Przewalskin A: A new C-23 terpenoid with a 6/6/7 carbon ring skeleton from Salvia przewalskii maxim

Przewalskin A (1), a novel C-23 terpenoid with a 6/6/7 carbon ring skeleton, was isolated from Salvia przewalskii. Its structure was determined by comprehensive 1D NMR, 2D NMR, and MS spectroscopic analysis and subsequently confirmed by a single-crystal X

南海北部湾23/25太阳区块海底工程地质调查与评价

<正> 本项成果,是承包美国太阳东方勘探公司任务而完成的。在系统分析总结了南海西部石油公司“南海—503工程地质取芯船”在南海北部湾23/25太阳区块所进行的测深、侧扫声纳、地震声学剖面测量,及4口孔深40米的工程地质浅钻土柱等材料的基础上,详细阐述了

Generation of 17-TW 23-fs pulses with a two-stage Ti : Sapphire amplifier at repetition rate 10 Hz

We have developed a two-stage Ti:sapphire amplifier system which can produce 17-TW/23-fs pulses at a repetition rate 10 MHz. A birefringent plate is used in the regenerative amplifier to alleviate gain narrowing, while an all-reflective cylindrical-mirror-based pulse stretcher and an acousto-optic programmable dispersive filter (AOPDF) are used to compensate for the higher order dispersion of the system.

