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71.
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Neuropsychological clinical decision-making is complicated by the fact that variability in test performance increases with advancing age. This research explores the presence of homogeneous subgroups in 120 neurologically healthy individuals, from 55 to 85 years of age. Subjects at risk for dementing diseases were diagnosed as Aging-Associated Cognitive Decline (AACD) and Mild Cognitive Impairment (MCI). Cluster analysis was applied on 11 neuropsychological variables assessing logical memory immediate recall and retention percentage, visual memory immediate recall and retention, conceptual thinking, naming, verbal fluency, constructional functions, motor speed, flexibility and finger tapping. Five clusters were extracted, one representing cognitively successfully aged, and two consisting of individuals with normal or average level of performance. One cluster was characterized by older subjects with difficulties in visual memory, visuoconstructional functions, and speed and attention, most of the younger subjects in the same cluster had a diagnosis of AACD or MCI. The fifth cluster represented individuals at risk for dementing diseases; most of them were diagnosed having AACD and more than half had a diagnosis of MCI. Age, activity and intellectual levels, and to a lesser degree education, were significantly related to the cluster solution. The present findings caution against treating samples of elderly individuals as homogeneous.  相似文献   
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AIMS: Heart failure is a major cause of hospitalisation, particularly in patients more than 65 years of age in the western world. A common endpoint in studies designed to evaluate treatment effects in heart failure is mortality and morbidity, often reported as an event of hospitalisation. It has recently been reported that this endpoint is misleading with respect to the burden of the disease with regard to the patient, the health service and costs. Furthermore, it can be hypothesized that different treatment effects are better evaluated using more sensitive parameters than those traditionally used in clinical studies. Short-term beneficial effects of exercise training in heart failure patients have previously been showed. Therefore, the aim of this study was to evaluate the long-term effects of exercise training in heart failure patients with regard to different outcome parameters. METHOD AND STUDY GROUP: Patients with chronic heart failure, stabilised on pharmacological treatment, who had participated in a physical training program for 8 weeks, were analysed retrospectively after 5 years. The study group was compared to a matched control group which received conventional treatment and was diagnosed during the same period but not participating in a training program. RESULTS: Exercise training in heart failure patients resulted in significantly less hospitalisation events (2+/-3 vs. 3+/-3, p<0.05) and hospitalisation days (10+/-17 vs. 20+/-27, p<0.05) due to cardiac problems at 5 years after follow-up. Exercise training did not effect mortality. CONCLUSION: Long-term effects of exercise training on burden of disease in chronic heart failure patients is associated with significantly less events and days of hospitalisation due to worsening of cardiac disease.  相似文献   
75.
The present study investigated the utility of rapid microbiological methods in the aetiological diagnosis of community acquired pneumonia (CAP) according to the severity of CAP. Between 1999 and 2004, 384 adult patients with CAP were studied prospectively. In addition to standard microbiological methods, PCR and antigen detection techniques were used to identify pathogens. A total of 230 microbial agents in 209 patients were identified, with 134 (58.2%) identified by antigen detection or PCR tests. Of these 134 microbial agents, 95 (70.9%) were identified only by these rapid methods. Streptococcus pneumoniae urinary antigen detection was positive in 24.3% (81/333) of the patients with a diagnostic yield of 38.7% in those with severe pneumonia. Respiratory viral antigen detection was positive in 11.1% (35/314) of the patients with the highest diagnostic yield (20.3%) in patients with severe pneumonia. Mycoplasma pneumoniae PCR was positive in 7.5% (13/174) of the patients, all of whom were low-risk patients. Only 1 case of Chlamydia pneumoniae was identified by PCR. In conclusion, besides yielding the aetiological diagnosis rapidly, new methods add to the total diagnostic yield in CAP. The diagnostic yield of rapid methods differs according to the severity of the pneumonia.  相似文献   
76.
Fe-doped TiSe2 thin-films were synthesized via low pressure chemical vapor deposition (LPCVD) of a single source precursor: [Fe(η5-C5H4Se)2Ti(η5-C5H5)2]2 (1). Samples were heated at 1000 °C for 1–18 h and cooled to room temperature following two different protocols, which promoted the formation of different phases. The resulting films were analyzed by grazing incidence X-ray diffraction (GIXRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM) and UV/vis spectroscopy. An investigation of the Fe doping limit from a parallel pyrolysis study of FexTiSe2 powders produced in situ during LPCVD depositions has shown an increase in the Fe–TiSe2–Fe layer width with Fe at% increase. Powders were analyzed using powder X-ray diffraction (PXRD) involving Rietveld refinement and XPS. UV/vis measurements of the semiconducting thin films show a shift in band gap with iron doping from 0.1 eV (TiSe2) to 1.46 eV (Fe0.46TiSe2).

