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31.
BACKGROUND: Cardiac resynchronization therapy (CRT) for congestive heart failure patients with delayed left ventricular (LV) conduction is clinically beneficial in approximately 70% of patients. Unresolved issues include patient selection, lead placement, and efficacy of LV pacing alone. Being an electrical approach, detailed electrical information during CRT is critical to resolving these issues. However, electrical data from patients have been limited because of the requirement for invasive mapping. OBJECTIVES: The purpose of this study was to provide observations and insights on the variable electrophysiologic responses of the heart to CRT using electrocardiographic imaging (ECGI). METHODS: ECGI is a novel modality for noninvasive epicardial mapping. ECGI was conducted in eight patients undergoing CRT during native rhythm and various pacing modes. RESULTS: In native rhythm (six patients), ventricular activation was heterogeneous, with latest activation in the lateral LV base in three patients and in the anterolateral, midlateral, or inferior LV in the remainder of patients. Anterior LV was susceptible to block and slow conduction. Right ventricular pacing improved electrical synchrony in two of six patients. LV pacing in three of four patients involved fusion with intrinsic excitation resulting in electrical resynchronization similar to biventricular pacing. Although generally electrical synchrony improved significantly with biventricular pacing, it was not always accompanied by clinical benefit. CONCLUSION: Results suggest that (1) when accompanied by fusion, LV pacing alone can be as effective as biventricular pacing for electrical resynchronization; (2) right ventricular pacing is not effective for resynchronization; and (3) efficacy of CRT depends strongly on the patient-specific electrophysiologic substrate.  相似文献   
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Interstitial pneumonitis developed in a patient one week after therapy with nalidixic acid was initiated. The causal association between the drug and the lung disease is based on the temporal relationship, an increased eosinophil count in both peripheral blood and fluid obtained by bronchoalveolar lavage, a positive migration inhibitory factor test with nalidixic acid, and exclusion of other causes. This is, to the best of our knowledge, the first report of a pulmonary hypersensitivity reaction to nalidixic acid.  相似文献   
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BACKGROUND: Experimental studies on healing of colonic anastomosis have been thoroughly investigated. However, clinical parameters of the healing process of anastomosis in the inflamed colon has not yet been reported. METHODS: In the present study, healing of anastomosis in trinitrobenzene-sulfonic acid-induced colitis in rats was assessed by measuring the bursting pressure and bursting wall tension. RESULTS: On postoperative day 4, bursting pressure and bursting wall tension were significantly lower (P<0.001) in rats with colitis with or without anastomosis and normal colon with anastomosis, compared with normal colon without anastomosis. On postoperative day 7, bursting pressure and bursting wall tension of normal colon with anastomosis approached that of normal colon without anastomosis. However, bursting pressure and bursting wall tension of rats with colitis with or without anastomosis remained significantly lower (P<0.001) than the latter. Furthermore, unlike rats without colitis in which perforation occurred mostly at the anastomotic line, the bursting site in colitic rats was predominantly away from the anastomotic line. CONCLUSIONS: These results suggest that in surgery for inflammatory bowel disease, it is the adjoining inflamed bowel wall that is vulnerable to be perforated in response to increasing intraluminal pressure rather than the anastomosis that is braced by the sutures.  相似文献   
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AIM: To prospectively study the incidence and the natural history of acute diverticulitis in young patients.METHODS: A total of 207 patients hospitalized at our hospital between January 2000 to February 2005 with the diagnosis of acute diverticulitis were included. Their demographic characteristics, medical history, physical,radiographic and endoscopic findings as well as therapy were recorded. Patients were followed every 6 mo for the first year and later annually.RESULTS: The mean patients' age was 61 (range 27-92) years. Twenty- five patients (12%) were younger than 45 years. Acute diverticulitis was significantly more prevalent among male in the young age group as compared to the older age group (19/25, 76% vs 61/182,33%, respectively, P = 0.0001). Complications occurred more often in the young age group; 32% vs 13%, (P =0.002). During follow-up, 6 patients (28%) remained asymptomatic in the young age group as compared to 87 patients (55%) in the older age group (P = 0.024). As a result, sigmoidectomies were performed twice as often in the young age group (38% vs 13%, P = 0.002).CONCLUSION: Diverticulitis in young patients has a male predominance, a more aggressive course with a higher rate of complications and a higher recurrence rate. An earlier surgical approach might be considered in young patients with acute diverticulitis.  相似文献   
36.