秦岭苔类植物的研究和中国剪叶苔属（Herbertus S. Gray）的分类学修订

本论文包括两部分的内容，第一部分是秦岭苔类植物的区系研究，第二部分是中国剪叶苔属Herbertus的分类学修订。 秦岭位于我国的中部，东经104º30´～112º52´，北纬32º50´～34º45´N，约76 500 km2。它主要位于陕西省的南部地区，并包括了河南、甘肃和湖北的部分县、市。秦岭的最高峰是太白山，海拔3 767米。秦岭是长江和黄河的分水岭，也是我国温带和亚热带气候的过渡地带。 本研究包含了对自19世纪开始对秦岭苔藓植物的主要采集活动的回顾，和截止2008年以来对秦岭苔类和角苔类植物报道的总结和分析，且首次给出了一份秦岭地区详细的苔类植物的名录，并包括了各个种在秦岭地区的详细分布。根据目前的研究，现已知秦岭的苔类植物有226种（包括种下单位，以下同），其中角苔纲1科3属6种，苔纲30科59属220种；提出了1个新异名：Radula constricta Steph.被处理为Radula lindenbergiana Gottsche var. atypa Massalongo的异名；并提出了1个新组合Metzgeria pubescens var. kinabaluensis (Kuwah) F.X. Li & Y. Jia；发现秦岭新分布的苔类有78种。根据种数，秦岭地区苔类的优势科为光萼苔科（34种），其次为耳叶苔科（23种），裂叶苔科（23种）和羽苔科（19种）。 通过对这些种地理成分的统计，发现秦岭苔类的地理成分以北温带成分为主，占35.05%；其次是东亚成分占到31.78%，这两种地理成分在秦岭占了很大比例，高达66.83%。热带成分相对较少，有22种，占到10.29%。对于苔类来说，中国特有成分在秦岭地区较多，已知有34种，占到15.89%。说明秦岭地区苔类地理成分以温带为主，热带成分占少量比例，且秦岭地区的特有性也比较高。 文章第二部分是对中国剪叶苔属Herbertus S. Gray的分类学修订。剪叶苔属隶属于剪叶苔科，是一个古老而自然的类群，广泛分布于热带和南北温带地区。剪叶苔属植物由于其叶横生或近于横生，侧叶2裂，腹叶2裂或部分不对称3裂，并具假肋，叶细胞具大的三角体而明显区别于苔类的其它属。虽然这个属的概念比较清楚，但在属内种间的划分上存在较大的问题，是苔类中分类较混乱的一个类群。剪叶苔属种的概念多基于叶片形态，包括裂瓣的顶端细胞和假肋的形态及叶基盘边缘附属物的形态。但这些形态特征具很大的可塑性，性状不稳定，造成该属种的概念很模糊。目前全世界剪叶苔属约100余种。中国剪叶苔属的种类尚不确定，《中国苔藓志》中报道了中国有25种l亚种，但Juslen在2006年对亚洲剪叶苔属的修订中，提到中国分布的仅有6种。二者的研究中都存在有一些疏漏和不足之处，对有些种还有争议；且他们的研究中引证的标本都很少，不能全面反映中国剪叶苔属的种类和分布情况。 本研究着手于中国的剪叶苔属，从模式标本入手，从模式标本入手，结合对前人文献中引证标本的查阅，并检视了全国各大标本馆收藏的大量该属的普通标本，对于分类归并上有争议的种，采用扫描电镜和分子生物学的手段进行实验性的研究，对中国的剪叶苔属进行一个全面系统的分类学修订。期望通过本研究，明确中国剪叶苔属的种类和分布情况，为东亚乃至世界剪叶苔属的分类修订提供一份翔实的资料。共查阅了剪叶苔属26个种的模式标本，并检视了中科院北京植物研究所、华南植物园和深圳仙湖植物园馆藏的大量该属植物标本，约600余份。 通过本研究，提出2个新异名：将H. buchii Juslén和H. longispinus var calvs Massalongo处理为H. dicranus (Taylor) Trevis.；将樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.（原并入H. dicranus）和H. minimus Horik.（原并入H. dicranus）重新提出；发现1个中国新分布：H. setigerus (Steph.) H. A. Mill.；确认中国的剪叶苔属17种1亚种：剪叶苔H. aduncus (Dicks.) Gray，剪叶苔纤细亚种H. aduncus subsp. tenuis (A. Evans) H. A. Mill.et E. B. Bohrer，H. armitanus (Steph.) H. A. Mill.，南亚剪叶苔H. ceylanicus (Steph.) Abeyw.，长角剪叶苔H. dicranus (Taylor) Trevis.，高氏剪叶苔H. gaochienii Fu，广东剪叶苔H. guangdongii P.J. Lin & Piippo，卵叶剪叶苔H. herpocladioides Scott. et. Miller，红枝剪叶苔H. huerlimannii Miller，细指剪叶苔H. kurzii (Steph.) H. A. Mill.，长肋剪叶苔H. longifissus Steph.，长刺剪叶苔H. longispinus Jack et Steph.，H. minimus Horik.，长茎剪叶苔H. parisii (Steph.) H. A. Mill.，多枝剪叶苔H. ramosus (Steph.) H. A. Mill.，樱井剪叶苔H. sakuraii (Warnst.) S. Hatt.，短叶剪叶苔H. sendtneri (Nees) Lindb.和H. setigerus (Steph.) H. A. Mill.。本研究还在扫描电镜下观察了H. armitanus、长角剪叶苔H. dicranus和多枝剪叶苔H. ramosus的孢子形态。对于剪叶苔属的修订，还需要更多模式标本的借阅，随着研究深入，剪叶苔属的种类可能会有大量的减少，中国剪叶苔属的种类也将会有一定的减少。

黑麂Y染色体的鉴别和Sry基因的克隆及定位

以流式细胞仪分离小麂(Muntiacus reevesi)Y染色体和黑麂(M. crinifrons)Y_(1),Y_(2),X+4和1号染色体,利用DOP-PCR技术富集了分离的各单条染色体。然后,将小麂的Y染色体的DOP-PCR产物经Cy_(3)标记后直接作为涂染探针,应用染色体涂染技术与雌雄黑麂的核型标本进行杂交,确认了黑麂真正的Y染色体为Y_(2)染色体。再以黑麂的Y_(1),Y_(2),X+4和1号染色体的DOP-PCR产物为模板,用人的特异性的SRY基因引物对其进行扩增,结果表明黑麂只有Y_(2)染色体出现了SRY扩增片段。

Mapping chromosomal homologies between humans and two langurs (Semnopithecus francoisi and S-Phayrei) by chromosome painting

