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951.
952.
ObjectiveTo evaluate the ability of transthoracic echocardiographic aortic flow measurements to discriminate response to a fluid challenge (FC) in healthy anesthetized dogs.Study designProspective experimental study.AnimalsA total of 48 isoflurane-anesthetized dogs (14.2–35.0 kg) undergoing elective surgery.MethodsFluid responsiveness was evaluated before surgery by FC (lactated Ringer’s 10 mL kg–1 intravenously over 5 minutes). Percentage increases in transpulmonary thermodilution stroke volume (ΔSVTPTD) >15% from values recorded before FC defined responders to volume expansion. A group of 24 animals were assigned as nonresponders (ΔSVTPTD ≤15%). When ΔSVTPTD was >15% after the first FC, additional FC were administered until ΔSVTPTD was ≤15%. Final fluid responsiveness status was based on the response to the last FC. Percentage increases after FC in aortic flow indexes [velocity time integral (ΔVTIFC) and maximum acceleration (ΔVmaxFC)] and in mean arterial pressure (ΔMAPFC) were compared with ΔSVTPTD.ResultsAfter one FC, 24 animals were responders. For nonresponders, ΔSVTPTD was ≤15% after one, two and three FCs in eight/24, 15/24 and one/24 animals, respectively. The FC that defined responsiveness increased ΔSVTPTD by 29 (18–53)% in responders and by 8 (–3 to 15)% in nonresponders [mean (range)]. The area under the receiver operating characteristics curve (AUROC) of ΔVTIFC (0.901) was larger than the AUROCs of ΔVmaxFC (0.774, p = 0.041) and ΔMAPFC (0.519, p < 0.0001). ΔMAPFC did not predict responsiveness (p = 0.826). Best cut-off thresholds for discriminating responders, with respective zones of diagnostic uncertainty (gray zones) were >14.7 (10.8–17.6)% for ΔVTIFC and >8.6 (–0.3 to 14.7)% for ΔVmaxFC. Animals within the gray zone were 17% (ΔVTIFC) and 50% (ΔVmaxFC).Conclusions and clinical relevanceChanges in VTI induced by FC can determine responsiveness with reasonable accuracy in dogs and could play an important role in goal-directed fluid therapy.  相似文献   
953.
1. This study investigated effects of conditioning at 5 d of age and food restriction during a hot period on responses to prolonged heat stress of two fast (G1 and G2) and one slower-growing (G3) broiler stocks. 2. Chicks from each stock were divided into 3 groups: control, conditioned (chicks exposed to 36 degrees C for 24 h at 5 d of age) and food restricted (during the heat stress food was withdrawn 2 h before the hot period and chicks were fed between 17.00 and 08.00 h). Prolonged heat stress was induced daily from 28 to 49 d by heating until the ambient temperature reached 32 degrees to 35 degrees C between 10.00 and 17.00 h. 3. Body weights, mortality and rectal temperatures were lower and food conversion higher for stock G3 than G1 or G2. 4. Management procedures used in this study improved food conversion and lowered mortality without affecting body weight. Rectal temperatures of the treated groups were similar to those of the controls.  相似文献   
954.
Removal of NO2 gases in fixed beds was investigatedby using brownish, whitish and regenerated whitish sepioliteand perlite as adsorbents. For this purpose, NO2 wasproduced by reaction of copper with nitric acid. The producedgas was mixed with air and the mixture was sent through a fixedbed. Studies were conducted using various gas flow rates,NO2 concentrations, packing sizes and heights of bed.Remaining NO2 within the gas mixture leaving the column,unadsorbed on packing, was further absorbed by passing itthrough a series of washing bottles, filled by a solution ofNaOH. At the end of the study, it was observed that theadsorption capacity of sepiolites, especially whitishsepiolite, was much higher than that of perlite. Additionally,it was seen that its adsorption capacity increased withincreasing bed height, particle size, NO2 concentrationand decreasing gas flow rate.  相似文献   
955.
