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M Carlier E Spitz MC Vacher-Lavenu P Villéger B Martin F Michel 《Canadian Metallurgical Quarterly》1996,26(4):409-407
Manual performance, direction, and degree of laterality were tested in monozygotic (MZ) twins (8-12 years old) of known chorion type and dizygotic (DZ) twins. Three manual tasks rarely employed in twin studies were used; dot-filling, tapping, and peg-moving tasks. No chorion effect was observed: the monochorionic and dichorionic MZs differed neither for frequency of discordant pairs nor for handedness, laterality measurements, and manual performance. The pooled MZs and DZs were then compared in a classic twin design. The within-pair resemblance was not higher in MZs than in DZs for variables measuring level of manual performance. For laterality scores intraclass correlations were close to zero in MZ and DZ twin groups. 相似文献
73.
PH van der Meide MC de Labie SR Ruuls RJ Groenestein CA Botman T Olsson CD Dijkstra 《Canadian Metallurgical Quarterly》1998,84(1):14-23
BACKGROUND: It is important for HIV/AIDS control programmes to determine population knowledge on AIDS in order to develop appropriate Information, Education and Communication (IEC) messages. The objectives of our study were to determine the seroprevalence of HIV and syphilis among pregnant women, female prostitutes and long-distance truck drivers and to evaluate knowledge, attitudes, beliefs, and practice (KABP) with respect to the HIV/AIDS epidemic in these three groups in Burkina Faso. METHODS: We performed three cross-sectional serosurveys including face-to-face interviews on KABP between October 1994 and February 1995 in three population groups. RESULTS: Overall, 1,294 pregnant women, 236 long-distance truck drivers and 426 female prostitutes were recruited. HIV seroprevalence was 8% (95% Confidence Interval (CI): 6.6-9.6) among pregnant women, 18.6% (95% CI: 13.9-24.2) among long-distance truck drivers and 58.2% (95% CI: 53.4-62.9) in female prostitutes. The prevalence of syphilis was 2.5%, 9.3% and 15%, respectively. Most pregnant women (98%), long-distance truck drivers (96%) and female prostitutes (98%) had already heard of AIDS. However, the level of knowledge of HIV transmission routes, of risk factors for HIV transmission and of available preventive measures was very low. Consequently, 41% of pregnant women, 40% of long-distance truck drivers and an alarming 61% of female prostitutes reported that they did not feel themselves at risk for HIV. In each group, high levels of knowledge on AIDS were associated with increased awareness of AIDS risk and the adoption of preventive behaviours. Level of education was associated with knowledge of AIDS and condom use. However, in the 12 months preceding the surveys, condom use was very low among pregnant women (0.1%), long-distance truck drivers (18%) and among female prostitutes (42%). CONCLUSIONS: These results indicate that HIV is widespread in Burkina Faso and that there is an urgent need to develop and evaluate HIV prevention strategies in the general population and among core groups such as female prostitutes and long-distance truck drivers. Interventions must include information campaigns, condom promotion and distribution, and sexually transmitted diseases control. 相似文献
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The present study was aimed at comparing the effects of serotonin (5-HT) synthesis blockade using chronic administration of p-chlorophenylalanine (PCPA) and 5,7-dihydroxytryptamine injections of variable volume (3 vs. 6 microl) on the density of NPY immunoreactive (Ir) neurons and binding of [3H]8-OH-DPAT, S-CM-G[125I]TNH2 and [125I]DOI to 5-HT1A, 5-HT1B/1D, and 5-HT2A/2C receptors in rat cortical regions. Three weeks after large but partial (89% depletion in 5-HT tissue concentration) lesions of 5-HT neurons no changes in neither NPY immunoreactivity nor 5-HT receptor binding were detected. The complete 5,7-DHT lesions produced increases in the number of NPY-Ir neurons in the upper regions of the cingular (134%), frontal (140%) and parietal cortex (48%) and corresponding decreases in 5-HT2A/2C binding (16-26%). No changes in 5-HT1A and 5-HT1B/1D binding were observed after lesions of this kind. After PCPA treatment, decreases in NPY-Ir neurons density (22-40%) and increases in 5-HT1A and 5-HT1B/1D receptor binding sites (20-50%) were distributed in both upper and deeper cortical regions. The lack of effect of the partial lesion suggests that spared 5-HT neurons may exert compensatory mechanisms up to a large extent. The changes in NPY immunoreactivity and 5-HT2A/2C binding detected in the upper regions of the cortex after complete 5-HT lesions probably result from local cellular rearrangements, whereas blocking 5-HT synthesis has more widespread influence on NPY neurons and on 5-HT1A and 5-HT1B/1D receptor subtypes. Moreover, decreases in DOPAC concentrations detected only after complete lesions suggest that the involvement of catecholaminergic transmission may also differentiate 5,7-DHT and PCPA treatments. Altogether, these data suggest that different receptor subtypes might be involved in 5-HT-NPY relationships. 相似文献
76.
