徽州传统聚落景观基因识别及其分析

借助"景观基因"理念,可通过标志性建筑、民居特征、布局形态、主体性公共建筑、聚落装饰、参考性环境因子等六个识别性要素对徽州传统聚落景观特征进行识别,进而构建徽州民居景观基因要素识别系统。牌坊、宗祠、水口园林是构成徽州区域传统聚落景观的主体基因,功能地位最突出;马头墙、天井可作为其附着基因和徽派民居景观的主体基因,较前者功能地位居次;它们共同构成了徽州传统聚落景观的内在特质及其外在特征的形成机理,是徽州文化的主要载体。     

Do teacher characteristics matter? New results on the effects of teacher preparation on student achievement

Research fairly consistently demonstrates that teachers are an important measurable factor in student learning, yet few teacher characteristics are shown to be consistently related to student achievement. Using a state administrative dataset that matches individual students to their teachers over time, I find that math teachers’ undergraduate performance, as measured by GPA (overall, math, and math education) and course hours (math and math education), is predictive of 5th grade math achievement. The effects of the teacher characteristics are mediated by years of experience and vary according to student types.     

植物耐盐性的信号传导途径及基因工程进展

就近几年来植物耐盐方面的研究热点如植物耐盐信号传导途径及植物耐盐基因工程进展等方面作了综述。     

人类STR标记的研究进展

STR是由1～6个核苷酸的串联重复片段构成的,均匀分布于人类基因组中的简单重复序列,由于重复单位的重复次数在个体间呈高度变异性并且数量丰富、分布广且均匀、多态信息含量高、检测快速方便等特点,因此目前被广泛应用于人类基因定位、连锁分析、血缘关系鉴定、群体遗传学、系统发生树构建、遗传做图等方面.     

Study on pig growth hormone gene polymorphisms in western meat-type breeds and Chinese local breeds

Chinese Meishan and Jiangquhai pigs are two of the most prolific pigs in the world, but their growth rate is lower than that of Duroc, Landrace and Pietrain pigs. It is suggested that growth rate is regulated by growth hormone. The objective of the current study was to analyze the porcine growth hormone (pGH) gene polymorphisms based on the polymerase chain reaction restriction fragment-length polymorphism method (PCR-RFLP) for three western meat-type breeds (Duroc, Landrace and Pietrain) and two local Chinese pigs (Meishan and Jiangquhai). Five polymorphic restriction sites were detected with the ApaI, MspI, BspI and HhaI restriction enzymes in two amplified fragments (605 bp, -119 to +486; 506 bp, +206 to +711). Breed difference was found only in the 506 bp fragment. There was no difference in allelic frequencies of BspI and HhaI restriction sites among the five breeds (P>0.05). Landrace and Meishan pigs lacked allele G3 of MspI site. The allele G3 frequency of restriction MspI site of the 506 bp fragment in Pietrain pigs was higher than that in Duroc and Jianquhai pigs (P<0.001). For ApaI site, the Meishan pigs lacked allele G1; no difference was found in allelic frequencies among Pietrain, Duroc, Landrace and Jiangquhai pigs (P>0.05). This new and rapid PCR-RFLP typing method is an attractive tool for analysis of porcine growth hormone gene restriction sites. The differences in MspI and ApaI restriction sites may explain the growth difference between the foreign meat-type breeds above mentioned and local Chinese pigs.     

植物抗寒基因研究进展

低温是一种常见的非生物胁迫,是限制植物分布、降低作物产量及品质的重要原因之一,是农业生产中的一种严重的自然灾害。随着植物抗寒分子机理的不断深入研究,目前已经克隆了很多植物抗寒相关基因,可通过基因工程手段提高植物的抗寒性,对农业生产具有重要意义．本文综合概述了目前已克隆的重要植物抗寒基因的最新研究方向、进展及应用。     

白细胞介素18及其生物活性

白细胞介素18(IL-18)是新近发现的一种细胞因子，能诱导TH1细胞等产生IFN-r，GM-CSF等细胞因子及Fas配体，具有增强THI细胞和NK细胞的细胞毒作用等免疫调节功能，在抗病原微生物感染、抗肿瘤及抗超敏反映等方面具有潜在的应用前景，同时，它也是内毒素诱导的小鼠肝坏死性休克的关键因子。     

RNAi的研究及应用

RNA干扰（RNA interference,RNAi）是由双链RNA（double-stranded RNA,dsRNA）引发的转录后基因沉默机制．RNAi可以调节和关闭基因的表达,进而调控细胞的各种高级生命活动,是真核生物中普遍存在的抵抗病毒入侵、抑制转座子活动、调控基因表达的监控机制．目前RNAi的研究取得了很大进展,有可能为肿瘤基因治疗提供新策略．     

主体教育思想的内涵、特点及其运用

主体教育思想是一种充分发挥师生双方的主体性，特别是充分发挥学生的主体性的教育思想，有其丰富的内涵和特点。在教育教学过程中要落实学生的主体地位，将主体教育思想贯穿于素质教育之中，更好地提高学生的综合素质。