis syndrome (TENS) is a severe but rare skin reaction leading to epidermal desquamation of greater than 30% of the TBSA. It is most commonly precipitated by the administration of medication. Frequent complications of this syndrome include local wound infections, respiratory, mucocutaneous, and ocular complications. Ecthyma gangrenosum (EG) is a rare disease characterized by a milliary seeding of the cutaneous tissue with Gram-negative bacteria; it is most commonly seen in immunocompromised individuals. Here we report a 3-year-old boy who developed EG subsequent to TENS. Although he had a complicated and prolonged hospital course, he survived these series of events. To our knowledge, this is the first reported case of TENS/EG in the pediatric population, and the first report of survivability following these illnesses. 相似文献
1000.
Anti-Hu antibodies, also known as ANNA-1, are well characterized in paraneoplastic neuropathies. We present here the first known case of anti-Hu seropositivity, cerebellar ataxia, and sensory neuropathy in association with cervical cancer. 相似文献