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排序方式: 共有580条查询结果,搜索用时 15 毫秒
491.
The effect of particles from road traffic and wood smoke on the innate immune response in the lung was studied in a lung challenge model with the intracellular bacterium Listeria monocytogenes. Female Balb/cA mice were instilled intratracheally with wood smoke particles, particles from road traffic collected during winter (studded tires used; St+), and during autumn (no studded tires; St?), or diesel exhaust particles (DEP). Simultaneously with, and 1 or 7 days after particle instillation, 105 bacteria were inoculated intratracheally. Bacterial numbers in the lungs and spleen 1 day after Listeria challenge were determined, as an indicator of cellular activation. In separate experiments, bronchoalveolar lavage (BAL) fluid was collected 4?h and 24?h after particle instillation. All particles tested reduced the numbers of bacteria in the lung 24?h after bacterial inoculation. When particles were given simultaneously with Listeria, the reduction was greatest for DEP, followed by St+ and St?, and least for wood smoke particles. Particle effects were no longer apparent after 7 days. Neutrophil numbers in BAL fluid were increased for all particle exposed groups. St+ and St? induced the highest levels of IL-1β, MIP-2, MCP-1, and TNF-α, followed by DEP, which induced no TNF-α. In contrast, wood smoke particles only increased lactate dehydrogenase (LDH) activity, indicating a cytotoxic effect of these particles. In conclusion, all particles tested activated the innate immune system as determined with Listeria. However, differences in kinetics of anti-Listeria activity and levels of proinflammatory mediators point to cellular activation by different mechanisms. 相似文献
492.
Torgersen L Ystrom E Haugen M Meltzer HM Von Holle A Berg CK Reichborn-Kjennerud T Bulik CM 《Maternal & child nutrition》2010,6(3):243-252
The purpose of this study was to compare the prevalence of breastfeeding in women with anorexia nervosa, bulimia nervosa, binge eating disorder and eating disorders not otherwise specified – purging subtype, with mothers with no eating disorders during the first 6 months after birth. The study is based on the Norwegian Mother and Child Cohort Study conducted at the Norwegian Institute of Public Health. Questionnaire‐based information on eating disorder diagnoses and breastfeeding in 39 355 women was used to estimate the risk of cessation of breastfeeding with Cox proportional hazards regression. Almost all women (98%) initially breastfeed their infants, with no statistically significant difference between the eating disorders subgroups and women with no eating disorders. However, the risk of early cessation before 6 months post‐partum increased for all subgroups of mothers with eating disorders, compared with mothers with no eating disorders. After adjusting for maternal body mass index, age, education, birthweight and pre‐term birth, only mothers with anorexia nervosa [hazard ratios (HR), 2.35; 95% confidence interval (CI) 1.22–4.53] and eating disorder not otherwise specified‐purging subtype (HR, 1.95; 95% CI 1.08–3.53) had increased risk for cessation of breastfeeding There were no differences in the risk of cessation of exclusive breastfeeding. These results show that some eating disorders may influence mothers' early feeding practices and indicate that additional support may be necessary to assist women with anorexia nervosa in maintaining breastfeeding. 相似文献
493.
The 5-HT4 receptor modulates activity of serotonergic neurons and is a new potential target for antidepressant treatment. This microdialysis study evaluated the effect of the 5-HT4 receptor agonist, RS67333, on extracellular serotonin (5-hydroxytryptamine, 5-HT) and 5-HIAA levels in rat ventral hippocampus during chloral hydrate anaesthesia, and explored the ability of RS67333 to augment the effect of the selective serotonin reuptake inhibitor paroxetine. The effect of RS67333 was examined after acute and subchronic (3 days) administration. Acute RS67333 (1.5 mg/kg i.v.) had no effect on extracellular 5-HT or 5-HIAA levels, while acute paroxetine (0.5 mg/kg i.v.) increased 5-HT levels by 299 ± 16% and decreased 5-HIAA levels by 25 ± 4%. Administration of RS67333 80 min after paroxetine caused an additional transient increase in 5-HT levels (to 398 ± 52% of baseline). Subchronic RS67333 administration (1.5 mg/kg i.p.) increased basal 5-HT levels by 73 ± 15% and decreased 5-HIAA levels by 27 ± 13%. In conclusion, the 5-HT4 receptor agonist RS67333 augmented the acute effect of paroxetine on extracellular 5-HT levels in the ventral hippocampus, and after 3 days increased basal hippocampal 5-HT levels. 相似文献
494.
