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971.
972.
The influence of the mother tongue on vowel productions in infancy is different for deaf and hearing babies. Audio material of five hearing and five deaf infants acquiring Dutch was collected monthly from month 5-18, and at 24 months. Fifty unlabelled utterances were digitized for each recording. This study focused on developmental paths in vowel productions. The applied automated band filtering analysis is F0-independent and results in a spectral envelope, sampled in a 40-dimensional space. Via a Principal Component Analysis (PCA, data reduction), a vowel space for normally hearing 2-year-olds was constructed, enabling the projection of the individual developmental data of the infants in a two-dimensional reference plane. Comparison of the results for the hearing and the deaf infants over 2 years indicates individual as well as group differences. The amount of hearing loss as well as the communication styles seem to be important factors in explaining differences between the infant categories. 相似文献
973.
974.
Bertagnolio S Derdelinckx I Parker M Fitzgibbon J Fleury H Peeters M Schuurman R Pillay D Morris L Tanuri A Gershy-Damet GM Nkengasong J Gilks CF Sutherland D Sandstrom P 《Antiviral therapy》2008,13(Z2):49-57
With rapidly increasing access to antiretroviral drugs globally, HIV drug resistance (HIVDR) has become a significant public health issue. This requires a coordinated and collaborative response from country level to international level to assess the extent of HIVDR and the establishment of efficient and evidence-based strategies to minimize its appearance and onward transmission. In parallel with the rollout of universal access to HIV treatment, countries are developing protocols based on the recommendations of the World Health Organization (WHO) to measure, at a population level, both transmitted HIVDR and HIVDR emerging during treatment. The WHO in collaboration with international experts (HIVResNet Laboratory Working Group), has developed a laboratory strategy, which has the overall goal of delivering quality-assured HIV genotypic results on specimens derived from the HIVDR surveys. The results will be used to help control the emergence and spread of drug resistance and to guide decision makers on antiretroviral therapy policy at national, regional and global level. The HIVDR Laboratory Strategy developed by the WHO includes several key aspects: the formation of a global network of national, regional and specialized laboratories accredited to perform HIVDR testing using a common set of WHO standard and performance indicators; recommendations of acceptable methods for collection, handling, shipment and storage of specimens in field conditions; and the provision of laboratory technical support, capacity building and quality assurance for network laboratories. The WHO/HIVResNet HIVDR Laboratory Network has been developed along the lines of other successful laboratory networks coordinated by the WHO. As of August 2007, assessment for accreditation has been conducted in 30 laboratories, covering the WHO's African, South-East Asia, Western Pacific, and the Caribbean Regions. 相似文献
975.
976.
Peeters PH Lukanova A Allen N Berrino F Key T Dossus L Rinaldi S van Gils CH Bueno-de-Mesquita HB Boeing H Schulz M Chang-Claude J Linseisen J Panico S Sacerdote C Palli D Tumino R Trichopoulou A Trichopolos D Bamia C Larranaga N Ardanaz E Pera G Quirós JR Martínez-García C Navarro C Bingham SA Khaw KT Clavel F Tjonneland A Olsen A Overvad K Tetsche MS Lund E Lundin E Berglund G Riboli E Kaaks R 《Endocrine-related cancer》2007,14(1):81-90
We set out to study the relationship between circulating levels of IGF-I and its major binding protein (IGFBP-3) in relation to ovarian cancer risk. We conducted a case-control study nested within the European Prospective Investigation into Cancer and Nutrition. Levels of IGF-I and IGFBP-3 were measured in prediagnostic serum samples of 214 women who subsequently developed ovarian cancer, and 388 matched control subjects. Conditional logistic regression models were used to estimate relative risks of ovarian cancer by tertiles of IGF-I and IGFBP-3 levels. For all women, there was no association between the circulating IGF-I or IGFBP-3 levels and the risk of ovarian cancer. However, among women diagnosed with ovarian cancer aged 55 or younger, the relative risk was higher in the middle or top tertiles of serum IGF-I, when compared with women in the lowest tertile (odds ratios (OR) = 1.8 (95%CI 0.7-4.3) and OR = 2.4 (95%CI 0.9-6.4); P(trend) = 0.08) respectively. These results were adjusted for body mass index, previous hormone use, fertility problems, and parity. Restricting the analysis to women who were premenopausal at blood donation, relative risks for ovarian cancer diagnosed before age 55 were higher (OR = 5.1 (95%CI 1.5-18.2) and OR = 5.6 (95%CI 1.5-20.8) respectively, for second and third tertiles; P(trend) = 0.02). Adjustment for serum IGFBP-3 levels only slightly attenuated relative risk estimates. Relations between IGFBP-3 and ovarian cancer before age 55 were in the same direction as for IGF-I, but less strong and statistically not significant. In women aged over 55, there was no association between serum IGF-I or IGFBP-3 and ovarian cancer risk. Our results suggest that the circulating levels of IGF-I may play a potentially important role in the development of ovarian cancer in women of a pre- or perimenopausal age. 相似文献
977.
