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排序方式: 共有289条查询结果,搜索用时 15 毫秒
1.
目的:研究重组杆状病毒(baculovinus)载体介导β—半乳糖苷酶基因(LacZ)对体外培养虹膜色素上皮(IPE)细胞的转染和表达情况。方法:将质粒pCMV—β中的CMV—LacZ表达盒插入杆状病毒表达栽体pFast BacI的Eco RI/Hind Ⅲ位点,构建重组质粒pBac—β,并利用Bac—to—Bac表达系统在Sf9细胞中产生出重组杆状病毒BV—β。将MOI为200的BV—β感染经酶消化加显微法分离培养的IPE细胞,24h后进行X-gal染色。在显微镜下观察IPE中LacZ表达阳性的情况,记录阳性细胞所占的百分比。结果:限制性酶切分析及测序结果表明,我们已成功构建表达质粒pBac—β及重组杆状病毒BV—β。X-gal染色证实杆状病毒介导LacZ在细胞中的表达呈蓝色,弥漫于整个胞浆。感染后24h时表达阳性率达85%。结论:重组杆状病毒可有效介导报告基因在体外培养的IPE细胞中表达,为利用杆状病毒构建可供移植的基因工程化虹膜色素上皮细胞提供了实验依据。 相似文献
2.
Isolation,Replication and Polyhedrin Gene Sequence of an Israeli Helicoverpa Armigera Single Nucleopolyhedrovirus 总被引:1,自引:0,他引:1
A local strain of Helicoverpa armigera baculovirus was isolated from infected H. armigera larvae. Infectivity to Helicoverpa
cells, restriction enzyme analysis and electron microscopy allowed its identification as a single embedded nucleopolyhedrovirus,
designated HaSNPV-IS. Analysis of DNA replication, protein synthesis and polyhedrin expression in HaSNPV-infected cells located
the late and very late phases of the viral cycle at 24 and 48 h after infection, respectively. The viral polyhedrin gene was
isolated and characterized. It encoded for a polypeptide of 246 amino acid residues. A 32 kDa polypeptide was identified by
immunoblot analysis using anti-polyhedrin antiserum. The HaSNPV-IS polyhedrin DNA sequence revealed 99.4% of homology to the
HzSNPV polyhedrin. The availability of this efficient replication system and the above knowledge paves the way to future genetic
engineering of the HaSNPV.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
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Summary Several protocols are presented for preparation and transfection of Baculovirus and plasmid DNAs into Lepidopteran insect cells using the calcium-phosphate co-precipitation technique. Important parameters for optimum efficiency include the inherent susceptibility of the recipient cell line for transfection, and the method of preparation of viral and plasmid DNAs. The protocols presented provide reproducible high efficiencies for transfection of several Lepidopteran cell lines. 相似文献
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Individual specific antigenic rubella virus (RV) structural proteins are required for accurate serological diagnosis of acute and congenital rubella infections as well as rubella immune status. The RV envelope glycoprotein E1 is the major target antigen and plays an important role in viral-specific immune responses. The native virion is difficult to produce in large quantities and the protein subunits are also difficult to isolate without loss of antigenicity. The production of a soluble RV E1 (designated E1ΔTm) using the baculovirus-insect cell expression system is described. In contrast to wild-type RV E1, the genetically engineered E1ΔTm protein lacks a transmembrane anchor. It behaved as a secretory protein and was secreted abundantly from insect cells. Pulse-chase studies were used to examine the synthesis, glycosylation, and secretion of E1ΔTm by the insect cells. The secreted E1ΔTm protein was purified from serum-free medium by onestep immunochromatography. The purified E1ΔTm protein retained full antigenicity and may be a convenient source of E1 protein for use in diagnostic assay and rubella vaccine development. 相似文献
8.