Solvor Berntsen Stølevik Unni Cecilie Nygaard Berit Granum 《Food and chemical toxicology》2011,49(8):1843-1848
The birth cohort BraMat (n = 205; a sub-cohort of the Norwegian Mother and Child Cohort Study (MoBa) conducted by the Norwegian Institute of Public Health) was established to study whether prenatal exposure to toxicants from the maternal diet affects immunological health outcomes in children. We here report on the environmental pollutants polychlorinated biphenyls (PCBs) and dioxins, as well as acrylamide generated in food during heat treatment. The frequency of common infections, eczema or itchiness, and periods of more than 10 days of dry cough, chest tightness or wheeze (called wheeze) in the children during the first year of life was assessed by questionnaire data (n = 195). Prenatal dietary exposure to the toxicants was estimated using a validated food frequency questionnaire from MoBa. Prenatal exposure to PCBs and dioxins was found to be associated with increased risk of wheeze and exanthema subitum, and also with increased frequency of upper respiratory tract infections. We found no associations between prenatal exposure to acrylamide and the health outcomes investigated. Our results suggest that prenatal dietary exposure to dioxins and PCBs may increase the risk of wheeze and infectious diseases during the first year of life. 相似文献
495.
Frank J. E. Vajda Alison A. Hitchcock Janet Graham Terence J. O’Brien Cecilie M. Lander Mervyn J. Eadie 《Epilepsia》2010,51(5):805-810
Purpose: To compare the risks of fetal malformation during pregnancy associated with antiepileptic drug (AED) polytherapy and monotherapy. Methods: Statistical analysis of malformation rate and antiepileptic drug exposure data from the Australian Register of Antiepileptic Drugs in Pregnancy, and from the literature. Results: The calculated relative risk (RR) value for AED polytherapy compared with monotherapy was below 1.0 in only 3 of 14 literature publications. In the register, at 1 year postnatally there were fetal malformations in 5.32% of 282 AED polytherapy pregnancies, and in 7.84% of 791 AED monotherapy pregnancies, an RR of 0.68 [95% confidence interval (CI) 0.39–1.17). For pregnancies exposed to valproate, the RR of fetal malformation (0.39, 95% CI 0.20–0.89) was lower in polytherapy (7.26%) than in monotherapy (17.9%); the difference did not depend on valproate dosage. The RR values for fetal malformation were not significantly different for AED polytherapy and monotherapy when valproate was not involved. Logistic regression suggested that coadministration of lamotrigine may have reduced the malformation risk from valproate. Discussion: The fetal hazard of AED polytherapy relative to monotherapy may depend more on the degree of exposure to valproate than on the fact of polytherapy per se. Coadministration with lamotrigine may lower the fetal risk of valproate therapy. 相似文献
496.
497.
Jennings KA Licht CL Bruce A Lesch KP Knudsen GM Sharp T 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2012,15(8):1099-1107
Genetic variation in 5-HT transporter (5-HTT) expression is a key risk factor for psychiatric disorder and has been linked to changes in the expression of certain 5-HT receptor subtypes. This study investigated the effect of variation in 5-HTT expression on 5-HT? receptor levels in both 5-HTT knockout (KO) and overexpressing (OE) mice using autoradiography with the selective 5-HT? receptor radioligand, [3H]SB207145. Compared to wild-type (5-HTT?/?) controls, homozygous 5-HTT KO mice (5-HTT?/?) had reduced 5-HT? receptor binding site density in all brain regions examined (35-65% of 5-HTT?/?). In contrast, the density of 5-HT? receptor binding sites was not significantly different between heterozygous 5-HTT KO mice (5-HTT?/?) and 5-HTT?/? mice. The 5-HT synthesis inhibitor p-chlorophenylalanine (250 mg/kg twice daily for 3 d) abolished the difference in 5-HT? binding between 5-HTT?/? and 5-HTT?/? mice in all brain regions. Compared to wild-type (WT) littermate controls, 5-HTT OE mice had increased 5-HT? binding density across all brain regions, except amygdala (118-164% of WT) and this difference between genotypes was reduced by the 5-HTT inhibitor, fluoxetine (20 mg/kg twice daily, 3 d). Together, these findings suggest that variation in 5-HTT expression causes adaptive changes in 5-HT? receptor levels which are directly linked to alterations in 5-HT availability. 相似文献
498.
