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DNA restriction fragment analysis of the proopiomelanocortin gene in schizophrenia and bipolar disorders. 总被引:2,自引:1,他引:1 下载免费PDF全文
J Feder H M Gurling J Darby L L Cavalli-Sforza 《American journal of human genetics》1985,37(2):286-294
The method of DNA restriction fragment analysis using gene probes for the proopiomelanocortin (POMC) gene was employed to detect possible molecular variation in the POMC gene in schizophrenia and bipolar illness. No gross structural abnormalities in restriction fragments were observed with the set of restriction enzymes used. Two allelic restriction sites were observed giving rise to fragment length polymorphisms. One of these is a new polymorphism, not previously reported, which will be of value as a linkage marker. The associations between the two DNA polymorphisms that are closely linked to the POMC gene and both schizophrenia and bipolar disorder were investigated. No association was found, thus adding weight to the evidence that there are no alterations in the POMC gene in schizophrenia and bipolar illness. 相似文献
43.
Extraction of RNA from mammalian tissue culture cells 总被引:1,自引:0,他引:1
A rapid method is described for the effective fractionation and extraction of undergraded nuclear and cytoplasmic RNA species from mammalian tissue culture cells. It is compared in detail with several existing procedures. 相似文献
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Matthias Albrecht David Kleijn Neal M. Williams Matthias Tschumi Brett R. Blaauw Riccardo Bommarco Alistair J. Campbell Matteo Dainese Francis A. Drummond Martin H. Entling Dominik Ganser G. Arjen de Groot Dave Goulson Heather Grab Hannah Hamilton Felix Herzog Rufus Isaacs Katja Jacot Philippe Jeanneret Mattias Jonsson Eva Knop Claire Kremen Douglas A. Landis Gregory M. Loeb Lorenzo Marini Megan McKerchar Lora Morandin Sonja C. Pfister Simon G. Potts Maj Rundlf Hillary Sardias Amber Sciligo Carsten Thies Teja Tscharntke Eric Venturini Eve Veromann Ines M.G. Vollhardt Felix Wckers Kimiora Ward Andrew Wilby Megan Woltz Steve Wratten Louis Sutter 《Ecology letters》2020,23(10):1488-1498
Floral plantings are promoted to foster ecological intensification of agriculture through provisioning of ecosystem services. However, a comprehensive assessment of the effectiveness of different floral plantings, their characteristics and consequences for crop yield is lacking. Here we quantified the impacts of flower strips and hedgerows on pest control (18 studies) and pollination services (17 studies) in adjacent crops in North America, Europe and New Zealand. Flower strips, but not hedgerows, enhanced pest control services in adjacent fields by 16% on average. However, effects on crop pollination and yield were more variable. Our synthesis identifies several important drivers of variability in effectiveness of plantings: pollination services declined exponentially with distance from plantings, and perennial and older flower strips with higher flowering plant diversity enhanced pollination more effectively. These findings provide promising pathways to optimise floral plantings to more effectively contribute to ecosystem service delivery and ecological intensification of agriculture in the future. 相似文献
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Anne Lorrain Heidi Pethybridge Nicolas Cassar Aurore Receveur Valrie Allain Nathalie Bodin Laurent Bopp C. Anela Choy Leanne Duffy Brian Fry Nicolas Goi Brittany S. Graham Alistair J. Hobday John M. Logan Frederic Mnard Christophe E. Menkes Robert J. Olson Dan E. Pagendam David Point Andrew T. Revill Christopher J. Somes Jock W. Young 《Global Change Biology》2020,26(2):458-470
Considerable uncertainty remains over how increasing atmospheric CO2 and anthropogenic climate changes are affecting open‐ocean marine ecosystems from phytoplankton to top predators. Biological time series data are thus urgently needed for the world's oceans. Here, we use the carbon stable isotope composition of tuna to provide a first insight into the existence of global trends in complex ecosystem dynamics and changes in the oceanic carbon cycle. From 2000 to 2015, considerable declines in δ13C values of 0.8‰–2.5‰ were observed across three tuna species sampled globally, with more substantial changes in the Pacific Ocean compared to the Atlantic and Indian Oceans. Tuna recorded not only the Suess effect, that is, fossil fuel‐derived and isotopically light carbon being incorporated into marine ecosystems, but also recorded profound changes at the base of marine food webs. We suggest a global shift in phytoplankton community structure, for example, a reduction in 13C‐rich phytoplankton such as diatoms, and/or a change in phytoplankton physiology during this period, although this does not rule out other concomitant changes at higher levels in the food webs. Our study establishes tuna δ13C values as a candidate essential ocean variable to assess complex ecosystem responses to climate change at regional to global scales and over decadal timescales. Finally, this time series will be invaluable in calibrating and validating global earth system models to project changes in marine biota. 相似文献
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Cesar B. Ramírez-López Rita Beltrán-Sánchez Alistair Hernández-Izquierdo José Luis SalvadorHernández Eduardo Salcedo-Pérez Rosa E. del Río Mauro M. Martínez Pacheco 《Phyton》2021,90(3):907-920
This study scrutinized the possibility of finding toxicant or deterrent plant metabolites against the dry wood termite Incisitermes marginipennis (Latreille). Plant deterrent agents act as repellents or antifeedants to prevent
wood decay and increase its useful life. The potential of the tree Caesalpinia coriaria (Fabaceae) as a biological
source of molecules with deterrent effects against the dry wood termite was assessed by a phytochemical fractionation guided by repellence and antifeedant activities. The gas chromatography-mass spectrometry analysis of the
leaf essential oil showed geraniol to be one of the major components and its repellent and antifeedant effects were
determined. Geraniol had only an antifeedant effect without affecting the body weight or survival of the dry wood
termite. Unlike the leaf essential oil, geraniol did not exhibit a repellency effect. An in-silico approach of the activity of acetylcholinesterase in interaction with geraniol resulted in an affinity energy of −7.5 Kcal/mol. Geraniol
interacted with the amino acid tyrosine 324 located in the enzyme’s active site while citronellol (negative control)
interacted with tryptophan 83 located adjacent to the active site. These deterring terpenes have not been implemented for the preservation and restoration of wood products exposed to the attack of the dry wood termite.
However, they are an important natural control alternative. 相似文献
48.
Environmental Biology of Fishes - Shorthead sculpin (Cottus confusus Bailey and Bond, 1963) in Birch Creek, Idaho, were infected with the trematode Euryhelmis cotti (Simon, 1972). Our objective was... 相似文献
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Nuria Mencia-Trinchant Matthew J. MacKay Christopher Chin Ebrahim Afshinnekoo Jonathan Foox Cem Meydan Daniel Butler Christopher Mozsary Nicholas A. Vernice Charlotte Darby Michael C. Schatz Susan M. Bailey Ari M. Melnick Monica L. Guzman Kelly Bolton Lior Z. Braunstein Francine Garrett-Bakelman Ross L. Levine Christopher E. Mason 《Cell reports》2021,34(6):108740