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121.
In this study, the effect of serum paraoxonase-1 (PON-1) activity on superovulation response and embryo yield was evaluated. The study material comprised 50 Holstein cows aged 3–4 years on postpartum day 90–120 with a body condition score of 3–3.25. A progesterone-based estrus synchronization protocol was initially administered to the selected donors. For this purpose, progesterone source was inserted intravaginally (day 0) and gonadotropin-releasing hormone injection was performed (day 6). Seven days after the insertion of progesterone device, follicle-stimulating hormone injections (total dose of 500 µg in decreasing doses for 4 days) were administered for superovulation. On the morning of the ninth day, prostaglandin (PG) F2α was administered, and the progesterone device was removed from the vagina in the evening on the same day. Two days after PGF2α administration, fixed-time artificial insemination was performed in the morning and in the evening. On the day of artificial insemination, blood samples were taken from the donors to determine the serum PON-1 activity. Uterine flushing was performed seven days after insemination. The results revealed that the serum PON-1 activity (mean ± SD, 562.71 ± 140.23 U/l) of the cows that responded to superovulation (donors with total corpus luteum count of ≥3 in both ovaries) was higher than those (389.91 ± 80.51 U/l) that did not (P<0.05). On the day of insemination, a positive correlation was determined between serum PON-1 activity and the counts of total corpus luteum (r=0.398), total oocyte/embryo (r=0.468), transferable embryo (r=0.453), and Code I embryos (r=0.315, P<0.05). Unlike the Code I embryos, there was no significant correlation between serum PON-1 activity and the number of Code III embryos. Moreover, no significant difference in the number of Code III embryos between the two PON-1 groups was observed. However, embryo yield and quality were found to have increased with increased PON-1 activity. Therefore, it was concluded that serum PON-1 activity may be associated with superovulation response, embryo yield and quality in donor cows.  相似文献   
122.
A comprehensive lignin structure analysis of ten industrially relevant hardwood species is presented. Milled wood lignin (MWL) was isolated from each species using a modified protocol and all milled wood lignin preparations were analyzed through quantitative (13)C NMR spectroscopy, elemental analysis, methoxyl analysis, sugar analysis, and nitrobenzene oxidation. Nitrobenzene oxidation and ozonation were carried out on extractive-free wood, alkali-extracted wood, milled wood lignin, and alkali-extracted lignin. Milled wood lignin isolated by the modified protocol was found to be representative of the total lignin in alkali-extracted wood. Significant variations in lignin structures, such as syringylpropane/guaiacylpropane ratio (S/G ratio), arylglycerol-β-aryl ether (β-O-4), degree of condensation, and elemental and methoxyl contents, were found among the hardwood species studied. These structural variations among species appear to be correlated to a single factor, the syringyl/guaiacyl ratio. A new method to predict the S/G ratio of total lignin in wood was developed, using a calibration line established by the syringaldehyde/vanillin (S/V) ratio (nitrobenzene oxidation) and the S/G ratio ((13)C NMR) of milled wood lignin (MWL).  相似文献   
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124.
乌鲁木齐达坂城地区是新疆湿地分布比较集中的地区之一,包括河流、沼泽、湖泊和池塘等。2010年7-8月,先后2次在该地区采集藻类标本,在对标本鉴定过程中,发现新疆鼓藻属新记录有6种,分别为双眼鼓藻(Cosmarium bioculatum)、扁鼓藻(C.depressum)、丘凸鼓藻(C.ochthodes)、厚皮鼓藻(C.pachydermum)、斑点鼓藻(C.punctulatum)和直角鼓藻(C. rectangulare),并描述了其形态学特征。这些新记录的发现,丰富了新疆鼓藻属植物的研究资料。  相似文献   
125.
Present research investigates the mechanical properties of jute-coir fiber reinforced hybrid polypropylene (PP) composite with fiber loading variation and observes the effect of chemical treatment of fiber on property enhancement of the composites. Composites were manufactured using hot press machine at four levels of fiber loading (5, 10, 15 and 20 wt%). Fiber ratio’s were varied (jute:coir=1:1, 3:1 and 1:3) for 20 % fiber loaded composites. Both jute and coir fiber was treated using 5 % and 10 % NaOH solutions. Composites were also prepared using treated fiber with jute-coir fiber ratio of 3:1. Tensile, flexural, impact and hardness tests and Fourier transform infrared spectroscopic analysis were conducted for characterization of the composites. Tensile test of composite showed a decreasing trend of tensile strength and increasing trend of the Young’s modulus with increase in fiber loading. During flexural, impact and hardness tests, the flexural strength, flexural modulus, impact strength and hardness values were found to be increased with increase in fiber loading. All these properties enhanced with the enhancement of jute content except impact strength. 5 % NaOH treatment provided an improving trend of properties whereas, 10 % NaOH treatment showed the reverse one. The FTIR analysis of the composites indicated decrease of hemicelluloses and lignin content with alkali treatment.  相似文献   
126.