499.
Tropé A Sjøborg KD Nygård M Røysland K Campbell S Alfsen GC Jonassen CM 《Journal of clinical microbiology》2012,50(6):1927-1935
We carried out a prospective study comparing the performance of human papillomavirus (HPV) E6/E7 mRNA (PreTect HPV-Proofer; NorChip, Klokkarstua, Norway) and DNA (Amplicor HPV test; Roche Diagnostics, Basel, Switzerland) triage testing of women 6 to 12 months after atypical-squamous-cells-of-undetermined-significance (ASCUS) or low-grade-squamous-intraepithelial-lesion (LSIL) cytology in organized screening to predict high-grade cervical intraepithelial neoplasia of grade 2 or worse (CIN2+) between screening rounds. Between January 2005 and April 2008, 692 study women with screening-detected ASCUS/LSIL cytology 6 to 12 months earlier returned for HPV mRNA and DNA testing and repeat cytology. The median follow-up time was 3 years, using existing health care facilities. Follow-up test results were available for 625 women. Of the 145 CIN2+ cases detected during the study period, 95 (65.5%) were HPV mRNA positive 6 to 12 months after screening-detected ASCUS/LSIL, 44 (30.4%) were HPV mRNA negative, and 6 (4.1%) were invalid. The corresponding HPV DNA results were 139 (95.9%), 5 (3.4%), and 1 (0.7%), respectively. The cumulative incidences of CIN2+ 3 years after a negative HPV mRNA and DNA test were 10.3% (95% confidence interval [CI], 7.2 to 13.3%) and 1.8% (95% CI, 0.0 to 3.6%), respectively. The cumulative incidences of CIN2+ 3 years after positive HPV mRNA and DNA tests were 52.8% (95% CI, 40.1 to 60.1%) and 41.3% (95% CI, 35.5 to 46.6%), respectively. In conclusion, both positive HPV mRNA and DNA test results have a high enough long-term prediction of CIN2+ risk to consider referral to colposcopy as good practice when performed in delayed triage of women with ASCUS/LSIL cytology. In addition, the low CIN2+ risk among women with a negative Amplicor HPV test in our study confirms its safe use in a clinical setting. 相似文献
500.
Effect of DISC1 SNPs on brain structure in healthy controls and patients with a history of psychosis
AK K?hler LM Rimol AA Brown S Djurovic CB Hartberg I Melle AM Dale OA Andreassen I Agartz 《American journal of medical genetics. Part B, Neuropsychiatric genetics》2012,(6):722-730
Disrupted-in-Schizophrenia-1 (DISC1) has been suggested as a susceptibility locus for a broad spectrum of psychiatric disorders. Risk variants have been associated with brain structural changes, which overlap alterations reported in schizophrenia and bipolar disorder patients. We used genome-wide genotyping data for a Norwegian sample of healthy controls (n?=?171) and patients with a history of psychosis (n?=?184), to investigate 61 SNPs in the DISC1 region for putative association with structural magnetic resonance imaging (sMRI) measures (hippocampal volume; mean cortical thickness; and total surface area, as well as cortical thickness and area divided into four lobar measures). SNP rs821589 was associated with mean temporal and total brain cortical thickness in controls (P(adjusted) =?0.009 and 0.02, respectively), but not in patients. SNPs rs11122319 and rs1417584 were associated with mean temporal cortical thickness in patients (P(adjusted) =?0.04 and 0.03, respectively), but not in controls, and both SNPs have previously been highly associated with DISC1 gene expression. There were significant genotype?× case-control interactions. There was no significant association between SNPs and cortical area or hippocampal volume in controls, or with any of the structural measures in cases, after correction for multiple comparisons. In conclusion, DISC1 SNPs might impact brain structural variation, possibly differently in psychosis patients versus controls, but independent replication will be needed to confirm our findings. ? 2012 Wiley Periodicals, Inc. 相似文献