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41.
Sub-cellular studies of transmissible spongiform encephalopathies (TSEs) have been carried out on several animal species and human beings. However, studies of optimal perfusion-fixed tissues have largely been confined to examination of rodents. Using a recently developed technique, heads of scrapie-affected sheep and controls were perfusion fixed with mixed aldehydes. The obexes were immunohistochemically labelled with PrP antibodies, and the dorsal motor nucleus of the vagal nerve was examined by electron microscopy. Irregular neuritic profiles with highly invaginated membranes, associated with coated pits were found in all scrapie-affected sheep, but not in controls. Interestingly, they were consistently more frequent in the homozygous A(136) sheep. This is the first report describing sub-cellular differences in pathology associated with different PrP genotypes. Rarely, amorphous material, or sparse fibrillar structures, were present in the extracellular space. The changes were often associated with irregular plasmalemma and frequent coated pits. Vacuolation typical of TSEs, dystrophic neurites and variable gliosis were present. Herniation of membranes and organelles from apparently healthy processes into adjacent vacuoles and dendrites was also observed. We suggest that the increase in coated pits and plasmalemma invagination is related to an attempted internalisation of aggregated disease-specific PrP, or protofilaments, from the extracellular space. 相似文献
42.
Measuring health complaints by administrating a single report is common. Our aim was to assess variation in pain and other subjective complaints over an extended period, whether a single-sample produces representative data, and determine associations between complaints. Health-complaint reports were collected from postal workers at monthly intervals over a period of 32-34 consecutive months (1997-2000). We computed six compound complaint-severity indices of 30 complaint-severity scores (intensity score x duration score, scale 0-9). In 67% of the scores, the complaints exhibited larger deviation from a reference (12 consecutive reports in the last 24 months of the study period) when using one report from the respective reference period compared with the mean of two consecutive reports. Four consecutive samples were needed to obtain agreement for 95% of the data when the criterion of accepted deviation from the reference was set to +/-1.0. Neither inspection of graphs nor statistical tests revealed any seasonal pattern or trend on either a group or individual level. The musculoskeletal and psychological complaint-severity indices correlated strongly (rs > 0.66). Correlations between the different somatic indices were generally weak or moderate (rs < 0.55). The initial report produced higher complaint ratings than subsequent reports did. Due to large intra-individual complaint variability and higher complaint-severity level exhibited on the initial report compared to those that followed, measuring subjective health with a single-sample approach does not produce data representativeness for average complaints over a period. More than two samples should be collected when the purpose is to reveal changes in health. 相似文献
43.
Vajda F Lander C O'brien T Hitchcock A Graham J Solinas C Eadie M Cook M 《Epilepsia》2004,45(11):1466-1466
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BACKGROUND: The authors assessed the prognostic significance of abnormal cyclin dependent kinase inhibitor (CDKI) expression in adenocarcinomas of the uterine cervix. METHODS: Population-based, archival material from patients with International Federation of Gynecology and Obstetrics (FIGO) Stage I and II cervical adenocarcionmas from 2 5-year periods (1976-1980, n = 82 patients; 1986-1990, n = 142 patients) was examined for expression of p21(WAF1), p27(Kip1), and p16(INK4/MTS1) using immunohistochemical techniques. RESULTS: Rates of tumors with low levels of nuclear expression of p27 and p16 were lower during the period 1976-1980 (P < 0.01), suggesting bias due to unbuffered formalin. Analyses that were restricted to patients from 1986-1990 showed positive associations between all three CDKIs (P < 0.05). Low p16 expression was associated with higher FIGO stage (P = 0.01), age older than 55 years (P = 0.01), and deep invasion (P = 0.003). No significant associations with stage, age, or histopathologic parameters were found for p21 or p27. Significant associations with tumor differentiation were not seen for any CDKI. Kaplan-Meier plots showed diverging survival curves for p21 and p27 expression, but the differences were not significant. In multivariate analysis, low p27 expression and high p16 expression were strong predictors of a poor prognosis (p27: < 40% nuclear staining; P = 0.001; hazard ratio, 3.18; p16: < 40% nuclear staining; P < 0.001; hazard ratio, 0.16). Low p27 expression was of prognostic significance only if it was analyzed together with p16 expression. Further evaluation indicated that patients with different phenotypic p27/p16 combinations may have different outcomes. CONCLUSIONS: Aberrant expression patterns of CDKIs were predictors of prognosis for patients with FIGO Stage I or II cervical adenocarcinoma. Analysis of CDKI expression in this patient group may prove clinically useful. 相似文献
46.
