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991.
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994.
Kinetics of cadmium decontamination in Lithobius forficatus, performed in autumn experiments showed a decrease in Cd level, from about 30 mg/kg dw at the beginning of the experiment to about 12 mg/kg dw ten weeks later. Kinetics of cadmium contamination in animals showed in a first time a dramatic increase in Cd levels (up to a mean 80 mg/kg dw). Then a regular decrease was observed, although the animals were regularly fed with cadmium contamined larvae. Difference between animals fed or not with cadmium containing diet ranged from 18 mg/kg dw to only 8 mg/kg dw at the end of the experimental series. Experiments conducted either in autumn or in spring showed comparable aspects in the evolution of level curves, if not the same values. Natural decontamination of lead in animals showed results that were not convincing, depending at least of the dose level present in animals. Therefore, when experimental intoxication was performed, a natural detoxification process took place where Pb levels in animals first increased dramatically and then regularly decreased which was assumed to be evidence of an active excretion. Moreover, animals living in an artificially lead polluted soil and fed with lead-free diet also showed a rapid increase in Pb level followed by a plateau. From these studies, it can be concluded that these centipedes can be contaminated both by food intake and by ion regain through the tegument.  相似文献   
995.
To gain an insight into the burden of dementia in an aging society, life expectancy with dementia and its counterpart dementia-free life expectancy (DemFLE) in The Netherlands are presented. Sullivan's method was used to calculate DemFLE. For elderly living either independently or in homes for the elderly prevalence figures on dementia were obtained from the Rotterdam Elderly Study (RES; n = 7528); for elderly in nursing homes the SIG Nursing home Information System was used. Conforming to other authors only the prevalence data on moderate and severe dementia as diagnosed with DSM-III-R criteria are used. The prevalence of mild dementia was not taken into account. At 65 years DemFLE for men is 14.0 years, that is 96.4% of the total life expectancy (14.5 years at this age). At age 90, DemFLE for men is 2.5 years, equal to 77.5% of the total life expectancy (3.3 years). For women DemFLE at age 65 is 17.7 years, that is 93.2% of their life expectancy (19.0 years), and at the age of 90, DemFLE for women is 2.8 years, equal to 74.7% of their remaining life expectancy (3.8 years). The absolute number of years with dementia remains relatively constant with increasing age. About 20–25% of these years with dementia are spent in nursing homes, the other 75–80% living independently. At each age compared with men women have both a higher DemFLE and a higher expectancy of years with dementia. The percentage of life expectancy without dementia however, is always lower for women, because of their higher total life expectancy. This indicates that the burden of dementia in absolute and relative terms is higher for women. Most years with dementia are spent at home, indicating that the burden of dementia rests mainly on the shoulders of informal caregivers.  相似文献   
996.
Mainly located in the skin or mucosa of patients with allergic diseases, eosinophils contribute directly to tissue damage and chronic inflammation. The past year has seen significant advances in the study of the factors involved in the specific tissue recruitment of eosinophils, including chemoattractants and their receptors. New data have been obtained on the synthesis by eosinophils of various cytokines mostly released by immune complexes.  相似文献   
997.
This article examines the effect of war events and pre-war depression on the prevalence of major depression during war. A total of 658 subjects aged 18-65 years were randomly selected from four Lebanese communities differentially exposed to the Lebanon Wars and were interviewed using the Diagnostic Interview Schedule (Arabic version). The individual levels of exposure to war events were assessed through a War Events Questionnaire. The lifetime prevalence of the DSM-III-R-defined major depression varied across the four communities from 16.3 to 41.9%; the final parameters predicting major depression since the onset of the wars were: depression before the wars and exposure to the wars. Both, individual levels of exposure to war and a history of pre-war depression, predict the development of depression during war. Received: 5 June 1997 / Accepted: 14 July 1998  相似文献   
998.
