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41.
Combination chemotherapy is superior to single-agent chemotherapy for treating canine lymphoma, but the effect of each drug on efficacy remains unknown. By comparing 34 dogs treated with a modified cyclophosphamide, vincristine, prednisone (COP) chemotherapy protocol and 42 dogs given asparaginase in the induction phase of the same protocol, the effect of asparaginase on the chemotherapeutic protocol was determined. Both groups were compared based on clinical response at 2 weeks and 6 weeks, and on the progression-free interval. Asparaginase did not significantly increase the likelihood of a clinical remission or prolong the initial progression-free interval in the dogs studied.  相似文献   
42.
Solid phase microextraction (SPME) coupled to gas chromatography-mass spectrometry (GC-MS) was employed for the headspace determination of the volatile organic fraction emitted by two of the most common Mediterranean demosponges, Ircinia variabilis and Sarcotragus spinosulus, and of indole and some biogenic amines released by sponges in an aqueous medium. A total of 50/30 µm divinylbenzene/carboxen/polydimethylsiloxane and 75 µm carboxen/polydimethylsiloxane fibers were used for the headspace extraction of low molecular weight sulfur compounds from a hermetically sealed vial containing sponge fragments, while the direct immersion determination of indole and biogenic amines was performed. The biogenic amines were extracted after in-solution derivatization with isobutyl chloroformate. All analytical parameters (linearity, limits of detection, and quantification, precision, and recovery) were evaluated for indole and biogenic amines. SPME-GC-MS proved to be a reliable means of highlighting the differences between molecules released by different sponges, principally responsible for their smell. The combined approaches allowed the identification of several volatile compounds in the headspace and other molecules released by the sponges in an aqueous medium, including indole and the BAs cadaverine, histamine, isobutylamine, isopentylamine, propylamine, 2-phenylethylamine, putrescine and tryptamine. The results obtained represent a further contribution to the picture of odoriferous molecules secreted by sponges.  相似文献   
43.
The fundamental step in the identification of the most appropriate strategy for the remediation of sites contaminated with dense nonaqueous phase liquids (DNAPLs) is a comprehensive characterization of the contaminated source region as the morphology of DNAPL strongly governs the mass transfer processes. The influence of DNAPL distribution geometry and groundwater flow velocity on mass reduction was explored through the evaluation of a series of laboratory studies conducted in a two-dimensional tank under different hydrodynamic conditions. An image analysis procedure was used to determine the distribution of DNAPL saturation and the morphology of the contaminated region. Experimental observations revealed a dependence of mass transfer rate on the aqueous phase velocity under high flow regimes, whereas the mass transfer rate was controlled mainly by morphometric indexes under low velocity flow conditions. Experimental results indicate that higher mass reduction and contaminant fluxes are obtained at low saturation values. The mass flux emanating from an elongated source aligned perpendicularly to the direction of water flow is greater due to a higher DNAPL?Cwater contact surface in comparison to a lower mass flux from horizontal pools with high saturation. These aspects should be considered in an inverse modeling technique for locating the source zone and also in all remediation approaches based on an increase in water circulation through a contaminated zone (i.e., pump and treat).  相似文献   
44.
Orange juice is a source of antioxidants that might afford in vivo protection from oxidative stress. To test this hypothesis, we carried out a human intervention study with blood orange juice containing high amounts of vitamin C, anthocyanins, and carotenoids. Sixteen healthy female volunteers were enrolled in a crossover study and were given 600 mL/day of blood orange juice or a diet without juice for 21 days. Before and after each intervention period, plasma vitamin C, cyanidin-3-glucoside, and carotenoids were quantified. Furthermore, plasma antioxidant capacity, malondialdehyde concentration in plasma, 11-dehydrotromboxane B(2) urinary excretion, and lymphocyte DNA damage were evaluated as biomarkers of oxidative stress. Blood orange juice consumption determined a significant increase in plasma vitamin C, cyanidin-3-glucoside, beta-cryptoxanthin, and zeaxanthin. Also, lymphocyte DNA resistance to oxidative stress was improved whereas no effect was observed on the other markers that we analyzed. In turn, these results suggest that blood orange juice is a bioavailable source of antioxidants, which might moderately improve the antioxidant defense system; however, the long-term effects of its consumption are to be further investigated.  相似文献   
45.
The use of transgenic plants as delivery system for antigenic proteins is attractive for its simplicity and increases likelihood for local immune response at sites of infection. The aim of this study was to evaluate the protective effect of oral administration of tobacco seeds, expressing the FedA, the major protein of the F18 adhesive fimbriae, and B subunit of verocytotoxin, against verocytotoxin-producing E. coli (VTEC) strain in piglets. Forty-three early weaned piglets, were randomly divided into 4 experimental groups: 3 test groups and a control. Treatment groups orally received a bolus, with different dose of tobacco seeds on 0, 1, 2, 14 days post primary administration. After challenge, with 1*1010 CFU of O138 Escherichia coli strain, piglets showed clinical scores significantly higher in the control group compared to orally immunized groups (P?<?0.05) and the latter showed a faster recovery than in CG. In conclusion, oral administration of recombinant tobacco seeds expressing antigenic proteins against VTEC strains can induce a protective effect against challenger strain in piglets.  相似文献   
46.
