Seed Dormancy,Germination and Storage Behavior of Magnolia wilsonii (Magnoliaceae), an Endangered Plant in China

In this paper, we measured the embryo morphology and size of Magnolia wilsonii seeds. And the effects of temperature, stratification, KNO3 and soaking on seed dormancy and germination were studied. Seeds were desiccated to different moisture content, and then stored at 4℃ and -20℃ for 100 d. The effects of desiccation and storage temperature on seed viability of M. wilsonii were analyzed. The results showed that the underdeveloped embryos of Mwilsonii seeds needed cold stratification to achieve physiological afterripening. The favorable temperature for germination of Mwilsonii seeds was 25/20℃. Cold stratification and GA3 could effectively overcome dormancy of Mwilsonii seeds. Therefore, Mwilsonii seeds have morphophysiological dormancy. About 5350% of seeds could survive in the moisture content of 539%. After 100 d storage at -20℃, all seeds in different moisture contents died. However, after 100 d storage at 4℃, 76% of seeds survived. Thus, Mwilsonii seeds exhibited intermediate seed storage behavior. The optimum storage environments was dry or moist storage at 4℃.     

中国和越南褐飞虱抗药性研究

2010年用稻茎浸渍法监测了我国和越南共14个褐飞虱Nilaparvata lugens(St(a)l)田间种群对5种杀虫剂的抗性,结果表明:14个褐飞虱田间种群对吡虫啉、噻嗪酮、氟虫腈、吡蚜酮和叶蝉散的LC50值分别在9.5287～46 6716、1.6621～17.8785、0.9818～ 8.4084、0.331...     

三倍体丹参杂交种的花粉形态研究

三倍体丹参是以二倍体丹参为父本、人工染色体加倍的四倍体白花丹参为母本杂交选育的杂交种。为深入了解三倍体丹参花粉的特性,以及为三倍体种质利用提供孢粉学依据,该文以二倍体丹参为对照,研究了三倍体丹参杂交种花粉的形态变异规律。利用光学显微镜和扫描电镜对二倍体和三倍体丹参的花粉萌发沟、外壁纹饰、花粉粒形状等特征进行了显微和超微形态观察,综合进行了花粉形态差异比较,并对花粉大小和形状数据进行了差异显著性分析和正态检验。结果表明:(1)二倍体丹参为6沟花粉,三倍体花粉萌发沟有6沟和8沟两种类型,沟内疣状颗粒分布不匀,出现畸形萌发沟。(2)二倍体和三倍体花粉外壁均为网状雕纹。二倍体花粉网眼内具多个多边形穿孔,穿孔大; 6沟和8沟两种类型的三倍体花粉网眼无穿孔或仅有几个小穿孔,6沟和8沟花粉的外壁雕纹相同。(3)三倍体花粉的极轴长(P)和赤道宽(E)均值显著小于二倍体花粉,花粉大小呈偏正态分布,P*E的差异系数大于二倍体花粉,且有极值存在。三倍体和二倍体丹参的萌发沟和雕纹存在差异,而花粉形状差异不显著。综上结果表明三倍体丹参花粉在倍性效应和杂合性的双重影响下发生了形态变异,且有多种形态变化。     

西双版纳传统利用的野生药食两用植物

2010年3月至2011年7月对西双版纳少数民族传统利用的药食两用植物进行民族植物学调查,通过访谈和野外调查工作,收集并记录了关于当地社区传统利用药食两用植物的传统知识以及其他相关信息,并选择了其中20种植物进行抗菌活性的筛选。共调查统计了43科95种西双版纳传统利用的药食两用植物,从分类学角度来看,以茄科（6种）和唇形科（6种）最多,其中草本植物占了最大比例,为49．5％。对其中20种植物的抗菌活性筛选结果显示,只有马蓝（Baphicacanthus cusia）和旋花茄（Sola-humspirale）对金黄色葡萄球菌有抑菌活性。从调查中可以看出：药食两用植物的利用在当地人的日常生活中仍占有相当重要的分量。但随着近年来经济快速发展导致的传统知识的急剧流失和森林的大面积砍伐,很多植物已经逐渐从人们的生活中淡出．如何保护这些传统知识并使其能够可持续发展下去是一个值得思考的问题。     

闭花耳草的化学成分研究

从闭花耳草(Hedyotis cryptantha )全草中分离得到11个化合物,经波谱数据分析鉴定为车叶草苷(1),车叶草苷酸(2),车叶草苷酸甲酯(3),车叶草酸乙酯(4),3,4-二氢-3-甲氧基车叶草苷(5),山奈酚(6),kaempferol 3,7-di-O -β-D-glucoside(7),kaempferol 3-O -β-D-galactopyranosyl-(1→3)-β-D-galactopyranoside(8),乌索酸(9),豆甾醇(10),β-谷甾醇(11)。所有化合物均为首次从闭花耳草植物中分离得到,其中化合物7和8首次从耳草属(Hedyotis )植物中分离得到。     

