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SYNOPSIS A method is described for the electrophoretic analysis of proteins or RNAs from individual amebae. The method is based on fluorographic autoradiography of semi-micro polyacrylamide gels in which [35S]methionine or [3H]uridine materials from single cells have been subjected to electrophoresis. The method is more sensitive and provides better resolution than previous methods for single cells. It is suitable, also, for quantitation of the separated components.  相似文献   
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小菜蛾生物学的研究:生活史、世代数及温度关系   总被引:10,自引:0,他引:10  
小菜娥(Plutella xylostella L.)广泛分布干世界各地。在杭州郊区,近年来上升为最重要的十字花科害虫。为害猖獗时可减产3—5成。 1973—1974年的研究表明,在杭州实验室条件下,小菜蛾一年可发生9—14代,世代重叠。在田间,各个季节都能见到四种虫态,没有越冬滞育现象。 成虫产卵期可以近于或长于下一代的幼期历期。这是世代重叠的一个重要因素。九月份达到世代重叠高峰,每旬七代重叠,而从整个九月份看,可有八代重叠。 在杭州室内最适气温条件下,发生一代仅需9—10天;而冬天完成一代却要110天。卵、幼虫和蛹的全年残存率分别为75.62%,80.21%和93.60%。 幼期历期与日平均温度间的曲线迴归方程为Y=1997X-2.0625,Y=4345X-2.0258,Y=2427X-2.0025。  相似文献   
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Summary

The larval, megalopal and early juvenile stages of Pagurus granosimanus are described, illustrated and compared with other North Pacific species of the genus. Morphologically, the zoeae of P. granosimanus appear most similar to the Japanese P. brachiomastus in the majority of characters, but share the endopodal setation of the third maxilliped with a second Japanese species, P. pectinatus. The megalopae of P. granosimanus are unlike those of other North Pacific species in having 5+5 marginal setae on the telson, rather than the customary 4+4, or less frequent 3+3. Comparison of juvenile characters is limited to pleopodal changes among the regional species for which data are available. P. granosimanus is unusual in undergoing complete pleopodal loss at the second crab stage with return of left pleopods in the fourth stage.  相似文献   
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We studied hybridization between the diploid Centaurea pseudophrygia and the tetraploid C. jacea by performing crossing experiments and screening natural populations using flow cytometry. The experiments confirm that the studied species exhibit strong reproductive isolation. Interspecific hybrids were formed at a low frequency, including triploids (originating from reduced gametes) and tetraploids (involving unreduced gametes of the diploids). In contrast, hybrids were almost absent among seeds and adult plants of natural mixed populations and among the offspring from experimental pollinations with a mixture of pollen of both ploidy levels. We found that mixed pollination is an important mechanism for preventing hybridization between plants of different ploidy levels and sustaining the reproduction of the tetraploids. A mentor effect (induced selfing in the presence of pollen of different ploidy levels) was observed in both diploids and tetraploids, reinforcing the reproductive isolation between cytotypes. Higher ploidy levels (pentaploid, hexaploid) involving unreduced gametes of the tetraploid species were identified. Notably, pentaploids were discovered for the first time in Centaurea sect. Jacea. © 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 104 , 93–106.  相似文献   
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Luciobliviidae, a new family in the superfamily Gammaroidea (Amphipoda: Crustacea), is described on the basis of species in the genus Lucioblivio gen. nov. from subterranean waters of Japan. Mesogammaridae Bousfield, 1977 is rediagnosed; Octopupilla gen. nov. from subterranean waters of Japan is described and Eoniphargus (Uéno, 1955) from subterranean waters of Japan and Korea is included. The members of Lucioblivio , Octopupilla and Eoniphargus share several characters, including reduced eyes, a setose body, reduced coxae, feeble appendages and pedunculate coxal gills. To elucidate the phylogeny of the three genera among others, a sequence analysis of the 28S rRNA gene was conducted for 14 species in six families, including the three genera, from the superfamilies, Gammaroidea, Crangonyctoidea and Hadzioidea. The tree from a neighbour-joining analysis and the strict consensus tree from a maximum-parsimony analysis indicate monophyly of Mesogammaridae. Luciobliviidae is embedded within a clade of taxa belonging to the superfamily Gammaroidea. These results and the occurrence of gammarid-type calceoli in species of the new family indicate that Luciobliviidae should be placed within the superfamily Gammaroidea. © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 149 , 643–670.  相似文献   
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Sixty-five colistin-resistant Enterobacterales isolates recovered from different clinical specimens were analyzed. The strains were collected in 12 hospitals all over Poland within a period of nine months. Strains were analyzed for eight genes from the mcr family. The presence of mcr-1 gene was detected in three Escherichia coli strains. The 45/65 isolates were identified as ESBL producers. CTX-M-1-like enzymes were the most common ESBLs (n = 40). One E. coli and seven Klebsiella pneumoniae strains produced carbapenemases, with the NDM being produced by five isolates. Among all the strains tested, four and five were resistant to new drugs meropenem/vaborbactam and ceftazidime/avibactam, respectively.  相似文献   
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Silkworm pupae have much potential and many applications as a natural medicine to promote human health. However, their chemical components have not been fully characterized or understood. HPLC analysis was conducted to determine the content ratio (%) of individual amino acids in total protein of the pupae. It showed that glutamic acid (18.3%), histidine (14.6%) and alanine (10.2%) are the most common amino acids in silkworm pupae. Fatty acid composition of silkworm pupae oil was revealed by high‐pressure liquid chromatography and gas chromatography – mass spectroscopy analyses. They contain a high ratio of essential fatty acids, [α‐linolenic acid (ω‐3 fatty acid]+ linoleic acid) (49.0%), and also contain non‐essential fatty acids, oleic acid (19.9%), palmitoleic acid (2.5%), palmitic acid (19.7%), stearic acid (8.6%), and eicosapentaenoic acid (EPA) (0.3%). In addition, they also contain antioxidants, quercetin diglucoside and nutritionally important riboflavin (vitamin B2). This study suggests that silkworm pupae are a nutritionally valuable food product and are applicable as cosmetic components with essential amino acids, essential fatty acids, antioxidants and vitamins. The animal experiment showed that alcohol dehydrogenase (ADH) activity was significantly higher in the liver of mice orally administered with 0.5 mg/mL of silkworm extract and alcohol than with commercial Dawn808? and alcohol, indicating that silkworm pupae extracts have alcohol detoxification activity.  相似文献   
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