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排序方式: 共有893条查询结果,搜索用时 5 毫秒
101.
Millan MJ Loiseau F Dekeyne A Gobert A Flik G Cremers TI Rivet JM Sicard D Billiras R Brocco M 《The Journal of pharmacology and experimental therapeutics》2008,324(3):1212-1226
In contrast to clinically available antipsychotics, the novel benzopyranopyrrolidine derivative, S33138 (N-[4-[2-[(3aS,9bR)-8-cyano-1,3a,4,9b-tetrahydro[1]benzopyrano[3,4-c]pyrrol-2(3H)-yl)-ethyl]phenyl-acetamide), behaves as a preferential antagonist of D(3) versus D(2) receptors and does not interact with histamine H(1) and muscarinic receptors. In contrast to haloperidol, clozapine, olanzapine, and risperidone, S33138 (0.16-2.5 mg/kg s.c.) did not disrupt performance in passive-avoidance and five-choice serial reaction time procedures. Furthermore, upon either systemic administration (0.04-2.5 mg/kg s.c.) or introduction into the frontal cortex (0.04-0.63 mug/side), S33138 potently attenuated the perturbation of social recognition by scopolamine or a prolonged intersession delay. Over a comparable and low-dose range, S33138 (0.04-0.63 mg/kg s.c.) elevated dialysis levels of acetylcholine in the frontal cortex of freely moving rats. At higher doses (2.5-10.0 mg/kg s.c.), S33138 also increased frontocortical levels of histamine, whereas monoamines, glutamate, glycine, and GABA were unaffected. By analogy to the other antipsychotics, S33138 (0.63-10.0 mg/kg s.c.) inhibited conditioned avoidance responses in rats, apomorphine-induced climbing in mice, and hyperlocomotion elicited by amphetamine, cocaine, dizocilpine, ketamine, and phencyclidine in rats. S33138 (0.16-2.5 mg/kg s.c.) also blocked the reduction of prepulse inhibition elicited by apomorphine. In comparison with the above actions, only "high" doses of S33138 (10.0-40.0 mg/kg s.c.) elicited catalepsy. To summarize, reflecting preferential blockade of D(3) versus D(2) receptors, S33138 preserves and/or enhances cognitive function, increases frontocortical cholinergic transmission, and is active in models of antipsychotic properties at doses well below those inducing catalepsy. In comparison with clinically available agents, S33138 displays, thus, a distinctive and promising profile of potential antipsychotic properties. 相似文献
102.
The present paper describes the development of a model linking the optical density of a radiographic film to the applied dose. This model takes into account the kind of bremsstrahlung used in radiotherapy, and uses fewer parameters compared with the models developed so far. The measurements showed an influence of the field size on the model parameters. Monte Carlo simulations showed that different field sizes and depths in solid water can change the spectral distributions. The spectrum hardens with decreasing field size and increasing depth in phantom material. This has an influence on the model parameters. Nevertheless, the model can still be used to describe the relation between optical density and applied dose for films that are irradiated with fields of different size. A dose-rate dependence was not observed. The size and form of the fields used in calibration and application can therefore cause a systematic error in verification with film. 相似文献
103.
104.
