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1.
The rapid racerunner,Eremias velox,is a widely distributed lizard from the northern Caucasus across entire Central Asia eastward to China.It is increasingly common to accept E.velox as a species complex in its entire range.To date,published morphological and molecular systematic hypotheses of this complex are only partially congruent,and its taxonomic status and evolutionary history are still far from clear.The mitochondrial cytochrome b gene and12S rRNA sequences were used to evaluate the taxonomy of this complex,with particular attention to the phylogenetic placement of populations in northwestern China.Examination of the phylogenetic analyses recovers seven distinct,biogeographically discrete,and well-supported clades,revealing genetically identifiable populations corresponding to some previously morphology-defined subspecies.Chinese E.v.roborowskii appears to have split from other Central Asian rapid racerunner lizards well before differentiation occurred among the latter taxa.Specifically,we corroborate that there are two subspecies occurring in China,i.e.,E.v.velox and E.v.roborowskii.We recommend a novel subspecific status for the phenotypically and genetically distinct populations in southern Aral Sea region of Uzbekistan previously assigned to E.v.velox.Finally,each of the three independently evolving lineages from Iranian Plateau should be recognized as three species new to science under the general lineage concept.  相似文献   

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The confusion of Huma (胡麻) in Chinese history was discussed after an introduction of Chih Wu Ming Shi T’u K’ao of the Qing Dynasty and its author—Wu Qijun’s contribution to Chinese botany. The morphological characters and distribution of Huma and Jusheng (巨胜) documented in ancient Chinese literature were comparatively studied. Simultaneously, other questions about the Chinese medicament and medicine were inspected in the backgrounds of historical development and social stratum differentiation. We concluded that the earliest recorded Huma in Chinese literature should be Linum usitatissimum. The Chinese name for this plant has been used by the folks until well into modern times. Jusheng (巨胜) should be Sesamum indicum. The reason for the confusion of these two names was also explored. It was further inferred that the confusion of names for traditional Chinese medicine (TCM) originated in the similarity of their property and function while the difference of their morphology and distribution was not taken seriously. We also concluded that Shên Nung Pên Ts’ao Ching was forged by TAO Hongjing (陶弘景) in his Collected Commentaries on Pên Ts’ao Ching but attributed to an ancient author, Shennong (神农). In this book TCM was classified by their property and function, which became the root cause of the confusion of Chinese names for TCM from then on. Some suggestions were also given for the development of Chinese materia medica in the future.  相似文献   

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孙悦华  毕中霖 《动物学报》2003,49(3):389-392
Based on two specimens collected from Sichuan Province, Yang et al. (1989) described a new subspecies of the spotted little owl (Athene brama), the belly-mottled little owl (Athene brama poikila). This subspecies has been acknowledged by Cheng (2000). However, Cheng (2000) also mentioned that further work should be done on this subspecies. In 2001, we checked the specimen of Athene brama poikila in Ya’an, Sichuan and comparing them with the spotted little owl and the boreal owl (Aegolius funereus). The boreal owl is identifiable from its rather square facial disc, however, this character was destroyed during the facture for these two specimens of Athene brama poikila. That is the reason Yang et al.(1989) missed them with the genus Athene. The genus Aegolius is also identifiable from the genus Athene from the character on the toes, as the toes of the boreal owl are covered with thick feathers, whereas the toes of the little owl are bristled. The toes of these two specimens of Athene brama poikila are thickly feathered, corresponding to the identification of the genus Aegolius. The morphological characters and measurements of the two specimens also correspond to the boreal owl. The habitat of the two specimens was reported as conifer deciduous forest around 2 200 m to 3 100 m, which fits the habitat of the boreal owl. The distribution of the endemic Gansu subspecies of the boreal owl (A. f. beickianus) was reported at Tiantangsi, Lianhuashan in Gansu, Guinan in Qinghai and Jiuzhaigou in Sichuan in China, it was also reported at Lahul in north India, Sun et al. (2001) suggested that it is probably the boreal owl is also distributed in the conifer forest of west Sichuan and east Tibet. The new distribution point in Baoxing and Yajiang in Sichuan corresponds to this conjecture. As a conclusion, we believe that these two specimens should belong to the A. f. beickianus of the boreal owl .  相似文献   

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Sequence-based molecular phylogenies have provided new models of early eukaryotic evolution. This includes the widely accepted hypothesis that animals are related most closely to fungi, and that the two should be grouped together as the Opisthokonta. Although most published phylogenies have supported an opisthokont relationship, a number of genes contain a tree-building signal that clusters animal and green plant sequences, to the exclusion of fungi. The alternative tree-building signal is especially intriguing in light of emerging data from genomic and proteomic studies that indicate striking and potentially synapomorphic similarities between plants and animals. This paper reviews these new lines of evidence, which have yet to be incorporated into models of broad scale eukaryotic evolution.  相似文献   

