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81.
82.
Jannett Nguyen Tiffany Alexander Hong Jiang Natasha Hill Zied Abdullaev Svetlana D. Pack Amy P. Hsu Steven M. Holland Dennis D. Hickstein Eric A. Engels Isaac Brownell 《Pigment cell & melanoma research》2018,31(2):337-340
GATA2 deficiency is a recently described genetic disorder affecting hematopoietic stem cells and is associated with immunodeficiency, hematologic malignancy, and various cutaneous pathologies including cutaneous tumors. To explore the incidence and clinical course of melanoma in patients with germline GATA2 deficiencies, we conducted a retrospective chart review of 71 such patients and identified two with invasive melanoma. One melanoma was diagnosed early because it was associated with pruritus due to a graft‐versus‐tumor effect following bone marrow transplantation. The other one, a lentigo maligna melanoma, was locally excised but progressed to widespread metastasis and death several years later. Our observations and published studies of melanoma biology suggest an association between decreased GATA2 expression and melanoma progression. These findings suggest that GATA2 deficient patients may have an increased risk of melanoma and should be observed closely for new or changing skin lesions. 相似文献
83.
The effects of suboptimal root zone temperatures (RZTs) on net translocation rates from the roots to the shoots and the concentrations
of Fe, Mn, Zn, and Cu were examined in maize grown in nutrient solution or soil. Plants were grown at 12 °C, 18 °C and 24
°C RZT. At each RZT, the growth-related shoot demand for nutrients was varied by independently modifying the temperature of
the shoot base (SBT) including the apical shoot meristem.
The net translocation rates of Mn and Zn from the roots to the shoots were reduced at low RZTs, irrespective of the SBT and
of the substrate (soil or nutrient solution). Obviously, the net translocation rates of Mn and Zn at low RZT were mainly regulated
by temperature effects on the roots and not by the chemical nutrient availability in the rhizosphere or by shoot growth rate
as controlled by SBTs. When both RZT and SBT were reduced, the decrease in net translocation rates of Mn and Zn was similar
to the decline in the shoot growth rate and concentrations of Mn and Zn in the shoot fresh matter were not greatly affected
or were even increased by low RZT. However, at high SBT and low RZT in nutrient solution, the depressed net translocation
rates of Mn and Zn combined with the increased shoot growth resulted in significantly decreased concentrations of Mn and Zn
in the shoot, indicating that Mn and Zn may become deficient even at high chemical availability.
By contrast to Mn and Zn, the net translocation rates of Fe and Cu at all RZTs were markedly enhanced by increased SBTs. Accordingly,
the concentrations of Fe and Cu in the shoot fresh matter were not greatly affected by RZTs, irrespective of the SBTs. These
results indicate that the ability of roots to supply Fe and Cu to the shoot was internally regulated by the growth related
shoot demand per unit of roots.
Deceased 21 September 1996
Deceased 21 September 1996 相似文献
84.
Test plantings with varieties ofLolium multiflorum andL perenne were harvested 4 to 7 times a year in 1991 and 1992. Samples were checked for the presence ofFusaria, the mycotoxins zearalenone, T-2 toxin, and diacetoxyscirpenol (DAS). Spectrum of species and the incidence ofFusaria and fusariotoxins are discussed in relation to the influencing factors site, variety ofLolium, harvesting time and year. Depending on these factors, 41 % to 100 % of the samples wereFusarium positive. Differences in infestation with Fusarium among varieties ofLolium perenne were dependent on location and did not correlate with yield. The six species ofFusarium pathogenic toLolium spp. (F. graminearum, F. culmorum, F. avenaceum, F. oxysporum, F. solani, and F. acuminatum) totaled 35.7 % of all the isolated strains. 14 species could be isolated fromLolium samples (descending frequency):F. culmorum, F. sambucinum, F. equiseti, F. acuminatum, F. semitectum, F. oxysporum, F. subglutinans, F. avenaceum, F. sporotrichioides, F. proliferatum, F. tricinctum, F. anthophilum, F. dimerum and F. graminearum. For the detection ofFusaria a promising new immunological method is presented. It is based on the genus specific production of exopolysaccharides byFusarium species. Mycotoxin contents in grass ranged from 0.01 to 4.75 ppm for zearalenone with 67 % positive samples and 0.3 % samples above 1 ppm, 0.04 to 2.78 ppm for T-2 toxin with 25 % positive samples and 2.8 % samples above 1 ppm, and 0.003 to 0.06 for DAS with 21.6 % positive samples. In silages, no T-2 toxin was detectable. IsolatedFusarium strains were checked for the ability to produce the mycotoxins zearalenone, T-2 toxin and DAS in culture. Most of the strains were positive for at least one of the toxins. 相似文献
85.
