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排序方式: 共有1246条查询结果,搜索用时 46 毫秒
101.
Wessel W. Fuijkschot Hjalmar J. de Graaff Ekatarina Berishvili Zurab Kakabadze Koba Kupreishvili Elisa Meinster Maaike Houtman Amber van Broekhoven Casper G. Schalkwijk Alexander B. A. Vonk Paul A. J. Krijnen Yvo M. Smulders Hans W. N. Niessen 《European journal of clinical investigation》2016,46(4):334-341
102.
Nielsen FK Hansen CH Fey JA Hansen M Jacobsen NW Halling-S?rensen B Bj?rklund E Styrishave B 《Toxicology in vitro》2012,26(2):343-350
The effects of three model endocrine disruptors, prochloraz, ketoconazole and genistein on steroidogenesis were tested in the adrenocortical H295R cell line to demonstrate that a broader mechanistic understanding can be achieved in one assay by applying chemical analysis to the H295R assay. Seven key steroid hormones (pregnenolone, progesterone, dehydroepiandrosterone, androstenedione, testosterone, estrone and 17β-estradiol) were analyzed using a novel and thoroughly validated GC-MS/MS method. In addition to the simultaneous quantification of 7 steroid hormones, the present method also negates the potential problems of cross-reactivity that can be encountered in some immunoassays. Although all 3 test compounds decrease the concentrations of the main sex steroids, the chemicals exerted different effects upstream in the pathway. Exposure to prochloraz resulted in increased hormone levels upstream of steroid 17 alpha-hydroxylase/17,20 lyase (P450c17) and decreases downstream. Ketoconazole inhibited the entire pathway, while exposure to genistein resulted in increased hormone levels upstream of 3-β-hydroxysteroid dehydrogenase (3β-HSD) and decreases downstream. The results demonstrate that chemical analysis combined with the H295R cell assay is an useful tool for studying the mechanisms by which endocrine disruptors interfere with the steroidogenic pathway. 相似文献
103.
104.
Hedy Vkony Kerstin Rser Thomas Lning Bauke Ylstra Gerrit A. Meijer Wessel N. van Wieringen Mark A. van de Wiel Beatriz Carvalho Klaas Kok C. Ren Leemans Isac van der Waal Elisabeth Bloemena 《Genes, chromosomes & cancer》2009,48(2):202-212
Salivary gland myoepithelial tumors are relatively uncommon tumors with an unpredictable clinical course. More knowledge about their genetic profiles is necessary to identify novel predictors of disease. In this study, we subjected 27 primary tumors (15 myoepitheliomas and 12 myoepithelial carcinomas) to genome‐wide microarray‐based comparative genomic hybridization (array CGH). We set out to delineate known chromosomal aberrations in more detail and to unravel chromosomal differences between benign myoepitheliomas and myoepithelial carcinomas. Patterns of DNA copy number aberrations were analyzed by unsupervised hierarchical cluster analysis. Both benign and malignant tumors revealed a limited amount of chromosomal alterations (median of 5 and 7.5, respectively). In both tumor groups, high frequency gains (≥20%) were found mainly at loci of growth factors and growth factor receptors (e.g., PDGF, FGF(R)s, and EGFR). In myoepitheliomas, high frequency losses (≥20%) were detected at regions of proto‐cadherins. Cluster analysis of the array CGH data identified three clusters. Differential copy numbers on chromosome arm 8q and chromosome 17 set the clusters apart. Cluster 1 contained a mixture of the two phenotypes (n = 10), cluster 2 included mostly benign tumors (n = 10), and cluster 3 only contained carcinomas (n = 7). Supervised analysis between malignant and benign tumors revealed a 36 Mbp‐region at 8q being more frequently gained in malignant tumors (P = 0.007, FDR = 0.05). This is the first study investigating genomic differences between benign and malignant myoepithelial tumors of the salivary glands at a genomic level. Both unsupervised and supervised analysis of the genomic profiles revealed chromosome arm 8q to be involved in the malignant phenotype of salivary gland myoepitheliomas. © 2008 Wiley‐Liss, Inc. 相似文献
105.
PD Dr. habil. T. Erler U. Beyer B. Hoch G. Jorch K. Klementz A. Kramer E. Paditz C.F. Poets L. Wessel A. Wiater 《Somnologie - Schlafforschung und Schlafmedizin》2009,13(3):182-188
Comprehensive ambulatory care structures, more efficient technology as well as the parents’ willingness to take care of chronically ill children at home, requires higher standards of home monitoring systems. Some difficulties are caused by medical indications, the period of the application and the type of apparatus used in each case. Based on formally assessed evidence (evidence level), the presented guidelines for“Home monitoring of children and adolescents” were developed by reviewing the scientific literature and approved by a consensus procedure (S2). In a concluding assessment, recommendations are given outlining which application of monitoring disease patterns appears appropriate. Statements will be given on which parameters should be monitored, the time of monitoring, the technical requirements of the apparatus and the attendant circumstances of home monitoring. 相似文献
106.
