陕西根螨属一新种记述（蜱螨亚纲：粉螨科）

本文描述根螨属１新种：大蒜根螨Ｒｈｉｚｏｇｌｙｐｈｕｓ ａｌｌｉｉ ｓｐ．ｎｏｖ．,模式标本保存在西南农业大学植物保护系。     

Polymorphic Admixture Typing in Human Ethnic Populations

A panel of 257 RFLP loci was selected on the basis of high heterozygosity in Caucasian DNA surveys and equivalent spacing throughout the human genome. Probes from each locus were used in a Southern blot survey of allele frequency distribution for four human ethnic groups: Caucasian, African American, Asian (Chinese), and American Indian (Cheyenne). Nearly all RFLP loci were polymorphic in each group, albeit with a broad range of differing allele frequencies (δ). The distribution of frequency differences (δ values) was used for three purposes: (1) to provide estimates for genetic distance (differentiation) among these ethnic groups, (2) to revisit with a large data set the proportion of human genetic variation attributable to differentiation within ethnic groups, and (3) to identify loci with high δ values between recently admixed populations of use in mapping by admixture linkage disequilibrium (MALD). Although most markers display significant allele frequency differences between ethnic groups, the overall genetic distances between ethnic groups were small (.066–.098), and <10% of the measured overall molecular genetic diversity in these human samples can be attributed to “racial” differentiation. The median δ values for pairwise comparisons between groups fell between .15 and .20, permitting identification of highly informative RFLP loci for MALD disease association studies.     

钾对兰州百合鳞茎中多酚类物质积累代谢及其抗氧化活性的影响

为探究施钾对兰州百合鳞茎中多酚类物质的积累、抗氧化能力及差异代谢物的影响,该研究以兰州百合鳞茎为试材,通过固定氮素(N)和磷素(P)用量,设置不同钾(K)浓度处理,即K_(0)(不施肥)、K_(1)(447.6 mg·L^(-1))、K_(2)(671.4 mg·L^(-1))、K_(3)(895.2 mg·L^(-1)),采用福林-肖卡法、溴甲酚绿比色法、香草醛比色法、DPPH法、铜离子还原能力(CUPRAC)法测定不同K浓度处理下兰州百合鳞茎中多酚类物质含量及其抗氧化活性,并采用LC-MS法分析多酚类物质的差异代谢物,并进行差异代谢物筛选,功能注释及富集分析,为兰州百合的优质栽培提供理论依据。结果表明:(1)不同K浓度处理下兰州百合鳞茎中多酚类物质的含量及其抗氧化活性存在显著差异(P<0.05),与K_(0)相比,K_(1)、K_(2)、K_(3)均能促进鳞茎多酚类物质的积累及其抗氧化能力的提高,其中以K_(2)(671.4 mg·L^(-1))效果最佳。(2)相关性分析表明,兰州百合鳞茎多酚类物质含量与抗氧化活性指标呈极显著(P<0.01)相关关系,相关系数为0.451~0.959。(3)K_(0)、K_(2)浓度处理下兰州百合鳞茎中存在89种多酚类及相关化合物,其中52种相对含量显著上调,37种相对含量显著下调,且显著富集到黄酮类及苯丙类化合物生物合成的通路上。研究认为,兰州百合的最佳施钾量(671.4 mg·L^(-1))能有效促进鳞茎中多酚类物质的积累并提高其抗氧化能力。     

Paraquat ingestion and pulmonary injury.

Ventricular aneurysm is usually a complication of acute transmural myocardial infarction. The development of cardiac aneurysm represents a process of continued thinning and fibrosis of the necrotic tissue of the ventricular wall. Survival allows the development of a solid fibrous scar which of itself does not affect global ventricular function substantially. Hence, ventricular aneurysms can be present for up to 18 years without production of serious symptoms. The cases were reviewed of 45 patients in whom aneurysmectomy and myocardial revascularization were carried out. Surgical mortality was low (6.6 percent, 30 days); survival one year after operation was 76 percent, but at three years had fallen to 47 percent. Cause of late death was dominantly cardiac. In 19 patients post-operative study was done; although graft patency was observed in 98 percent, substantive improvement in ventricular performance was seen in a minority of patients. The outcome in patients with ventricular aneurysm is primarily related to the status of the residual myocardium and to the status of the vessels which supply it. The mechanism of clinical improvement after aneurysmectomy has not been clarified. However, the long-term results appear to be similar to those in patients with extensive myocardial infarction.     

不同生长调节剂及基质对越南粉苞茉莉扦插生根的影响

为探索越南粉苞茉莉(Jasminum dichotomum)扦插生根的影响因素,建立扦插繁育技术体系,以1年生越南粉苞茉莉枝条为插穗,采用L16(44)正交试验,探讨生长调节剂种类及其浓度、处理时间、基质种类对越南粉苞茉莉茎段扦插生根的影响,利用排队评分法和公式评分法对正交试验进行分析。结果表明,A2B3C3D2为试验的最优处理组合,即将插穗在250 mg·L-1 IBA和500 mg·L-1 NAA混合药剂中浸泡20 min后扦插于沙子上。     

五唇兰对PEG模拟的干旱胁迫响应研究

为了解干旱对五唇兰(Phalaenopsis pulcherrima)生长的影响,以聚乙二醇(PEG)溶液模拟干旱胁迫,对其叶片的光合色素、渗透调节物质和非结构碳水化合物(NSC)含量变化进行研究。结果表明,随着PEG浓度增加,五唇兰植株含水量和鲜质量逐渐下降,以PEG为13.75%～14.84%时最显著。PEG处理显著降低叶片的叶绿素a和b含量。随着植株含水量的降低,叶片可溶性蛋白、淀粉(St)含量均呈下降趋势,可溶性糖(SS)含量、NSC和SS/St均呈先升后降的趋势。因此,干旱胁迫会影响五唇兰植株的含水量和光合产物的积累;在较低程度干旱胁迫下,可溶性糖在抗旱响应中发挥主要作用;随着干旱胁迫程度加深,五唇兰的生理代谢受到严重影响。     

春兰ב寒香梅’试管开花诱导及其生理基础

以春兰×寒香梅杂交种(Cymbidium goeringii×Cymbidium ‘Han Xiang Mei’)为材料,MS+琼脂4 g·L-1+蔗糖20 g·L-1+椰汁100 mL·L-1为基础培养基,通过单因素试验,探讨细胞分裂素(TDZ/6-BA)和无机盐浓度(P、K)对其试管花诱导的影响,测定花芽诱导的蛋白质、可溶性总糖含量与超氧化物歧化酶(SOD)活性及激素水平(IAA、ABA)。结果表明,添加0.2 mg·L-1 TDZ和2 mg·L-1 6-BA的花芽诱导率最高,分别为14.33%和14.00%;无机盐浓度3P/3K和3P/5K的培养基花芽诱导率较高,分别达16.67%和11.33%;花芽诱导最佳培养基为MS(3P, 3K)+TDZ 0.2 mg·L-1+椰汁100 mL·L-1+琼脂 4 g·L-1+蔗糖20 g·L-1,花芽诱导率可达34%左右。生理生化指标检测显示,可溶性蛋白、可溶性总糖含量及SOD活性与花芽诱导率呈正相关;稳定的内源激素IAA和ABA含量对花芽诱导有一定的积极作用,含量过高对花芽诱导有抑制作用。