Axel H. Meyer Karin Schmuck Corinne Morel William Wishart Hermann Lübbert Peter Engels 《Genomics》1996,38(3):435
Phospholipases A2 (PLA2) form an extended class of enzymes that play an important role in signal transduction. Phospholipase A2-like (PLA2L) belongs to the secreted forms of phospholipases A2, but constitutes a new subgroup. We have assigned the gene for this enzyme to human chromosome 8q24–qter using fluorescencein situhybridization and radiation hybrid mapping techniques. 相似文献
86.
Matthias Mag Jochen Muth Kerstin Jahn Anusch Peyman Gerhard Kretzschmar Joachim W. Engels Eugen Uhlmann 《Bioorganic & medicinal chemistry》1997,5(12):2213-2220
A method for the synthesis of chimeric oligodeoxynucleotides comprised of phosphodiester and phenylphosphonate [3′-O-P(=O)(C6H5)-O-5′] or phenylphosphono-thioate [3′-O-P(=S)(C6H5)-O-5′] linkages has been developed. Synthesis was performed using suitably protected nucleoside phenylphosphonamidites as building blocks following an adjusted solid-phase phosphoramidite synthesis protocol. The new oligodeoxy-nucleotide analogues were characterized by electrospray ionization- and matrix-assisted laser desorption mass spectrometry, as well as by 31P NMR spectroscopy. Additionally, their binding properties to complementary oligodeoxynucleotides has been studied. 相似文献
87.
88.
Raúl F Pérez-Tasigchana Luz M. León-Mu?oz Esther López-García José R. Banegas Fernando Rodríguez-Artalejo Pilar Guallar-Castillón 《PloS one》2016,11(3)
Introduction
In older adults, the Mediterranean diet is associated with lower risk of chronic diseases, but its association with health-related quality of life (HRQL) is still uncertain. This study assessed the association between the Mediterranean diet and HRQL in 2 prospective cohorts of individuals aged ≥60 years in Spain.Methods
The UAM-cohort (n = 2376) was selected in 2000/2001 and followed-up through 2003. At baseline, diet was collected with a food frequency questionnaire, which was used to develop an 8-item index of Mediterranean diet (UAM-MDP). The Seniors-ENRICA cohort (n = 1911) was recruited in 2008/2010 and followed-up through 2012. At baseline, a diet history was used to obtain food consumption. Mediterranean diet adherence was measured with the PREDIMED score and the Trichopoulou’s Mediterranean Diet Score (MSD). HRQL was assessed, at baseline and at the end of follow-up, with the physical and mental component summaries (PCS and MCS) of the SF-36 questionnaire in the UAM-cohort, and the SF-12v.2 questionnaire in the Seniors-ENRICA cohort. Analyses were conducted with linear regression, and adjusted for the main confounders including baseline HRQL.Results
In the UAM-cohort, no significant associations between the UAM-MDP and the PCS or the MCS were found. In the Seniors-ENRICA cohort, a higher PREDIMED score was associated with a slightly better PCS; when compared with the lowest tertile of PREDIMED score, the beta coefficient (95% confidence interval) for PCS was 0.55 (-0.48 to 1.59) in the second tertile, and 1.34 (0.21 to 2.47) in the highest tertile. However, the PREDIMED score was non-significantly associated with a better MCS score. The MSD did not show an association with either the PCS or the MCS.Conclusions
No clinically relevant association was found between the Mediterranean diet and HRQL in older adults in Spain. 相似文献89.
Synthesis and selective cleavage of oligodeoxyribonucleotides containing non-chiral internucleotide phosphoramidate linkages. 总被引:3,自引:3,他引:0
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Oligodeoxynucleotides containing phosphoramidate internucleotide links 3'-OP(O)NH-5' have been prepared using standard solid phase phosphoramidite techniques. For the incorporation of the phosphoramidate linkages we have used monomer as well as dimer building blocks. With the monomer 3'-phosphoramidite building blocks, which are derived from 5'-amino-2',5'-dideoxynucleosides, it is possible to incorporate phosphoramidate links into specific positions within an oligodeoxynucleotide. Furthermore the synthesis of several dinucleoside phosphate derivatives which are linked by phosphoramidate bonds are described. The internucleotide phosphoramidate linkage was performed using the Staudinger reaction followed by a Michaelis-Arbuzov type transformation. After 3'-phosphitylation these dinucleosides are compatible with the current phosphoramidite methodology of oligodeoxynucleotide synthesis. 相似文献
90.
Extraoocytäre Komponenten des Eiwachstums beiApis Mellifica 总被引:1,自引:0,他引:1
Wolf Engels 《Insectes Sociaux》1968,15(3):271-288