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排序方式: 共有287条查询结果,搜索用时 31 毫秒
31.
I. K. Lopatin 《Entomological Review》2006,86(6):662-669
Smaragdina schereri sp. n., Chrysolina jiangi sp. n., Ch. geae sp. n., Ch. gansuica sp. n., Sclerophaedon daccordii sp. n., Neophaedon sichuanicus sp. n., Oreomela inflata sp. n., Xingeina nigrolucens sp. n., Shaira hemipteroides sp. n. and Calomicrus atroviridis sp. n. from Sichuan, Gansu, and Yunnan provinces of China are described. Types of the new species are deposited in the Zoological Institute, Russian Academy of Sciences, St. Petersburg. 相似文献
32.
Lopatin DE Jaramillo E Edwards CA Van Poperin N Combs A Shelburne CE 《FEMS microbiology letters》1999,181(1):9-16
We previously reported an association between elevated serum antibody titers to the 90-kDa human heat shock protein (Hsp90), periodontal health and colonization by Porphyromonas gingivalis. In this study, we examined the cellular localization of the Hsp90 homologue of P. gingivalis. Cultures of P. gingivalis were heat-stressed (45 degrees C) and examined for localization of the Hsp90 homologue. Heat stress induced a 4-5-fold increase in anti-Hsp90 antibody reactivity over that of the unstressed controls. Western blot analysis revealed two bands (44 and 68 kDa) that reacted with anti-Hsp90 antibodies. The 68-kDa band was heat-inducible, while the 44-kDa band was not. Immunogold staining revealed that the Hsp90 homologue localized principally to the membrane and extracellular vesicles. Subcellular fractionation confirmed that the Hsp90 homologue was primarily membrane-associated. 相似文献
33.
Bodrova IV Dobrotin VE Kulakova LA Fominykh EV Pokoziĭ IIu Lopatin AS 《Vestnik rentgenologii i radiologii》2012,(1):4-8
The paper deals with computed tomography (CT) diagnosis of Eustachian tube dysfunction. A functional multislice spiral (MS) CT protocol has been first elaborated for the Eustachian tube. Twenty-three patients with unilateral conductive hearing loss and Eustachian tube dysfunction were examined. The normal functional anatomy of the Eustachian tube was evaluated on the side without evidence of pathology in 23 patients. Functional MSCT showed that the cartilaginous portion of the Eustachian tube opened partially and closed completely in 9 patients. Ten patients were found to have steady changes in the cartilaginous portion of the Eustachian tube. The developed method could confirm the cause of conductive hearing loss and optimally define a treatment policy. 相似文献
34.
The effect of mineral particulate matter on the population of bacterioplankton, its aggregation, and productive characteristics was studied in model experiments with different concentrations of particulate kaolin and the same concentration of organic substance (sodium humate). It was found that the presence of mineral particulate matter stimulated the aggregation of bacterioplankton, improved bacterial production, and extended the productive period of bacterioplankton. The integral specific production of aggregated bacterioplankton was higher than that of free-swimming bacterioplankton. The energy metabolic coefficient K
2 of bacterioplankton in the presence of mineral particulate matter was higher than in its absence. 相似文献
35.
I. K. Lopatin 《Entomological Review》2014,94(3):397-407
New species of the subfamilies Megalopodinae (Temnaspis humerosa sp. n.), Chrysomelinae [Chrysolina furialis sp. n., Ch. oxanae sp. n., Ch. pingchuana sp. n., Oreomelina (Oreomelina) obtusa sp. n., O. (Oreomelina) splendens sp. n. from Sichuan], and Galerucinae (Liroëtis obliquevirgata sp. n. from Sichuan, Hyphaenia lutescens sp. n. from Chongqing, H. potanini sp. n. from Sichuan, and H. kabaki sp. n. from Shaangxi) are described. 相似文献
36.
Carrier Transport and Recombination in Efficient “All‐Small‐Molecule” Solar Cells with the Nonfullerene Acceptor IDTBR
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Ru‐Ze Liang Maxime Babics Victoria Savikhin Weimin Zhang Vincent M. Le Corre Sergei Lopatin Zhipeng Kan Yuliar Firdaus Shengjian Liu Iain McCulloch Michael F. Toney Pierre M. Beaujuge 《Liver Transplantation》2018,8(19)
Reaching device efficiencies that can rival those of polymer‐fullerene Bulk Heterojunction (BHJ) solar cells (>10%) remains challenging with the “All‐Small‐Molecule” (All‐SM) approach, in part because of (i) the morphological limitations that prevail in the absence of polymer and (ii) the difficulty to raise and balance out carrier mobilities across the active layer. In this report, the authors show that blends of the SM donor DR3TBDTT (DR3) and the nonfullerene SM acceptor O‐IDTBR are conducive to “All‐SM” BHJ solar cells with high open‐circuit voltages (VOC) >1.1 V and PCEs as high as 6.4% (avg. 6.1%) when the active layers are subjected to a post‐processing solvent vapor‐annealing (SVA) step with dimethyl disulfide (DMDS). Combining electron energy loss spectroscopy (EELS) analyses and systematic carrier recombination examinations, the authors show that SVA treatments with DMDS play a determining role in improving charge transport and reducing non‐geminate recombination for the DR3:O‐IDTBR system. Correlating the experimental results and device simulations, it is found that substantially higher BHJ solar cell efficiencies of >12% can be achieved if the IQE and carrier mobilities of the active layer are increased to >85% and >10?4 cm2 V?1 s?1, respectively, while suppressing the recombination rate constant k to <10?12 cm3 s?1. 相似文献
37.
