中国人胃癌染色体17q21区域基因遗传不稳定性研究

To investigate microsatellite instability (MSI) and loss of heterozygosity (LOH) of locus D17S396, D17S579 and D17S855, and their effect on the expression of nm23H1 and BRCA1 of gastric cancer, which would provide experimental basis for clinical treatment and prognosis analysis of gastric cancer. DNA was extracted from paraffin-embedded materials. Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) was used to analyze MSI and LOH. Expression of nm23H, and BRCA1 was detected by Envision immuno-histochemistry and Leica-Qwin computer imaging techniques. In the forty cases of gastric cancer, the frequency of MSI, LOH and nm23H1 protein were 20.00%, 17.50% and 55.00% respectively at locus D17S396, while at locus D17S579, the frequency of MSI, LOH and BRCA1 protein were 22.50%, 15.00% and 37.50% respectively; at locus D17S855, the frequency of MSI, LOH and BRCA1 of thirty-seven cases were 18.92%, 18.92%, 37.84% respectively. In tumor node metastasis (TNM) staging, at locus D17S396, D17S579 and D17S855, MSI in stages I + II appeared more frequently than that in stages III + IV, while LOH appeared the contrary tendency. In the group of metastasis of gastric cancer, MSI had a less frequency (5.00%) than that with no metastasis (35.00%, P < 0.05) at locus D17S396, but LOH appeared more frequently (30.00%) than that with no metastasis (5.00%, P < 0.05). At locus D17S579, MSI had an increasing tendency with the degree of tumor differentiation (50.00% in high differentiation cases, 20.00% in middle differentiation cases, and 0% in low differentiation cases, P < 0.05). The frequency of nm23H1 and BRCA1 protein in stages TNM I + II was higher than that in stages TNM III + IV; and that in higher differentiation cases was higher than in poor differentiation cases. The frequency of nm23H1 protein in the group of metastasis (30.00%) was less than that with no metastasis significantly (80.00%, P<0.01). The frequency of nm23H1 protein in the group positive to MSI (87.50%) was higher than that in the group negative to MSI (46.88%, P < 0.05). However, nm23H1 protein in group positive to LOH (14.29%) was lower than that in the group negative to LOH (63.64%, P < 0.05). The frequency of BRCA1 protein in the group positive to MSI (66.67%) was more than that in the group negative to MSI (29.03%, P < 0.05). The results of experiments indicate that MSI and LOH may separately control the development of sporadic colon cancer with different pathways. MSI may be an early period molecule marker for sporadic colon cancer, enhanced expression of nm23H1 protein can effectively inhibit colon cancer metastasis and improve prognosis of sporadic colon cancer patients. By comparison, LOH mostly arises in the late period of sporadic colon cancer and endows a high aggressive and poor prognostic phenotype. nm23H1 protein could effectively restrain gastric cancer metastasis and development; and BRCA1 protein could restain tumor from becoming lower differentiation.     

聚集中国

藏族人为何适应高海拔低氧环境 为了研究藏族人群对于高海拔低氧地区的适应机制,科学家在海拔3200米以上的三个不同地区共收集了200多份藏族世居样品,     

自我保健与养生

联合国世界卫生组织（WHO）宣言：“健康不仅仅是不生病,而是身体上、心理上和社会适应上的完好状态。自我保健是个人、家庭、邻里、亲友间进行的卫生活动,是将医疗、预防、康复和保健合为一体的综合保健措施。健康的钥匙在自己的手中”。医学有两个目标,一是治病,二是防病。     

贵州四个山羊品种mtDNA多态性及起源分化

采用１５种限制性内切酶,研究贵州省４个山羊品种共９３只个体的线粒体ＤＮＡ多态性。其中ＢｏｍＨＩ、ＨｉｎｄⅢ和ＳａｌⅠ３种酶的酶切类型存在多态。共检测到１８种限制性态型,归结为３种ｍｔＤＮＡ单倍型。单倍型Ⅰ、Ⅱ在贵州山羊４个品种分布频率较高,分别为７７．４２％和２１．５０％,单倍型Ⅲ分布频率较低（１．０８％）;品种间亲缘关系聚类分析表明白山羊和黑山羊亲缘关系最近,其次为黔林羊,而与小香羊的亲缘关系最     

盐和水分预处理对扶芳藤幼苗抗寒性的影响

测定了扶芳藤新品种‘红脉’经不同方式预处理后对幼苗抗寒性的影响,测定了膜脂过氧化水平、保护酶活性和渗透调节物质含量的变化。结果表明,与对照低温胁迫相比,0.1和0.3mol/L NaCl溶液预处理后再经低温胁迫处理,扶芳藤幼苗的膜脂过氧化水平较低、保护酶活性高、渗透调节物质含量的累积较多,不同浓度的NaCl溶液预处理比不同浓度的PEG溶液预处理对提高扶芳藤的抗寒性更有效。通过实验证明了植物在不同的逆境中确实存在着交叉适应现象,植物对各种逆境胁迫有着许多相同的生理反应,对各种胁迫的适应性存在某些共同的机制。     

