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201.
We describe the draft genome of the microcrustacean Daphnia pulex, which is only 200 megabases and contains at least 30,907 genes. The high gene count is a consequence of an elevated rate of gene duplication resulting in tandem gene clusters. More than a third of Daphnia's genes have no detectable homologs in any other available proteome, and the most amplified gene families are specific to the Daphnia lineage. The coexpansion of gene families interacting within metabolic pathways suggests that the maintenance of duplicated genes is not random, and the analysis of gene expression under different environmental conditions reveals that numerous paralogs acquire divergent expression patterns soon after duplication. Daphnia-specific genes, including many additional loci within sequenced regions that are otherwise devoid of annotations, are the most responsive genes to ecological challenges.  相似文献   
202.
Immunotherapeutic strategies have shown promise for the treatment of canine osteosarcoma (cOSA). Very little is known about the immune microenvironment within cOSA, however, limiting our ability to identify potential immune targets and biomarkers of therapeutic response. We therefore prospectively assessed the disease‐free interval (DFI) and overall survival time (ST) of 30 dogs with cOSA treated with amputation and six doses of adjuvant carboplatin. We then quantified lymphocytic (CD3+, FOXP3+) and macrophage (CD204+) infiltrates within the primary tumours of this cohort using immunohistochemistry, and evaluated their association with outcome. Overall, the median DFI and ST were 392 and 455 days, respectively. The median number of CD3+ and FOXP3+ infiltrates were 45.8 cells/mm2 (4.6‐607.6 cells/mm2) and 8.5 mm2 (0‐163.1 cells/mm2), respectively. The median area of CD204+ macrophages was 4.7% (1.3%‐23.3%), and dogs with tumours containing greater than 4.7% CD204+ macrophages experienced a significantly longer DFI (P = 0.016). Interestingly, a significantly lower percentage of CD204+ macrophages was detected in cOSA arising from the proximal humerus compared to other appendicular bone locations (P = 0.016). Lymphocytic infiltrates did not appear to correlate with outcome in cOSA. Overall, our findings suggest that macrophages may play a role in inhibiting cOSA progression, as has been suggested in human osteosarcoma.  相似文献   
203.
The methanol extract of stems of Catalpa ovata G Don exhibits potent in vivo antifungal activity against Magnaporthe grisea (Hebert) Barr (rice blast) on rice plants, Botrytis cinerea Pers ex Fr (tomato grey mould) and Phytophthora infestans (Mont) de Bary (tomato late blight) on tomato plants, Puccinia recondita Rob ex Desm (wheat leaf rust) on wheat plants and Blumeria graminis (DC) Speer f. sp. hordei Marchal (barley powdery mildew) on barley plants. An antifungal substance was isolated and identified as dehydro-alpha-lapachone from mass and nuclear magnetic resonance spectral data. It completely inhibited the mycelial growth of B. cinerea, Colletotrichum acutatum Simmonds, Colletotrichum gloeosporioides Simmonds, M. grisea and Pythium ultimum Trow over a range of 0.4-33.3 mg litre(-1). It also controlled the development of rice blast, tomato late blight, wheat leaf rust, barley powdery mildew and red pepper anthracnose (Colletotrichum coccodes (Wallr) S Hughes). The chemical was particularly effective in suppressing red pepper anthracnose by 95% at a concentration of 125 mg litre(-1).  相似文献   
204.
