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There is controversy about whether supplementing diets with marine fish oil can regress, promote or prevent atherosclerosis. Therefore the effects of an Atlantic pilchard oil (FO) supplement and dietary change were measured in a proven atherosclerosis model. Vervet or African Green monkeys were fed an atherogenic diet (AD) for long enough to ensure progression before treatments started. Matched groups were then treated for 20 months, either by adding FO to the AD (AD/FO), or by changing to a therapeutic diet with FO (TD/FO). Control treatments consisted of supplementing with sunflower oil (SO) instead of FO, so that treatments were AD/SO and TD/SO. The same total polyunsaturates were supplied by the FO and SO and the dose of FO was realistic (2.5% of total energy). A reference group (R) received the TD with no oil supplements. Supplementing with FO did not change the concentrations of total, low or high density lipoprotein cholesterol in plasma. After The AD/FO the intimas of aortas contained more total (p < or = 0.001), free (p < or = 0.05) and esterified (p < or = 0.05) cholesterol, total phospholipid (p < or = 0.01) and sphingomyelin (p < or = 0.05) than after the AD/SO. After FO supplementation eicosapentaenoic acid was significantly higher and arachidonic acid significantly lower in the plasma and aorta intima phosphatidylcholine. None of these changes was anti-atherogenic in terms of atherosclerosis measured in the same individuals (1). Nor did FO increase the efficacy of the TD.  相似文献   
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The diagnosis of respiratory chain deficiencies (RCDs) is complicated and the need for a diagnostic biomarker or biosignature has been widely expressed. In this study, the metabolic profile of a selected group of 29 RCD patients, with a predominantly muscle disease phenotype, and 22 controls were investigated using targeted and untargeted analyses of three sub-sections of the human metabolome, including urinary organic acids and amino acids [measured by gas chromatography–mass spectrometry (GC–MS)], as well as acylcarnitines (measured by electrospray ionization tandem MS). Although MS technologies are highly sensitive and selective, they are restrictive by being applied only to sub-sections of the metabolome; an untargeted nuclear magnetic resonance (NMR) spectroscopy approach was therefore also included. After data reduction and pre-treatment, a biosignature comprising six organic acids (lactic, succinic, 2-hydroxyglutaric, 3-hydroxyisobutyric, 3-hydroxyisovaleric and 3-hydroxy-3-methylglutaric acids), six amino acids (alanine, glycine, glutamic acid, serine, tyrosine and α-aminoadipic acid) and creatine, was constructed from uni- and multivariate statistical analyses and verified by cross-validation. The results presented here provide the first proof-of-concept that the metabolomics approach is capable of defining a biosignature for RCDs. We postulate that the composite of organic acids ≈ amino acids > creatine > betaine > carnitines represents the basic biosignature for RCDs. Validated through a prospective study, this could offer an improved ability to assign individual patients to a group with defined RCD characteristics and improve case selection for biopsy procedures, especially in infants and children.  相似文献   
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The evolution of altruism often requires genetic similarity among interactors. For structured populations in which a social trait affects all group members, this entails positive assortment, meaning that cooperators and noncooperators tend to be segregated into different groups. Several authors have claimed that mechanisms other than common descent can produce positive assortment, but this claim has not been generally accepted. Here, we describe one such mechanism. The process of "environmental feedback" requires only that the cooperative trait affects the quality of the local environment and that individuals are more likely to leave low-quality than high-quality environments. We illustrate this dynamic using an agent-based spatial model of feeding restraint. Depending on parameter settings, results included both positive assortment (required for the evolution of altruism) and negative assortment (required for the evolution of spite). The mechanism of environmental feedback appears to be a general one that could play a role in the evolution of many forms of cooperation.  相似文献   
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Drought is a major abiotic stress factor limiting rice production in rainfed areas. In this study we identified a large-effect quantitative trait locus (QTL) associated with grain yield under stress in five different populations on chromosome 1. The effect of this QTL was further confirmed and characterized in five backcross populations in a total of sixteen stress and non-stress trials during 2006 and 2008. In all the stress trials (eight in total) qDTY1.1 showed strong association with grain yield explaining on average 58% of the genetic variation in the trait. Homozygotes for the tolerant parent allele (Apo) yielded on average 27% more than the susceptible parent allele (IR64) homozygotes. Using an Apo/3*IR64 population, the peak of this QTL (qDTY1.1) was mapped to an interval between RM486 and RM472 at 162.8?cM at a LOD score of 9.26. qDTY1.1 was strongly associated with plant height in all the environments; this was probably due to the presence of the sd1 locus in this genomic region. In a Vandana/3*IR64 population segregating for sd1, a strong relation between plant height and yield under stress was observed. The observed relation between increased height and drought tolerance is likely due to tight linkage between qDTY1.1 and sd1 and not due to pleiotrophy of sd1. Thus there is a possibility of combining reduced plant height and drought tolerance in rice. The large and consistent effect of qDTY1.1 across several genetic backgrounds and environments makes it a potential strong candidate for use in molecular breeding of rice for drought tolerance.  相似文献   
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Background