A. J. H. Cremers F. Hagen P. W. M. Hermans J. F. Meis G. Ferwerda 《European journal of clinical microbiology & infectious diseases》2014,33(7):1119-1124
Detection of pneumococcal DNA in blood could be a fast alternative for blood culture in invasive pneumococcal disease (IPD). In this study we compared the diagnostic value of the serum pneumococcal DNA load between different clinical syndromes in adults with bacteremic pneumococcal infections, also after initiation of antibiotic treatment. Adults hospitalized with a blood culture proven pneumococcal infection between December 2008 and June 2013 were retrospectively included. Pneumococcal DNA loads in corresponding serum samples were determined by qPCR. Data on clinical diagnosis, course of disease and antibiotic treatment were extracted from medical records. For 53 IPD cases eligible stored serum samples were retrieved. The proportion of samples positive in qPCR was lower in uncomplicated pneumonia compared with other clinical syndromes (59.5 % vs. 100 %, p?=?0.005). The pneumococcal DNA load was higher in cases other than uncomplicated pneumonia (p?=?0.043) as well as in more severe disease (p-values 0.018, 0.029 and 0.003 for PSI Risk Class IV/V, ICU admission and mortality, respectively). Both detection of pneumococcal DNA and distribution of load did not significantly change over the first days of hospitalization despite treatment with appropriate antibiotics. Detection of pneumococcal DNA in serum was more sensitive in clinical syndromes other than uncomplicated pneumonia. Furthermore, the pneumococcal DNA load was associated with the type of IPD and severity of disease. Since the serum pneumococcal DNA load seemed unaffected by antibiotic treatment during the first days of IPD, it may offer an alternative for culture methods after prior antibiotic use. 相似文献
105.
Hans Heemskerk Christa de Winter Petra van Kuik Niki Heuvelmans Patrizia Sabatelli Paola Rimessi Paola Braghetta Gert-Jan B van Ommen Sjef de Kimpe Alessandra Ferlini Annemieke Aartsma-Rus Judith CT van Deutekom 《Molecular therapy》2010,18(6):1210-1217
Antisense oligonucleotides (AONs) are being developed as RNA therapeutic molecules for Duchenne muscular dystrophy. For oligonucleotides with the 2′-O-methyl-phosphorothioate (2OMePS) RNA chemistry, proof of concept has been obtained in patient-specific muscle cell cultures, the mouse and dog disease models, and recently by local administration in Duchenne patients. To further explore the pharmacokinetic (PK)/pharmacodynamic (PD) properties of this chemical class of oligonucleotides, we performed a series of preclinical studies in mice. The results demonstrate that the levels of oligonucleotides in dystrophin-deficient muscle fibers are much higher than in healthy fibers, leading to higher exon-skipping levels. Oligonucleotide levels and half-life differed for specific muscle groups, with heart muscle showing the lowest levels but longest half-life (~46 days). Intravenous (i.v.), subcutaneous (s.c.), and intraperitoneal (i.p.) delivery methods were directly compared. For each method, exon-skipping and novel dystrophin expression were observed in all muscles, including arrector pili smooth muscle in skin biopsies. After i.v. administration, the oligonucleotide peak levels in plasma, liver, and kidney were higher than after s.c. or i.p. injections. However, as the bioavailability was similar, and the levels of oligonucleotide, exon-skipping, and dystrophin steadily accumulated overtime after s.c. administration, we selected this patient-convenient delivery method for future clinical study protocols. 相似文献
106.
107.
A. Cohen R. R. Recker J. Lappe D. W. Dempster S. Cremers D. J. McMahon E. M. Stein J. Fleischer C. J. Rosen H. Rogers R. B. Staron J. LeMaster E. Shane 《Osteoporosis international》2012,23(1):171-182
Introduction
In men, idiopathic osteoporosis (IOP) is often associated with low serum insulin-like growth factor (IGF-1) and reduced bone formation. The characteristics of premenopausal women with IOP are not well defined. We aimed to define the clinical, reproductive, and biochemical characteristics of premenopausal women with unexplained osteoporosis.Methods
This is a cross-sectional study of 64 women with unexplained osteoporosis, 45 with fragility fractures, 19 with low bone mineral density (BMD; Z-score less than or equal to ?2.0) and 40 normal controls. The following are the main outcome measures: clinical and anthropometric characteristics, reproductive history, BMD, gonadal and calciotropic hormones, IGF-1, and bone turnover markers (BTMs).Results
Subjects had lower BMI and BMD than controls, but serum and urinary calcium, serum estradiol, vitamin D metabolites, IGF-1, and most BTMs were similar. Serum parathyroid hormone (PTH) and the resorption marker, tartrate-resistant acid phosphatase (TRAP5b), were significantly higher in both groups of subjects than controls and directly associated in all groups. Serum IGF-1 and all BTMs were directly associated in controls, but the association was not significant after controlling for age. There was no relationship between serum IGF-1 and BTMs in subjects. There were few differences between women with fractures and low BMD.Conclusions
Higher serum TRAP5b and PTH suggest that increased bone turnover, possibly related to subclinical secondary hyperparathyroidism could contribute to the pathogenesis of IOP. The absence of differences between women with fractures and those with very low BMD indicates that this distinction may not be clinically useful to categorize young women with osteoporosis. 相似文献108.
