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排序方式: 共有664条查询结果,搜索用时 15 毫秒
1.
Suzanne Camus Sergio Menéndez Kenneth Fernandes Nelly Kua Geng Liu Dimitris P. Xirodimas David P. Lane Jean-Christophe Bourdon 《Cell cycle (Georgetown, Tex.)》2012,11(8):1646-1655
The discovery that the single p53 gene encodes several different p53 protein isoforms has initiated a flurry of research into the function and regulation of these novel p53 proteins. Full-length p53 protein level is primarily regulated by the E3-ligase Mdm2, which promotes p53 ubiquitination and degradation. Here, we report that all of the novel p53 isoforms are ubiquitinated and degraded to varying degrees in an Mdm2-dependent and -independent manner, and that high-risk human papillomavirus can degrade some but not all of the novel isoforms, demonstrating that full-length p53 and the p53 isoforms are differentially regulated. In addition, we provide the first evidence that Mdm2 promotes the NEDDylation of p53β. Altogether, our data indicates that Mdm2 can distinguish between the p53 isoforms and modify them differently. 相似文献
2.
Six bisindole alkaloids have been isolated from the leaves of Dyera costulata (Apocynaceae). One is the known ochrolifuanine A and the others are the novel ochrolifuanines E and F, and the 18-dehydroochrolifuanines A, E and F. 相似文献
3.
Valeriy A. Sterligov Iaroslav O. Grytsaienko Yakiv Men Maxim L. Nesterov Alexey Yu. Nikitin 《Plasmonics (Norwell, Mass.)》2014,9(2):219-226
The enhancement factor for surface plasmon–polaritons scattering by a thin dielectric grating was measured experimentally. Scattering of a p-polarized wave may be up to 30,000 times stronger than the non-resonant scattering of an s-polarized wave by the same grating. A detailed comparison between the theoretical calculations and experimental measurements was performed. Strong localization of the scattered field near the edges of diffraction grating grooves was found. Such localization is very promising for numerous applications, e.g., biological sensors, optical tweezers for catching particles, or viruses, etc. 相似文献
4.
O Domínguez-López A Fernández-Riestra B Marín A Menéndez-Patterson 《Revista Espanola de Fisiología》1985,41(2):151-159
The effects of interaction of the thyroid function with the submaxillary glands on the female rat, on the body growth, weight evolution of adrenal glands, ovary and parotid glands, puberty onset, estrous cycle, fertility, gestation and offspring size, plasmatic levels of glucose, glucagon, Na+, K+ and total protein have been studied. The effects of sialadenectomy and thyroid function are both independent in all parameters, except in ovary growth, which is depressed by thyroid function when submaxillary glands are removed, and in circulating glucose, since sialadenectomy stabilizes to hypoglycemia which results from thyroidectomy. 相似文献
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Jiangang Yang Chaoyu Tian Tong Zhang Chenxi Ren Yueming Zhu Yan Zeng Yan Men Yuanxia Sun Yanhe Ma 《Biotechnology and bioengineering》2019,116(4):745-756
D -Allulose 3-epimerase (DAE) has been applied to produce D -allulose, a low-calorie and functional sweetener. In this study, a new DAE from Paenibacillus senegalensis was characterized in Escherichia coli. Furthermore, we presented a tandem isoenzyme gene expression strategy to express multiple DAEs in one cell and construct food-grade expression systems based on Corynebacterium glutamicum. Seventeen expression cassettes based on three DAE genes from different organisms were constructed. Among all recombinant strains, DAE16 harboring three DAE genes in an expression vector exhibited the highest enzyme activity with 22.7 U/mg. Whole-cell transformation of DAE16 produced 225 g/L D -allulose with a volumetric productivity of 353 g·g −1·hr −1. The catalytic efficiency of strain C-DAE9 integrating total 11 DAE genes in chromosome was 16.4-fold higher than strains carrying one DAE. Fed-batch culture of C-DAE9 gave enzyme activity of 44,700 U/L. We also expressed a thermostable invertase in C. glutamicum and obtained enzyme activity of 29 U/mg. Immobilized cells expressing DAE or invertase exhibited 80% of retained activity after 30 cycles of catalytic reactions. Those immobilized cells were coupled to produce 61.2 g/L D -allulose from cane molasses in a two-step reaction process. This study provided an efficient approach for enzyme preparation and allowed access to produce D -allulose from other abundant and low-cost feedstock enriched with sucrose. 相似文献
9.
