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排序方式: 共有134条查询结果,搜索用时 15 毫秒
1.
Power and energy management for server systems   总被引:4,自引:0,他引:4  
Bianchini  R. Rajamony  R. 《Computer》2004,37(11):68-76
This survey shows that heterogeneous server clusters can be made more efficient by conserving power and energy while exploiting information from the service level, such as request priorities established by service-level agreements.  相似文献   
2.
Corn grits spiked with 30 microg/g fumonisin B1 and two batches of grits fermented with Fusarium verticillioides (batch 1 contained 33 microg/g, and batch 2 contained 48 microg/g fumonisin B1), which were extruded by a single-screw extruder with and without glucose (10%, dry weight basis) supplementation were fed to rats. Control groups were fed uncontaminated grits. Extrusion with glucose more effectively reduced fumonisin B1 concentrations of the grits (75 to 85%) than did extrusion alone (10 to 28%). With one exception, the fumonisin B1-spiked and fermented extrusion products caused moderately severe kidney lesions and reduced kidney weights, effects typically found in fumonisin-exposed rats. Lesions in rats fed the least contaminated grits (batch 1) after extrusion with 10% glucose were, however, significantly less severe and not accompanied by kidney weight changes. Therefore, extrusion with glucose supplementation is potentially useful for safely reducing the toxicity of fumonisins in corn-based products and studies to determine the optimal conditions for its use are warranted.  相似文献   
3.
Inflammation may increase cancer risk, therefore, we studied whether polyphenol‐rich Marie Ménard (MM) apples with reported anti‐inflammatory activity prevent 1,2‐dimethylhydrazine (DMH)‐induced colon carcinogenesis in rats and, likewise whether high‐fat (HF) diet promoting carcinogenesis, may affect inflammation. DMH‐induced rats were fed for 15 weeks with: an HF diet (23% corn oil w/w); an HF diet containing 7.6% w/w lyophilized MM (apple diet (AD)); a low‐fat (LF) diet and an HF diet containing piroxicam (PXC) (0.01% w/w) as control. Mucin depleted foci (MDF), precancerous lesions in the colon, were dramatically reduced in the AD, LF, and PXC groups compared with the HF. Peritoneal macrophage activation, an index of systemic inflammation, was significantly decreased in the AD, LF, and PXC groups. TNFα, iNOS, IL‐1β, IL‐6 m‐RNA expression in the colon, as well as CD68 cells and plasmatic PGE2 were lower in the AD, but not in the LF group. Apoptosis in the MDF of both the AD and LF‐fed rats was significantly higher than in HF rats. In conclusion, AD has a strong chemopreventive effect, reducing inflammation, and increasing apoptosis, while the chemopreventive effect of the LF diet seems mediated mainly by increased apoptosis in MDF.  相似文献   
4.
5.
Hospital-acquired pneumonia (HAP) is a frequent cause of nosocomial infections, responsible for great morbidity and mortality worldwide. The majority of studies on HAP have been conducted in patients hospitalized in the intensive care unit (ICU), as mechanical ventilation represents a major risk factor for nosocomial pneumonia and specifically for ventilator-associated pneumonia. However, epidemiological data seem to be different between patients acquiring HAP in the ICU vs. general wards, suggesting the importance of identifying non ICU-acquired pneumonia (NIAP) as a clinical distinct entity in terms of both etiology and management. Early detection of NIAP, along with an individualized management, is needed to reduce antibiotic use and side effects, bacterial resistance and mortality. The present article reviews the pathophysiology, diagnosis, treatment and prevention of NIAP.  相似文献   
6.
In order to compare the last version of the Respiratory Virus Panel (RVP) Fast assay for human Adenovirus (hAdv) detection with a specific real-time polymerase chain reaction (qPCR), which is considered the gold standard for hAdv detection, nasopharyngeal samples collected from 309 children (age range, four months to eight years) with respiratory tract infection were tested using the RVP Fast v2 assay (Luminex Molecular Diagnostics, Inc., Toronto, ON, Canada) and a specific TaqMan qPCR to identify hAdv DNA. The RVP Fast v2 assay detected 30/61 (49.2%) hAdv infections that had been identified by real-time qPCR, demonstrating a significantly lower detection rate (p < 0.001). The sensitivity of the RVP Fast v2 assay in comparison to qPCR was lower in younger children (42.9% vs. 57.7%; Cohen’s kappa coefficient, 0.53); in samples with co-infections (40.0% vs. 56.7%; Cohen’s kappa coefficient, 0.52); and in samples with hAdv type C (45.9% vs. 57.1%; Cohen’s kappa coefficient, 0.60). Samples with lower viral loads were associated with a significantly lower sensitivity of the RVP Fast v2 assay (35.1% vs. 68.2%, p = 0.01; Cohen’s kappa coefficients, 0.49). The RVP Fast v2 assay has important limitations for the detection of hAdv and cannot be used to evaluate whether hAdvs are the main etiologic agent responsible for an outbreak or when epidemiological studies are performed.  相似文献   
7.
