基于生态位模型的艾比湖鹅喉羚生境评价

明确物种生境空间分布格局及其与环境因素的关系,对了解该物种的生境需求和适宜生境空间分布至关重要。生境评价和预测是对物种进行有效保护的基础。以鹅喉羚(Gazella subgutturosa)为研究对象,以其重要栖息地新疆博州艾比湖国家级湿地自然保护区为研究区域,选取115个鹅喉羚分布点数据和23个环境变量因子,应用MAXENT模型分析其生境空间分布及主要影响因子,划分了鹅喉羚在研究区域的适宜生境,并对它的栖息地特征进行了分析。探讨了鹅猴羚生境选择与环境因子的关系。结果表明:气温日较差是影响鹅喉羚生境分布的主要环境因子。植被类型,坡度和最干月降水量对艾比湖鹅喉羚的生境选择影响不大。除了温度和降水在内的19项生物气候变量是鹅猴羚选择生境的重要因素之外,海拔和坡向等地形特征也影响鹅猴羚的生境选择性。鹅喉羚的高度适宜生境区主要分布在研究区域的北部和东部,中度及低度适宜生境区则分布于高度适宜生境区的边缘,而非适宜生境区主要集中在西部地区。研究不仅提供了鹅喉羚在艾比湖的实际分布状况及其栖息地特征,也为鹅喉羚在栖息地方面的研究,即鹅猴羚的栖息地选择和环境因子的关系方面提供了一个重要的依据。     

Aspergillus takadae,a novel heterothallic species of Aspergillus section Fumigati isolated from soil in China

Aspergillus takadae is characterized by its heterothallic reproduction, pale yellow cleistothecia, broadly lenticular ascospores with two short equatorial crests and smooth convex surfaces, and broadly ellipsoidal to ovate conidia with a smooth wall. The validation of these novel species is supported further by the analyses of the β-tubulin, calmodulin, actin, and RPB2 sequences. In addition, the phylogenetic tree and DDBJ accession numbers of all the species of Aspergillus section Fumigati are presented. We report on the crossing of A. takadae species and the result of crossing A. takadae with a closely related species, A. spathulatus.     

The correlation among molecular phylogenetics, morphological data, and growth temperature of the genus Emericella, and a new species

The species of the genus Emericella have been classified and identified on the basis of morphological features. However, the phylogenetic relationships in this genus have not been investigated. To clarify the relationships according to molecular phylogenetics, morphological characteristics, and growth temperature regimens in Emericella, multilocus sequencing analysis based on recent Aspergillus taxonomy was carried out. Various characteristic species formed individual clades, and maximum growth temperature reflected the phylogenetics. Emericella species exhibit various ascospore characteristics, although some species do not have distinct ascospore ornamentation. Species that have smooth-walled ascospores with two equatorial crests are polyphyletic. Here, Emericella pachycristata is described and illustrated as a new species. Its ascospores are similar to those of E. nidulans. These species produce smooth-walled ascospores, but the equatorial crests of E. pachycristata are thicker than those of E. nidulans. On the phylogenetic trees, E. pachycristata is closely related to E. rugulosa, which produces ascospores with ribbed convex surfaces. Thus, E. pachycristata is considered to be a new species both morphologically and phylogenetically.     

Identification of cardiac glycosides in fractions from Periploca forrestii by high-performance liquid chromatography/diode-array detection/electrospray ionization multi-stage tandem mass spectrometry and liquid chromatography/nuclear magnetic resonance

Cardiac glycosides are a class of naturally occurring compounds that are characterized by some interesting biological activities and are widely distributed in the plant kingdom and can also be found in some animals. There is an interest in the chemical characterization of these molecules due to their toxicity and their use in medicines. In the study reported here, a combination of electrospray ionization tandem mass spectrometry with high-performance liquid chromatography equipped with diode-array detector (HPLC-DAD/ESI-MSⁿ), and hyphenation to both liquid chromatography and nuclear magnetic resonance spectroscopy (HPLC/NMR) were utilized for the on-line analyses of cardiac glycosides from Periploca forrestii. The fragmentation patterns and ¹H NMR spectra of nine isolated cardiac glycosides were investigated; their fragmentation rules and ¹H NMR spectral characteristics were summarized and applied to the structural identification of similar constituents in fractions from P. forrestii. As a result, a total of nine trace cardiac glycosides were tentatively determined by analyses of accurate molecular masses, representative fragment ions and characteristic ¹H NMR signals provided by HPLC/high-resolution mass spectrometry (HRMS), HPLC-DAD/ESI-MSⁿ and HPLC/¹H NMR experiments, respectively. Of these, eight (2–9) are new compounds and one (1) is reported from P. forrestii for the first time. Results of the present study can benefit the rapid identification and targeted isolation of new cardiac glycosides from crude plant extracts.     