Manfred Accrombessi Sma?la Ouédraogo Gino Cédric Agbota Raquel Gonzalez Achille Massougbodji Clara Menéndez Michel Cot 《PloS one》2015,10(6)
Background
Anaemia is an increasingly recognized health problem in Africa, particularly in infants and pregnant women. Although malaria is known to be the main risk factor of anaemia in both groups, the consequences of maternal factors, particularly malaria in pregnancy (MiP), on infant haemoglobin (Hb) concentrations during the first months of life are still unclear.Methods
We followed-up a cohort of 1005 Beninese pregnant women from the beginning of pregnancy until delivery. A subsample composed of the first 400 offspring of these women were selected at birth and followed until the first year of life. Placental histology and blood smear at 1st clinical antenatal visit (ANC), 2nd ANC and delivery were used to assess malaria during pregnancy. Infant Hb concentrations were measured at birth, 6, 9 and 12 months of age. A mixed multi-level model was used to assess the association between MiP and infant Hb variations during the first 12 months of life.Results
Placental malaria (difference mean [dm] = - 2.8 g/L, 95% CI [-5.3, -0.3], P = 0.03) and maternal peripheral parasitaemia at delivery (dm = - 4.6 g/L, 95% CI [-7.9, -1.3], P = 0.007) were the main maternal factors significantly associated with infant Hb concentrations during the first year of life. Poor maternal nutritional status and malaria infection during infancy were also significantly associated with a decrease in infant Hb.Conclusion
Antimalarial control and nutritional interventions before and during pregnancy should be reinforced to reduce specifically the incidence of infant anaemia, particularly in Sub-Saharan countries. 相似文献10.
Tracing dietary origins of aphids and the predatory beetle Propylea japonica in agricultural systems using stable isotope analyses 下载免费PDF全文
Xianghui Liu Xingyuan Men Yongsheng Zhang Zihua Zhao Feng Ge 《Entomologia Experimentalis et Applicata》2015,155(2):87-94
Tracing dietary origins of the predatory beetle Propylea japonica (Thunberg) (Coleoptera: Coccinellidae) aids understanding their roles in the food web and provides information to develop strategies for effective conservation in agroecosystems comprised of wheat [Triticum aestivum L. (Poaceae)], cotton [Hirsutum spp. (Malvaceae)], and maize [Zea mays L. (Poaceae)]. Intrinsic markers of carbon and nitrogen stable isotope ratios (δ13C and δ15N) in P. japonica need to be developed to ascertain the source(s) of diet. Experiments were carried out to examine the changes of δ13C and δ15N among the three crops, pests (wheat, cotton, and maize aphids; all Hemiptera: Aphididae), and P. japonica fed on aphids of each of the three crops. Results indicated that δ13C values in P. japonica fed on wheat, cotton, and maize aphids were ?27.2 to ?26.5‰, ?24.2 to ?23.9‰, and ?11.0 to ?10.7‰, respectively, whereas their δ15N values were 1.1 to 2.9‰, 6.0 to 7.4‰, and ?0.6 to 0.1‰, respectively. δ13C and δ15N plots clearly identify the three crops, the dietary origins of the aphids, and the host origins of the aphid prey consumed by the ladybird beetles, as each pathway displays a non‐overlapping pattern. Based on the values of δ13C and δ15N of the three food webs, dietary origins can be traced in the predatory beetle P. japonica derived from wheat, cotton, and maize crops. 相似文献