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31.
32.
目的:探讨激活多巴胺Ⅰ类受体(DR1)对氧化型低密度脂蛋白(ox-LDL)诱导的人单核细胞(THP-1)分泌一氧化氮/一氧化氮合酶(NO/NOS)的影响及可能机制。方法:THP-1细胞经佛波酯PMA诱导分化,分为正常对照组(control),氧化型低密度脂蛋白处理组(ox-LDL),DR1激动剂干预组(SKF),DR1阻断剂干预组(SCH),ERK阻断剂干预组(PD98059);应用油红O染色法鉴定泡沫细胞;硝酸还原法检测NO、NOS的变化情况;免疫荧光和Western blot检测各组细胞蛋白表达情况。结果:ox-LDL刺激48 h可形成泡沫细胞;DR1在THP1细胞上表达,ox-LDL刺激后,DR1蛋白表达降低(P<0.01);激活DR1受体能够明显抑制由ox-LDL引起的NO、iNOS增多(P<0.01);在MAPK阻断剂PD98059存在的情况下,SKF的作用部分丧失。结论:激活DR1受体可抑制ox-LDL引起的THP-1细胞NO的大量产生,此过程可能由ERK信号通路所介导。 相似文献
33.
Maternal protein restriction during gestation and lactation in the rat results in increased brain levels of kynurenine and kynurenic acid in their adult offspring 下载免费PDF全文
34.
Islam Md. Rashedul Trivedi Pankaj Palaniappan Pitchai Reddy M. S. Sa Tongmin 《World journal of microbiology & biotechnology》2009,25(6):1115-1117
The present study was undertaken to observe the effects of chemical fertilizers and compost amendments on microbial community
structure in rice based cropping system under long term fertilizer application experiment. Changes in microbial community
structure assessed by the relative abundance of fatty acid methyl ester (FAME) profiles revealed that compost amendments led
to promoting the abundance of Gram-positive bacterial FAMEs. Multivariate analysis of FAME profiles separated the treatments
primarily on the basis of the amount of added compost. A link between different fertilizer application treatment and soil
microbial components was tentatively established, but it needs to be verified in further studies. 相似文献
35.
Sonia Saïd Jean‐Michel Gaillard Olivier Widmer François Débias Gilles Bourgoin Daniel Delorme Céline Roux 《Oikos》2009,118(9):1299-1306
Spatial distribution in mammals, and thereby home range size, is influenced by many different factors including body size, sex, age, reproductive status, season, availability of forage, availability of water, fragmentation of landscape, trophic level and intra- and inter-specific competition. Using linear mixed models, we looked for factors shaping the variation in size of spring-summer and winter home ranges for 51 radio-collared adult female roe deer at Trois Fontaines forest, Champagne–Ardenne, France (1996–2005). Home range size of females was larger in winter than in spring–summer, decreased with age, and decreased with increasing quality. Females in low quality areas adjusted the size of their home range to include more patches of habitat so that all female deer obtained similar amounts of food resources (total biomass of 6.73±2.34 tons (mean±SE) for each home range). Such adjustments of home range size in response to patchiness of resources led to marked between-female variation in home range size. Our results demonstrate that roe deer females have different tactics of habitat use according to spatial variations in habitat quality so that females get similar food resources in highly productive environments such as the Trois Fontaines forest. 相似文献
36.
Odaert B Saïda F Aliprandi P Durand S Créchet JB Guerois R Laalami S Uzan M Bontems F 《The Journal of biological chemistry》2007,282(3):2019-2028
The RegB endoribonuclease participates in the bacteriophage T4 life cycle by favoring early messenger RNA breakdown. RegB specifically cleaves GGAG sequences found in intergenic regions, mainly in translation initiation sites. Its activity is very low but can be enhanced up to 100-fold by the ribosomal 30 S subunit or by ribosomal protein S1. RegB has no significant sequence homology to any known protein. Here we used NMR to solve the structure of RegB and map its interactions with two RNA substrates. We also generated a collection of mutants affected in RegB function. Our results show that, despite the absence of any sequence homology, RegB has structural similarities with two Escherichia coli ribonucleases involved in mRNA inactivation on translating ribosomes: YoeB and RelE. Although these ribonucleases have different catalytic sites, we propose that RegB is a new member of the RelE/YoeB structural and functional family of ribonucleases specialized in mRNA inactivation within the ribosome. 相似文献
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38.
