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151.
用PCR法从正常中国人脐带血提取总DNA作为模板,扩增出1.5 kb的人G-CSF基因组基因。序列分析证实其正确性。将其插入小鼠乳清酸蛋白(WAP)基因的起始密码子ATG前的KpnⅠ位点,使其受控于2.6kb的WAP调控序列,构建成乳腺表达载体pWGG。回收经EcoRⅠ酶切后的8.7kb片段用于显微注射。共注射1200枚受精卵,移植34受体母鼠,产仔鼠85只。经PCR检测和DNA印迹分析,证实获得两只整合有人G-CSF基因的雄性鼠,整合率为2.37%。建立的转基因鼠系表明,采用ELASA方法对F1代雌鼠乳汁检测,成功地表达出人G-CSF。表达量为120~250ng/ml。这一结果表明转基因的表达具有乳腺特异性。这为在大动物中实施转基因提供了依据。 相似文献
152.
Relational diversity can be characterized by heterogeneous distributions of tie strengths in social networks and this diversity is present not only among humans, but throughout the animal world. We account for this observation by analyzing two network datasets from Facebook. We measure the strength of a tie by calculating the extent of overlap of friends between the two individuals. Based on the previous findings in human experiments, we argue that it is very unlikely that players will allocate their investments equally to their neighbors. There is a tendency that players prefer to donate more to their intimate friends. We find that if players preferentially allocate their investments to their good friends, cooperation will be promoted in PDG. We proved that the facilitation of the cooperative strategy relies mostly on the cooperative allies between best friends, resulting in the formation of cooperative clusters which are able to prevail against the defectors even when there is a large cost to cooperate. Moreover, we discover that the effect of relational diversity cannot be analyzed by adopting classical complex networks models, because neither of the artificial networks is able to produce networks with diverse distributions of tie strengths. It is of vital importance to introduce real social networks to study the influence of diverse relations especially when it comes to humans. This research proposes a brand new perspective to understand the influence of social relations on the emergence of cooperation in evolutionary prisoner’s dilemma games. 相似文献
153.
Li Wang Yun Xiao Yanyan Ping Jing Li Hongying Zhao Feng Li Jing Hu Hongyi Zhang Yulan Deng Jiawei Tian Xia Li 《PloS one》2014,9(8)
Cross-talk among abnormal pathways widely occurs in human cancer and generally leads to insensitivity to cancer treatment. Moreover, alterations in the abnormal pathways are not limited to single molecular level. Therefore, we proposed a strategy that integrates a large number of biological sources at multiple levels for systematic identification of cross-talk among risk pathways in cancer by random walk on protein interaction network. We applied the method to multi-Omics breast cancer data from The Cancer Genome Atlas (TCGA), including somatic mutation, DNA copy number, DNA methylation and gene expression profiles. We identified close cross-talk among many known cancer-related pathways with complex change patterns. Furthermore, we identified key genes (linkers) bridging these cross-talks and showed that these genes carried out consistent biological functions with the linked cross-talking pathways. Through identification of leader genes in each pathway, the architecture of cross-talking pathways was built. Notably, we observed that linkers cooperated with leaders to form the fundamentation of cross-talk of pathways which play core roles in deterioration of breast cancer. As an example, we observed that KRAS showed a direct connection to numerous cancer-related pathways, such as MAPK signaling pathway, suggesting that it may be a central communication hub. In summary, we offer an effective way to characterize complex cross-talk among disease pathways, which can be applied to other diseases and provide useful information for the treatment of cancer. 相似文献
154.
E.Devol在1945年发表的《Ferns and Fern Allies of EastCentral China》一书131页上记载了Pyrrosia hastata(Thunb.)Ching[现已作为P.tricuspis(Sw.)Tagawa的异名],并称是为我国的首次记录。 相似文献
155.
156.
