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81.

Introduction

The aim of the study was to assess myocardial ischemia by analysis of ST-segment changes in high-resolution body surface potential maps (HR-BSPM) measured at rest and during an exercise stress test.

Material and methods

The study was carried out on a group of 28 patients with stable coronary artery disease and 15 healthy volunteers. The HR-BSPM were measured at rest and during the exercise stress test on a supine ergometer. The workload was increased in stages by 25 W every 2 min, beginning at 50 W. The maps of ST-segment depression (ST60) were calculated from time averaged recordings at rest and at maximal workload.

Results

The efficiency in detection of myocardial ischemia was higher for HR-BSPM than for standard 12-lead electrocardiography (ECG) when both methods were evaluated by outcomes of coronarography. The sensitivity of HR-BSPM was 82.4% while for the standard 12-lead ECG exercise stress test it was 58.8%. For some patients significant changes in the ST segment were observed at stress HR-BSPM but were not visible in standard 12-lead ECG recorded under the same conditions.

Conclusions

Obtained high values of sensitivity and specificity in myocardial ischemia detection suggest that maps of ST60 calculated from HR-BSPM can improve detection of patients with ischemic heart disease in comparison to the standard electrocardiographic exercise stress test examinations.  相似文献   
82.
Introduction: Helicobacter pylori is a bacteria which infects half the world population and is an important cause of gastric cancer. The eradication therapy is not always effective because resistance to antimicrobials may occur. The aim of this study was to determine the susceptibility profile of H. pylori to amoxicillin, clarithromycin and ciprofloxacin in the population of Southern Brazil. Material and methods: Fifty four samples of H. pylori were evaluated. The antibiotics susceptibility was determined according to the guidelines of the British Society for Antimicrobial Chemotherapy and the Comité de l''Antibiogramme de la Société Française de Microbiologie. Results: Six (11.1%) H. pylori isolates were resistant to clarithromycin, one (1.9%) to amoxicillin and three (5.5%) to ciprofloxacin. These indices of resistance are considered satisfactory and show that all of these antibiotics can be used in the empirical therapy. Conclusion: The antibiotics amoxicillin and clarithromycin are still a good option for first line anti-H. pylori treatment in the population of Southern Brazil.  相似文献   
83.
Background: Cannabinoid receptor agonists inhibit inflammatory hyperalgesia in animal models. Nonselective cannabinoid receptor agonists also produce central nervous system (CNS) side effects. Agonists selective for CB2 cannabinoid receptors, which are not found in the CNS, do not produce the CNS effects typical of nonselective cannabinoid receptor agonists but do inhibit acute nociception. The authors used the CB2 receptor-selective agonist AM1241 to test the hypothesis that selective activation of peripheral CB2 receptors inhibits inflammatory hyperalgesia.

Methods: Rats were injected in the hind paw with carrageenan or capsaicin. Paw withdrawal latencies were measured using a focused thermal stimulus. The effects of peripheral CB2 receptor activation were determined by using local injection of AM1241. CB2 receptor mediation of the actions of AM1241 was shown by using the CB2 receptor-selective antagonist AM630 and the CB1 receptor-selective antagonist AM251.

Results: AM1241 fully reversed carrageenan-induced inflammatory thermal hyperalgesia when injected into the inflamed paw. In contrast, AM1241 injected into the contralateral paw had no effect, showing that its effects were local. AM1241 also reversed the local edema produced by hind paw carrageenan injection. The effects of AM1241 were reversed by the CB2 receptor-selective antagonist AM630, but not by the CB1 receptor-selective antagonist AM251. AM1241 also inhibited flinching and thermal hyperalgesia produced by hind paw capsaicin injection.  相似文献   

