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41.
WHO Child Growth Standards based on length/height, weight and age   总被引:18,自引:0,他引:18  
Aim: To describe the methods used to construct the WHO Child Growth Standards based on length/height, weight and age, and to present resulting growth charts. Methods: The WHO Child Growth Standards were derived from an international sample of healthy breastfed infants and young children raised in environments that do not constrain growth. Rigorous methods of data collection and standardized procedures across study sites yielded very high-quality data. The generation of the standards followed methodical, state-of-the-art statistical methodologies. The Box-Cox power exponential (BCPE) method, with curve smoothing by cubic splines, was used to construct the curves. The BCPE accommodates various kinds of distributions, from normal to skewed or kurtotic, as necessary. A set of diagnostic tools was used to detect possible biases in estimated percentiles or z-score curves. Results: There was wide variability in the degrees of freedom required for the cubic splines to achieve the best model. Except for length/height-for-age, which followed a normal distribution, all other standards needed to model skewness but not kurtosis. Length-for-age and height-for-age standards were constructed by fitting a unique model that reflected the 0.7-cm average difference between these two measurements. The concordance between smoothed percentile curves and empirical percentiles was excellent and free of bias. Percentiles and z-score curves for boys and girls aged 0–60 mo were generated for weight-for-age, length/height-for-age, weight-for-length/height (45 to 110 cm and 65 to 120 cm, respectively) and body mass index-for-age.
Conclusion: The WHO Child Growth Standards depict normal growth under optimal environmental conditions and can be used to assess children everywhere, regardless of ethnicity, socio-economic status and type of feeding.  相似文献   
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The diverse composition and structure of extracellular matrix (ECM) interfaces encountered by tumor cells at secondary tissue sites can influence metastatic progression. Extensive in vitro and in vivo data has confirmed that metastasizing tumor cells can adopt different migratory modes in response to their microenvironment. Here we present a model that uses human stromal cell-derived matrices to demonstrate that plasticity in tumor cell movement is controlled by the tumor-associated collagen receptor Endo180 (CD280, CLEC13E, KIAA0709, MRC2, TEM9, uPARAP) and the crosslinking of collagen fibers by stromal-derived lysyl oxidase (LOX). Human osteoblast-derived and fibroblast-derived ECM supported a rounded ‘amoeboid-like’ mode of cell migration and enhanced Endo180 expression in three prostate cancer cell lines (PC3, VCaP, DU145). Genetic silencing of Endo180 reverted PC3 cells from their rounded mode of migration towards a bipolar ‘mesenchymal-like’ mode of migration and blocked their translocation on human fibroblast-derived and osteoblast-derived matrices. The concomitant decrease in PC3 cell migration and increase in Endo180 expression induced by stromal LOX inhibition indicates that the Endo180-dependent rounded mode of prostate cancer cell migration requires ECM crosslinking. In conclusion, this study introduces a realistic in vitro model for the study of metastatic prostate cancer cell plasticity and pinpoints the cooperation between tumor-associated Endo180 and the stiff microenvironment imposed by stromal-derived LOX as a potential target for limiting metastatic progression in prostate cancer.  相似文献   
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BackgroundLack of time, lack of familiarity with root cause analysis, or suspicion that the reporting may result in negative consequences hinder involvement in the analysis of safety incidents and the search for preventive actions that can improve patient safety.ObjectiveThe aim was develop a tool that enables hospitals and primary care professionals to immediately analyze the causes of incidents and to propose and implement measures intended to prevent their recurrence.MethodsThe design of the Web-based tool (BACRA) considered research on the barriers for reporting, review of incident analysis tools, and the experience of eight managers from the field of patient safety. BACRA’s design was improved in successive versions (BACRA v1.1 and BACRA v1.2) based on feedback from 86 middle managers. BACRA v1.1 was used by 13 frontline professionals to analyze incidents of safety; 59 professionals used BACRA v1.2 and assessed the respective usefulness and ease of use of both versions.ResultsBACRA contains seven tabs that guide the user through the process of analyzing a safety incident and proposing preventive actions for similar future incidents. BACRA does not identify the person completing each analysis since the password introduced to hide said analysis only is linked to the information concerning the incident and not to any personal data. The tool was used by 72 professionals from hospitals and primary care centers. BACRA v1.2 was assessed more favorably than BACRA v1.1, both in terms of its usefulness (z=2.2, P=.03) and its ease of use (z=3.0, P=.003).ConclusionsBACRA helps to analyze incidents of safety and to propose preventive actions. BACRA guarantees anonymity of the analysis and reduces the reluctance of professionals to carry out this task. BACRA is useful and easy to use.  相似文献   
