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1.
吴玉环  高谦 《植物研究》2005,25(1):19-21
细齿缺萼苔(G. crenulatum Gott. ex Carr.)的中国记录为错误鉴定,标本实为中华缺萼苔(G. sinense K. Muell.),应被移出中国苔藓植物区系。研究发现了多号西藏产中华缺萼苔标本,将中华缺萼苔其在中国的分布范围从云南的模式产地扩展到了西藏。对中华缺萼苔进行了形态特征描述和分布分析,并提供了特征示意图。  相似文献   

2.
对产自中国云南缺萼苔科(Gymnomitriaceae)粗疣类钱袋苔(Apomarsupella verrucosa (Nichols.) Vana)和产自尼泊尔(Gymnomitrion papillosum Kitag. &; S. Hatt.)的模式标本进行了对比研究, 发现Gymnomitrion papillosum和粗疣类钱袋苔特征相一致, 将其处理为粗疣类钱袋苔的异名。  相似文献   

3.
程前  师雪芹 《广西植物》2018,38(9):1229-1233
该文报道了5种安徽苔类植物新记录,即刺茎拟大萼苔(Cephaloziella spinicaulis Douin)、钝角顶苞苔[Acrobolbus ciliatus(Mitt.)Schiffn.]、上海羽苔(Plagiochila shangaica Steph.)、日本小叶苔(Fossombronia japonica Schiffn.)和单月苔(Monosolenium tenerum Griff.),分别隶属于拟大萼苔科、顶苞苔科、羽苔科、小叶苔科和单月苔科。其中,顶苞苔科、小叶苔科和单月苔科为安徽省新记录科。同时,对这几个种的主要识别特征和地理分布进行了讨论。  相似文献   

4.
报道陕西秦岭的2个苔类新记录种:红色拟大萼苔[Cephaloziella rubella(Nees) Warnst.]和被刺拟大萼苔(Cephaloziella spinicaulis Douin.)。根据标本对2种植物的形态进行了详细的描述,同时对其地理分布进行了简要说明。  相似文献   

5.
描述了光萼苔属的一个新种和一个新变种:卷瓣光萼苔Porella recurve-loba和多齿光萼苔全缘变种P.campylophylla(Lehm.Lindenb.)Trev.var.integra,它们分别采自中国甘肃和云南。提供了上述新分类群的描述和线条图,并且讨论了与它们形态相似种类之间的区别特征。  相似文献   

6.
报道云南中越边境西隆山苦苣苔科一新种,即金平漏斗苣苔(Raphiocarpus jinpingensis W.H.Chen Y.M.Shui)。该新种在花冠形态和淡黄色花色特征上近似合萼漏斗苣苔(R.petelotii(Pellegr.)Burtt),但是植株密被柔毛、萼筒与萼裂片近等长而与后者不同。对该新种的种子和花粉的微形态进行了观察和描述。  相似文献   

7.
吴玉环  高谦 《植物研究》2008,28(5):520-522
报道产于云南的中国苔类植物地萼苔科大陆新记录种: 锡金裂萼苔(Chiloscyphus sikkimensis(Steph.) J.J. Engel &; R.M. Schust.)。本种的主要区别特征有:茎叶倾斜或近横向着生,近轴端凸起,近似圆形,叶边全缘,卵形,先端圆钝或微凹;腹叶心形或肾形,先端圆钝或微凹,一侧或两侧基部与茎叶腹边联生。报道于台湾的Heteroscyphus acutangulus(Schiffn.) Schiffn. 实为Chiloscyphus sikkimensis,应被移出中国苔藓植物区系。  相似文献   

8.
报道产于西藏和云南的中国苔类植物缺萼苔科类钱袋苔属1 个新记录种: 疣茎类钱袋苔Ap omarsup ella
crystallocaulon ( Grolle) Vana。该种主要特征为茎皮部细胞角质层具透明疣, 有别于本科其他种类。  相似文献   

9.
报道产于西藏和云南的中国苔类植物缺萼苔科类钱袋苔属1个新记录种:疣茎类钱袋苔Apomarsupella crystallocaulon(Grolle)Vana。该种主要特征为茎皮部细胞角质层具透明疣,有别于本科其他种类。  相似文献   

