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排序方式: 共有95条查询结果,搜索用时 203 毫秒
1.
EA Dukhanina TI Lukyanova EA Romanova V Guerriero NV Gnuchev GP Georgiev DV Yashin LP Sashchenko 《Cell cycle (Georgetown, Tex.)》2015,14(22):3635-3643
PGRP-S (Tag7) is an innate immunity protein involved in the antimicrobial defense systems, both in insects and in mammals. We have previously shown that Tag7 specifically interacts with several proteins, including Hsp70 and the calcium binding protein S100A4 (Mts1), providing a number of novel cellular functions. Here we show that Tag7–Mts1 complex causes chemotactic migration of lymphocytes, with NK cells being a preferred target. Cells of either innate immunity (neutrophils and monocytes) or acquired immunity (CD4+ and CD8+ lymphocytes) can produce this complex, which confirms the close connection between components of the 2 branches of immune response. 相似文献
2.
The application of liquid membrane extraction to the recovery of lactic acid from model systems and fermentation media was investigated. An experimental study of the facilitated transport of lactic acid using ALIQUAT 336 as a mobile carrier in a stirred transfer cell is reported. The effect of stirring speed, initial lactic acid concentration, carrier concentration, and NaCl as a reagent in the acceptor phase are considered. (c) 1994 John Wiley & Sons, Inc. 相似文献
3.
Y. Markovska M. Geneva P. Petrov M. Boychinova I. Lazarova I. Todorov I. Stancheva 《Russian Journal of Plant Physiology》2013,60(5):623-632
The effects of EDTA application to heavy metal-polluted soil on phytoextraction of heavy metals, leaf anatomy, gas exchange parameters, enzyme activities of C4 carbon cycle, antioxidant defense, and active compounds of Tribulus terrestris L. were evaluated. The addition of EDTA to the soil polluted with Cd and Pb markedly increased dry weight and Pb, Zn, and Cd contents in shoots. Plants responded to the action of EDTA by an increased stomatal conductance, photosynthetic and transpiration rates, water use efficiency, chlorophyll and carotenoid contents. The activities of C4 carbon cycle enzymes simultaneously increased, thus concentrating CO2 for enhanced CO2 assimilation and providing NADPH for the antioxidant system. Antioxidants, such as ascorbate, reduced glutathione, and flavonoids, increased more in the shoots of T. terrestris after the addition of EDTA. The activities of guaiacol peroxidase, catalase, and the enzymes of the ascorbate-glutathione cycle enhanced significantly in the presence of EDTA. Increased activities of antioxidant enzymes suggest that they have some additive functions in the mechanism of metal tolerance. EDTA application lowered the activity of phenylalanine ammonia-lyase and the content of total phenols, MDA, hydrogen peroxide, dehydroascorbate, and lipid-soluble antioxidant capacity expressed as α-tocopherol. Increased levels of total radical-scavenging activity are in correspondence with the activity of water-soluble antioxidant compounds in T. terrestris tissues. The content of furostanol saponins protodioscin, prototribestin, and rutin increased as a result of EDTA addition. The results obtained allowed us to assume that applied EDTA reduced a negative heavy metal impact on puncture vine photosynthesis and antioxidant potential. 相似文献
4.
目的:探讨280例胃食管反流病(GERD)的分布特点及危险因素。方法:对临床诊断和胃镜确诊的280例GERD患者进行临床和风险因子相关性分析。结果:不论汉族还是维族,男性患者比例均明显高于女性;汉族患者高发年龄段早于维族患者(z=-2.939,P=0.003,);汉族和维族患者占反流性食管炎和Barrett食管比例分别为42.4%、81_3%及56.5%、18.8%,其中汉族患者Barrett食管比例较高(X2=14.358,P=0.000);肥胖、习惯性便秘、重体力活动者、饮食习惯不良在维族患者中的比例较高(P〈0.001)。结论:GERD与性别、年龄密切相关,男性多于女性,汉族患者发病年龄高峰旱于维族患者;汉族患者Barrett食管发生比例高于维族患者;肥胖、习惯性便秘、重体力活动、饮食习惯不良可能是GERD尤其是维族人群GERD的危险因素。 相似文献
5.
Sanz C Márquez M Perálvarez A Elouatik S Sepulcre F Querol E Lazarova T Padrós E 《The Journal of biological chemistry》2001,276(44):40788-40794
Single and multiple mutants of extracellular Glu side chains of bacteriorhodopsin were analyzed by acid and calcium titration, differential scanning calorimetry, and thermal difference spectrophotometry. Acid titration spectra show that the second group protonating with Asp(85) is revealed in E204Q in the absence of Cl(-) but is not observed in the triple mutant E9Q/E194Q/E204Q or in the quadruple mutant E9Q/E74Q/E194Q/E204Q. The results point to Glu(9) as the second group protonating cooperatively with Asp(85). Comparison of the apparent pK(a) of Asp(85) protonation in water and in the deionized forms and results of calcium titration suggest that cation-binding sites are of low affinity in the multiple Glu mutants. Like for deionized wild type bacteriorhodopsin, differential scanning calorimetry reveals a lack of the pretransition in the multiple mutants, whereas in E9Q it appears at lower temperature and with lower cooperativity. Additionally, at neutral pH the band at 630 nm arising from cation release upon temperature increase is absent for the multiple mutants. Based on these results, we propose the presence of two cation-binding sites in the extracellular region of bacteriorhodopsin having as ligands Glu(9), Glu(194), Glu(204), and water molecules. 相似文献
6.
