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21.
Tan HP  Wong DZ  Ling SK  Chuah CH  Kadir HA 《Fitoterapia》2012,83(1):223-229
The galloylated cyanogenic glucosides based on prunasin (1-7), gallotannins (8-14), ellagitannins (15-17), ellagic acid derivatives (18, 19) and gallic acid (20) isolated from the leaves of Phyllagathis rotundifolia (Melastomataceae) were investigated for their neuroprotective activity against hydrogen peroxide (H2O2)-induced oxidative damage in NG108-15 hybridoma cell line. Among these compounds, the gallotannins and ellagitannins exhibited remarkable neuroprotective activities against oxidative damage in vitro as compared to galloylated cyanogenic glucosides and ellagic acid derivatives in a dose-dependent manner. They could be explored further as potential natural neuroprotectors in various remedies of neurodegenerative diseases.  相似文献   
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研究贝加尔雅罗鱼(Leuciscus baicalensis)感染的单殖吸虫的群落多样性及感染情况,为额尔齐斯河鱼类寄生虫病防治提供基础资料。2009年8月到2016年7月,剖检贝加尔雅罗鱼296尾,共感染了6种单殖吸虫,分别为号筒指环虫(Dactylogyrus tuba Linstow,1878)、双髻指环虫(D. sphyra Linstow, 1878)、小刺指环虫(D. micracanthus Nybelin,1937)、多小枝指环虫(D. ramulosus Malewitzkaja,1941)、普氏三代虫(Gyrodactylus prostate Erergns,1963)和斯氏拟双身虫(Paradiplozoon skrjabini Achmerov,1974);贝加尔雅罗鱼单殖吸虫的总感染率为20.27 %,平均感染强度为3.05只/尾(1~18只/尾),平均感染丰度为(0.62±2)只/尾;混合感染率相对较低,仅占2.36%;各单殖吸虫的感染率均小于10%,平均感染强度均小于5,其中小刺指环虫为优势种;在5个体长段中,在14cm≤L<16cm体长段感染单殖吸虫的种类、感染率及感染强度均达到最高;体长段之间的多样性指数、优势度指数、均匀度指数及丰富度指数结果相差不大,不同体长段宿主中单殖吸虫种群的分布类型均为聚集分布;体长段14cm≤L<16cm与16cm≤L感染强度差异显著,其余体长段之间的感染强度差异均不显著。  相似文献   
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The neutron moisture meter (NMM) is a widely used device for sensing soil water content (SWC). Calibration accuracy and precision of the NMM are critical to obtain reliable results, and linear regression analysis of SWC against NMM count data is the most common method of calibration. In this study, artificial neural network (ANN) calibration models were developed and compared with linear regression. For this purposes, training and validation data were obtained from 2 calibration and 16 testing plots, respectively. Calibration plots consist of wet and dry soil water conditions separately. Data measured in dry beans and red pepper plots that have four different water levels were used to determine validity of regression and ANN-based calibration models. Volumetric SWC and NMM count ratio measurements were taken for depth intervals of 30 cm throughout a 120-cm-deep soil profile. Several neural network architectures were explored in order to determine the optimal network architecture. Data analyses were conducted for each soil layer and for the whole profile, separately, based on both linear regression and ANN. Linear regression calibration equation coefficients of determination (r 2) for the 0–30, 30–60, 60–90 and 90–120 cm depth ranges calculated by regression models were 0.85, 0.84, 0.72 and 0.82, respectively, and r 2 values were 0.94, 0.95, 0.87 and 0.88 based on ANN models, respectively. Using the data set from the entire 120-cm soil profile for calibration by ANN, the r 2 value was raised to 0.97.  相似文献   
25.
Phenylbutazone was administered intravenously and intramuscularly at a dosage rate of 4.4 mg/kg to a group of 6 female camels in a two-period crossover study. After intravenous (i.v.) administration, disposition was characterised by a two-compartment open model, with a low volume of distribution (0.174 l.kg–1), and distribution and elimination half-lives of 0.43 and 12.51 h, respectively. After intramuscular (i.m.) dosing absorption was relatively rapid with absorption half-time and time of maximal concentration values of 1.14 and 3.95 h, respectively. Plateau concentrations of phenylbutazone in plasma were obtained between 2 and 12 h and mean bioavailability was 97%, although this was subject to wide inter-animal differences. Plasma concentrations of the phenylbutazone metabolite, oxyphenbutazone, were low after iv dosing and generally undetectable after im administration, indicating that it is unlikely to contribute significantly to the pharmacological effects produced by phenylbutazone administration. An indication was obtained that phenylbutazone inhibited the ex vivo synthesis of serum thromboxane B2 (TxB2) for 24 h after i.v. dosing, but this finding requires confirmation.  相似文献   
26.