Identifying the genetic variants that increase the risk of type 2 diabetes (T2D) in humans has been a formidable challenge. Adopting a genome-wide association strategy, we genotyped 1161 Finnish T2D cases and 1174 Finnish normal glucose-tolerant (NGT) controls with >315,000 single-nucleotide polymorphisms (SNPs) and imputed genotypes for an additional >2 million autosomal SNPs. We carried out association analysis with these SNPs to identify genetic variants that predispose to T2D, compared our T2D association results with the results of two similar studies, and genotyped 80 SNPs in an additional 1215 Finnish T2D cases and 1258 Finnish NGT controls. We identify T2D-associated variants in an intergenic region of chromosome 11p12, contribute to the identification of T2D-associated variants near the genes IGF2BP2 and CDKAL1 and the region of CDKN2A and CDKN2B, and confirm that variants near TCF7L2, SLC30A8, HHEX, FTO, PPARG, and KCNJ11 are associated with T2D risk. This brings the number of T2D loci now confidently identified to at least 10.  相似文献   
956.
The OMEGA/Mars Express hyperspectral imager identified hydrated sulfates on light-toned layered terrains on Mars. Outcrops in Valles Marineris, Margaritifer Sinus, and Terra Meridiani show evidence for kieserite, gypsum, and polyhydrated sulfates. This identification has its basis in vibrational absorptions between 1.3 and 2.5 micrometers. These minerals constitute direct records of the past aqueous activity on Mars.  相似文献   
957.

Although synthetic pesticides are still used to control insect pests, greater efforts have been made to develop healthier and more environmentally friendly pesticides. Because of their insecticidal properties, botanical essential oils (EOs) are considered as promising alternatives to the use of synthetic insecticides. However, little is known about mechanisms underlying the insecticidal activity of most these natural compounds. In the present study, we evaluated the contact toxicity and the modes of action of the EO from Mentha arvensis against the granary weevil, Sitophilus granarius L. (Coleoptera: Curculionidae), a cosmopolitan insect pest that causes extensive damage to stored cereals. M. arvensis EO caused high contact toxicity in S. granarius adults, resulting in a rapid paralysis and rapid alteration of walking behavior. Our label-free quantitative proteomics approach revealed that M. arvensis EO induced dramatic physiological changes in exposed insects. The majority of the differentially expressed proteins (DEPs) were upregulated and are related to the development and functioning of the muscular and nervous systems, cellular respiration, protein synthesis, and detoxification. These results suggest that M. arvensis essential oil is capable of affecting a variety of biological processes, and shed light on the repair mechanisms put in place in surviving insects to counter the damage inflicted. This work opens new perspectives on the proposed mechanisms of insecticidal activity of a promising EO for controlling pests of stored cereals and may represent a first step in the development of novel bio-rational insecticides.

  相似文献   
958.
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of injectable trace minerals (ITM) at the time of weaning on growth, antioxidant, and immune response...  相似文献   
959.
The aim of this research was to determine brain, cerebral hemispheres and cerebellum volume and volume ratios by using stereological methods and investigate morphological differences between female and male New Zealand rabbits. The study was applied on 14-month old (10 male and 10 female) New Zealand rabbits. The materials removed from the cavum cranii using dorsal approach. After following routine histological procedure, paraffin blocks were prepared and cut every seventieth section at 10 μm thickness. Slides were stained with Crossmon's triple stain and photographed. The sectional images obtained were transferred to ImageJ program to estimate grey and white matter volume on cerebral hemispheres and cerebellum with principle of Cavalieri. According to results, there was no asymmetry on the left and right cerebral hemispheres of New Zealand rabbits. In the total hemisphere volume calculated by Cavalieri principle, grey and white matter ratio was 81.57% and 18.43% in female, 82.80% and 17.20% in male. It was found that the white matter was significantly higher in females than males in cerebral hemispheres (p < .05). Also, it was found that grey and white matter ratio in total cerebellum volume was 67.82% and 32.18% in female, 67.94% and 32.06% in male respectively. It was determined that the females' white matter was larger than male rabbits in cerebellum (p < .05). It is thought that morphometric data obtained from this study will contribute to the existing anatomical knowledge and also considered as reference values in the clinical sciences.  相似文献   
960.
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