Horowitz S Binion DG Nelson VM Kanaa Y Javadi P Lazarova Z Andrekopoulos C Kalyanaraman B Otterson MF Rafiee P 《American journal of physiology. Gastrointestinal and liver physiology》2007,292(5):G1323-G1336
Nitric oxide (.NO) generation from conversion of l-arginine to citrulline by nitric oxide synthase isoforms plays a critical role in vascular homeostasis. Loss of .NO is linked to vascular pathophysiology and is decreased in chronically inflamed gut blood vessels in inflammatory bowel disease (IBD; Crohn's disease and ulcerative colitis). Mechanisms underlying decreased .NO production in IBD gut microvessels are not fully characterized. Loss of .NO generation may result from increased arginase (AR) activity, which enzymatically competes with nitric oxide synthase for the common substrate l-arginine. We characterized AR expression in IBD microvessels and endothelial cells and its contribution to decreased .NO production. AR expression was assessed in resected gut tissues and human intestinal microvascular endothelial cells (HIMEC). AR expression significantly increased in both ulcerative colitis and Crohn's disease microvessels and submucosal tissues compared with normal. TNF-alpha/lipopolysaccharide increased AR activity, mRNA and protein expression in HIMEC in a time-dependent fashion. RhoA/ROCK pathway, a negative regulator of .NO generation in endothelial cells, was examined. The RhoA inhibitor C3 exoenzyme and the ROCK inhibitor Y-27632 both attenuated TNF-alpha/lipopolysaccharide-induced MAPK activation and blocked AR expression in HIMEC. A significantly higher AR activity and increased RhoA activity were observed in IBD submucosal tissues surrounding microvessels compared with normal control gut tissue. Functionally, inhibition of AR activity decreased leukocyte binding to HIMEC in an adhesion assay. Loss of .NO production in IBD microvessels is linked to enhanced levels of AR in intestinal endothelial cells exposed to chronic inflammation in vivo. 相似文献
7.
8.
Milka Elshishka Stela Lazarova Georgi Radoslavov Petar Hristov Vlada K. Peneva 《ZooKeys》2015,(511):25-68
The taxonomic position of two antarctic dorylaimid species Amblydorylaimus
isokaryon (Loof, 1975) Andrássy, 1998 and Pararhyssocolpus
paradoxus (Loof, 1975), gen. n., comb. n. are discussed on the basis of morphological, including SEM study, morphometric, postembryonic and sequence data of 18S rDNA and the D2-D3 expansion fragments of large subunit rDNA. The evolutionary trees inferred from 18S sequences show insufficient resolution to determine the assignment of the two species to particular families, moreover Pararhyssocolpus
paradoxus
gen. n., comb. n. (=Rhyssocolpus
paradoxus) previously regarded as a member of Nordiidae or Qudsianematidae, showed distant relationship both to Rhyssocolpus
vinciguerrae and Eudorylaimus spp. The phylogram inferred from 28S sequences revealed that Amblydorylaimus
isokaryon is a member of a well-supported group comprised of several Aporcelaimellus spp., while, no close relationships could be revealed for the Pararhyssocolpus
paradoxus
gen. n., comb. n. to any nematode genus. On the basis of molecular data and morphological characteristics, some taxonomic changes are proposed. Amblydorylaimus
isokaryon is transferred from family Qudsianematidae to family Aporcelaimidae, and a new monotypic genus Pararhyssocolpus
gen. n. is proposed, attributed to Pararhyssocolpidae
fam. n. The diagnosis of the new family is provided together with emended diagnosis of the genera Amblydorylaimus and Pararhyssocolpus
gen. n. Data concerning distribution of these endemic genera in the Antarctic region are also given. 相似文献
9.
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
10.
刘英姿邵培双王东升遆丹阳王锐 《现代生物医学进展》2011,11(18):3485-3487
目的:探讨烟龄≥15年,日吸烟量≥15支的无症状男性吸烟者的肺功能改变情况。方法:选择男性无症状吸烟者190人及非吸烟者180人,进行肺功能测定,并比较两组人群的肺功能改变情况。结果:吸烟组与非吸烟组比较,肺活量(VC)、用力肺活量(FVC)、第1秒用力呼气容积(FEV1)、Tiffeneau 1秒率(FEV1/VC)结果改变不明显,而Gaensler 1秒率(FEV1/FVC)、最大分钟通气量(MVV)、用力呼气50%肺活量的呼气流量(FEF50%)、用力呼气75%肺活量的呼气流量(FEF75%)、呼出25%~75%肺活量时的平均流量(FEF25%~75%)、肺一氧化碳弥散量(DLCO)结果均有显著降低,有统计学意义。结论:通过对无症状吸烟人群肺功能测定结果进行分析。发现有些吸烟者虽无临床症状,但已经出现了小气道及肺弥散功能的损伤,提醒吸烟者应早期戒烟,关爱自身健康,净化生存环境,提高生活质量。 相似文献