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排序方式: 共有527条查询结果,搜索用时 31 毫秒
81.
Serio C Esposito F Masiello G Pavese G Calvello MR Grieco G Cuomo V Buijs HL Roy CB 《Applied optics》2008,47(21):3909-3919
We evaluate the spectral quality, radiometric noise, and retrieval performance of a Fourier transform infrared spectrometer, which has been developed for recording spectrally resolved observations in a region of the spectrum which is important both for the science of Earth's climate and applications, such as the remote sensing of temperature and atmospheric gas species. This spectral region extends from 100 to 1600 cm(-1) and encompasses the two fundamental, rotation and vibration, absorption bands of water vapor. The instrument is a customized version of a Bomem AERI (Atmospheric Emitted Radiance Interferometer) spectrometer, whose spectral coverage has been extended in the far infrared with the use of uncooled pyroelectric detectors. Retrieval examples for water vapor and temperature profiles are shown, which also allow us to intercompare the retrieval performance of both H(2)O vibration and rotation bands. 相似文献
82.
Zhou TB Qin YH Li ZY Xu HL Zhao YJ Lei FY 《International journal of molecular sciences》2012,13(3):2769-2782
This study was performed to investigate the association of prohibitin with renal interstitial fibrosis (RIF) lesion and to explore the association of all-trans retinoic acid (ATRA) treatment with prohibitin expression in RIF rats. Rats were divided into three groups: the sham operation group (SHO), the model group subjected to unilateral ureteral obstruction (UUO), and the model group treated with ATRA (GA). Renal tissues were collected at 14 and 28 days after surgery, and the relevant indicators were detected. In comparison with the SHO group, the RIF index in the UUO group was markedly elevated (p < 0.01), and the RIF index in the GA group was alleviated compared with that in the UUO group (p < 0.01). Compared with the SHO group, the expression of prohibitin (protein or mRNA) in the UUO group was significantly reduced (each p < 0.01). Prohibitin expression in the GA group was markedly increased when compared with that in the UUO (p < 0.01). The expression of TGF-β1 (protein and mRNA), protein expressions of Col-IV, fibronectin, α-SMA and cleaved Caspase-3, ROS generation and cell apoptosis index in the UUO group were markedly higher than those in the SHO group (all p < 0.01), and their expressions in the GA group were markedly down-regulated compared to those in the UUO group (all p < 0.01, respectively). The protein expression of prohibitin was negatively correlated with the RIF index, protein expression of TGF-β1, Col-IV, fibronectin, α-SMA or cleaved Caspase-3, ROS generation and the cell apoptosis index (each p < 0.01). In conclusion, lower expression of prohibitin is associated with the RIF, and ATRA treatment is associated with increased prohibitin, which can prevent the progression of RIF. 相似文献
83.
Lin CL Chen RF Chen JY Chu YC Wang HM Chou HL Chang WC Fong Y Chang WT Wu CY Chiu CC 《International journal of molecular sciences》2012,13(5):6236-6245
Caffeic acid (CA), a natural phenolic compound, is abundant in medicinal plants. CA possesses multiple biological effects such as anti-bacterial and anti-cancer growth. CA was also reported to induce fore stomach and kidney tumors in a mouse model. Here we used two human lung cancer cell lines, A549 and H1299, to clarify the role of CA in cancer cell proliferation. The growth assay showed that CA moderately promoted the proliferation of the lung cancer cells. Furthermore, pre-treatment of CA rescues the proliferation inhibition induced by a sub-IC(50) dose of paclitaxel (PTX), an anticancer drug. Western blot showed that CA up-regulated the pro-survival proteins survivin and Bcl-2, the down-stream targets of NF-κB. This is consistent with the observation that CA induced nuclear translocation of NF-κB p65. Our study suggested that the pro-survival effect of CA on PTX-treated lung cancer cells is mediated through a NF-κB signaling pathway. This may provide mechanistic insights into the chemoresistance of cancer calls. 相似文献
84.
HL Chen H Seol KJ Brown H Gordish-Dressman A Hill V Gallo R Packer Y Hathout 《International journal of molecular sciences》2012,13(7):9380-9399
To bring insights into neurofibroma biochemistry, a comprehensive secretome analysis was performed on cultured human primary Schwann cells isolated from surgically resected plexiform neurofibroma and from normal nerve tissue. Using a combination of SDS-PAGE and high precision LC-MS/MS, 907 proteins were confidently identified in the conditioned media of Schwann cell cultures combined. Label free proteome profiling revealed consistent release of high levels of 22 proteins by the four biological replicates of NF1 Schwann cell cultures relative to the two normal Schwann cell cultures. Inversely, 9 proteins displayed decreased levels in the conditioned media of NF1 relative to normal Schwann cells. The proteins with increased levels included proteins involved in cell growth, angiogenesis and complement pathway while proteins with decreased levels included those involved in cell adhesion, plasminogen pathway and extracellular matrix remodeling. Retinoic acid receptor responder protein-1 (RARRES1), previously described as an integral membrane tumor suppressor, was found exclusively secreted by NF1 Schwann cells but not by normal Schwann cells. All-trans retinoic acid modulated secretion of RARRES1 in a dose dependent manner. This study shows altered secretion of key proteins in NF1 derived Schwann cells. The potential implication of these proteins in neurofibroma biology is discussed. 相似文献
85.
