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61.
AIM: To determine the half life (T1/2), time taken to reach maximum plasma concentration (Tmax) and maximum plasma concentration (Cmax) of thalidomide in sheep following I/V, oral and topical treatment with a single dose of thalidomide.

METHOD: Three groups of 4–6-month-old ram lambs were treated with thalidomide dissolved in dimethylsulphoxide (DMSO). The first group (n=10) was treated I/V with 100?mg thalidomide in 2?mL DMSO; the second group (n=8) received 400?mg thalidomide in 2?mL DMSO orally, and the third group (n=8) had 400?mg thalidomide in 4?mL DMSO applied topically. Plasma samples were collected up to 36 hours after treatment, snap-frozen at ?80°C and analysed for concentrations of thalidomide using high performance liquid chromatography.

RESULTS: Following I/V administration, T1/2 was 5.0 (SEM 0.4) hours, volume of distribution was 3,372.0 (SEM 244.3) mL/kg and clearance was 487.1 (SEM 46.1) mL/hour.kg. Topical application of 400?mg thalidomide did not increase plasma concentrations. Following oral administration, thalidomide bioavailability was 89%, with T1/2, Tmax, and Cmax being 7.2 (SEM 0.8) hours, 3.0 (SEM 0.4) hours and 1,767.3 (SEM 178.1) ng/mL, respectively.

