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101.
Impaired effortful cognition in depression   总被引:3,自引:0,他引:3  
Depressed patients have been reported to have deficits in "effortful," but not effortless, cognitive functions compared to healthy volunteers. To test the hypothesis that the effortful cognitive deficits in major depression are not simply a function of psychiatric illness or hospitalization, we administered both effort-demanding and effortless cognitive tasks to 17 inpatients with major affective disorder and 17 hospitalized psychiatric controls. The depressed patients performed significantly more poorly than the controls on the effort-demanding task. The groups did not differ on the effortless task. These findings suggest that depressed patients are impaired in performing effort-demanding cognitive tasks compared to nondepressed psychiatric patients.  相似文献   
102.
In Norway, the use of cannabis was introduced by a resourceful group of oppositional middle-class adolescents in the late 1960s. At the beginning of the 1970s there were, however, signs of a change in the recruitment of the users: youths in trouble from lower social levels gradually started to use the drug. In a prospective longitudinal study of 1311 Norwegian pupils aged 13-19, the possible links between normative and political opposition, mental health and the use of cannabis were investigated. The findings indicate that the group that experiments with cannabis, and use the drugs a few times, is still mainly characterized by a political and normative "oppositional" engagement. Heavy users of cannabis, however, also have family problems and suffer from poor mental health. Thus, the study draws attention to the importance of distinguishing between two different clusters of longitudinal predictors for adolescent cannabis use: the first consists of subcultural opposition and certain personality traits, and seems to predict the earlier stages of use. The second consists of psychosocial problems and poor mental health. From this study one may not conclude that this second cluster predicts heavy cannabis involvement. We have, however, shown that it correlates with heavy involvement, cross-sectionally.  相似文献   
103.
104.
This article examines a specific management reform at three hospitals in a Danish county. Management reform at the hospital level implies a decentralization of responsibility and power to the departmental level. Along with increased responsibility and power, departments get the message: keep your budgets and keep your output level. This preliminary analysis indicates that departmental budgets can be a way of containing costs in clinical departments. Non-staff expenditures especially are subjected to reductions. The system still seems to 'favour' doctors and nurses, but less than in a system with traditional budgetary institutions. The behaviour of the top-management teams shows that the output constraint is not seriously meant. Departments are allowed to reduce capacity, with declining output, with the knowledge of the top-management team. The declining output makes it easier to departments ceteris paribus to keep within their budgets. And that makes it easier for the top-management team to keep the overall hospital budget. The obligation to keep the overall hospital budget is thus an important criterion of success in the eyes of the political masters of hospitals.  相似文献   
105.
Evidence that the shift of services from secondary to primary care is creating extra work for GPs is limited. A study showed that it is possible to quantify additional workload for GPs, but that certain aspects, such as measuring the time input, remain problematic. Future research needs to agree workload definitions, employ sensitive measures other than consultation rates, and distinguish between workload in practices and that of individual practitioners.  相似文献   
106.
Summary The coding sequences of the core proteins p17 and p28 of caprine arthritis-encephalitis virus (CAEV) were amplified using the polymerase chain reaction and cloned into the plasmid expression vector p-GEX-2T. Both p17 and p28 were expressed as fusion proteins with glutathione S-transferase. The recombinant proteins were affinity purified from induced bacterial lysates using glutathione-agarose beads. The purified proteins were used in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies against CAEV in goat sera and milk samples. Three different ELISA tests were developed based on p17, p28 or the combination of these two recombinant proteins (p17+p28). A comparison was made to an ELISA based on purified whole virus particles and to agar immunodiffusion test (AGID). Sera with conflicting results in the different ELISA tests were examined by Western blotting. There was a high correlation between the ELISA tests based on p17+p28 recombinant proteins and whole virus ELISA, with an estimated value of 0.92. Only 72–75% of the sera that tested positive in these two ELISA tests were positive in AGID. Antibodies to CAEV were detected in significantly more animals when serum samples were tested compared to milk samples. Based on the time and materials required to prepare the reagents, the recombinant based ELISA test was less expensive than the whole virus ELISA.  相似文献   
107.
108.
