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1.
лсследовалось действие на микро?лору поверхности корней пшеницы, выращиваемой в питательных растворах, внекорневой подкормки следующими веществами: питательные вещества, абсорбируемые и метаболиэируемые растением (мочевина, ?ос?ат), регуляеоры роста (2-метил-4-хлор?еноксиук сусная кислота и 2,4-дичлор?еноксиуксус ная кислота) и антибиотики (хлортетрациклин и хлорам?еникол). Действие этих веществ проявлялось более выраэительно на росте корней, чем на росте листьев. Не наблюдалось корреляции между действием на рост пшеницы и числом микроограниэмов на корнях. Число бактерий на корнях понижалось после применения трийодбенэойной кислоты, а в особенности -хлорам?еникола. В остальных случаях наблюдалось повышение числа бактерий, наиболее эначительное после нанесения на листья мочевины. Обнаружепа обратная эависимость между действием этих веществ на бактерии и на грибки: после нанесения па лист трийодбенэойрой кислоты или хлорам?еникола число грибков на корнях было гораэдо больше, после обработки листьев мочевиной ниже. Обработка листьев трийодбенэойной кислотой и хлорам?ениколом отражалась на качестиенных иэменениях состава бактерийной ?лоры поверхрости корней, а именно на составе мор?ологических и тро?ических групп и групп с раэличными ?иэиологическими особенностями. Равным обраэом, были отмечены количественные иэменения в корневых выделениях -в особенности после обработки хлорам?ениколом. Обсуждаются воэможности применения внекорневой подкормки как средства контроля микро?лоры риэос?еры, а также вопросы, свяэанные с действием этого мероприятия на э??ект риэос?еры.  相似文献   

2.
Diabet. Med. 29, 1260-1267 (2012) ABSTRACT: Aims Evaluate dose-dependent effects of once-weekly dulaglutide, a glucagon-like peptide-1 analogue, on glycaemic control in patients with Type?2 diabetes treated with lifestyle measures with or without previous metformin. Methods This 12-week, double-blind, placebo-controlled, dose-response trial randomized 167 patients who were anti-hyperglycaemic medication-na?ve or had discontinued metformin monotherapy [mean baseline HbA(1c) 59?±?8 to 61?±?8?mmol/mol (7.6?±?0.7 to 7.8?±?0.8%)] to once-weekly injections of placebo or dulaglutide (0.1, 0.5, 1.0 or 1.5?mg). Results A significant dose-dependent reduction in HbA(1c) (least squares mean?±?se) was observed across doses (P?相似文献   

3.
A recombinant enzyme from Lysinibacillus fusiformis was expressed, purified, and identified as an oleate hydratase because the hydration activity of the enzyme was the highest for oleic acid (with a k (cat) of 850?min(-1) and a K (m) of 540?μM), followed by palmitoleic acid, γ-linolenic acid, linoleic acid, myristoleic acid, and α-linolenic acid. The optimal reaction conditions for the enzymatic production of 10-hydroxystearic acid were pH 6.5, 35?°C, 4% (v/v) ethanol, 2,500?U ml(-1) (8.3?mg?ml(-1)) of enzyme, and 40?g l(-1) oleic acid. Under these conditions, 40?g l(-1) (142?mM) oleic acid was converted into 40?g l(-1) (133?mM) 10-hydroxystearic acid for 150?min, with a molar yield of 94% and a productivity of 16?g l(-1)?h(-1), and olive oil hydrolyzate containing 40?g l(-1) oleic acid was converted into 40?g l(-1) 10-hydroxystearic acid for 300?min, with a productivity of 8?g l(-1)?h(-1).  相似文献   

4.
The combination of gene therapy and virotherapy for cancer treatment has received close attention and has become a trend in the field of cancer biotherapy. A strategy called 'Cancer Targeting Gene-Viro-Therapy' (CTGVT) or 'Gene Armed Oncolytic Viral Therapy' (GAOVT) has been proposed, in which an antitumor gene is inserted into an oncolytic viral vector. In our previous study, a dual-regulated oncolytic adenovirus with enhanced safety for normal cells and strict liver cancer-targeting ability, designated Ad?enAFP?E1A?E1B (Δ55) (briefly Ad?enAFP?D55), was successfully constructed. In the current work, interleukin-24 (IL-24) and suppressor of cytokine signaling 3 (SOCS3) genes were packaged into Ad?enAFP?D55. The new constructs, Ad?enAFP?D55-(IL-24) and Ad?enAFP?D55-(SOCS3), showed improved tumoricidal activity in hepatoma cell lines compared with the oncolytic viral vector Ad?enAFP?D55. The co-administration of Ad?enAFP?D55-(IL-24) and Ad?enAFP?D55-(SOCS3) showed much better antitumor effect than Ad?enAFP?D55-(IL-24) or Ad?enAFP?D55-(SOCS3) alone both in vitro and in a nude mouse xenograft model. Moreover, our results also showed that blockade of the Jak/Stat3 pathway by Ad?enAFP?D55-(SOCS3) infection in HuH-7 cells could down-regulate some anti-apoptosis proteins, such as XIAP, Bcl-xL, and survivin, which might sensitize the cells to Ad?enAFP?D55-(IL-24)-induced apoptosis. These results indicate that co-administration of Ad?enAFP?D55-(IL-24) and Ad?enAFP?D55-(SOCS3) may serve as a candidate therapeutic approach for the treatment of liver cancer.  相似文献   