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Objective. The aim of this study was to compare the efficacy of different dentine adhesives in delaying the coronal bacterial leakage of Enterococcus faecalis in filled root canals. Materials and methods. Ninety-five lower incisors of patients >65 years of age were instrumented using the ProTaper® system and were irrigated with 1 mL of 2.5% sodium hypochlorite (NaOCl) alternated with 1 mL 17% EDTA between each file change. Final irrigation was performed with 5 mL of 17% EDTA and then flushed with 5 mL of distilled water. The teeth were randomly divided into five experimental groups (n = 15/group) and one of the following dentine adhesives was applied: (1) AdheSE®; (2) Excite® DSC; (3) Clearfil? Protect Bond; (4) One Coat 7.0; or (5) Control group without adhesive. After filling the root canals, the samples were mounted on a double chamber device to evaluate the bacterial filtration of E. faecalis during a period of 240 days. The results underwent non-parametric Kaplan-Meier survival analysis and comparisons among groups were done using the Log-Rank test. Results. At 240 days, E. faecalis was detected in samples of all groups in the lower chamber. The highest survival value was obtained by One Coat 7.0, giving statistically significant differences from the other groups, whereas Clearfil? Protect Bond, AdheSE® and Excite® DSC showed similar behaviours, likewise similar to the Control group. Conclusions. One Coat 7.0 adhesive system provides the longest survival value to delay E. faecalis coronal leakage in filled root canals.  相似文献   
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Development of metastasis in peripheral tissues is a major problem in the fight to cure breast cancer. Although it is becoming evident that chronic inflammation can contribute to tumor progression and metastasis, the effect of acute inflammation in primary tumor is less known. Using mouse models for breast cancer here we show that biopsy of mammary tumors increases the frequency of lung metastases. This effect is associated with the recruitment of inflammatory cells to the lung and elevated levels of certain cytokines such as IL-6 in the lung airways. Antiinflammatory treatment prior to and after the biopsy reduces the development of metastases triggered by the biopsy. In addition, while lack of IL-6 does not affect primary tumor development, it protects from increasing number of metastases upon biopsy. Thus, our studies show that in addition to chronic inflammation, acute immune response caused by invasive procedures in the primary tumor may cause an increased risk on peripheral metastases, but the risk could be decreased by anti-inflammatory treatments.  相似文献   
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Introduction Lung cancer accounts for 20 % of cancer deaths in Spain. The most frequent subtype (87 %) is non-small cell lung cancer (NSCLC). Pemetrexed is a recently marketed drug added to NSCLC therapeutic arsenal. It seems to have become one of the most used options for the treatment of this condition over the last 3 years. Aim of the review To evaluate the efficacy and safety of pemetrexed in NSCLC, in the different therapy lines. Method A systematic search of published literature was conducted using the main databases (MEDLINE, EMBASE, the Cochrane Library and the Center for Reviews and Dissemination) and subsequently a search of referenced literature was performed. We included clinical trials, meta-analyses and systematic reviews. The evaluation of the quality of the articles was performed by pairs using specific assessment scales, Critical Appraisal Skills Program (CASP) adapted for CASP Spain. Then we extracted data on efficacy and safety according to the treatment line assessed. Results We identified 277 references. Finally, nine clinical trials and a meta-analysis complied with inclusion criteria. In first-line induction, treatment with pemetrexed associated with a platinum was similar in terms of efficacy to other alternative chemotherapy regimens, except in patients with non-squamous histology, in whom survival was higher in the experimental group. In maintenance treatment, greater efficacy was seen with pemetrexed in patients with non-squamous histology. In second-line treatment, there were no significant differences in terms of efficacy and safety for pemetrexed treatment versus other chemotherapy options. The most frequent adverse reactions were: hematological, gastrointestinal and neurological. All were significantly less frequent with pemetrexed versus other alternative therapies, except for liver toxicity. Conclusions Due to the high degree of uncertainty as to its efficacy in certain subgroups of patients, including conflicting data; to its recent incorporation, and therefore lack of safety data in the medium and long term, and the high budgetary impact of its incorporation into health systems, it seems reasonable to optimize its use, identifying those patients who may benefit most.  相似文献   
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To explore attitudes of physicians attending births in the public and private sectors and at the managerial level toward cesarean birth in Nicaragua. A qualitative study was conducted consisting of four focus groups with 17 physicians and nine in-depth interviews with decision-makers. Although study participants listed many advantages of vaginal birth and disadvantages of cesarean birth, they perceived that the increase in the cesarean birth rate in Nicaragua has resulted in a reduction in perinatal morbidity and mortality. They ascribed high cesarean birth rates to a web of interrelated provider, patient, and health system factors. They identified five actions that would facilitate a reduction in the number of unnecessary cesarean operations: establishing standards and protocols; preparing women and their families for labor and childbirth; incorporating cesarean birth rate monitoring and audit systems into quality assurance activities at the facility level; strengthening the movement to humanize birth; and promoting community-based interventions to educate women and families about the benefits of vaginal birth. Study participants believe that by performing cesarean operations they are providing the best quality of care feasible within their context. They do not perceive problems with their current practice. The identified causes of unnecessary cesarean operations in Nicaragua are multifactorial, so it appears that a multi-layered strategy is needed to safely reduce cesarean birth rates. The recent Nicaraguan Ministry of Health guidance to promote parto humanizado (“humanization of childbirth”) could serve as the basis for a collaborative effort among health care professionals, government, and consumer advocates to reduce the number of unnecessary cesarean births in Nicaragua.  相似文献   
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