BACKGROUND: Females appear to be more sensitive and responsive to social cues, including threat signals, than are males. Recent theoretical models suggest that developmental changes in brain functioning play important roles in the emergence of such gender differences. METHODS: We used functional magnetic resonance imaging to examine developmental and gender differences in activation of neural structures thought to mediate attention to emotional faces depicting varying degrees of threat. Analyses focused on the orbitofrontal cortex, amygdala, and anterior cingulate cortex during the evaluation of threat conveyed by faces. Healthy adolescents (n = 17; 53% male) and adults (n = 17; 53% male) were scanned while they rated how threatening pictures of neutral and emotional (angry, fearful, or happy) faces appeared. RESULTS: Results indicate significant interactions among age, gender, and face type for activation during explicit threat monitoring. In particular, adult women activated orbitofrontal cortex and amygdala selectively to unambiguous threat (angry) cues, while adult men showed a less discriminating pattern of activation. No gender differences were evident for adolescents, who as a group resembled adult males. CONCLUSIONS: These findings suggest that there are gender differences in patterns of neural responses to emotional faces that are not fully apparent until adulthood.  相似文献   
999.
Strontium ranelate is a new anti‐osteoporotic treatment. On bone biopsies collected from humans receiving long‐term treatment over 5 yr, it has been shown that strontium ranelate has good bone safety and better results than placebo on 3D microarchitecture. Hence, these effects may explain the decreased fracture rate. Introduction: Strontium ranelate's mode of action involving dissociation of bone formation and resorption was shown in preclinical studies and could explain its antifracture efficacy in humans. Materials and Methods: One hundred forty‐one transiliac bone biopsies were obtained from 133 postmenopausal osteoporotic women: 49 biopsies after 1–5 yr of 2 g/d strontium ranelate and 92 biopsies at baseline or after 1–5 yr of placebo. Results and Conclusions: Histomorphometry provided a 2D demonstration of the bone safety of strontium ranelate, with significantly higher mineral apposition rate (MAR) in cancellous bone (+9% versus control, p = 0.019) and borderline higher in cortical bone (+10%, p = 0.056). Osteoblast surfaces were significantly higher (+38% versus control, p = 0.047). 3D analysis of 3‐yr biopsies with treatment (20 biopsies) and placebo (21 biopsies) using μCT showed significant changes in microarchitecture with, in the strontium ranelate group, higher cortical thickness (+18%, p = 0.008) and trabecular number (+14%, p = 0.05), and lower structure model index (?22%, p = 0.01) and trabecular separation (?16%, p = 0.04), with no change in cortical porosity. The changes in 3D microarchitecture may enhance bone biomechanical competence and explain the decreased fracture rate with strontium ranelate.  相似文献   
1000.
The efficacy and tolerability of levocabastine eye drops in vernal conjunctivitis (VC) were evaluated in a double-blind, placebo-controlled trial involving 46 patients over a period of 4 weeks. After 1 week of treatment, therapeutic efficacy was considered to be excellent or good for 70% of the levocabastine-treated patients compared with only 33% of patients in the placebo group (p < 0.009). Levocabastine patients experienced significantly greater relief of their individually severest symptom than placebo-treated patients both after 1 week and at the end of the trial (p < 0.04). The reduction in symptom severity was significantly greater in the levocabastine group than in the control group for photophobia (p < 0.003) after 1 week, and for photophobia (p < 0.008), irritation (p = 0.05) and itchy eyes (p = 0.05) at the end of the trial. The percentage of days on which patients were completely symptom-free was significantly higher in the levocabastine group than in the placebo group (28% versus 4%; p < 0.02). Eight placebo-treated patients withdrew from the trial due to treatment inefficacy compared with only four levocabastine-treated patients (p = 0.013). Two of the three levocabastine, and all five placebo patients who elected to continue on open-label levocabastine had an excellent or good overall response after 1 to 3 weeks of treatment. All reported adverse reactions were mild and their incidence was equal in the two treatment groups. Levocabastine eye drops are effective and well tolerated in the treatment of VC.Abbreviations AUC Area under the curve - VC Vernal conjunctivitis Address for correspondence: J. Coward, Adelphi Communications Limited, Adelphi Mill, Bollington, Macclesfield, Cheshire SK10 5JB, UK Phone: +44 625 575500; Fax: +44 625 575853  相似文献   
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