Advanced glycation end-products (AGEs) play a vital role in the pathogenesis of diabetic complications. Methylglyoxal (MGO), one of the major precursors of AGEs, is a highly reactive dicarbonyl compound that plays an important role in the pathogenesis of diabetic nephropathy. This study was designed to evaluate the therapeutic potential of phlorotannin-rich Ecklonia cava extract (ECE) on MGO-induced diabetic nephropathy in in vitro models using mouse glomerular mesangial cells. ECE showed anti-glycation activity via breaking of AGEs-collagen cross-links and inhibition of AGEs formation and AGE-collagen cross-linking formation. The renoprotective effects were determined by assessing intracellular reactive oxygen species (ROS) and MGO accumulation, cell apoptosis, and the Nrf-2/ARE signaling pathway. MGO-induced renal damage, intracellular ROS production level, and MGO-protein adduct accumulation were significantly decreased by pretreating ECE. Moreover, ECE pretreatment exhibited preventive properties against MGO-induced dicarbonyl stress via activation of the Nrf2/ARE signaling pathway and reduction of RAGE protein expression in mouse glomerular mesangial cells. Collectively, these results indicated potential anti-glycation properties and prominent preventive effects of ECE against MGO-induced renal damage. Additionally, ECE may be utilized for the management of AGE-related diabetic nephropathy.  相似文献   
205.
Zinc oxide (ZnO) and silicon carbide (SiC) nanoparticles were compounded with polyethylene terephthalate (PET) by using a twin screw extruder, and their effect on the UV absorption and heat transfer in PET/ZnO and PET/SiC composite films was investigated. The presence of ZnO and SiC in the PET matrix was verified by X-ray diffraction. The UV absorbance of both PET/ZnO and PET/SiC composite films increased with increasing particle content. The UV absorbance of PET/SiC was higher than that of PET/ZnO under the same particle content. A thermal imaging camera was used to analyze the heat transfer in PET/ZnO and PET/SiC composite films after heating them to 40 °C. As the content of ZnO and SiC particles increased, the temperature decreased more rapidly. PET/SiC showed faster cooling than PET/ZnO because of the higher thermal conductivity of SiC compared to that of ZnO. Response temperature surfaces for PET/ZnO and PET/SiC were obtained by using an exponential decay function and a second order equation, and the elapsed times to cool to room temperature were estimated.  相似文献   
206.
This study was conducted to evaluate the effects of dietary supplementation of Barodon, an anionic alkali mineral complex, on growth, feed utilization, humoral innate immunity and disease resistance of olive flounder. A basal experimental diet was used as a control and supplemented with 0.1, 0.2, 0.3, 0.4, or 0.5% Barodon. Triplicate groups of fish (26.4 ± 0.2 g) were fed one of the diets to apparent satiation twice daily for 10 wk. The growth performance was enhanced (P < 0.05) linearly and quadratically in fish fed diets containing Barodon compared with that in fish fed the control. Feed utilization was significantly improved by Barodon supplementation. Serum lysozyme and antiprotease activities were increased quadratically in Barodon fed groups. Also, significantly higher superoxide dismutase activity was found in Barodon‐fed fish. Dietary supplementation of 0.1–0.3% Barodon resulted in significant enhancement of fish disease resistance against Streptococcus iniae. The findings in this study indicate that dietary supplementation of Barodon can enhance growth, feed utilization, innate immunity, and disease resistance of olive flounder and that the optimum level seems to be 0.1% in diets.  相似文献   
207.
Polyurethane (PU) copolymer is laterally linked with three kinds of metal ion indicator (calcein, calmagite, or eriochrome black T), with which free metal ion in aqueous solution is intended to be detected by PU color change. Metal ion detection by the indicator-PU fails due to the poor permeation of hydrophilic metal ion into hydrophobic PU layer. Instead, three surfactants with different ionic head groups, aerosol OT (AOT), cetyltrimethylammonium bromide (CTAB), and sodium dodecylsulfate (SDS), are tested for metal ion. Cationic CTAB exhibits an instant PU color change, but anionic AOT and SDS do not respond at all. Reason for the selective detection of cationic surfactant is the complex formation between cationic surfactant and indicator. Molecular interactions between PUs are affected by the laterally linked indicators based on the results by infrared spectra and differential thermal analysis. UV-vis spectra reveal that extra peak arising from the linked indicator appears compared to plain PU. The lateral linking of indicator to PU demonstrates, as well as the selective surfactant detection, a 454 % increase in tensile strength and reproducible shape recovery as high as 99 % compared to plain PU.  相似文献   
208.
