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71.
山东省不同植被区内野生植物根围AM菌的生态分布 总被引:22,自引:2,他引:22
AM菌是土壤习居菌 ,生态适应性强 ,可发生在各种生态环境。寄主范围也十分广泛 ,除少量植物如莎草科、苋科、灯心草科、藜科、石竹科等 2 0余科植物不能或不易形成AM外 ,大多数植物包括苔藓、蕨类、裸子植物、被子植物都能被菌根菌侵染。当前人们十分重视对野生植物上AM菌的调查[3 ,4 ,1 0 ,1 1 ,1 4 ]。研究发现 ,野生植物上可能有比栽培作物更多的AM菌种类[1 ]。我国野生植物资源丰富 ,开发和利用野生寄主植物上的AM菌潜力巨大。由于AM菌对寄主植物的选择性及对环境条件的适应性不同 ,或进化过程中的历史原因 ,造成了自然生态… 相似文献
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Type II collagen is a major protein that maintains biological and mechanical characteristics in articular cartilage. Focal adhesion kinase (FAK) is known to play a central role in integrin signaling of cell–extracellular matrix (ECM) interactions, and chondrocyte–type II collagen interactions are very important for cartilage homeostasis. In this study, we focused on phosphorylation of FAK and MAP kinase in chondrocyte–type II collagen interaction and dedifferentiation, and the effects of FAK knockdown on chondrocyte‐specific gene expression and cell proliferation were determined. The addition of exogenous type II collagen to chondrocytes increased levels of tyrosine phosphorylation, p‐FAKY397, and p‐ERK1/2. In contrast, expression levels of p‐FAKY397 and p‐ERK1/2, but not p‐Smad2/3, were decreased in dedifferentiated chondrocytes with loss of type II collagen expression. Type II collagen expression was significantly increased when dedifferentiated chondrocytes were transferred to alginate beads with TGF‐β1 or type II collagen, but transfected cells with small interfering RNA for FAK (FAK‐siRNA) inhibited mRNA expression of type II collagen and SOX‐6 compared to the control. These FAK‐siRNA‐transfected cells could not recover type II collagen even in the presence of TGF‐β1 or type II collagen in alginate beads culture. We also found that FAK‐siRNA‐transfected cells decreased cell proliferation rate, but there was no effect on glycosaminoglycans (GAGs) secretion. We suggest that FAK is essentially required in chondrocyte communication with type II collagen by regulating type II collagen expression and cell proliferation. J. Cell. Physiol. 218: 623–630, 2009. © 2008 Wiley‐Liss, Inc. 相似文献
74.
Angioarrestin是一种具有潜在应用价值的肿瘤血管形成抑制因子.利用DNA重组法构建了angioarrestin C端 hFD cDNA 和麦芽糖结合蛋白(MBP)重组原核表达质粒 pMAL-C2-hFD.将重组质粒转入大肠杆菌E.coli BL21(DE3),经0.3 mmol/LIPTG 在37℃条件下诱导表达4h,SDS-PAGE 检测,融合蛋白表达量约占细菌总蛋白的20%.Western印迹证实,目的蛋白N端带有MBP标签.取表达上清纯化、透析、浓缩并冻干,以此为抗原免疫Balb/c小鼠制备多克隆抗体.此多抗可以与pET 22b(+)表达系统获得的 hFD重组蛋白发生良好的抗原抗体反应,ELISA检测多抗效价达1∶10240.实验证明:通过基因重组可获得angioarrestin C端hFD在大肠杆菌中的高效表达蛋白,且该蛋白具有较高的免疫活性.以此为抗原制备的抗angioarrestin多克隆抗体为深入研究angioarrestin提供了材料. 相似文献
75.