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<正>Phylogeography has been one major focus of evolutionary biology in recent years,with many important advances in Chinese species.In this issue,we collected 11 phylogeographic studies of plants by Chinese laboratories. We further synthesized the main findings and patterns emerging from these and previous phylogeographic studies in China and asked where phylogeographic research should be directed in the coming years.Numerous examples have shown that phylogeographic patterns in China did not show an expected expansion-contraction pattern at large scale, mirroring the geological records showing that no unified ice sheet had developed in China during the Quaternary Period.Instead,regional expansions and intraspecific divergences are very common in most studied species during the Quaternary oscillations.Different intraspecific lineages or alleles(haplotypes) were detected in multiple localized refugia,from where regional or local expansions are likely to have started.Hybridizations and introgressions are frequent between intraspecific lineages or between different species.We also reviewed computational methods for phylogeographic analyses.Despite the great progress made in recent years,there remains much to discover about the spatial-temporal dimensions and underlying speciation mechanisms of Chinese plants.Phylogeographic studies represent a key knot that connects the genus phylogeny(macroevolution) and speciation and adaptation (microevolution).Therefore,we advocate that:(i) phylogeographic studies of plants in China should be directed to the closely related species or a monophyletic group(for example,a genus or a section) in the coming years;and (ii) population genetic data based on direct sequencing multiple loci,especially those from nuclear genome and statistical tests should be widely adopted and enforced.The recovered intraspecific divergences and phylogeographic patterns of multiple-species may allow us to better understand the high plant diversity in China and set up concrete hypotheses for studying plant speciation and diversification mechanisms in this region.  相似文献   

6.
The Bowman-Birk inhibitors (BBIs) are well-studied serine protease inhibitors that are abundant in dicotyledonous and monocotyledonous plants. BBIs from dicots usually have a molecular weight of 8k and are double-headed with two reactive sites, whereas those from monocots can be divided into two classes, one approximately 8 kDa in size with one reactive site (another reactive site was lost) and the other approximately 16 kDa in size with two reactive sites. The reactive site is located at unique exposed surfaces formed by a disulfide-linked β-sheet loop that is highly conserved, rigid and mostly composed of nine residues. The structural features and molecular evolution of inhibitors are described, focusing on the conserved disulfide bridges. The sunflower trypsin inhibitor-1 (SFTI-1), with 14 amino acid residues, is a recently discovered bicyclic inhibitor, and is the most small and potent naturally occurring Bowman-Birk inhibitor.Recently, BBIs have become a hot topic because of their potential applications. BBIs are now used for defense against pathogens and insects in transgenic plants, which has advantages over using toxic and polluting insecticides. BBIs could also be applied in the prevention of cancer, Dengue fever, and inflammatory and allergic disorders, because of their inhibitory activity with respect to the serine proteases that play apivotal role in the development and pathogenesis of these diseases. The canonical nine-residue loop of BBIs/STH-1 provides an ideal template for drug design of specific inhibitors to target their respective proteases.  相似文献   

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Based on two specimens collected from Sichuan Province,Yang et al.(1989) described a new subspecies of the spotted little owl(Athene brama),the belly-mottled littlc owl(Athene brama poikila).This subspecies has been asknowledged by Cheng(2000),However,Cheng(2000)also mentioned that further work should be done on this subspotted little owl and the boreal owl(Aegolius funereus).The boreal owl is identifiable from its rather square facial disc,however,this character was destroyed during the facture for these two speciments of Athene brama poikila.That is the reason Yang et al.(1989) missed them with the genus Athene.The genus Aegolius is also identifiable from the genus Athene from the character on the toes,as the toes of the boreal owl are covered with thick feathers.whereas the toes of the little owl are bristled.The toes of these two specimens of Athene brama poikila are thickly feathred,corresponding to the identification of the genus Aegalius.The morphological characters and measurements of the two specimens also correspond to the boreal owl.The habitat of the two specimens was reported as conifer deciduous forest around 2200 m to 3100m,which fits the habitat of boreal owl.The distribution of the endemjic Gansu subspecies of the boreal owl(A.f.beickianus)was reported at Tiantangsi,Lianhuashan in Gansu,Guinan in Qinghai and Jiuzhaigou in Sichuan in China,It was also reported at Lahul in north India,Sun et al.(2001) suggested that it is probably the boreal owl is also distributed in the conifer forest of west Sichuan and east Tibet.the new distribution point in Baoxing and Yajiang in Sichuan corresponds to this conjecturc.As a conclusion,we believe that thest two spccimens should belong to the A.f.beickianus of the borcal owl.  相似文献   

