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121.
Paraoxonase is an HDL-associated enzyme that plays a preventive role against oxidative stress, which is thought to contribute
to cancer development. PON1 activity varies widely among individuals, which is in part related to two common nonsynonymous
polymorphisms in the PON1 gene (Q192R and L55M). The polymorphisms in PON1 have been implicated in cancer risk. However, results
from the studies to date have been conflicting. To clarify the association, a meta-analysis was performed for 7,073 cases
and 9,520 controls from 25 published case–control studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used
to assess the strength of the association. Significant associations between PON1-L55M but not Q192R polymorphism and total
cancer were observed from all the comparisons. In stratified analyses, PON1-55M allele was a risk factor for breast cancer.
Similarly, increased risk was observed for prostate cancer (OR = 1.18, 95% CI: 1.01–1.36, P
heterogeneity = 0.260) and Caucasian population (OR = 1.18, 95% CI: 1.02–1.38, P
heterogeneity = 0.1) of the LM genotype, compared with the LL genotype. For PON1-Q192R polymorphism, PON1-192R allele was a decreased risk
factor for cancer in the Asian group (RR vs QQ: OR = 0.61, 95% CI: 0.38–0.98, P
heterogeneity = 0.268; QR vs QQ: OR = 0.71, 95% CI: 0.52–0.96, P
heterogeneity = 0.130; RR + QR vs QQ: OR = 0.71, 95% CI: 0.53–0.95, P
heterogeneity = 0.135). Although some modest bias could not be eliminated, this meta-analysis suggests that the PON1-55M allele is a risk factor for the development of cancer, in particular for breast cancer. Future studies with larger sample
sizes are warranted to further evaluate these associations. 相似文献
122.
Late-acting self-incompatibility in tea plant (<Emphasis Type="Italic">Camellia sinensis</Emphasis>)
The self-incompatibility of tea plant (Camellia sinensis (L.) O. Kuntze) was studied with the methods of aniline blue fluorescence assay and paraffin sections. The characteristics
of pollen tube elongation after hand pollination was analyzed in 4 tea cultivars, including ‘Keemenzhong’, ‘Longjing-changye’,
‘Fuding-dabaicha’ and ‘Yabukita’, under self-pollination and cross-pollination, respectively. Although there were some difference
among cultivars, pollen tubes elongated through the style and reach the ovary successfully at 48 h after pollination for both
cross- and self-pollen tubes in all the four cultivars of tea. Pollen tubes entered into the ovule micropyles, however, only
for cross-pollination, but not for self-pollination. Pollen tubes of selfing plants, failed in fertilizing, seemed have some
difficulties to enter the ovule. All of which indicated that the self-incompatibility of tea plant is a late-acting self-incompatibility
system (LSI) or an ovarian sterility (OS), in which the self incompatibility was due to none self pollen tube penetrating
into the ovule and no fertilization. 相似文献
123.
Zhao X. Chen L. Ren Q. Wu Z. Fang S. Jiang Y. Chen Y. Zhong Y. Wang D. Wu J. Zhang G. 《Applied Biochemistry and Microbiology》2021,57(3):344-350
Applied Biochemistry and Microbiology - A pyridine-transforming strain P2 was isolated from sewage collected from Guangzhou oil stain field(China).According to the system analysis, it was... 相似文献
124.
125.
126.
Linsheng Liu Jiye Aa Guangji Wang Bei Yan Xinwen Wang Bei Cao Mengjie Li Yuanting Zheng Fang Zhou Zimei Wu 《Analytical biochemistry》2010,406(2):105-6697
In metabolomic research, blood plasma and serum have been considered to possess similar compositions and properties. Their perceived equivalence has resulted in researchers choosing arbitrarily between serum and plasma for analysis. Here, routine serum and plasma were prepared and their low-molecular-weight compounds were determined using gas chromatography/time-of-flight mass spectrometry. Principal components analysis was applied to process the acquired data, and marked differences in metabolite profiles were observed between serum and plasma. Of the 72 identified compounds, 36 (50%) discriminate serum from plasma, with 29 and 7 metabolites showing a significantly higher abundance (t test, P < 0.05) in serum and plasma, respectively. Incubation of blood had distinct effects on the analyte peak areas, with the effects being more pronounced for plasma than for serum and more pronounced for a shorter incubation than for a longer incubation. These results highlight the importance in choosing serum or plasma as the analytical sample and in stipulating the incubation time. Because incubation affected the analyte peak areas less in serum than in plasma, we recommend serum as the sample of choice in metabolomic studies. 相似文献
127.