OBJECTIVE: Abdominal fat has been shown to be associated with several adverse outcomes including diabetes, cardiovascular disease, and hypertension. Risk factors for abdominal fatness include genetic effects, age, and gender. Most recently, it has been hypothesized that psychological factors, as well as behavioral factors, may play a part in where fat is distributed. The purpose of this study was to assess the longitudinal predictive power of psychological variables (cynicism, anger, anxiety, and depression) measured in 1987 on waist-hip ratio (WHR) measured from 1992 to 1994 among different age and gender groups, as well as to test if alcohol consumption or smoking (measured in 1990) would mediate any of the relationships found. RESEARCH METHODS AND PROCEDURES: Data from the Swedish Adoption/Twin Study of Aging (n = 1392; average age: 58 years for middle-aged group and 74 years for older group; 58% female) were analyzed using a maximum-likelihood regression model where age, gender, and age by gender effects were assessed. RESULTS: Cynicism and anxiety predicted WHR in middle-aged subjects regardless of gender. Cynicism explained 2.5% of the variance in WHR and anxiety explained 1.7% of the variance in WHR. Anger predicted WHR in males regardless of age, explaining 4.0% of the variance; depression predicted WHR only in middle-aged females, explaining 2.0% of the variance. All analyses adjusted for body mass index, and neither alcohol consumption or smoking status mediated the relationships. DISCUSSION: These findings are suggestive with regard to the hypotheses that certain psychological states and behaviors may be associated with increased abdominal fatness.  相似文献   
109.
BACKGROUND: Obesity is influenced by genetic and environmental factors. Additionally, synergistic effects of genes and environments may be important in the development of obesity. OBJECTIVE: The aim of this study was to test for genetic effects on food consumption frequency, food preferences, and their interaction with subsequent weight gain. DESIGN: Complete data on the frequencies of consumption of 11 foods typical of the Swedish diet were available for 98 monozygotic and 176 dizygotic twin pairs aged 25-59 y who are part of the Swedish Twin Registry. The data were collected in 1973 as part of a questionnaire study. Body mass index was measured in 1973 and again in 1984. RESULTS: There was some evidence that genetic effects influenced the frequency of intake of some foods. Similarity among monozygotic twins exceeded that among dizygotic twins for intake of flour and grain products and fruit in men and women, intake of milk in men, and intake of vegetables and rice in women, suggesting that genes influence preferences for these foods. Analyses conducted for twins reared together and apart also suggested greater monozygotic than dizygotic correlations, but cross-twin, cross-trait correlations were all insignificant, suggesting that the genes that affect consumption frequencies are not responsible for mediating the relation between the frequency of intake and weight change. CONCLUSIONS: Genetic effects and the frequency of intake are independently related to change in body mass index. However, there was no suggestion of differential genetic effects on weight gain that were dependent on the consumption frequency of the foods studied.  相似文献   
110.
Organochlorines are persistent lipophilic compounds that accumulate in Inuit people living in circumpolar countries. Organochlorines accumulate as a result of the Inuits' large consumption of sea mammal fat; however, available data are limited to blood lipids, milk fat, and adipose tissue. We report results of organochlorine determination in liver, brain, omental fat, and subcutaneous abdominal fat samples collected from deceased Greenlanders between 1992 and 1994. Eleven chlorinated pesticides and 14 polychlorinated biphenyl congeners were measured in tissue lipid extracts by high-resolution gas chromatography with electron capture detection. Mean concentrations of polychlorinated biphenyls, 2, 2'-bis(4-chlorophenyl)-1,1-dichloroethylene, ss-hexachlorocyclohexane, hexachlorobenzene, mirex, trans-nonachlor, and oxychlordane in adipose tissue samples from Greenlanders were 3-34-fold higher than those measured using the same analytical method in samples from Canadians in Quebec City, Quebec. Brain lipids contained lower concentrations of all organochlorines than lipids extracted from other tissues. Organochlorine residue levels in lipid extracts from liver, omental fat, and subcutaneous abdominal fat samples were similar, with the exception of ss-hexachlorocyclohexane, which reached a greater concentration in liver lipids than in lipids from both adipose tissues (4-fold; p < 0. 05). Comparisons with available international data on adipose tissue levels reveal that the organochlorine body burden in the Inuit population of Greenland is presently among the highest resulting from environmental exposure.  相似文献   
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