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121.
Objective: The relationship between body mass index (BMI: kg/m2) and personality seems to differ for men and women, although these effects may be driven by the extremes of the BMI distribution. It is unclear whether these associations exist for most individuals in the relatively normal range of BMI scores, excluding the thinnest and heaviest extremes in the population. We tested the association of BMI with neuroticism, extraversion, and psychoticism with a trimmed BMI sample. Research Methods and Procedures: Using a cross‐sectional design, we tested the association of BMI with the aforementioned psychological variables in a British population‐based sample. Participants were 7889 adult men and women (30 to 50 years old) selectively sampled from four counties in west England. Participants reported their height and weight and completed the Eysenck Personality Inventory (EPQ). We tested the association of BMI with the EPQ subscales among individuals with BMI ≥19.16 kg/m2 and ≤37.78 kg/m2, i.e., the approximate 5th and 95th percentiles. Results: Despite elimination of extreme BMIs, different associations between BMI and EPQ subscales emerged for men and women. Among women, increasing BMI was significantly associated with increased neuroticism and reduced extraversion. Among men, increasing BMI was associated with increased extraversion and psychoticism. In all cases, the magnitude of the association was very small. Discussion: Increasing BMI was associated with potentially poorer adjustment among women but better adjustment among men. These findings are consistent with recent reports and, taken together, suggest that these patterns are not accounted for solely by the extremes of the BMI distribution.  相似文献   
122.
Recent research from the site of Pella in Jordan examines the process and timing of olive cultivation. The frequent presence of olive remains from the Pottery Neolithic, beginning in the Yarmoukian, suggests that exploitation of the olive dates from as early as c. 6200 cal bce, with evidence of oil pressing from at least c. 5200 cal bce. Morphometric data, spanning the Late Neolithic to the Middle Iron Age II, using the measurement of olive endocarp length and width, demonstrates a reduction in the size variation of olive endocarps through time, in addition to an increase in their length, likely the result of selection pressure on trees. At Pella, this change occurs sometime after the Chalcolithic and before the Late Bronze Age, probably post-dating the earliest phases of the Early Bronze Age. Domestication is thus later than Teleilat Ghassul (Jordan), which has the earliest morphological evidence for olive domestication, and suggests that olive domestication was a regionally and temporally diverse process.  相似文献   
123.
Parental feeding styles may promote overeating or overweight in children. A comprehensive literature review was undertaken to summarize the associations between parental feeding styles and child eating and weight status. Twenty‐two studies were identified. We systematically coded study attributes and outcomes and tested for patterns of association. Nineteen studies (86%) reported at least one significant association between parental feeding style and child outcome, although study methodology and results varied considerably. Studies measuring parental feeding restriction, as opposed to general feeding control or another feeding domain, were more likely to report positive associations with child eating and weight status. Certain associations differed by gender and by outcome measurement (e.g., rate of eating as opposed to total energy intake). Parental feeding restriction, but no other feeding domain, was associated with increased child eating and weight status. Longitudinal studies are needed to test underlying causal pathways, including bidirectional causal models, and to substantiate findings in the presence of other obesity risk factors.  相似文献   
124.
Transgenic creeping bentgrass with delayed dollar spot symptoms   总被引:7,自引:0,他引:7  
Creeping bentgrass (Agrostis palustris Huds) is animportant turfgrass used on golf course greens and fairways. It is susceptibleto a number of fungal pathogens and requires considerable fungicide use fordisease control. Transgenic approaches may be useful in improving the level ofdisease resistance. We have generated transgenic creeping bentgrass plantsexpressing PR5K from Arabidopsis thaliana (L.) Henyh. PR5Kis a receptor protein kinase whose extracellular domain is homologous to thePR5family of pathogenesis-related proteins. In a field test of plants inoculatedwith the fungal pathogen dollar spot (Sclerotiniahomoeocarpa F.T. Bennett) four of the eight transgenic lines showeddelays in disease expression of 29 to 45 days, relative to the control plants.  相似文献   
125.
Multiple lines of evidence have implicated the short arm of chromosome 8 as harboring genes important in prostate carcinogenesis. Although most of this evidence comes from the identification of frequent somatic alterations of 8p loci in prostate cancer cells (e.g., loss of heterozygosity), studies have also suggested a role for 8p genes in mediation of inherited susceptibility to prostate cancer. To further examine this latter possibility, we performed linkage analyses, in 159 pedigrees affected by hereditary prostate cancer (HPC), using 24 markers on the short arm of chromosome 8. In the complete set of families, evidence for prostate cancer linkage was found at 8p22-23, with a peak HLOD of 1.84 (P=.004), and an estimate of the proportion of families linked (alpha) of 0.14, at D8S1130. In the 79 families with average age at diagnosis >65 years, an allele-sharing LOD score of 2.64 (P=.0005) was observed, and six markers spanning a distance of 10 cM had LOD scores >2.0. Interestingly, the small number of Ashkenazi Jewish pedigrees (n=11) analyzed in this study contributed disproportionately to this linkage. Mutation screening in HPC probands and association analyses in case subjects (a group that includes HPC probands and unrelated case subjects) and unaffected control subjects were carried out for the putative prostate cancer-susceptibility gene, PG1, previously localized to the 8p22-23 region. No statistical differences in the allele, genotype, or haplotype frequencies of the SNPs or other sequence variants in the PG1 gene were observed between case and control subjects. However, case subjects demonstrated a trend toward higher homozygous rates of less-frequent alleles in all three PG1 SNPs, and overtransmission of a PG1 variant to case subjects was observed. In summary, these results provide evidence for the existence of a prostate cancer-susceptibility gene at 8p22-23. Evaluation of the PG1 gene and other candidate genes in this area appears warranted.  相似文献   
126.