van den Berg MH Ronday HK Peeters AJ Voogt-van der Harst EM Munneke M Breedveld FC Vliet Vlieland TP 《Rheumatology (Oxford, England)》2007,46(3):545-552
OBJECTIVE: To assess the engagement in and satisfaction with an Internet-mediated physical activity intervention with individual supervision in patients with rheumatoid arthritis (RA). METHODS: The intervention studied was one of the two strategies aimed at enhancing physical activity in RA patients that were being compared in a randomized controlled trial. A total of 82 patients, all experienced in using Internet and e-mail and registered at three different rheumatology out-patient clinics, were randomly allocated to the Internet-mediated individualized intervention (52 weeks). They had access to personal physical activity schedules and received individual supervision by a physical therapist by means of weekly e-mail feedback. In addition, telephone contacts, an online discussion forum, six face-to-face group meetings and electronic newsletters were offered. Besides registration of returned physical activity schedules, engagement and satisfaction were measured through questionnaires. RESULTS: The median physical activity schedule return rate of the 82 participants was 55%. The mean number of patients logging into the website at least once a week was 53 (70%) over 12 months. Of all patients, 69 returned the questionnaires (response 84%). Telephone contacts were used by 38/67 patients (57%), the mean (SD) number of attended group meetings was 3.1 (1.5) and the discussion forum comprised 15 posted messages. Overall, the proportions of patients being (very) satisfied with the amount of e-mail contacts, telephone contacts, usefulness of website information, physical activity schedules, group meetings and website layout were >/=85%. A smaller proportion of patients were satisfied with the links to other websites (68%), the newsletters (55%) and the online discussion forum (32%). CONCLUSION: Physical activity schedules with weekly feedback by e-mail, telephone contacts and a limited number of group meetings were frequently used website tools and modes of communication of an Internet-based physical activity intervention, with high-satisfaction rates from RA patients. Discussion forum and newsletters were less used and appreciated. Caution should be taken when extrapolating the results found to groups of patients who are not experienced Internet and e-mail users or patients with more severe physical disabilities. 相似文献
978.
van Bergen JE Kerssens JJ Schellevis FG Sandfort TG Coenen TT Bindels PJ 《International journal of STD & AIDS》2007,18(6):374-379
Health-care seeking behaviour for sexually transmitted infection (STI)-related symptoms is not well known in the Netherlands. Within the framework of a large representative study, the second National Survey of General Practice (NIVEL 2001), 9687 persons aged 18 years and older were interviewed about their STI and STI-related health-care seeking behaviour. In total, 1.2% of the interviewees reported STI-related symptoms in the past year (18-24 years: 5%). A (lifetime) history of STI was reported by 2.7% (18-44 years: 4%). In all, 63% of interviewees visited their general practitioner (GP) for these complaints; 20% went to an STI-clinic and/or municipal public health services and 8% to a different care-provider. A total of 9% did not undertake any action. The majority of persons with STI-related symptoms in the Netherlands visit the GP. Reported history of STI-related symptoms was twice lower in the Netherlands compared with the UK National Sexual Health Survey. Appropriate attention for sexual health in primary care is needed. 相似文献
979.
Polydipsia and water intoxication (PWI) seem to be associated with a particular form of schizophrenia, first described by Kraepelin, involving negative symptoms, disorganization and poor outcome. In this study, a group of 20 schizophrenic patients with PWI was selected and matched for age, duration of illness and gender with a group of 20 schizophrenic controls with no PWI. For these patients the following measure were obtained: clinical and demographic data, Keefe's criteria for Kraepelinian schizophrenia, the Positive and Negative Syndrome Scale score and the score on Fagerstr?m's Nicotine Dependence Scale. The group of schizophrenic patients with PWI presents significantly higher levels of negative symptoms, disorganized symptoms and general symptoms of psychopathology, and it is composed of a significantly higher percentage of Kraepelinian patients. These results show an association of polydipsia and water intoxication with Kraepelinian schizophrenia suggesting physiological hypotheses for a specific pathogenic pathway. 相似文献
980.
Liver fibrosis: noninvasive assessment with MR elastography versus aspartate aminotransferase-to-platelet ratio index 总被引:8,自引:0,他引:8
Huwart L Sempoux C Salameh N Jamart J Annet L Sinkus R Peeters F ter Beek LC Horsmans Y Van Beers BE 《Radiology》2007,245(2):458-466
PURPOSE: To prospectively compare the sensitivity and specificity of magnetic resonance (MR) elastography with those of the routinely available aspartate aminotransferase-to-platelet ratio index (APRI) test for staging hepatic fibrosis in patients who have undergone liver biopsy for suspicion of chronic liver disease, with histopathologic examination as the reference standard. MATERIALS AND METHODS: The study was approved by the ethics committee. All patients gave written informed consent. Eighty-eight patients (37 men, 51 women; mean age, 54.0 years +/- 13.1 [standard deviation]) who underwent liver biopsy for suspicion of chronic liver disease underwent MR elastography and APRI testing within 2 days after liver biopsy. At histopathologic examination, the fibrosis stage was assessed according to METAVIR scores (fibrosis scores F0 [no fibrosis] to F4 [cirrhosis]). MR elastography was performed by transmitting mechanical waves within the liver and measuring the small cyclic displacement of the liver spins with a phase-contrast spin-echo sequence. The performances of MR elastography and APRI testing were assessed, and the optimal cutoff values for fibrosis stage were determined with receiver operating characteristic (ROC) curve analysis. RESULTS: At MR elastography, areas under the ROC curves (A(z)) for elasticity and viscosity, respectively, were 0.999 and 0.863 at fibrosis scores greater than or equal to F2, 0.997 and 0.962 at scores greater than or equal to F3, and 1.000 and 0.986 at score F4. A(z) values for elasticity at MR were significantly larger than those for the APRI (0.854 at scores > or = F2, P < .001; 0.886 at scores > or = F3, P = .003; and 0.851 at score F4, P = .004). Optimal cutoff values of elasticity were 2.5 kPa for fibrosis scores greater than or equal to F2, 3.1 kPa for scores greater than or equal to F3, and 4.3 kPa for score F4. CONCLUSION: Large A(z) values for elasticity (>0.990 for scores > or = F2, > or = F3, and F4) show that MR elastography was accurate in liver fibrosis staging and superior to biochemical testing with APRIs. 相似文献