Angiogenic factors like placental growth factor and its antiangiogenic antagonist soluble fms-like tyrosine kinase 1 (sFlt1) are closely related to the pathogenesis of preeclampsia and intrauterine growth restriction. Because it is known that altered maternal sFlt1 and placental growth factor levels are detectable weeks before the onset of these pregnancy complications, it was the aim of the study to investigate the predictive value of these markers in high-risk second trimester pregnancies characterized by abnormal uterine perfusion. This prospective study includes 63 second trimester pregnant women with abnormal uterine perfusion. Twenty five of them developed a later complication (12 with preeclampsia, 11 with intrauterine growth restriction, and 2 with intrauterine death), whereas 38 had a normal course of pregnancy. Pregnancies with adverse pregnancy outcome showed in the second trimester significantly higher sFlt1 (1403.6+/-555 versus 451.8+/-42 pg/mL; P<0.05) and lower placental growth factor (139.6+/-24 versus 184.1+/-21 pg/mL) levels compared with those with normal outcome. These alterations were more pronounced in pregnancies with subsequent preeclampsia compared with intrauterine growth restriction and early onset diseases (delivery <34 weeks) compared with late-onset diseases. The combination of Doppler and sFlt1 increases the sensitivity of Doppler alone for iatrogenic preterm delivery from 64% up to 79% and the specificity from 63% up to 80%. Using both factors, sFlt1 and placental growth factor, early onset preeclampsia can be predicted with 83% sensitivity and 95% specificity. We conclude that the concurrent measurement of uterine perfusion and angiogenic factors allows an efficient prediction of early onset pregnancy complications, particularly preeclampsia. 相似文献
107.
Wessel J Moratorio G Rao F Mahata M Zhang L Greene W Rana BK Kennedy BP Khandrika S Huang P Lillie EO Shih PA Smith DW Wen G Hamilton BA Ziegler MG Witztum JL Schork NJ Schmid-Schönbein GW O'Connor DT 《Journal of hypertension》2007,25(2):329-343
BACKGROUND: C-reactive protein (CRP) both reflects and participates in inflammation, and its circulating concentration marks cardiovascular risk. Here we sought to understand the role of heredity in determining CRP secretion. METHODS: CRP, as well as multiple facets of the metabolic syndrome, were measured in a series of 229 twins, both monozygotic (MZ) and dizygotic (DZ), to estimate trait heritability (h2). Single nucleotide polymorphism (SNP) genotyping was done at adrenergic pathway loci. Haplotypes were inferred from genotypes by likelihood methods. Association of CRP with hypertension and the metabolic syndrome was studied in a larger series of 732 individuals, including 79 with hypertension. RESULTS: MZ and DZ twin variance components indicated substantial h2 for CRP, at approximately 56 +/- 7% (P < 0.001). CRP was significantly associated (P < 0.05) with multiple features of the metabolic syndrome in twins, including body mass index (BMI), blood pressure (BP), leptin and lipids. In established hypertension, elevated CRP was associated with increased BP, BMI, insulin, HOMA (index of insulin resistance), leptin, triglycerides and norepinephrine. Twin correlations indicated pleiotropy (shared genetic determination) for CRP with BMI (P = 0.0002), leptin (P < 0.001), triglycerides (P = 0.002) and systolic blood pressure (SBP) (P = 0.042). Approximately 9800 genotypes (43 genetic variants at 17 loci) were scored within catecholaminergic pathways: biosynthetic, receptor and signal transduction. Plasma CRP concentration in twins was predicted by polymorphisms at three loci in physiological series within the catecholamine biosynthetic/beta-adrenergic pathway: TH (tyrosine hydroxylase), ADRB1 (beta1-adrenergic receptor) and ADRB2 (beta2-adrenergic receptor). In the TH promoter, common allelic variation accounted for up to approximately 6.6% of CRP inter-individual variance. At ADRB1, variation at Gly389Arg predicted approximately 2.8% of CRP, while ADRB2 promoter variants T-47C and T-20C also contributed. Particular haplotypes and diplotypes at TH and ADRB1 also predicted CRP, though typically no better than single SNPs alone. Epistasis (gene-by-gene interaction) was demonstrated for particular combinations of TH and ADRB2 alleles, consistent with their actions in a pathway in series. In an illustration of pleiotropy, not only CRP but also plasma triglycerides were predicted by polymorphisms at TH (P = 0.0053) and ADRB2 (P = 0.027). CONCLUSIONS: CRP secretion is substantially heritable in humans, demonstrating pleiotropy (shared genetic determination) with other features of the metabolic syndrome, such as BMI, triglycerides or BP. Multiple, common genetic variants in the catecholaminergic/beta-adrenergic pathway contribute to CRP, and these variants (especially at TH and ADRB2) seem to interact (epistasis) to influence the trait. The results uncover novel pathophysiological links between the adrenergic system and inflammation, and suggest new strategies to probe the role and actions of inflammation within this setting. 相似文献
108.
