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排序方式: 共有187条查询结果,搜索用时 156 毫秒
91.
92.
Giovana C. Freitas Rodrigo O. Saga Kitamura João Henrique G. Lago Maria Claudia M. Young Elsie F. Guimarães Massuo J. Kato 《Phytochemistry letters》2009,2(3):119-122
The CH2Cl2 and MeOH extracts from leaves of Piper caldense were subjected to chromatographic separation procedures to afford the new prenylated benzoic acid, caldensinic acid (3-[(2′E,6′E,10′E)-11′-carboxy-3′,7′,15′-trimethylhexadeca-2′,6′,10′,14′-tetraenyl]-4,5-dihydroxybenzoic acid) whose structure was determined by spectral analysis, mainly NMR (1H, 13C, HSQC, HMBC) and ESI-MS. The natural compound and derivatives displayed antifungal activity against the phytopathogenic fungi Cladosporium cladosporioides and C. sphaerospermum by direct bioautography. 相似文献
93.
Emily Oken Susanna Y. Huh Elsie M. Taveras Janet W. Rich‐Edwards Matthew W. Gillman 《Obesity (Silver Spring, Md.)》2005,13(11):2021-2028
Objective: To examine the extent to which maternal prenatal smoking is associated with adiposity, central adiposity, and blood pressure in 3‐year‐old children. Research Methods and Procedures: We studied 746 mother‐child pairs in Project Viva, a prospective cohort study, and categorized mothers as never, early pregnancy, or former smokers. Main outcome measures were overweight (BMI for age and sex > 85th percentile), BMI z‐score, sum of subscapular (SS) and triceps (TR) skinfolds, SS:TR skinfold ratio, and systolic blood pressure (SBP). Results: One hundred sixty‐one (22%) mothers quit smoking before pregnancy, 71 (10%) smoked in early pregnancy, and 514 (69%) never smoked. At age 3 years, 204 (27%) children were overweight. On multivariable analysis, compared with children of never smokers, children of early pregnancy smokers had an elevated risk for overweight [odds ratio (OR), 2.2; 95% confidence interval (CI), 1.2, 3.9] and higher BMI z‐score (0.30 units; 95% CI, 0.05, 0.55), SS + TR (2.0 mm; 95% CI, 0.9, 3.0), and SBP (2.4 mm Hg; 95% CI, ?0.1, 4.9). Children of former smokers were not more overweight (BMI z‐score, 0.02 units; 95% CI, ?0.15, 0.19) but had higher SBP (1.5 mm Hg; 95% CI, ?0.1, 3.2). We saw no relationship of smoking with central adiposity (SS:TR). Discussion: Former and early pregnancy smokers had children with somewhat higher SBP, but only early pregnancy smokers had children who were more overweight. Mechanisms linking smoking with child adiposity and blood pressure may differ. A long‐term impact of maternal smoking on offspring cardiovascular risk provides further reason to reduce smoking in women. 相似文献
94.
Clinical effectiveness of the Massachusetts Childhood Obesity Research Demonstration initiative among low‐income children
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95.
BMI z‐Scores are a poor indicator of adiposity among 2‐ to 19‐year‐olds with very high BMIs,NHANES 1999‐2000 to 2013‐2014
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96.
Andrade EH Carreira LM da Silva MH da Silva JD Bastos CN Sousa PJ Guimarães EF Maia JG 《化学与生物多样性》2008,5(1):197-208
This paper contains data on the chemical composition of the essential oils of 22 leaf samples of Piper marginatum Jacq. collected in different areas and ecosystems of the brazilian Amazon, as well as an overview of the available literature. The species presents a large synonymy based on their different leaf characteristics and distinct scents where some of them smell like anise or very close compounds. By GC, GC/MS, and cluster analysis, we identified seven chemotypes for the leaf oils. The main components found in chemotype I were safrole (1) and 3,4-(methylenedioxy)propiophenone (2). The chemotype II was dominated by 3,4-(methylenedioxy)propiophenone (2) and p-mentha-1(7),8-diene (10). The major compounds identified in chemotype III were 3,4-(methylenedioxy)propiophenone (2), myristicin (3), (E)-beta-ocimene (11), and gamma-terpinene (12). In the chemotype IV, the principal constituents were beta-caryophyllene (13), alpha-copaene (14), and 3,4-(methylenedioxy)propiophenone (2). The chemotype V was dominated by (E)-isoosmorhizole (6), (E)-anethole (8), and isoosmorhizole (7). The main compounds found in the chemotype VI were 2-methoxy-4,5-(methylenedioxy)propiophenone (4), methoxy-4,5-(methylenedioxy)propiophenone isomer 5, and (E)-isoosmorhizole (6). The major constituents in chemotype VII were beta-caryophyllene (13), bicyclogermacrene (15), and (E)-asarone (9). 相似文献
97.
