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排序方式: 共有1333条查询结果,搜索用时 15 毫秒
71.
Margo Schrieken Janne Visser Iris Oosterling Daphne van Steijn Daniëlle Bons Jos Draaisma Rutger-Jan van der Gaag Jan Buitelaar Rogier Donders Nanda Rommelse 《European child & adolescent psychiatry》2013,22(1):35-43
Pre/perinatal risk factors and body growth abnormalities have been studied frequently as early risk markers in autism spectrum disorder (ASD), yet their interrelatedness in ASD has received very little research attention. This is surprising, given that pre/perinatal risk factors can have a substantial impact on growth trajectories in the first years of life. We aimed to determine which pre/perinatal factors were more prevalent in ASD children and if these factors differentially influenced body growth in ASD and control children. A total of 96 ASD and 163 control children matched for gender participated. Data of growth of head size and body length during the first 13 months of life were collected. Data on pre/perinatal risk factors were retrospectively collected through standardized questionnaires. Results indicated that after matching for SES, prematurity/low birth weight and being first born were more prevalent in the ASD versus the control group. In addition, with increasing age children with ASD tended to have a proportionally smaller head circumference compared to their height. However, the effect of prematurity/low birth weight on head growth corrected for height was significantly different in ASD and control children: premature/low birth weight control children showed a disproportionate larger head circumference in relation to height during their first year of life, whereas this effect was absent in premature/low birth weight ASD children. This may suggest that the etiology of abnormal growth is potentially different in ASD and control children: where abnormal growth in control children is related to suboptimal conditions in the uterus, abnormal growth in ASD may be more strongly related to the causal factors that also increase the risk for ASD. However, prospective studies measuring growth and ASD characteristics in both premature/low birth weight and a terme children are necessary to support this conclusion. 相似文献
72.
Heba Nabil Outi Kummu Petri Lehenkari Jaana Rys Juha Risteli Jukka Hakkola Janne Hukkanen 《Basic & clinical pharmacology & toxicology》2022,130(Z1):81-94
Pregnane X receptor (PXR) is a xenobiotic-sensing nuclear receptor that regulates drug metabolism in the liver and intestine. In our clinical trials on healthy volunteers to discover novel metabolic functions of PXR activation, we observed that rifampicin, a well-established ligand for human PXR, 600 mg daily for a week, increased the plasma alkaline phosphatase (ALP) significantly compared with the placebo. Further analysis with lectin affinity electrophoresis revealed that especially the bone form of ALP was elevated. To investigate the mechanism(s) of bone ALP induction, we employed osteoblast lineage differentiated from human primary bone marrow–derived mesenchymal stromal cells. Rifampicin treatment increased ALP activity and mRNA level of bone biomarker genes (ALP, MGP, OPN and OPG). PXR expression was detected in the cells, but the expression was very low compared with the human liver. To further investigate the potential role of PXR in the ALP induction, we treated mice and rats with a rodent PXR ligand pregnenolone 16α-carbonitrile (PCN). However, PCN treatment did not increase plasma ALP activity or bone ALP mRNA expression. In conclusion, rifampicin treatment induces the bone form of ALP in the serum of healthy human volunteers. Further studies are required to establish the mechanism of this novel finding. 相似文献
73.
Mäkinen J Frank C Jyrkkärinne J Gynther J Carlberg C Honkakoski P 《Molecular pharmacology》2002,62(2):366-378
The constitutive androstane receptor (CAR) regulates mouse and human CYP2B genes through binding to the direct repeat-4 (DR4) motifs present in the phenobarbital-responsive enhancer module (PBREM). The preference of PBREM elements for nuclear receptors and the extent of cross-talk between CAR and other nuclear receptors are currently unknown. Our transient transfection and DNA binding experiments indicate that binding to DR4 motifs does not correlate with the activation response and that mouse and human PBREM are efficiently 'insulated' from the effects of other nuclear receptors despite their substantial affinity for DR4 motifs. Certain nuclear receptors that do not bind to DR4 motifs, such as peroxisome proliferator-activated receptor-alpha and farnesoid X receptor, can suppress PBREM function via a coactivator-dependent process that may have relevance in vivo. In competition experiments, mouse PBREM is clearly more selective for CAR than human PBREM. Pregnane X, vitamin D, and thyroid hormone receptors can potentially compete with human CAR on human PBREM. In contrast to the selective nature of PBREM, CYP3A enhancers are highly and comparably responsive to CAR, pregnane X receptor, and vitamin D receptor. In addition, the ligand specificities of human and mouse CAR were defined by mammalian cotransfection and yeast two-hybrid techniques. Our results provide new mechanistic explanations to several previously unresolved aspects of CYP2B and CYP3A gene regulation. 相似文献
74.
