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861.
Chemical investigation of the leaves and roots of Selaginella moellendorfii Hieron has resulted in the isolation and characterization of two new flavone glucosides, 7‐O‐(β‐glucopyranosyl(1→2)‐[β‐glucopyranosyl(1→6)]‐β‐glucopyranosyl)flavone‐3′,4′,5,7‐tetraol ( 1 ) and 7‐O‐(β‐glucopyranosyl(1→2)‐[β‐glucopyranosyl(1→6)]‐β‐glucopyranosyl)flavone‐4′,5,7‐triol ( 2 ), two new biflavonoids, 2,3‐dihydroflavone‐5,7,4′‐triol‐(3′→8″)‐flavone‐5″,6″,7″,4′′′‐tetraol ( 3 ) and 6‐methylflavone‐5,7,4′‐triol‐(3′→O→4′′′)‐6″‐methylflavone‐5″,7″‐diol ( 4 ), two new lignans, (7′E)‐3,5,3′,5′‐tetramethoxy‐8 : 4′‐oxyneolign‐7′‐ene‐4,9,9′‐triol ( 5 ) and 3,3′‐dimethoxylign‐8′‐ene‐4,4′,9‐triol ( 6 ), together with two known monolignans, four known lignans, and four known biflavonoids. Their structures were established by spectroscopic means and by comparison with literature values.  相似文献   
862.
863.
A multi‐component catalyst Ni‐VOx/AC (VOx is comprised of V2O5 and VO2, x = 2.18) was synthesized by a wet impregnation method. The synthesized Ni‐VOx/AC shows a superior catalytic effect on de/hydrogenation of Mg. The MgH2+Ni‐VOx/AC composites can absorb 6.2 wt.‐% hydrogen within only 1 min at 150 °C under a hydrogen pressure of 2 MPa and desorb 6.5 wt.‐% hydrogen within 10 min at 300 °C under an initial hydrogen pressure of 1 KPa, which overcomes a critical barrier for practical use of Mg as a hydrogen storage material. A significant decrease of activation energy (Ea) indicates that Ni‐VOx/AC catalyst is highly efficient for Mg de/hydrogenation, which may be ascribed to the synergistic effect of bimetals (metal oxides) and nanocarbon.  相似文献   
864.
In order to evaluate the role of positron emission tomography (PET) with N-methyl-[11C]-2-(4′-methylaminophenyl)-6-hydroxybenzothiazole, also known as Pittsburgh compound B (PIB), in the early diagnosis of Alzheimer’s disease (AD). Clinical data were collected, and PIB PET cerebral imaging was performed in patients with AD (n = 6), mild cognitive impairment (MCI) (n = 7), and elderly, mentally normal controls (NCs) (n = 7). PET images of the subjects were then analyzed. Visual analysis showed that the radioactivity clearance rate in AD patients was significantly different from that found in the NC group. Furthermore, the radioactivity clearance rate 45 min after PIB injection was significantly lower than the NC group. Images from the MCI group presented heterogeneous results, overlapping with those from both the AD and NC groups. Statistical analysis showed that the radioactivity clearance rate during 5–45 min post-injection was significantly lower in the AD group (41–77%) than the control group (75–81%) (P > 0.05) and the MCI group (59–77%). The radioactivity clearance rate in the bilateral parietal lobes, frontal, temporal, and right occipital lobes, and the bilateral corpora striata in MCI group were lower than that in control group (P < 0.05). PIB PET brain imaging can differentiate early AD patients from NCs and may have certain value in identifying patients progressing to MCI.  相似文献   
865.
