氟喹诺酮类抗生素及耐药基因污染控制的研究进展北大核心CSCD

氟喹诺酮类抗生素属于喹诺酮类抗生素,是一类人畜通用的抗生素。近年来,被广泛应用于人类和畜牧、水产等养殖业领域,然而其大量使用,造成在环境中的不断残留和累积,给自然环境和人类健康造成了较大威胁。现有研究表明,微生物降解是有效去除氟喹诺酮类抗生素残留污染的有效方法之一。本文总结和介绍了近年来氟喹诺酮类抗生素微生物降解单株菌和混合菌群、微生物降解酶、降解途径以及微生物降解氟喹诺酮类抗生素的实际应用,并对目前氟喹诺酮类抗生素微生物降解研究中存在的问题进行了分析,以及对未来氟喹诺酮类抗生素微生物降解研究的重点进行了探讨,以期为后续的研究提供参考。     

多环芳烃在土壤中的行为

多环芳烃（PAHs)在土壤中达到吸附平衡时存在“快”和“慢”两个吸附过程,植物能够从土壤中吸收低分子量的PAHs并向植物的地上部分迁移转化,但PAHs在植物体内主要的累积方式是植物地上部分的空气污染,微生物对PAHs的降解依然是去除PAHs的主要方式,主要通过微生物产生的酶的作用,本文详细分析了影响PAHs生物去除的各种因素。     

土壤中氟喹诺酮类药物残留的生态效应及归宿

氟喹诺酮类药物是人工合成的高效广谱抗菌药,对细菌的DNA螺旋酶具有选择性抑制作用,因其具有良好的药物动力学特性及治疗效果,临床应用非常广泛,但同时也引起环境污染.本文综述了氟喹诺酮类药物的理化特性及其对环境的影响,土壤中残留氟喹诺酮类药物的检测以及氟喹诺酮类药物污染土壤的生物修复.     

经验性治疗社区获得性肺炎中的疗效评价

目的 评价β-内酰胺类抗生素联合大环内酯类与单用氟喹诺酮类治疗社区获得性肺炎的疗效.方法 收集符合纳入及排除标准的2010年1月1日至2011年6月30日期间就诊于浙江大学医学院附属第一医院的社区获得性肺炎临床资料并进行分析.结果 有89例病例纳入本次研究,其中56例接受β-内酰胺类抗生素加大环内酯类,33例单用氟喹诺酮类治疗.两组患者在年龄,性别组成,合并症,入院前抗生素治疗,影响体温药物的应用,体征及部分实验室检查等方面差异均无统计学意义(P＞0.05).在临床疗效评价上,两组在入院后退热时间、住院时长及CRP下降80％时间差异均无统计学意义(P＞0.05),根据PSI进行亚组分析差异亦无统计学意义.结论 β-内酰胺类抗生素联合大环内酯类与单用氟喹诺酮类在治疗轻中度社区获得性肺炎时,二者疗效相当.     

植物修复多氯联苯研究进展

综述了植物修复持久性有机污染物多氯联苯（PCBs）的研究进展,重点阐述了植物对PCBs的去除作用和机理,植物在从环境中去除PCBs的过程中,不仅仅是作为微生物降解的支持者,而且还作为积极的参与者对PCBs进行代谢：一方面植物通过根系从环境中吸收和积累PCBs,并将吸收的PCBs转化为非毒性的代谢产物累积于植物组织中;另一方面植物释放促进PCBs降解的酶直接降解PCBs,或释放根系分泌物,增加根际微生物的数量,提高其活性间接降解PCBs.文中对植物修复PCBs的影响因素如植物组织培养的类型、生物量、PCBs的初始浓度以及PCBs的类型、理化性质等进行了讨论.     

土壤中氟喹诺酮类药物残留的生态效应及归宿

氟喹诺酮类药物是人工合成的高效广谱抗菌药, 对细菌的DNA螺旋酶具有选择性抑制作用, 因其具有良好的药物动力学特性及治疗效果, 临床应用非常广泛, 但同时也引起环境污染。本文综述了氟喹诺酮类药物的理化特性及其对环境的影响, 土壤中残留氟喹诺酮类药物的检测以及氟喹诺酮类药物污染土壤的生物修复。     

生物基因技术修复石油污染土壤研究进展

植物修复油污土壤是控制环境污染的有效途径,但在实际应用中存在着植物生物量较小、生长缓慢等不足。将具有修复功能的外源基因引入植物中,使转基因植物的生物修复功能大大增强,为解决土壤石油污染问题提供了有效手段。文章系统论述了转基因植物对石油污染土壤中有机污染物,尤其是对持久性有机污染物（POPs）的吸收、转化和降解作用以及近年来所取得的突破性进展,并指出了利用生物基因修复技术进行土壤石油污染研究的发展趋势。     

土壤氟形态与氟污染土壤修复

我国土壤氟污染问题严峻,给部分地区人体健康和生态安全造成严重威胁,但土壤氟污染与防治问题仍没有受到人们的广泛关注.本文概述了土壤中氟的存在形态以及发生的主要化学反应,综述了近年来国内外有关氟污染土壤修复的研究进展,提出了今后氟污染土壤修复的研究方向,以期为氟污染土壤的修复提供借鉴和参考.土壤中氟主要分为5种形态,其中90%以上以残渣态存在,土壤溶液中的氟主要发生沉淀-溶解、络合-解离和吸附-解吸等反应来维持水-土系统中的氟平衡.目前,氟污染土壤修复技术研究主要集中在化学固定修复技术、化学淋洗技术、电动修复技术以及植物修复技术.今后需要重点研究氟在土壤中的赋存形态及其影响因子,筛选功能微生物和植物,开发联合修复技术以修复氟污染土壤.     

转基因植物对有机污染物的吸收、转化和降解

有机污染物是土壤、水体和大气环境的重要污染物.利用和加强植物修复作用是控制环境污染的有效途径.近年来,一些具有修复功能的外源基因被陆续引入到植物中,使转基因植物的生物修复能力大大增强.文章介绍了植物对污染环境中有机污染物,尤其是持久性有机污染物(POPs)的吸收、转化和降解作用,阐述了转基因植物用于被污染环境修复方面的研究进展和应用前景.     

氟喹诺酮类抗生素心脏毒性机制的研究进展

氟喹诺酮类抗生素的心脏不良反应较为罕见,但产生的后果严重,所以倍受关注。本文从离子通道角度、动作电位水平和心电图表现等方面对氟喹诺酮类药物心脏毒性电生理机制的研究进展进行综述。     

Recent advances in the study of Kaposi's sarcoma-associated herpesvirus replication and pathogenesis

It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.     

The structure, reproduction and taxonomy of Vidalia and Osmundaria (Rhodophyta, Rhodomelaceae)

Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.     

New or rare chromosome counts in Artemisia L. (Asteraceae, Anthemideae) and related genera from Kazakhstan

Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.     

肝癌中HBV和HCV基因和抗原的分布及意义

采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细     

Selection with two alleles and complete dominance

For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.