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71.
1. A study was conducted to determine the effects of dried broccoli floret (DBF) on egg production parameters, egg quality and apparent nutrient digestibility of laying hens. It was hypothesised that feeding DBF can improve egg quality without adversely affecting layer performance.2. Seventy-two White Leghorn layers aged 62 weeks were randomly allotted to 4 dietary treatments (6 cage replicates with 3 hens each) and fed diets containing 0, 40, 80 and 120 g/kg DBF in feed for 56 d.3. Inclusion of DBF had no effect on feed intake, egg production, feed conversion ratio or egg components. However, egg weight increased (linear effect, P < 0.05) as the level of DBF in the diet increased. Egg breakage strength, eggshell strength and Haugh unit were not influenced by dietary treatments. Egg yolk colour (quadratic effect, = 0.002) and α-tocopherol concentration (quadratic effect, < 0.0001) improved as a result of DBF inclusion. Egg yolk cholesterol concentration was not altered by DBF inclusion. Apparent total tract nutrient (dry matter, organic matter and crude protein) digestibility coefficients decreased (linear effect, P < 0.05) as the level of DBF increased.4. Feeding DBF to layers up to 120 g/kg of the diet had no negative effects on feed intake, egg production and feed efficiency and improved egg yolk colour and α-tocopherol concentration. However, total tract nutrient digestibility coefficients were negatively decreased as a result of DBF inclusion.  相似文献   
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This study investigated the effect of irrigation amount on the concentration of phenolic compounds in olive (Olea europaea L., cv. Arbequina) oil obtained from an intensively-managed orchard in a semi-arid area with a Mediterranean climate in Tunisia. Different irrigation treatments 50% Etc, 75% Etc and 100% Etc were applied to the olive orchard. Oil quality, evaluated using the parameters established to determine the quality level of virgin olive oils (acidity, K232, K270 and peroxide index) was slightly affected by irrigation. However, results showed that irrigation positively affected both fruit and oil quality. In fact, the least irrigation regime (T1), showed a significantly higher content of oleic acid (70.08%), whereas olive oils from more irrigated trees (T2 and T3) had higher contents of palmitic acid (11.64% and 13.14%, respectively) and lower of linoleic acid (approximately 12.7%). However, content of phenolic compounds (hydrophilic and lypophilic), in the oils extracted, strongly differed. In fact, different irrigation regimes applied not only affected the total amount of phenols which were proportional to irrigation (193.2 and 271.87 mg kg−1 for T1 and T3, respectively) except for T2 but also their HPLC profiles. Contrarily to phenols, insignificant differences were observed in the concentration of α-tocopherol between the irrigation treatments studied.  相似文献   
75.
Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen which causes severe morbidity and mortality worldwide. Seventeen Thai medicinal plants were investigated for their activity against MRSA. Garcinia mangostana was identified as the most potent plant, and its activity was traced to the prenylated xanthone, α-mangostin (MIC and MBC values of 1.95 and 3.91 µg/ml, respectively).  相似文献   
76.
滨海盐渍土原土滴灌水盐调控对土壤水力性质的影响   总被引:4,自引:1,他引:3  
为研究滨海盐渍土滴灌原土水盐调控不同处理对土壤导水率(K)、土壤孔隙大小分布常数(Gardnerα)、土壤孔隙对水流贡献率等水力性质的影响,在滨海盐渍土上进行滤层及基质势(-5、-10、-15、-20、-25kPa)处理的原土水盐调控试验。用圆盘入渗仪在-15、-6、-3、0cm4个连续增大的负压下进行入渗测定,并计算不同负压下导水率、土壤孔隙大小分布常数、孔隙级别对水流的贡献率。结果表明:经原土水盐调控后,各处理的饱和导水率、土壤孔隙大小分布常数较对照增大,在-6和-15cm水头下的导水率较对照减少,在-3cm水头下的导水率无明显变化规律。滤层处理下土壤的饱和导水率、-6cm水头下的导水率、土壤孔隙大小分布常数较无滤层处理有显著提高;各处理土壤大孔隙对水流的贡献率大于对照处理,中等孔隙2及小孔隙对水流的贡献率小于对照处理。滤层处理是不同级别土壤孔隙对水流贡献率大小的主要影响因素,其中滤层的土壤大孔隙、中等孔隙1对水流的贡献率显著高于无滤层。可见,经原土水盐调控后,土壤饱和导水率、-6cm水头下的导水率、土壤孔隙大小分布常数明显增加,土壤大孔隙增加,小孔隙减少,土壤结构得到改善。  相似文献   
77.
