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991.
Immune mechanisms in 2 strains of Salmo salar (Baltic salmon from River Ume Alv in Sweden and East Atlantic salmon from River Skjern? in Denmark) infected with the monogenean ectoparasite Gyrodactylus salaris were elucidated by molecular tools (real-time PCR). The gene expression in the fins (the preferred microhabitat of the parasite) of the susceptible but responding Swedish salmon was compared to the expression in the fins of the highly susceptible and nonresponding East Atlantic salmon. Experimental infections confirmed that both the Swedish and the Danish salmon allowed initial propagation of the parasite on the fins for a few weeks. Baltic salmon subsequently activated a response from Day 28 and limited the parasite population to a few parasites per host within the following weeks. In contrast, the Danish salmon did not respond and experienced a continuing increase in the parasite load during the same period, which reached several hundreds of parasites per host. RNA was isolated from fins of the 2 salmon strains during the course of infection and subsequent real-time PCR showed an increased expression of INFgamma, Mx and MHC I genes in Baltic salmon fins during large segments of the response phase. No upregulation of these genes could be detected in susceptible salmon. No increase in immunoglobulin genes was seen in any of the fish strains, which supports the notion that antibodies are not involved in the response. Further, the work suggests that cellular factors could at least partly contribute to the anti-parasitic response in Baltic salmon.  相似文献   
992.
Abstract: In an article on the role of temporal information in life-cycle assessment in this journal, Field and colleagues argued that frequently it is not the single product but the "fleet" (or cohort) of products that "is the appropriate unit of analysis," and that in focusing on the fleet one "explicitly introduces the notion of time as a critical element of comparative life-cycle assessments. …" Major transitions, such as replacement of one fleet of products by an alternative fleet, correspond to a system in a transient rather than steady state, and explicit consideration of time is central to transient analysis.
One tool increasingly used as part of life-cycle assessment, economic input-output (EIO) analysis, at best deals with time in an implicit fashion. This article illustrates how the sequential interindustry model (SIM), a formulation of the EIOmodel that explicitly represents time, might be utilized in life-cycle assessment. SIM introduces this temporal component by explicitly accounting for the time required by production activities and the resulting sequencing of the inputs. This can be thought of as engineering rather than accounting information. The data demands of such a model are not likely to be met at present or at any time in the near future. Even so, simulation methods and the use of so-called synthetic data have a history of productive use in a number of fields, including the social sciences.
SIM also utilizes the contribution of Joshi on the application of the EIO model to environmental impact and the inclusion of the use as well as the production phases of a product in EIO analysis. The possibility of accounting for discounting of future events, with its impact on decision making, is also briefly discussed.  相似文献   
993.

Background

Obesity is a major health problem. Although heritability is substantial, genetic mechanisms predisposing to obesity are not very well understood. We have performed a genome wide association study (GWA) for early onset (extreme) obesity.

Methodology/Principal Findings

a) GWA (Genome-Wide Human SNP Array 5.0 comprising 440,794 single nucleotide polymorphisms) for early onset extreme obesity based on 487 extremely obese young German individuals and 442 healthy lean German controls; b) confirmatory analyses on 644 independent families with at least one obese offspring and both parents. We aimed to identify and subsequently confirm the 15 SNPs (minor allele frequency ≥10%) with the lowest p-values of the GWA by four genetic models: additive, recessive, dominant and allelic. Six single nucleotide polymorphisms (SNPs) in FTO (fat mass and obesity associated gene) within one linkage disequilibrium (LD) block including the GWA SNP rendering the lowest p-value (rs1121980; log-additive model: nominal p = 1.13×10−7, corrected p = 0.0494; odds ratio (OR)CT 1.67, 95% confidence interval (CI) 1.22–2.27; ORTT 2.76, 95% CI 1.88–4.03) belonged to the 15 SNPs showing the strongest evidence for association with obesity. For confirmation we genotyped 11 of these in the 644 independent families (of the six FTO SNPs we chose only two representing the LD bock). For both FTO SNPs the initial association was confirmed (both Bonferroni corrected p<0.01). However, none of the nine non-FTO SNPs revealed significant transmission disequilibrium.

