733 resultados para Gall wasps.
Resumo:
The paper deals with the collection of gall bladders, isolation of bile and identification of the constituents of the bile salts from different fishes. The yield of bile contents from fresh water fishes rohu, mrigal and catla was compared with that from marine fishes seer, tuna, shark and sardine. Considerable variation in yield was showed between marine and fresh water fish as well as between the species in both groups. It ranged from 0.04 to 0.06% of the body weight of fish in calla, mrigal and rohu. The bile constituents from rohu and mrigal were analysed by thin layer chromatography. The result showed that bile of rohu and mrigal contains mainly taurine derivative of lithocholic acid.
Resumo:
云南高原位于北纬21°9′~29°15′和东经97°39′~106°12′之间,总面积394000 km2 ,地质和气候、植被非常复杂。大 陆漂移和冰期的进退是影响昆虫起源和演替的一个重要原因。昆虫的祖先是起源于一个统一大陆,在这个大陆上共 同起源,共同进化,随着原始大陆的分离和漂移,把这些类群运载到各地,形成现今昆虫分布格局。昆虫的扩散是以中 心分布方式成环状向周围扩散的。云南胡蜂的祖先是来自冈瓦那古陆。有两支昆虫进入云南,其中一支来自喜马拉 雅山,另一支来自缅甸。冰期是导致南北生物互相混合和渗入的重要因素。胡蜂的特有类群是在冈瓦那古陆分裂之 后才发展起来的。其祖先最早是分布在原始古陆较狭窄的区域内。
Resumo:
Two new species of myxosporeans (Myxosporea: Myxidiidae), Myxidium tuanfengensis sp. n. and Zschokkella saurogobionis sp. n., Parasitic in freshwater fishes collected from the Yangtze River of China are described in this paper. M. tuanfengensis was found in the liver parenchyma and intestine lumen of Leptobotia taeniops Sauvage, 1878, while Z. saurogobionis was found in the gall bladder of Saurogobio dumerili Bleeker, 1871. The diagnostic characters of M. tuanfengensis are: round or elliptical polysporous plasmodia averaging 118 mum in size; spore oval in frontal view with smooth surface and nearly spindle-shape in sutural view with slightly sinuous sutural ridge, averaging 19.5 x 9.75 x 8.9 mum in size; two large spherical polar capsules 6.8 mum in diameter, with polar filament wound in 4 to 5 coils. The diagnostic characters of Z. saurogobionis are: spore elliptical in both frontal and sutural view measuring 18.3 x 9.8 x 10.8 mum in size; fine sutural ridge in S-form, spore shell marked with 10 to 12 distinct lines paralleled with the sutural line; two spherical polar capsules, 6.7 mum in diameter, with polar filament in 5 coils.
Resumo:
蛇毒和蜂毒是提供药理学活性分子的丰富来源,它们富含肽和蛋白,包括一 些酶类和毒素。 丝氨酸蛋白酶抑制剂广泛存在于动物、植物和微生物体内,参与许多重要的 生理过程,如血液凝集、纤维蛋白溶解、细胞凋亡、发育以及炎症反应和补体活 化等(van Gent D. et al., 2003)。通过凝胶过滤、离子交换和反向高压液相色谱, 我们从金环蛇毒液中纯化得到一种天然的丝氨酸蛋白酶抑制剂,命名为 bungaruskunin。并且从该蛇的毒腺cDNA 文库中克隆到了它的核苷酸序列。 bungaruskunin 预测的前体由83 个氨基酸组成,包括含有24 个氨基酸的信号肽 和含有59 个氨基酸的成熟肽。它与一种由红腹伊澳蛇(Pseudechis porphyriacus) 的cDNA 预测到的丝氨酸蛋白酶抑制剂blackelin 具有最大相似性,达64%。 Bungaruskunin 是一种Kunitz 型的蛋白酶抑制剂,具有一个保守的Kunitz 结构域, 能够抑制胰蛋白酶、胰凝乳蛋白酶和弹性蛋白酶。通过对金环蛇毒腺cDNA 文库 的筛选,我们还得到了另外两条β-bungarotoxin B 链,Bungaruskunin 的整体结 构与β-bungarotoxin B 链相似,特别是它们都具有高度保守的信号肽序列。这些 发现强烈地表明蛇毒Kunitz/BPTI 蛋白酶抑制剂与神经毒性的类似物可能起源于 共同的祖先。 肥大细胞脱粒肽是从膜翅目昆虫的毒液中鉴别出的一个小肽家族,是一种具 有潜在的药物治疗作用的诱导活性分子(Xueqing Xu et al., 2006)。来源于蜂类的 缓激肽样的类似物vespakinin 家族是一种具有调节和激素功能的活性成分,与哺 乳动物和两栖动物的缓激肽类似(Nakajima T., 1984)。本研究对三种胡蜂的 毒液进行了一系列的活性检测,发现黑尾胡蜂的蜂毒对白色念珠菌Candida albicans 和金黄色葡萄球菌 Staphylococcus aureus 有抑制作用。凹纹胡蜂和黑尾 胡蜂的蜂毒具有微弱的磷酯酶A2 活性。通过凝胶过滤和反向高压液相色谱,没 有得到相关的活性组分。通过对三种胡蜂毒腺cDNA 文库的筛选,我们得到了2 条来源于黑尾胡蜂的核苷酸序列,Blast 分析表明,其中一条编码类似肥大细胞 脱粒肽,但未克隆到全长,序列比对结果显示其与来源于大胡蜂(Vespa magnifica) 的Mastoparan-like peptide 12c precursor(GenBank accession A0SPI0)的核苷酸序 列相似性达98%(Xueqing Xu et al., 2006);另一条编码缓激肽类似物,命名为 Hw-bradykinin,序列比对结果显示其与来源于大胡蜂(Vespa magnifica)的 vespakinin-M precursor(GenBank accessionABG75944)的核苷酸相似率达96% (Zouhong Zhou et al., 2006)。
Resumo:
该项目以植物生理生态学(PlantPhysioecology)为研究方向,在藓类植物的光合特性及其与环境条件的关系,高温胁迫对藓类植物生理过程及生理生态学特性的影响,藓类植物光合作用与其水分含量和水势的关系等3个方面开展了大量深入的实验研究,取得了较好的实验结果.该项研究在苔藓植物生物学研究和冬寄主藓类植物人工培植方面既具有重要的理论意义,也具有重要的实际应用价值.
