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排序方式: 共有279条查询结果,搜索用时 31 毫秒
41.
Ma Chih-Ming Ku Young Kuo Yu-Lin Chou Yiang-Chen Jeng Fu-Tien 《Water, air, and soil pollution》2009,197(1-4):313-321
Water, Air, & Soil Pollution - The decomposition of gaseous isopropanol (IPA) by UV/TiO2 process in an annular photoreactor was studied under various conditions such as UV light intensity and... 相似文献
42.
本实验根据PRRSV结构蛋白的特性和IFNγ及IL-2这两种细胞因子的特性,构建表达PRRSVGP4-GP5、GP5-M、GP5-N、GP5-IFNγ、GP5-IL-2、N-IFNγ、N-IL-2的重组质粒。这些重组质粒在真核细胞中得到了表达。用这些真核表达质粒可以免疫小猪,通过检测其对猪体免疫应答的诱导能力和接种后动物对PRRSV的抵抗力来对基因疫苗的效能进行研究,以期筛选到有效的基因疫苗并为今后进一步的研究提供思路和理论基础。 相似文献
43.
现代居民区生态景观营造越来越受人们关注。文章阐述了居住区绿化的构成要素、发展趋势及基本原则,可供居住区园林设计者参考。
相似文献
44.
Lian-Ben Chang Chih-Jen Chou Jia-Shian Shiu Po-An Tu Shi-Xuan Gao Shao-Yu Peng Shinn-Chih Wu 《Tropical animal health and production》2017,49(6):1157-1162
Our aim was to investigate insemination techniques in order to improve pregnancy rates of artificial insemination (AI) using sex-sorted semen (sexed AI) in cattle in tropical and subtropical (T/ST) regions. In T/ST regions, the pregnancy rates by sexed AI are reportedly the lowest in the hottest months of the year, with less than 15% in cows and 35–40% in heifers (PMID 24048822). We compared sexed AI by depositing the semen into the uterine body (UB-AI, n = 12) versus the unilateral uterine horn (UUH-AI, n = 14) of pre-ovulation heifers. The ovary and follicle were assessed by rectal ultrasound before AI. After insemination, pregnancy was determined by ultrasound at approximately 40 days and approximately 70 days. In the present study, we demonstrated that high pregnancy rates (>70%) by sexed AI in the hottest season in a subtropical region such as Taiwan can be achieved when heifers with pre-ovulation follicles are used. The overall pregnancy rates were 54% higher in the UUH-AI (71%) group than in the UB-AI (42%) group (P = 0.06), examined on approximately 40 days post-sexed AI. Surprisingly, however, the pregnancy outcome appeared to be higher in the hot season (62%) than in the cool season (46%) although this difference was not statistically significant. Based on the present study, we recommend that cattle breeders perform UUH-AI using sex-sorted semen for heifers with pre-ovulation follicles in order to achieve satisfactory pregnancy outcome in the hot seasons in T/ST regions. 相似文献
45.
Chang SC Chen HF Chou MH Wang HC Su HY Wong ML 《Veterinary and comparative oncology》2010,8(4):302-309
Four types of globins for oxygen transport are known in vertebrates, and the haemoglobin is responsible for carrying oxygen in blood. In this study, we found that haemoglobin was also expressed in canine mammary glands. Samples were taken from 26 malignant mammary tumors, 16 normal mammary glands and 10 other normal tissues. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE), immunoblotting and mass spectrometry were used to investigate haemoglobin in mammary tissues. The results indicated that normal canine mammary glands expressed high levels of haemoglobin protein as shown by Coomassie blue staining. The identity of haemoglobin was confirmed by immunoblotting and mass spectrometry, and the mass spectrometry data revealed that both alpha-haemoglobin and beta-haemoglobin were expressed. Relative to normal mammary glands, the levels of haemoglobin expression in mammary tumors were lower. Our results also indicated that the haemoglobin was endogenously produced in mammary gland tissues and was not derived from the erythroid cells. 相似文献
46.
