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221.
Uptake of amino acids by the cyanobacterium Anabaena ATCC 27893 总被引:1,自引:0,他引:1
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Abstract. The genus Homoeogenus Waterhouse is revised. H.punctatum Waterhouse is redescribed, and two new species, H.chinensis sp.n. (Szechuan) and H.laurae sp.n. (Taiwan), are described. The morphology of the immature stages and the ecology of H.laurae are described. A key to the Oriental genera of Eubriinae is included. 相似文献
223.
本文通过主动脉和左肾动脉缩窄复制心功能不全大鼠模型,并采用放射配基结合实验和半定量逆转录-聚合酶链反应(RT-PCR),从蛋白质和基因转录水平上观察在心功能不全时大鼠心脏α1-肾上腺素受体三种亚型的改变。Scatchard分析结果显示,在心功能不全组与对照组,大鼠心脏组织125I-BE与α1-肾上腺素受体结合的亲和性(229±32与195±15pmol/L)和数量(102±12与96±17fmol/mg)均无显著差异。但WB4101对125I-BE的竞争性抑制实验显示在心功能不全组高亲和性位点所占百分比较对照组显著增高(51±7%与22±5%)。RT-PCR的结果显示,在心功能不全大鼠心脏α1A-AR的mRNA水平高于对照组,但α1B-AR的mRNA水平低于对照组,而α1D-AR的mRNA水平在两组之间没有显著差异。综合上述结果可知,在心功能不全大鼠,心脏α1A-AR增加,α1B-AR下降,而α1D-AR则没有显著改变。 相似文献
224.
NORIHIRO KURAISHI MASAFUMI MATSUI AMIR HAMIDY DAICUS M. BELABUT NORHAYATI AHMAD SOMSAK PANHA AHMAD SUDIN HOI S. YONG JIAN‐PING JIANG HIDETOSHI OTA HO T. THONG KANTO NISHIKAWA 《Zoologica scripta》2013,42(1):54-70
Kuraishi, N., Matsui, M., Hamidy, A., Belabut, D. M., Ahmad, N., Panha, S., Sudin, A., Yong, H. S., Jiang, J.‐P., Ota, H., Thong, H. T. & Nishikawa, K. (2012). Phylogenetic and taxonomic relationships of the Polypedates leucomystax complex (Amphibia). —Zoologica Scripta, 42, 54–70. We investigated the phylogenetic and taxonomic relationships and estimated the history of species diversification and biogeography in the Asian rhacophorid genus Polypedates, focusing on the Polypedates leucomystax complex, whose members are notoriously difficult to classify. We first estimated phylogenetic relationships within the complex using 2005‐bp sequences of the mitochondrial 12S rRNA, tRNAval and 16S rRNA genes with maximum parsimony, maximum likelihood (ML) and Bayesian methods of inference. Polypedates exhibits well‐supported monophyly, with distinct clades for P. otilophus, P. colletti, P. maculatus and the P. leucomystax complex, consisting of P. macrotis, and the Malay (Polypedates sp. from Malay Peninsula), North China (P. braueri), South China (Polypedates cf. mutus 1), Indochina (P. megacephalus), Sunda (P. leucomystax) and Laos (Polypedates cf. mutus 2) clades. In a subsequent phylogenetic analysis of 4696‐bp sequences of the nuclear brain‐derived neurotrophic factor (BDNF), sodium/calcium exchanger 1 (NCX), POMC, Rag‐1, Rhod and Tyr genes using Bayesian methods of inference, all of these clades were recovered. Some clades of the P. leucomystax complex occur sympatrically and show high genetic diversity or morphological and acoustic differences. Similar tendencies were observed between some allopatric clades. Therefore, we consider each of these groups to be distinct specifically. We also estimated absolute divergence times within the genus using Bayesian methods. Divergence in Polypedates began with the divergence of a primarily South Asian Clade from the common ancestor of secondarily South‐East Asia P. maculatus and South‐East Asian members. The divergence between the latter occurred much later. The P. leucomystax complex diverged in the Pliocene, much later than other congeners, and seems to have been greatly affected by human‐related dispersal after the Pleistocene. 相似文献
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226.
The role of biofoam in shielding spittlebug nymphs (Insecta,Hemiptera, Cercopidae) against bright light
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XU CHEN V. BENNO MEYER‐ROCHOW ALBERTO FERERES MARINA MORENTE AI‐PING LIANG 《Ecological Entomology》2018,43(3):273-281
1. Biofoam in spittlebugs has traditionally been seen as a defence against predation and a microclimate that reduces the risks of overheating and drying out. This study addresses the possible role of the foam as a light attenuator. 2. Nymphs exhibit higher mortalities when reared under brighter light (1800–2000 lux) than under less bright light (600–800 lux). At all developmental stages, photoavoidance is strongest when the nymphs are depleted of foam covers. First‐ and second‐instar nymphs appear to be the most vulnerable to exposures by bright light. 3. Smaller bubbles are more effective as light attenuators than are larger ones. As younger instars possess smaller canals from which bubbles are released and, furthermore, exhibit higher concentrations of proteins in bubble liquid, they can produce smaller‐sized bubbles and their foams are more effective at reducing light than are those of older nymphs. 4. The findings of this study show that most of the visible and UV radiation is reflected by the foam: transmittance of visible light was 15% at 600 nm and 12% at 350 nm. 5. These results demonstrate that spittlebug foam also possesses properties that render it an effective barrier against potentially damaging solar radiation. 相似文献
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Abstract The new planthopper taxon, Garumnella bella gen.n. , sp.n. , from Xizang, China, is described and illustrated, including external morphology of adult and eggs and structures of the male and female genitalia. The new genus is compared with Garumna Melichar and Paragarumna Muir, resulting in Paragarumna ( syn.n. ) being placed as a junior synonym of Garumna, with two new combinations, i.e. Garumna pseudolepida (Muir) comb.n. and Garumna melichari Baker comb.rev. New locality records for Garumna species are given. The morphology of the genitalia and egg of a copulating pair of the new genus is investigated. The female has a ventrally sclerotized posterior vagina forming a torsion groove, an unusual long membranous anterior vagina and an enlarged common oviduct. During copulation both the aedeagus and the torsion groove appear tightly interlocked, which may help to maintain the copulatory position. The aedeagus is observed in the bursa copulatrix. 相似文献
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