四个鲫鱼品系线粒体DNA的限制性酶切分析 总被引:10,自引:0,他引:10
用差速离心和核酸酶消化法从红鲫 (C auratusredvar .)、湘鲫 [F1hybridsofredcruciancarp (♀ )×commoncarp (♂ ) ]、野鲫 (C auratusauratus)和白鲫 (C auratuscuvieri)的肝组织及白鲫的卵巢中提取和纯化线粒体DNA。用 9种内切酶 (EcoRⅠ、HindⅢ、PstⅠ、BglⅡ、BamHⅠ、XhoⅠ、XbaⅠ、SalⅠ和KpnⅠ )进行单酶酶解 ,经琼脂糖凝胶电泳分析 ,检测出PstⅠ、KpnⅠ和BglⅡ 3种酶在品系间存在限制性片段长度多态性 ,但并未检测出品系内的限制性片段长度多态性。计算出红鲫、湘鲫、白鲫和野鲫的mtDNA大小分别约为 16 19、 16 0 2、 16 6 0和 16 0 6kb。根据限制性酶切片段共享度 ,计算出 4个品系间的遗传距离 ,结果表明存在直接亲缘关系的红鲫与湘鲫之间的遗传差异最小 ,证实了红鲫与子代湘鲫之间mtDNA遵循母系遗传的特性。 相似文献
76.
Wenqiao He Yuhan Gao Yuqi Wen Xuemei Ke Zejin Ou Jiaqi Fu Mingji Cheng Yun Mo Qing Chen 《中国病毒学》2022,37(2):215-222
Bocaviruses are associated with many human infectious diseases, such as respiratory tract infections, gastroenteritis, and hepatitis. Rats are known to be reservoirs of bocaviruses, including rodent bocavirus and rat bocavirus. Recently, ungulate bocaparvovirus 4, a known porcine bocavirus, has also been found in rats. Thus, investigating bocaviruses in rats is important for determining the origin of the viruses and preventing and controlling their transmission. To the best of our knowledge, no study to date has investigated bocaviruses in the livers of rats. In this report, a total of 624 rats were trapped in southern China between 2014 and 2017. Liver and serum samples from rats were tested for the prevalence of bocaviruses using PCR. Sequences related to ungulate bocaparvovirus 4 and rodent bocavirus were detected in both liver and serum samples. Interestingly, the prevalence of ungulate bocaparvovirus 4 (reference strain:KJ622366.1) was higher than that of rodent bocavirus (reference strain:KY927868.1) in both liver (2.24% and 0.64%, respectively) and serum samples (2.19% and 0.44%, respectively). The NS1 regions of ungulate bocaparvovirus 4 and rodent bocavirus related sequences displayed over 84% and 88% identity at the nucleic acid and amino acid levels, respectively. Furthermore, these sequences had similar genomic structure, genomic features, and codon usage bias, and shared a common ancestor. These viruses also displayed greater adaptability to rats than pigs. Our results suggested that ungulate bocaparvovirus 4 and rodent bocavirus may originate from rats and may be different genotypes of the same bocavirus species. 相似文献
77.
Lei Yang Lingqian Tian Leshan Li Qiuhong Liu Xiang Guo Yuan Zhou Rongjuan Pei Xinwen Chen Yun Wang 《中国病毒学》2022,37(3):341-347
Transformation-associated recombination (TAR) has been widely used to assemble large DNA constructs. One of the significant obstacles hindering assembly efficiency is the presence of error-prone DNA repair pathways in yeast, which results in vector backbone recircularization or illegitimate recombination products. To increase TAR assembly efficiency, we prepared a dual-selective TAR vector, pGFCS, by adding a PADH1-URA3 cassette to a previously described yeast-bacteria shuttle vector, pGF, harboring a PHIS3-HIS3 cassette as a positive selection marker. This new cassette works as a negative selection marker to ensure that yeast harboring a recircularized vector cannot propagate in the presence of 5-fluoroorotic acid. To prevent pGFCS bearing ura3 from recombining with endogenous ura3-52 in the yeast genome, a highly transformable Saccharomyces cerevisiae strain, VL6-48B, was prepared by chromosomal substitution of ura3-52 with a transgene conferring resistance to blasticidin. A 55-kb genomic fragment of monkeypox virus encompassing primary detection targets for quantitative PCR was assembled by TAR using pGFCS in VL6-48B. The pGFCS-mediated TAR assembly showed a zero rate of vector recircularization and an average correct assembly yield of 79% indicating that the dual-selection strategy provides an efficient approach to optimizing TAR assembly. 相似文献
78.
