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521.
Objective: Our goal was to assess the awakening cortisol response (ACR) in obese and reduced obese men and women. Research Methods and Procedures: Fifty‐one men (16 lean, 19 abdominally obese, and 16 reduced obese) and 31 women (12 lean, 10 subcutaneously obese, and 9 reduced obese) were selected to participate to this study. Strict ranges of BMI and waist circumference were used to select the participants. Medical examination, psychological assessment, anthropometric measurements, and blood sampling were undergone at the laboratory. Cortisol response to awakening was determined with saliva cortisol sampling being taken immediately at the time of awakening and 30 minutes thereafter over 3 days within a period of 2 months. Results: Men with visceral obesity exhibited an enhanced ACR, whereas this response tends to return to normal in a reduced obese state. In women, peripheral fat accumulation does not modify ACR, but weight loss increased the response. Discussion: These results highlight gender effects on ACR of obese and reduced obese subjects, which could be accounted for by the different fat distribution profiles that characterize men and women. They also provide further support for the usefulness of ACR in assessing the hypothalamic‐pituitary‐adrenal axis activity status.  相似文献   
522.

Background  

Fatigue is one of the most commonly reported and debilitating symptoms of multiple sclerosis (MS); approximately two-thirds of people with MS consider it to be one of their three most troubling symptoms. It may limit or prevent participation in everyday activities, work, leisure, and social pursuits, reduce psychological well-being and is one of the key precipitants of early retirement. Energy effectiveness approaches have been shown to be effective in reducing MS-fatigue, increasing self-efficacy and improving quality of life. Cognitive behavioural approaches have been found to be effective for managing fatigue in other conditions, such as chronic fatigue syndrome, and more recently, in MS. The aim of this pragmatic trial is to evaluate the clinical and cost-effectiveness of a recently developed group-based fatigue management intervention (that blends cognitive behavioural and energy effectiveness approaches) compared with current local practice.  相似文献   
523.
The molecular biology of leaf senescence   总被引:56,自引:2,他引:56  
Senescence is a complex, highly regulated, developmental phasein the life of a leaf that results in the co-ordinated degradationof macromolecules and the subsequent mobilization of componentsto other parts of the plant. The application of molecular biologytechniques to the study of leaf senescence has, in the lastfew years, enabled the isolation and characterization of a largerange of cDNA clones representing genes that show increasedexpression in senescing leaves. The analysis of these genesand identification of the function of the encoded proteins willallow a picture of the complex processes that take place duringsenescence to be assembled. To date, genes encoding degradativeenzymes such as proteases and nucleases, enzymes involved inlipid and carbohydrate metabolism and enzymes involved in nitrogenmobilization have all been identified as senescence-enhancedgenes. A variety of other genes of no obvious senescence-relatedfunction have also been identified; their role in senescencemay be less predictable and, possibly, more interesting. The combined action of several internal and external signalsmay be involved in the induction of senescence. Analysis ofthe regulatory mechanisms controlling the expression of senescence-inducedgenes will allow the signalling pathways that are involved inthe regulation of senescence to be elucidated. Experiments withtransgenic plants and mutants are already shedding light onthe role played by cytokinins and ethylene in regulating senescencein leaves. Key words: Senescence, cDNA clones, gene expression, signals  相似文献   
524.

Background  

Uncovering complex network structures from a biological system is one of the main topic in system biology. The network structures can be inferred by the dynamical Bayesian network or Granger causality, but neither techniques have seriously taken into account the impact of environmental inputs.  相似文献   
525.
Abstract We examined the serum requirements for surface phagocytosis of Staphylococcus epidermidis and Eschericia coli and for the subsequent chemiluminescent response of human neutrophils. Substantial surface phagocytosis of S. epidermidis occured in the absence of opsonins, although the presence of 10% pooled or heat-inactivated serum significantly increased phagocytosis. There was no significant difference between these opsonins, indicating that surface phagocytosis of S. epidermidis did not require complement, Unopsonized E. coli were not as readily phagocytized as S. epidermidis (33% versus 57%). In contrast to S. epidermidis optimal phagocytosis of E. coli required complement as 10% heat inactivated donor serum (HHS) was significantly less effective as an opsonin than 10% pooled healthy donor serum (PHS). The time kinetics for phagocytosis of each organism were similar, with most of the phagocytosis iluminescent response of neutrophils produced discrepant results. Maximal chemiluminescence was observed when neutrophils were stimulated with bacteria opsonized in PHS. The response to HHS-opsonized bacteria was less, and chemiluminescence to unopsonized bacteria was only marginally higher than the control, even though there was relatively good phagocytosis. These results define the opsonic requirements for surface phagocytosis of S. epidermidis and E. coli and indicate that although complement may not be required for phagocytosis, it is necessary for generation of a maximal oxidative burst, and thus may be essential for efficient intracellular killing.  相似文献   
526.
We have isolated sequences belonging to Tyl-copia group retrotransposons from the genomes of an amphibian (Pyxicephalus adspersa) and three reptiles (Conolophus subscristatus, Amblyrynchus cristatus and Pytas mucosus). Two different seqences were found in the amphibian (Tpa1 and Tpa2). Each is present in several copies per genome and absent from the genomes of two other amphibian species. The C. subcristatus sequence Tcs1 is present in multiple copies in both its host genome (Galapagos land iguana) and the genome of the related Galapagos marine iguana (A. cristatus). There is little or no polymorphism in Tcs1 insertions between different individual animals, suggesting that this sequence is not transposing rapidly in either iguana genome. The P. mucosus sequence Tpm1 shows a discontinuous distribution in snake species, suggesting that it has either been lost from many lineages during vertical germline transmission or has been transferred horizontally in some snake species. Phylogenetic comparisons of all these sequences with each other and with other members of this retrotransposon group from other animals and plants show that sequences within a particular vertebrate species are most closely related to each other, consistent with a vertical transmission model for their evolution.  相似文献   
527.
ObjectiveTo determine whether people whose marital partners have depression, diabetes, hypertension, ischaemic heart disease, stroke, hyperlipidaemia, peptic ulcer disease, or asthma or chronic obstructive pulmonary disease are at increased risk of the same disease.DesignCross sectional study.Setting10 practices from the Trent Focus Collaborative Research Practice Network.Participants8386 married couples (16 772 individuals) from a population of 29 014 participants aged 30-74 years.OutcomesRisk of disease in participants whose marital partner had that disease compared with those whose partner did not.ResultsAfter both partners'' age, smoking, and obesity and which general practice they attend were adjusted for, participants whose marital partner had asthma, depression, hypertension, hyperlipidaemia, and peptic ulcer disease were at increased risk of having the same disease. The adjusted odds ratios were 1.69 (95% confidence interval 1.43 to 2.98) for asthma, 2.08 (1.71 to 2.54) for depression, 1.32 (1.04 to 1.67) for hypertension, 1.44 (1.19 to 1.75) for hyperlipidaemia, and 2.01 (1.48 to 2.73) for peptic ulcer disease.ConclusionPartners of people with specific diseases are at increased risk of the disease themselves—at least 70% increased risk for asthma, depression, and peptic ulcer disease. This implicates shared environmental causes in some diseases in addition to any genetic or distant exposure or shared behaviours with respect to seeking health care.

What is already known on this topic

People whose spouses have hypertension are at increased risk of hypertensionLittle is known about the risks of disease for spouses of patients with diseases other than hypertension

What this study adds

People whose marital partner had asthma, depression, and peptic ulcer disease were at increased risk of having the same diseaseShared environmental factors contribute to the risk of diseasesThe costs and benefits of screening people for diseases of their spouses needs to be considered  相似文献   
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