为了比较不同机器学习算法在干旱半干旱区春小麦叶片水分含量(leaf water content,LWC)遥感监测中的应用效果及筛选最佳波段组合,在田间尺度上,以春小麦冠层高光谱数据为基础,采用两波段组合形式,计算15种光谱参数(比值植被指数RVI、归一化植被指数NDVI、差值植被指数DVI和12种水分植被指数),通过对抽穗期叶片含水量与光谱参数拟合效果进行对比与分析,分别构建了基于机器学习[人工神经网络(artificial neural network,ANN)、K近邻(K-nearest neighbors,KNN)和支持向量回归(support vector regression,SVR)]和光谱参数的春小麦LWC反演模型,并对模型精度进行验证,以确定有效波段组合。结果表明,小麦抽穗期LWC与冠层高光谱反射率(R784~950)、12种水分植被指数均显著相关(P<0.01);波段组合形式有效地优化了两波段指数的波段组合,在800~1 000 nm区间光谱参数(RVI1046,1057、NDVI1272,1279、DVI1272,1279)的波段组合计算明显提升了其对LWC的敏感性;在不同的机器学习算法中,基于两波段组合光谱参数的KNN算法所见模型对LWC的预测效果(r=0.64,RMSE=2.35,RPD=2.01)优于ANN、SVR两种算法。这说明两波段光谱指数和KNN算法在春小麦叶片水分含量的高光谱遥感估算中具有一定的优势。  相似文献   
127.
Paddy and Water Environment - Rice is critical to maintaining nutritional demand and food security of many Asian and African nations. The high water demanding rice is traditionally cultivated with...  相似文献   
128.
Background:Bispecific antibodies represent an important class of mAbs, with great therapeutic potentials due to their ability to target simultaneously two distinct epitopes. The generation of functional bispecific antibodies with the highest possible yields is particularly critical for the production of these compounds on industrial scales. Anti- CD3 × CD19 bsAb is a bispecific T-cell engager (BiTE) currently used for treating ALL. Herein, we have tried to optimize the expression level of this antibody in mammalian hosts. Methods:WPRE sequence was incorporated at the 3’ end of the expression cassette. This modification resulted in a notable about two-fold increase in the expression of the bsAb in the Expi293 cell line. Results & Conclusion:Follow-up flow cytometry analysis demonstrated the binding properties of the produced antibody at acceptable levels, and in vitro bioactivity assays showed that this product is potent enough for targeting and destroying CD19-positive cells. Our findings show that WPRE enhances the expression of this type of bispecific mAbs in HEK-293 family cell lines. This approach can be used in biopharma industry for the mass production of anti-CD3 × CD19 bispecific antibody. Key Words: Acute lymphoblastic leukemia, Bispecific antibodies, Monoclonal antibody  相似文献   
129.
A 2-year-old intact miniature pinscher bitch that had been on a bones and raw foods diet since birth showed no signs of estrus despite a 40-day course of cabergoline. Elevated levels of thyroxine were detected in the serum (51 nmol/L) and in the juice of the meat (183 nmol/L) fed to the dog. Change in diet and treatment with oral cabergoline resulted in signs of proestrus in 13 d, pregnancy, and normal birth of 5 puppies.  相似文献   
130.
Samples were taken from 100 camel sausages from the different retail markets in Aydin province in the south-west of Turkey and they were tested for the presence of Listeria spp by biochemical methods. Samples were enriched using Listeria Enrichment Broth and they were inoculated onto Listeria Selective Agar. Listeria monocytogenes was isolated from nine samples (9%), Listeria innocua from 14 samples (14%) and Listeria welshimeri from two samples(2%). A 701 bp fragment of listeriolysin O sequence for L. monocytogenes was amplified using specific primers by polymerase chain reaction (PCR) for confirmation of the identification. A random primer (OPA-11) was used in a random amplified polymorphic DNA (RAPD) assay. This detected five different band profiles amongst the L. monocytogenes isolates, indicating a relatively large amount of genetic heterogeneity amongst the nine isolates. The study has highlighted the need for improved strategies for food safety, in particular appropriate hygienic precautions to avoid contamination of sausage during the manufacturing process and appropriate preservation techniques during storage and transport, to prevent transmission of Listeria spp to consumers at home and abroad.  相似文献   
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