MJ González-Corbella MC López-Sabater AI Castellote-Bargalló C Campoy-Folgoso M Rivero-Urgell 《Canadian Metallurgical Quarterly》1998,52(11):813-818
OBJECTIVE: To assess the effect of long-chain polyunsaturated fatty acids (LCPUFA)- and vitamin E-supplemented formula feeding on erythrocyte and plasma alpha-tocopherol (VE), and plasma retinol (VA) concentrations in neonates and to compare these values with those found in infants feeding on infant formula without LCPUFA or breast milk SETTING: University Hospital of Granada, Spain. SUBJECTS: 49 full-term infants. DESIGN AND INTERVENTION: Subjects who chose not to breast feed were fed either (i) unsupplemented infant formula (F) or (ii) infant formula supplemented with LCPUFA and vitamin E (FL). Alpha-tocopherol and retinol were measured at 7 days, 1 month and 3 months. RESULTS: Plasma and erythrocyte VE concentrations and plasma VE/total lipids ratio increased significantly in all groups at 1 month of life (P < 0.05), but did not change significantly between 1 month and 3 months in any group (P > 0.05). Erythrocyte VE and VA retinol concentrations were higher in infants fed an infant formula than in breast milk-fed infants at 1 month of life (P < 0.05). Finally, there were no significant differences in plasma or erythrocyte VE levels, plasma VA or plasma VE/total lipid ratio between any groups at 3 months of life (P > 0.05). CONCLUSION: Infants fed on LCPUFA- and vitamin E-supplemented infant formula for 3 months have similar vitamin E and A status to infants fed on breast milk or infant formula without LCPUFA supplementation. 相似文献
77.
H Baumgartner G Porenta YK Lau M Wutte U Klaar M Mehrabi RJ Siegel J Czernin G Laufer H Sochor H Schelbert MC Fishbein G Maurer 《Canadian Metallurgical Quarterly》1998,32(6):1701-1708
OBJECTIVES: We examined the relationship among viability assessment by dobutamine echocardiography (DE), positron emission tomography (PET) and thallium-201 single-photon emission computed tomography (TI-SPECT) to the degree of fibrosis. BACKGROUND: DE, PET and TI-SPECT have been shown to be sensitive in identifying viability of asynergic myocardium. However, PET and TI-SPECT indicated viability in a significant percentage of segments without dobutamine response or functional improvement after revascularization. METHODS: Twelve patients with coronary artery disease and severely reduced left ventricular function (EF 14.5+/-5.2%) were studied with DE prior to cardiac transplantation: 5 had additional PET and 7 had TI-SPECT studies. Results of the three techniques were compared to histologic findings of the explanted hearts. RESULTS: Segments with >75% viable myocytes by histology were determined to be viable in 78%, 89% and 87% by DE, PET and TI-SPECT; those with 50-75% viable myocytes in 71%, 50% and 87%, respectively. Segments with 25-50% viable myocytes showed response to dobutamine in only 15%, but were viable in 60% by PET and 82% by TI-SPECT. Segments with <25% viable myocytes responded to dobutamine in 19%; however, PET and TI-SPECT demonstrated viability in 33% and 38%, respectively. Discrepant segments without dobutamine response but viability by PET and SPECT had significantly more viable myocytes by pathology than did those classified in agreement to be nonviable but had significantly less viable myocytes than those classified in agreement to be viable (p < .001). CONCLUSIONS: These findings suggest that contractile reserve as evidenced by a positive dobutamine response requires at least 50% viable myocytes in a given segment whereas scintigraphic methods also identify segments with less viable myocytes. Thus, the methods may provide complementary information: Nuclear techniques appear to be highly sensitive for the detection of myocardial viability, and negative tests make it highly unlikely that a significant number of viable myocytes are present in a given segment. Conversely, dobutamine echo may be particularly useful for predicting recovery of systolic function after revascularization. 相似文献
78.
F Herencia A Ubeda ML Ferrándiz MC Terencio MJ Alcaraz M García-Carrascosa R Capaccioni M Payá 《Canadian Metallurgical Quarterly》1998,62(9):PL115-PL120
The effects of dichloromethane and methanol extracts from the marine invertebrates Leptogorgia ceratophyta, Holothuria tubulosa, Coscinasterias tenuispina and Phallusia fumigata on carrageenan-induced paw oedema in mice were investigated. The dichloromethane extract of Coscinasterias tenuispina and the methanol extract of Holothuria tubulosa administered p.o. at 50, 100 and 150 mg/kg, inhibited oedema in a dose-dependent manner 3 h after administration of carrageenan. Both extracts partially decreased elastase activity and PGE2 levels measured in homogenates from inflamed paws, without affecting the levels of this prostanoid present in stomach homogenates. As observed with the selective inhibitor NS398, both extracts can decrease cyclo-oxygenase activity in inflamed tissues but do not modify the constitutive cyclo-oxygenase enzyme. Therefore, these extracts represent new marine resources for the isolation of novel agents active on inflammatory conditions. 相似文献
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80.