Schlote A Poppendick U Möller C Wessel K Wunderlich M Wallesch CW 《Die Rehabilitation》2008,47(3):136-144
BACKGROUND: The literature predicts a considerable demand of support and aid for stroke patients and their caregivers. It is not known to what extent existing resources are used by these groups. PURPOSE: The present study aimed at a survey of knowledge of and acquaintance with institutions and organizations offering support after stroke and actual use of these resources. METHODS: Six and twelve months after stroke, 84 patients and their nearest others were questioned concerning their acquaintance with and use of professional and institutional resources for support and also with respect to social support and self-efficacy. RESULTS: Six and twelve months after stroke, actual use of the various resources for support varied between 0 and 13%. Only part of the patients (11-65%) and relatives (up to 78%) knew about the professional and institutional resource available. DISCUSSION: Information about resources for support after stroke is unsatisfactory and should be established at a point in the delivery of care chain where all those affected by stroke and their caregivers are accessed. 相似文献
109.
Background One of the most popular robot assisted rehabilitation devices used is the Lokomat. Unfortunately, not much is known about the behaviors exhibited by subjects in this device. The goal of this study was to evaluate the kinematic patterns of individuals walking inside the Lokomat compared to those demonstrated on a treadmill.Methods Six healthy subjects walked on a treadmill and inside the Lokomat while the motions of the subject and Lokomat were tracked. Joint angles and linear motion were determined for Lokomat and treadmill walking. We also evaluated the variability of the patterns, and the repeatability of measuring techniques.Findings The overall kinematics in the Lokomat are similar to those on a treadmill, however there was significantly more hip and ankle extension, and greater hip and ankle range of motion in the Lokomat (P < 0.05). Additionally, the linear movement of joints was reduced in the Lokomat. Subjects tested on repeated sessions presented consistent kinematics, demonstrating the ability to consistently setup and test subjects.Interpretation The reduced degrees of freedom in the Lokomat are believed to be the reason for the specific kinematic differences. We found that despite being firmly attached to the device there was still subject movement relative to the Lokomat. This led to variability in the patterns, where subjects altered their gait pattern from step to step. These results are clinically important as a variable step pattern has been shown to be a more effective gait training strategy than one which forces the same kinematic pattern in successive steps. 相似文献
110.
Yeung TS Wessel J Stratford PW MacDermid JC 《The Journal of orthopaedic and sports physical therapy》2008,38(7):410-417
STUDY DESIGN: Single-group repeated-measures study. OBJECTIVE: To examine the test-retest reliability of the timed up and go (TUG) test and its validity for measuring change and predicting length of stay (LOS) on an inpatient orthopaedic rehabilitation ward. BACKGROUND: The TUG test is used to measure functional mobility of persons with musculoskeletal conditions but it has not been thoroughly tested for use in an inpatient orthopaedic rehabilitation ward. METHODS AND MEASURES: The TUG test was administered to 142 patients on admission to an orthopaedic rehabilitation ward 7 to 10 days after admission and on discharge. To test reliability, 24 subjects had these tests repeated 1 day after admission, and the intraclass correlation (ICC) and standard error of measurement (SEM) were calculated. Change scores of the TUG test were evaluated against change scores in pain and function, and the rating of improvement of the patient and therapist. The standardized response mean (SRM) was also calculated. A regression analysis was performed to determine whether the admission TUG test score could predict LOS. RESULTS: The ICC of the TUG test was 0.80 and the SEM was 10.2 seconds. The change in TUG test scores correlated with the changes in pain (r = 0.21, P<.01) and function (r = -0.23, P<.01), and resulted in an SRM of 0.89 for subjects rated as improved. The admission TUG test scores accounted for only 3.4% of the variance in inpatient LOS. CONCLUSION: The TUG test is reliable and valid to assess group change of inpatients on an orthopaedic rehabilitation ward but is not a good predictor of LOS. LEVEL OF EVIDENCE: Prognosis, level 1b. 相似文献