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11.
DNA sequences of nuclear gene Got2 was studied in 60 accessions of Aegilops tauschii, 29 of subsp. tauschii and 31 of subsp. strangulata. It was found that Got2 allozyme polymorphism in Ae. tauschii is due to a single, unique, mutation which led to replacement of glutamic acid by isoleucine in residue 256 of the enzyme molecule, encoded by Got2. As revealed by Got2 DNA sequences variation, initially in its history Ae. tauschii was presented by subsp. strangulata, and among phylogenetic lineages of subsp. strangulata, the lineage “t-91s” (TauL3) is the most ancient, a relict one. Subspecies tauschii is relatively “young”. Initially it was presented by the lineage marked by combination of allozyme alleles Got2 105 and Acph1 100. In the past it inhabited the Continental area from Caucasia to Pakistan, but later on it was forced out by newly originated, now—a major lineage of subsp. tauschii, marked by Got2 100. This lineage extended the Continental area of the species up to Kirgizstan, but actually failed to penetrate into pre-Caspian area, occupied by subsp. strangulata. These results essentially differ from those obtained previously, using chloroplast DNA (cpDNA) sequences polymorphism. As revealed by cpDNA, the major, “usual”, subsp. strangulata (TauL2) is “younger” than subsp. tauschii, which resided on phylogenetic tree between relict lineage “t-91s”of subsp. strangulata—and major subsp. strangulata. But both cpDNA and Got2 DNA sequences indicate that the level of genetic variation in subsp. tauschii is much lower than in subsp. strangulata. According to Got2 DNA sequences variation, it was Ae. tauschii subsp. strangulata lineage “k-109″ which donated genome D to Triticum aestivum L. This lineage includes accessions: k-109 from South-Eastern Precaspian Azerbaijan; KU-2105, KU-2159 from Western Precaspian Iran; KU-2080 from Eastern Precaspian Iran.  相似文献   
12.
Sargassum muticum (S. muticum) is a brown edible alga and widely distributed in Korea. This report was designed to evaluate the anti-inflammatory properties of apo-9′-fucoxanthinone (APO-9′) isolated from S. muticum on pro-inflammatory cytokine production. S. muticum extract (SME) exhibited significant inhibitory effects on pro-inflammatory cytokine production in bone marrow-derived macrophages (BMDMs) and dendritic cells (BMDCs). APO-9′ pre-treatment in the CpG DNA-stimulated BMDMs and BMDCs showed a strong dose-dependent inhibitory effect on interleukin (IL)-12 p40, IL-6 and tumor necrosis factor (TNF)-α production with IC50 values ranging from 5.31 to 13.79. It exhibited a strong inhibitory effect on the phosphorylation of ERK1/2 and on activator protein (AP)-1 reporter activity. APO-9′ pre-treatment exhibited significant inhibition of CpG DNA-induced production of inducible nitric oxide synthase. Taken together, these data suggest that SME and APO-9′ have a significant anti-inflammatory property and warrant further studies concerning the potentials of SME and APO-9′ for medicinal use.  相似文献   
13.
对用壳聚糖絮凝大豆蛋白发酵液进行研究,讨论pH值、絮凝剂浓度、温度和搅拌时间对絮凝效果的影响,结果是壳聚糖用量200 mg/L、pH值为4、搅拌12 min、温度30℃时效果最好.  相似文献   
14.
西部罗布麻的民族植物学研究   总被引:4,自引:0,他引:4  
从民族植物学的观点介绍了罗布麻在我国西部各民族人民生活中的地位及利用情况,论述了罗布麻的利用价值、分类、地理分布、生物学特性及其研究历史和研究进展。  相似文献   
15.
Glutathione (GSH) concentrations of oocytes are considered as an important marker of the cytoplasmic maturation. The present study was designed to compare GSH concentrations of in vivo and in vitro matured canine oocytes. In vivo matured oocytes were collected 72 hr after ovulation by flushing fallopian tubes after laparotomy. Ovaries were collected from bitches with different reproductive stages, and collected oocytes were divided into 2 groups according to the size viz. < 120 microm and > 120 microm in diameter and cultured for 72 hr in Tissue Culture Medium-199 supplemented with 10% FBS, 2.2 mg/ml sodium bicarbonate, 2.0 microg/ml estrogen, 0.5 microg/ml FSH, 0.03 IU/ml hCG, and 1% penicillin-streptomycin solution in the presence or absence of 50 microM beta-mercaptoethanol. GSH concentrations were determined by the dithionitrobenzoic acid-glutathione disulfide (DTNB-GSSG) reductase recycling assay. GSH concentrations of immature canine oocytes were 2.9 and 3.8, 3.5 and 6.8, and 3.1 and 6.5 pM/oocyte for < 120 microm and > 120 microm in diameter oocyte groups at anestrous, follicular and luteal stage, respectively (P<0.05). In vivo matured oocytes had significantly higher GSH concentrations compared with in vitro matured oocytes. The GSH content was 19.2 pM/oocyte for in vivo matured oocytes, while 4.1 to 8.1 and 5.7 to 13.2 pM/oocyte for in vitro matured oocytes cultured in the absence or presence of beta-mercaptoethanol, respectively (P<0.05). Presence of beta-mercaptoethanol increased GSH synthesis in canine oocytes cultured in vitro, and oocytes collected from follicular and luteal stage was superior to anestrus oocytes.  相似文献   
16.
