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101.
102.
Psychometric Properties of Resting Anterior EEG Asymmetry: Temporal Stability and Internal Consistency 总被引:7,自引:0,他引:7
Andrew J. Tomarken Richard J. Davidson Robert E. Wheeler Linda Kinney 《Psychophysiology》1992,29(5):576-592
We examined whether resting anterior electroencephalographic (EEG) asymmetry in the alpha frequency band has psychometric properties that would be expected of a measure assessing individual differences. In each of two experimental sessions, separated by three weeks, resting EEG in midfrontal and anterior temporal sites was recorded from 85 female adults during eight 60-s baselines. Resting alpha asymmetry demonstrated acceptable test-retest stability and excellent internal consistency reliability. Analyses including other frequency bands indicated that degree of stability varied somewhat as a function of band and region. In addition, asymmetry was less stable than absolute power. Discussion focuses on the implications of the present findings for the measurement and conceptualization of resting anterior asymmetry. 相似文献
103.
Vignozzi L Vannelli GB Morelli A Mancina R Marini M Ferruzzi P Crescioli C Luconi M Donati S Fisher AD Baldi E Filippi S Forti G Maggi M 《Molecular human reproduction》2005,11(2):99-106
Although abnormalities of the male external genitalia (MEG) are a relatively common problem, little is known concerning the molecular mechanisms that finely regulate penile development. We report here the expression of the oxytocin receptor (OTR) gene by real-time RT-PCR in human fetal tissues (11th-12th week of gestation), including the MEG. The developing penis expressed a very high level of OTR mRNA, only a half log(10) unit lower than fetal central nervous system, used as a positive control. The OTR protein is also highly expressed (western, immunohistochemistry and binding studies) and immunolocalized both in the mesenchymal body and in the surrounding blood capillaries, which will later constitute penile trabeculae and sinusoids. Binding studies using [125I]oxytocin antagonist ([125I]OTA) in cultured human fetal penile smooth muscle cells (hfPSMC) revealed the presence of specific OTR with a high capacity and affinity for oxytocin (OT) and for OTA. Increasing concentrations of OT dose-dependently induced intracellular Ca2+ mobilization. Furthermore, OTR mediated an increase in the proliferation and the migration of hfPSMC. In conclusion, we demonstrate that in the developing human MEG, OTR is highly expressed and might be involved in coordinating timely and appropriate proliferation and migration of the penile cells. Thus, OTR might represent an additional target for investigating human fetal MEG organogenesis. 相似文献
104.
105.
Alfred C. deCiutiis Charles M. Peterson Margaret J. Polley Linda J. Metakis 《Journal of the National Medical Association》1978,70(7):503-506
Total hemolytic complement activity (CH50), immuno-electrophoretic conversion of Factor B (C3PA), and of C3 were studied in 16 patients with sickle cell disease in a steady state, eight patients in crisis, and ten patients with β-thalassemia major anemia maintained on a constant transfusion regimen. Patients with sickle cell disease in a steady state have moderatley 56 (percent) depressed conversion of Factor B in addition to markedly decreased conversion of C3 in four of ten patients. One of the three sickle cell patients and two of the four thalassemia patients with low C3 conversion levels have died subsequent to the studies. The combination of chronically decreased Factor B conversion in the face of markedly decreased C3 conversion may make these patients occasionally vulnerable to overwhelming infection analagous to the situation seen in postsplenectomy cases. 相似文献
106.