北沙参中佛手柑内酯的分离鉴定及体外抗肿瘤活性的初步测定 总被引:2,自引:0,他引:2
北沙参为传统的中药材,来源于伞形科(Umbelliferae)植物珊瑚菜(Glehnia littoralis Fr. Schmidt ex Miq. )的干燥根,具有养阴清肺、益胃生津的功效[1],其道地产地为山东莱阳. 相似文献
128.
Background
Bryopsis hypnoides Lamouroux is a siphonous green alga, and its extruded protoplasm can aggregate spontaneously in seawater and develop into mature individuals. The chloroplast of B. hypnoides is the biggest organelle in the cell and shows strong autonomy. To better understand this organelle, we sequenced and analyzed the chloroplast genome of this green alga.Principal Findings
A total of 111 functional genes, including 69 potential protein-coding genes, 5 ribosomal RNA genes, and 37 tRNA genes were identified. The genome size (153,429 bp), arrangement, and inverted-repeat (IR)-lacking structure of the B. hypnoides chloroplast DNA (cpDNA) closely resembles that of Chlorella vulgaris. Furthermore, our cytogenomic investigations using pulsed-field gel electrophoresis (PFGE) and southern blotting methods showed that the B. hypnoides cpDNA had multimeric forms, including monomer, dimer, trimer, tetramer, and even higher multimers, which is similar to the higher order organization observed previously for higher plant cpDNA. The relative amounts of the four multimeric cpDNA forms were estimated to be about 1, 1/2, 1/4, and 1/8 based on molecular hybridization analysis. Phylogenetic analyses based on a concatenated alignment of chloroplast protein sequences suggested that B. hypnoides is sister to all Chlorophyceae and this placement received moderate support.Conclusion
All of the results suggest that the autonomy of the chloroplasts of B. hypnoides has little to do with the size and gene content of the cpDNA, and the IR-lacking structure of the chloroplasts indirectly demonstrated that the multimeric molecules might result from the random cleavage and fusion of replication intermediates instead of recombinational events. 相似文献129.
Akira Kubota Fang He Manabu Kawase Gaku Harata Masaru Hiramatsu Hisakazu Iino 《Current microbiology》2011,62(1):71-77
This study was conducted to evaluate the potential association between intestinal bifidobacteria and Japanese cedar pollinosis
(JCPsis) and possible influences of probiotic intervention. In this study, fecal samples were the collected from 29 JCPsis
patients. The qualitative and quantitative analyses of fecal bifidobacteria were conducted by quantitative real-time PCR with
16S rRNA-gene-targeted species-specific primers before cedar pollen spread and after a 10-week intervention with fermented
milk prepared with Lactobacillus GG and L. gasseri TMC0356 during pollen spread. Each JCPsis patient had a unique diversity of bifidobacteria, which varied qualitatively and
quantitatively in an individual-dependent manner during pollen spread. The serum IgE concentration of JCPsis patients with
more than 3 detectable Bifidobacterium species was significantly lower than that of patients with less than 2 detected species. The prevalence of B. adolescentis, B. longum, and B. catenulatum increased after probiotic intervention, although the changes were not statistically significant. These results suggest that
lower diversity of intestinal Bifidobacterium species might be a pathological aspect of JCPsis. The diversity of intestinal bifidobacteria could be a prospective target
for using probiotics in the management of IgE-mediated allergic disorders including JCPsis. 相似文献
130.
The functional modulation of lymphatic vessels may be closely associated with intact structures of the vagus nerve. In the present study, the vagotomy was done in Wistar rat to investigate the effect of vagus nerves on dynamic changes of mesenteric lymphatic vessels. After denervation, the mesenteric lymphatics showed significant decreases in contraction rate, diameter in the static state and overall contractile activity under a microscopic observation. The lymphatic contraction rhythm and valve movement became irregular and inconsistent. These findings indicated that the lymphatic innervation might be an important factor for active lymph formation and transportation. 相似文献