An 8-week feeding trial was conducted to determine the optimal dietary protein level for juvenile marbled flounder. Five semi-purified test diets were formulated to contain different protein levels (CP) including 42.7%, 47.4%, 53.3%, 58.8%, and 64.5% (dry matter), named as CP42.7, CP47.4, CP53.3, CP58.8, and CP64.5, respectively. Five hundred and twenty-five juveniles (6.0 ± 0.1 g) were randomly distributed into 15 tanks (300 L tanks), resulting in 35 fish per tank (n = 3 tanks). Fish were fed the test diets 5 times per day until satiation. The CP58.8 resulted in the highest gain in weight and the best efficiency in feed utilization among the tested protein levels (P < 0.05). Fish fed the CP58.8 diet showed significantly higher whole-body protein and lipid contents than the fish that were fed the other diets (P < 0.05). Fish fed the CP53.3, CP58.8, and CP64.5 diets showed a significantly higher dorsal-muscle lipid content than the fish that were fed the CP42.7 and CP47.4 diets (P < 0.05). The one-slope straight broken-line regression analysis on the results of the thermal growth coefficient and feed conversion ratio indicated that the estimated optimum dietary protein level was 58.8%. Taken together, it is suggested that the dietary protein level of 58.8% is optimal for better growth and high efficiency in feed utilization for the juvenile marbled flounder.  相似文献   
17.
广西东门林场森林资源现状和可持续发展策略   总被引:1,自引:0,他引:1  
根据广西东门林场2009年森林资源二类调查的结果,分析东门林场森林资源现状、特点及存在的问题,并提出东门林场森林资源可持续发展的策略。  相似文献   
18.
Melatonin affects diverse physiological functions through its receptor and plays an important role in the central nervous system. In the present study, we compared immunoreactivity patterns of arylalkylamine N-acetyltransferase (AANAT), an enzyme essential for melatonin synthesis, and melatonin receptor type 1B (MT2) in the spinal cord of young adult (2~3 years) and aged (10~12 years) beagle dogs using immunohistochemistry and Western blotting. AANAT-specific immunoreactivity was observed in the nuclei of spinal neurons, and was significantly increased in aged dog spinal neurons compared to young adult spinal neurons. MT2-specific immunoreactivity was found in the cytoplasm of spinal neurons, and was predominantly increased in the margin of the neuron cytoplasm in aged spinal cord compared to that in the young adult dogs. These increased levels of AANAT and MT2 immunoreactivity in aged spinal cord might be a feature of normal aging and associated with a feedback mechanism that compensates for decreased production of melatonin during aging.  相似文献   
19.
土壤中南方根结线虫的实时荧光PCR检测和定量   总被引:1,自引:2,他引:1  
为了准确测定土壤中南方根结线虫Meloidogyne incognita的群体密度,根据序列特异性扩增区标记设计了南方根结线虫特异性引物和TaqMan探针,分别建立了卵和2龄幼虫的实时荧光PCR定量检测体系,并将该检测体系与显微镜计数法进行了比较.结果表明,引物Mi-F/R及探针Mi-probe对南方根结线虫具有高度特异性,建立的标准曲线循环阈值与卵和2龄幼虫数量的对数值之间具有良好的线性关系,相关系数分别为0.9771和0.9853,扩增效率均为90%,检测灵敏度为10-1个卵及10-3条2龄幼虫;对10个田间土壤样本的检测显示,实时荧光PCR定量检测与显微镜计数法测定的南方根结线虫卵和2龄幼虫数量呈显著正相关,且两种方法对2龄幼虫的测定结果无显著差异.  相似文献   
20.
利用RT-PCR技术成功扩增出IBV AH1-99分离株的N基因全长cNDA,将其克隆到pMD18-T载体上。经酶切分析、PCR鉴定及核苷酸序列测定,成功获得该分离株N基因的重组质粒。序列分析结果表明,分离株N基因全长1 230个核苷酸,编码409个氨基酸。同部分IBV参考毒株相比,核苷酸同源性为85.8%~89.9%,氨基酸同源性为86.6%~91.0%,在进化关系树中,AH1-99与国内分离株X、LX4亲缘关系较近。  相似文献   
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