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1.
QIAN‐WAN MENG YI‐BO LUO 《Botanical journal of the Linnean Society. Linnean Society of London》2008,158(4):689-695
A new species, Galearis huanglongensis Q.W.Meng & Y.B.Luo, is described and illustrated. It is similar to Galearis cyclochila (Franch. & Sav.) Soó and Galearis diantha (Schltr.) P.F.Hunt, but differs in having a short spur, two elliptical lateral stigma lobes and distinctly separated bursicles. This new species is known only from the type locality, the Huanglong Valley, Songpan County, western Sichuan, China, growing amongst mosses under alpine shrubs at an elevation of about 3000 m. Based on two years of observations of its population size, the species was categorized as critically endangered CR (B1a, B2a) according to the World Conservation Union (IUCN) Red List Categories and Criteria, Version 3.1. The micromorphology of pollinia and seeds was observed by scanning electron microscopy and compared with that of G. cyclochila and G. diantha. The results supported G. huanglongensis Q.W.Meng & Y.B.Luo as a new species. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 689–695. 相似文献
2.
After feeding GA20 to excised seedlings ofZea mays L. normals (N) and dwarf-1 mutants (d1), GA20-13-O-glucoside (9) was identified by HPLC and by GC-MS of its permethylated derivative. The glucosylation rate of GA20 was found to be higher in the dwarf-1 mutant (26%) than in the normal plant (3.6%). This article includes a GC-MS study in which diagnostic fragments from the spectra of permethylated synthetic GA glucosides have been selected that proved to be useful for the identification of permethylated GA glucosides. 相似文献
3.
培养的卒中型自发性高血压大鼠(SHR_(sp))及其对照 WKY 大鼠主动脉平滑肌细胞(VSMC)上存在心房钠尿肽(ANP)的特异性受体,它们与~(125)I-ANP 的最大结合量(B_(max))是:SHR_(sp)3.65±0.13和 WKY 1.89±0.09 pmol/mg pr(P<0.01);解离平衡常数(Kd)值分别是72.6±10.2和42.0±4.8×10~(-12)mol/L(P<0.01)。 两种细胞内介导舒血管作用的第二信使、环磷酸乌苷(cGMP)的基础浓度无显著差异,对相同剂量 ANP 刺激引起 cGMP 分别增加139(SHRsp)和271(WKY)倍。可见 SHRsp 的 VSMC ANP 受体数量虽比 WKY大鼠增多,但对相同剂量 ANP 引起的 cGMP 增加反应及 ANP 受体的亲和力均显著降低。高盐培养液孵育24h 后,细胞表面 ANP 受体的亲和力改变不明显,但受体数量下调,SHRsp 和 WKY 大鼠分别降至对照的34.8±8.2%和38.6±9.4%,细胞对 ANP 引起的 cGMP增加反应明显降低,且均以 SHR_(sp)较显著。提示后两种变化可能在高盐促进血压升高的机制中起作用。 相似文献
4.
本文报道了我国地下真菌3个新种和2个新记录,它们是:太原块菌Tuber taiyuanense Liu sp.nov.,苍岩山层腹菌Hymenogaster cangyan-shanensis Liu sp.nov.,山西须腹菌Rhizopogon shanxiensis Liu sp.nov.,棱孢层腹菌Hymenogaster fusisporus(Massee et Rodway)G.H.Cunningham以及小硬皮腹菌Sclerogaster minor Coker et Coudl。 相似文献
5.
6.
本文报道了黑蛋巢菌属Cyathus四个新种和二个新变种,它们分别是:内蒙黑蛋巢菌Cyathus neimonggolensis Liu et Y.M.Li,盘柄黑蛋巢菌C.discostipltatus Liu et Y.M.Li,太原黑蛋巢菌C.taiyuanensis Liu et Y.M.Li,毛被黑蛋巢菌C.hirtulus Liu et Y.M.Li,天山黑蛋巢毛被变种C.tianshanensis Liu et Cao var.tomentosus Liu, Cao et Y.M.Li,环状黑蛋巢武夷山变种 C. annulatus Brodie var. wuyishanensis Liu et Y.M.Li。全部模式标本均保存在山西大学真菌标本室。 相似文献
7.