新疆杏仁抗突变作用的实验研究

目的:应用小鼠骨髓嗜多染红细胞(PCE)微核检测试验以探讨杏仁抗突变作用。方法:采用小鼠嗜多染红细胞和有核细胞-微核率(MCN‰)检测法,研究它潜在的抗突变性。结果:该结果能表明杏仁对两种阳性对照组分别诱发的较高微核率有明显降低作用,而且特殊环境下嗜多染红细胞比有核细胞具有较高的敏感性,差异均为非常显著(P<0.001)。结论:杏仁有抗突变,保护染色体损伤,促进DNA修复作用。此项研究抗突变性食物开发和医疗保健中具有重要实际意义。     

金属离子抗性衣藻品系的分离筛选及其鉴定

从乌鲁木齐南山土壤中分离得到62株绿藻,利用印迹法筛选对Cu2＋、Fe3＋、Zn2＋、Co2＋4种金属离子有抗性的藻株。结果发现XJU-3、XJU-28和XJU-36对0.1mmol·L-1 Co2＋有抗性;XJU-28对1mmol·L-1 Zn2＋和Fe3＋有抗性;而XJU-36仅对0.05mmol·L-1 Cu2＋有抗性。利用形态学特征和rDNA转录单元内间隔区（ITS1和TIS2,包括5.8S）序列对3株绿藻进行了分类学鉴定。依据形态特征,初步判断3株绿藻可能属于衣藻属（Chlamydomonas）。利用ITS（包括5.8S）序列构建系统进化树分析,结果表明,XJU-3、XJU-28与Chlamydomonas zebra的关系较近,XJU-36与Chlamydomonas petasua的关系较近。     

CYP1A1基因单核苷酸多态性与肺癌的相关性研究

目的:探讨代谢酶CYP1A1基因MspI位点多态性与新疆汉族人群肺癌遗传易感性之间的相关性.方法:应用聚合酶链式反应(PCR)-限制性片段长度多态性(RFLP)技术检测59例新疆汉族肺癌和84例新疆汉族健康人的CYP1A1基因MspI位点多态性分布频率,并分析了CYP1A1基因MspI位点多态性与新疆汉族人群肺癌遗传易感性和患者性别之间的相关性.结果:(1)CYP1A1基因MspI位点3种多态基因型分布频率在两组间比较差异有统计学意义(χ2=6.682,P=0.035),CC基因型在病例组的分布频率显著高于正常对照组.(2)携带突变CC基因型的个体较携带TT基因型的个体患肺癌的危险性增加(OR=3.759.95%CI=1.228-11.494,P=0.035).(3)男女肺癌患者的CYP1A1基因MspI位点基因型及等位基因频率的差异均无显著性(P>0.05).结论:(1)CC突变基因型可能是新疆汉族人群的肺癌易感因素.(2)CYP1A1基因MspI位点多态性可能与新疆汉族肺癌患者的性别无关.     

乌鲁木齐市小型兽类群落特征与分布格局初步研究

根据2002年7月的调查资料对乌鲁木齐市养禽场鼠类群落进行了研究。结果表明：该地区分布的鼠类可划分为2种群落,(1)褐家鼠 小家鼠群落;(2)小家鼠 灰仓鼠群落。同时对鼠类群落的多样性,均匀度等进行了初步研究。     

Glycosides and xanthine oxidase inhibitors from Conyza bonariensis

Fractionation of the xanthine oxidase inhibitory methanol extract of Conyza bonariensis afforded three glycosides, in addition to nine known compounds including amyrin, beta-sitostero1 daucosterol, syringic acid 3-hydroxy-5-methoxybenzoic acid, eugenol 4-O-glucopyranoside, and luteolin, apigenin and takakin 8-O-glucuronide. The structures of the glycosides were established by a combination of spectroscopic methods (IR, MS, 1H and 13C NMR, DEPT, COSY, HMQC and HMBC) as 4-hydroxypyridin-3-carboxylic acid 4-O-glucopyranoside, 8-hydroxy-6,7-dihydrolinalool 8-O-glucopyranoside and bonaroside [viz. 1,3,4,12-tetrahydroxy-2-(9-hexadecenoylamino)octadecane 1-O-glucopyranoside]. The in vitro enzyme assay showed that syringic acid and takakin 8-O-glucuronide displayed weak inhibitory activity against xanthine oxidase with IC50 values of 500+/-41 microM and 170+/-12 microM, respectively.