Brion F Nilsen BM Eidem JK Goksøyr A Porcher JM 《Environmental toxicology and chemistry / SETAC》2002,21(8):1699-1708
In this study, an enzyme-linked immunosorbent assay (ELISA) was developed to quantify vitellogenin (Vtg) in zebrafish (Danio rerio). Zebrafish Vtg (zf-Vtg) was purified from whole-body homogenates of estradiol-exposed zebrafish, and polyclonal antibodies against zf-Vtg were raised. Using purified zf-Vtg as a standard and anti-zf-Vtg antibodies (DR-264), a competitive ELISA method was set up and validated. The working range of the assay is from 1 to 30 ng/ml (20-80% binding), and the detection limit is 0.4 ng/ml for purified zf-Vtg. In whole-body homogenates samples, the practical detection limit is higher than that for purified Vtg (40 ng/ml) due to matrix effect. The intra- and interassay variations were 4.7% and 14%, respectively, at 50% binding (n = 36). Its usefulness to detect changes in Vtg concentration in other cyprinid fish was also tested. In addition, the assay was used to assess Vtg induction in male zebrafish exposed to 17beta-estradiol (E2). Exposure of male zebrafish to 0.1, 1, 10, and 100 microg/L of E2 for 7 d led to a Vtg induction from the lowest concentration. The results show the suitability of the developed ELISA to quantify Vtg inductions in zebrafish, the cross-reactivity of DR264 antibodies with commonly used cyprinids, and the potential of zf-Vtg induction as a sensitive biochemical endpoint that could be used to detect estrogenic properties of chemical substances. 相似文献
75.
Salminen J Korkama T Strömmer R 《Environmental toxicology and chemistry / SETAC》2002,21(11):2301-2309
Environmental pollution by toxicants is generally believed to lead both to direct toxic effects and indirect effects via altered species interactions in a stressed community. We examined how contamination of a coniferous forest soil floor by lead (from an abandoned shooting range area) may alter trophic interactions and decomposition processes. We constructed laboratory microcosms containing microbial-based food webs with various trophic structures: microbes alone; microbes with microbivorous-detritivorous enchytraeid worms (Cognettia sphagnetorum, a potential keystone species of boreal forest soil); and microbes, worms, and predatory mites (Lysigamasus spp.) together. The direct toxic effect of lead and the effectiveness of the predators in preying upon the worms were studied in separate experiments. Polluted humic soil (acid-extractable lead concentration was 2,720 +/- 349 mg/kg of dry soil [mean +/- standard error]) was toxic to enchytraeids, and predators effectively reduced worm populations. Positive density-dependent effects of worms on microbes and a trophic cascade from predatory mites to microbes, observed in the unpolluted humus, were not observed in the polluted humus, indicating pollution-induced interaction modification among organisms. Concomitantly, lead pollution altered the process of nutrient mineralization in the humic soil. However, causality and relative importance of direct toxicity and indirect effects of lead on the dynamics of the decomposer food web could not be pointed out. Examination of our results indicates that traditional food web models are incapable of predicting mechanisms that alter dynamics of pollution-stressed belowground food webs. 相似文献
76.
We have recently demonstrated a moderate vaccination response rate of 43% against Haemophilus influenzae type b (Hib) conjugate vaccine among adult and elderly patients with chronic lymphocytic leukaemia (CLL). We now investigated demographic and immunological factors predicting the favourable response and protective antibody concentrations for Hib conjugate vaccine in CLL. Lower age was associated with protective pre- and post-vaccination antibody concentrations. High IgG1 and IgA concentrations were also associated with the protective efficacy. High IgM, in turn, was the best predictor of a significant vaccination response. Again, lower age seemed to be involved in this outcome. Judging from these findings, it would seem beneficial to vaccinate all CLL patients with conjugate vaccines at the presentation of the disease. Investigations of a new pneumococcal conjugate vaccine in CLL are warranted. 相似文献
77.
