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71.
72.
α-蒎烯分子中四元环上的亲核加成反应研究   总被引:3,自引:1,他引:2  
松节油与二硫化碳和氢氧化钠反应,采用2种不同的工艺,可以分别合成萜烯二硫代羧酸钠和萜烯黄原酸钠.并对2种化合物的光谱行为进行了测定.  相似文献   
73.
The object of this investigation was to determine the relationships between clinical findings and hormonal patterns in primiparous sows with different lactation length and litter size during lactation, weaning and to the first oestrus. Seven pairs of primiparous full sib sows were used to determine the effect of lactation length with normal litter size. One sow of each pair was assigned to nurse the piglets for 3 weeks (group A) while the other nusred for 5 weeks (group B). Another 8 primiparous sows (group C) were assigned to nurse 2–4 piglets during a 5-week lactation period. Oestrus detection was performed twice daily and laparoscopic examination every 2 weeks. If the sows did not come in oestrus within 3 weeks after weaning they were slaughtered. Peripheral plasma levels of progesterone, oestradiol-17β and LH were estimated by radioimmunoassays throughout the experimental period.  相似文献   
74.
Shoot cultures were established from nodal explants of 3 pear cultivars by subculture on Murashige and Skoog medium containing mixtures of 3 cytokinins. Zeatin and 6·(γ,γ-dimethylallylamino)purine were both supplied at 10 μM and benzyladenine as follows: ‘William's Bon Chrétien’, 6 μM; ‘Packham's Triumph’, 8 μM; ‘Beurré Bosc’, 10 μM. Production of axillary shoots was greater by basal explants (4–6) comprising the remnants of the previous subculture than by apical explants (2–3) comprising the distal parts of extension shoots. Up to 80% of microcuttings of all cultivars formed roots in vitro with either γ-indolebutyric acid, 10 μM, or α-naphthaleneacetic acid, 10 μM, and approximately 50% of rooted microcuttings were successfully established as container-grown plants. Use of aseptic methods for producing own-rooted pears is discussed in relation to fruit growing and fruit improvement.  相似文献   
75.
Neutrophils (polymorphonuclear leukocytes: PMNs) are essential for the host defense against various infections and are often injurious to the host, causing inflammatory diseases where tumor necrosis factor-alpha (TNF-alpha) is suggested to play an important role. Since an effect of TNF-alpha on canine PMN apoptosis has not been studied, canine PMNs were stimulated with recombinant human (rh)TNF-alpha in the present study to investigate the effect of TNF-alpha on canine PMN apoptosis. PMN apoptosis and function to produce ROS were assessed by flow cytometry. Delayed apoptosis was observed in the PMNs treated with rhTNF-alpha at 100 ng/ml, accompanied by retention of capability to produce ROS. However, PMN apoptosis was accelerated by rhTNF-alpha combined with cycloheximide. Therefore, it is indicated that TNF-alpha is able to activate anti- and pro-apoptotic pathways in PMNs and that the inhibition of PMN apoptosis by TNF-alpha requires protein synthesis in the PMNs.  相似文献   
76.
The scabicide, lindane induces oxidative stress and immunological alterations. The present study was undertaken to assess the ameliorative effects of antioxidant supplementation in lindane treated scabies patients. Scabies patients were treated with either 1% lindane or 1% lindane along with antioxidant (Lycored or Vitamin-E). Oxidative stress and immunological parameters were evaluated in blood samples and compared with healthy controls. Lindane caused a significant increase in malonedialdehyde (MDA) levels and decrease in reduced glutathione (GSH) and ferric reducing ability of plasma (FRAP), which was attenuated by anti-oxidant therapy. The IL-1α levels were significantly enhanced in scabies patients per se and remained unaffected after lindane/anti-oxidant treatment. The TNF-α and nitroblue tetrazolium (NBT) reduction levels were not significantly different in all the groups. Topical application of lindane induces significant free radical generation and may cause immunological alterations which can be reversed by antioxidant therapy.  相似文献   
77.
通过研究光活化杀虫活性成分 α -三联噻吩( α -T)对红火蚁 Solenopsis invicta Buren工蚁觅食行为和触角识别功能的影响,探讨了光活化成分用于控制红火蚁的可行性。用Potter喷雾法将100 μg/mL的 α -T丙酮水溶液喷施于红火蚁中型工蚁体表,再经紫外(UVA)光照射30 min,在处理后5、10、15、20和30 min时,试蚁对火腿肠的识别率分别为20.00%、25.00%、38.33%、40.00% 和41.67%,对杀虫剂饵料的识别率分别为3.33%、0、0、3.33%和0,聚集率分别为17.50%、38.33%、 32.50%、45.00%和48.33%;经100 μg/mL的 α -T涂抹试蚁触角再经紫外光照处理30 min后,触角对丙酮反应的电位值为-0.177 mV,可正常行走的工蚁比率为75.00%;以100 μg/mL的 α -T涂抹试蚁触角并经紫外光照射30 min后10 h,红火蚁的死亡率为27.50%;上述结果均与 α -T黑暗处理、对照(CK)光照处理和CK黑暗处理结果差异显著。 α -T对红火蚁工蚁食物识别和探路行走能力均具有良好的光活化抑制作用,以其防治红火蚁具有良好可行性。  相似文献   
78.
依据GenBank已发表的猪干扰素α1(poIFN-α1)成熟肽基因序列,胸腺肽α1(THY-α1)蛋白序列及Escherichia coliB密码子使用频率表,优化并人工合成poIFN-α1和THY-α1基因,利用SOE-PCR法在poIFN-α1和THY-α1之间设计1个13肽Linker。将融合基因克隆至pRSFDue-t 1表达载体,转化BL21(DE3)感受态,37℃培养至菌液OD600为0.6~0.8,IPTG(0.5 mmol/L)诱导,20℃培养12h,SDS-PAGE和Western blot鉴定。结果表明:目的蛋白为菌体内可溶性表达,经强阴离子交换层析和疏水层析纯化获得高纯度poIFNα1-THYα1融合蛋白。  相似文献   
79.
为弄清红曲霉在降脂减肥方面的作用,进一步开发红曲产物类药物应用于市场,以产红曲红色素的红曲霉菌株为出发菌株,经60Co诱变,对抑制与膳食相关的α-淀粉酶、胰蛋白酶和脂肪酶3种酶活性的红曲霉菌株进行了选育。结果表明:选育出1株能显著抑制3种与膳食相关酶的突变菌株M3-19,菌株M3-19液体发酵产物对α-淀粉酶、胰蛋白酶、脂肪酶有明显的抑制作用,抑制率分别为55.83%、25.4%和31.5%。经传代10代遗传稳定。  相似文献   
80.
研究了水培条件下不同浓度α-萘乙酸(α-NAA)对茉莉(Jasminum sambac Ait.)枝条生根及根尖解剖结构的影响。结果表明:不同浓度的α-NAA对茉莉水培生根率、生根数和根长均有显著影响,以200 mg/Lα-NAA浸泡2 h处理的生根效果最好,培养30 d时生根率达100%,平均每株生根16.6条,平均根长3.5 cm。与蛭石扦插(CK)相比,随着α-NAA处理浓度的增加,水培处理所生根尖的根冠长度、气腔的数量和大小均有所增加。  相似文献   
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