Rickard JW Wiegand BR Pompeu D Hinson RB Gerlemann GD Disselhorst R Briscoe ME Evans HL Allee GL 《Meat science》2012,90(3):643-652
The objective of this study was to evaluate dietary corn distiller's dried grains with solubles (DDGS), ractopamine hydrochloride (RAC), and conjugated linoleic acid (CLA) on growth performance, carcass and fat quality, and shelf-life of fresh pork from finishing pigs. Barrows (n = 72) were fed one of eight treatments consisting of two diet sources (corn-soy and corn-soy + 20% DDGS), two levels of RAC (0 and 7.4 ppm), and two levels of CLA (0 and 0.6%) for 28 days. Loins were portioned (n = 3) into one of three storage conditions (fresh, cold, frozen); each followed with seven days of retail display. Feeding RAC improved ADG and G:F (P < 0.05), whereas DDGS decreased belly fat firmness (P < 0.05). Dietary DDGS increased total polyunsaturated fatty acids in jowl and belly samples and increased Iodine Value (IV) (P < 0.05), but addition of CLA decreased IV. Dietary DDGS, RAC, or CLA had minimal impact on pork quality following varied storage methods. 相似文献
86.
87.
Prevalence of antibiotic resistance genes in the bacterial flora of integrated fish farming environments of pakistan and Tanzania 总被引:1,自引:0,他引:1
The use of a wide variety of antimicrobials in human and veterinary medicine, including aquaculture, has led to the emergence of antibiotic resistant pathogens. In the present study, bacteria from water, sediments, and fish were collected from fish farms in Pakistan and Tanzania with no recorded history of antibiotic use. The isolates were screened for the presence of resistance genes against various antimicrobials used in aquaculture and animal husbandry. Resistant isolates selected by disk diffusion and genotyped by Southern hybridization were further screened by polymerase chain reaction (PCR) and amplicon sequencing. The prominent resistance genes identified encoded tetracycline [tetA(A) and tetA(G)], trimethoprim [dfrA1, dfrA5, dfrA7, dfrA12, and dfrA15], amoxicillin [bla(TEM)], streptomycin [strA-strB], chloramphenicol [cat-1], and erythromycin resistance [mefA]. The int1 gene was found in more than 30% of the bacterial isolates in association with gene cassettes. MAR indices ranged from 0.2 to 1. The bla(NDM-1) gene was not identified in ertapenem resistant isolates. It is hypothesized that integrated fish farming practices utilizing domestic farm and poultry waste along with antibiotic residues from animal husbandry may have contributed to a pool of resistance genes in the aquaculture systems studied. 相似文献
88.
This study is about reaction condition optimization and exploration of the general pathway of GSH-participating Maillard reaction. Response surface methodology (RSM) is used to define the reaction condition for optimal meat flavor product generation from synthetic oligopeptides via the Maillard reaction. The optimal reaction condition is: (A) temperature: 131.53 °C, (B) reaction time: 94.85 min, (C) volume of 0.2M phosphate buffer: 49.61 mL and (D) initial pH of reactants: 4.79. The priority sequence is: A > D > C > B, and the verification score was 9.1. A preliminarily pathway scheme using CAMOLA has been constructed to suggest a reaction mechanism for meat-like aroma product formation. In addition, a 2-pathway and 3-stage formation scheme of the GSH-participating Maillard reaction has been constructed. 相似文献
89.
Muoki PN de Kock HL Emmambux MN 《Journal of the science of food and agriculture》2012,92(8):1771-1779
BACKGROUND: The nutritional quality of cassava complementary porridge was improved through extrusion cooking and compositing with either defatted or full fat soy flour (65:35 w/w), and product acceptability by mothers with children of the target population was evaluated. RESULTS: The protein digestibility‐corrected amino acid score (PDCAAS) of extrusion‐ and conventionally cooked composite porridges was within the recommendations for complementary foods. The kinetics of starch digestibility showed that all porridges had a rapid rate of starch digestibility, but the rate was lower when defatted soy flour was added and lowest when full fat soy flour was added. The formation of amylase‐lipid complexes as shown by X‐ray diffraction and differential scanning calorimetry can be attributed to the lower digestibility of extrusion‐cooked porridge with full fat soy flour. If fed thrice per day, extrusion‐cooked porridge with defatted or full fat soy flour would meet the energy, protein and available lysine requirements of a child aged 6–8 months receiving low or average nutrients from breast milk. All porridges were well received by Mozambican mothers who use cassava as a staple food. The mean scores for sensory liking of all porridges were 3 and above on a five‐point hedonic scale. CONCLUSION: Extrusion‐cooked cassava/soy flour porridges have good potential for use as high‐energy/high‐protein complementary foods and have acceptable sensory properties. Copyright © 2012 Society of Chemical Industry 相似文献