开花红哺鸡竹叶片的显微结构与光响应参数研究

为阐释竹子开花过程中的生理功能变化,探寻竹子花后复壮更新的途径,本研究选取红哺鸡竹(Phyllostachys iridescens)竹林换叶后出现开花征兆的竹株异形叶和外观正常叶,并以未开花竹株正常叶为对照,进行了叶片结构观察和光响应测定。结果发现:红哺鸡竹从营养生长向生殖生长转变的过程中,叶片的发育有变小变薄的特征,相邻维管束距离增大,维管束横切面积和气孔密度有显著变小的趋势(p0.05)。开花竹异形叶的叶片厚度、上表皮厚度、维管束横切面积和气孔密度是未开花竹正常叶的71.59%、87.40%、77.79%和73.56%,相邻维管束距离增加了19.34%,这种结构的变化相应地导致了开花竹叶片光合和蒸腾作用的显著降低(p0.05)。开花竹异形叶的光响应参数,如光饱和点、表观量子效率和最大光合速率是未开花竹正常叶的67%、40.5%和8.27%,分别为900、0.015、1.22μmol·m-2·s-1;光补偿点比未开花竹正常叶高出208.5%,达85.11μmol·m-2·s-1,而开花竹外观正常叶的光响应参数介于两者之间。开花竹株的叶片结构弱化和随之产生的生理功能异化可能是多年生竹子无法像树木那样连年开花、持续生长的重要原因之一。     

应用SELEX技术筛选人类血型IgG适体的实验研究

目的:建立Rh(D)血型的IgG类抗体适体的筛选方法,为后续合成适体并进行新生儿溶血病的防治研究奠定基础。方法:利用SELEX技术,构建含有52个随机序列的单链DNA文库,利用硝酸纤维素膜法筛选与IgG类抗体分子高亲和力结合的核酸分子,同时探索并优化将其扩增为双链DNA核酸库的PCR反应条件;通过膜结合实验检测核酸分子的富集效果并用凝胶阻滞实验初步测定所得核酸适体与Rh(D)血型IgG类抗体的亲和力。结果:随着筛选的进行,核酸分子的富集库向着与靶分子亲和性增强的方向进化,经过了11个循环,筛选出与Rh(D)血型IgG抗体结合力较强的核酸分子,与核酸结合的IgG分子在凝胶阻滞实验中显示出阻滞带。结论:初步建立了利用SELEX技术筛选人类Rh(D)血型IgG抗体适体的方法。     

阻生牙拔除术的临床进展

阻生牙是指由于各种阻力导致不能正常萌出的牙齿的统称,通常阻生牙牙体大部甚至全部埋伏于骨内。阻生牙可导致各种并发症的发生,因此临床上一般主张预防性拔除阻生牙。阻生牙拔除手术因其难度高、风险大、术后反应重一直是口腔牙槽外科关注的重点。近年来随着手术器械、手术观念等方面的进步,阻生牙拔除术取得了一些临床进展。新型CT扫描设备CBCT可以为手术设计提供精确定位;借助各类微创器械,微创拔牙技术减小了手术创伤,降低了手术风险;新型麻醉方式和新型局麻药物可以极大减轻疼痛反应;心理干预也将成为阻生牙拔除患者围手术期管理的重要步骤。本文对近年来阻生牙拔除术在定位方式、微创技术、团队协作、疼痛控制和心理干预等方面的临床进展做一综述。     

HAV病毒液的3种浓缩方法比较

目的:对HAV病毒液的3种常见浓缩方法进行分析比较,为HAV病毒研究及规模化疫苗生产提供参考。方法:使用MILLIPORE PELLICON超滤、PEG 6000沉淀、蔗糖-甘油垫三种方法对纯化HAV病毒液进行浓缩,用ELISA方法对浓缩液进行抗原滴度检测,计算不同浓缩方法的回收率。结果:HAV病毒液经过7次超滤循环浓缩,平均回收率为86%;PEG浓缩方法回收率平均72.5%;蔗糖-甘油离心浓缩方法平均回收率53.3%。结论:蔗糖/甘油超离心法,集纯化浓缩一体,适用于样品量较少,需要高浓度样品的试验;PEG浓缩得率适中,操作简单,应用范围较广;超滤膜浓缩在大规模疫苗生产或样品量较大时适用,但需控制样品浓度及浓缩倍数不能太高,以免样品损失。     

Retrospective Analysis of 234 Nasopharyngeal Carcinoma Patients with Distant Metastasis at Initial Diagnosis: Therapeutic Approaches and Prognostic Factors

Purpose

The purpose of this retrospective study was to identify the independent prognostic factors and optimize the treatment for nasopharyngeal carcinoma (NPC) patients with distant metastasis at initial diagnosis.

Methods

A total of 234 patients referred between January 2001 and December 2010 were retrospectively analyzed. Among the 234 patients, 94 patients received chemotherapy alone (CT), and 140 patients received chemoradiotherapy (CRT). Clinical features, laboratory parameters and treatment modality were examined with univariate and multivariate analyses.

Results

The median overall survival (OS) time was 22 months (range, 2-125 months), and the 1-year, 2-year, 3-year overall survival rates were 82.2%, 51.3% and 34.1%. The overall response and disease control rates of metastatic lesions after chemotherapy were 56.0% and 89.8%. The factors associated with poor response were karnofsky performance score (KPS) <80, liver metastasis, lactate dehydrogenase (LDH)>245 IU/L, and number of chemotherapy cycles <4. The 3-year OS of patients receiving CRT was higher than those receiving CT alone (48.2% vs. 12.4%, p<0.001). Subgroup analysis showed that significantly improved survival was also achieved by radiotherapy of the primary tumor in patients who achieved complete remission (CR)/partial remission (PR) or stable disease (SD) of metastatic lesions after chemotherapy. Significant independent prognostic factors of OS were KPS, liver metastasis, levels of LDH, and multiple metastases. Treatment modality, response to chemotherapy and chemotherapy cycles were also associated with OS.

Conclusion

A combination of radiotherapy and chemotherapy seems to have survival benefits for selected patients with distant metastases at initial diagnosis. Clinical and laboratory characteristics can help to guide treatment selection. Prospective randomized studies are needed to confirm the result.