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61.
Qiu Baoli Susan A. Coats Ren Shunxiang Ali M. Idris Xu Caixia Judith K. Brown 《自然科学进展(英文版)》2007,17(6):645-654
Phylogenetic relationships for Bemisia tabaci were reconstructed by analysis of a ~780 bp fragment of the mitochondrial cytochrome oxidase I (mtCOI) gene with an emphasis on geographic range and distribution among eight eudicot plant families that are common hosts of B. tabaci worldwide to elucidate key phylogeographic linkages between populations extant in China (n=31) and India (n=34). Bootstrap values for the Maximum Parsimony tree were highly robust for all major nodes involving the major Asian clade, subgroups, and sister groups within, at 92%—100%. Between-clade distances for the Southeast Asia and three other major clades, e.g. from sub-Sahara Africa, North Africa-Mediterranean, and the Americas, were approximately >16% divergent. Two major Asian subgroups (I, II) were resolved, which represented populations indigenous to the region, comprising two (I a, I b) and five (II a—e) sister groups, respectively, which diverged by 11%. Two distinct populations from sunflower in Hyderabad grouped separately within the two Asian subgroups. All other populations grouped uniquely within Asian subgroup II or I. The "B" biotype was identified in 23 collections from China at 97.3%—99.5% nucleotide identity with "B" biotype reference sequences; it was not identified in collections from India. The majority of haplotypes were associated with 3—4 plant families, with one exception that for sister group IId (sesame, India), it might be monophagous. Thus, B. tabaci from the southeastern and near eastern regions of the Asian continent comprise of a large number of ancestral, richly divergent, mostly polyphagous populations. This region is therefore hypothesized to constitute an important Old World center of diversification for the B. tabaci complex, together with sub-Saharan Africa. 相似文献
62.
Scenario‐planning academicians and practitioners have been observing for more than three decades the importance of this method in dealing with environmental uncertainty. However, there has been no valid scale that may help organizational leaders to act in practice. Our review of prior studies identifies some problems related to conceptualization, reliability, and validity of this construct. We address these concerns by developing and validating a measure of scenario planning based on Churchill's paradigm (Journal of Marketing Research, 1979, 16, 64–73). Our data analysis follows from a sample of 133 managers operating in the healthcare field in France. To validate our scale, we used three approaches: first, an exploratory factor analysis; second, an examination of psychometric proprieties of all dimensions; and third, a confirmatory factor analysis. The results of this study indicate that scenario planning is a multidimensional construct composed of three dimensions: information acquisition, knowledge dissemination, and scenario development and strategic choices. 相似文献
63.
Ali Hashemi Gheinani Fiona C. Burkhard Katia Monastyrskaya 《Cellular and molecular life sciences : CMLS》2013,70(20):3773-3789
MicroRNAs (miRNAs), a novel class of molecules regulating gene expression, have been hailed as modulators of many biological processes and disease states. Recent studies demonstrated an important role of miRNAs in the processes of inflammation and cancer, however, there are little data implicating miRNAs in peripheral pain. Bladder pain syndrome/interstitial cystitis (BPS/IC) is a clinical syndrome of pelvic pain and urinary urgency/frequency in the absence of a specific cause. BPS is a chronic inflammatory condition that might share some of the pathogenetic mechanisms with its common co-morbidities inflammatory bowel disease (IBD), asthma and autoimmune diseases. Using miRNA profiling in BPS and the information about validated miRNA targets, we delineated the signaling pathways activated in this and other inflammatory pain disorders. This review projects the miRNA profiling and functional data originating from the research in bladder cancer and immune-mediated diseases on the BPS-specific miRNAs with the aim to gain new insight into the pathogenesis of this enigmatic disorder, and highlighting the common regulatory mechanisms of pain and inflammation. 相似文献
64.
Ahmed ZM Masmoudi S Kalay E Belyantseva IA Mosrati MA Collin RW Riazuddin S Hmani-Aifa M Venselaar H Kawar MN Tlili A van der Zwaag B Khan SY Ayadi L Riazuddin SA Morell RJ Griffith AJ Charfedine I Caylan R Oostrik J Karaguzel A Ghorbel A Riazuddin S Friedman TB Ayadi H Kremer H 《Nature genetics》2008,40(11):1335-1340
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İlknur Yıldız Ali Muzaffer Feyzioglu Sengul Besiktepe 《Journal of Natural History》2017,51(3-4):127-139
The zooplankton species Oithona davisae is indigenous to coastal areas of Japan and the China Seas. It has, however, successfully invaded many other coastal marine regions such as San Francisco Bay, the Mediterranean Sea, the North Sea and the Black Sea. It is transported most probably in ballast water tanks. This is the first report of O. davisae in the coastal regions of the southern Black Sea (Anatolian coast). Based on monthly plankton sampling at two stations (Sürmene Bay), the seasonal dynamics of O. davisae were investigated. The highest abundance occurred at the coastal station (49,761 ind. m?3) in December and in October at the offshore station (8896 ind. m?3). The egg-carrying copepod O. davisae is more abundant in September (4571 ind. m?3) at the coastal station and in August (952 ind. m?3) at the offshore station. Expansion of this invasive copepod along the Black Sea coasts is reported by another country also. According to our results this invasive species may replace its native congener, Oithona nana. It can be hypothesized that O. davisae is one of the key species for energy transfer to the upper level of the food web from the microbial loop, which has recently become important in the Black Sea. 相似文献
67.
从本文开始我们对(Ⅲ)m=0类二次系统的极限环问题作了一系统研究,按照其系数的各种不同情况分类讨论.本文考察l<1/2,01的情况,给出了极限环惟一性的一些结论,并指出有时在一个焦点外围可以存在两个极限环,同时分析了系统的拓扑结构的变化. 相似文献
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69.
Zusammenfassung Psoralenfütterung von Ratten bewirkt eine Vermehrung des Kupfergehaltes in der Milz und eine Verminderung in der Leber. In der Haut sind die Werte nicht einheitlich. 相似文献
70.