一百余年前,人类就开始了相对系统的野生动物调查。目前已经建立了成熟的方法体系,并制定了相应的调查规范。最近几十年来,我国科研人员进行了大量的野生动物调查。但是,当前我国的野外调查规范还不够细致,调查者在调查时缺乏必要的约束,导致调查数据不规范、不可靠,很多重要信息缺失。突出问题有:样线信息不全,只有起点和终点的经纬度,没有自动记录的详细样线信息(如每秒记录一次的连续点位信息,含经纬度和时间);动物位点信息缺乏可信度指标(如距观测者的距离);调查时间不合理;调查地点的空间取样不均衡;记录的标准化不够(如每个观测点的观测时长不确定)等等。对此,我们参考国际通用的调查规范,提出了一些简单易行的调查要点,以便提高野外调查数据的质量。另外,我们提倡野外记录的无纸化,充分利用现有的手机应用软件(APP)和模型工具提高野外记录以及后期数据处理的效率。最后,我们提议建立固定的中国生物多样性监测样线体系,以便消除每年调查时空间取样的不确定性,更好地量化野生动物的时间动态,为野生动物的保护和管理提供依据。 相似文献
79.
对我国11个双子叶植物(Dicotyledon)原白中模式标本引证的排印错误做了更正:砚山锥栗(壳斗科)原白中错误地将模式标本引证为王启无84116,实际应为王启无84416,前者属于菊科植物Inuna helianthus-aquatica C.Y.Wu ex Ling。长果柯(壳斗科)原白中错误地将模式标本引证为K.M.Feng 13012,实际应为K.M.Feng 13102,前者属于冬青科植物Ilex triflora Bl.。福建红小麻(荨麻科)原白中错误地将主模式标本引证为C.J.Chen&Z.Y.Li 109,实际应为C.J.Chen&Z.Y.Li 103,前者属于荨麻科植物Oreocnide frutescens(Thunb.)Miq.。少毛全缘叶紫麻(荨麻科)原白中错误地将主模式标本引证为N.K.Chun 44099,实际应为N.K.Chun 44033,前者属于杜鹃花科植物Lyonia ovalifolia(Wallich)Drude var.rubrovenia(Merr.)Judd.。甘南铁线莲(毛茛科)原白中错误地将主模式标本引证为Baishuijiang Exped.4490,实际应为Baishuijiang Exped.4990,前者属于卫矛科植物Euonymus alatus(Thunb.)Sieb.。矮粗距翠雀花(毛茛科)原白中错误地将模式标本引证为Sichuan Veg.Exped.3137,实际应为Sichuan Veg.Exped.3173,前者属于龙胆科植物Gentiana conduplicata T.N.Ho。镇康黄芪(豆科)原白中错误地将主模式标本引证为T.T.Yu 17255,实际应为T.T.Yu 17225,前者属于莎草科植物Scirpus lushanensis Ohwi。宽翼棘豆(豆科)原白中错误地将模式标本引证为Qinghai-Xizang Comp.Exped.9484,实际应为Qinghai-Xizang Comp.Exped.9485,前者属于石竹科植物Arenaria kansuensis Maxim.。肾瓣黄芪(豆科)原白中错误地将模式标本引证为Qinghai-Xizang Comp.Exped.3650,实际应为Qinghai-Xizang Comp.Exped.3605,前者属于麻黄科植物Ephedra gerardiana Wall.ex Mey.。湖南长柄槭(槭树科)原白中错误地将模式标本引证为李泽棠2944,实际应为李泽棠2994,前者属于杜鹃花科植物Pieris formosa D.Don。峨眉勾儿茶(鼠李科)原白中错误地将模式标本引证为杨光辉54729,实际应为杨光辉54723,前者属于山茱萸科植物Helwingia chinensis Batalin.。 相似文献
80.