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971.
Zhong Q Zhang Q Wang Z Qi J Chen Y Li S Sun Y Li C Lan X 《Marine biotechnology (New York, N.Y.)》2008,10(3):310-318
Differential expression of genes is crucial to embryogenesis. The analysis of gene expression requires appropriate references
that should be minimally regulated during the embryonic development. To select the most stable genes for gene normalization,
the expression profiles of eight commonly used reference genes (ACTB, GAPDH, rpL17, α-Tub, EF1-α, UbcE, B2M, and 18S rRNA)
were examined during Japanese flounder (Paralichthys olivaceus) embryonic development using quantitative real-time polymerase chain reaction. It was found that all seven mRNA genes appeared
to be developmentally regulated and exhibited significant variation of expression. However, further analyses revealed the
stage-specific expression stability. Hence when normalization using these mRNA genes, the differential and stage-related expression
should be considered. 18S rRNA gene, on the other hand, showed the most stable expression and could be recommended as a suitable
reference gene during all embryonic developmental stages in P. olivaceus. In summary, our results provided not only the appropriate reference gene for embryonic development research in P. olivaceus, but also possible guidance to reference gene selection for embryonic gene expression analyses in other fish species. 相似文献
972.
973.
974.
Dongliang Li Xueying Yang Zheng Zhang Zixin Wang Xiao Qi Yuhua Ruan Yunhua Zhou Chunrong Li Fengji Luo Joseph T. F. Lau 《PloS one》2016,11(1)
Background
The HIV-epidemic among MSM in China has worsened. In this key population, prevalence of HSV-2 and syphilis infection and co-infection with HIV is high.Methods
A longitudinal study was conducted (n = 962) in Beijing, China, with three overlapping cohorts (n = 857, 757 and 760) consisting of MSM that were free from pairs of infections of concern (i.e. HIV-HSV-2, HIV-syphilis, HSV-2-syphilis) at baseline to estimate incidence of HIV, HSV-2, syphilis, and those of co-infection.Results
The incidence of HIV, HSV-2 and syphilis in the overall cohort was 3.90 (95% CI = 2.37, 5.43), 7.87 (95% CI = 5.74, 10.00) and 6.06 (95% CI = 4.18, 7.94) cases per 100 person-years (PYs), respectively. The incidence of HIV-HSV-2, HIV-Syphilis and HSV-2-Syphilis co-infections was 0.30 (95% CI = 0.29, 0.88), 1.02 (95% CI = 0.13, 2.17) and 1.41 (95% CI: 0.04, 2.78) cases per 100 PYs, respectively, in the three sub-cohorts constructed for this study.Conclusions
The incidence of HIV, HSV-2 and syphilis was very high and those of their co-infections were relatively high. Such co-infections have negative impacts on the HIV/STI epidemics. Prevention practices need to take such co-infections into account. 相似文献975.
976.
Generation of a transgenic mouse model with chondrocyte-specific and tamoxifen-inducible expression of Cre recombinase 总被引:2,自引:0,他引:2
Chen M Lichtler AC Sheu TJ Xie C Zhang X O'Keefe RJ Chen D 《Genesis (New York, N.Y. : 2000)》2007,45(1):44-50
Postnatal cartilage development and growth are regulated by key growth factors and signaling molecules. To fully understand the function of these regulators, an inducible and chondrocyte-specific gene deletion system needs to be established to circumvent the perinatal lethality. In this report, we have generated a transgenic mouse model (Col2a1-CreER(T2)) in which expression of the Cre recombinase is driven by the chondrocyte-specific col2a1 promoter in a tamoxifen-inducible manner. To determine the specificity and efficiency of the Cre recombination, we have bred Col2a1-CreER(T2) mice with Rosa26R reporter mice. The X-Gal staining showed that the Cre recombination is specifically achieved in cartilage tissues with tamoxifen-induction. In vitro experiments of chondrocyte cell culture also demonstrate the 4-hydroxy tamoxifen-induced Cre recombination. These results demonstrate that Col2a1-CreER(T2) transgenic mice can be used as a valuable tool for an inducible and chondrocyte-specific gene deletion approach. 相似文献
977.
Choosing appropriate approaches is a key to successfully using biological control measures to accelerate the recovery of eutrophic waterbodies. In this study, we used three biomanipulation approaches—including introducing filter-feeding bivalves, stocking planktivorous fish, replanting submerged macrophytes—as well as an approach that combined all three of these methods in order to investigate their effects on water quality and plankton communities within simulation experiment systems. The experimental results showed that only stocking filter-feeding bivalves or fish could not significantly control the total algal biomass and water nutrient concentrations compared to those of the controls. The cladoceran biomasses were reduced under the treatments of stocking filter-feeding bivalves or fish. However, replanting macrophytes and a combined biological restoration approach could significantly reduce the algal biomass and the nutrient content, and both of these methods increased cladoceran biomass. The results of factor analysis of ten environmental parameters suggested that a combined biological restoration treatment was the most effective at controlling the algal biomass and reducing the nutrient content. In conclusion, combination of biological restoration measures was the best treatment out of the three treatments that were tested, and we suggest that more whole-lake scale experiments are needed. Additionally, designing a combined approach should not be a simple superposition of individual measures, but the measures should be complementary to each other. 相似文献
978.