CONCLUSION: Topical administration using DMSO as a solvent did not increase concentrations of thalidomide in plasma. The mean pharmacokinetic parameters determined following oral treatment with 400?mg of thalidomide were similar to those reported in humans receiving a single 400?mg oral dose (T1/2 7.3 hours; Tmax 4.3 hours and Cmax 2,820?ng/mL). There is potential for thalidomide to be used as a model for the treatment of chronic inflammatory conditions in sheep, such as Johne's disease, where tumour necrosis factor alpha plays a pathogenic role.  相似文献   
62.
 构建胸腺肽αl(Thymosin αl,Tαl)基因原核表达载体,并在大肠杆菌BL21中进行表达,为大量获得胸腺肽αl打下基础。将人工合成的Tαl三串体基因插入到表达载体pET32a后,CaC12法转化大肠杆菌BL21,经氨苄青霉素筛选后用IPTG诱导表达,SDS-PAGE检测BL21中胸腺肽αl的表达。大肠杆菌中检测到与目的蛋白相对分子量(31kD)相符的条带。成功构建了Tαl原核表达载体,该蛋白能在大肠杆菌中表达。  相似文献   
63.
为快速培育7S球蛋白致敏蛋白α-亚基缺失的优质大豆新品系,以(α'+α)-亚基双缺失型材料日B为供体亲本,东农47为受体亲本,以杂交-回交转育方法为基础,结合SSR标记辅助遗传背景选择与主要农艺性状鉴定及品质分析,在BC2F4选育到7S球蛋白α-亚基缺失新品系Cb80。Cb80综合农艺性状优良,遗传背景回复率大于90%,其蛋白质及氨基酸总量为44.1%、41.95%,分别比轮回亲本东农47提高3.5和3.76个百分点。  相似文献   
64.
65.
The α-amylase inhibitor from corms of Colocasia collected from Bhota village of Hamirpur district, Himachal Pradesh was purified to 17.21 folds with 61.61% recovery using ammonium sulfate precipitation, gel filtration chromatography (sephadex G-200) and ion exchange chromatography (DEAE-sephadex). A single band of the purified inhibitor was obtained by Native-PAGE. SDS-PAGE revealed the purified inhibitor to be a monomer with molecular weight of 13,900 daltons. The nature of inhibition was found to be of non-competitive type as determined by Lineweaver-Burk plot and a Ki value of 0.54 nmole was obtained by Dixon’s plot. The inhibitor was found to be heat stable and retained 81.50% activity at 70 °C temperature. Inhibitor was found to have pH optima of 6.9. The purified inhibitor was found to have inhibitory activity against α-amylases extracted from the larvae of Callosobruchus chinensis, Tribolium castaneum, Corcyra cephalonica and midgut α-amylase of Spodoptera littoralis. 100% larval mortality of C. cephalonica was observed when fed on wheat flour mixed with 0.0036% (w/w) of purified inhibitor. Purified α-amylase inhibitor was found to inhibit the activity of human salivary α-amylase. It also had inhibitory activity against potato α-amylases and reduced sugar content in treated potato slices. The purified inhibitor was found to be a glycoprotein. In the present study, the ability of the inhibitor to inhibit insect amylases highlights its possible role in pest resistance and post harvest decay of crop plants. Inhibitory activity of α-amylase inhibitor against mammalian amylases could suggest its potential in treatment of diabetes and cure of nutritional problems, which result in obesity.  相似文献   
66.
67.
棉铃虫Gq蛋白α亚基基因的克隆及组织特异性表达   总被引:2,自引:0,他引:2  
 【目的】了解棉铃虫体内Gqα的组织特异性表达情况。【方法】利用RACE技术获得了Gqα全长基因,利用半定量RT-PCR研究了该基因的时空表达情况。【结果】从棉铃虫Helicoverpa armigera触角中克隆了一条全长1 101bp的Gqα cDNA序列,命名为GqαHarm;阅读框全长1 062 bp,编码353个氨基酸残基。GqαHarm与已报道的昆虫Gq蛋白α亚基同源性在90%以上,与近缘种甘蓝夜蛾Mamestra brassicae Gqα的同源性高达96.88%,与家蚕Bombyx mori Gqα的同源性高达97.73%。半定量RT-PCR研究表明,GqαHarm在棉铃虫雌雄成虫触角中表达,在头、胸、腹、足和翅中也有表达,并且表达量差异不显著;此外,在喙、下颚须和下唇须中也有表达;在卵、幼虫、蛹和成虫体内也都有表达;在卵中的表达量最高,而在成虫中的表达量最低,在幼虫和蛹的前、中、后期的表达量差异不大。【结论】研究表明GqαHarm是一种在棉铃虫体内普遍存在的蛋白。  相似文献   
68.
目的:了解慢性肾衰(CRF)患者血清及尿可溶性白细胞介素-2受体(sIL-2R)、白细胞介素-8(IL-8)和肿瘤坏死因子-α(INF-α)水平的变化及意义。方法:采用双抗体夹心ELISA法检测36例CRF患者及40例健康对照组血清及尿sIL-2R、IL-8及INF-α水平。结果:CRF患者血清及尿中上述3种因子均显著高于正常对照组(P〈0.001),但与血清肌酐(Scr)无明显相关性(相关系数分  相似文献   
69.
柞蚕蛹在18℃恒温发育阶段,蛹体内α—生育酚和胆固醇含量有明显变化。感温前10天蛹体α—生育酚含量提高2~5倍,10天后明显下降。而胆固醇含量随着感温天数显著下降,成蛾时几乎不含胆固醇。因此,蛹体内α—生育酚和胆固醇含量的变化,可作为判断茧蛹感温发育阶段的依据。  相似文献   
70.
JIN Qi  XIONG Li-xia 《园艺学报》2014,30(8):1513-1518
IL-13 is a pleiotropic cytokine mainly secreted by activated Th2 cells. It has 2 receptors, IL-13Rα1 and IL-13Rα2. The latter had been thought to serve exclusively as a decoy receptor for a long period of time due to its short cytoplasmic tail and lack of signal transduction structure. Since Fichtner-Feigl reported in Nature Medicine that IL-13 is involved in induction of TGF-β production and tissue fibrosis through IL-13Rα2-mediated signaling pathway, it was found that IL-13Rα2 has more sophisticated functions than just a simple decoy receptor as more and more researches have explored its signaling functions. This review combines the most advanced research results with previous investigation and discusses the gene structure, expression, production, distribution, subtype conversion and possible signal pathways mediated by this receptor. More importantly, the connection with human diseases and the applications in disease diagnosis and molecule targeted therapy for cancer are also discussed.  相似文献   
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