Gibberellin A(3) Is Biosynthesized from Gibberellin A(20) via Gibberellin A(5) in Shoots of Zea mays L 总被引:11,自引:8,他引:3 下载免费PDF全文
Fujioka S Yamane H Spray CR Phinney BO Gaskin P Macmillan J Takahashi N 《Plant physiology》1990,94(1):127-131
[17-13C,3H]-Labeled gibberellin A20 (GA20), GA5, and GA1 were fed to homozygous normal (+/+), heterozygous dominant dwarf (D8/+), and homozygous dominant dwarf (D8/D8) seedlings of Zea mays L. (maize). 13C-Labeled GA29, GA8, GA5, GA1, and 3-epi-GA1, as well as unmetabolized [13C]GA20, were identified by gas chromatography-selected ion monitoring (GC-SIM) from feeds of [17-13C, 3H]GA20 to all three genotypes. 13C-Labeled GA8 and 3-epi-G1, as well as unmetabolized [13C]GA1, were identified by GC-SIM from feeds of [17-13C, 3H]GA1 to all three genotypes. From feeds of [17-13C, 3H]GA5, 13C-labeled GA3 and the GA3-isolactone, as well as unmetabolized [13C]GA5, were identified by GC-SIM from +/+ and D8/D8, and by full scan GC-MS from D8/+. No evidence was found for the metabolism of [17-13C, 3H]GA5 to [13C]GA1, either by full scan GC-mass spectrometry or by GC-SIM. The results demonstrate the presence in maize seedlings of three separate branches from GA20, as follows: (a) GA20 → GA1 → GA8; (b) GA20 → GA5 → GA3; and (c) GA20 → GA29. The in vivo biogenesis of GA3 from GA5, as well as the origin of GA5 from GA20, are conclusively established for the first time in a higher plant (maize shoots). 相似文献
8.
Biosynthetic Origin of Gibberellins A(3) and A(7) in Cell-Free Preparations from Seeds of Marah macrocarpus and Malus domestica 总被引:4,自引:4,他引:0 下载免费PDF全文
Cell-free preparations from seeds of Marah macrocarpus L. and Malus domestica L. catalyzed the conversion of gibberellin A9 (GA9) and 2,3-dehydroGA9 to GA7; GA9 was also metabolized to GA4 in a branch pathway. The preparation from Marah seeds also metabolized GA5 to GA3 in high yield; GA6 was a minor product and was not metabolized to GA3. Using substrates stereospecifically labeled with deuterium, it was shown that the metabolism of GA5 to GA3 and of 2,3-dehydroGA9 to GA7 occurs with the loss of the 1β-hydrogen. In cultures of Gibberella fujikuroi, mutant B1-41a, [1β,2β-2H2]GA4, was metabolized to [1,2-2H2]GA3 with the loss of the 1α- and 2α-hydrogens. These results provide further evidence that the biosynthetic origin of GA3 and GA7 in higher plants is different from that in the fungus Gibberella fujikuroi. 相似文献
9.
Mark A. Batzer Santosh S. Arcot Joshua W. Phinney Michelle Alegria-Hartman David H. Kass Stephen M. Milligan Colin Kimpton Peter Gill Manfred Hochmeister Panayiotis A. Ioannou Rene J. Herrera Donald A. Boudreau W. Douglas Scheer Bronya J. B. Keats Prescott L. Deininger Mark Stoneking 《Journal of molecular evolution》1996,42(1):22-29
The Alu family of intersperesed repeats is comprised of ovr 500,000 members which may be divided into discrete subfamilies based upon mutations held in common between members. Distinct subfamilies of Alu sequences have amplified within the human genome in recent evolutionary history. Several individual Alu family members have amplified so recently in human evolution that they are variable as to presence and absence at specific loci within different human populations. Here, we report on the distribution of six polymorphic Alu insetions in a survey of 563 individuals from 14 human population groups across several continents. Our results indicate that these polymorphic Alu insertions probably have an African origin and that there is a much smaller amount of genetic variation between European populations than that found between other populations groups.
Present address: Department of Pathology, Stanley S. Scott Cancer Center, Louisiana State University Medical Center, 1901 Perdido St., New Orleans, LA 70112
Correspondence to: M.A. Batzer 相似文献
10.
肾素-血管紧张素系统──应激激素反应系统 总被引:2,自引:0,他引:2
各种急性与慢性应激时,循环血中及脑、心血管、肾腺等组织中血管紧张素Ⅱ(AⅡ)显著增多;人剧烈运动后血浆AⅡ与皮质醇一样均剧烈增加,在慢性应激性高血压动物循环及组织中,AⅡ含量持续地增高。还发现高浓度AⅡ对肾上腺糖皮质激素的分泌有直接的刺激作用,而组织AⅡ增多又受肾上腺素能β受体的激发。根据近年来的系列工作,并结合文献,我们认为AⅡ是一种重要的应激激素;肾素-血管紧张素系统是一个应激激素反应系统;它与经典的应激激素反应系统,下丘脑-垂体-肾上腺皮质系统及交感-肾上腺髓质系统也存在着密切的关系。 相似文献