Objective: To examine parental perceptions of primary care efforts aimed at childhood obesity prevention Methods and Procedures: We interviewed 446 parents of children, aged 2–12 years, with an age‐ and sex‐specific BMI ≥85th percentile; interviews occurred within 2 weeks of their child's primary care visit. We assessed parental ratings of the nutrition and physical activity advice received. Using children's clinical heights and weights and parents' self‐reported heights and weights, we classified children into three categories: BMI 85th–94th percentile without an overweight parent, BMI 85th–94th percentile with an overweight parent (adult BMI ≥25 kg/m2), and BMI ≥95th percentile. Results: In multivariate analyses, compared to parents of children with BMI ≥95th percentile, overweight parents with children whose BMI was 85th–94th percentile were more likely to report receiving too little advice on nutrition and physical activity (odds ratio (OR) 3.05; 95% confidence interval (CI) 1.49, 6.25) and to rate as poor or fair the quality of advice they received (OR 2.23; 95% CI 1.18, 4.24). Independently, African‐American (OR 2.55; 95% CI 1.18, 5.51) and Hispanic/Latino (OR 2.78; 95% CI 1.27, 6.10) parents were more likely than white parents to rate as poor or fair the quality of advice they received. Discussion: Parental overweight is associated with low subjective ratings of overweight counseling in pediatric primary care. Our findings of poorer perceived quality among racial/ethnic minority parents need further investigation. 相似文献
98.
Rodrigues CO Nerlick ST White EL Cleveland JL King ML 《Development (Cambridge, England)》2008,135(11):1903-1911
Myc-deficient mice fail to develop normal vascular networks and Myc-deficient embryonic stem cells fail to provoke a tumor angiogenic response when injected into immune compromised mice. However, the molecular underpinnings of these defects are poorly understood. To assess whether Myc indeed contributes to embryonic vasculogenesis we evaluated Myc function in Xenopus laevis embryogenesis. Here, we report that Xc-Myc is required for the normal assembly of endothelial cells into patent vessels during both angiogenesis and lymphangiogenesis. Accordingly, the specific knockdown of Xc-Myc provokes massive embryonic edema and hemorrhage. Conversely, Xc-Myc overexpression triggers the formation of ectopic vascular beds in embryos. Myc is required for normal expression of Slug/Snail2 and Twist, and either XSlug/Snail2 or XTwist could compensate for defects manifest by Xc-Myc knockdown. Importantly, knockdown of Xc-Myc, XSlug/Snail2 or XTwist within the lateral plate mesoderm, but not the neural crest, provoked embryonic edema and hemorrhage. Collectively, these findings support a model in which Myc, Twist and Slug/Snail2 function in a regulatory circuit within lateral plate mesoderm that directs normal vessel formation in both the vascular and lymphatic systems. 相似文献
99.
100.
Nostoc punctiforme is a phenotypically complex, filamentous, nitrogen-fixing cyanobacterium, whose vegetative cells can mature in four developmental directions. The particular developmental direction is determined by environmental signals. The vegetative cell cycle is maintained when nutrients are sufficient. Limitation for combined nitrogen induces the terminal differentiation of heterocysts, cells specialized for nitrogen fixation in an oxic environment. A number of unique regulatory events and genes have been identified and integrated into a working model of heterocyst differentiation. Phosphate limitation induces the transient differentiation of akinetes, spore-like cells resistant to cold and desiccation. A variety of environmental changes, both positive and negative for growth, induce the transient differentiation of hormogonia, motile filaments that function in dispersal. Initiation of the differentiation of heterocysts, akinetes and hormogonia are hypothesized to depart from the vegetative cell cycle, following separate and distinct events. N. punctiforme also forms nitrogen-fixing symbiotic associations; its plant partners influence the differentiation and behavior of hormogonia and heterocysts. N. punctiforme is genetically tractable and its genome sequence is nearly complete. Thus, the regulatory circuits of three cellular differentiation events and symbiotic interactions of N. punctiforme can be experimentally analyzed by functional genomics. 相似文献