玛咖的愈伤组织诱导及植株再生

1植物名称玛咖(Lepidium meyenii). 2材料类别种子(秘鲁新世纪有限公司提供). 3培养条件以MS为基本培养基.愈伤组织诱导培养基:(1)MS 6-BA 0.5 mg·L-1(单位下同) NAA0.5;分化培养基:(2)MS 6-BA 4.0 NAA 0.5;生根培养基:(3)1/2MS NAA 0.5.以上培养基中均加入3%蔗糖、0.7%琼脂,pH 5.6～5.8.温度(25±2)℃,光照时间10～12 h·d-1,光照度为2000～2500 lx.     

光环境对胡桃楸幼苗生长与光合作用的影响

为了解胡桃楸幼苗对光的需求及适应规律,采用Li-6400便携式光合测定系统研究了不同光环境处理（100%、60%、30％和15%自然光）条件下3年生胡桃楸幼苗（适应1年后）叶片光合能力的季节变化及其对光强的响应.结果表明：在春季,胡桃楸幼苗对光反应不敏感,夏季和秋季随着光强的增加,叶片的最大光合速率、最大羧化速率和最大电子传递速率均显著增加（P<0.05）.光饱和点随光强的下降而降低（P<0.05）,表观量子效率、暗呼吸速率和光补偿点在不同光环境下未发现显著差异.100%和60%自然光处理的幼苗相对生长率差异不显著,但是随着光强下降,相对生长率显著下降（P<0.05）,为60%>30％>15%自然光处理.胡桃楸幼苗对不同的光环境表现出较强的适应性和可塑性;同时,通过降低光饱和点和减少碳积累,也能适应15%～30％自然光环境.     

90d模拟失重大鼠动脉压力反射反应性的改变

本工作研究了90d模拟失重大鼠动脉压力反射反应性的改变。即以血管活性药物变动平均动脉压(MAP),并同时记录反射性心率(HR)变化,采用非线性曲线拟合方法,定量评价清醒大鼠的动脉压力反射反应性的特征参数的改变。同时还利用受体阻断实验,观察迷走和交感神经成分在压力反射活动中的贡献。结果表明:模拟失重大鼠MAP-HR反应曲线向右上方移位,心率低限坪值升高,血压调节范围变窄,静态工作点升高。当心得安阻断β受体后,悬吊组大鼠压力感受性心率反射的平均增益及心率反应范围均高于对照组,提示模拟失重大鼠反射活动中迷走作用增强。     

《Molecular Plant》文章中文摘要

2012年第5卷第1期（http：//mplant.oxfordjournals.org/content/vol5/issue1/index.dtl）1Gutu A,Kehoe DM（2012）.Emerging perspectives on the mechanisms,regulation,and distribution of light color acclimation in Cyanobacteria.Mol Plant,5（1）：1～13题目：     

海南凤仙花不同海拔种群的传粉生物学

凤仙花属(Impatiens)植物具有极为广泛的多样性和类型各异的特化传粉者, 被誉为“双子叶的兰花”, 受到众多传粉生物学家的关注。本文以海南特有种海南凤仙花(Impatiens hainanensis)为研究对象, 对3个不同海拔梯度的种群进行了开花生物学特性和开花物候、花器官结构、花粉活力和柱头活性、传粉者种类和访花行为及繁育系统的比较研究。结果表明: 单花花期4.10 ± 0.46 d, 雄性期和雌性期分别约为3.15 ± 0.24 d和0.95 ± 0.36 d; 种群开花峰期在8月初, 高海拔种群的花期高峰相对滞后。低、中海拔种群花粉活力呈现先升高后下降的趋势, 以开花第2 d花粉活力最高; 高海拔种群花粉活力随开花时间推移逐渐下降; 柱头活性随开花时间的推移而增强, 高海拔种群开花各天次均较低、中海拔种群低。主要传粉昆虫为黄黑无垫蜂(Amegilla leptocoma)和绿条无垫蜂(A. zonata), 低、中海拔种群以黄黑无垫蜂为主, 高海拔种群以绿条无垫蜂为主。未观察到自动自花授粉和无融合生殖现象, 人工授粉能明显增加坐果率(75-90%), 自然坐果率在高海拔种群相对较低(40-60%), 说明存在较强的传粉者限制。海南凤仙花的保护需要同时关注其有效传粉者的保护, 促进有效传粉昆虫在不同海拔种群之间的往来, 保证种群间的花粉流与种子流, 维持海南凤仙花的种群遗传多样性与有效种群大小。