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61.
Touchette E Petit D Paquet J Boivin M Japel C Tremblay RE Montplaisir JY 《Archives of pediatrics & adolescent medicine》2005,159(3):242-249
OBJECTIVE: To identify the factors most strongly associated with sleeping less than 6 consecutive hours at night for children aged 5, 17, and 29 months. DESIGN, SETTING, AND PARTICIPANTS: A randomized survey design used a representative sample of infants born in 1997-1998 in the Canadian province of Quebec. Data were collected by questionnaires and interviews. Interviews were scheduled at home with the mothers. The number of consecutive hours slept at night by 1741 children aged 5, 17, and 29 months was assessed from parental reports. Factors associated with fragmented sleep were investigated for each age in a cross-sectional design. RESULTS: At 5 months of age, 23.5% of children did not sleep 6 consecutive hours. Of the children who did not sleep 6 consecutive hours at night at 5 months or 17 months of age, 32.9% were still not sleeping 6 consecutive hours at night at 29 months of age. The factor most strongly associated with not sleeping at least 6 consecutive hours per night at 5 months of age was feeding the child after an awakening. Parental presence until sleep onset was the factor most strongly associated with not sleeping at least 6 consecutive hours per night at 17 months and 29 months of age. CONCLUSIONS: Sleep consolidation evolves rapidly in early childhood. Parental behaviors at bedtime and in response to a nocturnal awakening are highly associated with the child's sleep consolidation. The effects are probably bidirectional and probably create a long-term problem. Early interventions could possibly break the cycle. 相似文献
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Bourthoumieu S Esclaire F Terro F Fiorenza M Eyraud JL Servaud M Cantaloube M Fermeaux V Yardin C 《Prenatal diagnosis》2004,24(3):219-223
We describe two cases of sonographic abnormalities associated with unusual chromosomal aberrations. Case 1 presented with a cystic hygroma at 12 weeks' gestation. Cytogenetic analysis revealed an unbalanced complex chromosome rearrangement implicating chromosomes 6, 13 and 21 (karyotype: 47,XX,t(6;21;14)(q14;q21;q21)mat,+21) and corresponding to a complete trisomy 21. This anomaly resulted from malsegregation of a maternal balanced three-way translocation. For case 2, an alobar holoprosencephaly was identified by ultrasonography at 23 weeks' gestation. Chromosomal analysis showed a recombinant rec (13), dup q chromosome, secondary to unequal crossing-over of a paternal pericentric inversion of chromosome 13, giving rise to partial trisomy 13q (karyotype: 46,XX,rec(13)dup(13q)inv(13)(p11q21)pat). These two cases illustrate the role of ultrasound in leading to detection not only of foetal chromosomal aberrations but also of rare balanced chromosomal rearrangements presented by one of the two parents. 相似文献
65.
Pregnancy and Delivery After Stimulation with rFSH of a Galatosemia Patient Suffering Hypergonadotropic Hypogonadism: Case Report 总被引:3,自引:0,他引:3
Menezo YJ Lescaille M Nicollet B Servy EJ 《Journal of assisted reproduction and genetics》2004,21(3):89-90
PURPOSE: To determine if hypergonadotropic hypogonadism related to galactosemia could be linked to anomaly of the circulating FSH. A 26-year-old woman, suffering GALT (Galactoso-1-phosphate uridyltransferase) had a premature ovarian failure with amenorrhea since the age of 19. The circulating level for FSH was 83 and 34 mU/mL for LH. METHODS: After treatment with a hormonal substitution cycle including estradiol and progesterone, the patient underwent stimulations with recombinant FSH. The first cycle, one 16-mm diameter follicle and the second cycle one follicle of 17.5 mm of diameter were obtained at the time of ovulation induction. RESULTS: The patient conceived and delivered a female baby weighting 3.38 kg after the second stimulation protocol. CONCLUSIONS: The impact of galactosemia on the ovary seems rather related to the absence of recognition of circulating FSH by its receptor and not to a toxic alteration of the ovary by itself as it is currently reported. The rFSH treatment following hormonal substitution cycles allows to overcome infertility problems. 相似文献
66.
