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121.
Yu Zhang Ying Cao Renwen Zhang Xiaxia Zhang Haiying Lu Chihong Wu Na Huo Xiaoyuan Xu 《PloS one》2016,11(11)
BackgroundThe efficacy of direct-acting antiviral agents (DAAs) could be attenuated by the presence of resistance-associated variants (RAVs). The aim of this study was to investigate the natural prevalence of RAVs among Chinese HCV genotype 1b patients and analyze the efficacy of pegylated interferon (PegIFN)/ribavirin (RBV) therapy in patients with and without RAVs at baseline.MethodsDirect sequencing of the HCV NS3, NS5A and NS5B regions was performed in baseline serum samples of 117 DAAs-naïve subjects infected with HCV genotype 1b. The efficacy of PegIFN/RBV therapy in patients with and without RAVs at baseline was analyzed by comparing the response rates between patients with RAVs and patients with wild type virus.ResultsThe incidence of RAVs was 8.00% (8/100) in the NS3 region (T54S, n = 1, 1.00%; R117H, n = 5, 5.00%; S122T, n = 1, 1.00%; S174F, n = 1, 1.00%), 29.91% (32/107) in the NS5A region (L28M, n = 12, 11.21%; R30Q, n = 10, 9.35%; L31M, n = 1, 0.93%; P58S, n = 4, 3.74%; Y93H, n = 8, 7.48%) and 98.15% (106/108) in the NS5B region (L159F, n = 1, 0.93%; C316N, n = 103, 95.37%; A421V, n = 6, 5.56%). The response rates to PegIFN/RBV treatment did not differ between patients with or without RAVs in the NS5A region.ConclusionsPre-existing RAVs, including key RAVs, were detected in Chinese DAAs-naïve patients infected with HCV genotype 1b. IFN-based therapy could be a good option for patients with RAVs, especially key RAVs, at baseline. 相似文献
122.
Melissa M. Singh Adrienne Howard Mary E. Irwin Yin Gao Xiaolin Lu Asha Multani Joya Chandra 《PloS one》2012,7(12)
The BCR-ABL1 oncogene is a tyrosine kinase that activates many signaling pathways, resulting in the induction of chronic myeloid leukemia (CML). Kinase inhibitors, such as imatinib, have been developed for the treatment of CML; however, the terminal, blast crisis phase of the disease remains a clinical challenge. Blast crisis CML is difficult to treat due to resistance to tyrosine kinase inhibitors, increased genomic instability and acquired secondary mutations. Our recent studies uncovered a role for Fyn in promoting BCR-ABL1 mediated cell growth and sensitivity to imatinib. Here we demonstrate that Fyn contributes to BCR-ABL1 induced genomic instability, a feature of blast crisis CML. Bone marrow cells and mouse embryonic fibroblasts derived from Fyn knockout mice transduced with BCR-ABL1 display slowed growth and clonogenic potential as compared to Fyn wild-type BCR-ABL1 expressing counterparts. K562 cells overexpressing constitutively active Fyn kinase were larger in size and displayed an accumulation of genomic abnormalities such as chromosomal aberrations and polyploidy. Importantly, loss of Fyn protected mouse embryonic fibroblast cells from increased number of chromosomal aberrations and fragments induced by BCR-ABL1. Together, these results reveal a novel role for Fyn in regulating events required for genomic maintenance and suggest that Fyn kinase activity plays a role in the progression of CML to blast crisis. 相似文献
123.
