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Highlights? PGC-1 induces pigment formation in melanocytes ? PGC-1s activate expression of MITF ? α-MSH induces PGC-1s, which are required for induction of melanogenic genes ? eQTLs in human PGC-1β are associated with tanning ability and melanoma protection  相似文献   
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Introduction  

We evaluated the three-year impact of adalimumab on patient-reported physical function and health-related quality-of-life (HRQOL) outcomes in patients with active ankylosing spondylitis (AS).  相似文献   
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Acclimation of light sensitivity of hydraulic conductance of shoots of silver birch (Betula pendula) and hybrid aspen (Populus × wettsteinii) to growth environments with three different air humidities was studied. Hydraulic conductance of shoots kept for 1–2 h in darkness (D) or in light (L) was measured by the pressure chamber method, and light sensitivity was defined as a significant difference between D and L shoots. Light sensitivity of shoots grown in three different air humidities was found to vary. Amongst shoots grown in current natural air, only the hydraulic conductance of the whole shoot and that of the leaf blades of birch upper foliage were significantly light sensitive. Amongst shoots grown in decreased air humidity, hydraulic conductance of the whole shoot, the leaf blades, and the stem and petioles of birch upper foliage, the conductance of the whole shoot and the leaf blades of birch lower foliage, and the conductance of the whole shoot of aspen upper foliage were light sensitive. None of the shoots grown in increased air humidity were significantly light sensitive. We predict that light sensitivity will become more widespread among species in regions where air humidity decreases as a result of global climate change, and vice versa. Low white light always caused the same increase in hydraulic conductance as high white light, and blue and white light always caused an increase in conductance about two times greater than red light, indicating that growth environment did not markedly modify the mechanism of light sensitivity.  相似文献   
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A rhesus monkey (Macaca mulatta), accidentally exposed to vapors of methyl methacrylate for 22 hours was found in a comatose condition. Attempts to revive the animal were unsuccessful. Necropsy revealed a diffusely mottled liver, pulmonary edema, and atelectasis. The thoracic cavities each contained 30 ml of clear yellow fluid. Histopathologic review of the tissues showed central lobular liver necrosis, pulmonary edema, pulmonary emphysema, and atelectasis. Analysis of a blood sample obtained from the monkey 1.5 hours prior to death showed a normal hemogram, but elevated values for serum glutamic oxaloacetic transaminase, serum glutamic pyruvic transaminase, lactate dehydrogenase, phosphohexose isomerase, blood urea nitrogen, and serum sodium. The pathologic findings, laboratory results, and clinical history suggested a diagnosis of methyl methacrylate poisoning.  相似文献   
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At northern latitudes a rise in atmospheric humidity and precipitation is predicted as a consequence of global climate change. We studied several growth and functional traits of hybrid aspen (Populus tremula L.×P. tremuloides Michx.) in response to elevated atmospheric humidity (on average 7% over the ambient level) in a free air experimental facility during three growing seasons (2008-2010) in Estonia, which represents northern temperate climate (boreo-nemoral zone). Data were collected from three humidified (H) and three control (C) plots, and analysed using nested linear models. Elevated air humidity significantly reduced height, stem diameter and stem volume increments and transpiration of the trees whereas these effects remained highly significant also after considering the side effects from soil-related confounders within the 2.7 ha study area. Tree leaves were smaller, lighter and had lower leaf mass per area (LMA) in H plots. The magnitude and significance of the humidity treatment effect - inhibition of above-ground growth rate - was more pronounced in larger trees. The lower growth rate in the humidified plots can be partly explained by a decrease in transpiration-driven mass flow of NO(3) (-) in soil, resulting in a significant reduction in the measured uptake of N to foliage in the H plots. The results suggest that the potential growth improvement of fast-growing trees like aspens, due to increasing temperature and atmospheric CO(2) concentration, might be smaller than expected at high latitudes if a rise in atmospheric humidity simultaneously takes place.  相似文献   
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The green alga Spirogyra varians accumulated antioxidative compounds in response to cold stress. When the algae were transferred from 20°C to 4°C, the amount of phenolic contents and flavonoids in the cell increased 17 times and 30 times, respectively, in 2 months. At this time, the radical scavenging activity of the methanolic extract of S. varians was 238 times higher than that of initial culture. To identify the responsible antioxidants, the methanolic extract was obtained from the algae grown at 4°C. HPLC analysis of the extract showed six compounds newly produced or increased over time. Four of the compounds were successfully purified, and the structures were identified using 1H NMR spectroscopy. The compounds were galloyl derivatives—methyl gallate, 1-O-Galloyl-β-d-glucose, 1,2,3,6-tetra-O-Galloyl-β-d-glucose and 1,2,3,4,6-penta-O-Galloyl-β-d-glucose which are intermediates of the shikimate pathway.  相似文献   
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The CphAII protein from the hyperthermophile Aquifex aeolicus shows the five conserved motifs of the metallo-β-lactamase (MBL) superfamily and presents 28% identity with the Aeromonas hydrophila subclass B2 CphA MBL. The gene encoding CphAII was amplified by PCR from the A. aeolicus genomic DNA and overexpressed in Escherichia coli using a pLex-based expression system. The recombinant CphAII protein was purified by a combination of heating (to denature E. coli proteins) and two steps of immobilized metal affinity chromatography. The purified enzyme preparation did not exhibit a β-lactamase activity but showed a metal-dependent phosphodiesterase activity versus bis-p-nitrophenyl phosphate and thymidine 5′-monophosphate p-nitrophenyl ester, with an optimum at 85°C. The circular dichroism spectrum was in agreement with the percentage of secondary structures characteristic of the MBL αββα fold.  相似文献   
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