Li J  Wang F  Zhou Q  Ou Z  Jia H  Deng X  He Y  Wu X 《Helicobacter》2011,16(3):246-251
Background: Polymorphisms of IL‐1 gene cluster are reported to be associated with histological changes and IL‐1β expression in the gastric mucosa in adults, especially in Helicobacter pylori–infected subjects. As H. pylori infecting adults and children own different virulence genotypes, the aim of this study was to investigate whether IL‐1 polymorphisms are risk factors in young children in South China. Materials and Methods: A total of 128 children with peptic symptoms were enrolled in this study. Polymorphisms of IL‐1B‐511 and IL‐1B‐31 were identified by dual fluorescence PCR. Variable number of tandem repeat region in IL‐1RN was detected by conventional PCR and IL‐1β mRNA expression by real‐time PCR ddCT assay. Results: IL‐1B‐31T and IL‐1B‐511C were completely linked in this study. Significant differences of IL‐1B‐511/‐31 genotypes were observed among different clinical outcomes (p = .001). The IL‐1B‐511TT/‐31CC was mostly found in the moderate gastritis and the above (severe gastritis or gastric ulcer) groups, with percentage of 60.7%. While no association was observed between IL‐1RN genotypes and the gastric mucosal histological changes (p = .128). Also no relationships were found between IL‐1 polymorphisms and H. pylori infection or gastric mucosal IL‐1β mRNA expression level. Conclusion: Children with IL‐1B‐511TT/‐31CC may have a risk to develop relatively severe gastric mucosal histological changes in South China.  相似文献   
866.
Biological functions of microRNAs: a review   总被引:1,自引:0,他引:1  
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867.
868.
869.
In this study, we characterized the intratumoral expression of IL-17 and CD8(+) TILs in gastric adenocarcinoma patients after resection and determined the correlation between the survival probability of gastric adenocarcinoma patients and the expression of IL-17 in tumor. Expression of IL-17 and CD8 was assessed by immunohistochemistry, and the prognostic effects of intratumoral IL-17 expression and CD8(+) TILs were evaluated by Cox regression and Kaplan-Meier analysis. Immunohistochemical detection revealed the presence of IL-17 and CD8(+) cells in gastric adenocarcinoma tissue samples (90.6%, 174 out of 192 patients and 96.9%, 186 out of 192 patients, respectively). We have also found that intratumoral IL-17 expression was significantly correlated with age (p=0.004) and that the number of CD8(+)TILs was significantly correlated with UICC staging (p=0.012) and the depth of tumor invasion (p=0.022). The five-year overall survival probability among patients intratumorally expressing higher levels of IL-17 was significantly better than those expressing lower levels of IL-17 (p=0.036). Multivariate Cox proportional hazard analyses revealed that intratumoral IL-17 expression (HR: 0.521; 95% CI: 0.329-0.823; p=0.005) was an independent factor affecting the five-year overall survival probability. We conclude that low levels of intratumoral IL-17 expression may indicate poor prognosis in gastric adenocarcinoma patients.  相似文献   
870.
Shu L  Lou Q  Ma C  Ding W  Zhou J  Wu J  Feng F  Lu X  Luo L  Xu G  Mei H 《Proteomics》2011,11(21):4122-4138
We used proteomic analysis to determine the response of rice plant seedlings to drought-induced stress. The expression of 71 protein spots was significantly altered, and 60 spots were successfully identified. The greatest down-regulated protein functional category was translation. Up-regulated proteins were mainly related to protein folding and assembly. Additionally, many proteins involved in metabolism (e.g. carbohydrate metabolism) also showed differences in expression. cDNA microarray and GC-MS analysis showed 4756 differentially expressed mRNAs and 37 differentially expressed metabolites. Once these data were integrated with the proteomic analysis, we were able to elucidate the metabolic pathways affected by drought-induced stress. These results suggest that increased energy consumption from storage substances occurred during drought. In addition, increased expression of the enzymes involved in anabolic pathways corresponded with an increase in the content of six amino acids. We speculated that energy conversion from carbohydrates and/or fatty acids to amino acids was increased. Analysis of basic metabolism networks allowed us to understand how rice plants adjust to drought conditions.  相似文献   
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