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991.
Yu H Braun P Yildirim MA Lemmens I Venkatesan K Sahalie J Hirozane-Kishikawa T Gebreab F Li N Simonis N Hao T Rual JF Dricot A Vazquez A Murray RR Simon C Tardivo L Tam S Svrzikapa N Fan C de Smet AS Motyl A Hudson ME Park J Xin X Cusick ME Moore T Boone C Snyder M Roth FP Barabási AL Tavernier J Hill DE Vidal M 《Science (New York, N.Y.)》2008,322(5898):104-110
Current yeast interactome network maps contain several hundred molecular complexes with limited and somewhat controversial representation of direct binary interactions. We carried out a comparative quality assessment of current yeast interactome data sets, demonstrating that high-throughput yeast two-hybrid (Y2H) screening provides high-quality binary interaction information. Because a large fraction of the yeast binary interactome remains to be mapped, we developed an empirically controlled mapping framework to produce a "second-generation" high-quality, high-throughput Y2H data set covering approximately 20% of all yeast binary interactions. Both Y2H and affinity purification followed by mass spectrometry (AP/MS) data are of equally high quality but of a fundamentally different and complementary nature, resulting in networks with different topological and biological properties. Compared to co-complex interactome models, this binary map is enriched for transient signaling interactions and intercomplex connections with a highly significant clustering between essential proteins. Rather than correlating with essentiality, protein connectivity correlates with genetic pleiotropy. 相似文献
992.
Kimchi-Sarfaty C Oh JM Kim IW Sauna ZE Calcagno AM Ambudkar SV Gottesman MM 《Science (New York, N.Y.)》2007,315(5811):525-528
Synonymous single-nucleotide polymorphisms (SNPs) do not produce altered coding sequences, and therefore they are not expected to change the function of the protein in which they occur. We report that a synonymous SNP in the Multidrug Resistance 1 (MDR1) gene, part of a haplotype previously linked to altered function of the MDR1 gene product P-glycoprotein (P-gp), nonetheless results in P-gp with altered drug and inhibitor interactions. Similar mRNA and protein levels, but altered conformations, were found for wild-type and polymorphic P-gp. We hypothesize that the presence of a rare codon, marked by the synonymous polymorphism, affects the timing of cotranslational folding and insertion of P-gp into the membrane, thereby altering the structure of substrate and inhibitor interaction sites. 相似文献
993.
994.
日粮锌水平对断奶仔猪生产性能、免疫器官及组织锌的影响 总被引:16,自引:0,他引:16
选用40头28日龄断奶约滇陆(YN1)杂交仔猪进行为期5周的试验,试验仔猪随机分为5个组(锌添加量分别为80,240,1 000,3 000和5 000 mg/kg),研究锌对断奶仔猪生产性能、免疫器官生长发育及组织锌沉积的影响。结果表明:适量高锌(1 000 mg/kg和3 000 mg/kg)能显著提高仔猪生产性能(P<0.05);补锌对免疫器官指数无影响(P>0.05);高锌增加肝脏、肾脏、趾骨、血清和毛发中锌含量(P<0.01);而背最长肌、扁桃体和胸腺锌含量则只有在添加5 000 mg/kg日粮锌时含量显著上升(P<0.05)。脾脏锌含量则随着高锌的添加变化差异不显著(P>0.05)。低锌添加(80 mg/kg和240 mg/kg)对机体各组织中锌含量无显著影响(P>0.05)。 相似文献
995.
工厂化农业企业选择农业园区的模糊评价方法 总被引:1,自引:0,他引:1
依据农业园区外围设施因素,即自然环境状况、水电供应情况和温室质量、通讯条件、与目标市场的距离和交通运输条件、生活服务条件等,和优惠政策因素,包括当地政府的优惠政策和园区优惠政策等,制定了农业园区的评价标准,并由专家评价小组对园区的每个因素进行评价。应用模糊数学方法建立了数学模型,对专家评价结果进行了模糊综合评价,并对结果进行了确定性处理,最后,得到了农业园区综合评价等级。实例分析结果表明,用模糊评价方法选择农业园区,可使工厂化农业企业选出适合自己企业项目发展的农业园区。 相似文献
996.
本文在对红花蛋白的提取方法作了大量研究的基础上。指明了采用等电沉淀法提取红花蛋白时,pH值,温度,籽粕含油量,不同浸提液与蛋白质得率的关系。同时,用多种方法对红花蛋白作了较全面的利用价值的评价。 相似文献
997.