Circulating tumor cells in the peripheral blood and bone marrow of patients with ovarian carcinoma do not predict prognosis 总被引:5,自引:0,他引:5
BACKGROUND: Ovarian carcinoma is apparently restricted for a long time to the peritoneal cavity. However, about 50% of patients with a surgically documented complete intraabdominal response experience later recurrence. Occult hematogenous micrometastases are common to most epithelial malignancies and have recently been found in 30% of bone marrow samples of ovarian carcinoma patients, as examined by immunocytochemistry. Moreover, these findings were associated with poor progression-free and overall survival. The aim of the current study was to evaluate the possible prognostic significance of tumor cells detected in the peripheral blood and bone marrow of ovarian carcinoma patients by an immunomagnetic method. METHODS: In a total of 90 patients with histologically proven epithelial ovarian carcinoma, blood and (in 73 cases) bone marrow samples were taken. Tumor cells were identified by a microbead coated with the antibody MOC-31, which recognizes an epitope regularly expressed on ovarian carcinoma cells. RESULTS: The authors detected carcinoma cells in the bone marrow in 21% of ovarian carcinoma patients, and in the peripheral blood in 12% of patients. Mean overall survival was 25 and 28 months for patients with or without circulating tumor cells, respectively. CONCLUSIONS: Ovarian carcinoma cells seem to reach peripheral circulation more frequently than expected. However, in contrast to an earlier report, detection of tumor cells in the bone marrow and/or blood was not associated with poor prognosis in ovarian carcinoma patients. This discrepancy remains unexplained, but characterization of circulating ovarian carcinoma cells for their malignant and metastatic capacity is clearly warranted. 相似文献
78.
Comparison of two procedures for meniscal cysts. A report of 35 patients with a mean follow-up of 33 months 总被引:1,自引:0,他引:1
BACKGROUND: The cause, pathogenesis, and appropriate treatment of meniscal cysts remain controversial. PURPOSE: We wanted to evaluate the results of treatment of meniscal cysts with two different operative procedures. STUDY DESIGN: Prospective cohort study. METHODS: Two different operative procedures were compared. Sixteen patients (group 1) had an open excision of the cyst performed in addition to arthroscopic examination of the knee. Nineteen patients (group 2) were treated entirely arthroscopically. The postoperative treatment course was the same for both groups. The mean length of follow-up was 33 months. RESULTS: The results were excellent or good in 86% of the patients (30 of 35) and were equally good for both procedures. Patients with degenerative changes of the knee joint seemed to have a less favorable outcome. CONCLUSIONS: Good or excellent results can be expected from either open or arthroscopic treatment of meniscal cysts. 相似文献
79.
80.
Janne Kaern Claes Trop Kolbein Sundfoer Gunnar B. Kristensen 《Gynecologic oncology》1996,60(3):387-392
Objective: To evaluate the response rate and corrected survival in patients with recurrent cervical carcinoma (RCC) treated with 100 mg/m2cisplatin (CDDP) iv on Day 1 and 1000 mg/m25-fluorouracil (5-FU) iv on Days 1 to 5. Methods: A phase II study of CDDP/5-FU in RCC was initiated in 1986. Up to December 1991, a total of 72 patients were enrolled. Of these, 65 were evaluable for response. Results: The overall response rate was 49%. For 9 patients with complete remission, the median duration of response was 16 months, range 6 to 79+. The corresponding figures for 26 patients with partial remission were 10 months, range 3 to 80 months. By multivariate analysis, FIGO stage, disease-free interval, WHO performance status, and number of lesions at recurrence were independent prognostic variables. Twenty-two percent of the patients survived for more than 2 years and 9% for more than 5 years. Toxicity was tolerable. Leucopenia, ototoxicity, and neurotoxicity were the main problems. Conclusion: A high response rate (49%) was observed with CDDP/5-FU treatment in patients with RCC with 9% of the patients surviving for more than 5 years. 相似文献