适宜原料压实度改善玉米秸秆厌氧干发酵特性 总被引:1,自引:1,他引:0
干发酵原料中固形物含量高,结构疏松,原料的压实度直接关系到发酵罐的利用率和生产成本。为了探讨原料压实度对厌氧干发酵过程的影响,该文以玉米秸秆粉为试验材料,研究了不同固形物含量(TS)条件下原料压实度对厌氧干发酵产气特性及物料特性变化的影响,结果表明:相同TS下,随着压实度的增加,日产气量(基于可挥发性固形物,VS)峰值降低且出峰时间略有滞后;原料压实度对累积产气量、日产气量变化趋势以及甲烷体积分数的影响不明显。基于发酵罐容积计算产气量时,原料压实度与日产气量峰值、累积产气总量以及累积甲烷产量均呈显著正相关。不同TS条件下的原料压实度对厌氧干发酵过程的影响程度不同,TS含量越高原料压实度对产气量的影响越明显。TS为20%和25%时,逐层压实发酵罐的单位容积累积产气量比自然填料罐分别提高了37.1%和60.2%。当发酵料初始TS为20%时,原料压实度的增加可促使物料中形成连续的液相,改善物料层间的传质,从而使发酵料上下层间的差异减小。当发酵料初始TS提高到25%时,原料压实度增加对传质特性无明显影响。综上所述,在该试验研究范围内,提高原料压实度可以保证玉米秸秆厌氧干发酵产气过程的正常进行,且可以显著提高发酵罐的容积利用率。该研究对厌氧干发酵原料压实度与发酵特性之间的关系进行了初步探讨,以期为有效提高厌氧干发酵罐的产能能力提供参考。 相似文献
47.
农业机械化工程研究生创新能力的研究 总被引:1,自引:0,他引:1
研究生教育作为我国教育结构中的高层次的教育,有责任而且有义务为国家培养高水平、高素质,且具备高层次创新能力的人才,教育体系应加强创新教育,逐步提高研究生的创新能力.在了解了农业机械化工程学科现状与进展后,提出了农业机械化工程学科研究生创新能力培养的建议:进行创新性学习,提高创新意识和创新思维;学校改进教学课程体系;多参... 相似文献
48.
Eight new cembranoids, crassarines A-H (1-8) were isolated from the Formosan soft coral Sinularia crassa. Compounds 1-3 represent the rare cembranoids with a 1,12-oxa-bridged tetrahydrofuran ring, while 4 and 5 are the firstly discovered 1,11-oxa-bridged tetrahydropyranocembranoids. The absolute configuration of 6 was determined using the Mosher's method. Compounds 6 and 8 were found to significantly inhibit the expression of both pro-inflammatory iNOS and COX-2 proteins at 10 μM, respectively, while compounds 4-8 were found to be non-cytotoxic toward the selected human liver cancer cells. 相似文献
49.
Hsiao-Wei Wen Hsiao-Ping Chung Ya-Ting Wang Po-Chow Hsieh I-Hsin Lin Fong-In Chou 《Postharvest Biology and Technology》2008,50(2-3):208-215
This study examines the protective effects of gamma irradiation against postharvest insect damage and microbial contamination and its effect on the nutritive value of adlay (Coix lacryma-jobi L.). Adlay was treated with doses of 0–20 kGy gamma irradiation and subsequently stored at ambient temperature. The number of insects, microbial quality and chemical properties of irradiated and non-irradiated adlay were evaluated immediately after treatment and after 6 months of storage. Before irradiation, total aerobic microbial counts ranged from 5.6 × 102 to 1.4 × 105 CFU g−1 and the mean total number of insects was 3.2 ± 2.1 per 100 g of polished kernel. Two kilograys was the lowest dose that provided 100% insect control. A radiation-resistant bacterium, Deinococcus radiodurans RC1, was found in 2 of 10 adlay samples. Four kilograys was a sufficient dose for Enterobacteriaceae inactivation, and 6 kGy was a sufficient dose for yeast and fungi inactivation. Twenty and 8 kGy sufficed for the inactivation of all mesophilic microbes in samples with and without D. radiodurans, separately. Moreover the moisture, ash, crude fiber, crude fat, crude protein and riboflavin content all remained constant. However, 8 kGy irradiation reduced vitamin B1 concentration by 24.2%, but did not measurably reduce the amount of amino acids, except methionine and cysteine. Fatty acid contents did not alter after 8 kGy irradiation, but changes were observed after the 6 months of storage. These changes caused by irradiation were no greater than those caused by the 6-month storage. Irradiation up to 8 kGy did not markedly increase the acid value, but did increase the peroxide value to 13% of the initial value right after irradiation. However, significant changes in acid value and peroxide value were noted after 6 months of storage both in non-irradiated and post-irradiated storage samples. Additionally, 8 kGy irradiation did not significantly change the adlay appearance. The improvement in the hygiene of this vital food source compensates for the small loss of some nutritional constituents. Hence 8 kGy of gamma irradiation can be used in cold decontamination of adlay to prolong shelf-life, to improve postharvest quality, and to reduce the risk of food-borne disease. 相似文献
50.