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71.
Fucosyltransferase IV is an essential enzyme that catalyzes the synthesis of fucosylated oligosaccharides by transferring GDP-fucose to the terminal N-acetylglucosamine with the alpha1,3-linkage. Lewis Y oligosaccharide has a terminal alpha1,3-linked fucose residue and elevation of Lewis Y level is seen in many epithelial cancers. The mechanism of Lewis Y elevation in neoplastic cells is still largely unknown. To study the impact of fucosyltransferase IV on Lewis Y expression and its role on neoplastic cell proliferation, a pEGFP-N1-FUT4 recombinant plasmid was developed and stably transfected into A431 cells. We found that fucosyltransferase IV overexpression promoted cell proliferation and increased the expression of proliferating cell nuclear antigen that correlated with Lewis Y augmentation. Cell cycle analysis demonstrated that fucosyltransferase IV overexpression facilitated cell cycle progression. In conclusion, fucosyltransferase IV overexpression augments Lewis Y expression to trigger neoplastic cell proliferation. These studies suggest that fucosyltransferase IV may serve as a potential therapeutic target for the treatment of Lewis Y-positive epithelial cancers.  相似文献   
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73.
The aim of the study was to investigate the metabolism of 4‐fluoro‐N‐(1‐{2‐[(propan‐2‐yl)phenoxy]ethyl}‐8‐azabicyclo[3.2.1]octan‐3‐yl)‐benzenesulfonamide (PZ‐1150), a novel 5‐HT7 receptor antagonist with antidepressant‐like and anxiolytic properties, by the following three ways: in vitro with microsomes; in vitro employing Cunninghamella echinulata, and in silico using MetaSite. Biotransformation of PZ‐1150 with microsomes resulted in five metabolites, while transformation with C. echinulata afforded two metabolites. In both models, the predominant metabolite occurred due to hydroxylation of benzene ring. In silico data coincide with in vitro experiments, as three MetaSite metabolites matched compounds identified in microsomal samples. In human liver microsomes PZ‐1150 exhibited in vitro half‐life of 64 min, with microsomal intrinsic clearance of 54.1 μL/min/mg and intrinsic clearance of 48.7 mL/min/kg. Therefore, PZ‐1150 is predicted to be a high‐clearance agent. The study demonstrated the applicability of using microsomal model coupled with microbial model to elucidate the metabolic pathways of compounds and comparison with in silico metabolite predictions.  相似文献   
74.
雪豹(Uncia uncia)研究的文献计量评价   总被引:1,自引:0,他引:1  
通过对1950—2010年SCI收录和1989—2010年CSCD收录的雪豹(Uncia uncia)研究文献分析,从年度文献数量变化、国家/地区分布、主要研究机构、期刊分布、发表文献作者、基金资助机构、刊载文献类型、学科类别和语种分布9个方面,对雪豹研究文献的分布规律和研究现状进行了统计分析。结果表明:在SCI上发表雪豹研究论文的国家排名依次是美(50.6%)、英(16.5%)、印度(12.5%)和中国(5.6%);在文献量机构排名方面,国际雪豹基金会和英国爱丁堡大学并列第一,中国科学院排名第五;中国的主要合作国家中包括了美、英和中亚国家(吉尔吉斯斯坦、蒙古)。无论是分布范围还是数量,中国雪豹资源都居于世界第一,而研究却不相匹配,国内在这方面还仍需努力。  相似文献   
75.
目的 利用透明质酸建立小鼠胎肝细胞3D培养体系。 方法 分离获得胚胎12-14天胎肝细胞,利用KM培养基进行初步2D肝干/祖细胞的筛选培养,并利用透明质酸及KM培养基配制水凝胶建立3D细胞培养体系。 结果 胎肝细胞在2D体系中呈现克隆状生长。分离培养获得的肝干/祖细胞克隆在透明质酸建立的3D培养体系保持增殖活性,并进一步获得肝细胞功能特性,表现为3D培养上清中白蛋白合成和尿素水平显著增加。Q-PCR结果显示随着3D培养时间的延长,其肝细胞干性标志如AFP、CK19、EpCAM、Prox1等表达水平都大幅度降低且接近成年小鼠肝脏表达水平。 结论 本研究成功建立基于透明质酸的小鼠胎肝细胞的3D无血清培养体系,并可促进小鼠胎肝细胞肝细胞功能进一步成熟。  相似文献   
76.
Habitat fragmentation has often been implicated in the decline of many species. For habitat specialists and/or sedentary species, loss of habitat can result in population isolation and lead to negative genetic effects. However, factors other than fragmentation can often be important and also need to be considered when assessing the genetic structure of a species. We genotyped individuals from 13 populations of the cooperatively breeding Brown‐headed Nuthatch Sitta pusilla in Florida to test three alternative hypotheses regarding the effects that habitat fragmentation might have on genetic structure. A map of potential habitat developed from recent satellite imagery suggested that Brown‐headed Nuthatch populations in southern Florida occupied smaller and more isolated habitat patches (i.e. were more fragmented) than populations in northern Florida. We also genotyped individuals from a small, isolated Brown‐headed Nuthatch population on Grand Bahama Island. We found that populations associated with more fragmented habitat in southern Florida had lower allelic richness than populations in northern Florida (P = 0.02), although there were no differences in heterozygosity. Although pairwise estimates of FST were low overall, values among southern populations were generally higher than northern populations. Population assignment tests identified K = 3 clusters corresponding to a northern cluster, a southern cluster and a unique population in southeast Florida; using sampling localities as prior information revealed K = 7 clusters, with greater structure only among southern Florida populations. The Bahamas population showed moderate to high differentiation compared with Florida populations. Overall, our results suggest that fragmentation could affect gene flow in Brown‐headed Nuthatch populations and is likely to become more pronounced over time.  相似文献   
77.
