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91.
Guowen Duan Robert B. Saint Chris A. Helliwell Carolyn A. Behm Peter M. Waterhouse Karl H. J. Gordon 《Transgenic research》2010,19(6):1121-1128
Drosophila melanogaster, along with all insects and the vertebrates, lacks an RdRp gene. We created transgenic strains of Drosophila melanogaster in which the rrf-1 or ego-1 RdRp genes from C. elegans were placed under the control of the yeast GAL4 upstream activation sequence. Activation of the gene was performed by crossing
these lines to flies carrying the GAL4 transgene under the control of various Drosophila enhancers. RT–PCR confirmed the successful expression of each RdRp gene. The resulting phenotypes indicated that introduction
of the RdRp genes had no effect on D. melanogaster morphological development. 相似文献
92.
Drew D Slotboom DJ Friso G Reda T Genevaux P Rapp M Meindl-Beinker NM Lambert W Lerch M Daley DO Van Wijk KJ Hirst J Kunji E De Gier JW 《Protein science : a publication of the Protein Society》2005,14(8):2011-2017
We describe a generic, GFP-based pipeline for membrane protein overexpression and purification in Escherichia coli. We exemplify the use of the pipeline by the identification and characterization of E. coli YedZ, a new, membrane-integral flavocytochrome. The approach is scalable and suitable for high-throughput applications. The GFP-based pipeline will facilitate the characterization of the E. coli membrane proteome and serves as an important reference for the characterization of other membrane proteomes. 相似文献
93.
94.
Hydrobiologia - Nursery areas of perch, Perca fluviatilis L., in the shallow coastal areas of the Baltic Sea are affected by increased water turbidity due to the ongoing eutrophication and other... 相似文献
95.
Legacy effects occur when particular species or their interactions with others have long-lasting impacts, and they are increasingly
recognized as important determinants of ecological processes. However, when such legacy effects have been explicitly explored,
they most often involve the long-term direct effects of species on systems, as opposed to the indirect effects. Here, we explore
how a legacy of small mammal exclusion on the abundance of a shrub, bush lupine (Lupinus arboreus), influences the abundance of a native land snail (Helminthoglypta arrosa) in coastal prairie and dune habitats in central California. The factors that limit populations of land snails are very poorly
known despite the threats to the persistence of this group of species. In grasslands, prior vole (Microtus californicus) exclusion created long-lasting gains in bush lupine abundance, mediated through the seedbank, and was associated with increased
snail numbers (10×) compared to control plots where mammals were never excluded. Similar plots in dune habitat showed no difference
in snail numbers due to previous mammal exclusion. We tested whether increased competition for food, increased predation,
and/or lower desiccation explained the decline in snail numbers in plots with reduced lupine cover. Tethering experiments
supported the hypothesis that voles can have long-lasting impacts as ecosystem engineers, reducing woody lupine habitat required
for successful aestivation by snails. These results add to a growing list of studies that have found that non-trophic interactions
can be limiting to invertebrate consumers. 相似文献
96.
Behm DG Button DC Barbour G Butt JC Young WB 《Journal of strength and conditioning research / National Strength & Conditioning Association》2004,18(2):365-372
The objective of this study was to investigate whether a warm-up consisting of a series of maximal contractions would augment the force and activation of subsequent leg extensor contractions. Both voluntary and evoked isometric contractions were tested to determine the mechanisms underlying the response. Nine subjects were tested for twitch, tetanic, submaximal (30%), and maximal voluntary contractile (MVC) properties before and after (1, 5, 10, and 15 minutes) one to three 10-second MVCs. MVC force either did not change following 1-2 MVCs or was depressed at 10 and 15 minutes after 3 MVCs. MVC activation was decreased (4.4-6.9%) throughout recovery, whereas submaximal contractions were minimally affected. Although overall, twitches were potentiated (15.5-19.8%) posttest, 3 MVCs had significantly greater twitch potentiation than 1 or 2 MVCs at 5 and 10 minutes. Results suggest that voluntary and evoked contractions respond differently to prior 10-second MVCs. In the present study, a warm-up routine of 1-3 MVCs of a 10-second duration did not enhance subsequent voluntary performance. 相似文献
97.