Detection and quantification of hepatitis C virus (HCV) RNA is integral to diagnostic and therapeutic regimens. All molecular assays target the viral 5′-noncoding region (5′-NCR), and all show genotype-dependent variation of sensitivities and viral load results. Non-western HCV genotypes have been under-represented in evaluation studies. An alternative diagnostic target region within the HCV genome could facilitate a new generation of assays.

Methods and Findings

In this study we determined by de novo sequencing that the 3′-X-tail element, characterized significantly later than the rest of the genome, is highly conserved across genotypes. To prove its clinical utility as a molecular diagnostic target, a prototype qualitative and quantitative test was developed and evaluated multicentrically on a large and complete panel of 725 clinical plasma samples, covering HCV genotypes 1–6, from four continents (Germany, UK, Brazil, South Africa, Singapore). To our knowledge, this is the most diversified and comprehensive panel of clinical and genotype specimens used in HCV nucleic acid testing (NAT) validation to date. The lower limit of detection (LOD) was 18.4 IU/ml (95% confidence interval, 15.3–24.1 IU/ml), suggesting applicability in donor blood screening. The upper LOD exceeded 10−9 IU/ml, facilitating viral load monitoring within a wide dynamic range. In 598 genotyped samples, quantified by Bayer VERSANT 3.0 branched DNA (bDNA), X-tail-based viral loads were highly concordant with bDNA for all genotypes. Correlation coefficients between bDNA and X-tail NAT, for genotypes 1–6, were: 0.92, 0.85, 0.95, 0.91, 0.95, and 0.96, respectively; X-tail-based viral loads deviated by more than 0.5 log10 from 5′-NCR-based viral loads in only 12% of samples (maximum deviation, 0.85 log10). The successful introduction of X-tail NAT in a Brazilian laboratory confirmed the practical stability and robustness of the X-tail-based protocol. The assay was implemented at low reaction costs (US$8.70 per sample), short turnover times (2.5 h for up to 96 samples), and without technical difficulties.

Conclusion

This study indicates a way to fundamentally improve HCV viral load monitoring and infection screening. Our prototype assay can serve as a template for a new generation of viral load assays. Additionally, to our knowledge this study provides the first open protocol to permit industry-grade HCV detection and quantification in resource-limited settings.  相似文献   
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This article argues that feminist analyses of patriarchy should be expanded to address the evolutionary basis of male motivation to control female sexuality. Evidence from other primates of male sexual coercion and female resistance to it indicates that the sexual conflicts of interest that underlie patriarchy predate the emergence of the human species. Humans, however, exhibit more extensive male dominance and male control of female sexuality than is shown by most other primates. Six hypotheses are proposed to explain how, over the course of human evolution, this unusual degree of gender inequality came about. This approach emphasizes behavioral flexibility, cross-cultural variability in the degree of partriarchy, and possibilities for future change. This work was supported in part by NSF grant BNS-8857969. Barbara Smuts is a professor of psychology and anthropology at the University of Michigan. She received her B.A. in social anthropology at Harvard and her Ph.D. in bio-behavioral sciences at Stanford Medical School. She has studied the behavior of wild chimpanzees, baboons, and bottlenose dolphins and is particularly interested in evolutionary, comparative analyses of female-male relationships.  相似文献   
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