Conclusions/Significance

Our GWA for extreme early onset obesity substantiates that variation in FTO strongly contributes to early onset obesity. This is a further proof of concept for GWA to detect genes relevant for highly complex phenotypes. We concurrently show that nine additional SNPs with initially low p-values in the GWA were not confirmed in our family study, thus suggesting that of the best 15 SNPs in the GWA only the FTO SNPs represent true positive findings.  相似文献   
994.
Objective: Severe obesity is a clear indication for appropriate, effective weight loss therapy. One option is operative intervention, e.g., gastric banding. Risks of the operation and therapeutic alternatives need to be comprehensibly presented to the patient. The literature has shown that better informed consent is obtained using information presented in a multimedia/video‐based format. The current study developed and evaluated a multimedia program aimed at obtaining informed consent from obese patients before gastric banding. Research Methods and Procedure: An interactive multimedia program was developed with information about preoperative examinations, the operation itself, hospital stay, operative risks, alternative therapies, and the pathophysiology and health risks of obesity. Two groups (Group 1, n = 20, mean age 38 years, informed consent attained with conventional document information; Group 2, n = 20, mean age 37 years, informed consent attained with additional multimedia information) were interviewed regarding comprehensibility of the information presented, personal satisfaction, and anxiety levels during the informed consent process. Results: Group 2 showed significantly better (p < 0.05) understanding of the presented information and higher levels of satisfaction with the informed consent process. Anxiety levels did not significantly differ between the two groups. Discussion: Because patient satisfaction with the informed consent process and understanding of the presented information significantly improved, the multimedia program clearly benefits both surgeons and patients. Personal contact from the surgeon remains essential. High volumes of information presented in multimedia format do not alleviate patient anxiety, and personal contact may be beneficial.  相似文献   
995.
996.
Systemic vasculitis, an inflammatory necrotizing disease of the blood vessel walls, can occur secondary to autoimmune diseases, including connective tissue diseases. Various pathogenic mechanisms have been implicated in the induction of vasculitis, including cell-mediated inflammation, immune complex-mediated inflammation and autoantibody-mediated inflammation. This inflammatory activity is believed to contribute to accelerated atherosclerosis, and also leads to increased risk for cardiovascular events in patients with rheumatoid arthritis and systemic lupus erythematosus. Endothelial cell activation is a common pathogenic pathway in the systemic vasculitis associated with rheumatoid arthritis and systemic lupus erythematosus, with elevated levels of endothelin-1 potentially inducing vascular dysregulation.  相似文献   
997.
Two-dimensional crystallization on lipid monolayers is a versatile tool to obtain structural information of proteins by electron microscopy. An inherent problem with this approach is to prepare samples in a way that preserves the crystalline order of the protein array and produces specimens that are sufficiently flat for high-resolution data collection at high tilt angles. As a test specimen to optimize the preparation of lipid monolayer crystals for electron microscopy imaging, we used the S-layer protein sbpA, a protein with potential for designing arrays of both biological and inorganic materials with engineered properties for a variety of nanotechnology applications. Sugar embedding is currently considered the best method to prepare two-dimensional crystals of membrane proteins reconstituted into lipid bilayers. We found that using a loop to transfer lipid monolayer crystals to an electron microscopy grid followed by embedding in trehalose and quick-freezing in liquid ethane also yielded the highest resolution images for sbpA lipid monolayer crystals. Using images of specimens prepared in this way we could calculate a projection map of sbpA at 7A resolution, one of the highest resolution projection structures obtained with lipid monolayer crystals to date.  相似文献   
998.
999.
1000.
A method is presented to study dynamics of plants that cannot be separated into individuals such as many grassland, salt marsh and tundra species. A virtual population is created by using a permanent transect line through the vegetation and individuals are defined as the branch segments distal to the intercept with the transect line. Addition and loss of individuals together with growth or shrinkage form the basis for constructing a size-structured transition matrix. A discrete-event simulation demonstrates that: 1) a virtual population of individuals grows at the same rate as the parent population; and, 2) size-structured transition matrices for a virtual population and parent vegetation have similar dominant and subdominant eigenvalues so a virtual population can be used to describe the dynamics of a parent vegetation.Dwarf birch, Betula nana L., was studied in the northern foothills of the Brooks Range, Alaska, by using photography to record branch intercepts along permanent transect lines. The distal branch segments constitute a virtual population of the parent vegetation. Transects were photographed in 1985 and again in 1986 and changes of branch segments were used to construct two transition matrices for shrubs with and without elevated fertilizer treatment. Analysis of the virtual populations suggests that although Betula nana may show increased branch growth with increased fertilizer, in the long run this shrub may decline in the tundra in response to such treatment.  相似文献   
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