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排序方式: 共有973条查询结果,搜索用时 15 毫秒
91.
92.
Jaana I. Halonen Jussi Vahtera Stephen Stansfeld Tarja Yli-Tuomi Paula Salo Jaana Pentti Mika Kivim?ki Timo Lanki 《Environmental health perspectives》2012,120(10):1391-1396
Background: Associations between traffic noise and sleep problems have been detected in experimental studies, but population-level evidence is scarce.Objectives: We studied the relationship between the levels of nighttime traffic noise and sleep disturbances and identified vulnerable population groups.Methods: Noise levels of nighttime–outdoor traffic were modeled based on the traffic intensities in the cities of Helsinki and Vantaa, Finland. In these cities, 7,019 public sector employees (81% women) responded to postal surveys on sleep and health. We linked modeled outdoor noise levels to the residences of the employees who responded to the postal survey. We used logistic regression models to estimate associations of noise levels with subjectively assessed duration of sleep and symptoms of insomnia (i.e., difficulties falling asleep, waking up frequently during the night, waking up too early in the morning, nonrestorative sleep). We also used stratified models to investigate the possibility of vulnerable subgroups.Results: For the total study population, exposure to levels of nighttime–outside (Lnight, outside) traffic noise > 55 dB was associated with any insomnia symptom ≥ 2 nights per week [odds ratio (OR) = 1.32; 95% confidence interval (CI): 1.05, 1.65]. Among participants with higher trait anxiety scores, which we hypothesized were a proxy for noise sensitivity, the ORs for any insomnia symptom at exposures to Lnight, outside traffic noises 50.1–55 dB and > 55 dB versus ≤ 45 dB were 1.34 (95% CI: 1.00, 1.80) and 1.61 (95% CI: 1.07, 2.42), respectively.Conclusions: Nighttime traffic noise levels > 50 dB Lnight, outside was associated with insomnia symptoms among persons with higher scores for trait anxiety. For the total study population, Lnight, outside > 55 dB was positively associated with any symptoms. 相似文献
93.
The development of resistance to current antifungal therapeutics drives the search for effective new agents. The fact that some acetophenone-derived Mannich bases had shown antifungal activities in our previous studies led us to design and synthesize acetophenone-derived bis Mannich bases, B1-B5, bis(beta-aroylethyl)methylamine hydrochlorides, to evaluate their antifungal activity. These bis Mannich bases were then converted to the corresponding piperidinols, C1-C5, which are structural isomers of bis derivatives, 3-aroyl-4-aryl-1-methyl-4-piperidinol hydrochlorides, to see alterations in biological activity. A stability study of B1 and Cl was also carried out to estimate whether they alkylate the thiols. All compounds studied have shown antifungal activity, especially against dermatophytes (Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans, and Microsporum canis), in the concentration range studied (2-128 microng/ml). The activity was especially apparent against T. tonsurans. All compounds had at least equal antifungal activity compared with the reference compound amphotericin-B against T. tonsurans. Bis Mannich bases were generally found to be more potent compounds than their structural isomer piperidinols. The results of our stability studies suggest that thiol alkylation may contribute to the antifungal activity of the Mannich bases synthesized. Even though all compounds showed antifungal activity against dermatophytes, bis Mannich bases B1, B2, B4, and B5 appear to have potential for developing novel antifungal agents against dermatophytes. 相似文献
94.
Kaasinen V Någren K Järvenpää T Roivainen A Yu M Oikonen V Kurki T Rinne JO 《Journal of clinical psychopharmacology》2002,22(6):615-620
Donepezil and rivastigmine are acetylcholinesterase (AChE) inhibitors used to improve cholinergic neurotransmission and cognitive function in Alzheimer's disease (AD). This study examined direct effects of these drugs on AChE activity in the frontal, temporal, and parietal cortices in AD. Six AD patients were scanned with positron emission tomography before and after 3 months of treatment with donepezil (10 mg/day), and five AD patients were scanned before and after 3 to 5 months of treatment with rivastigmine (9 mg/day). Healthy unmedicated controls were imaged twice to evaluate the reproducibility of the method. A specific AChE tracer, [methyl-11C]N-methyl-piperidyl-4-acetate, and a 3D positron emission tomography system with MRI coregistration were used for imaging. Treatment with donepezil reduced the AChE activity (k3 values) in the AD brain by 39% in the frontal (p < 0.001, Bonferroni corrected), 29% in the temporal (p = 0.02, corrected) and 28% in the parietal cortex (p = 0.05, corrected). The corresponding levels of inhibition for rivastigmine were 37% (p = 0.003, corrected), 28% (p = 0.03, uncorrected) and 28% (p = 0.05, corrected). When the treatment groups were combined, the level of AChE inhibition was significantly greater in the frontal cortex compared to the temporal cortex (p = 0.03, corrected). The test-retest analysis with healthy subjects indicated good reproducibility for the method, with a nonsignificant 0% to 7% intrasubject variability between scans. The present study provides first evidence for the effect of rivastigmine on cortical AChE activity. Our results indicate that the pooled effects of donepezil and rivastigmine on brain AChE are greater in the frontal cortex compared to the temporal cortex in AD. This regional difference is probably related to the prominent temporoparietal reduction of AChE in AD. We hypothesize that the clinical improvement in behavioral and attentional symptoms of AD due to AChE inhibitors is associated with the frontal AChE inhibition. 相似文献
95.