This study was conducted to determine the impact of antioxidant (α-tocopherol) supplementation in the cryopreservation extender and three different freezing rates (FRs) on quality of post-thaw semen to elaborate a new protocol for stallion semen cryopreservation. Six ejaculates from each of four stallions were subjected to cryopreservation with a commercial extender (Gent, Minitub Iberia, Spain), without any supplementation (control) or supplemented with 2 mM α-tocopherol. The semen was exposed to three different freezing rates between 5°C and −15°C: slow (5°C/min), moderate (10°C/min), and fast (20°C/min). After thawing, the sperm viability (Sybr-14 and propidium iodide [PI]), mitochondrial membrane potential (MMP) (5,5′,6,6′-tetrachloro-1,1′,3,3′tetraethylbenzimidazolyl carbocyanine iodine), lipid membrane peroxidation (LPO; C11-BODIPY581/591), and apoptosis status (fluorescein isothiocyanate–conjugated annexin V and PI) of the plasmatic membrane of each sample were determined by flow cytometry. For both extenders, the percentage of viable cells was higher for spermatozoa cooled at 5°C/min than at 10°C/min and 20°C/min (P ≤ .05). The FR of 20°C/min demonstrated a lower value of MMP than the FR of 5°C/min and 10°C/min (P ≤ .05). The α-tocopherol extender improved (P ≤ .05) post-thaw membrane LPO; however, it did not improved viability and the apoptosis status of the sperm plasmatic membrane after thawing. In conclusion, results clearly indicate that the cryosurvival of stallion spermatozoa is improved when FR of 5°C/min is used from 5°C to −15°C.  相似文献   
78.
本试验利用免疫组织化学SP法,研究了雌激素受体α在大鼠脑中的表达.结果表明,ER_α免疫反应产物主要定位于神经元细胞核,部分区域出现阳性神经元和阳性突起,在海马CA1、CA2辐射层、齿状回、下托的分子层等出现阳性星形胶质细胞;ER_α在脑中表达广泛,免疫反应产物在端脑的隔外侧核、海马锥体细胞层、大脑皮质等,间脑的缰内侧核、下丘脑室旁核、弓状核、视上核等,中脑的动眼神经核,脑桥的脑桥核外侧部等为高密度;在端脑的尾壳核、杏仁中央核、海马CA4区,间脑的下丘脑室周核、缰外侧核等,中脑的黑质致密带,脑桥的脑桥被盖核等为较高密度;在问脑的视前室周核、丘脑后核、中脑的红核、脑桥的脑桥被盖网状核等为中等密度;在端脑的苍白球,间脑的无名质,无免疫反应产物出现.结果显示,雌激素在调节脑的认知和生殖内分泌过程中,ER_α可能起主要作用;雌激素可通过ER_α调节星形胶质细胞功能.  相似文献   
79.
Chen CC  Chuang PH  Chen YS  Yao CH  Chen HM 《Fitoterapia》2011,82(8):1249-1257
Intestinal α-glucosidase performs a physiologically vital function in the digestive process of dietary carbohydrates. Administration of an α-glucosidase inhibitor may retard the digestion and absorption of carbohydrates. Consequently, the rise in postprandial blood glucose could be suppressed. This study developed a novel technology, called “after flowing through immobilized receptor (AFTIR),” for targeting components in herbal medicines with α-glucosidase-suppressing capability. As a result, we reveal that the AFTIR system is a highly-efficient drug screening platform, capable of purifying and identifying active components with α-glucosidase-suppressing capability in herbal medicines.  相似文献   
80.
Li S  Li J  Guan XL  Li J  Deng SP  Li LQ  Tang MT  Huang JG  Chen ZZ  Yang RY 《Fitoterapia》2011,82(7):1081-1085
The various fractions of the barks of Cyclocarya paliurus were systematically tested for hypoglycemic effects in alloxan-induced diabetic rats. The results showed that the chloroform fraction of the 75% EtOH extract of the barks of this plant exhibited significant blood sugar reducing activity, most of which were significantly higher than that of positive-drug metformin hydrochloride. A new compound, together with nine known compounds, was isolated from the most active fraction. The structure elucidation was based on spectroscopic methods, including two-dimensional NMR experiments (1H-1H COSY, HMQC, and HMBC). All of the isolates were evaluated for their α-glycosidase and glycogen phosphorylase inhibitory activities.  相似文献   
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