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991.
992.
We demonstrate the feasibility of using ultra-short echo time (TE = 2 ms) magnetic resonance spectroscopic imaging (MRSI) to detect intracranial mobile lipids in the rat brain. High-performance outer volume suppression and pre-localization were demonstrated in phantoms and by the total absence of signals arising from extra-cranial lipids in MRSI spectra from control rats. The sequence performance was tested on glioma-bearing BDIX rats. Fast-relaxing lipid signals were spatially varied within a glioma during herpes simplex virus thymidine kinase-mediated gene therapy, demonstrating the potential application of this method. 相似文献
993.
Self-reported short or long sleep duration has been repeatedly found to be associated with increased mortality and health risks. However, there is still an insufficient amount of detailed knowledge available to characterize the short and long sleep duration groups in general population. Consequently, the underlying mechanisms potentially explaining the health risks associated with short and long sleep duration are unclear. In the present study, the self-reported sleep duration in a sample of Finnish general population was studied, and its possible associations with such factors as self-perceived health, sociodemographic characteristics, lifestyle, sleep difficulties and daytime concomitants were analyzed. In particular, an effort was made to define mutually statistically-independent determinants of sleep duration. In the Finnish Health 2000 Survey, a representative sample of 8,028 subjects of 30 years of age or older and a sample of 1,894 subjects of 18-29 years of age were invited to take part in the health interview and health examination. The participation rate of the study was over 80%. The most important and statistically-independent determinants of short and long sleep duration were gender, physical tiredness, sleep problems, marital status, main occupation and physical activity. However, in the multivariable model they only accounted for approximately 16% of the variance in sleep duration in short and long sleepers, suggesting multiple sources of variance. The present study also suggests a dose-response like relationship between the sleep duration and many of its determinants within both short and long sleepers. A more detailed analysis of the clinical status of the short and long sleep duration groups is needed to evaluate the possible importance of these findings for health risks associated with sleep duration. 相似文献
994.
Pesonen AK Räikkönen K Strandberg TE Järvenpää AL 《Journal of pediatric psychology》2006,31(3):331-336
Objective To study whether infant weight for gestational age,and gestational age predict mother- and father-rated infanttemperament (IBQ) at 6 months. Methods The sample comprisedof family units with both biological parents and infants bornat term (n = 152). Data on weight and gestational age were collectedform obstetric database. Results Infants born small for gestationalage (SGA) (weight < 10th percentile for gestational age)were rated by both parents as significantly more fearful andnegatively reactive compared to infants born appropriate forgestational age (AGA). Infants born SGA defined by using thelowest 15th or 20th percentile groups did not differ from AGAgroup in temperament. The weekly continuum of gestational agepredicted differences in parental ratings of infant temperamentalattentiveness. Conclusions The predictive significance of infantweight for gestational age and gestational age for behavioraloutcomes appear true also for infants born at term. Concordancein parental perceptions of an infant born SGA emphasizes theclinical significance of the findings. 相似文献
995.
Tryptophan catabolism activated by the indoleamine 2,3-dioxygenase (EC 1.13.11.42) (IDO) enzyme in antigen presenting cells has a central role in induction of mechanisms suppressing T cell activation or clonal expansion. There is evidence suggesting that IDO activity is mainly upregulated by typical Th1-differentiating signals such as interferon-gamma and bacterial lipopolysaccharide (LPS). Therefore, we hypothesized that IDO activity would be lower in a Th2-associated disease such as atopy and that it would be higher in the presence of environmental factors known to favor Th1 differentiation. Here we show that this was the case. Concentrations of tryptophan (trp) and kynurenine (kyn), the main metabolite, were determined by reverse phase liquid chromatography from serum samples of a cohort of 392 non-asthmatic individual of whom 149 were atopics (one or more positive skin test when tested with a panel of 22 allergens). Kyn/trp ratio, as an indicator of IDO activity, was significantly lower in atopic than in non-atopic individuals. The cohort was stratified according to two known atopy-protecting factors, presence of antibodies against Helicobacter pylori or anamnestic information about childhood on a farm environment. As expected, IDO activity was significantly higher in their presence than absence. 相似文献
996.
