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1.
目的 :探讨非病毒载体Gen Escort TM II介导质粒骨形态发生蛋白2(p BMP-2)转染对MC3T3-E1细胞增殖和体外成骨分化的影响。方法:以非病毒载体Gen Escort TM II介导报告基因质粒增强型绿色荧光蛋白(p EGFP)转染MC3T3-E1细胞,优化转染条件,荧光显微镜和流式细胞仪评价转染效率。p BMP-2转染MC3T3-E1细胞后,MTT法检测细胞增殖情况,染色法检测碱性磷酸酶(ALP)和茜素红S(ARS)的表达,Real-time PCR分析成骨细胞标志基因ALP、骨涎蛋白(BSP)、Runt相关转录因子2(Runx2)、骨钙素(OCN)和骨桥蛋白(OPN)的表达。结果 :Gen Escort TM II介导p EGFP转染MC3T3-E1细胞后,转染效率达35.02±4.42,MTT结果示基因转染对细胞增殖无影响(P>0.05)。p BMP-2转染组的ALP、ARS表达较p EGFP转染组和未转染组显著,同时Real-time PCR检测结果示,转染后6 d,p EGFP转染组和未转染组相比,p BMP-2转染组的成骨基因ALP、BSP、Runx2、OCN、OPN的表达量差异有显著性意义(P<0.05)。结论:非病毒载体Gen Escort TM II介导BMP-2转染MC3T3-E1细胞可诱导其向成骨方向分化。  相似文献   
2.
Effective gene therapy for cancer remains an elusive goal, even after more than a decade of intensive research. There has been, however, tremendous progress in the development of increasingly sophisticated non-viral (or synthetic) delivery vectors for local and systemic administration of nucleic acids. Recent clinical data has also indicated the feasibility of using antisense oligonucleotides to inhibit inappropriately expressed or mutated genes in human cancers. The purpose of this review is to provide an update of the patent literature on the development of non-viral approaches for cancer gene therapy. In particular, patents on lipoplexes and polyplexes for delivery of therapeutic genes and antisense oligonucleotides are reviewed. The diverse range of antisense strategies being developed and recent clinical data are also highlighted.  相似文献   
3.
目的 以纳米载体聚乙烯亚胺(polyethylenimine,PEI)介导人胰岛素样生长因子1受体(insulin-like growth factor 1 receptor,IGF1R)小干扰(small interfering RNA,siRNA)质粒转染A549肺癌细胞,并初步观察沉默IGF1R基因对A549肺癌细胞体外增殖活性的影响.方法 设计IGF1R小干扰序列,构建PSUPER-IGF1R-siRNA质粒,PEI介导转染A549肺癌细胞,台盼蓝染色法和MTT法测定细胞存活率.结果 测序结果显示构建质粒与基因库IGF1R基因序列一致.PEI介导PSUPER-IGF1R-siRNA质粒转染A549肺癌细胞后,台盼蓝染色法和MTT 法检测结果显示细胞存活率降低,与生理盐水组和pSUPER-EGFR质粒对照组间的差异有统计学意义(P〈0.05).结论 pSUPER-IGF1R-siRNA质粒构建成功,PEI介导其转染A549肺癌细胞后对细胞有生长抑制作用.  相似文献   
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5.

Introduction

The incorporation of quaternary ammonium polyethylenimine (QPEI) nanoparticles into endodontic sealers induces alterations in their structure and surface properties, which may affect the compatibility with the periapical tissues. This work addressed the behavior of human bone cells exposed to extracts from commercial and QPEI containing AH Plus (DeTrey, Konstanz, Germany) and Pulp Canal Sealer EWT (PCS; Kerr Italia Srl, Salerno, Italy).

Methods

Freshly mixed AH Plus and PCS or containing 2% QPEI (0.3 mL spread over the well bottom of a 24-well plate) were extracted with culture medium (1.5 mL for 24 hours at 37°C) and diluted (1:20–1:5000). Osteoblastic or osteoclastic cells were cultured in the presence of QPEI particles (1%–10%) and were exposed to the extracts from unmodified and QPEI containing sealers.

Results

QPEI nanoparticles, at 1% and 2%, did not affect cell behavior. On osteoblastic cells, AH Plus and PCS increased DNA at 1:2500 dilution (levels ≤1:100 were cytotoxic). Alkaline phosphatase activity decreased at dilutions ≤1:500. Comparatively, QPEI containing AH Plus increased DNA at 1:2500 and 1:500 dilutions, and QPEI containing PCS induced ALP activity at 1:2500 and 1:500 dilutions. Regarding osteoclastic cells, DNA increased (AH Plus) or was not affected (PCS) at dilutions up to 1:500 and decreased with more concentrated extracts. Tartrate-resistant acid phosphatase activity decreased with dilutions ≤1:500 for both sealers. QPEI containing sealers presented a similar behavior. The sealers affected some intracellular signaling pathways, and QPEI containing sealers further modulate these mechanisms.