47.
A nutritional supplement (Ecotrofin™, by Vetoquinol Italia S.r.l) recommended in ruminants feeding to strengthen the physiological condition and improve digestive performance was tested in 20 pluriparae grazing goats divided in two groups (control and treated) to assess its possible effects on milk yield and quality and to assess eventual adverse effects. Animals from both groups also received 400 g/day of corn meal, and the treated group was supplemented with 20 g/head/day of the nutritional supplement. At the doses suggested by the manufacturer, despite a transient increase after 30 days of supplementation, Ecotrofin™ did not show significant effects on milk yield and, although some changes were found in the fatty acids profile, no significant improvement of MUFA and PUFA, as well as of omega-6:omega-3 ratio and CLA content were seen. Therefore, in our experimental conditions the supplementation of diet with Ecotrofin™ did not appear useful to improve goat's performance. A significant effect on kidney health markers (27 vs. 22.5 for urea and 0.83 vs. 0.76 for creatinine, < 0.05) suggested a beneficial effect on renal function but, since levels fell in the normal ranges in both groups, such hypothesis would need further studies to be addressed.  相似文献   
48.
Inhibition of polyphenol oxidases activity by various dipeptides   总被引:1,自引:0,他引:1  
In an effort to develop natural and nontoxic inhibitors on the activity of mushroom polyphenol oxidase (PPO) the effect of various glycyl-dipeptides (GlyAsp, GlyGly, GlyHis, GlyLeu, GlyLys, GlyPhe, GlyPro, GlyTyr) was investigated. The inhibition study with dihydroxyphenylalanine (DOPA) as substrate is based on separation of the enzymatic reaction components by reversed phase HPLC and the UV detection of the dopachrome formed. The results have evidenced that several of tested dipeptides inhibited PPO activity in the range of 20-40% while GlyPro and GlyLeu had no effect. The study has also permitted the characterization of the following kinetic pattern: a linear-mixed-type mechanism for GlyAsp, GlyGly, GlyLys, and GlyPhe and a hyperbolic-mixed-type for GlyTyr. It was not possible to identify the inhibition mechanism for GlyHis, although it affects PPO activity. In addition the effects of GlyAsp, GlyLys and GlyHis were evaluated for lessening the browning of fresh Golden Delicious apple and Irish White Skinned potato. The effectiveness of such inhibitors was determined by the difference between the colors observed in the dipeptide-treated sample and the controls using the color space CIE-Lab system. The % browning inhibition on potato (20-50%) was greater than of apple (20-30%) by the all tested dipeptides. Only GlyLys presented the significant value of 50%.  相似文献   
49.
Multiple published studies involving computed tomographic (CT) examinations of the equine head utilise a wide range of mAs parameters for image acquisition. This prospective, experimental study assessed the effects of lowering mAs during CT image acquisition on image quality and scatter radiation on 10 cadaver equine heads. Each head was scanned three times at 300, 225, and 150 mAs, with all other scanning parameters remaining constant between series. An anthropomorphic phantom was positioned adjacent to each equine head during image acquisition, mimicking a human bystander, with an ionization chamber attached to the phantom at eye level. Each series was reconstructed using filtered back projection, using medium (H30) and high (H80) frequency reconstruction algorithms. Quantitative image quality assessment was performed by calculating signal to noise ratio (SNR) and contrast to noise ratio (CNR). Two qualitative image quality assessments were performed independently by three blinded board certified veterinary radiologists with a 4 week interval, using a visual grade analysis model adapted from peer reviewed medical literature. Ionization chamber measurements, calculated volume CT dose index (CTDIvol), and dose‐length product (DLP) were recorded. Halving radiation dose during image acquisition from 300 to 150mAs resulted in comparable image quality between series. There was a statistically significant and linear relationship between mAs and scatter radiation to the bystander; halving mAs during image acquisition resulted in halving of scatter radiation. Results of this cadaveric study support the use of lower mAs settings during standing CT examinations of the equine head.  相似文献   
50.
Three extracts of different polarities of Glycyrrhiza glabra L. leaves were characterized and evaluated for their antioxidant, anti-genotoxic and anti-inflammatory activity. In total, thirty components have been identified and quantified through the use of liquid chromatography (LC) with ultraviolet-visible diode-array-detector (UV-vis-DAD) and mass spectrometry (MS). The main components belong to the polyphenols family, being flavonoid and dihydrostilbene derivatives. The extracts have been investigated for their antioxidant, anti-genotoxic and anti-inflammatory activities, which are fundamental requirements of efficacious chemo-preventive agents. The ethyl acetate extract proved to be the most valuable, evidently for the conspicuous presence of several polyphenols, namely flavonoids and dihydrostilbenes.  相似文献   
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