The initial steps in taste and olfaction result from the activation by
chemical stimuli of taste receptor cells (TRCs) and olfactory receptor
neurons (ORNs). In parallel with these two pathways is the chemosensitive
trigeminal pathway whose neurons terminate in the oral and nasal cavities
and which are activated by many of the same chemical stimuli that activate
TRCs and ORNs. In a recent single unit study we investigated the responses
of rat chorda tympani and glossopharnygeal neurons to a variety of
bitter-tasting alkaloids, including nicotine, yohimbine, quinine,
strychnine and caffeine, as well as capsaicin, the pungent ingredient in
hot pepper. Here we apply many of these same compounds to cultured rat
trigeminal ganglion (TG) neurons and measure changes in intracellular
calcium [Ca2+]i to determine whether TG neurons will respond to these same
compounds. Of the 89 neurons tested, 34% responded to 1 mM nicotine, 7% to
1 mM caffeine, 5% to 1 mM denatonium benzoate, 22% to 1 mM quinine
hydrochloride, 18% to 1 mM strychnine and 55% to 1 microM capsaicin. These
data suggest that neurons from the TG respond to the same bitter-tasting
chemical stimuli as do TRCs and are likely to contribute information sent
to the higher CNS regarding the perception of bitter/irritating chemical
stimuli.
相似文献
38.
Diffusional and Electrical Properties of T-Tubules Are Governed by Their Constrictions and Dilations
Cardiac t-tubules (TTs) form a network of complex surface membrane invaginations that is essential for proper excitation-contraction coupling. Although electron and optical microscopy studies provided a wealth of important information about the structure of TTs, assessing their functional properties remains a challenge. In this study, we investigated the diffusional accessibility of TTs in intact isolated adult mouse ventricular myocytes using, to our knowledge, a novel fluorescence-based assay. In this approach, a small part of TTs is first locally filled with fluorescent dextran and then its diffusion out of TTs is monitored after rapid removal of extracellular dextran. In normal cells, diffusion of 3 kDa dextran is characterized by an average time constant of 3.9 ± 1.2 s with the data ranging from 1.8 to 10.5 s. The data are consistent with essentially free diffusion of dextran in TTs although measurable contribution of binding is also evident. TT fluorescence is abolished in cells treated with high concentration of formamide or after hyposmotic stress. Importantly, the assay we use allows for quantitative, repetitive measurements of subtle dynamic changes in TT structure of the same cell that are not possible to observe with other approaches. In particular, dextran diffusion rate decreases two-to-threefold during cell swelling, suggesting significant structural remodeling of TTs. Computer modeling shows that diffusional accessibility and electrical properties of TTs are primarily determined by the constrictions and dilations of individual TTs and that, from a functional perspective, TTs cannot be considered as a network of cylinders of the same average diameter. Constriction/dilation model of cardiac TTs is in a quantitative agreement with previous high-resolution microscopy studies of TT structure and alternative measurements of diffusional and electrical time constants of TTs. The data also show that the apparent electrical length constant of cardiac TTs is likely several-fold smaller than that estimated in earlier studies. 相似文献
39.
The histological effect on and stress response of post juvenile Clarias gariepinus exposed to Qua Iboe crude oil and rig wash were investigated. Fish weighing 60–90 g and measuring 16–18 cm were exposed for 7–28 days to 8.00 ml?1 Qua Iboe crude oil and 0.0018 ml–1 rig wash, both being 0.1 of the 96 hr LC50. Blood samples of C. gariepinus were collected every seven days and evaluated for stress by measuring cortisol concentration. The gills and liver were studied and scored for Gill Alteration Index (GAI) and Hepatic Alteration Index (HAI), respectively. There was an increase in cortisol level up to the 7th and 14th day among the group exposed to Qua Iboe crude oil, with a decrease on the 21st and 28th day. The rig wash group increased in cortisol level up to the 7th day and decreased slightly on the 14th day, after which the trend became irregular. The toxic effects of the Qua Iboe crude oil and rig wash were time dependent, as shown by the histopathological alteration index (HAI) of gill and liver. After 28 days of exposure, the gills had irreparable damage due to high frequency of cellular necrosis and degeneration, whereas the liver had from moderate to severe damage due to the high frequency of cellular degeneration and inflammation. Qua Iboe crude oil and rig wash are both toxic to C. gariepinus, therefore their indiscriminate discharge to the environment must be discouraged. 相似文献
40.