78.
张微  田颖  张亚琼  李杰  胡严 《动物学杂志》2024,59(3):349-357
红隼(Falco tinnunculus)被列为国家二级重点保护野生动物,是能同时适应农村和城市环境的小型猛禽,对维持城市生态系统稳定具有重要意义。2022年4月至7月,为在北京救助的7只红隼佩戴了卫星追踪器,追踪其活动轨迹,依据追踪的动物活动位点数据,采用净平方位移-时间曲线依次对各红隼的迁徙模式进行了判别,深入分析了迁徙红隼的迁徙时间、距离和路线等,并采用核心密度法分别计算了迁徙及留居型红隼95%及50%活动区面积。研究结果表明,在北京地区红隼的迁徙模式为部分迁徙,追踪的7只红隼个体(N01 ~ N07)中,4只为留鸟,1只为迁徙鸟,2只居留类型无法准确判断。N01为迁徙红隼,其度夏地和越冬地分别在内蒙古锡林郭勒盟和河北廊坊,此红隼秋季迁徙速度明显高于春季,其春季迁徙距离551 km,历时25 d,平均迁徙速度为22 km/d,而秋季迁徙距离412 km,历时2 d,平均迁徙速度为203 km/d,河北承德滦平县是其春季迁徙的重要中途停歇地。不同红隼个体间95%及50%活动区面积均存在较大差异,迁徙红隼N01 95%、50%活动区面积在度夏区分别为93.10 km2、17.50 km2,在越冬区分别为7.03 km2、0.99 km2;留居型红隼95%、50%活动区面积均值分别为1 165.34 km2、178.71 km2(n = 4),其中最大95%、50%活动区面积分别为4 320.26 km2(N02)、648.22 km2(N02),最小95%、50%活动区面积分别为2.80 km2(N03)、0.29 km2(N03)。本研究揭示了北京地区红隼的迁徙模式、迁徙路线、重要停歇地及活动区状况,为红隼的针对性保护和管理提供了科学依据。  相似文献   
79.
本文报道了寡毛纲(Oligochaeta)巨蚓科(Megascolecidae)腔蚓属(Metaphire)3个新发现物种,分别是象头山腔蚓(M. xiangtoumontis Dong & Jiang sp. nov.),韩摆渡腔蚓(M. hanbaiduensis Dong & Sun sp. nov.)和长白山腔蚓(M. changbaimontis Dong & Shen sp. nov.)。象头山腔蚓受精囊孔2对,位于7/8 ~ 8/9节间,属于M. insulana物种群。韩摆渡腔蚓受精囊孔3对,位于6/7 ~ 8/9节间,属于M. houlleti物种群。长白山腔蚓受精囊孔2对,位于6/7 ~ 7/8节间,属于M. glandularis物种群。所有新物种均附有形态学描述、图片、与相似物种的形态学比较及与GenBank上亲缘关系相近物种的遗传距离计算分析。以上结果丰富了我国腔蚓属蚯蚓的物种多样性,并首次记录了采集于长白山国家级自然保护区的巨蚓科蚯蚓新物种。  相似文献   
80.
Liu HD  Yan Y  Cao XF  Tan PZ  Wen HX  Lv CM  Li XM  Liu GY 《生理学报》2010,62(6):524-528
The aim of the present study is to investigate the expression of a novel estrogen receptor, G protein-coupled receptor 30 (GPR30) and its correlation with matrix metalloproteinases-9 (MMP-9) in epithelial ovarian cancer (EOC). Ovary tissues were obtained from 39 female patients, including 30 cases of EOC and 9 cases of benign ovarian tumor. Four normal ovary tissues were used as control. Immunohistochemical staining was used to detect the expressions of GPR30 and MMP-9. Chi square test, Fisher's exact test and Spearman's rank correlation analysis were used for statistical analysis. The results showed that GPR30 overexpression rate in EOC cases was significantly higher than those in benign ovarian tumor and normal ovary cases. Whereas MMP-9 overexpression rate in EOC cases was significantly higher than that in normal ovary cases, without any difference to that in benign ovarian tumor cases. To demonstrate the relationship between GPR30 and clinicopathological variables of EOC, we further analyzed the pathology type, FIGO stage and age of patients sampled in our study. The analysis showed there were significant differences of GPR30 overexpression rate among various pathology types and different FIGO stages (P<0.05), and no significant difference of both GPR30 and MMP-9 among three age groups (P>0.05). Moreover, GPR30 expression was positively correlated with MMP-9 (r(s)=1.000, P=0.002). These results suggest that GPR30 may be involved in the invasion and metastasis of EOC, being a potential index of EOC early diagnosis and malignancy grade prediction.  相似文献   
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