5.
Myeloid leukaemia factor 1 (MLF1) binds to 14-3-3 adapter proteins by a sequence surrounding Ser34 with the functional consequences of this interaction largely unknown. We present here the high-resolution crystal structure of this binding motif [MLF1(29-42)pSer34] in complex with 14-3-3ε and analyse the interaction with isothermal titration calorimetry. Fragment-based ligand discovery employing crystals of the binary 14-3-3ε/MLF1(29-42)pSer34 complex was used to identify a molecule that binds to the interface rim of the two proteins, potentially representing the starting point for the development of a small molecule that stabilizes the MLF1/14-3-3 protein-protein interaction. Such a compound might be used as a chemical biology tool to further analyse the 14-3-3/MLF1 interaction without the use of genetic methods. Database Structural data are available in the Protein Data Bank under the accession number(s) 3UAL [14-3-3ε/MLF1(29-42)pSer34 complex] and 3UBW [14-3-3ε/MLF1(29-42)pSer34/3-pyrrolidinol complex] Structured digital abstract ? 14-3-3 epsilon?and?MLF1?bind?by?x-ray crystallography?(View interaction) ? 14-3-3 epsilon?and?MLF1?bind?by?isothermal titration calorimetry?(View Interaction:?1,?2).  相似文献   

6.
Previous studies have shown that the deletion of brnQ from the Corynebacterium glutamicum chromosome results in a significant reduction in L-isoleucine uptake rates, while overexpression of brnFE leads to enhanced L-isoleucine export rates. Given that net excretion rates would be an important factor for high titers of L-isoleucine accumulation, we have tested the notion that decreased L-isoleucine uptake combined with increased L-isoleucine excretion will further improve high-yield strains that are currently used for the industrial-scale production of L-isoleucine. To examine the effect of the two carriers on L-isoleucine accumulation in L-isoleucine producer C. glutamicum YILW, we constructed a brnQ deletion mutant (C. glutamicum YILW?brnQ) and two brnFE overexpressors (C. glutamicum YILWpXMJ19brnFE and C. glutamicum YILW?brnQpXMJ19brnFE). Compared to the original strain, the efflux rate of the brnQ mutant increased from 19.0 to 23.6?nmol?min(-1) mg (dry wt)(-1) and its L-isoleucine titer increased from 154.3?mM (20.2?g?l(-1)) to 170.3?mM (22.3?g?l(-1)). The efflux rates of C. glutamicum YILWpXMJ19brnFE and C. glutamicum YILW?brnQpXMJ19brnFE were 33.5 and 39.1?nmol?min(-1) mg (dry wt)(-1), and their L-isoleucine production titers were 197.2?mM (25.9?g?l(-1)) and 221.0?mM (29.0?g?l(-1)), respectively. Our results suggest that modifications of the transport system could provide a promising avenue for further increasing L-isoleucine yield in the L-isoleucine producer.  相似文献   

7.
Pyruvate was produced from glucose by Escherichia coli BW25113 that contained formate dehydrogenase (FDH) from Mycobacterium vaccae. In aerobic shake-flask culture (K (L) a?=?4.9?min(-1)), the recombinant strain produced 6.7?g pyruvate?l(-1) after 24?h with 4?g sodium formate?l(-1) and a yield of 0.34?g pyruvate?g?glucose(-1). These values were higher than those of the original strain (0.2?g?l(-1) pyruvate and 0.02?g pyruvate?g?glucose(-1)). Based on the reaction mechanism of FDH, the introduction of FDH into E. coli enhances the accumulation of pyruvate by the regeneration of NADH from NAD(+) since NAD(+) is a shared cosubstrate with the pyruvate dehydrogenase complex, which decarboxylates pyruvate to acetyl-CoA and CO(2). The oxygenation level was enough high to inactivate lactate dehydrogenase, which was of benefit to pyruvate accumulation without lactate as a by-product.  相似文献   