Investigation of bathymetry and water quality of Lake Nam Co, the largest lake on the central Tibetan Plateau, China 总被引:3,自引:0,他引:3
Junbo Wang Liping Zhu Gerhard Daut Jianting Ju Xiao Lin Yong Wang Xiaolin Zhen 《Limnology》2009,10(2):149-158
Comprehensive field investigations have been conducted four times on Nam Co, central Tibet, from September 2005 to September
2008. Here, we present the preliminary results focusing on the bathymetric survey and water quality measurements. The isobathic
map shows that Nam Co is a high-altitude, deep lake where a flat and large basin lies in the central part with a water depth
of more than 90 m. Water depth data from the northwestern bank areas of Nam Co provide unquestionable evidence of rising water
levels in the last 3 decades because of the formation of two small islands that were still peninsulas in the 1970s. Water
quality measurements taken at 19 stations during three summer field campaigns (2006, 2007 and 2008) covering almost all of
the lake areas showed that the temperature, pH, dissolved oxygen and electric conductivity of surface water are on average
11.43°C, 9.21, 8.90 mg l−1 and 1,851 μS cm−1, respectively. The surface water shows no obvious spatial variability among all the stations. Vertical fluctuations of profiles,
however, display some differences in thermocline and related parameters, such as pH and dissolved oxygen. According to the
vertical variations of water quality parameters, the water column in relatively deep lake areas of Nam Co could be divided
into three layers with distinctly various features: the epilimnion is from the surface to about 18–20 m depth in which the
parameters are homogeneous with higher temperature and abundant sunlight; the metalimnion ranged from 20–60 m where a thermocline
develops; the deepest layer forms a cold and dark hypolimnion. 相似文献
124.
Changwei Shao Songlin Chen Genbo Xu Xiaolin Liao Yongsheng Tian 《Conservation Genetics》2009,10(3):623-625
Chinese sea perch (Lateolabrax maculates) is one of the most important commercial species of mariculture in China. In this study, we constructed a repeat-enriched
genomic DNA library of L. maculates. Eighteen dinucleotide microsatellite markers were characterized by genotyping 32 samples. The number of alleles ranged from
three to nine, and the observed and expected heterozygosities ranged from 0.4516 to 1.0000 and from 0.4045 to 0.8676, respectively.
Significant deviations from Hardy–Weinberg expectations were detected at four loci and linkage disequilibrium between two
loci was significant after applying Bonferroni correction. The 18 highly polymorphic microsatellite markers should provide
sufficient level of genetic diversity to investigate the population structure and evaluate the breeding strategy in L. maculates. 相似文献
125.
Xiaonan Xue Kangkang Weng Feng Qi Yu Zhang Zaiyu Wang Jazib Ali Donghui Wei Yanming Sun Feng Liu Meixiu Wan Juan Liu Lijun Huo 《Liver Transplantation》2019,9(4)
Morphology and miscibility control are still a great challenge in polymer solar cells. Despite physical tools being applied, chemical strategies are still limited and complex. To finely tune blend miscibility to obtain optimized morphology, chemical steric engineering is proposed to systemically investigate its effects on optical and electronic properties, especially on a balance between crystallinity and miscibility. By changing the alkylthiol side chain orientation different steric effects are realized in three different polymers. Surprisingly, the photovoltaic device of the polymer PTBB‐m with middle steric structure affords a better power conversion efficiency, over 12%, compared to those of the polymers PTBB‐o and PTBB‐p with large or small steric structures, which could be attributed to a more balanced blend miscibility without sacrificing charge‐carrier transport. Space charge‐limited current, atomic force microscopy, grazing incidence wide angle X‐ray scattering, and resonant soft X‐ray scattering measurements show that the steric engineering of alkylthiol side chains can have significant impacts on polymer aggregation properties, blend miscibility, and photovoltaic performances. More important, the control of miscibility via the simple chemical approach has preliminarily proved its great potential and will pave a new avenue for optimizing the blend morphology. 相似文献
126.
Hanyu Huo Yue Chen Jing Luo Xiaofei Yang Xiangxin Guo Xueliang Sun 《Liver Transplantation》2019,9(17)
Solid polymer electrolytes as one of the promising solid‐state electrolytes have received extensive attention due to their excellent flexibility. However, the issues of lithium (Li) dendrite growth still hinder their practical applications in solid‐state batteries (SSBs). Herein, composite electrolytes from “ceramic‐in‐polymer” (CIP) to “polymer‐in‐ceramic” (PIC) with different sizes of garnet particles are investigated for their effectiveness in dendrite suppression. While the CIP electrolyte with 20 vol% 200 nm Li6.4La3Zr1.4Ta0.6O12 (LLZTO) particles (CIP‐200 nm) exhibits the highest ionic conductivity of 1.6 × 10?4 S cm?1 at 30 °C and excellent flexibility, the PIC electrolyte with 80 vol% 5 µm LLZTO (PIC‐5 µm) shows the highest tensile strength of 12.7 MPa. A sandwich‐type composite electrolyte (SCE) with hierarchical garnet particles (a PIC‐5 µm interlayer sandwiched between two CIP‐200 nm thin layers) is constructed to simultaneously achieve dendrite suppression and excellent interfacial contact with Li metal. The SCE enables highly stable Li plating/stripping cycling for over 400 h at 0.2 mA cm?2 at 30 °C. The LiFePO4/SCE/Li cells also demonstrate excellent cycle performance at room temperature. Fabricating sandwich‐type composite electrolytes with hierarchical filler designs can be an effective strategy to achieve dendrite‐free SSBs with high performance and high safety at room temperature. 相似文献
127.
