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951.
The human myoglobin gene: a third dispersed globin locus in the human genome. 总被引:2,自引:0,他引:2 下载免费PDF全文
A J Jeffreys V Wilson A Blanchetot P Weller A Geurts van Kessel N Spurr E Solomon P Goodfellow 《Nucleic acids research》1984,12(7):3235-3243
Human myoglobin is specified by a single gene. Unique sequence DNA probes were isolated from the cloned gene and used to test for the presence of the human myoglobin gene in a series of human rodent somatic cell hybrids containing various complements of human chromosomes. The myoglobin gene cosegregated with human chromosome 22. Somatic cell hybrids containing translocation chromosomes carrying part of chromosome 22 were used to locate the myoglobin gene to the region 22q11----22q13. The myoglobin gene is therefore not linked to the alpha-globin gene cluster on chromosome 16 or the beta-globin cluster on chromosome 11, and represents a third dispersed globin locus in the human genome. 相似文献
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Chris van Kessel Rodney Venterea Johan Six Maria Arlene Adviento‐Borbe Bruce Linquist Kees Jan van Groenigen 《Global Change Biology》2013,19(1):33-44
No‐tillage and reduced tillage (NT/RT) management practices are being promoted in agroecosystems to reduce erosion, sequester additional soil C and reduce production costs. The impact of NT/RT on N2O emissions, however, has been variable with both increases and decreases in emissions reported. Herein, we quantitatively synthesize studies on the short‐ and long‐term impact of NT/RT on N2O emissions in humid and dry climatic zones with emissions expressed on both an area‐ and crop yield‐scaled basis. A meta‐analysis was conducted on 239 direct comparisons between conventional tillage (CT) and NT/RT. In contrast to earlier studies, averaged across all comparisons, NT/RT did not alter N2O emissions compared with CT. However, NT/RT significantly reduced N2O emissions in experiments >10 years, especially in dry climates. No significant correlation was found between soil texture and the effect of NT/RT on N2O emissions. When fertilizer‐N was placed at ≥5 cm depth, NT/RT significantly reduced area‐scaled N2O emissions, in particular under humid climatic conditions. Compared to CT under dry climatic conditions, yield‐scaled N2O increased significantly (57%) when NT/RT was implemented <10 years, but decreased significantly (27%) after ≥10 years of NT/RT. There was a significant decrease in yield‐scaled N2O emissions in humid climates when fertilizer‐N was placed at ≥5 cm depth. Therefore, in humid climates, deep placement of fertilizer‐N is recommended when implementing NT/RT. In addition, NT/RT practices need to be sustained for a prolonged time, particularly in dry climates, to become an effective mitigation strategy for reducing N2O emissions. 相似文献
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Tone F. Bathen Brigitte Geurts Beathe Sitter Hans E. Fj?sne Steinar Lundgren Lutgarde M. Buydens Ingrid S. Gribbestad Geert Postma Guro F. Giske?deg?rd 《PloS one》2013,8(4)
In this study, the feasibility of high resolution magic angle spinning (HR MAS) magnetic resonance spectroscopy (MRS) of small tissue biopsies to distinguish between tumor and non-involved adjacent tissue was investigated. With the current methods, delineation of the tumor borders during breast cancer surgery is a challenging task for the surgeon, and a significant number of re-surgeries occur. We analyzed 328 tissue samples from 228 breast cancer patients using HR MAS MRS. Partial least squares discriminant analysis (PLS-DA) was applied to discriminate between tumor and non-involved adjacent tissue. Using proper double cross validation, high sensitivity and specificity of 91% and 93%, respectively was achieved. Analysis of the loading profiles from both principal component analysis (PCA) and PLS-DA showed the choline-containing metabolites as main biomarkers for tumor content, with phosphocholine being especially high in tumor tissue. Other indicative metabolites include glycine, taurine and glucose. We conclude that metabolic profiling by HR MAS MRS may be a potential method for on-line analysis of resection margins during breast cancer surgery to reduce the number of re-surgeries and risk of local recurrence. 相似文献
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Over the past decade, immunohistochemical studies have provided compelling evidence that gray matter (GM) pathology in multiple sclerosis (MS) is extensive. Until recently, this GM pathology was difficult to visualize using standard magnetic resonance imaging (MRI) techniques. However, with newly developed MRI sequences, it has become clear that GM damage is present from the earliest stages of the disease and accrues with disease progression. GM pathology is clinically relevant, as GM lesions and/or GM atrophy were shown to be associated with MS motor deficits and cognitive impairment. Recent autopsy studies demonstrated significant GM demyelination and microglia activation. However, extensive immune cell influx, complement activation and blood-brain barrier leakage, like in WM pathology, are far less prominent in the GM. Hence, so far, the cause of GM damage in MS remains unknown, although several plausible underlying pathogenic mechanisms have been proposed. This paper provides an overview of GM damage in MS with a focus on its topology and histopathology. 相似文献
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The colonial sheath of Microcystis marginata has a definite structure as seen by light and electron microscopy, consisting of a relatively smooth inner surface and densely packed, long fibrils on the outer surface. The sheath initially forms around the single cell and expands by continual deposition of sheath material to accomodate the synchronously dividing cells of the colony. 相似文献
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Effects of camptothecin on RNA synthesis in L-1210 cells 总被引:1,自引:0,他引:1