Arena  G.E.  Bianchini  A.  Centi  G.  Vazzana  F. 《Topics in Catalysis》2001,16(1-4):157-164
The transient reactivity and surface phenomena of storage and conversion of NO x species on Pt(1%)–Me/Al2O3 catalysts, where Me = Ba, Ce and Cu, were studied by the RWF (rectangular wavefront) method. The Me component has a relevant influence on the processes of surface storage and transformation. The reduction of NO x by propene in the presence of oxygen is promoted by adding Cu to a Pt/Al2O3 catalyst, while cerium promotes transient conversion of NO in the absence of propene, but inhibits the reduction of NO x in the presence of propene. Copper is suggested to be a promising element to add together with Ba for new NO x storage-reduction catalysts due to its capacity to act both as a storage element and as promoter for NO x reduction.  相似文献   
8.
The clonal composition of a malignant tumor strongly depends on cellular dynamics influenced by the asynchronized loss of DNA repair mechanisms. Here, our aim was to identify founder mutations leading to subsequent boosts in mutation load. The overall mutation burden in 591 colorectal cancer tumors was analyzed, including the mutation status of DNA-repair genes. The number of mutations was first determined across all patients and the proportion of genes having mutation in each percentile was ranked. Early mutations in DNA repair genes preceding a mutational expansion were designated as founder mutations. Survival analysis for gene expression was performed using microarray data with available relapse-free survival. Of the 180 genes involved in DNA repair, the top five founder mutations were in PRKDC (n = 31), ATM (n = 26), POLE (n = 18), SRCAP (n = 18), and BRCA2 (n = 15). PRKDC expression was 6.4-fold higher in tumors compared to normal samples, and higher expression led to longer relapse-free survival in 1211 patients (HR = 0.72, p = 4.4 × 10−3). In an experimental setting, the mutational load resulting from UV radiation combined with inhibition of PRKDC was analyzed. Upon treatments, the mutational load exposed a significant two-fold increase. Our results suggest PRKDC as a new key gene driving tumor heterogeneity.  相似文献   
9.
Semicrystalline linear low density polyethylenes (LLDPEs) with exclusively ethyl branching (from 7 to 56 branches per 1,000 carbon atoms) were prepared from ethylene by homogeneous tandem catalytic systems comprising (imino)pyridine cobalt(II) dichlorides as oligomerization precursors, bis(cyclopentadienyl)zirconium(IV) dichloride as copolymerization precursor and methyaluminoxane as activator. The activity of the tandem systems was evaluated by varying either the molar fraction of the cobalt precursors or the ethylene pressure. The latter parameter was of crucial importance to control both the productivity and the extent of 1-butene incorporation. In particular, increasing the ethylene pressure from 2 bar to 4 bar changed the “comonomer effect” from positive to negative.  相似文献   
10.
Fish constitutes a very important part of human diet due to its protein content. The poor commercialization system existing in Costa Rica for this product causes an important secondary contamination that may include microorganisms such as fecal coliforms, Staphylococcus aureus and even pathogens such as Listeria monocytogenes. There is a lack of recent information about the microbiological quality of the fish that arrives to the Metropolitan Area of San José, Costa Rica, so the aim of this work was to study it through the detection of microbiological indicators and the incidence of L. monocytogenes. Five different samplings were realized to 27 fisheries located in two different areas from San José, Costa Rica: the Central Market and the rest of the Metropolitan Area. Each time, a 500 g sample of fresh filleted fish was taken and transported to the Food Microbiology Laboratory, Universidad de Costa Rica, for performing the different analysis, which included the presence/absence of L. monocytogenes, total plate count, total and fecal coliforms count and Most Probable Number of Staphylococcus aureus. Also, a hygiene evaluation of the different fisheries was performed. According to this, 22.2% of the fisheries were classified as excellent, 14.8% as good, 40.8% as regular and 22.2% as bad. Fisheries hygiene is independent of the incidence of L. monocytogenes with a 95% confidence level, and there is no significant relationship between hygiene and the other indicators analyzed. There is a significant relationship between the incidence of Listeria sp. and the hygiene of the Central Market area. It was determined that 96.3% and 29.6% of the fisheries accomplish with the microbiological limits established by ICMSF for S. aureus and total plate count, respectively. Listeria sp. was found in 65.2% of the fish samples analyzed. From these, 52.3% was L. monocytogenes, 43.2% L. innocua, 3.4% L. ivanovii and 1.1% L. seeligeri. In 88.9% of the fisheries the presence of L. monocytogenes was positive at least once.  相似文献   
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