8.
The aim of this study was to investigate the dynamic changes in plasma decorin concentration after acute ischemic stroke and to study its relationship with clinical stroke subtypes. We collected three plasma samples from patients with acute ischemic stroke (n?=?35) and controls (n?=?30): upon admission (1-3?days) between 3?days and 1?week (3-7?days), and between 7?days and 2?weeks (7-14?days). The relationship between Decorin concentration and Trial of ORG10172 in Acute Stroke Treatment (TOAST) subtypes and outcomes were evaluated. The concentration of decorin gradually decreased following the onset of stroke at all different time-points (<3?days, p?相似文献   

9.
Electroporation induced by high-strength electrical fields has long been used to investigate membrane properties and facilitate transmembrane delivery of molecules and genes for research and clinical purposes. In the heart, electric field-induced passage of ions through electropores is a factor in defibrillation and postshock dysfunction. Voltage-clamp pulses can also induce electroporation, as exemplified by findings in earlier studies on rabbit ventricular myocytes: Long hyperpolarizations to ≤-110?mV induced influx of marker ethidium and irregular inward currents that were as large with external NMDG(+) as Na(+). In the present study, guinea pig ventricular myocytes were bathed with NMDG(+), Na(+) or NMDG(+)?+?La(3+) solution (36°C) and treated with five channel blockers. Hyperpolarization of myocytes in NMDG(+) solution elicited an irregular inward current (I (ep)) that reversed at -21.5?±?1.5?mV. In myocytes hyperpolarized with 200-ms steps every 30?s, I (ep) occurred in "episodes" that lasted for one to four steps. Boltzmann fits to data on the incidence of I (ep) per experiment indicate 50% incidence at -129.7?±?1.4?mV (Na(+)) and -146.3?±?1.6?mV (NMDG(+)) (slopes ≈-7.5?mV). I (ep) amplitude increased with negative voltage and was larger with Na(+) than NMDG(+) (e.g., -2.83?±?0.34 vs. -1.40?±?0.22?nA at -190?mV). La(3+) (0.2?mM) shortened episodes, shifted 50% incidence by -35?mV and decreased amplitude, suggesting that it inhibits opening/promotes closing of electropores. We compare our findings with earlier ones, especially in regard to electropore selectivity. In the Appendix, relative permeabilities and modified excluded-area theory are used to derive estimates of electropore diameters consistent with reversal potential -21.5?mV.  相似文献   

10.
The adsorptions of hydrogen molecule of the Fe?-?doped pristine and Stone?-?Wales defected armchair (5,5) single?-?walled carbon nanotubes (SWCNTs) compared with the pristine SWCNT were investigated by using the density functional theory at the B3LYP/LanL2DZ level. The doping of Fe atom into SWCNTs occurring via an exothermic process was found. The adsorptions of hydrogen molecule on the Fe?-?doped structures of either perfect or SW defected SWCNTs are stronger than on their corresponding undoped structures. The structural and electronic properties of the pristine and SW defected SWCNTs, their Fe?-?doped structures and their hydrogen molecule adsorptions are reported.  相似文献   

11.
Bioavailable vanadium was evaluated on the basis of soil vanadium single-extraction with ethylenediaminetetraacetic acid (EDTA), hydrochloric acid (HCl), acetic acid (HOAc), and sodium nitrate (NaNO(3)) in Panzhihua urban park. The soil vanadium concentration extracted by HOAc was 0.01-2.07?mg?kg(-1), by EDTA 0.28-7.03?mg?kg(-1), by NaNO(3) 0.07-0.53?mg?kg(-1), and by HCl 0.19-1.36?mg?kg(-1). The bioavailable vanadium (bioavailable fraction) obtained with HOAc was 0.01-1.33%, with EDTA 0.27-4.09%, with NaNO(3) 0.13-0.72%, and with HCl 0.06-0.28%. In addition, the impact of soil properties, soil nutrients, and soil enzyme activities on bioavailability of vanadium is discussed in this study. Based on the characteristics of bioavailable vanadium in the soil, ecological and health risks should have been given more attention in the studied area.  相似文献   