Conclusions

QPEI nanoparticles, at 2%, did not affect cell behavior. However, the incorporation of 2% QPEI particles into AH Plus and PCS modulates the proliferation and differentiation of bone cells, depending on the sealer and the cell type, without increasing the sealers' cytotoxicity.  相似文献   
6.
We summarized the findings of toxicity studies on graphene-based nanomaterials (GNMs) in laboratory mammals. The inhalation of graphene (GP) and graphene oxide (GO) induced only minimal pulmonary toxicity. Bolus airway exposure to GP and GO caused acute and subacute pulmonary inflammation. Large-sized GO (L-GO) was more toxic than small-sized GO (S-GO). Intratracheally administered GP passed through the air-blood barrier into the blood and intravenous GO distributed mainly in the lungs, liver, and spleen. S-GO and L-GO mainly accumulated in the liver and lungs, respectively. Limited information showed the potential behavioral, reproductive, and developmental toxicity and genotoxicity of GNMs. There are indications that oxidative stress and inflammation may be involved in the toxicity of GNMs. The surface reactivity, size, and dispersion status of GNMs play an important role in the induction of toxicity and biodistribution of GNMs. Although this review paper provides initial information on the potential toxicity of GNMs, data are still very limited, especially when taking into account the many different types of GNMs and their potential modifications. To fill the data gap, further studies should be performed using laboratory mammals exposed using the route and dose anticipated for human exposure scenarios.  相似文献   
7.
Polynucleotides are anionic macromolecules which are expected to transfer into the targeted cells through specific uptake mechanisms. So, we developed polynucleotides coating complexes of plasmid DNA (pDNA) and polyethylenimine (PEI) for a secure and efficient gene delivery system and evaluated their usefulness. Polyadenylic acid (polyA), polyuridylic acid (polyU), polycytidylic acid (polyC), and polyguanylic acid (polyG) were examined as the coating materials. pDNA/PEI/polyA, pDNA/PEI/polyU, and pDNA/PEI/polyC complexes formed nanoparticles with a negative surface charge although pDNA/PEI/polyG was aggregated. The pDNA/PEI/polyC complex showed high transgene efficiency in B16-F10 cells although there was little efficiency in pDNA/PEI/polyA and pDNA/PEI/polyU complexes. An inhibition study strongly indicated the specific uptake mechanism of pDNA/PEI/polyC complex. Polynucleotide coating complexes had lower cytotoxicity than pDNA/PEI complex. The pDNA/PEI/polyC complex showed high gene expression selectively in the spleen after intravenous injection into mice. The pDNA/PEI/polyC complex showed no agglutination with erythrocytes and no acute toxicity although these were observed in pDNA/PEI complex. Thus, we developed polynucleotide coating complexes as novel vectors for clinical gene therapy, and the pDNA/PEI/polyC complex as a useful candidate for a gene delivery system.  相似文献   
8.
目的利用流式细胞仪(flow cytometry,FCM)分选获得非染色、同步化的中国仓鼠卵巢(Chinese hamsterovary,CHO)细胞,观察聚乙烯亚胺(polyethylenimine,PEI)在不同周期CHO细胞的瞬时转染和稳定转染效率。方法悬浮培养CHODG44细胞,应用流式细胞仪的光学参数-前向角和侧向角,在细胞主群中设置12个门,然后进行分选。分选出的各门内细胞经碘化丙啶(PI)染色进行细胞周期检测。以PEI为载体分别向含G0/G1、S、G2/M比例较高的细胞亚群和未经分选的细胞转染含绿荧光蛋白(Green Fluorescence Protein,GFP)质粒,利用流式细胞仪检测瞬时转染、稳定转染效率。结果细胞DNA含量与侧向角相关,各细胞亚群G0/G1期细胞所占比例总体上随着侧向角的增大而减小,G2/M细胞所占比例随着侧向角的增大而增多。低侧向角的细胞亚群P2内G0/G1期细胞比例可达80.49%,中侧向角的细胞亚群P7内S期细胞比例可达61.14%,高侧向角的细胞亚群P13内G2/M期细胞比例可达49.88%。转染48h,GFP阳性细胞在G2/M期细胞比例较高的细胞亚群所占比例最高,但瞬时转染效率,S期细胞比例较高的细胞群大于G2/M期细胞比例较高的细胞群。转染2w,稳定转染效率仍为S期细胞比例较高的细胞亚群大于其它细胞亚群及未分选的混合细胞群。结论应用流式细胞仪的光学参数可以有效分选非诱导、无染色分别含有较高比例各周期时相的CHO细胞;PEI的转染效率与转染时细胞所处的细胞周期时相相关,且S期细胞亚群的瞬时和稳定转染效率均高于其它细胞周期亚群。  相似文献   
9.
目的 优化聚乙烯亚胺(polyethylenimine,PEI)介导的细胞转染以提高目的 基因在细胞中的表达强度.方法 根据PEI/DNA不同的质量比(0:1、0.5:1、1:1、2:1、3:1、4:1、5:1、6:1、7:1、8:1、9:1、10:1)利用凝胶阻滞分析结合的情况;不同质量比PEI/DNA形成的复合物对NIH-3T3细胞的转染通过细胞表达强度获得最佳PEb/DNA质量比;比较实验组l(PEI/DNA质量比2:1)、实验组2(重复PEL/DNA质量比2:1)及实验组3(PEI/DNA质茸比4:2)3种转染方案,探讨重复转染的方法是否提高细胞表达强度.结果 ①通过凝胶阻滞分析PEI/DNA能够稳定结合的质量比是1:1~10:1;②PEI/DNA复合物对NIH-3T3细胞进行转染,其荧光表达强度当PEI/DNA(质量比)≤2时随着PEI的增加而提高,当PEI/DNA(质量比)>2时,荧光表达强度反而降低;③采用重复转染的方法实验组2细胞荧光表达强度(24.08±0.28)%明显高于实验组1(8.97±4.02)%和实验组3(14.24±2.68)%(P<0.05).结论 在PEI/DNA(质量比)=2的条件下,PEI/DNA复合物转化NIH-3T3细胞的效果比较理想,重复转染可以提高细胞转染后荧光表达强度.  相似文献   
10.
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