Soy isoflavones, body composition, and physical performance 总被引:2,自引:0,他引:2
OBJECTIVES: Physiologic changes, occurring during the process of aging, can have serious health consequences, such as increased risk of chronic disease and disability. Decline in estradiol levels after menopause is hypothesized to contribute to this risk. Thus, hormone therapy (HT) might prevent or delay those changes. However, HT has serious side effects and alternative approaches are needed. METHODS: We performed a 12-month double-blind randomized trial comparing soy protein containing 99mg isoflavones (aglycone weights) with milk protein (placebo) daily in 202 postmenopausal women aged 60-75 years. Endpoints were body composition, and physical performance. Randomization resulted in reasonable well-balanced groups, 153 (76%) women completed the trial. Compliance was good (plasma genistein levels 55 +/- 101 and 1259 +/- 1610 nmol/L for placebo and soy group, respectively). The changes in the endpoints during the intervention period among the two intervention groups were analyzed. RESULTS: Body mass index (BMI) and waist-to-hip ratio did not change during intervention. Handgrip strength at the final visit was slightly worse in the soy group compared to the placebo group (-0.45 kg (95% C.I.: -2.5, 1.6 kg; p = 0.7), but this difference was not statistically significant. Self-reported functional status, mobility and physical performance, all slightly improved during intervention but there were no differences between the groups. CONCLUSIONS: The results of the present trial do not support the view that soy isoflavones have favorable effects on body composition and physical performance in postmenopausal women. 相似文献
107.
Linda M. Gerber Joseph E. Schwartz Peter L. Schnall Thomas G. Pickering 《American journal of human biology》1995,7(2):173-182
The extent to which the relationship between body fat and blood pressure either differs by sex or explains sex differences in blood pressure is examined. Estimates of the relationship of blood pressure to several measures of adiposity in men and women were obtained from a systematic review of the literature and tests of whether these relationships differ by sex were performed. Analysis of covariance (controlling for age and race) was used for both casual and ambulatory blood pressure in the Cornell Worksite Blood Pressure Study (N = 276). In general, most adiposity measures were significantly related to casual and ambulatory blood pressure in men and women. Subscapular skinfold thickness and body mass index exhibited the strongest associations. The vast majority of adiposity/blood pressure associations were not significantly different for men and women. Finally, sex differences in adiposity did not account for much of the sex difference observed in blood pressure. © 1995 Wiley-Liss, Inc. 相似文献
108.
Jensen J Brennesvik EO Bergersen H Oseland H Jebens E Brørs O 《Pflügers Archiv : European journal of physiology》2002,444(1-2):213-219
In the present study, the density of cell surface beta-adrenergic receptors was determined in different skeletal muscles using the hydrophilic ligand [3H]CGP 12177. The density of beta-adrenergic receptors was highest in the slow-twitch soleus muscle (32.8+/-0.9 fmol mg dw(-1)) and lowest in the fast-twitch glycolytic white gastrocnemius (10.4+/-0.5 fmol mg dw(-1)) beta-Adrenoceptor density correlated closely with the percentage of type-I fibres (r=0.979; P<0.0001) and inversely with the percentage of type-IIB fibres (r=696; P<0.03). Incubation with isoprenaline (10 microM) for 30 min decreased the density of beta-adrenergic receptors in the cell surface from 32.9+/-0.8 to 19.3+/-0.7 fmol mg dw(-1) in the soleus and from 16.8+/-1.0 to 12.0+/-0.7 fmol mg dw(-1) in the epitrochlearis. Internalisation appeared rapid (half-time less than 5 min). To study externalisation of beta-adrenergic receptors, soleus strips were incubated 30 min with 10 microM isoprenaline and then transferred to buffer without agonist. The first incubation reduced the density to approximately 50%, the subsequent incubation without agonist increased cell surface receptor density to approximately 80% of the initial density after 1 h. No further increase was observed over the next 2 h, suggesting that some of the receptors had been degraded. Insulin or contractile activity did not influence rate of externalisation. 相似文献
109.
Shankaran S Laptook AR Ehrenkranz RA Tyson JE McDonald SA Donovan EF Fanaroff AA Poole WK Wright LL Higgins RD Finer NN Carlo WA Duara S Oh W Cotten CM Stevenson DK Stoll BJ Lemons JA Guillet R Jobe AH;National Institute of Child Health Human Development Neonatal Research Network 《The New England journal of medicine》2005,353(15):1574-1584
110.