Gaucher disease, the most prevalent sphingolipidosis, is caused by the deficient activity of acid beta-glucosidase, mainly due to mutations in the GBA gene. Over 200 mutations have been identified worldwide, more than 25 of which were in Spanish patients. In order to demonstrate causality for Gaucher disease, some of them: c.662C>T (p.P182L), c.680A>G (p.N188S), c.886C>T (p.R257X), c.1054T>C (p.Y313H), c.1093G>A (p.E326K), c.1289C>T (p.P391L), c.1292A>T (p.N392I), c.1322T>C (p.I402T), and the double mutants [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]) and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]), were expressed in Sf9 cells using a baculovirus expression system. Other well-established Gaucher disease mutations, namely c.1226A>G (p.N370S), c.1342G>C (p.D409H), and c.1448T>C (p.L444P), were also expressed for comparison. The levels of residual acid beta-glucosidase activity of the mutant enzymes produced by the cDNAs carrying alleles c.662C>T (p.P182L), c.886C>T (p.R257X), c.1054T>C (p.Y313H), c.1289C>T (p.P391L), and c.1292A>T (p.N392I) were negligible. The c.1226A>G (p.N370S), c.1322T>C (p.I402T), c.1342G>C (p.D409H), c.1448T>C (p.L444P), and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]) alleles produced enzymes with levels ranging from 6 to 14% of the wild-type. The three remaining alleles, c.680A>G (p.N188S), c.1093G>A (p.E326K), and [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]), showed higher activity (66.6, 42.7, and 23.2%, respectively). Expression studies revealed that the c.1093G>A (p.E326K) change, which was never found alone in a Gaucher disease-causing allele, when found in a double mutant such as [c.680A>G; c.1093G>A] ([p.N188S; p.E326K]) and [c.1448T>C; c.1093G>A] ([p.L444P; p.E326K]), decreases activity compared to the activity found for the other mutation alone. These results suggest that c.1093G>A (p.E326K) should be considered a "modifier variant" rather than a neutral polymorphism, as previously considered. Mutation c.680A>G (p.N188S), which produces a mutant enzyme with the highest level of activity, is probably a very mild mutation or another "modifier variant." 相似文献
9.
乙型肝炎病毒表面抗原(HBsAg)基因重组杆状病毒的构建及鉴定 总被引:1,自引:0,他引:1
目的 利用Bac-to-Bac杆状病毒表达系统,构建乙型肝炎病毒(HBV)表面抗原基因的重组杆状病毒。方法 构建含有HBV S基因的表达截体pFBDHTa—S,转化DH10Bac感受态菌。利用其含有的细菌Tn7转座系统,将该基因重组至杆状病毒穿梭质粒bacmicl中,转染昆虫细胞Sf9,获得含有HBV S基因的重组杆状病毒。结果 构建了的含HBV S基因的重组杆状病毒,感染昆虫细胞后,PCR检测可以扩增出相应大小的片段。结论 利用杆状病毒表达系统,成功地构建了含HBV S基因的重组杆状病毒,为进一步的研究奠定了基础。 相似文献
10.
目的利用昆虫细胞杆状病毒系统表达人的重组可溶性L-型选择蛋白配体凝集素(human recombinant soluble L-selectin:sL-selectin),探索在真核细胞中高效表达人的重组可溶性L-型选择蛋白配体凝集素的新途径。方法将已经重组好的杆状病毒感染昆虫细胞,表达sL-选凝素于细胞培养上清,利用末端连接的ZZ-结构域(蛋白A来源的首尾相连的二聚化Z结构域)与IgG-琼脂糖-6的结合而分离纯化,通过SDS-PAGE鉴定分子量的大小,并用特异性抗体验证,另外通过重组的sL-选凝素与SMMC7721的黏附观察其活性。结果sL-选凝素可在昆虫细胞中表达,产物的分子量约为46000,与人肝癌细胞SMMC7721的结合率可达70%。结论sL-选凝素可通过杆状病毒载体在昆虫细胞中有效表达,分离纯化后依然保持生理活性。 相似文献