Study of cellulolytic soil fungi and two nova species and new medium

This study is aimed at identifying and determining the percentage of occurrence frequency of cellulose decomposing soil fungi. The soil samples were inoculated into culture plates prepared in Sabouraud medium under sterilized conditions and incubated at 30 ℃ for 4 to 7 d. The identified fungal species were incubated in self-designed cellulose medium for testing their cellulolytic ability. Forty-two species, including2 nova species, representing sixteen genera showed growth and sporulation in the cellulose medium. Most of the isolated species were from genus Aspergillus and Penicillium. Aspergillus niger and Mucor hiemalis showed highest occurrence frequency （45% and 36% respectively）, as these species were collected from about 80% of soil samples. Being agar free and cheaper, the new fungal medium designed showed results equivalent to Sabouraud medium.     

同工酶技术在鸡球虫研究中的应用

本文就同工酶技术在鸡球虫种株鉴定、流行病学、遗传学研究以及耐药虫株检测等方面的应用作一阐述,并扼要分析了该技术在球虫学研究中的优缺点。     

泸溪白沙瓦乡人的语言态度与乡话的濒危

从泸溪白沙瓦乡人的语言价值观、语言忠诚度、学习和保护乡话的态度考察瓦乡人的语言态度,透视乡话濒危的现象,剖析乡话使用衰退的原因。     

宏门冲国家级阔叶林采种基地鸟类多样性研究初报

2003年9-10月对湖南省怀化市通道宏门冲国家级阔叶林采种基地森林鸟类多样性进行了初步研究。结果表明：基地森林鸟类共计20种，隶属4目、10科、12属。群落多样性因地型而异，即体现了较高的生物多样性保护价值，又反映了良好的生态保护效应。     

Cytocompatible cellulose nanofibers from invasive plant species Agave americana L. and Ricinus communis L.: a renewable green source of highly crystalline nanocellulose

In this study, the fibers of invasive species Agave americana L. and Ricinus communis L. were successfully used for the first time as new sources to produce cytocompatible and highly crystalline cellulose nanofibers. Cellulose nanofibers were obtained by two methods, based on either alkaline or acid hydrolysis. The morphology, chemical composition, and crystallinity of the obtained materials were characterized by scanning electron microscopy(SEM) together with energy-dispersive X-ray spectroscopy(EDX), dynamic light scattering(DLS), X-ray diffraction(XRD), and Fourier transform infrared(FTIR)spectroscopy. The crystallinity indexes(CIs) of the cellulose nanofibers extracted from A. americana and R. communis were very high(94.1% and 92.7%, respectively). Biological studies evaluating the cytotoxic effects of the prepared cellulose nanofibers on human embryonic kidney 293 T(HEK293 T) cells were also performed. The nanofibers obtained using the two different extraction methods were all shown to be cytocompatible in the concentration range assayed(i.e., 0-500 μg/mL). Our results showed that the nanocellulose extracted from A. americana and R. communis fibers has high potential as a new renewable green source of highly crystalline cellulose-based cytocompatible nanomaterials for biomedical applications.     

中国特有植物海南海桑的生物学特性及其保护

海南海桑(Sonneratia hainanensis KO，E．Y．Chen etW．Y．Chen)属于海桑科海桑属，为我国特有树种，仅天然分布于我国的海南岛，现正处在濒危状态．本比较系统地综述了海南海桑的生物学特性，包括其外部形态、内部结构、地理分布、生态学和群落特性以及海南海桑的系统位置．最后，章分析了可能引起海南海桑濒危的原因，并提出了几点保护措施．     

Comparative studies on phenotypic plasticity of two herbs, Changium smyrnioides and Anthriscus sylvestris

INTRODUCTION Changium smyrnioides Wolff, a monotypicspecies of family Umbellaceae, occurs only in anarrow zone in the middle to eastern part of theChangjiang (Yangtze) River Basin, China. As ahighly valued medicinal herb, the fleshy roots ofthis species are widely picked, and as its habitatsare being disturbed increasingly by land use, it hasbecome an endangered species (Qiu and Fu, 2001).Anthriscus sylvestris (L.) Hoffm belongs to thesame family; has similar morphology and life…     

黑龙江省鸡东国境动植物考察

作者于1989-1999年考察了完达山、鸡东四山林区动植物,对动植物种源和基因库开发提出了看法.     

譬侔援推及其规则

《墨经》中所论譬、侔、援、推是以"类同"为根据的类比推理,运用中遵守"异类不比"的基本规则.系统阐释四种推理的内涵、特征,可见我国先秦类比逻辑的基本架构.     

保护生物多样性和人类社会可持续发展战略

现代生物灭绝的主要原因是人类活动影响的结果。保护生物多样性对人类生存和可持续发展具有十分重要的意义。为了可持续发展,首先要提高人们保护生物多样性的意识,树立适度发展、适当妥协的思想。在完善保护生物多样性的政策、制定相关法律法规、加强国际合作的同时,应当加强对生物多样性持续利用的科学技术研究,确立合理的资源管理计划,防治环境污染。