Chromosomal homologies were established between human and two Chinese langurs (Semnopithecus francoisi, 2n=44, and S. phayrei, 2n=44) by chromosome painting with chromosome-specific DNA probes of all human chromosomes except the Y. Both langur species showed identical hybridization patterns in addition to similar G-banding patterns. In total, 23 human chromosome-specific probes detected 30 homologous chromosome segments in a haploid langur genome. Except for human chromosomes 1, 2, 6, 16 and 19 probes, which each gave signals on two non-homologous langur chromosomes respectively, all other probes each hybridized to a single chromosome. The results indicate a high degree of conservation of chromosomal synteny between human and these two Chinese langurs. The human chromosome 2 probe painted the entire euchromatic regions of langur chromosomes 14 and 19. Human chromosome 1 probe hybridized to three regions on langur autosomes, one region on langur chromosome 4 and two regions on langur chromosome 5. Human 19 probe hybridized on the same pattern to one region on chromosome 4 and to two regions on langur chromosome 5, where it alternated with the human chromosome 1 probe. Human 6 and 16 probes both hybridized to one region on each of the two langur autosomes 15 and 18. Only two langur chromosomes (12 and 21) were each labelled by probes specific for two whole human chromosomes (14 and 15 and 21 and 22 respectively). Comparison of the hybridization patterns of human painting probes on these two langurs with the data on other Old World primates suggests that reciprocal and Robertsonian translocations as will as inversions could have occurred since the divergance of human and the langurs from a common ancestor. This comparison also indicates that Asian colobines are karyotypically more closely related to each other that to African colobines.

Dog chromosome-specific paints reveal evolutionary inter- and intrachromosomal rearrangements in the American mink and human

Forty chromosome-specific paint probes of the domestic dog (Canis familiaris, 2n = 78) were used to delineate conserved segments on metaphase chromosomes of the American mink (Mustela vison, 2n = 30) by fluorescence in situ hybridisation. Half of the 38 canine autosomal probes each painted one pair of homologous segments in a diploid mink metaphase, whereas the other 19 dog probes each painted from two to five pairs of discrete segments. In total, 38 canine autosomal paints highlighted 71 pairs of conserved segments in the mink. These painting results allow us to establish a complete comparative chromosome map between the American mink and domestic dog. This map demonstrates that extensive chromosome rearrangements differentiate the karyotypes of the dog and American mink. The 38 dog autosomes could be reconstructed from the 14 autosomes of the American mink through at least 47 fissions, 25 chromosome fusions, and six inversions. Furthermore, comparison of the current dog/mink map with the published human/dog map discloses 23 cryptic intrachromosomal rearrangements in 10 regions of conserved synteny in the human and American mink genomes and thus further refined the human/mink comparative genome map. Copyright (C) 2000 S. Karger AG, Basel.

Karyotypic relationships of horses and zebras: results of cross-species chromosome painting

Complete sets of chromosome-specific painting probes, derived from flow-sorted chromosomes of human (HSA), Equus caballus (ECA) and Equus burchelli (EBU) were used to delineate conserved chromosomal segments between human and Equits burchelli, and among four equid species, E. przewalskii (EPR), E. caballus, E. burchelli and E. zebra hartmannae (EZH) by cross-species chromosome painting. Genome-wide comparative maps between these species have been established. Twenty-two human autosomal probes revealed 48 conserved segments in E. burchelli. The adjacent segment combinations HSA3/21, 7/16p, 16q/19q, 14/15, 12/22 and 4/8, presumed ancestral syntenies for all eutherian mammals, were also found conserved in E. burchelli. The comparative maps of equids allow for the unequivocal characterization of chromosomal rearrangements that differentiate the karyotypes of these equid species. The karyotypes of E. przewalskii and E. caballus differ by one Robertsonian translocation (ECA5 = EPR23 + EPR24); numerous Robertsonian translocations and tandem fusions and several inversions account for the karyotypic differences between the horses and zebras. Our results shed new light on the karyotypic evolution of Equidae. Copyright (C) 2003 S. Karger AG, Basel.