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排序方式: 共有258条查询结果,搜索用时 78 毫秒
41.
Jae-Hoon HwangJeong-A Choi Reda A.I. Abou-Shanab Booki MinHocheol Song Yongje Kim Eung Seok LeeByong-Hun Jeon 《Bioresource technology》2011,102(2):1051-1058
Anaerobic fermentation for hydrogen (H2) production was studied in a two-stage fermentation system fed with different ripened fruit feedstocks (apple, pear, and grape). Among the feedstocks, ripened apple was the most efficient substrate for cumulative H2 production (4463.7 mL-H2 L−1-culture) with a maximum H2 yield (2.2 mol H2 mol−1 glucose) in the first stage at a hydraulic retention time (HRT) of 18 h. The additional cumulative biohydrogen (3337.4 mL-H2 L−1-culture) was produced in the second stage with the reused residual substrate from the first stage. The major byproducts in this study were butyrate, acetate, and ethanol, and butyrate was dominant among them in all test runs. During the two-stage system, the energy efficiency (H2 conversion) obtained from mixed ripened fruits (RF) increased from 4.6% (in the first stage) to 15.5% (in the second stage), which indicated the energy efficiency can be improved by combined hydrogen production process. The RF could be used as substrates for biohydrogen fermentation in a two-stage (dark/dark) fermentation system. 相似文献
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Large‐scale automated function prediction of protein sequences and an experimental case study validation on PTEN transcript variants 下载免费PDF全文
44.
Lukas?J.?MotlochEmail author Tina?Gebing Sara?Reda Astrid?Schwaiger Martin?Wolny Uta?C.?Hoppe 《The Journal of membrane biology》2016,249(4):577-584
Mitochondrial Ca2+ uptake (mCa2+ uptake) is thought to be mediated by the mitochondrial Ca2+ uniporter (MCU). UCP2 and UCP3 belong to a superfamily of mitochondrial ion transporters. Both proteins are expressed in the inner mitochondrial membrane of the heart. Recently, UCP2 was reported to modulate the function of the cardiac MCU related channel mCa1. However, the possible role of UCP3 in modulating cardiac mCa2+ uptake via the MCU remains inconclusive. To understand the role of UCP3, we analyzed cardiac mCa1 single-channel activity in mitoplast-attached single-channel recordings from isolated murine cardiac mitoplasts, from adult wild-type controls (WT), and from UCP3 knockout mice (UCP3–/–). Single-channel registrations in UCP3?/? confirmed a murine voltage-gated Ca2+ channel, i.e., mCa1, which was inhibited by Ru360. Compared to WT, mCa1 in UCP3?/? revealed similar single-channel characteristics. However, in UCP3?/? the channel exhibited decreased single-channel activity, which was insensitive to adenosine triphosphate (ATP) inhibition. Our results suggest that beyond UCP2, UCP3 also exhibits regulatory effects on cardiac mCa1/MCU function. Furthermore, we speculate that UCP3 might modulate previously described inhibitory effects of ATP on mCa1/MCU activity as well. 相似文献
45.
Sixty-eight bacterial cultures were isolated from 5 archaeological soils in Egypt. It is necessary to characterize bacteria from ancient temples to develop protection programs for such archaeological places. Purified bacterial cultures were then tested for their capability to inhibit some multi-drug resistant (MDR) pathogenic bacteria including Staphylococcus aureus, Listeria monocytogenes, Bacillus cereus, Escherichia coli and Klebsiella pneumoniae. Among the most active 10 antibacterial isolates, only one isolate designated as S5I4 was selected, characterized and identified as belonging to Bacillus amyloliquefaciens. The strain identification was confirmed by amplification of its 16S rRNA gene. The partial nucleotide sequence of the amplified 16S rRNA gene of the tested strain was submitted in GenBank with accession number AB813716. The physical and nutritional parameters were optimized to improve the production of antimicrobial agents by the B. amyloliquefaciens S5I4. The maximum antagonistic effect of this strain against the tested MDR pathogenic bacteria was achieved in presence of 1% galactose and 0.5% yeast extract at 37°C and pH 7.0 after 48 h incubation. The antibacterial compounds of B. amyloliquefaciens S5I4 were extracted, purified and characterized using spectroscopic analysis (IR, UV, proton NMR and MS). The compound having inhibitory activity was identified as butanedioic acid, octadecyl,1(1carboxy1methylethyl) 4octyl ester. 相似文献
46.