Christina M Krause Petra-Ann Boman Lauri Sillanm?ki Tarja Varho Irma E Holopainen 《Seizure》2008,17(1):1-10
PURPOSE: Children with epilepsy are in risk for cognitive impairment, but reliable methods, other than neuropsychological testing, to verify such a decline are few. The purpose of this study was to assess the effect of infrequent seizures on cognitive skills in children with non-symptomatic focal epilepsy taking antiepileptic medication but still having infrequent seizures. METHODS: EEG (electroencephalogram) brain electric oscillatory responses of the 4-6Hz, 6-8Hz, 8-10Hz and 10-12Hz EEG frequency bands were studied. These responses, assessed by means of the event-related desynchronization (ERD) and synchronization (ERS) method, were recorded in 6 children with epilepsy (mean age 11.3 years) and in 11 control children (mean age 12 years) while they performed an auditory memory task. All subjects also underwent a comprehensive neuropsychological test battery. RESULTS: The differences in the 4-6Hz ERD/ERS responses between encoding and recognition were smaller in the children with epilepsy as compared to those of the control children. In the 6-8Hz frequency band, the responses of the two groups dissociated most notably in the frontal electrodes. No statistically significant differences in the alpha frequency range (8-12Hz) were observed between the groups. CONCLUSIONS: Significant alterations in the lower EEG frequency (4-8Hz) ERD/ERS responses in children with epilepsy during auditory memory processing, as compared to age-matched, healthy children may suggest that seizures affect memory and underlying brain processes, indexed also by poorer performance particularly in neuropsychological subtests related to language functions. 相似文献
96.
Comparison of an immortalized human corneal epithelial cell line and rabbit corneal epithelial cell culture in cytotoxicity testing. 总被引:3,自引:0,他引:3
Anne Huhtala Marika Mannerstr?m P?ivi Alajuuma Sami Nurmi Tarja Toimela Hanna T?hti Lotta Salminen Hannu Uusitalo 《Journal of ocular pharmacology and therapeutics》2002,18(2):163-175
The cytotoxicity of benzalkonium chloride (BAC) and disodium edetate (EDTA) was evaluated in vitro in rabbit corneal epithelial primary cells and in the immortalized human corneal epithelial cell line SV40. Cell injury was assessed by lactate dehydrogenase (LDH) leakage and by reduction of the tetrazolium salt WST-1 to formazan by mitochondrial metabolic activity. Cell cultures were exposed to test compounds both in serum-free and in serum-containing medium. Although WST-1 and LDH tests measured different physiological endpoints, they yielded comparable results. However, the LDH test seemed less reliable due to great variation. The use of serum was found to result in lower toxicity of the compounds in both tests. The rabbit primary cell culture and the human corneal cell line were quite similar in their responses to BAC and EDTA. The human cell line is a promising in vitro alternative in oculotoxicity testing. 相似文献
97.
Leptin is best known as a regulator of energy homeostasis, but it also interacts with sleep and breathing. Leptin secretion increases at night and decreases during the day. The circadian secretory profile of leptin is determined both by the hypothalamic circadian pacemaker and sleep-wake cycle. Leptin is also a powerful respiratory stimulant. Serum leptin levels are higher in obstructive sleep apnoea syndrome but lower during extended sleep deprivation in healthy subjects or in narcolepsy. Abnormalities in serum leptin concentrations have recently been linked with deleterious effects on weight control, cardiovascular health and glucose regulation. Since sleep curtailment and sleep-disordered breathing are epidemics of the modern society, better understanding of leptin pathophysiology could open new perspectives to pathophysiology of major public diseases, including obesity and metabolic syndrome. 相似文献
98.
Pölkki T Pietilä AM Vehviläinen-Julkunen K 《International journal of nursing studies》2003,40(1):33-44
The purpose of this study was to describe children's (aged 8-12 yr) experiences with postsurgical pain relieving methods, and their suggestions to nurses and parents concerning the implementation of pain relief measures in the hospital. The data were collected by interviewing children (N = 52) who were inpatients on a pediatric surgical ward in the university hospital of Finland. Content analysis was used to analyze the data. The children rated the intensity of pain on a visual analogue scale. The results indicated that all of the children used at least one self-initiated pain relieving method (e.g. distraction, resting/sleeping), in addition to receiving assistance in pain relief from nurses (e.g. giving pain killers, helping with daily activities) and parents (e.g. distraction, presence). The children also provided suggestions, especially as it relates to nurses (e.g. creating a more comfortable environment), regarding the implementation of effective surgical pain relief. However, some cognitive-behavioral and physical methods were identified that should be implemented more frequently in clinical practice. Furthermore, most children reported their worst pain to be severe or moderate, which indicates that pain management in hospitalized children should be more aggressive. 相似文献
99.
100.
This study describes moral judgment among first- and last-year nursing students in Finland and examines the effects of ethics teaching on the development of moral judgment. The data for this quantitative cross-sectional study were collected using the Defining Issues Test (DIT), which is based on Kohlberg's theory of moral reasoning stages. The questionnaires were sent to four polytechnics, which offer nursing education in southern Finland. A total of 52 first-year students and 54 last-year students participated. The results showed that students who had had to deal with ethical dilemmas in their practical training had higher moral judgment than students who did not. Last-year students had higher moral judgment than first-year students. Last-year students resorted to principle-based thinking more often than first-year students in resolving DIT dilemmas. The differences between the two groups were statistically significant. The results indicate that nursing education may has an effect upon students' moral judgment. 相似文献