Florence-Emilie Kinnafick Cecilie Thøgersen-Ntoumani Joan Duda 《Journal of behavioral medicine》2016,39(4):574-586
Few short messaging service (SMS) studies to support behaviour change have used a theoretical underpinning. Using a self-determination theory perspective, we explored the effects of need supportive (NS) SMS on physical activity in 65 (BMI = 24.06 kg/m2, SD = 5.49; M = 25.76 years, SD = 10.23) insufficiently active individuals embarking on an existing exercise programme. For 10 weeks participants were randomised to an intervention group (NS) or control group (neutral). SMS were sent twice weekly, randomly, via an online SMS service. Mixed design ANCOVA and MANCOVA analyses of measures taken at baseline, mid and post intervention revealed increased levels of perceived autonomy support and psychological need satisfaction in the intervention group post intervention. Both groups reported increases in intrinsic motivation from pre to post intervention. Moderate intensity physical activity was greater in the intervention than the control group at 4-month post intervention with control group returning to baseline levels. Findings provide preliminary causal evidence to support the use of NS SMS to optimise physical activity behaviour change in individuals who are insufficiently active. 相似文献
47.
Mark D. Griffiths Cecilie S. Andreassen Ståle Pallesen Robert M. Bilder Torbjørn Torsheim Elias Aboujaoude 《International journal of mental health and addiction》2016,14(6):1107-1110
Manchiraju et al. (International Journal of Mental Health and Addiction, 1–15, 2016) published the Compulsive Online Shopping Scale (COSS) in the International Journal of Mental Health and Addiction (IJMHA). To develop their measure of compulsive online shopping, Manchiraju and colleagues adapted items from the seven-item Bergen Shopping Addiction Scale (BSAS) and its’ original 28-item item pool. Manchiraju et al. did not add or remove any of the original seven items, and did not substantially change the content of any of the 28 items on which the BSAS was based. They simply added the word “online” to each existing item. Given that the BSAS was specifically developed to take into account the different ways in which people now shop and to include both online and offline shopping, there does not seem to be a good rationale for developing an online version of the BSAS. It is argued that the COSS is not really an adaptation of the BSAS but an almost identical instrument based on the original 28-item pool. 相似文献
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49.
Cecilie Javo John A. Rønning Bjørn Helge Handegård Floyd W. Rudmin 《European child & adolescent psychiatry》2009,18(3):154-163
In a community-based birth cohort from Arctic Norway, correlations between parents and teachers on child competence and behavioral
problems were determined for Sami and Norwegian 11–12 year-olds, using as instruments the child behavior checklist (CBCL),
teacher report form (TRF), and the impact supplement of the extended strength and difficulties questionnaire (SDQ). Parent–teacher
correlations on child behavioral problems were generally high in the Norwegian group, but low in the Sami group. Cross-cultural
differences in cross-informant correlations were highest regarding externalizing and attention problems. Parent–teacher correlations
on total impact of child difficulties also differed between the ethnic groups. Once again, a lower correlation was found for
the Sami children. The discrepancy between parents’ and teachers’ perception of problems that needed attention was highest
for the Sami, and lowest for the Norwegians. The Sami parents reported fewer perceived difficulties and less impact of problems
than did the Norwegian parents. In contrast, no ethnic differences emerged for teachers’ ratings. The paper discusses how
cultural norms might influence the reports of child problems. It demonstrates the importance of combining parent and teacher
reports of child behavior problems in minority and indigenous children, who often live under different cultural norms in home
and school contexts. 相似文献
50.
The relation of adult bronchial responsiveness to serious childhood respiratory illness in the ECRHS
BACKGROUND: Respiratory symptoms in adulthood have been found to be associated with childhood respiratory infection, but few studies have analyzed adult bronchial responsiveness (BHR) with adequate adjustment for known risk factors. OBJECTIVE: To estimate the relation of BHR with serious childhood respiratory infections in a large population study. METHODS: The European Community Respiratory Health Survey (ECRHS) was a cross-sectional population-based survey in 34 centers. Data on serious respiratory infections before the age of 5 years and possible confounders were obtained from a questionnaire administered in the clinic. Blood samples were taken for measurement of total immunoglobulin E (IgE) and specific IgE to four common allergens, and spirometry and bronchial challenge with methacholine were performed. A continuous measure of BHR was analyzed by multiple regression, in 11,282 participants, in relation to serious respiratory infection and other potential risk factors, adjusted for center and major determinants of adult BHR. RESULTS: Those reporting a serious childhood respiratory infection had greater BHR, by an amount corresponding to approximately 0.23 doubling doses (95% confidence interval 0.02-0.44) of the amount of methacholine causing a 20% fall (PD(20)) in forced expiratory volume in 1s (FEV(1)). All childhood factors explained less than 0.3% of variation in BHR in addition to over 20% by factors measured in adulthood. The relation of BHR to BMI was confined to smokers. CONCLUSIONS: We found an effect of serious childhood respiratory infection on adult BHR, but this was small in comparison to relations of BHR to IgE-sensitization and airway caliber. 相似文献