A new needle nematode, Longidorus carniolensissp. n., recovered from the soil around the roots of grapevine Vitis vinifera L. from Slovenia, is described and illustrated. Longidorus carniolensisis an amphimictic species, characterised by females with a moderately long (L=5.6-8.2 mm) and plump (a=51-72.4, ave. 66.3) body, assuming a spiral to C-shape when heat relaxed. Head region continuous, anteriorly almost flat, lip region 23-25 μm wide; guiding ring situated posteriorly (42-47 μm, 43-50 μm in males), odontostyle long (ave. 146.6 (136-157) μm); pharyngeal glands with normal location, their nuclei of approximately equal size; tail bluntly conoidal to almost hemispherical. Males abundant, spicules slender and long (122-145 μm), ventromedian supplements 13-17, irregularly spaced, preceded by an adanal pair. Four juvenile stages present, the first stage juvenile with bluntly conoidal tail. Codes for identifying the new species when using the key by Chen et al. (1997) are: A 56, B 4, C 4, D 1, E 4, F 35, G 1, H 1, I 2. The new species is morphologically the most similar to Longidorus poessneckensis Altherr, 1974, Longidorus macrosoma Hooper, 1961, Longidorus caespiticola Hooper, 1961, Longidorus helveticus Lamberti et al., 2001, Longidorus macroteromucronatus Altherr, 1974, Longidorus pius Barsi & Lamberti, 2001, Longidorus raskii Lamberti & Agostinelli, 1993, Longidorus kheirii Pedram et al. 2008, Longidorus silvae Roca, 1993, Longidorus iuglandis Roca et al., 1985, Longidorus vinearum Bravo & Roca, 1995 and Longidorus major Roca & d'Erico, 1987, but differs from these species either by the body and odontostyle length, position of guide ring, head region and tail shape or the shape of the first stage juvenile tail. Sequence data from the D2-D3 region of the 28S rDNA distinguishes this new species from other speciesof the genus Longidorus with known sequences. Relationships of Longidorus carniolensissp. n. with other Longidorus species based on analysis of this DNA fragment and morphology are discussed. 相似文献
39.
A simple, sensitive and rapid flow injection analysis (FIA) method with resonance light scattering (RLS) was described for the determination of propafenone (PPF). The method was based on the ion‐association reaction of 12‐tungstophosphoric acid (TP) with propafenone. In pH 1.0 acidic medium, TP reacted with PPF to form an ion‐associate complex, which resulted in a significant enhancement of RLS intensity. The maximum scattering peak was located at 340 nm, the RLS intensity was proportional to the concentration of PPF in the range 0.003–9.0 µg/mL, and the detection limit (3σ) of 1.0 ng/mL was obtained at a sampling rate of 60 samples/h. The feasible reaction conditions and FIA parameters for the system were optimized. The method proposed in this paper shows satisfactory reproducibility with a relative standard deviation (RSD) of 2.1% for 10 successive determinations of 2.0 µg/mL PPF. The present method had been successfully applied to the determination of PPF in serum samples and pharmaceutical samples. The results obtained were in agreement with the method used in the Chinese Pharmacopoeia. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
40.
Saša N. Malkov Miodrag V. Živković Miloš V. Beljanski Srđan Đ. Stojanović Snežana D. Zarić 《The protein journal》2009,28(2):74-86
Using the data from Protein Data Bank the correlations of primary and secondary structures of proteins were analyzed. The
correlation values of the amino acids and the eight secondary structure types were calculated, where the position of the amino
acid and the position in sequence with the particular secondary structure differ at most 25. The diagrams describing these
results indicate that correlations are significant at distances between −9 and 10. The results show that the substituents
on Cβ or Cγ atoms of amino acid play major role in their preference for particular secondary structure at the same position
in the sequence, while the polarity of amino acid has significant influence on α-helices and strands at some distance in the
sequence. The diagrams corresponding to polar amino acids are noticeably asymmetric. The diagrams point out the exchangeability
of residues in the proteins; the amino acids with similar diagrams have similar local folding requirements.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献