Valtonen H Suominen K Partonen T Ostamo A Lönnqvist J 《Journal of affective disorders》2006,90(2-3):201-207
BACKGROUND: The association of mental disorders with time patterns of attempted suicide is poorly understood. METHODS: The study material consisted of all consecutive suicide attempts admitted to health care in Helsinki during a one-year period from 15 January 1997 to 14 January 1998. Clinical diagnosis was made according to ICD-10. RESULTS: Overall, the rate of suicide attempts varied markedly during the study period, peaking in autumn and being lowest during winter. Substance use disorders best explained suicide attempts occurring at weekends. There was considerable temporal variation among patients with mood disorders, compared to only slight variation among patients with schizophrenia spectrum disorders. Study subjects tended to contact health services in the late evening and around midnight. Those contacting health services outside normal hours received psychiatric consultation less frequently than others and were referred to aftercare less often. LIMITATIONS: Structured Clinical Interviews for DSM-IV Axis I and II Disorders were not used. CONCLUSIONS: There were marked time patterns of attempted suicide, especially among patients with mood disorders and substance use disorders. This contrasted with the limited fluctuation among patients with schizophrenia spectrum disorders. Contacts with the health care system occurred most often in the late evening and around midnight. The findings question the adequacy of staff numbers for psychiatric consultations and of time to plan aftercare. 相似文献
997.
The monoclonal antibody ED2 is widely used to define macrophages (mphi) in the rat. We have recently identified the ED2 antigen as the rat CD163 glycoprotein. CD163 is a member of the scavenger receptor cysteine-rich group B (SRCR-B) family and functions as a scavenger receptor for hemoglobin-haptoglobin complexes. Moreover, CD163 has also been indicated as a marker for alternatively activated mphi. In the current study, we identify rat CD163/ED2-antigen as a marker for mature tissue mphi. Rat CD163 is constitutively expressed on most subpopulations of mature tissue mphi, including splenic red pulp mphi, thymic cortical mphi, Kupffer cells in the liver, resident bone marrow mphi and central nervous system perivascular and meningeal mphi, but is apparently absent from monocytes. Rat CD163 expression can be promoted by glucocorticoids, and this can be further enhanced by IL4. Finally, engagement of rat CD163 on peritoneal mphi induces the production of pro-inflammatory mediators, including NO, IL-1beta, IL-6 and TNF-alpha. Collectively, our findings identify rat CD163 as a broadly expressed macrophage scavenger receptor that may play a role in the activation of mphi during hemolytic and/or inflammatory conditions. 相似文献
998.
Heponiemi T Elovainio M Pekkarinen L Noro A Finne-Soveri H Sinervo T 《Journal of occupational health psychology》2006,11(2):157-168
This study examined the moderating effect of employee hostility on the association of unit-level resident characteristics (depression and behavioral problems) to individual-level employee's resident-related stress and psychological well-being during 1-year follow-up study among 501 employees in elderly care. Our results showed that employee hostility was associated with decreased psychological well-being. In addition, hostility moderated the association between unit-level proportion of depressive residents and resident-related stress experienced by the individual employees. Hostile employees reported increased resident-related stress irrespective of the proportion of depressed residents in the unit. Instead, nonhostile employees were sensitive to the depression in the unit. They reported low levels of stress when depression levels in the unit were low and increased stress when depression levels were high. 相似文献
999.
Vuorimaa T Virlander R Kurkilahti P Vasankari T Häkkinen K 《European journal of applied physiology》2006,96(3):282-291
This study investigated acute changes in muscle activation and muscular power performance after three different running exercises
in elite long-distance runners. Twenty-two nationally and internationally ranked long-distance runners performed first an
incremental treadmill running test until exhaustion (MR) and then 40 min continuous (TR) and intermittent (2 min run/2 min
rest) (IR) running exercises at an intensity of 80 and 100% of the velocity associated with VO2max, respectively. Muscle activation and muscular power performance tests (counter-movement jumps, CMJ, and a set of ten maximal
half squats from the static starting position with an extra load of 35% of the subjects,′ one repetition maximum) were performed
before and immediately after the runs. The average mechanical power (P) of the half squats was calculated and the root mean square electromyogram (EMGrms) from the vastus lateralis, vastus medialis,
gastrocnemius and biceps femoris muscles was recorded simultaneously during the half squat performances. The results showed
an acute exercise–induced increase in P (ANOVA time effect, P=0.000) together with a reduction in EMGrms of the knee extensor muscles (ANOVA time effect, P=0.000). However, mechanical P expressed as a relative change within the set decreased after MR. In TR the improvement in P correlated positively with the maximal running performance of the runners (P<0.05), while in IR it correlated negatively (P<0.05). Jumping performance was significantly enhanced after each run (P<0.001, for all) and the improvement correlated negatively with the maximal sprinting speed and maximal jumping height of
the runners (P<0.01, for all). It is concluded that in elite long distance runners an intensive prolonged running exercise reduces the surface
EMG of the knee extensor muscles, and may lead to a different coordination strategy in leg extension exercises performed into
the vertical direction. After continuous type of running the power improvement correlates positively with maximal endurance
running capacity, whereas after intermittent type of running it correlates negatively. 相似文献
1000.