12.
Исследовалось влияние рН и температуры на гидролитическое разложение гибберелевой кислоты в бу?ерных водных растворах. Отдельные продукты гидролиха определяли с помощью хроматогра?ии на бумаге при одновременной спектро?отометриче ской оцерке концентрации образующейся гиббереленовой кислоты. Было установлено, что разложение гибберелевой кислоты в кислой, нейтральной и щелочной среде начинается с образования 1-карбокси-2,3,7-тригидрок си-1-метил-8-метиленгиб б-4-ен 1–3лактон 10 карбоно войкислоты. Это вещес твоприсутствует так же в?ерментационных средах и на различных этапах выделения гибберелевой кислоты. Дальнейшее разложение в растворах с рН 2–8 проходит потом через гиббереленовую кислоту до аллогибберовой кислоты. Следующее превращение аллогибберовой кислоты в гибберовую наблюдалось только в растворе с рН 2 иосле 24-часового прогревания при при 100° С. В растворе с рН 9 процесс разложения приводие к образованию 2,3,7-тригидрокси-1-метил-8-м етиленгибб-4-ен 1,10 дикарбоновой кислоты, которая возникает как главный окончательный продукт гидролиза, наряду с небольшим количеством гиббереленовой кислоты, при данном рН также уже не подвергающейся дальнейшим изменениям. Наибольшей устойчивостью гиььерелевая кислота отличается в растворах с рН 3–4. В нейтральной, а в особенности в слабо щелочной среде ее устойчивость резко понижается. Разложение гибберелевой кислоты в водных растворах значительно ускозяется также при повышении температуры.  相似文献   

13.
Ecosystem nitrous oxide (N(2) O) emissions respond to changes in climate and CO(2) concentration as well as anthropogenic nitrogen (N) enhancements. Here, we aimed to quantify the responses of natural ecosystem N(2) O emissions to multiple environmental drivers using a process-based global vegetation model (DyN-LPJ). We checked that modelled annual N(2) O emissions from nonagricultural ecosystems could reproduce field measurements worldwide, and experimentally observed responses to step changes in environmental factors. We then simulated global N(2) O emissions throughout the 20th century and analysed the effects of environmental changes. The model reproduced well the global pattern of N(2) O emissions and the observed responses of N cycle components to changes in environmental factors. Simulated 20th century global decadal-average soil emissions were c. 8.2-9.5?Tg?N?yr(-1) (or 8.3-10.3?Tg?N?yr(-1) with N deposition). Warming and N deposition contributed 0.85?±?0.41 and 0.80?±?0.14?Tg?N?yr(-1) , respectively, to an overall upward trend. Rising CO(2) also contributed, in part, through a positive interaction with warming. The modelled temperature dependence of N(2) O emission (c. 1?Tg?N?yr(-1) K(-1) ) implies a positive climate feedback which, over the lifetime of N(2) O (114?yr), could become as important as the climate-carbon cycle feedback caused by soil CO(2) release.  相似文献   

14.
Hairy root cultures of Scutellaria lateriflora were established using Agrobacterium rhizogenes A4 and produced acteoside (18.5?mg?g(-1) dry wt), baicalin (14.5?mg?g(-1) dry wt) and wogonoside (12?mg?g(-1) dry wt). Yeast extract (50?μg?ml(-1)) increased acteoside production 1.4-fold and flavone production 1.7-fold after 7 and 14?days of elicitation. Addition of Pectobacterium carotovorum lysate in the stationary phase of the hairy root culture stimulated only the accumulation of wogonin to 30?mg?g(-1) dry wt. The production of wogonin in hairy roots could be associated with its role as a phytolaexin.  相似文献   

15.
Organic gold complexes have different biological activity, depending on their potential for interactions with key functional molecules.The aim of this study was to investigate potential of several newly synthesized organic gold complexes to influence spontaneous motility of the Fallopian tubes.The effects of [Au(bipy)Cl(2)](+) (dichloride(2,2'-bipyridyl)aurate(III)-ion), aurothiomalate, [Au(DMSO)(2)Cl(2)]Cl and DMSO on spontaneous motility of Fallopian tubes were tested on the isolated tube segments in vitro. Aurothiomalate (from 2.9?×?10(-9) to 4.9?×?10(-4)?M/l), [Au(bipy)Cl(2)]Cl (from 3.3?×?10(-9) to 4.2?×?10(-5)?M/l) and DMSO (from 1.9?×?10(-8) to 1.0?×?10(-5)?M/l) did not affect spontaneous contractions of the isolated Fallopian tube ampulla, while [Au(DMSO)(2)Cl(2)]Cl (from 2.9?×?10(-9) to 4.2?×?10(-5)?M/l) showed concentration-dependent increase (stimulation) of spontaneous contractions of the isolated Fallopian tube isthmus, and remained without effect on the isolated ampulla.The drugs designed as organic gold complexes with weaker bonds between the gold itself and organic part of a molecule could adversely affect motility of the Fallopian tubes, and theoretically fertility of women taking such drugs in their reproductive age.  相似文献   