8.
Ganoderma lucidum (Leyss. ex Fr.) Karst., a medicinal fungus called “Lingzhi” in China, has been used in traditional Chinese medicine in China for the prevention and treatment of various types of diseases, such as cancer, hepatopathy, arthritis, hypertension, neurasthenia, and chronic hepatitis. It is clear that the anticancer activity of G. lucidum is mainly due to polysaccharides and/or triterpenoids of the fungus. However, until now, the mechanism of the anticancer action of G. lucidum has not been well understood and, previously, the activation of the immune response of the host was widely considered to be the only mechanism by which G. lucidum prevented and/or treated cancer. However, recent studies reviewed in the present paper have shown that the potential mechanisms of anticancer action include not only the activation of the immune response of the host, but also the induction of cell differentiation, the induction of Phase Ⅱ-metabolizing enzymes, the inhibition of angiogenesis, and the inhibition of the expression of the urokinase-type plasminogen activator (uPA) and the uPA receptor in cancer cells. To further elucidate the mechanisms of action of G. lucidum, more in vivo tests and randomized controlled clinical trials should be carried out, and the molecular mechanisms should be studied intensively. Additionally, whether the anticancer compounds in G. lucidum act synergistically or independently should be further studied.  相似文献   

9.
D-glyceraldehyde-3-phosphate dehydrogenase (holo-GAPDH) from Palinurus versicolor was crystallized in a novel crystal form by the method of sitting-drop vapor diffusion. The crystals have space group P4212, cell parameters a=15.49 nm, c=8.03 nm and two subunits per asymmetric unit. The crystal structure at 0.34 nm was determined by the molecular replacement method. The final model has crystallographic Rfree and R factors of 0.274 and 0.262, and r.m.s. deviations of 0.002 nm for bond lengths and 2.33?for bond angles. The two subunits in asymmetric unit are similar to each other not only in the three-dimensional structure, but also in average temperature factors. This result demonstrates that the obvious difference in average temperature factors for the different subunits in C2 crystal form reported previously may be attributed to the different crystallographic environments of the subunits. This further supports that holo-GAPDH has a good 222 molecular symmetry.  相似文献   

10.
Classification of the Asian snake genera Lycodon and Oligodon has proven challenging. We conducted a molecular phylogenetic analysis to estimate the phylogenetic relationships in the genus of Lycodon and clarify the taxonomic status of Oligodon multizonatum using mitochondrial(cyt b, ND4) and nuclear(c-mos) genes. Phylogenetic trees estimated using Maximum Likelihood and Bayesian Inference indicated that O. multizonatum is actually a species of Lycodon. Comparing morphological data from O. multizonatum and its closest relatives also supported this conclusion. Our results imply that a thorough review of the evolutionary relationships in the genus of Lycodon is strong suggested.  相似文献   

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Birefringence of flow of preparations of myosin   总被引:4,自引:0,他引:4  
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A sensitive method for the detection of small quantities of hydrophobic antioxidant free radical scavengers such as butylatedhydroxytoluene (BHT) and butylatedhydroxyanisole (BHA) in aqueous samples is described. The procedure involves extraction of the hydrophobic free radical scavenger into an organic solvent phase, followed by the subsequent reaction of an aliquot of this extract with the stable cation radical tris(p-bromophenyl)amminium hexachloroantimonate (TBACA). In experiments with BHT and BHA, the loss of TBACA absorbance at 730 nm was found to be linearly proportional to the amount of antioxidant added, with quantities of BHT as small as 200 pmol being easily detectable. In aqueous suspensions of dimyristoylphosphatidylcholine vesicles, assays of the aqueous BHT concentration showed that BHT partitioned strongly into the membrane phase, achieving very high BHT/phospholipid ratios. For a given concentration of BHT, partitioning into the membrane phase was greater in large, multilamellar liposomes than in either small, single-walled vesicles or in purified rat brain synaptic vesicle membranes. Direct assay of BHT and BHA in phospholipid membranes, however, was complicated by a nonspecific interaction between TBACA and the phospholipid.  相似文献   

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通过对6种藓类植物,即褶叶青藓(Brachythecium salebrosum(Web.et Mohr.)B.S.G.)、湿地匐灯藓(Plagiomnium acutum(Lindb.)Kop.)、侧枝匐灯藓(Plagiomnium maximoviczii(Lindb.)Kop.)、大凤尾藓(Fissidensnobilis Griff.)、大羽藓(Thuidium cymbifolium(Doz.et Molk.)B.S.G.)和大灰藓(Hypnum plumaeforme Wils.)嫩茎和老茎的石蜡切片和显微观察发现,同一藓类植株的嫩茎和老茎,茎结构稳定,不同种藓类植物茎横切面具有不同特征.植物体茎横切面形状、表层细胞的层数、细胞大小和细胞壁厚薄、皮层细胞大小和形状、中轴的有无以及比例等特征可以作为藓类植物的分科分类依据之一.  相似文献   

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