10.
作者在研究新疆紫萼藓科植物时,发现了紫萼藓属(Grimmia Hedw.)植物4个新记录种,包括Grimmia capillata,紫萼藓(G. plagiopodia),贺兰山紫萼藓(G. crassiuscula)和卷叶紫萼藓(G. incurva),其中G. capillata为中国新分布。该研究对新记录种的形态特征、地理分布进行了详细描述,将其与属内相似种进行了比较分析。  相似文献   

11.
中国东北早白垩世一种新的昼蜓化石 (蜻蜓目: 昼蜓科)   总被引:2,自引:0,他引:2  
任东  刘金远  程晓冬 《昆虫学报》2003,46(5):622-628
本文记述昼蜓科化石一新属新种-孟氏丽昼蜓Abrohemeroscopus mengi gen.et sp.nov.。化石采自辽宁省义县早白垩世九佛堂组地层中。新属与巴依萨昼蜓Hemeroscopus Pritykina,1977在形态上比较相似,但在演化程度上更为原始,主要体现在下面几个方面:(1) 后翅臀套较小,仅有6~7个翅室; (2) 径增脉(Rspl)缺; (3) 后翅CuAa脉弯曲,带有5个明显的后分支; (4)前翅MP脉不显短,终止于翅后缘近翅结处; (5) 翅痣下有一个明显的支脉; (6) 后翅CuAa 和MP域基部较窄,在三角室下方仅有1排翅室。这是昼蜓科化石在中国的最老记录。  相似文献   

12.
The widespread opinion that N(2)O(3) as a product of NO oxidation is the only nitros(yl)ating agent under aerobic conditions is based on experiments in homogeneous buffered water solutions. In vivo NO is oxidized in heterogeneous media and this opinion is not correct. The equilibrium in the system being dependent on temperature and DeltaG((sol)) for NO, NO(2), isomers of both N(2)O(3), and N(2)O(4). For polar solvents including water, DeltaG((sol)) for N(2)O(3) is high enough, and a stationary concentration of N(2)O(3) in the mixture with other oxides is sufficient to guarantee the hydrolysis of N(2)O(3) to nitrite. In heterogeneous media, the mixture contains solvates NO(2(sol)), N(2)O(3(sol)), and N(2)O(4(sol)) at stationary nonequilibrium concentrations. As far as DeltaG((sol)) is decreased in heterogeneous mixtures with low polar solvents and/or at increased temperatures, the equilibrium in such a system shifts to NO(2). Although NO(2) is a reactive free radical, it almost does not react with water. In contrast, the reaction with most functional protein groups efficiently proceeds by a radical type with the formation of nitrite and new radicals (X) further stabilized in various forms. Therefore, the ratio of the nitrosylated and nitrated products yields depends on actual concentrations of all NO(x).  相似文献   

13.
The context is the general stochastic differential equation (SDE) model dN/dt=N(g(N)+sigmaepsilon(t)) for population growth in a randomly fluctuating environment. Here, N=N(t) is the population size at time t, g(N) is the 'average' per capita growth rate (we work with a general almost arbitrary function g), and sigmaepsilon(t) is the effect of environmental fluctuations (sigma>0, epsilon(t) standard white noise). There are two main stochastic calculus used to interpret the SDE, It? calculus and Stratonovich calculus. They yield different solutions and even qualitatively different predictions (on extinction, for example). So, there is a controversy on which calculus one should use. We will resolve the controversy and show that the real issue is merely semantic. It is due to the informal interpretation of g(x) as being an (unspecified) 'average' per capita growth rate (when population size is x). The implicit assumption usually made in the literature is that the 'average' growth rate is the same for both calculi, when indeed this rate should be defined in terms of the observed process. We prove that, when using It? calculus, g(N) is indeed the arithmetic average growth rate R(a)(x) and, when using Stratonovich calculus, g(N) is indeed the geometric average growth rate R(g)(x). Writing the solutions of the SDE in terms of a well-defined average, R(a)(x) or R(g)(x), instead of an undefined 'average' g(x), we prove that the two calculi yield exactly the same solution. The apparent difference was due to the semantic confusion of taking the informal term 'average growth rate' as meaning the same average.  相似文献   

