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1.
朱允中  秦龙  郭柏炯  孟荟 《遗传》1985,7(4):31-32
最常见的人类x染色体的结构异常是长臂 等臂X染色体,以及X染色体与常染色体之间 的易位。关于idic(X)染色体结构异常的病例 较为罕见。国外Chapell:等曾有研究1,国内 周氏等w首次报道了有关idic(X)染色体结构 异常的病例。 1983年我们在一例Turner综合征发现其 外周血淋巴细胞核型具有双着丝粒X染色体, 为45,X/46,X, idic(X)/47,x, idic(X),idic (X)嵌合体核型,现报告如下  相似文献   

2.
Anaphalis yangii Y. L. Chen&Y. L. Lin,a new species of Compositae from Gongbo’gyamda County,Xizang,is described and illustrated. The new species is quite similar to A. spodiophylla Ling & Y. L. Chen,but can be easily distinguished by its thicker,bro  相似文献   

3.
A new species of the genus Gagea Salisb(Liliaceae)from Helanshan,Nei Mongol,China,G. alashanica Y. Z. Zhao & L. Q. Zhao,is described and illustrated. The new species is similar to G. neopopovii Goloskokov in the stigma capitate,tunic elongated upwards at  相似文献   

4.
Bolboschoenus (Ascherson) Palla (Cyperaceae) from Pliocene of China   总被引:1,自引:0,他引:1  
Tubers, culms, rhizomes, and leaves of Bolboschoenus cf. yagara (Ohwi) YC Yang et M Zhan were reported from the sediments of Zhangcun Formation, Late Pliocene in Shanxi Province, China. The fossil species possesses trigonous culms. And tubers are cordiform, spindle shaped, or round, and are covered by roots in internodes and often connected by rhizomes. This is the first convincing fossil record of Cyperaceae in China.  相似文献   

5.
StructuralAnalysisofrbcLGenefromanEndangeredPlant,(Acanthopanaxbrachypus)YANHua-jun(严华军);ZHUCheng(朱);WUNai-hu(吴乃虎)(Instituteo...  相似文献   

6.
After examining a large number of type and authoritative specimens of Schizophragma Siebold & Zucc., S. elliptifolium C. F. Wei and S. integrifolium var. glaucescens Rehder were reduced to synonyms of S. hypoglaucum Rehder and S. integrifolium f. cordatum S. Y. Wang was reduced to synonym of S. corylifolium Chun. Schizophragma crassum var. ellipticum J. Anthony was treated as the correct name of S. crassum var. hsitaoanum (Chun) C. F. Wei. The name S. integrifolium var. minus Rehder is reinstated. The taxonomic treatment is supported by leaf epidermal characters.  相似文献   

7.
Floral morphogenesis and the development of Cercidiphyllumjaponicum Sieb. et Zucc. were observed by scanning electron microscopy (SEM). The results showed that the pistillate inflorescences were congested spikes with the flowers arranged opposite. Great differences between the so-called "bract" and the vegetative leaf were observed both in morphogenesis and morphology. In morphogenesis, the "bract" primordium is crescent-shaped, truncated at the apex and not conduplicate, has no stipule primordium at the base but does have some inconspicuous teeth in the margin that are not glandular. The leaf primordium is triangular, cycloidal at the apex, conduplicate, has two stipule primordia at the base, has one gland-tooth at the apex occurring at first and some gland-teeth in the margin that occur later. In morphology, the "bract" is also different to the vegetative leaf in some characteristics that were also illustrated in the present paper. Based on the hypothesis that the bract is more similar to the vegetative leaf than the tepal, we considered that the so-called "bract" of C.japonicum might be the tepal of the pistillate flower in morphological nature. Therefore, each pistillate flower contains a tepal and a carpel. We did not find any trace of other floral organs in the morphogenesis of the pistillate flower. Therefore we considered that the unicarpellate status of extant Cercidiphyllum might be to highly reduce and advance characteristics that make the extant Cercidiphyllum isolated from both fossil Cercidiphyllum-like plants and its extant affinities.  相似文献   

