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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.
辣椒素引起脊髓P物质释放及其对血压的影响 总被引:5,自引:0,他引:5
为进一步研究脊髓 P 物质(SP)在调节心血管活动中的作用,在大鼠脊髓蛛网膜下腔注射(ith)辣淑素(cap),以刺激脊髓 SP 能神经末梢释放 SP,结果引起血浆去甲肾上腺素(NA)和肾上腺素(AD)含量增高,及具有剂量依赖性的动脉血压上升,心率升高。ith 具有高度特异性的 SP 受体拮抗剂或 SP 抗血清均可阻断 cap 引起的升压效应,免疫组化测定也观察到注入的cap 剂量越大,脊髓胸段 SP 样免疫阳性反应物的致密度越低,这些观察结果支持 cap 可以引起脊髓内 SP 的释放的说法。在第一颈段(C_1)横断脊髓后 ith cap 所引起的升压效应与完整动物 ith cap 的升压效应无显著差异。以上结果提示脊髓 SP 能神经末梢释放的 SP 可以通过交感肾上腺髓质系统引起心血管兴奋效应,SP 可能是引起交感节前神经元兴奋的神经递质。 相似文献
3.
本文报道了岩羊小肠的祁连毛圆线虫,新种Trichostrongylus qilianensis sp. nov., 其形态与已发表的39种毛圆线虫均有明显区别。 相似文献
4.
反复电针对慢性痛的累加治疗作用及其机制研究 总被引:22,自引:0,他引:22
本研究从基础和临床两方面观察了反复电针对慢性痛的累加治疗作用,并结合疼痛患者及慢性痛动物模型中几种神经肽的放射免疫测定及相应受体拮抗剂的药理学研究结果,探讨了产生累加效应的可能机制。结果表明,在临床脊髓损伤性痉挛患者,100Hz穴位体表电刺激有效地缓解痉挛并有累加效应;在临床慢性痛患者,2/15Hz变频TENS刺激有效地治疗疼痛并具有累加效应。在关节炎模型大鼠,电针刺激能产生明显的镇痛并具有累加效 相似文献
5.
将菠菜叶片匀浆后.用差速离心和梯度率心分离叶绿体、过氧物酶体、微粒体等细胞器和100000×g上清法部分。用酶活测定法测定各部分甜菜碱醛脱氢酶(BADH)的活性;用免疫扩散法鉴定各组分的BADH。除叶绿体外,过氧物酶体、微粒体.以及100000×g上清液中也存在BADH。 相似文献
6.
At elevated atmospheric CO2 concentrations ([CO2]a), photosynthetic capacity (Amax) and root fraction (ηR, the ratio of root to plant dry mass) increased in some studies and decreased in others. Here, we have explored possible causes of this, focusing on the relative magnitudes of the effects of elevated [CO2]a on specific leaf (nm) and plant (np) nitrogen concentrations, leaf mass per unit area (h), and plant nitrogen productivity (α). In our survey of 39 studies with 35 species, we found that elevated [CO2]a led to decreased nm and np in all the studies and to increased h and α in most of the studies. The magnitudes of these changes varied with species and with experimental conditions. Based on a model that integrated [CO2]a-induced changes in leaf nitrogen into a biochemically based model of leaf photosynthesis, we predicted that, to a first approximation, photosynthesis will be upregulated (Amax will increase) when growth at increased [CO2]a leads to increases in h that are larger than decreases in nm. Photosynthesis will be downregulated (Amax will decrease) when increases in h are smaller than decreases in nm. The model suggests that photosynthetic capacity increases at elevated [CO2]a only when additional leaf mesophyll more than compensates the effects of nitrogen dilution. We considered two kinds of regulatory paradigms that could lead to varying responses of ηR to elevated [CO2]a, and compared the predictions of each with the data. A simple static model based on the functional balance concept predicts that ηR should increase when neither np nor h is very responsive to elevated [CO2]a. The quantitative and qualitative agreement of the predictions with data from the literature, however, is poor. A model that predicts ηR from the relative sensitivities of photosynthesis and relative growth rate to elevated [CO2]a corresponds much more closely to the observations. In general, root fraction increases if the response of photosynthesis to [CO2]a is greater than that of relative growth rate. 相似文献
7.