Yuan Ma Yanjiao Ma Guk‐Tae Kim Thomas Diemant Rolf Jürgen Behm Dorin Geiger Ute Kaiser Alberto Varzi Stefano Passerini 《Liver Transplantation》2019,9(43)
Herein, a Mn‐based metal–organic framework is used as a precursor to obtain well‐defined α‐MnS/S‐doped C microrod composites. Ultrasmall α‐MnS nanoparticles (3–5 nm) uniformly embedded in S‐doped carbonaceous mesoporous frameworks (α‐MnS/SCMFs) are obtained in a simple sulfidation reaction. As‐obtained α‐MnS/SCMFs shows outstanding lithium storage performance, with a specific capacity of 1383 mAh g?1 in the 300th cycle or 1500 mAh g?1 in the 120th cycle (at 200 mA g?1) using copper or nickel foil as the current collector, respectively. The significant (pseudo)capacitive contribution and the stable composite structure of the electrodes result in impressive rate capabilities and outstanding long‐term cycling stability. Importantly, in situ X‐ray diffraction measurements studies on electrodes employing various metal foils/disks as current collector reveal the occurrence of the conversion reaction of CuS at (de)lithiation process when using copper foil as the current collector. This constitutes the first report of the reaction mechanism for α‐MnS, eventually forming metallic Mn and Li2S. In situ dilatometry measurements demonstrate that the peculiar structure of α‐MnS/SCMFs effectively restrains the electrode volume variation upon repeated (dis)charge processes. Finally, α‐MnS/SCMFs electrodes present an impressive performance when coupled in a full cell with commercial LiMn1/3Co1/3Ni1/3O2 cathodes. 相似文献
98.
Willardson JM Behm DG Huang SY Rehg MD Kattenbraker MS Fontana FE 《Journal of strength and conditioning research / National Strength & Conditioning Association》2010,24(12):3415-3421
The purpose of this study was to compare the activation of the rectus abdominis (RA), external oblique abdominis (EO), lower abdominal stabilizers (LASs), and lumbar erector spinae (LES) during performance of 3 traditional trunk exercises vs. exercise on the Ab Circle device. Surface electromyography was used to assess 12 subjects (6 men, 6 women) for 6 exercise conditions, including: abdominal crunch, side bridge, quadruped, and Ab Circle levels 1-3. For the RA, the abdominal crunch elicited significantly greater activity vs. the Ab Circle level 1, and the side bridge elicited significantly greater activity vs. the Ab Circle levels 1 and 2. For the EO, the side bridge elicited significantly greater activity vs. the quadruped. No significant differences were noted between conditions for the LASs. For the LES, the side bridge and quadruped elicited significantly greater activity vs. the abdominal crunch. The results of this study indicate that the anterior, posterior, and lateral trunk musculature can be activated to similar or even greater levels by performing the 3 traditional trunk exercises vs. the Ab Circle. This was particularly evident for the side bridge exercise, which elicited significantly greater activity of the RA vs. the Ab Circle levels 1 and 2, and elicited similar activity of the EO, LASs, and LES at all 3 Ab Circle levels. 相似文献
99.
C J Rule M J Hanisch C A Behm F L Bygrave 《International journal for parasitology》1991,21(3):353-355
Respiration by mitochondria isolated from the livers of sheep following infection up to 15 weeks with F. hepatica was measured with the respiratory substrates pyruvate (plus malate) and succinate in the absence and presence of ADP; the rates were compared with those obtained by mitochondria isolated from livers of uninfected sheep. It was found that respiration supported by both substrates in mitochondria isolated from the left lobe but not the middle lobe of 4-week infected sheep exhibited abnormalities such that the acceptor control ratios were only marginally above one. Some, but not total, recovery was seen in the later stages of infection. The aberrant respiratory behaviour is similar to that observed with infected rats. 相似文献
100.
R Behm B Gerber J O Habeck C Huckstorf K Rückborn C Zingler 《Physiologia Bohemoslovaca》1989,38(3):207-213
To explore the role of arterial chemoreceptors, the effect of hypobaric hypoxia on urinary sodium excretion and systolic blood pressure was investigated in conscious spontaneously hypertensive rats (SHR) with carotid body denervation (CBD) or after sham-operation (SO). Denervation of the carotid bodies was performed by section of the carotid sinus nerves. Exposure to hypobaric hypoxia equivalent to high altitude of 4000 m led to a more pronounced decrease in systolic blood pressure in CBD-rats than in SO-rats. The pattern of urinary sodium excretion observed on the first two days of hypoxia in both groups was not affected by the chemodenervation. It is being suggested that arterial chemoreceptors do not play a critical role in blood pressure and natriuretic responses to hypobaric hypoxia in conscious SHR. 相似文献