This study assessed the effect of halal slaughter and anesthesia pre‐slaughter followed by bleeding on meat quality characteristics of goats. Eleven male Boer cross goats were divided into two groups and subjected to either halal slaughter (HS) or anesthesia with halothane and propofol pre‐slaughter (AS). At pre‐rigor, HS had significantly lower (P < 0.05) muscle pH and glycogen than AS. However, no significant difference was observed in the pH and glycogen content between the treatments on 1, 3 and 7 days post mortem. The drip loss of HS was significantly lower (P < 0.05) than that of AS at all aging periods. Treatment had no effect on sarcomere length, myofibrillar fragmentation index and shear force values, loss of thiol groups and degradation of major myofibrillar proteins. It can be concluded that HS did not have deleterious effect on meat quality traits of goat when compared to AS.  相似文献   
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The aim of the study was to examine impact of foliar titanium (Ti) sprays on vegetative and reproductive response of apple (Malus domestica Borkh.) trees under conditions of low soil availability of iron (Fe), manganese (Mn), and zinc (Zn). The experiment was conducted during 2005–2006 at a Experimental Station in Isparta region, Turkey, on mature ‘Granny Smith’ apple trees/M.9, planted at a spacing of 3.5 × 1.5 m, on fine-textured soil with neutral reaction, medium status of organic matter, high amounts of available phosphorus (P), potassium (K), and magnesium (Mg), and low availability of Fe, Mn, and Zn. The trees were sprayed with Ti-ascorbate at the green and pink bud stage, petal fall, and 3, 6, and 9 weeks after full bloom, at a rate of 3 g Ti ha?1 per spray. The efficiency of Ti sprays was compared to combined sprays of Fe, Mn, and Zn [chelated with ethylenediaminetetraacetic acid (EDTA)], applied at the same terms as Ti sprays, at rate of 36 g, 36 g and 24 g per spray, respectively. Trees unsprayed with Ti, Fe, Mn, and Zn served as the control. It was shown that summer leaf Ti concentrations of the trees untreated with Ti were high, varying from 34 to 36 mg kg?1 dry matter. Foliar Ti sprays increased leaf status of this nutrient but they had no effect on nutrition of essential macro- and microelements, tree vigor, and fruit yield. Mean apple weight, coloring, firmness, soluble solids concentration, and titratable acidity of fruit were not also influenced by Ti sprays. Foliar sprays of Fe, Mn, and Zn improved leaf status of nitrogen (N), Mg, Fe, Mn, and Zn; leaves of the trees sprayed with those micronutrients were also greener, and contained more Fe2+ than those of the control plants. Combined sprays of Fe, Mn, and Zn improved tree vigor and fruit yield.  相似文献   
29.
The aim of this study was to understand stick-slip properties of para-aramid woven fabrics. For this reason, pullout test was conducted on para-aramid Kevlar®29 and Kevlar®129 woven fabrics. The stick-slip and accumulative retraction force regions were defined based on the force-displacement curve. It was found that the stick-slip force and accumulative retraction force depended on fabric density and the number of pulled ends in the fabric. Stick-slip force in the multiple yarn pull-out test was higher than those of the single yarn pull-out test. Stick-slip force in single and multiple yarn pull-out tests in the dense K29 fabric were higher than those of the loose K129 fabric. In addition, long fabric samples showed high stick-slip force compared to that of the short fabric samples. On the other hand, the amount of stick-slip force was related to the number of interlacement points in the fabric whereas the amount of accumulative retraction force was related to fabric structural response.  相似文献   
30.
Pre-inoculation with the endobacterium Serratia marcescens (strain UPM39B3) induced the production of host defence enzymes such as peroxidase, polyphenoloxidase, phenylalanine ammonia lyase, total soluble phenols and lignothioglycolic acid in banana plantlets. The levels of these enzymes were evidently higher in plantlets pre-treated with the endobacterium compared to the control. The production of host-induced enzymes benefitted the crop plants as they may have a role in suppressing Fusarium wilt incidence in the plantlets. This was evident when plantlets pre-treated with the endobacterium showed a lower disease severity (50%) compared to diseased plantlets lacking the endobacterium (74%). The results of this study thus highlight the potential of the isolate Serratia marcescens (strain UPM 39B3) as a biological control agent for Fusarium wilt management in bananas, reducing disease severity via stimulation of host defences.  相似文献   
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