8.
乙烯诱导下草莓果实采后RNA代谢与蛋白质合成活性的变化 总被引:3,自引:0,他引:3
草莓草果实在乳白时期采收(开花后约40d),分别用10μl/L,50μl/L和100μl/L的外源乙烯进行处理。处理后的果实大分子RNA和poly(A)+RNA水平以及poly(A)+RNA与总RNA的比例均有增高。果实体内RNA酶活性和体外蛋白质的合成水平也升高。乙烯很可能是促进草莓果实成熟衰老的因素之一。 相似文献
9.
KOWICHI JIMBOW DONG LUO HUA CHEN HIROYUKI HARA MU HYOUNG LEE 《Pigment cell & melanoma research》1994,7(5):311-319
In order to better understand the cascade of melanogenic events in melanocytes, this report has introduced our two recent approaches for the expression of melanogenesis/or melanosome-associated genes and encoded proteins in melanocytes (melanoma cells) after repeated exposure to UV -B and after cotransfection of two human genes, i.e., tyrosinase and tyrosinase-related protein-1 (TRP-1). Repeated exposure of UV B (2.5–5.0 mJ/cm2) caused not only upregulation of tyrosinase and TRP-1 genes but also coordinated increase in the gene and protein synthesis expression of Lamp-1 (lysosome-associated membrane protein-1). When COS-7 kidney cells and amelanotic melanoma (C32 and SKMEL-24) and melanotic melanoma (G361 and SK-MEL-23) cells were exposed to cotransfection of human tyrosinase and TRP-1 cDNAs, there was also an increased expression of Lamp-1 mRNA and protein along with tyrosinase activation and new melanin synthesis. Importantly, single transfectants of human tyrosinase cDNA revealed marked cellular degeneration, whereas this degeneration was not seen in single transfectants of TRP-1 cDNA or cotransfectants of human tyrosinase and TRP-1 cDNAs, indicating that TRP-1 prevented, along with Lamp-1, programmed death of melanocytes after transfection of tyrosinase gene. The coordinated expression of TRP-1 and Lamp-1 was further confirmed by antisense oligodeoxynucleotide hybridization experiment against Lamp-1 gene, showing the decreased expression of TRP-1 as identified by three different types of anti-TRP-1 monoclonal antibodies. We propose therefore that human tyrosinase and TRP-l, when activated or expressed together, will coordinate to upregulate the mRNA expression and protein synthesis of Lamp-1. The Lamp-1 molecules will, in turn, cover the inner surface of melanosomal membrane, together with TRP-1 molecules, thus protecting the melanosomal membrane from toxic melanin intermediates generated during melanogenesis in the presence of active tyrosinase. In contrast, the expression of other lysosome-related proteins, e.g., β-galactosidase and CD63 is not stimulated in new melanogenesis. 相似文献
10.
温度对草地螟成虫产卵和寿命的影响 总被引:9,自引:1,他引:8
在16℃、19℃、22℃、25℃.28℃,31℃和34℃的范围内, 草地螟(Loxostege sticticalis L.)成虫的产卵前期与温度的关系呈逻辑靳谛曲线,产卵雌蛾数、产卵历期和产卵量均以22℃为最高。初步确定19-25℃为草地螟蛾产卵的适温范围,22℃为最适产卵温度,16℃和34℃分别为产卵温度的下限和上限。成虫寿命与温度的关系为负相关(r=-0.91,P<0.01)。表明在试验温度范围内,温度越高,成虫寿命越短。但温度对雌雄成虫寿命的影响不一致,在28℃以下的温度内,雄蛾寿命比雌蛾长;在31-34℃的范围内,雄蛾寿命比雌蛾短。根据以上研究结果,对我国草地螟发生为害区的种群动态规律进行了讨论。 相似文献