16.
The diversity and density of methanogenic archaea and methane production were investigated ex situ at different growth stages of rice plant cultivated in compost-treated tropical rice fields. The qPCR analysis revealed variation in methanogens population from 3.40?×?10(6) to 1.11?×?10(7) copies?g(-1) dws, in the year 2009 and 4.37?×?10(6) to 1.36?×?10(7) copies?g(-1) dws in the year 2010. Apart from methanogens, a large number of bacterial (9.60?×?10(9) -1.44?×?10(10) copies?g(-1) dws) and archaeal (7.13?×?10(7) -3.02?×?10(8) copies?g(-1) dws) communities were also associated with methanogenesis. Methanogen population size varied in the order: flowering > ripening > tillering > postharvest > preplantation stage. The RFLP-based 16S rRNA gene-targeted phylogenetic analysis showed that clones were closely related to diverse group of methanogens comprising members of Methanomicrobiaceae, Methanosarcinaceae, Methanosaetaceae and RC I. Laboratory incubation studies revealed higher amount of cumulative CH(4) at the flowering stage. The integration of methanogenic community structure and CH(4) production potential of soil resulted in a better understanding of the dynamics of CH(4) production in organically treated rice-field soil. The hypothesis that the stages of plant development influence the methanogenic community structure leading to temporal variation in the CH(4) production has been successfully tested.  相似文献   

17.
Host genetic variation may affect the outcome of chronic viral hepatitides, favoring viral clearance and/or modulating the inflammatory response to persistent infection. Our aims were to assess whether interleukin 6 (IL-6) promoter polymorphisms are associated with chronic hepatitis C virus (HCV) infection and to clarify the role of IL-6 haplotypes in facilitating progressive disease. The study included 424 Italian patients (233 males, median age 53 years) affected by HCV chronic infection. IL6 -1363, -597, -572, -174, and +2954 polymorphic loci were assayed by means of restriction fragment length polymorphism. Three hundred forty-four healthy Italian blood donors (245 males, median age 50 years) served as controls. Comparing patients and controls analysis of molecular variance was highly significant (p?相似文献   

18.
Paper by Bogdan Jaroszewicz, Ewa Piro?nikow, Marcin Churski “Vegetation diversity influences endozoochoric seed dispersal by moose (Alces alces L.)“ in Voulme 8, Issue 12, 1250-1264/ December 2013; DOI: 10.2478/s11535-013-0244-3 contains incorrect affiliations of Ewa Piro?nikow and Marcin Churski. Ewa Pi?niow works in Institute of Biology, University of Bia?ystok, 15-950 Bia?ystok, Poland; while Marcin Churski works in Mammal Research Institute, Polish Academy of Sciences, 17–230 Bia?owie?a, Poland.  相似文献   

19.
An 8-week feeding trial was conducted to investigate the effects of dietary mannan oligosaccharide (MOS) on growth performance, gut morphology, and NH(3) stress tolerance of Pacific white shrimp Litopenaeus vannamei. Juvenile Pacific white shrimp (1080 individuals with initial weight of 2.52?±?0.01?g) were fed either control diet without MOS or one of five dietary MOS (1.0, 2.0, 4.0, 6.0 and 8.0?g?kg(-1)) diets. After the 8-week feeding trial, growth parameters, immune parameters, intestinal microvilli length and resistance against NH(3) stress were assessed. Weight gain (WG) and specific growth rate (SGR) were significantly higher (P??0.05) in all experimental groups. Compared with control group, TEM analysis revealed that 2.0, 4.0, 6.0 and 8.0?g?kg(-1) MOS supplementation could significantly increase (P?相似文献   

20.
棕色田鼠的发声及其频谱分析   总被引:4,自引:1,他引:3  
对不同年龄的棕色田鼠在不同状态下的发声进行了声谱分析,以研究其发声与行为之间的关系及其发育规律。棕色田鼠幼体的频谱图较简单,一般有1-2个波峰,主能峰频率在1800HZ左右,且能量区为1个,位于中频区(1300-2500HZ);发声以单音节为主,持续40-100μs。亚成体频谱图较幼体复杂,为2个相近的能量区,均位于中频区(750-1320Hz,1431-1570Hz),MPF=945Hz;叫声单  相似文献   

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