Resumo:
Plant galls constitute a branch of study and research which has been to me a subject of much interest for some time. At the start of this work, it was intended to include Plant galls in general, but after some months this was found to be too comprehensive a field and would in fact take a great many years to study fully. Even leaf galls alone, both of herbs and trees provide so large a field of investigation that ultimately I decided to confine my attention to those or our native trees and shrubs. Upon looking up the literature on this subject, it will be found that in nearly all cases, either the gall is described fully and mere mention made or the agent concerned in its production, or vice versa. This state of things is most unsatisfactory, as in studying galls, both the gall-maker and the gall formation must be examined in detail before it is safe to apply nomenclature. This work, therefore, sets out to give accurate and scientific descriptions of both galls and gall-makers. The difficulties encountered are manifold; firstly, our trees are all deciduous, hence, the collecting period is necessarily restricted to that time of the year between the appearance of the buds and the fall of the leaf. Secondly, the rearing of imagines is always difficult, especially in the case or the autumn gall; more will be said on this matter later. Lastly, due to war-time conditions much trouble was experienced in obtaining suitable literature and many invaluable books on this subject were unprocurable. The Plates at the back have all been copied from original material except in the case or the Phytoptid mites which have been sketched with the help of illustrations, the reason for this being the difficulty of making suitable mounts of these minute creatures, Where possible all stages or at least larva and imago have been sketched, together with the host plant and the type of gall-formation produced. Slides have also been made of most larvae and the imagines attached to cards and pinned on to pith or cork in the usual manner.
Resumo:
Phosphorylation of the beta(2) adrenoreceptor (beta(2)AR) by cAMP-activated protein kinase A (PKA) switches its predominant coupling from stimulatory guanine nucleotide regulatory protein (G(s)) to inhibitory guanine nucleotide regulatory protein (G(i)). beta-Arrestins recruit the cAMP-degrading PDE4 phosphodiesterases to the beta(2)AR, thus controlling PKA activity at the membrane. Here we investigate a role for PDE4 recruitment in regulating G protein switching by the beta(2)AR. In human embryonic kidney 293 cells overexpressing a recombinant beta(2)AR, stimulation with isoprenaline recruits beta-arrestins 1 and 2 as well as both PDE4D3 and PDE4D5 to the receptor and stimulates receptor phosphorylation by PKA. The PKA phosphorylation status of the beta(2)AR is enhanced markedly when cells are treated with the selective PDE4-inhibitor rolipram or when they are transfected with a catalytically inactive PDE4D mutant (PDE4D5-D556A) that competitively inhibits isoprenaline-stimulated recruitment of native PDE4 to the beta(2)AR. Rolipram and PDE4D5-D556A also enhance beta(2)AR-mediated activation of extracellular signal-regulated kinases ERK12. This is consistent with a switch in coupling of the receptor from G(s) to G(i), because the ERK12 activation is sensitive to both inhibitors of PKA (H89) and G(i) (pertussis toxin). In cardiac myocytes, the beta(2)AR also switches from G(s) to G(i) coupling. Treating primary cardiac myocytes with isoprenaline induces recruitment of PDE4D3 and PDE4D5 to membranes and activates ERK12. Rolipram robustly enhances this activation in a manner sensitive to both pertussis toxin and H89. Adenovirus-mediated expression of PDE4D5-D556A also potentiates ERK12 activation. Thus, receptor-stimulated beta-arrestin-mediated recruitment of PDE4 plays a central role in the regulation of G protein switching by the beta(2)AR in a physiological system, the cardiac myocyte.
Molecular analysis of photosynthetic picoeukaryote community structure along an Arabian Sea transect
Resumo:
DNA barcoding offers an efficient way to determine species identification and to measure biodiversity. For dinoflagellates, an ancient alveolate group of about 2000 described extant species, DNA barcoding studies have revealed large amounts of unrecognized species diversity, most of which is not represented in culture collections. To date, two mitochondrial gene markers, Cytochrome Oxidase I (COI) and Cytochrome b oxidase (COB), have been used to assess DNA barcoding in dinoflagellates, and both failed to amplify all taxa and suffered from low resolution. Nevertheless, both genes yielded many examples of morphospecies showing cryptic speciation and morphologically distinct named species being genetically similar, highlighting the need for a common marker. For example, a large number of cultured Symbiodinium strains have neither taxonomic identification, nor a common measure of diversity that can be used to compare this genus to other dinoflagellates.