In order to change for the good flavor in green tea of middle or low grade,roast naked barley (miner ingredient) was added to it.To make tea having functional property,mixed roast naked barley-green tea with one medicinal herb (MH,miner ingredient).This study was performed to investigate the effect of drinking extracts of naked barley-MH-green tea (A group) and adlay-Angelica gigas Nakai-green tea (B group) on the body weights of rats,and volatile flavor components of best effective extract on weight reduction.Forty-eight male Sprague-Dawley rats divided into six groups were fed five different green tea extracts for 8 weeks.The result obtained in the experiment indicated that the change of body weights of rats was affected by A group,B group and others.A group showed highest reduction rate of body weights (36.40%).Reduction rate of body weights on the B group (10.10%) was much lower than A group (36.40%).Aroma compounds were extracted by the SDE method.The concentrated aroma extracts were analyzed and identified by GC and GC-MS.The main aroma components of the green tea blended with naked barley and MH were 12 pyrazines having roasty note,methyl butanals having sweet note,hexanal having briskness greenish note,and nerolidol and3-ionone having floral note.  相似文献   
209.
Meropenem, a second carbapenem antimicrobial agent with a broad spectrum of activity, is used to treat sepsis and resistant‐bacterial infections in veterinary medicine. The objective of this study was to identify the pharmacokinetics of meropenem in dogs receiving intermittent hemodialysis (IHD) and to determine the proper dosing in renal failure patients receiving IHD. Five healthy beagle dogs were given a single i.v. dose of 24 mg/kg of meropenem and received IHD. The blood flow rate, dialysate flow, and ultrafiltration rate were maintained at 40 mL/min, 300 mL/min, and 40 mL/h, respectively. Blood samples were collected for 24 h from the jugular vein and from the extracorporeal arterial and venous line. Urine samples and dialysate were also collected. The concentrations of meropenem were assayed using HPLC/MS/MS determination. The peak plasma concentration was 116 ± 37 μg/mL at 15 min. The systemic clearance was 347 ± 117 mL/h/kg, and the steady‐state volume of distribution was 223 ± 67 mL/kg. Dialysis clearance was 71.1 ± 34.3 mL/h/kg, and the extraction ratio by hemodialysis was 0.455 ± 0.150. The half‐life (T1/2) in dogs with IHD decreased compared with those without IHD, and the reduction in T1/2 was greater in renal failure patients than in normal patients. Sixty‐nine percent and 21% of the administered drug were recovered by urine and dialysate in the unchanged form, respectively. In conclusion, additional dosing of 24 mg/kg of meropenem after dialysis could be necessary according to the residual renal function of the patient based on the simulated data.  相似文献   
210.
A durable aroma finishing for PET fabric was carried out by adopting poly(vinyl acetate) (PVAc) nanoparticles containing lavender oil (LO) in core. Relatively small size of PVAc nanoparticles (ca. 244 nm of mean particle diameter) was expected to resist the frictional destruction of the particles, which is frequently observed in cases of microcapsules. PVAc nanoparticles containing LO in core were prepared by emulsification-diffusion method and their application as an aroma releasing agent for PET fabrics was assessed through the observation of releasing profiles of LO in ethanol for experimental acceleration. Melamine-formaldehyde (MF) microcapsules containing LO were also prepared and treated on fabrics for comparison. PVAc nanoparticles treated on PET fabric showed higher initial releasing amount, which was ascribed to the enhanced surface area. After 2 days of releasing, PET fabric treated with PVAc nanoparticles showed slower and more stable releasing profile and reached about 12 ppm of cumulative release after 16 days, which was under two thirds of that with MF microcapsules. PVAc nanoparticles can be used as an agent for durable aroma finishing of PET fabrics.  相似文献   
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