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31.
OBJECTIVE: The present study tested the hypothesis that cortical electroencephalographic (EEG) rhythms. change across normal elderly (Nold), mild cognitive impairment (MCI), and Alzheimer's disease (AD) subjects as a function of the global cognitive level. METHODS: Resting eyes-closed EEG data were recorded in 155 MCI, 193 mild AD, and 126 age-matched Nold subjects. EEG rhythms of interest were delta (2-4 Hz), theta (4-8 Hz), alpha 1 (8-10.5 Hz), alpha 2 (10.5-13 Hz), beta 1 (13-20 Hz), and beta 2 (20-30 Hz). EEG cortical sources were estimated by LORETA. RESULTS: Occipital delta and alpha 1 sources in parietal, occipital, temporal, and 'limbic' areas had an intermediate magnitude in MCI subjects compared to mild AD and Nold subjects. These five EEG sources presented both linear and nonlinear (linear, exponential, logarithmic, and power) correlations with the global cognitive level (as revealed by mini mental state examination score) across all subjects. CONCLUSIONS: Cortical EEG rhythms change in pathological aging as a function of the global cognitive level. SIGNIFICANCE: The present functional data on large populations support the 'transitional hypothesis' of a shadow zone across normality, pre-clinical stage of dementia (MCI), and AD.  相似文献   
32.
Two prominent trends in contemporary child welfare, permanency planning and the family-centered model of care, are old theoretical ideas that have had great difficulty in finding corresponding practice methodologies. This article presents a practical model and discussion of the strategy and tactics involved in the process of developing and implementing a family-centered model by providing an effective parent involvement program in the residential treatment setting. Both didactic and experiential components are suggested, with emphasis on the latter in the context of planned change and the needs of children, parents, staff, and agency administration.  相似文献   
33.
As assessed by both standard histological staining and immunochemistry, intraperitoneal inoculation of C. burnetii in guinea pigs led to pathologic changes mainly in the liver, whereas intranasal inoculation led to pathologic changes mainly in the lungs. Myocarditis and positive blood cultures were observed only in those animals which received the highest inoculum. We therefore conclude that both the route of infection and the size of the inoculum influence clinical expression in acute Q fever.  相似文献   
34.
The effects of sedative-hypnotic doses of propofol on respiratory drive and pattern have not yet been extensively described. Repeated small boluses of propofol (0.6-0.3 mg.kg-1) were administered to ten ASA I patients undergoing carpal tunnel release using regional anaesthesia. Airway pressure, capnography and pneumotachography were continuously recorded. With respect to basal values, no significant variations of respiratory rate, minute volume, tidal volume, inspiratory and expiratory time, total expiratory cycle, Ti/Ttot, TV/Ti, P0.1, EtCO2 and blood gas analysis were observed. Low doses of propofol, to maintain conscious sedation of light sleep, have not been shown to cause respiratory depression.  相似文献   
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36.
In the Abruzzo Region (Central Italy) there is a lack of measurements of gamma-ray activity in soils and waters. For this reason, we have planned to carry out a systematic measurement of soils in the area of the Provincia dell'Aquila, which covers about one-half of the entire region. In this paper we report the results obtained from 56 soil samples, collected in the northern part of the area of interest (about one-fourth of the total area under study). The results, in terms of content of uranium, thorium and potassium and the activity of caesium are reported, as well as the details on the experimental procedure. The results show a limited content of K and U, with no large variations from site to site, in agreement with the expectations based on the knowledge of the geo-lithological nature of the soil. The amount of Th is also quite limited, with a few exceptions where the Th content is up to five times the average value. Caesium, originated from the fall-out following the Chernobyl accident, is very irregularly distributed owing to the complicated orography of the land. Future plans are also shortly discussed.  相似文献   
37.
BACKGROUND. The relation between body mass index and acute myocardial infarction was analyzed using data from a multicentric case-control study conducted in Italy between September 1988 and June 1989 within the framework of the GISSI-2 trial. METHODS. Subjects were 916 patients with acute myocardial infarction and no history of cardiovascular disease and 1,106 controls hospitalized for acute conditions not related to known or suspected risk factors for ischaemic heart disease. RESULTS. Relative to the lowest quintile of the Quetelet Index (weight/height2) the estimated risks for subsequent quintiles were 1.2 (95% confidence intervals, (CI): 0.9 to 1.6), 1.7 (95% CI: 1.2 to 2.2), 1.8 (95% CI: 1.4 to 2.4), and 2.2 (95% CI: 1.7 to 3.0) when adjustment was made for age, sex, education, and smoking habits by means of logistic regression. The association was consistent across strata of sex, education, and smoking status, but not age. The estimated risk for subjects in the fifth quintile of the Quetelet Index relative to those in the first was 4.1 under 55 years of age, but only 1.7 between 55 and 64 years and 1.5 above age 65. CONCLUSION. The relation between body mass and myocardial infarction was explained, at least in part, by higher serum cholesterol levels and the prevalence of diabetes and hypertension among fatter subjects. This does not, however, totally eclipse a possible causal relation between body mass and risk of myocardial infarction, since these conditions are a consequence, rather than a confounder, of overweight.  相似文献   
38.
A discussion of the present role of varicocele in the management of the subfertile couple is presented, with emphasis on detection techniques and the increasing awareness of the presence of bilateral varicocele. The indications and techniques of surgical management are discussed, with particular emphasis on the use of the operating microscope to dissect the spermatic cord at the level of the external inguinal ring under local anesthesia on an outpatient basis with significant cost savings to the patient.  相似文献   
39.
A study was carried out to analyse trends in cancer mortality sex differentials. This study compared age-standardized sex ratio values for mortality from 18 cancers (or groups of cancers), and total cancer mortality over the period 1950-1989 in 24 European countries, for 4 age groups (all ages, 20-44 years, 45-64 years, and 65 years and over). For lung cancer and other tobacco-related neoplasms, appreciable rises in sex ratio values were observed until the late 1970s, particularly in Southern and Eastern Europe, before levelling off in recent years, particularly among the younger age groups. In the late 1980s, the range of variation in overall age-standardized sex ratios for lung cancer was between 2 and 3 in the United Kingdom and in Nordic countries, and around or over 10 in Southern Europe. In young adults, the decline in sex ratio values observed in Denmark and Sweden (unity), and in other Nordic countries and in the United Kingdom (around or below 2) reflects a levelling of lung cancer in young males and an increase in young females. This clearly indicates that young women are a priority target group for smoking control interventions in Europe. Appreciable cohort effects were also observed for stomach cancer: rises in sex ratio values were greater in, or restricted to, middle- and older age groups, whereas in the young there was some tendency towards a levelling in sex differentials. The overall sex ratio values for stomach cancer were around 2 in most areas of Europe in the late 1980s. For intestinal cancer, sex ratio values showed some tendency to rise, reaching a level of 1.3-1.7 in the late 1980s; steady rises were also registered in sex ratio values for melanoma (skin cancer), reaching 1.5-1.8 in the late 1980s in most countries. These upward trends which were minor or inconsistent at younger ages in several countries became progressively stronger with advancing age. Sex ratio values were below unity for cancers of the gallbladder and the thyroid. Sex ratio values tended to rise also for leukaemia (from 1.2-1.5 to 1.5-1.7), but showed no noticeable trend for lymphomas or myeloma. The overall sex ratio values for total cancer mortality in the 1950s were between 1.2 and 1.4 in most European countries. Thereafter, they rose appreciably in several countries, reaching 1.9 in Czechoslovakia, Italy and Poland, and 2.3 in France.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
40.
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