Predictive conceptual models help us frame research questions, interpret results, and guide clinical practice. Although numerous models have appeared in the assistive technology (AT) literature, none has been shown to predict AT usage. The lack of a valid predictive model indicates the need for development of new approaches to modeling AT outcomes. This article proposes a user-centered conceptual model that predicts AT usage as a function of the perceived relative advantages of AT. Device usage is not modeled as a one-time, all-or-nothing proposition, but as a decision process recurring over time. The influence of parallel interventions working concurrently with, or as an alternative to, AT is a central consideration that ultimately drives AT usage. Usage is shown as a proximal influence on AT impact, and AT impact is shown to be a predictor of future use. Research is cited supporting various elements of the new model. 相似文献
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Robidoux PY Gong P Sarrazin M Bardai G Paquet L Hawari J Dubois C Sunahara GI 《Ecotoxicology and environmental safety》2004,58(3):300-313
Explosives are released into the environment at production and processing facilities, as well as through field use. These compounds may be toxic at relatively low concentrations to a number of ecological receptors. A toxicity assessment was carried out on soils from an explosive-contaminated site at a Canadian Forces Area Training Center. Toxicity studies on soil organisms using endpoints such as microbial processes (potential nitrification activity, dehydrogenase activity, substrate-induced respiration, basal respiration), plant seedling and growth (Lactuca sativa and Hordeum vulgare), and earthworm (Eisenia andrei) growth and reproduction were carried out. Results showed that 1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane (HMX) was the principal polynitro-organic compound measured in soils. Soils from the contaminated site decreased microbial processes and earthworm reproduction; whereas plant growth was not significantly reduced. Toxicity to aquatic organisms and genotoxicity were also assessed on soil elutriates using Microtox (Vibrio fischeri), growth inhibition of algae (Selenastrum capricornutum), and SOS Chromotest (Escherichia coli). Results indicated that soil elutriates were generally not toxic to bacteria (Microtox) and algae. However, genotoxicity was found in a number of soil elutriate samples. Thus, the explosive-contaminated soils from the antitank firing range may represent a hazard for the soil organisms. Nevertheless, the global toxicity might have partially resulted from HMX as well as from other (not identified) contaminants such as heavy metals. 相似文献
70.
Classe JM Loussouarn D Campion L Fiche M Curtet C Dravet F Pioud R Rousseau C Resche I Sagan C 《Cancer》2004,100(5):935-941
BACKGROUND: Previous reports have shown that regional lymph node involvement in patients with early-stage breast carcinoma can be evaluated by resection of axillary sentinel lymph nodes (ASLN). Axillary lymphadenectomy may be unnecessary in the absence of ASLN involvement. In the current study, the authors compared the results of ASLN resection in patients with lobular invasive carcinoma (LIC) with the results from patients with ductal invasive carcinoma (DIC) in terms of detection rates and false-negative rates. METHODS: For ASLN detection, technetium 99m sulfur-colloid and patent blue were injected around the tumor. Each patient underwent both ASLN resection and complete axillary lymphadenectomy. Detection rates and false-negative rates were evaluated in patients with LIC and in patients with DIC. RESULTS: Two hundred forty-three patients with invasive, early-stage breast carcinoma were enrolled in the study (208 patients with DIC and 35 patients with LIC). The median patient age, pathologic tumor size, hormone receptor status, and rates of involved lymph nodes were equivalent for both groups. ASLN detection and false-negative rates did not differ for patients with LIC and patients with DIC. CONCLUSIONS: The ASLN detection rate was not dependent on the pathologic type of invasive carcinoma. Pathologic examination of ASLN in patients with LIC and in patients with DIC predicted axillary lymph node status with the same predictive value in terms of lymph node metastasis. For patients with LIC, ASLN examination overestimated the rate of micrometastasis as diagnosed by immunohistochemical techniques. These results will require confirmation in larger studies. 相似文献