[目的]本文从胜利油田沾3区块的高温油藏的原油采出液中分离得到一株嗜热菌,通过其与膨润土的相互作用,尝试探讨油藏微生物作为油藏储层中水敏性矿物(如蒙皂石)改性剂的可能性。[意义]研究结果将在降低水敏矿物的膨胀性能,为解决水驱采油中遇到的水敏效应的瓶颈问题提供微生物的新途径。[结果]所得菌株为革兰氏阳性菌,呈杆状,具芽孢,兼性厌氧,鉴定为Geobacillus icigianus SL-1。菌株SL-1在厌氧条件下能够还原蒙皂石的结构铁。扫描电镜(SEM)结果显示,无菌对照体系中,蒙皂石呈不规则薄片状。而经微生物作用后,除薄片状蒙皂石外,另有板状次生矿物的生成。进一步能谱(EDS)分析表明,与薄片状蒙皂石相比,板状矿物含有较高的Al/Si比值,且含有明显的K+信号。XRD结果显示,经过微生物作用后,固相物质中蒙皂石的百分比下降至47.7%,伊利石百分比上升至29.1%,而无菌对照组中蒙皂石的百分含量则为70.4%,伊利石的百分比则为19.8%。XRD物相分析和EDS结果均证实经过微生物作用后,部分蒙皂石转化成了伊利石。膨胀性能的分析进一步揭示菌株SL-1作用后,矿物膨胀性较初始矿物显著降低,缩膨率达到25.9%。以上结果为油藏储层防膨提供了重要的实验依据。 相似文献
157.
Gupta Prachi Zhang Peng Sheriff Jawaad Bluestein Danny Deng Yuefan 《Biomechanics and modeling in mechanobiology》2021,20(3):1013-1030
Biomechanics and Modeling in Mechanobiology - We developed a multiscale model for simulating aggregation of multiple, free-flowing platelets in low–intermediate shear viscous flow, in which... 相似文献
158.
Li Jiang-Fan He Lei Deng Yong-Qiang Qi Shu-Hui Chen Yue-Hong Zhang Xiao-Lu Hu Shi-Xiong Fan Rui-Wen Zhao Guang-Yu Qin Cheng-Feng 《中国病毒学》2021,36(6):1484-1491
Virologica Sinica - The sudden emergence of severe acute respiratory syndrome coronavirus (SARS-CoV) has caused global panic in 2003, and the risk of SARS-CoV outbreak still exists. However, no... 相似文献
159.
为了研究鸡FOXL2基因的结构和功能,本研究克隆了广西麻鸡FOXL2基因编码区序列,分析了其突变位点及与其他物种的同源性和进化距离,以及在高产组和低产组母鸡卵巢组织中的表达水平.结果 表明:广西麻鸡FOXL2基因的编码区长度为918 bp,共编码305个氨基酸,存在一处错义突变和两处同义突变.通过物种间的同源性分析显示,广西麻鸡FOXL2基因与原鸡(Gallus gallus)、雉鸡(Phasianus colchicus)、绿头鸭(Anas platyrhynchos)、野鸽(Columba livia)、人(Homo sapiens)、小鼠(Mus musculus)的同源性分别为99.7%、98.8%、95.1%、92.0%、75.7%、75.5%.通过种间进化树分析表明,广西麻鸡与原鸡(Gallus gallus)的亲缘关系最近,与小鼠(Mus musculus)的亲缘关系最远.FOXL2在高低产蛋量鸡卵巢中的表达水平结果显示:FOXL2基因在高产蛋组中的表达量显著高于低产蛋组中的表达量(P<0.05).该研究结果提示鸡FOXL2的序列相对较保守,对卵巢功能的维持和提高产蛋量具有功能性作用. 相似文献
160.
Xia Meng Ruiying Sun Wei Wang Na Zhang Shiguang Cao Boxuan Liu Ping Fang Shanshan Deng Shuanying Yang 《Journal of cellular and molecular medicine》2021,25(2):827-839
Previously, we identified differentially expressed proteins, including ADFP, between lung adenocarcinoma (LAC) tissue and paired normal bronchioloalveolar epithelium. In this study, we investigated the role of ADFP in LAC. ADFP levels in the serum of patients with lung cancer and benign diseases were measured by enzyme-linked immunosorbent assays (ELISA). shRNA was used to knock-down or overexpress ADFP in A549 and NCI-H1299 cells. The biological function of ADFP and its underlying mechanisms was evaluated in vivo and in vitro. ADFP was highly expressed in the serum of lung cancer patients, especially those with LAC. ADFP promoted cell proliferation and up-regulated the p-Akt/Akt ratio in A549 and NCI-H1299 cells in vitro. Furthermore, in nude mice, ADFP promoted tumour formation with high levels of p-Akt/Akt, Ki67 and proliferating cell nuclear antigen (PCNA). Similar to the effect of ADFP knock-down, MK-2206 (a phosphorylation inhibitor of Akt) reduced A549 and NCI-H1299 cell proliferation. In ADFP-overexpressing A549 and NCI-H1299 cells, proliferation was suppressed by MK-2206 and returned to the control level. ADFP did not regulate invasion, migration or adhesion in LAC cells. Together, these results suggest that ADFP promotes LAC cell proliferation in vitro and in vivo by increasing Akt phosphorylation level. 相似文献