Hypertension is accompanied by systemic oxidative stress, inflammation, and priming of peripheral polymorphonuclear leukocytes (PMNLs), yet the involvement of these factors in the pathophysiology of hypertension is incompletely understood. We investigated the relationship between oxidative stress, primed PMNLs, and inflammation and the development of hypertension in the Sabra rat model of salt-sensitive hypertension. Sabra hypertension-resistant rats (SBN/y) (salt-resistant) and Sabra hypertension-prone rats (SBH/y) (salt-sensitive) were studied under normal conditions or during salt loading. Systolic blood pressure (BP) was measured by the tail-cuff method. The extent of oxidative stress was evaluated by the rate of superoxide release from PMNLs, plasma-reduced glutathione (GSH) levels, malondialdehyde (MDA) levels (estimated by thiobarbituric acid-reacting substances), and plasma-carbonylated fibrinogen (Western blotting). Plasma fibrinogen levels and the peripheral PMNL count served as indices of inflammation. In SBH/y and SBN/y provided regular chow without salt loading, BP did not rise above baseline values, yet superoxide release, plasma MDA, carbonylated fibrinogen, and PMNL count were higher in SBH/y than in SBN/y, whereas GSH levels were lower in SBH/y. Four weeks of salt loading resulted in a gradual increase in systolic BP in SBH/y to 205+/-3 mm Hg, whereas BP remained in SBN/y at baseline normotensive levels. All the parameters reflecting oxidative stress and inflammation were further aggravated with the development of hypertension in salt-loaded SBH/y. We conclude that primed PMNLs, oxidative stress, and inflammation antecede the development of hypertension in this experimental model of hypertension.  相似文献   
37.
PURPOSE The probability of colorectal cancer is moderately increased among carriers of the APC I1307K polymorphism. However, it is not known if endoscopic surveillance of this high-risk group is warranted. The prevalence of polyps and adenomas in specimens of colorectal cancer who are carriers and noncarriers of the APC I1307K polymorphism is compared. METHOD Prevalence of adenomatous polyps in the pathology specimens of the study participants, stratified by their APC I1307K polymorphism status, was studied in 900 consecutive cases of colorectal cancer diagnosed in northern Israel between 1998 and 2002, within the framework of a population-based, case-controlled study (MECC Study). RESULTS The APC I1307K mutation was detected in 78 colorectal cancer cases (8.7 percent) of the study population. Prevalence was higher among Ashkenazi Jews (11.2 percent) than among non-Ashkenazi Jews (2.7 percent) or Arabs (3.1 percent). After adjustment for age, APC I1307K carriers were significantly more likely than noncarriers to have polyps in their surgical specimen (51.3 percent vs. 32.6 percent, P = 0.002). Adenomas with a tubular component (either tubular adenomas or tubulovillous adenomas), but not villous adenomas, were significantly more frequent among carriers (37.2 percent vs. 23.6 percent, P = 0.005). CONCLUSION Together with former evidence of I1307K being a risk factor for colorectal cancer, these data suggest that colonoscopic surveillance for colorectal adenomas and cancer may be warranted in I1307K carriers, even in the absence of other identifiable risk factors. Supported by the National Institutes of Health grant RO1-CA81488 to S.B.G. and G.R.  相似文献   
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Objective: It is common to study and understand how various illness and disorders result in negative consequences. However, positive experiences have been reported in a range of disabling conditions including multiple sclerosis, heart disease, physical and sensory disabilities. This paper presents a literature review of studies that have explored positive experiences associated with acquired hearing loss, Ménière's disease, and tinnitus. Design: A review of the peer reviewed scientific literature. Study sample: A comprehensive search strategy identified 15 articles after applying inclusion criteria. Results: A range of positive experiences have been reported by patients with hearing and balance disorders and by their significant others. Associations between demographic variables (e.g. age, gender), audiological variables (e.g. severity of the condition, duration) and the reported positive experiences are low. In Ménière's disease, self-reported positive experiences can predict the impact of the condition. However, this phenomenon has not yet been demonstrated in relation to hearing loss and tinnitus. Conclusions: Positive experiences associated with audio-vestibular disorders have been demonstrated. Further research is needed on the long-term benefits of the encouragement of such experiences and positive attitudes in persons with hearing loss, tinnitus, and imbalance.  相似文献   
40.
Objective: To explore the impact, reactions and coping methods of the significant others (SOs) of people with Ménière's disease (MD). Design: SOs of people with MD were asked to answer open-ended questions reporting the ‘life effects’ and ‘positive experiences’ they have had as a result of the partner's condition. The replies to the ‘life effects’ question was categorized using the WHO-ICF framework. The responses of ‘life effects’ from this study and the ‘positive experiences’ reported in a recent study (Manchaiah et al, 2013 Manchaiah V.K.C., Pyykkö, I., Kentala E., Levo H. &; Stephens D. 2013. Positive impact of Ménière's disorder on significant others as well as on patients: Our experience from eighty-eight respondents. Clin Otol, 38, 550554.[Crossref], [PubMed], [Web of Science ®] [Google Scholar]) were evaluated with K-means clustering analysis. Study sample: Eighty-eight SOs (42 male, 42 female, and four did not state gender). Results: While the SOs mainly listed their own problems, a significant number of responses related to the problems of their partner. Personal perspectives tended to focus on the consequences of their partner's condition, whereas in perspectives of their partner they focussed on his/her symptoms. Further, replies from 81 SOs were used in evaluation of responses and were classified into four categories: constrained life attitude; disease burden attitude; care and support attitude; and social isolation attitude. Conclusions: The results of this study support the importance of including the SO of people with MD in the rehabilitation process.  相似文献   
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