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11.
Striatal dopamine transporter density in major depression   总被引:4,自引:0,他引:4  
Rationale: There are no previous data available regarding [123I]β-CIT binding to the dopamine transporter sites in the basal ganglia in depressed patients. Objective: The present study tested the hypothesis that the brain DAT density in depressed patients is lower than that in matched healthy controls. Methods: Fifteen drug-naive outpatients with major depression and 18 healthy controls were investigated using single photon emission computerized tomography (SPECT) with a high-affinity dopamine transporter specific radioligand, 123I-labeled β-CIT (2β-carbomethoxy-3β-(4-iodophenyl)-tropane). Results: We found a significantly higher [123I]β-CIT uptake in both sides of the basal ganglia in patients with major depression than in the controls (Mann-Whitney U-test, P = 0.002 on the right and P = 0.003 on the left). Conclusions: The radioligand uptake reflecting the DAT density was significantly higher among the patients than in the controls. This finding is unexpected, since it is generally believed that monoaminergic neurotransmission is lower in depression, and therefore it could be assumed that a reduction in dopamine transmission would lead to secondary down-regulation of DAT density. However, it is possible that up-regulation of the DAT may be the primary alteration, which leads to lower intrasynaptic dopamine concentration and to lower dopamine neural transmission. Received: 20 October 1998/Final version: 25 January 1999  相似文献   
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ABSTRACT Objective: This study describes workplace centered activities performed by occupational health professionals, as well as difficulties linked to workplace centered activities, cooperation with client workplaces, and participation both in risk assessment and in the development of working environment.
Design: The design is a cross-sectional prevalence study.
Sample: The questionnaires were sent to 250 occupational health professionals, of whom 176 (70%) returned the completed forms and of whom 99% were nurses.
Measurements: Their activities, difficulties, cooperation, and participation in risk assessment and development of safe and healthy working conditions.
Analytic strategy: The data were analyzed by using frequencies, means, 1-way ANOVA, and the Kruskal-Wallis test.
Results: Workplace focused activity hours were mainly spent on risk assessment and counseling. One workplace visit took approximately 4 hr. The greatest difficulties were encountered with participation in development projects and in monitoring the effectiveness of improvement activities, especially in health care centers. Occupational health nurses cooperated with client enterprises and participated in risk assessment more often than the other occupational health professionals. Also workplace representatives participated actively in risk assessment. The most difficult modules were considered to be the risk assessment of chemicals, biological factors, and perceived stress, this being especially so in health care centers.
Conclusions: It is essential that occupational health professionals visit more often in their client enterprises and improve their skills in preventing harms caused by chemical and biological factors, and perceived stress.  相似文献   
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Blood O2 carrying capacity affects aerobic capacity (VO2max). Patients with type 1 diabetes have a risk for anaemia along with renal impairment, and they often have low VO2max. We investigated whether total haemoglobin mass (tHb-mass) and blood volume (BV) differ in men with type 1 diabetes (T1D, n = 12) presently without complications and in healthy men (CON, n = 23) (age-, anthropometry-, physical activity-matched), to seek an explanation for low VO2max. We determined tHb-mass, BV, haemoglobin concentration ([Hb]), and VO2max in T1D and CON. With similar (mean ± SD) [Hb] (144 vs. 145 g l?1), T1D had lower tHb-mass (10.1 ± 1.4 vs. 11.0 ± 1.1 g kg?1, P < 0.05), BV (76.8 ± 9.5 vs. 83.5 ± 8.3 ml kg?1, P < 0.05) and VO2max (35.4 ± 4.8 vs. 44.9 ± 7.5 ml kg?1 min?1, P < 0.001) than CON. VO2max correlated with tHb-mass and BV both in T1D (r = 0.71, P < 0.01 and 0.67, P < 0.05, respectively) and CON (r = 0.54, P < 0.01 and 0.66, P < 0.001, respectively), but not with [Hb]. Linear regression slopes were shallower in T1D than CON both between VO2max and tHb-mass (2.4 and 3.6 ml kg?1 min?1 vs. g kg?1, respectively) and VO2max and BV (0.3 and 0.6 ml kg?1 min?1 vs. g kg?1, respectively), indicating that T1D were unable to reach similar VO2max than CON at a given tHb-mass and BV. In conclusion, low tHb-mass and BV partly explained low VO2max in T1D and may provide early and more sensitive markers of blood O2 carrying capacity than [Hb] alone.  相似文献   
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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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Background/Aims: To examine whether intestinal bacterial translocation occurs early in acute mild and severe pancreatitis and whether the intestinal expression of tight junction proteins (claudins-2, -3, -4, -5, -7), apoptosis or proliferation would explain the possible translocation. Methodology: Fifteen pigs were randomized to controls (n=5) or to develop mild edematous pancreatitis (n=5, saline infusion to pancreatic duct) or severe necrotic pancreatitis (n=5, taurocholic acid infusion). Translocation was studied by measuring bacterial cultures from portal vein blood and mesenteric lymph nodes. Immunohistochemical expression of the tight junction proteins, apoptosis rate (TUNEL) and Ki-67 were analyzed quantitatively from the epithelium of the jejunum and colon. Results: There was no bacterial translocation during the 6 hours followup, nor changes in the expression of tight junction proteins claudins-2 and -5 in jejunum or colon. Saturation and proportional area of claudin-3 staining decreased in the colon, as did claudins-4 and -7 staining in the jejunum of the necrotic pancreatitis group. Increased apoptosis was found in all samples from controls and the edematous pancreatitis group but not in jejunum in the necrotic pancreatitis group. Ki-67 activity tended to increase in the upper half of the villus in edematous and necrotic pancreatitis. There were no changes in the basic histology. Conclusions: The major finding of this study was that bacterial translocation from the gut is not present at the beginning of acute pancreatitis. Tight junction proteins claudin-2 and -5 do not become altered in the early stages of pancreatitis. Claudin-3 decreases in the colon and claudins-4 and -7 in the jejunum in necrotic pancreatitis. Laparotomy itself causes increased apoptosis in the colon and the jejunum.  相似文献   
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Background

The aim of this study was to compare three different methods to cover excised burn wounds in a randomized controlled trial.

Methods

Fascially excised burn wounds, measuring 10 cm × 5 cm, were covered with Integra®, split thickness skin graft (STSG), and a viscose cellulose sponge Cellonex™ in each of ten adult patients. Integra® and Cellonex™ treated areas were covered with thin STSG on day 14. Biopsies were taken 3, 7, 14, and 21 days, 3 months, and 12 months after surgery, and samples were subjected to a range of immunohistochemical stains, in addition to hematoxylin and eosin (HE). Scar assessment was performed 3 and 12 months post-operatively with the Vancouver Scar Scale (VSS).

Results

Inflammation was not substantial in any of the study areas, but Cellonex™ had the most neutrophils, histiocytes, and lymphocytes with significant differences on days 7 and 14. Complete vascularization of Integra® seemed to occur later compared to the other materials. STSG had the most myofibroblasts on day 14 (p = 0.012). In VSS the quality of the scar improved in all materials from 3 to 12 months.

Conclusions

The final results for all treatments after 12 months demonstrate equal clinical appearance, as well as histological and immunohistochemical findings.  相似文献   
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