BARTLETT, SUSAN J., MYLES S. FAITH, KEVIN R. FONTAINE, LAWRENCE J. CHESKIN, AND DAVID B. ALLISON. Is the prevalence of successful weight loss and maintenance higher in the general community than the research clinic? Obes Res. Objective: The prevalence of successful weight loss remains unclear. In 1982, Schachter concluded that in the general population, the rate of “self-cured” obesity approached 63%–much higher than the rate from clinical trials. Several subsequent studies have addressed this issue. Research Methods and Procedures: Our initial goal was to meta-analyze these studies to evaluate the validity of the original hypotheses and the extent to which additional investigations supported the findings. We began by restating Schachter's hypotheses in precise, testable terms. Results: A systematic review of these studies found many methodological limitations and much heterogeneity among the samples studied, hypotheses addressed, and operational definitions. Some of these limitations appear to stem from the lack of clear, precise statements of the exact hypotheses tested. Differences among studies are delineated, and we outline why meta-analytic pooling of these data appears inappropriate. Conclusions: The current data are inadequate to draw any definite conclusions regarding the cure rate of obesity. Criteria for the adequate study of success rates with “self-cure” in the general population are proposed.  相似文献   
127.
Gland cells of the gastrodermis of Hydra when isolated from the epidermis are capable of dedifferentiating into interstitial cells. Under proper environmental conditions these interstitial cells are capable of undergoing meiotic divisions and forming normal gametes. This dedifferentiation and redifferentiation sequence has been studied at the level of the light and electron microscope. It is concluded that in Hydra there is no specific germinal cell line determined during embryogeny, and that a somatic cell under proper environmental conditions can be induced to undergo meiosis.  相似文献   
128.
Melanocortin-4 receptor (MC4R) is a G-protein-coupled receptor expressed in the hypothalamus where it controls feeding behavior. MC4R cycles constitutively and is internalized at the same rate in the presence or absence of stimulation by the agonist, melanocyte-stimulating hormone (α-MSH). This is different from other G-protein-coupled receptors, such as β(2)-adrenergic receptor (β(2)AR), which internalizes more rapidly in response to agonist stimulation. Here, it is found that in immortalized neuronal Neuro2A cells expressing exogenous receptors, constitutive endocytosis of MC4R and agonist-dependent internalization of β(2)AR were equally sensitive to clathrin depletion. Inhibition of MC4R endocytosis by clathrin depletion decreased the number of receptors at the cell surface that were responsive to the agonist, α-MSH, by 75%. Mild membrane cholesterol depletion also inhibited constitutive endocytosis of MC4R by ~5-fold, while not affecting recycling of MC4R or agonist-dependent internalization of β(2)AR. Reduced cholesterol did not change the MC4R dose-response curve to α-MSH, but it decreased the amount of cAMP generated per receptor number indicating that a population of MC4R at the cell surface becomes nonfunctional. The loss of MC4R function increased over time (25-50%) and was partially reversed by mutations at putative phosphorylation sites (T312A and S329A). This was reproduced in hypothalamic GT1-7 cells expressing endogenous MC4R. The data indicate that constitutive endocytosis of MC4R is clathrin- and cholesterol-dependent. MC4R endocytosis is required to maintain MC4R responsiveness to α-MSH by constantly eliminating from the plasma membrane a pool of receptors modified at Thr-312 and Ser-329 that have to be cycled to the endosomal compartment to regain function.  相似文献   
129.
Tangential (crossflow) filtration of a plasma/serum mixture through 0.2 micrometer-poresize polycarbonate track-etch membrane filters (PC) at pressures less than 10 psi removes low density lipoproteins (LDL) and very low density lipoproteins (VLDL) but not high density lipoproteins (HDL) from the filtrate. At pressures greater than 10 psi all lipoproteins pass through the PC. Once the filters have been intruded with LDL and VLDL those lipoproteins continue to pass the filters despite subsequent reduction in differential pressure below 10 psi.  相似文献   
130.
The pulsed-field technique of clamped homogeneous electric field electrophoresis was employed to characterize and size genomic DNA of three pediocin-producing (Ped+) and two non-pediocin-producing (Ped-) strains of Pediococcus acidilactici. Comparison of genomic fingerprints obtained by digestion with the low-frequency-cleavage endonuclease AscI revealed identical restriction profiles for four of the five strains analyzed. Summation of results for 10 individually sized AscI fragments estimated the genome length to be 1,861 kb for the four strains (H, PAC1.0, PO2, and JBL1350) with identical fingerprints. Genomic analysis of the pediocin-sensitive, plasmid-free strain P. acidilactici LB42 with the unique fingerprint revealed nine AscI fragments and a genome length of about 2,133 kb. Ped- (JBL1350) and Ped+ (JBL1095) starter cultures (one each) were used to separately prepare turkey summer sausage coinoculated with a four-strain Listeria monocytogenes mixture (ca. 10(5) CFU/g). The starter cultures produced equivalent amounts of acid during fermentation, but counts of L. monocytogenes were reduced to a greater extent in the presence of the Ped+ starter culture (3.4 log10 unit decrease) than in the presence of the Ped- starter culture (0.9 log10 unit decrease). Although no listeriae were recovered from sausages following the cook/shower, appreciable pediocin activity was recovered from sausages prepared with the Ped+ strain for at least 60 days during storage at 4 degrees C. The results of this study revealed genomic similarities among pediococcal starter cultures and established that pediocins produced during fermentation provide an additional measure of safety against listerial proliferation in turkey summer sausage.  相似文献   
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