Anne M L C Bischoff Patrick L M Huygen Martijn H Kemperman Ronald J E Pennings Steven J H Bom Wim I M Verhagen Ronald J C Admiraal Hannie Kremer Cor W R J Cremers 《Otology & neurotology》2005,26(5):918-925
OBJECTIVES: To analyze cochleovestibular impairment features in P51S COCH mutation carriers (n = 22) in a new, large Dutch family and to compare the results to those obtained in previously identified similar mutation carriers (n = 52). To evaluate age-related features between progressive hearing and vestibular impairment of all mutation carriers (n = 74). STUDY DESIGN: Family study. METHODS: Regression analysis was performed in relation to age to outline the development of hearing thresholds, speech recognition scores, and vestibulo-ocular reflex time constant as the key vestibular response parameter. RESULTS: Pure tone thresholds, phoneme recognition scores, and vestibular responses of the mutation carriers in the new family were essentially similar to those previously established in all other mutation carriers. Hearing started to deteriorate in all mutation carriers from 43 years of age onwards, whereas deterioration of vestibular function started from age 34. CONCLUSION: Vestibular impairment starts earlier, progresses more rapidly, and, eventually, is more complete than hearing impairment in P51S COCH mutation carriers. 相似文献
109.
Wagenaar M Draaijer P Meek H ten Donkelaar HJ Wesseling P Kimberling W Cremers C 《International journal of pediatric otorhinolaryngology》1999,50(3):185-195
Hypothesis: Does long-term sound deprivation lead to degeneration of the cochlear nuclei in two Usher type I patients? Methods: The cochlear nuclei of these patients were morphometrically analyzed and compared with two age-matched controls. Routine autopsy of the brainstems was performed before the design of this study was known. During this procedure, the ventral cochlear nucleus (VCN) can easily be damaged. Five partially damaged VCN could nevertheless be analyzed for this study, including the right VCN of Usher patient I and both VCN of Usher patient 2. Using 15 μm thick serial paraffine sections of the cochlear nuclei, estimates of volume, neuronal densities, number of cells and mean cell diameter of the dorsal cochlear nucleus (DCN) and VCN were obtained. Results: This study presents unique material of the cochlear nuclei in two patients with Usher syndrome type I. Data regarding volume and total cell number of the VCN are influenced by the absence of a part of the VCN. Results suggest a decrease in mean cell diameter of the VCN in Usher patients. Other parameters of the VCN and DCN, however, showed no major differences between Usher type I patients and controls. Conclusion: Only minor degenerative changes are apparent in the cochlear nuclei of two patients with Usher type I, who were deprived of acoustic stimuli since birth. 相似文献
110.
Between 1964 and 1986, 104 ears of 86 patients with a minor congenital ear anomaly underwent an exploratory tympanotomy at the Institute of Otorhinolaryngology of the University Hospital Nijmegen. A classification of these anomalies is proposed based on the surgical findings and results. The 4 groups in this classification are: isolated stapes ankylosis, stapes ankylosis associated with an anomaly of the malleus and incus, an isolated anomaly of the malleus and incus with a mobile stapes footplate and finally, aplasia of the oval and/or round window. In a total of 29 ears (22 patients) out of these 104 ears, the anomaly formed part of a syndrome. The various syndromes and the anomalies encountered are discussed. The impact of a syndromal diagnosis on the outcome of reconstructive ear surgery is discussed per syndrome. 相似文献