14.
Hyolith assemblages of early to mid Ordovician age in Sweden include the hyolithids Hyolithus bisulcatus Holm, H. concinnus Holm and H. innotatus Holm, which are confirmed as representatives of Hyolithes Eichwald. Dorsolinevitus Syssoiev is known from D. dispar (Holm), D. textilis (Holm) and D. vomer (Holm), and Carinolithes Syssoiev is represented by C. hospes (Holm) and C. triumvir (Holm). Sulcavitus caelatus (Holm), the type species that forms the basis for a family and even an order according to some, is redescribed; the order is suppressed. Hyolithus cymbium Holm is transferred to Stelterella gen. nov., and Theca crispata (Boll) is now the type species of Crispatella gen. nov. The unusual orthothecid Quadrotheca quadrangularis (Holm) is redescribed; the concept of Trapezotheca aemula (Holm) is emended, and Semielliptotheca dens (Holm) is transferred to Trapezotheca . Semielliptotheca Syssoiev is poorly known from only one species, S. rosmara (Holm), and that genus is now considered to be unrecognizable. Hyolithus exaratus Hadding is identified as closely related to the gastropod Lytospira norvegica Koken, and specimens of Hyolithus sp. nos 11, 12 and 13 Holm and Hyolithus sp. indet. Wiman, remain to be located.  相似文献   

15.
Apoptosis is characterized by the proteolytic cleavage of hundreds of proteins. One of them, the type 1 inositol-1,4,5-trisphosphate receptor (IP(3) R-1), a multimeric receptor located on the endoplasmic reticulum (ER) membrane that is critical to calcium homeostasis, was reported to be cleaved during staurosporine (STS) induced-apoptosis in Jurkat cells. Because the reported cleavage site separates the IP(3) binding site from the channel moiety, its cleavage would shut down a critical signaling pathway that is common to several cellular processes. Here we show that IP(3) R-1 is not cleaved in 293 cells treated with STS, TNFα, Trail, or ultra-violet (UV) irradiation. Further, it is not cleaved in Hela or Jurkat cells induced to undergo apoptosis with Trail, TNFα, or UV. In accordance with previous reports, we demonstrate that it is cleaved in a Jurkat cell line treated with STS. However its cleavage occurs only after poly(ADP-ribose) polymerase (PARP), which cleavage is a hallmark of apoptosis, and p23, a poor caspase-7 substrate, are completely cleaved, suggesting that IP(3) R-1 is a relatively late substrate of caspases. Nevertheless, the receptor is fully accessible to proteolysis in cellulo by ectopically overexpressed caspase-7 or by the tobacco etch virus (TEV) protease. Finally, using recombinant caspase-3 and microsomal fractions enriched in IP(3) R-1, we show that the receptor is a poor caspase-3 substrate. Consequently, we conclude that IP(3) R-1 is not a key death substrate.  相似文献   

16.
磁场处理蕃茄种子对幼苗CAT、POD酶活性影响   总被引:6,自引:0,他引:6  
贾媛  马跃  王占斌 《生物技术》2000,10(2):14-17
磁场处理蕃茄种子,观察种子的发芽率幼苗的过氧化氢酶(CAT)和过氧化物酶(POD)活性的变化,结果,磁场强度在1000~2000GS范围内,种子发芽率最高,幼苗的过氧化氢酶的过氧化物酶的活性也最高,磁场强度高于3000GS以上时,种子发芽率和幼苗酶活性随之降低。  相似文献   

17.
章伟  祝宏  吕沁风  王炜  韩浙东  朱发明  严力行 《遗传》2007,29(2):185-189
为了探讨浙江汉族人群13种细胞因子基因多态性的分布情况, 采用PCR-SSP对100名汉族人群的IL-1α(T/C-889)、IL-1β(C/T-511, T/C+3962)、IL-1R(C/T Pst-I 1970)、IL-1RA(T/C Mspa1-I 1100)、IL-2 (T/G -330, G/T +166)、IL-4 (T/G -1098, T/C -590, T/C -33)、IL-4Rα(G/A +1902)、IL-6 (G/C-174, G/A nt565)、IL-10 (G/A -1082, C/T -819, C/A-592)、IL-12(C/A -1188)、gIFN (A/T UTR 5644)、TGFβ(C/T codon 10, G/C codon 25)、TNFα(G/A -308, G/A -238)等细胞因子基因多态性进行分型。结果显示, (1)在检测的13种细胞因子中, TGF(G codon 25)等位基因频率为1.00, 未检测到TGF(C codon 25)等位基因; (2)细胞因子等位基因频率大于0.95的有IL-1α(C-889)、IL-1β(C +3962)、IL-4 (T –1098)、IL-6 (G-174)、IL-6(G nt565)、IL-10(A –1082)和TNFa (G -238); 频率低于0.05的有IL-1α(T -889)、IL-1β(T +3962)、IL-4(G –1098)、IL-6 (A-174)、IL-6 (A nt565)、IL-10 (G –1082) 和TNFa (A -238); (3) IL-10高表达单倍型GCC频率为0.05, 低表达单倍型ATA频率为0.735; TGF β高表达单倍型TG频率为0.49, 低表达单倍型CC频率为0; TNF a高表达单倍型AG和AA频率为0.055, 低表达单倍型GG和GA频率为0.945。结果表明, 浙江汉族人群细胞因子基因多态性较为丰富, 具有地区性遗传特征。  相似文献   