Aim
The aim of this study was to investigate the prevalence of interankle systolic blood pressure difference (sIAND) and its influencing factors in community population.Methods
This study included 2849 (65.1±9.4 y) subjects. Blood pressure (BPs) of four limbs was simultaneously measured with 4 electronic sphygmomanometers after 10 min rest in supine position. The difference of systolic BP (SBP) between two ankles was calculated as DETASBP. The criterion for abnormal sIAND was ≥10 mmHg of absolute DeltaSBP, in which the criterion for 1o sIAND was 10–19 mmHg and for 2o sIAND was ≥20 mmHg. Age, gender, smoking, hypertension, family histories of hypertension and diabetes were recorded. Fasting blood glucose and lipids, circumference of hip and waist, and body mass index (BMI) were measured.Results
The SBP was higher in the right ankle than in the left ankle (158.9±21.8 vs 157.3±21.6 mmHg, P<0.05) and mean DeltaSBP was 6.08±6.26 mmHg. Similar difference was found in both genders. The prevalence of abnormal was 18.5%, in which, the prevalence 1o sIAND was 15.3% and that of 2o sIAND was 3.1%. Multivariate regression analysis showed that age, waist circumference and blood glucose level were the positive factors for DeltaSBP. The normal upper limit for DeltaSBP was 16.7 mmHg in this population, the prevalence of sIAND by≥16 mmHg was 5.8%.Conclusion
Aging, hypertension, obesity and abnormal glucose metabolism are positive factors for inter-ankle SBP difference. 相似文献979.
蚂蚁筑巢对不同恢复阶段热带森林土壤易氧化有机碳时空动态的影响 总被引:1,自引:0,他引:1
为探明热带森林恢复过程中蚂蚁筑巢对土壤易氧化有机碳(readily oxidizable carbon, ROC)时空动态的影响及机制, 本研究以西双版纳白背桐(Mallotus paniculatus)群落、野芭蕉(Musa acuminata)群落和崖豆藤(Mellettia leptobotrya)群落3种恢复阶段热带森林为研究对象, 设置“蚂蚁筑巢地”与“非巢地”2种处理进行野外控制实验, 对比分析蚁巢和非蚁巢土壤ROC含量的时空变化特征, 并揭示这些变化与土壤微生物生物量碳及理化性质之间的相互关系。结果表明: (1)蚂蚁筑巢显著影响热带森林土壤ROC含量(P < 0.05), 蚁巢土壤ROC含量较非蚁巢提高了14.2%。不同恢复阶段蚁巢与非蚁巢土壤ROC含量大小顺序为: 野芭蕉群落 > 崖豆藤群落 > 白背桐群落。(2)不同恢复阶段热带森林蚁巢与非蚁巢土壤ROC含量均呈单峰型的时间变化趋势(P < 0.05), 最大值出现在6月, 且各月份蚁巢土壤ROC含量均高于非蚁巢。(3)不同恢复阶段热带森林蚁巢和非蚁巢土壤ROC含量均随土层深度增加呈显著递减的垂直变化趋势(P < 0.05), 且蚁巢土壤ROC含量均大于非蚁巢(P < 0.05)。(4)蚂蚁筑巢引起的土壤理化性质变化对土壤ROC含量产生了一定的影响。土壤ROC含量与土壤pH和容重呈显著负相关(P < 0.05), 与土壤有机碳、微生物生物量碳、全氮、铵态氮及硝态氮呈显著正相关(P < 0.05)。土壤微生物生物量碳与总有机碳是蚁巢土壤ROC时空变化的主要贡献者, 而铵态氮、全氮和总有机碳是非蚁巢ROC时空变化的主控因子。因此, 蚂蚁筑巢改变热带森林土壤微生物量(如微生物生物量碳)及土壤理化性质(如总有机碳、铵态氮与全氮等), 进而显著影响土壤ROC的时空动态。 相似文献
980.
Xuan-Ming Zhang Li-Wen Han Shan-Shan Zhang Xiao-Bin Li Qiu-Xia He Jian Han 《Nucleosides, nucleotides & nucleic acids》2019,38(3):203-217
In this study, we investigated the metabonomic profiles of Apostichopus japonicus using an LC-MS-based method in conjunction with multivariate data analysis. Based on the PLS-DA model, 85 differential metabolites (VIP value >1.0) were obtained from viscera and body wall samples. The MS/MS and NMR experiments were used for the qualitative identification of the characteristic peaks. Sphingoid-based nucleoside analogues were the main components in Chinese A. japonicus viscera. Our findings demonstrate that A. japonicus viscera contain a large number of compounds that may have applications as nutraceuticals or pharmaceuticals. 相似文献