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AIM: To investigate the expression of natural killer cell stimulation receptor D(NKG2D) in peripheral blood and the expression of major histocompatibility complex class I chain-related protein A(MICA) on the gastric carcinoma tissue and the neighboring non-cancerous tissue in Tibetan patients with gastric cancer at Qinghai plateau. METHODS: Samples of 33 patients and 20 healthy persons were collected to detect NKG2D in peripheral blood by Flow cytometry analysis. The expressions of MICA in part of the correspondent tissues were examined by RT-PCR and immunohistochemistry.RESULTS: The expression of NKG2D in the plateau of Tibetan patients with gastric cancer group (13.47 ±5.26)% was significantly lower than that in healthy groups (32.62±10.08)%. The mRNA level of MICA in gastric cancer was significantly higher than that in neighboring non-cancerous tissue (P<0.05). The expressions of MICA proteins showed a significant difference between the neighboring non-cancerous tissue (21.21%, 7/33) and the gastric carcinoma tissue (78.79%, 26/33), between the high differentiation (60.00%, 3/5) and the moderate (72.73%, 8/11), low differentiation (88.24%, 15/17). The expressions of MICA were not correlated with tumor size, sex, age, lymph node metastasis of the patients (P>0.05). Spearman rank correlation displayed that the expressions of MICA mRNA were positively correlated with the MICA protein level (r=0.903, P<0.01).CONCLUSION: The immune escape in Tibetan patients with gastric cancer at Qinghai plateau probably relates to the down-regulation of NKG2D and the up-regulation of its ligand MICA. The activity of NK cells and the anti-cancer cellular immunity level are descending in the plateau of Tibetan patients with gastric cancer. The decrease in the receptor NKG2D is a reason for the activity of NK cell descending.  相似文献   
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本研究对槟榔江水牛3-酮酸辅酶A转移酶1(3-oxoacid CoA-transferase 1,OXCT1)基因的完整CDS区进行了PCR扩增,并对其功能生物信息学和多组织差异表达进行了分析。以普通牛OXCT1基因序列(GenBank登录号:XM_006076397)为参考序列,采用Primer Premier 5.0软件设计引物序列,以提取的槟榔江水牛基因组DNA为模板,PCR扩增获得槟榔江水牛OXCT1基因mRNA序列,扩增产物经测序后利用ORF Finder软件进行开放阅读框识别,获得水牛OXCT1基因CDS区全序列,并对其进行生物信息学分析。结果显示,槟榔江水牛OXCT1基因CDS序列全长1 563 bp,编码520个氨基酸,蛋白分子式为C2509H4041N687O746S23,分子质量为56.50 ku,理论等电点(pI)为8.69,不稳定系数为27.49,平均疏水性(GRAVY)为-0.097,该蛋白属弱亲水性蛋白。OXCT1蛋白无信号肽和跨膜结构,属于线粒体膜蛋白;包含pcaJ_scoB_fam和AtoD 2个保守结构域,且具有5个功能活性位点。槟榔江水牛与普通牛、藏羚羊等5个物种的OXCT1氨基酸序列同源性≥ 97%。对槟榔江水牛13个组织进行表达谱分析表明,在泌乳期,OXCT1基因在乳腺中表达量最高,在肾脏、垂体、脂肪、大脑、皮肤和肌肉中不表达;在非泌乳期,OXCT1基因在除脂肪以外的其他12个组织中都有表达。OXCT1基因在槟榔江水牛泌乳期乳腺组织中表达量最高,推测其可能参与了水牛的乳脂合成调控事件。本研究结果可为深入了解乳脂合成代谢及其调控机制提供依据。  相似文献   
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策勒黑羊选育现状及其对策   总被引:1,自引:1,他引:1  
策勒黑羊是以生产羔皮为主的多胎优良地方品种,深受当地群众的喜爱。作者从育种的角度阐述了策勒黑羊选育现状及存在的问题,提出了今后的选育方向和对策。  相似文献   
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The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders.  相似文献   
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8.

Salinity affects many areas in our country and around the world, resulting in dramatic reductions in plant yields. In this study, the plant yield, some plant quality parameters, and soil salinity in the plant root area were investigated by irrigating tobacco plants (Nicotiana tabacum L.) with different salinity irrigation waters. The experiment was carried out in pots in 4 replicates according to the randomized plot design. Six different salinity of irrigation water applications were applied in the experiment (S0?=?0.38 dS m?1, S1?=?2 dS m?1, S2?=?5 dS m?1, S3?=?8 dS m?1, S4?=?11 dS m?1, S5?=?15 dS m?1). According to the data obtained at the end of the research, as the salinity of irrigation water increased, plant length, leaf width, leaf length, leaf dry weight and leaf number decreased. It was determined that there was a certain increase in nicotine content in the face of the decrease of all examined physical parameters in irrigation water increase. In addition, the salinity values in the plant root zone soils and the salinity values in the outlet (drainage) water have also increased. Salinity threshold value of the tobacco plant was determined to be 2.04 dS m?1. With an increase in salinity by one unit, there was a 7.1% decrease in leaf dry weight. It was determined that the tobacco plant is vulnerable to salinity based on the data collected.

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9.
不同欧李品种(系)光合与水分利用特性比较   总被引:1,自引:0,他引:1  
以9种不同欧李品种(系)为试材,使用GFS3000光合测定系统测定了自然条件下叶片的光合和水分利用特性。结果表明:9种欧李品种(系)的净光合速率(Pn)、叶片气孔导度(Gs)、胞间CO2浓度(Ci)、蒸腾速率(Tr)、蒸腾比率(TR)、水分利用效率(WUE)均存在差异;在新疆生产建设兵团第十四师二二四团的生长环境下,Pn与Gs、Tr、WUE呈极显著正相关关系,而与Ci、TR呈极显著负相关关系;Ci与TR呈极显著正相关相关关系,与WUE呈极显著负相关关系;Gs与Tr呈极显著正相关关系,与TR呈显著负相关关系;Pn最高的"宏宇Ⅵ号"其WUE较高,但不是最高;WUE最高的"宏宇Ⅰ号"其Pn较高,但不是最高;"01-01号"的Pn和WUE均最低,其它品种(系)的Pn和WUE均处于中等水平,不同的欧李品种(系)通过不同方式协调自身的光合和水分利用来适应生长的环境。  相似文献   
10.
草地早熟禾的选育研究与利用   总被引:9,自引:0,他引:9  
内蒙古畜牧科学院草原所自 1985年以来 ,对从荷兰、美国、瑞典等国家引进的草地早熟禾 11个品种和国内采集的野生种进行了引种驯化 ,筛选出了瓦巴斯、凯达布鲁克茅 2个品种适应内蒙古地区的气候特点 ,是适宜推广种植的优良品种。利用国内野生种采用单株选择方法培育出了大青山草地早熟禾品种 ,它较原始群体抗性增强 ,叶量增加。目前已有较大的推广利用面积  相似文献   
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