A modified procedure for the extraction of betacyanin fromAmaranthus seedlings is described. Application of this modification increased the absorbance of cytokinin-treatedAmaranthus explants in most cases. The modifiedAmaranthus test is compared with the soybean callus test in the bioassay of kinetin, 6-benzylaminopurine, and 6(δ,δ-dimethylallyl) aminopurine. 相似文献
47.
Inhibitory effect of molybdenum and vanadium salts on aflatoxin B1 synthesis by Aspergillus flavus 总被引:2,自引:0,他引:2
The effects of the elements zinc, manganese, iron, copper, molybdenum, and vanadium, added in various salt forms, on mycelial weights and aflatoxin B1 accumulation in the mycelium of Aspergillus flavus were investigated in liquid shake cultures. Ammonium heptamolybdate, when added to a complete medium at concentrations of 50-100 mg/L, appreciably reduced aflatoxin B1 accumulation without affecting growth of the fungus. Sodium molybdate and sodium monovanadate also reduced aflatoxin B1 yields without affecting mycelial growth but to a lesser extent. The addition of zinc sulphate stimulated aflatoxin B1 production in all media used. The influence of the other trace elements on aflatoxin production depended on the level of trace elements present in the basal medium. In general, manganese chloride had a stimulatory effect, whereas copper sulphate depressed yields. Mycelial levels of aflatoxin had peaked and then declined before mycelial dry weights had reached maximum. High yields of aflatoxin B1 were obtained in media having a final pH as low as pH 2.8. 相似文献
48.
OBJECTIVE: To evaluate the significance of a diagnosis of atypical glandular cells, favor endometrial origin (AGC-EM), using cytohistologic correlation. STUDY DESIGN: A retrospective search identified 90 cervicovaginal smears (vaginal pool) with a diagnosis of AGC-EM, in 2 tertiary care medical centers between January 1998 and December 2002. RESULTS: Forty-six (51%) were conventional preparations and 44 (49%) were liquid-based monolayers (SurePath, TriPath Imaging Inc., Burlington, North Carolina, U.S.A.). Follow-up biopsies were available in 55 of 90 (61%) cases, 15 of 90 (17%) cases had cytology follow-up, and 20 of 90 (22%) were lost to follow-up. The patients ranged in age from 30 to 86 years (mean, 56); 56 of 90 (62%) were > 50 years. Among the patients who underwent biopsy, 22 (40%) had a clinically significant lesion, including 10 (18%) endometrial adenocarcinomas, 8 (15%) endometrial hyperplasias and 4 (7%) high grade squamous intraepithelial lesion/squamous cell carcinoma, nonkeratinizing type. The remaining 33 patients had benign histology, including benign endometrium, endometrial polyp, tubal metaplasia, cystic endometrial atrophy and cervical microglandular hyperplasia. Of the patients with cytologic follow-up, 2 had Pap smears showing atypical squamous cells of undetermined significance, while the remainder had negative results. CONCLUSION: In our study population, 40% (22 of 55) of women who underwent biopsy following a diagnosis of AGC-EM had significant uterine lesions, with the majority of the lesions endometrial in origin. Patients with a diagnosis of AGC-EM, especially those > 50, should be followed closely, and endometrial sampling should be included in their initial workup. 相似文献
49.
OBJECTIVE: To evaluate the accuracy of fine needle aspiration biopsy (FNAB) in the diagnosis of vertebral lesions. STUDY DESIGN: Eighty-nine FNAB cases of vertebral lesions from January 1996 to December 2001 were retrieved from the Allegheny General Hospital laboratory information system. The cases were reviewed and correlated with clinical findings, including previous clinical history, primary site of malignancy and final pathologic diagnosis. RESULTS: ENAB diagnoses were malignant in 43 cases, benign in 35, suspicious in 1, unsatisfactory in 7 and false negative in 3. Previous clinical history included malignancy (37 patients), osteomyelitis and systemic disease (11), and nonspecific or no history (41). In 34 cases (38.2%) both aspirates and core biopsies were available, and the diagnoses correlated in 29/34 cases (85%). Surgical or core biopsies in the unsatisfactory/suspicious group showed malignancy in 4 cases (50%). The sensitivity of FNAB of vertebral lesions was 96%, specificity 100%, positive predictive value 100% and negative predictive value 92%, with no false positive cases. CONCLUSION: FNAB of vertebral lesions is an effective, sensitive and specific procedure in the diagnostic workup of a patient with or without a prior history of malignancy. Surgical pathology examination, including core biopsies of unsatisfactory or suspicious lesions, can further improve the diagnostic yield. 相似文献
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