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31.
Chemical composition of cell walls of Saccharomyces fragilis 总被引:1,自引:0,他引:1
T Reuvers E Tacoronte C G Mendoza M Novaes-Ledieu 《Canadian journal of microbiology》1969,15(9):989-993
32.
Damian Niegowski Thea Kleinschmidt Shabbir Ahmad Abdul Aziz Qureshi Michaela M?rback Agnes Rinaldo-Matthis Jesper Z. Haeggstr?m 《PloS one》2014,9(5)
Leukotriene (LT) C4 synthase (LTC4S) is an integral membrane protein that catalyzes the conjugation reaction between the fatty acid LTA4 and GSH to form the pro-inflammatory LTC4, an important mediator of asthma. Mouse models of inflammatory disorders such as asthma are key to improve our understanding of pathogenesis and potential therapeutic targets. Here, we solved the crystal structure of mouse LTC4S in complex with GSH and a product analog, S-hexyl-GSH. Furthermore, we synthesized a nM inhibitor and compared its efficiency and binding mode against the purified mouse and human isoenzymes, along with the enzymes’ steady-state kinetics. Although structural differences near the active site and along the C-terminal α-helix V suggest that the mouse and human LTC4S may function differently in vivo, our data indicate that mouse LTC4S will be a useful tool in future pharmacological research and drug development. 相似文献
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Genetically modified (GM) cotton altered for insect and herbicide resistance released into commercial production in 1996 to 1997 now accounts for the lion's share of cotton acreage in the U.S. The rapid increase in transgenic cotton acreage in such a short period of time attests to the overall success of agricultural biotechnology. Grower satisfaction with transgenic cotton is largely due to several significant benefits, such as lower production costs, streamlined yet flexible management, and a reduced impact on the environment. This review article provides an overview of what has been accomplished thus far, as well as what improved germplasm may lurk on the horizon. A critical assessment of the gene delivery systems in cotton and possible targets for improvement is presented. The performance of the first generation of transgenic cotton plants engineered for insect, disease, or herbicide resistance is evaluated from the perspective of the benefits, the limitations that impact field performance, and management strategies. A few traits that hold future promise for increasing fiber productivity, enhancing and/or increasing the novelty of cotton-based products for the consumer, and improving human health and well-being are presented. Above all, cotton biotechnology offers to greatly enhance breeding programs by introducing novel traits that have eluded more traditional plant improvement methods and therefore will likely play an increasingly important role in the genetic improvement of cotton. 相似文献
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BACKGROUND: In contrast to most populations worldwide, the incidence of gastric cancer increases among Inuit in Greenland. Contributing factors to this increase are unknown, but Helicobacter pylori may be involved. However, little is known regarding the epidemiology of H. pylori in Arctic communities. With the aim of determining age-specific prevalence, risk factors, and association with clinical conditions of H. pylori infection, we carried out a population-based study of H. pylori in Sisimiut, the second biggest town of Greenland. MATERIALS AND METHODS: A population-based sample of 685 persons had serum drawn that was analyzed for H. pylori IgG antibodies using enzyme-linked immunosorbent assay (ELISA). Risk factors analyses were carried out using multivariate logistic regression models. RESULTS: The seroprevalence was lowest among children aged 0-4 years (6%), but increased rapidly thereafter. In persons aged 15-87 years the seroprevalence had stabilized around 58%. Total number of children in household, number of older, but not younger, siblings and narrow age gap to closest older sibling were associated with H. pylori seropositivity. In contrast, number of adults in household and socioeconomic status did not influence serostatus. CONCLUSIONS: The age-specific prevalence pattern in Greenland is intermediate between that of developing and developed countries. The risk factor pattern indicates crowding and older siblings in particular to be key elements in risk of infection. 相似文献
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Thea Ø. Bechshøft Christian Sonne Frank F. Rigét Øystein Wiig Rune Dietz 《Polar Biology》2008,31(8):945-958
Size, growth and sexual dimorphism of nine skull traits was studied in 300 East Greenland and 391 Svalbard polar bears (Ursus maritimus). Two traits were significantly larger in bears from East Greenland compared to Svalbard bears, and trait size was smaller
after 1960 in five traits. For both localities and both age groups (subadult, adult), mean trait size values were higher in
males than females (all: P < 0.05). Gompertz growth models showed trait size increasing with age in seven traits. Depending on the trait, males reached
95% asymptotic trait size at age 3–10, females at age 2–6. The females of both localities matured at approximately the same
age, whereas the Svalbard males generally matured years later than their East Greenland peers. The differences found in the
present study between the two polar bear subpopulations support the notion that East Greenland and Svalbard polar bears probably
should be managed as separate units. 相似文献
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Laura Heath Susan Conway Laura Jones Katherine Semrau Kyle Nakamura Jan Walter W. Don Decker Jason Hong Thomas Chen Marintha Heil Moses Sinkala Chipepo Kankasa Donald M. Thea Louise Kuhn James I. Mullins Grace M. Aldrovandi 《PloS one》2010,5(4)