18.
We extend to harvesting stochastic differential equation (SDE) models in a random environment our previous work on models without harvesting concerning the resolution of the It?-Stratonovich controversy. The resolution is obtained for the very general class of models dN/dt=N (r(N)-h(N)+sigmaepsilon(t)), where N=N(t) is the population size at time t, r(N) is the (density-dependent) "mean" per capita growth rate, h(N) is the (density-dependent) harvesting effort, epsilon(t) is a standard white noise (representing environmental random fluctuations), and sigma is a noise intensity parameter. It? and Stratonovich calculus in the resolution of SDEs apparently give different qualitative and quantitative results, leading to controversy on which calculus is more appropriate and creating an obstacle on the use of this modeling approach. We show that the apparent difference between the two calculi is due to a semantic confusion based on the fallacious assumption that we are working with the same type of mean rates. After clearing the confusion, the two calculi yield exactly the same results and we obtain important common conditions for extinction and for existence of a stationary density. The resolution of the controversy is intertwined with and sheds light on the estimation issues.  相似文献   

19.
阿拉善黄鼠的生命表及繁殖   总被引:2,自引:1,他引:1  
陈敬先 《兽类学报》1991,11(2):138-142
将采自野生种群的阿拉善黄鼠(Spermophilus dauricus alaschanicus Buechner)( 下称黄鼠)样本划分为8个年龄间隔,然后编制生命表。结果表明,黄鼠的平均死亡率(qx)为0.7512(♂)和0.6222(♀),平均寿命为1.3311年(♂)和1.1073年(♀)。0-l岁龄黄鼠的期望寿命(ex)为0.8311年(♂)和1.1073年(♀)。世代净增殖率(Ro)每代为l.7327。种群内禀增长率(瞬时)(rm)为0.1433,世代平均时间(T)为3.8346年,周限增长率(r)为1.1541/年。  相似文献   

20.
During activation of the phagocyte (Nox2-based) NADPH oxidase, the cytoplasmic Phox complex (p47(phox)-p67(phox)-p40(phox)) translocates and associates with the membrane-spanning flavocytochrome b(558). It is unclear where (in cytoplasm or on membranes), when (before or after assembly), and how p40(phox) acquires its PI(3)P-binding capabilities. We demonstrated that in addition to conformational changes induced by H(2)O(2) in the cytoplasm, p40(phox) acquires PI(3)P-binding through direct or indirect membrane targeting. We also found that p40(phox) is essential when p47(phox) is partially phosphorylated during FcγR-mediated oxidase activation; however, p40(phox) is less critical when p47(phox) is adequately phosphorylated, using phosphorylation-mimicking mutants in HEK293(Nox2/FcγRIIa) and RAW264.7(p40/p47KD) cells. Moreover, PI binding to p47(phox) is less important when the autoinhibitory PX-PB1 domain interaction in p40(phox) is disrupted or when p40(phox) is targeted to membranes. Furthermore, we suggest that high affinity PI(3)P binding of the p40(phox) PX domain is critical during its accumulation on phagosomes, even when masked by the PB1 domain in the resting state. Thus, in addition to mechanisms for directly acquiring PI(3)P binding in the cytoplasm by H(2)O(2), p40(phox) can acquire PI(3)P binding on targeted membranes in a p47(phox)-dependent manner and functions both as a "carrier" of the cytoplasmic Phox complex to phagosomes and an "adaptor" of oxidase assembly on phagosomes in cooperation with p47(phox), using positive feedback mechanisms.  相似文献   

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