8.
Cladistic analysis of the morphological relationship of40populations of Paeonia sect.Moutan DC.(including all wild species)was carried out with an attempt to have a better understanding of the phylogeny of tree peonies.Twenty-five morphological characters  相似文献   

9.
XingL XiaGH 《Cell research》2001,11(2):116-124
Gal alpha(1, 3) Gal (gal epitope) is a carbohydrate epitope and synthesized in large amount by alpha(1, 3) galactosyltransferase [alpha(1, 3) GT] enzyme on the cells of lower mammalian animals such as pigs and mice. Human has no gal epitope due to the inactivation of alpha(1, 3) GT gene but produces a large amount of antibodies (anti-Gal) which recognize Gal alpha(1, 3) Gal structures specifically. In this study, a replication-deficient recombinant adenoviral vector Ad5sGT containing pig alpha(1, 3) GT cDNA was constructed and characterized. Adenoviral vector-mediated transfer of pig alpha(1, 3) GT gene into human tumor cells such as malignant melanoma A375, stomach cancer SGC-7901, and lung cancer SPC-A-1 was reported for the first time. Results showed that Gal epitope did not increase the sensitivity of human tumor cells to human complement-mediated lysis, although human complement activation and the binding of human IgG and IgM natural antibodies to human tumor cells were enhanced significantly after Ad5sGT transduction. Appearance of gal epitope on the human tumor cells changed the expression of cell surface carbohydrates reacting with Ulex europaeus I (UEA I) lectins, Vicia villosa agglutinin (VVA), Arachis hypogaea agglutinin (PNA), and Glycine max agglutinin (SBA) to different degrees. In addition, no effect of gal epitope on the growth in vitro of human tumor cells was observed in MTT assay.  相似文献   

10.
YearEvent and Theoretieal Implieation/ExtensionReferenee1865Gregor Mendel establishes the laws of segregation and Mendel,G.1865.Versuehe位berindePendent assortment.Pflanzenhybriden.Ve从.刃dtorforseh. Ver.Br戎nn 4:3一47.1866Ernst HeinrichH盆ckel坤potheses that the nueleusof a eell transmits its hereditary information.1867VVllhelm Friedrieh Benediet Hofilieister estab-lishes the regularity of the“dissolution,,of the nueleusprior to division of the maternal eell,and the aPPear-anee of n…  相似文献   

11.
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13.
Frederick Sanger (1980 Noble Prize Laureates for Chemistry) explores the technology of DNA sequencing. Sanger and colleagues use the technique to determine the sequence of all 5,375 nucleotides of the bacteriophage phi-X174, the first completede termination of the genome of an organism.  相似文献   

14.
《现代生物医学进展》2007,7(12):I0001-I0004
PCR是80年代中期发展起来的体外核酸扩增技术。它具有特异、敏感、产率高、快速、简便、重复性好、易自动化等突出的优点;能在一个试管内将所要研究的目的基因或某一DNA片段于数小时内扩增至十万乃至百万倍,使肉眼能直接观察和判断;可从一根毛发、一滴血、甚至一个细胞中扩增出足量的DNA供分析研究和检测鉴定。过去几天几星期才能做到的事情,用PCR几小时便可完成。PCR技术是生物医学领域中的一项革命性创举和里程碑。  相似文献   

15.
16.
Based on Podocarpium lancangense Y.Y.Qian,a new combination,Hylodesmum lan-cangense(Y.Y.Qian)X.Y.Zhu&H.Ohashi,is proposed.  相似文献   

