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The purpose of our study was to determine the prevalence of protein-calorie malnutrition (PCM), ocular diseases, and vitamin A deficiency in preschool children selected at random in a rural zone of the groundnut belt of Senegal. The prevalence of PCM was 37.1% (95% CI 33.8-40.2%) according to the Waterlow classification, with a majority of stunting, and prevalence of hypovitaminosis A was estimated to be 11.4% (95% CI 9.3-13.5%) by using impression cytology. Furthermore, 19.4% (95% CI 15.8-22.0%) of the children might be defined at risk of deficiency. The prevalence of Bitot's spots was equal to 0.2% (95% CI 0.03-0.9%). A problem of PCM associated with a health-endangering vitamin A deficiency existed.  相似文献   
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OBJECTIVE: We hypothesised that backward disequilibrium (BD), defined by a posterior position of the centre of mass with respect to the base of support, could be caused by a backward tilt in the perception of verticality. METHODS: The relationship between BD, the perception of verticality, and the history of falls in 25 subjects aged 84.5+/-7.4 years was analysed. An original ordinal scale, the BD scale (BDS), was used to quantify BD. Postural (PV) and haptic verticals (HV) were measured in sagittal plane. RESULTS: BDS scores closely correlated with the number of falls (r = 0.81, p =10(-5)). The more the PV was tilted backward, the greater the BDS scores (r = -0.95, p<10(-6)), with a huge backward tilt of about 15 degrees in 4 subjects with severe BD. In these subjects, the tilt in perception of verticality was transmodal since a severe backward HV tilt was also found. CONCLUSIONS: This transmodality suggested high-order cognitive disruption in the construction of the subjective vertical used in postural control by subjects showing BD, which confirmed our hypothesis. SIGNIFICANCE: This study clearly shows that perception and action with respect to gravity are closely related and brings a new insight about fall mechanisms in the elderly.  相似文献   
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Plant microtubules are organized into specific cell cycle-dependent arrays that have been implicated in diverse cellular processes, including cell division and organized cell expansion. Mutations in four Arabidopsis genes collectively called the PILZ group result in lethal embryos that consist of one or a few grossly enlarged cells. The mutant embryos lack microtubules but not actin filaments. Whereas the cytokinesis-specific syntaxin KNOLLE is not localized properly, trafficking of the putative auxin efflux carrier PIN1 to the plasma membrane is normal. The four PILZ group genes were isolated by map-based cloning and are shown to encode orthologs of mammalian tubulin-folding cofactors (TFCs) C, D, and E, and associated small G-protein Arl2 that mediate the formation of alpha/beta-tubulin heterodimers in vitro. The TFC C ortholog, PORCINO, was detected in cytosolic protein complexes and did not colocalize with microtubules. Another gene with a related, although weaker, embryo-lethal phenotype, KIESEL, was shown to encode a TFC A ortholog. Our genetic ablation of microtubules shows their requirement in cell division and vesicle trafficking during cytokinesis, whereas cell growth is mediated by microtubule-independent vesicle trafficking to the plasma membrane during interphase.  相似文献   
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High circulating concentration of insulin-like growth factor-I (IGF-I) and low circulating concentration of IGF binding protein-3 (IGFBP-3) have been associated with increased risk for breast, prostate, and colorectal cancers. Building on previous work in the Multiethnic Cohort (MEC) showing significant differences in IGF-I levels across racial/ethnic groups, we investigated which lifestyle and dietary factors are associated with levels of IGF-I and IGFBP-3 in a random sample of 1,000 MEC participants, which included Native Hawaiian, African American, Japanese, Latino, and White men and women. Crude analyses confirmed the existence of differences in protein levels with race/ethnicity, sex, age, and body size. Reproductive, physical activity, smoking, and diet variables had less consistent effects. In multivariate analyses, IGF-I levels were lower and IGFBP-3 were higher in females versus males. IGF-I and IGFBP-3 declined with increasing age in both genders. Women in the highest quartile of body mass index showed depressed IGF-I and IGFBP-3 levels; in men, height was significantly positively associated with both proteins. In women, alcohol was directly associated with IGFBP-3. Both proteins were lowest among female Latinos. IGF-I was highest among female African Americans. In men, IGFBP-3 was lowest among African Americans. Overall, although these factors were statistically significant determinants of IGF-related protein levels, they did not explain much of the variation in these levels. A positive correlation was found between IGF-I levels (ng/mL) and colon cancer incidence rates (per 100,000) within the MEC by race/ethnicity for both sexes but not for either breast or prostate cancer.  相似文献   