Fe-doped TiSe2 thin-films were synthesized via low pressure chemical vapor deposition (LPCVD) of a single source precursor: [Fe(η5-C5H4Se)2Ti(η5-C5H5)2]2 (1).  相似文献   
77.
OBJECTIVES: To examine which individual and environmental factors correlate with unmet physical activity need in old age and predict development of unmet physical activity need (the feeling that one's level of physical activity is inadequate and thus distinct from the recommended amount of physical activity) over a 2‐year follow‐up. DESIGN: Observational prospective cohort study and cross‐sectional analyses. SETTING: Community and research center. PARTICIPANTS: A total of 643 community‐living ambulatory people aged 75 to 81 took part in face‐to‐face interviews and examinations at baseline and 314 at the 2‐year follow‐up. MEASUREMENTS: Unmet physical activity need and its potential individual and environmental correlates were assessed at baseline. Development of unmet physical activity need was assessed over the 2‐year follow‐up period. RESULTS: At baseline, all participants were able to walk at least 500 m outdoors, but 14% perceived unmet physical activity need. Unmet physical activity need was more prevalent in those with musculoskeletal diseases, depressive symptoms, and mobility limitations. Hills in the nearby environment, lack of resting places, and dangerous crossroads correlated with unmet physical activity need at baseline; the association was especially strong in those with walking difficulties. Significant baseline predictors for incident unmet physical activity need (15%) included fear of moving outdoors, hills in the nearby environment, and noisy traffic. CONCLUSION: Unmet physical activity need is common in ambulatory community‐living older people who have health and mobility problems and report negative environmental features in their neighborhood. Solutions to overcome barriers to physical activity need to be developed to promote equal opportunities for physical activity participation.  相似文献   
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79.
Objective. Thymidylate synthase (TS) is the rate-limiting enzyme in the synthesis of pyrimidine nucleotides and as such a critical target for fluoropyrimidines, which are widely used in the treatment of colorectal cancer (CRC). The purpose of this study was to investigate TS expression in the primary tumours (PTs) and their metastases (M) in advanced CRC. Material and methods. TS expression was determined immunohistochemically in paraffin-embedded biopsies of PT-M pairs in 39 CRC patients, as related to the clinical data. Results. There was no difference in the mean TS index of PTs compared with that of M, 1.25 and 1.14, respectively (p=0.12). TS expression of PTs was above the mean more often than that of M (61.5% and 41.0%, respectively, p=0.035). High TS expression in PTs was significantly related to high expression in M (the Fisher exact test, p=0.001). Using the absolute index values, TS expression in PT and M was significantly correlated (Pearson R=0.501, p=0.001). In 29/39 (74.3%) pairs, PT and M had concordant expression levels (Cohen's kappa 0.508, 95% CI 0.260–0.756, p=0.001; intraclass correlation coefficient (ICC) = 0.679, 95% CI 0.358–0.836, p=0.0001). No significant association was found between TS expression and any of the clinicopathological variables, disease outcome (DFS, DSS) or its response to treatment in univariate or multivariate analysis. Conclusions. Albeit usually higher, TS expression in PT was closely correlated with TS expression in M. This suggests that measurement of TS in primary CRC accurately predicts TS expression in subsequent metastases, which may help in selecting those patients most likely to respond to 5-FU-based regimens.  相似文献   
80.
Chlamydia pneumoniae has been associated with cardiovascular diseases and has been shown by different methods to be present in atherosclerotic lesions. However, not all studies have found C. pneumoniae in atherosclerotic tissues. We compared polymerase chain reaction (PCR) methods, in situ hybridization (ISH), and measurement of chlamydial lipopolysaccharide (cLPS) by enzyme immunoassay (EIA) from homogenized atherosclerotic tissue in the detection of C. pneumoniae. In a study population of 110 patients with carotid artery disease, cLPS was found in 22.2%, and DNA by PCR was found in 34.3% and by ISH in 39.4% of the samples. Poor repeatability was shown to complicate PCR, and the technical problems inherent in ISH were not insignificant. In contrast, the cLPS EIA test was fast and easy to perform. If the sensitivity could be increased, for example, by testing multiple tissue pieces, cLPS EIA might provide a standardized commercial method for the detection of chlamydia in tissue samples, and it, thus, merits further characterization and validation in different patient populations.  相似文献   
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