84.
85.
There are few Western studies evaluating prognostic factors for survival in patients with hepatocellular carcinoma (HCC) and the influence on survival of various therapeutic options including ortbotopic liver transplantation (OLT). A retrospective analysis was performed of 122 patients with HCC treated at the University of Alabama at Birmingham from January 1990 through December 1999. Clinicopathologic and treatment factors were analyzed with overall survival as the main outcome variable. Median age was 62 years. Most patients were male (74%) and white (79%). Eighty patients (66%) had associated cirrhosis. Sixty-three percent of patients presented with American Joint Committee on Cancer (AJCC) stage III or lV tumors. The median follow-up for survivors was 22 months. The l-, 3-, and 5-year actuarial survival rates for the entire cohort were 46%, 24%, and 17%, respectively. On multivariate analysis, ablative surgery (P = 0.003), AJCC stages I and II (P = 0.0012), and absence of vascular invasion (P = 0.0001) were found to be independent favorable characteristics. Forty-four patients underwent surgical resection (including OLT, n = 20) or a surgical ablative procedure. All but two nonsurgical patients died of disease. The actuarial l-, 3-, and S-year survival rates for this group were 80%, 71%, and 61%, respectively. On multivariate analysis of the surgical group, only vascular invasion was associated with poor prognosis (P = 0.001). OLT was associated with a favorable prognosis on univariate analysis (P = 0.02). Forty percent of patients who received transplants underwent local/regional treatment before transplantation and the outcome in these patients was no different from that in other transplant patients. Surgical treatment is the only potential curative option for HCC, and qualifying for liver transplantation may be a favorable prognostic factor in surgical patients. Local/regional therapy prior to transplantation may provide a bridge to OLT without an increase in tumor-related mortality.  相似文献   
86.
This study aims to assess the diversity of campylobacteria (Campylobacter and Arcobacter) in human fecal samples from patients with diarrhea (n = 140) and asymptomatic controls (n = 116) in Chile, using a combination of traditional culture and molecular methods. The culture methods detected campylobacteria in 10.7% of the patients with diarrhea and in 1.7% of the controls. In contrast, the molecular methods detected campylobacteria more often than the traditional culture, with a prevalence of 25.7% and 5.2%, respectively. The traditional methods only recovered the species Campylobacter jejuni, Campylobacter coli, and Arcobacter butzleri, whereas the molecular methods additionally detected the emergent species Campylobacter concisus and Campylobacter ureolyticus.  相似文献   
87.
Graphene with defects is a vital support material since it improves the catalytic activity and stability of nanoparticles. Here, a density functional theory study was conducted to investigate the stability, energy, and reactivity properties of NinPdn (n = 1–3) clusters supported on graphene with different defects (i.e., graphene with monovacancy and pyridinic N-doped graphene with one, two, and three N atoms). On the interaction between the clusters and graphene with defects, the charge was transferred from the clusters to the modified graphene, and it was observed that the binding energy between them was substantially higher than that previously reported for Pd-based clusters supported on pristine graphene. The vertical ionization potential calculated for the clusters supported on modified graphene decreased compared with that calculated for free clusters. In contrast, vertical electron affinity values for the clusters supported on graphene with defects increased compared with those calculated for free clusters. In addition, the chemical hardness calculated for the clusters supported on modified graphene was decreased compared with free clusters, suggesting that the former may exhibit higher reactivity than the latter. Therefore, it could be inferred that graphene with defects is a good support material because it enhances the stability and reactivity of the Pd-based alloy clusters supported on PNG.  相似文献   
88.
To describe a possible case of unilateral keratoconus in a patient with continual eye rubbing due to an ipsilateral nasolacrimal obstruction in a 17-year-old woman complaint of progressing low visual acuity in the left eye. Presented with constant epiphora in the left eye throughout her life as a result of ipsilateral nasolacrimal obstruction, which required frequent wiping of this eye. Based on ocular examination, the patient was diagnosed as having unilateral keratoconus in the left eye. As in other studies, keratoconus is thought to be associated with persistent eye rubbing. This patient represents a case of unilateral keratoconus, where there is a confirmed history of habitual eye rubbing due to ipsilateral nasolacrimal obstruction, thereby suggesting a possible causal relationship between eye rubbing and keratoconus.  相似文献   
89.
BACKGROUND: Most studies focusing on the occupational hazards associated with forklift operation have examined risks of fatalities and traumatic injuries. Few studies have examined the magnitude of risk of musculoskeletal disorders (MSDs). We review and critically appraise the epidemiological studies conducted on forklift operators in relation to MSDs, such as lower back pain and neck problems. METHODS: A comprehensive search of databases resulted in the identification of seven epidemiological studies that addressed MSDs. A critical appraisal of these studies was conducted using epidemiological principles and a meta-analysis approach that involved the use of the confidence limit method to determine an overall "meta-odds ratio." RESULTS: The methodological quality of these studies ranged from "marginal" to "average" with the exception of one study, which was considered "good." The meta-odds ratio for lower back pain among forklift operators was 2.13 (95% CI: 1.57, 2.87). CONCLUSIONS: Our results suggest that forklift operators are at increased risk of lower back pain. Additional high quality epidemiological studies are needed in the US, however, to determine the magnitude of risk for MSDs. In this regard, studies should address not only lower back pain among forklifts operators, but also neck pain. A full exposure assessment of physical and non-physical factors in these studies is needed.  相似文献   
90.
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