17.
Protocorm-like bodies (PLBs) or thin cell layers (TCLs) derived from PLBs of hybrid Cymbidium Twilight Moon 'Day Light' can induce new or neo-PLBs on Teixeira Cymbidium (TC) medium, which contains 0.1 mg/L a- naphthaleneacetic acid, 0.1 mg/L kinetin, 2 g/L tryptone and 20 g/L sucrose, and is solidified with 8 g/L Bacto agar. This study aimed to assess the response ofneo-PLB formation to an ethylene-liberating compound (2-chloroethylphosphonic acid (CEPA)), to two ethylene inhibitors (silver nitrate (AgNO3) and aminoethoxyvinylglycine (AVG)), and to aeration (made possible by using Milliseal~ or autoclaved filter paper). AgNO3 at 1 or 2 mg/L in TC medium significantly increased the fresh weight of PLBs while 1 mg/L of AgNO3 also showed a significant increase in the number ofneo-PLB from both half-PLBs and from tTCLs. In contrast, AVG and CEPA inhibited neo-PLB formation. Neo-PLB formation from half-PLB or TCL explants in the presence of aeration resulted in significantly lower neo-PLB weight. The use of AgNO3 and aeration are alternative means to mass produce neo-PLBs for micropropagation purposes.  相似文献   

18.
Abstract The karyomorphology of three species in Dipentodon (Dipentodontaceae), Perrottetia (Celastraceae), and Tapiscia (Tapisciaceae), namely Dipentodon sinicus, Perrottetia racemosa, and Tapiscia sinensis, was investigated in the present study. Recent molecular research has discovered close relationships among these three genera, which has led to the establishment of the order Huerteales with Perrottetia being placed in Dipentodontaceae. Herein we report the chromosome numbers of D. sinicus and P. racemosa for the first time, and present their karyotype formulas as 2n = 34 = 22 sm + 12 st (D. sinicus), 2n = 20 = 11 m + 9 sm (P. racemosa), and 2n = 30 = 22 m(2SAT) + 8sm (T. sinensis). Asymmetry of their karyotypes is categorized to be Type 3B in D. sinicus, Type 2A in P. racemosa, and Type 2A in T. sinensis. Each of the species shows special cytological features. Compared with Perrottetia, Dipentodon has a different basic chromosome number, a higher karyotype asymmetry, and different karyomorphology of its interphase nuclei, mitotic prophase, and metaphase. Thus, on the basis of these results, we have reservations regarding the suggestion of placing Dipentodon and Perrottetia together in the family Dipentodontaceae.  相似文献   

19.
By detecting the indicators of seeds such as the morphology and physiological characteristics within three consecutive years, the effects of different storage temperatures and time, and different media on seed germination of Tetracentron sinense were discussed, and also the endangered mechanism associated with biological characteristics of seeds was analyzed. The seeds of T.sinense were very small. No significant difference existed associated with seed morphology, 1000 seed weight, water content and plumpness, except for water absorption rate among seeds from different year, and the water absorption rate of seeds from 2007 was the fastest. The TTC results showed that the percentage of seed vigor was close to zero, but the vigor index of seeds among different year was respectively 0, 041 and 027, which indicated that TTC was not suitable for the estimation of Tsinense seed vigor. After stored at lower temperature, the germination rate of these seeds was respectively 125%、965%、708%, and the germination force was 1%、598%、418%. With the increase of storage time, seeds vigor of three years would decrease gradually, but the loss rate of seed vigor from 2007 was the slowest compared with other years. After stored at room temperature, the seed vigor would decrease even faster with the increase of storage time, compared with that stored at lower temperature. Different media had a certain effect on seed germination and seedling growth. The results showed that seed vigor from an abundant year was better than that of off year, and would decrease even slower than that of off year with the increase of storage time. The storage at lower temperature was favorable to the maintenance of seed vigor. The reasons resulted in severe danger related to Tsinense seeds are as follows: (1) Small seeds contributed to the spread and dispersal of species, was not beneficial to the survival of seed and seedling. (2) Perennial low temperature was not suitable for seed germination and the formation of a seedling pattern; (3) Perennial moist environment was not suitable for seed living through cold period safely.  相似文献   

20.
《微生物学通报》2007,34(3):597-597
本书是关于动物分类单元名称的命名和正确使用的国际性法规,是获得国际动物命名法委员会认可的《国际动物命名法规》英文版第四版的中文译本(简体字版),包括对第四版中主要变化的说明、导言,共18章90条条款和词汇,以及具有荐则地位的附录和国际动物命名法委员会章程。  相似文献   

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