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FUNDAMENTAL IMPORTANCE OF POSTURE: In the elderly subject, preservation of posture is fundamental to maintaining functional independence. In recent years, there has been much progress in our understanding of the mechanisms underlying strategies used to control equilibrium in the upright position. Physiological aging, associated with diverse disease states, dangerously alters the postural function, particularly anticipated adjustments which allow an adaptation of posture to movement. CLINICAL ASSESSMENT OF POSTURE: Several tests have been developed to assess posture in the elderly subject, particularly the time it takes to start walking. We selected certain tests which can be used in everyday practice to predict falls: the stance test, the improved Romberg test, the "timed get up and go test", measurement of walking cadence, assessment of balance reactions, sitting-standing and standing-sitting movements and capacity to get up off the floor. PATIENT CARE: Elderly patients with equilibrium disorders can benefit from specific personalized rehabilitation protocols. Different techniques have been developed for multiple afferential stimulation, reprogramming postural strategies, and correcting for deficient motor automatisms.  相似文献   
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The survival of breast cancer patients is largely influenced by tumor characteristics, such as TNM stage, tumor grade and hormone receptor status. However, there is growing evidence that inherited genetic variation might affect the disease prognosis and response to treatment. Several lines of evidence suggest that alleles influencing breast cancer risk might also be associated with breast cancer survival. We examined the associations between 35 breast cancer susceptibility loci and the disease over‐all survival (OS) in 10,255 breast cancer patients from the National Cancer Institute Breast and Prostate Cancer Cohort Consortium (BPC3) of which 1,379 died, including 754 of breast cancer. We also conducted a meta‐analysis of almost 35,000 patients and 5,000 deaths, combining results from BPC3 and the Breast Cancer Association Consortium (BCAC) and performed in silico analyses of SNPs with significant associations. In BPC3, the C allele of LSP1‐rs3817198 was significantly associated with improved OS (HRper‐allele=0.70; 95% CI: 0.58–0.85; ptrend = 2.84 × 10?4; HRheterozygotes = 0.71; 95% CI: 0.55–0.92; HRhomozygotes = 0.48; 95% CI: 0.31–0.76; p2DF = 1.45 × 10?3). In silico, the C allele of LSP1‐rs3817198 was predicted to increase expression of the tumor suppressor cyclin‐dependent kinase inhibitor 1C (CDKN1C). In the meta‐analysis, TNRC9‐rs3803662 was significantly associated with increased death hazard (HRMETA =1.09; 95% CI: 1.04–1.15; ptrend = 6.6 × 10?4; HRheterozygotes = 0.96 95% CI: 0.90–1.03; HRhomozygotes = 1.21; 95% CI: 1.09–1.35; p2DF=1.25 × 10?4). In conclusion, we show that there is little overlap between the breast cancer risk single nucleotide polymorphisms (SNPs) identified so far and the SNPs associated with breast cancer prognosis, with the possible exceptions of LSP1‐rs3817198 and TNRC9‐rs3803662.  相似文献   
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To evaluate the roles of CYP1A1 polymorphisms [Ile 462Val and T 6235C (MspI)] and deletion of GSTM1 and GSTT1 in lung cancer development in Asian populations, a pooled analysis was conducted on 13 existing studies included in Genetic Susceptibility to Environmental Carcinogenesis database. This pooled analysis included 1,971 cases and 2,130 controls. Lung cancer risk was estimated as odds ratios (OR) and 95% confidence intervals (95% CI) using unconditional logistic regression model adjusting for age, sex, and pack-year. The CYP1A1 6235C variant was associated with squamous cell lung cancer (TC versus TT: OR, 1.42; 95% CI, 0.96-2.09; CC versus TT: OR, 1.97; 95% CI, 1.26-3.07; P trend = 0.003). In haplotype analysis, 462Val-6235T and Ile-C haplotypes were associated with lung cancer risk with reference to the Ile-T haplotype (OR, 3.41; 95% CI, 1.78-6.53 and OR, 1.39; 95% CI, 1.12-1.71, respectively). The GSTM1-null genotype increased squamous cell lung cancer risk (OR, 1.36; 95% CI, 1.05-1.77). When the interaction was evaluated with smoking, increasing trend of lung cancer risk as pack-year increased was stronger among those with the CYP1A1 6235 TC/CC genotype compared with those with TT genotype (P interaction = 0.001) and with the GSTM1-null genotype compared with the present type (Pinteraction = 0.08, when no genotype effect with no exposure was assumed). These results suggest that genetic polymorphisms in CYP1A1 and GSTM1 are associated with lung cancer risk in Asian populations. However, further investigation is warranted considering the relatively small sample size when subgroup analyses were done and the lack of environmental exposure data other than smoking.  相似文献   
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