菠菜胆碱单氧化酶(CMO)基因的克隆及在大肠杆菌中的诱导表达 总被引:1,自引:0,他引:1
甘氨酸甜菜碱是一种非毒性的渗透调节物质 ,在植物体内是以胆碱为底物 ,经两步氧化而合成的 .菠菜中 ,催化第一步反应的酶为胆碱单氧化酶 (CholineMonooxygenase ,CMO) .为了研究胆碱单氧化酶基因的功能以及转基因植物的抗逆能力 ,在 30 0mmol L高盐浓度 (n(NaCl)∶n(CaCl2 ) =5 7∶1)的条件下 ,作者分离纯化了菠菜mRNA ,经RT PCR得到全长 (1.3kb)胆碱单氧化酶 (CMO)cDNA ,与已经报道的基因序列相比较 ,同源性为 99% .根据其核苷酸序列推导得到了氨基酸序列 .将PCR纯化产物与pET 30a+ 连接 ,构建了重组表达载体pETCMO ,并转化到大肠杆菌BL2 1(DE3) ,经IPTG诱导获得高效表达 . 相似文献
998.
999.
BackgroundRabies is a viral disease that causes severe neurological manifestations both in humans and various mammals. Although inactivated and/or attenuated vaccines have been developed and widely used around the world, there are still concerns with regard to their safety, efficacy, and costs.ObjectiveAs demand has grown for a new rabies vaccine, we have developed a new vesicular stomatitis viruses (VSVs) based rabies vaccine that replaces glycoproteins with rabies virus (RABV) glycoprotein (GP), or so-called VSV/RABV-GP.MethodsVSV/RABV-GP production was measured by sandwich ELISA. The generation of VSV/RABV-GP was evaluated with GP-specific antibodies and reduced transduction with GP-specific neutralizing antibodies. Virus entry was quantified by measuring the luciferase levels at 18-h post-transduction. BALB/c mice (three groups of six mice each) were intraperitoneally immunized with PBS, RABA, or VSV/RABV-GP at 0 and 14 days. At 28 days post-immunization serology was performed. Statistical significance was calculated using the Holm–Sidak multiple Student’s t test.ResultsMice immunized with VSV/RABV-GP produced IgM and IgG antibodies, whereas IgM titers were significantly higher in mice immunized with VSV/RABV-GP compared to inactivated RABV. The secretion profiles of IgG1 and IgG2a production suggested that VSV/RAVB-GP induces the T helper cell type-2 immune bias. In addition, the average (±SD; n = 3) serum neutralization titers of the inactivated RABV and VSV/RABV-GP groups were 241 ± 40 and 103 ± 54 IU/mL, respectivelyConclusionOur results confirm that VSV/RABV-GP could be a new potential vaccination platform for RABV. 相似文献
1000.
Zach Bohannan Raghavendra Sumanth Pudupakam Jamin Koo Harrison Horwitz Josephine Tsang Amanda Polley Enyang James Han Elmer Fernandez Stanley Park Deanna Swartzfager Nicholas Seah Xi Qi Chantal Tu Wendi Velando Rankin Douglas H. Thamm Hye‐Ryeon Lee Sungwon Lim 《Veterinary and comparative oncology》2021,19(1):160-171
We report a precision medicine platform that evaluates the probability of chemotherapy drug efficacy for canine lymphoma by combining ex vivo chemosensitivity and immunophenotyping assays with computational modelling. We isolated live cancer cells from fresh fine needle aspirates of affected lymph nodes and collected post‐treatment clinical responses in 261 canine lymphoma patients scheduled to receive at least 1 of 5 common chemotherapy agents (doxorubicin, vincristine, cyclophosphamide, lomustine and rabacfosadine). We used flow cytometry analysis for immunophenotyping and ex vivo chemosensitivity testing. For each drug, 70% of treated patients were randomly selected to train a random forest model to predict the probability of positive Veterinary Cooperative Oncology Group (VCOG) clinical response based on input variables including antigen expression profiles and treatment sensitivity readouts for each patient's cancer cells. The remaining 30% of patients were used to test model performance. Most models showed a test set ROC‐AUC > 0.65, and all models had overall ROC‐AUC > 0.95. Predicted response scores significantly distinguished (P < .001) positive responses from negative responses in B‐cell and T‐cell disease and newly diagnosed and relapsed patients. Patient groups with predicted response scores >50% showed a statistically significant reduction (log‐rank P < .05) in time to complete response when compared to the groups with scores <50%. The computational models developed in this study enabled the conversion of ex vivo cell‐based chemosensitivity assay results into a predicted probability of in vivo therapeutic efficacy, which may help improve treatment outcomes of individual canine lymphoma patients by providing predictive estimates of positive treatment response. 相似文献