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911.
Karolina Åberg Feng Dai Guangyun Sun Ember D. Keighley Subba R. Indugula Sarah T. Roberts Qi Zhang Diane Smelser Satupaitea Viali John Tuitele Li Jin Ranjan Deka Daniel E. Weeks Stephen T. McGarvey 《Obesity (Silver Spring, Md.)》2009,17(3):518-524
Obesity is a complex phenotype affected by genetic and environmental influences such as sociocultural factors and individual behaviors. Previously, we performed two separate genome‐wide investigations for adiposity‐related traits (BMI, percentage body fat (%BF), abdominal circumference (ABDCIR), and serum leptin and serum adiponectin levels) in families from American Samoa and in families from Samoa. The two polities have a common evolutionary history but have lately been influenced by variations in economic development, leading to differences in income and wealth and in dietary and physical activity patterns. We now present a genome‐wide linkage scan of the combined samples from the two polities. We adjust for environmental covariates, including polity of residence, education, cigarette smoking, and farm work, and use variance component methods to calculate univariate and bivariate multipoint lod scores. We identified a region on 9p22 with genome‐wide significant linkage for the bivariate phenotypes ABDCIR–%BF (1‐d.f. lod 3.30) and BMI–%BF (1‐d.f. lod 3.31) and two regions with genome‐wide suggestive linkage on 8p12 and 16q23 for adiponectin (lod 2.74) and the bivariate phenotype leptin‐ABDCIR (1‐d.f. lod 3.17), respectively. These three regions have previously been reported to be linked to adiposity‐related phenotypes in independent studies. However, the differences in results between this study and our previous polity‐specific studies suggest that environmental effects are of different importance in the samples. These results strongly encourage further genetic studies of adiposity‐related phenotypes where extended sets of carefully measured environmental factors are taken into account. 相似文献
912.
Summary A new technique is described which produces spiralization of human metaphase chromosomes. The important feature is heat followed by trypsin treatment. By varying conditions, it is possible to produce bands, spirals and intermediate stages. This provides a new approach to the understanding of banding and chromosome structure. 相似文献
913.
7 varieties of mustards were cultivated in statistically designed field during 1988 through 1989 and 1989 through 1990 crops in order to ascertain the resistant or less susceptible varieties for aflatoxin elaboration. Under field condition, none of the varieties of mustard was found to be resistant. Maximum aflatoxin contamination was observed in the late planting time (15 th November) crops. Insect (Lipaphis erysime) incidence had significant negative correlation (r=?0.9354) with the yield (Q/hectare) while it had significant positive correlation (r=0.5705) with aflatoxin contamination. 相似文献
914.
Antisense Downregulation of ς32 as a Transient Metabolic Controller in Escherichia coli: Effects on Yield of Active Organophosphorus Hydrolase 下载免费PDF全文
Ranjan Srivastava Hyung Joon Cha Marvin S. Peterson William E. Bentley 《Applied microbiology》2000,66(10):4366-4371
Plasmids containing an antisense fragment of the ς32 gene were constructed and introduced into Escherichia coli cells. Downregulation of the ς32-mediated stress response was evaluated under heat shock and ethanol stress and during the production of organophosphorus hydrolase (OPH). Northern blot analyses revealed that ς32 sense mRNA was virtually undetected in antisense-producing cultures from 5 to 20 min after antisense induction. However, lower-molecular-weight bands were found, presumably due to partial degradation of ς32 mRNA. While a >10-fold increase in ς32 protein level was found under ethanol stress in the control cultures, antisense producing cultures resulted in a <3-fold increase, indicating downregulation of ς32. Correspondingly, antisense synthesis resulted in a decreased level of a ς32 regulated chaperone (GroEL) for the first 2 h after induction relative to control cultures without ς32 antisense mRNA. The total yield of OPH in the presence of ς32 antisense was, on average, 62% of the yield without antisense. However, during ς32 antisense production, a sixfold-higher specific OPH activity was observed compared to non-antisense-producing cultures. 相似文献
915.
916.
Pyridine and other coal tar constituents as free radical-generating environmental neurotoxicants 总被引:3,自引:0,他引:3
Summary We have tested the hypothesis that chronic exposure to the principal constituents of the aqueous fraction of coal tar extracts can lead to the in vivo formation of substances which may produce neurological damage as the result of free radical generation and lipid peroxidation, these may be involved in the etiology of some neurological disorders. Artificial mixtures of the aqueous fraction of coal tar extracts were given in low concentrations to pigmented mice in their drinking water over a 3-month period. This resulted in significant increases in lipid peroxidation in the striatum, cerebellum and liver of the mice under test, the rank order being striatum > cerebellum > liver. These results are compatible with the possibility that coal tar emissions (as would be recovered or liberated in the burning, refining or beneficiation of coal) constitute a potential source of neurotoxicants with a predilection for damaging the nigrostriatal neuronal pathway. Our observations may thus have identified an important and hitherto unsuspected environmental source of neurotoxic chemicals, a possibility consistent with the proposed involvement of an environmental chemical factor in Parkinson's disease and perhaps in other neurological disorders. 相似文献
917.
We assessed the population status of endangered lion-tailed macaques (Macaca silenus) in the rain forests of Kudremukh Forest complex (Kudremukh National Park, Someshwara Wildlife Sanctuary and Mookambika Wildlife
Sanctuary), Western Ghats, Karnataka in January 2007. We performed a census of 20 groups in Kudremukh NP, 4 groups in Someshwara
WS, and 6 groups in Mookambika WS. We estimated the population size as ca. 451 individuals in the 3 parks. The forests of Kudremukh NP and Someshwara WS are continuous, and the present finding of
24 groups in a single continuous forest confirms the existence of another significant population of lion-tailed macaques. 相似文献
918.
Ranjan Kalita William Flanagan Jonathan Lightley Sunil Kumar Yuriy Alexandrov Edwin Garcia Mark Hintze Michalis Barkoulas Chris Dunsby Paul M. W. French 《Journal of biophotonics》2021,14(12):e202100144
We present a robust, low-cost single-shot implementation of differential phase microscopy utilising a polarisation-sensitive camera to simultaneously acquire four images from which phase contrast images can be calculated. This polarisation-resolved differential phase contrast (pDPC) microscopy technique can be easily integrated with fluorescence microscopy. 相似文献