采用^32P示踪和4室根箱方法研究了外生菌根菌丝桥对板栗磷营养和植株间磷素传递作用的效应。给一株板栗幼苗(供体)接种外生菌根真菌美味牛肝菌(Boletus edulis)、褐环乳牛肝菌(Suillus luteus),菌根真菌在侵染供体植物以后其根外菌丝继续生长并侵染邻近的另外一株板栗植株(受体)。同位素示踪试验表明,供体板栗体内的^32P可通过菌丝桥传递给受体板栗,受体植株不仅根中^32P放射性强度高于对照,而且茎中^32P强度也显著高于对照。说明外生菌根真菌在不同板栗植株间形成了菌丝桥,但是菌丝桥传递的磷的数量很有限,仅占供体植株体内总磷量的5%-8%。美味牛肝菌和褐环乳牛肝菌侵染供体板栗植株以后,使植株含磷量、总吸磷量和生物量较对照明显增加。受体板栗幼苗在菌丝桥建立以后其植株含磷量和总吸磷量显著高于对照,但生物量与对照没有显著差别。 相似文献
128.
129.
大黄醇提液抗家兔实验性高脂血症及脂肪肝的实验研究 总被引:11,自引:0,他引:11
目的:检验大黄醇提液抗家兔实验性高脂血症及脂肪肝的影响。方法:将30只雄性健康白兔随机分为5组(n=6):对照组给予基础饲料;模型组给予高脂饲料;三个大黄组给予高脂饲料同时分别灌胃不同药量的大黄醇提液。实验过程中进行一般性指标观测,检测不同阶段五组家兔血脂水平,检测脂肪肝病变程度。结果:大黄醇提液具有降低血清甘油三酯(TG)、低密度脂蛋白胆固醇(LDL-C),升高高密度脂蛋白胆固醇(HDL-C),降低肝细胞脂肪变性的作用。并且大黄醇提液的以上作用存在一定的量效关系。结论:大黄醇提液可降低动脉粥样硬化兔模型的血脂水平、降低脂肪肝的发生发展。 相似文献
130.
Xiao-Li Sun Di Liu Hai-Quan Zhang Na-Xin Huo Rong-Hua Zhou Ji-Zeng Jia 《植物学报(英文版)》2006,48(10):1204-1209
Two powdery mildew resistance genes were Identified from Aegilops tauschll accessions Y201 and Y212 and mapped using two different F2 populations derived from the crosses between susceptible accession Y2272 and Y201, and susceptible accession Y2263 and Y212. Genetic analysis of resistance to powdery mildew Indicated that the resistance of Y201 was controlled by a single dominant gene, whereas the resistance of Y212 was controlled by a single recessive gene. We have temporarily designated these genes as PmY201 and PmY212, respectively. By bulk segregation analysis, six mlcrosatelllte markers Including Xgwm174, cfd26, cfd57, cfdl02, Xgwm583 and Xgwm639 were found to be linked to PraY201 with genetic distances of 5.2, 7.7, 9.6, 12.5, 20.2 and 22.1 cM, respectively. Five SSR markers, including cfd57, Xgwm182, cfd7, cfd102, and cfd12, were found to be linked to PmY212 with distances of 5.6, 7.2, 11.5, 14.7, and 18.5 cM, respectively. According to the locations of the linked markers, the two resistance genes were located In the 5DL region. Based on the chromosomal locations and the resistance patterns of the two genes, we propose that PmY201 and PmY212 are two novel powdery mildew resistance genes, and are suitable for marker-assisted selection. 相似文献