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排序方式: 共有599条查询结果,搜索用时 22 毫秒
1.
目的探讨生血宁片联合促红细胞生成素和左卡尼汀治疗肾性贫血的临床疗效。方法选取2015年2月—2015年10月成都新华医院肾内科收治的肾性贫血患者94例,随机分为对照组和治疗组,每组各47例。对照组sc重组人促红素注射液(CHO细胞),根据促红细胞生成素使用指南来调整药量;并在透析结束后iv注射用左卡尼汀,1 g加入到生理盐水20m L中。治疗组在对照组基础上口服生血宁片,2片/次,3次/d。两组患者均连续治疗3个月。观察两组患者临床疗效,比较贫血和铁代谢指标及氧化应激水平变化。结果治疗后,对照组和治疗组的总有效率分别为87.23%、97.87%,两组比较差异有统计学意义(P0.05)。治疗后,两组患者的血红蛋白(Hb)、红细胞压积(HCT)、转铁蛋白饱和度(TSAT)及铁蛋白(SF)均明显升高,同组治疗前后差异具有统计学意义(P0.05);且治疗组的这些观察指标改善程度明显优于对照组,两组比较差异具有统计学意义(P0.05)。治疗后,两组患者晚期氧化蛋白产物(AOPP)、丙二醛(MDA)、超氧化物歧化酶(SOD)和谷胱甘肽过氧化物酶(GSH-Px)水平均明显升高,同组治疗前后差异具有统计学意义(P0.05)。治疗后,治疗组AOPP和MDA水平升高幅度低于较对照组,但SOD和GSH-Px水平改善幅度高于对照组,两组比较差异具有统计学意义(P0.05)。结论生血宁片联合促红细胞生成素和左卡尼汀治疗肾性贫血的临床疗效较好,能明显改善贫血和铁代谢,缓解氧化应激反应,具有一定的临床推广应用价值。  相似文献   
2.
IntroductionThe number of solid organ transplants completed annually continues to trend upwards each year. Despite this, maintenance immunosuppression available on the market has remained relatively stagnant. Standard triple immunosuppression, composed typically of tacrolimus, mycophenolate, and steroids, lead to many side effects that limit the use of these medications. Tacrolimus, specifically, causes nephrotoxicity that can lead to renal dysfunction requiring a kidney transplant down the road. Alternative therapies for the management of immunosuppression need to be identified to try to mitigate these adverse effects.BodyCytokines are responsible for facilitating T cell differentiation and lead to the activation of inflammatory mediators that can contribute to graft damage and ultimately rejection. IL-4, IL-6, IL-12/23, and IL-15 are attractive targets for medications to try to ameliorate graft rejection. Various cytokine-targeted medications are currently available on the market for the treatment of inflammatory and autoimmune conditions such as rheumatoid arthritis, psoriatic arthritis, Crohn’s, and multiple sclerosis.ConclusionThis article reviews cytokine involvement in alloimmunity and the potential role cytokine-targeted therapy may play in prevention of allograft rejection in solid organ transplant recipients.  相似文献   
3.
Purpose: The aim of this work is to compare the radiosensitizing effect between organic and inorganic germanium compounds and to investigate whether nanometer-sized germanium particles can act as radiosensitizers.

Materials and methods: Bis (2-carboxyethylgermanium) sesquioxide (Ge-132), germanium oxide (GeO2) and germanium nanoparticles were used in this study. Cell viability was determined by clonogenic survival assay. Cellular DNA damage was evaluated by alkaline comet assay, confocal microscopy and the cellular level of phospho-histone H2AX (γ-H2AX).

Results: Nanometer-sized germanium particles were fabricated. They have a similar radiosensitizing effect as that of GeO2. Conversely, Ge-132 did not enhance the radiosensitivity of cells. Comet assay was employed to evaluate the level of DNA damage and confirmed that inorganic germanium compounds enhanced cellular radiosensitivity. Notably, the comet assay indicated that the nanoparticle itself caused a higher level of DNA damage. The possibility that germanium nanoparticles per se caused DNA damage was ruled out when the cellular level of γ-H2AX was examined.

Conclusions: We demonstrated that inorganic but not organic germanium compounds exerted radiosensitizing effect in cells. Nanometer-sized germanium particles were fabricated and were able to enhance the radiosensitivity of cells. Confounding effect may occur when comet assay is used to estimate the level of DNA damage in the presence of germanium nanoparticles.  相似文献   
4.

Aim:

To examine how the higher expression level of CYP3A4 isoenzyme influenced the cytotoxicity of the antitumor triazoloacridinone derivative C-1305 in Chinese hamster ovary (CHO) cells.

Methods:

Three CHO cell lines were examined: wild-type CHO cells; CHO-HR cells with overexpression of human cytochrome P450 reductase (CPR); and CHO-HR-3A4 cells with coexpression of human CYP3A4 and CPR. Cellular responses caused by C-1305 were monitored using DAPI staining, cell cycle analysis, phosphatydilserine externalization analysis and SA-β-galactosidase expression analysis. Cell viability was assessed with simultaneous FDA and PI staining.

Results:

Treatment with C-1305 for 72 h exhibited different levels of cytotoxicity in the 3 cell lines, and the values of IC80 in CHO, CHO-HR and CHO-HR-3A4 cells were 0.087±0.005, 0.032±0.0001, and 0.064±0.0095 μmol/L, respectively. The cell cycle analysis revealed that both CHO and CHO-HR cells underwent transient G2/M arrest, whereas CHO-HR-3A4 cells did not accumulate in this phase. Prolonged exposure up to 120 h caused time-dependent increase in the sub-G1 fraction in all the 3 cell lines. Treatment with C-1305 caused cell death through apoptosis and necrosis. However, these processes were more pronounced in the transfected CHO cells than in the wild-type cells. The cells surviving after C-1305 exposure underwent senescence.

Conclusion:

CYP3A4 overexpression potently enhances the cellular responses (apoptosis, necrosis and senescence) caused by C-1305 in CHO cells.  相似文献   
5.
目的:从细胞水平探讨LPK-26对κ受体的作用及分子机制。方法:通过[3H]-Dip和[35S]GTPγS放射性结合实验研究LPK-26对CHO细胞上稳定表达κ阿片受体的竞争性受体结合特征及LPK-26对κ阿片受体偶联的G蛋白的激活。结果:LPK-26是一种κ阿片受体激动剂,其Ki值是0.66 nmol.L-1,与U50,488H相似;并且通过[35S]GTPγS结合实验,LPK-26激活G蛋白的能力明显大于U50,488H。结论:LPK-26可能是一种较为理想的新型镇痛药物。  相似文献   
6.
Yang XJ  Lu HY  Li ZY  Bian Q  Qiu LL  Li Z  Liu Q  Li J  Wang X  Wang SL 《Toxicology》2012,300(3):138-148
Cytochrome P450 (CYP) 2A13 is mainly expressed in the respiratory system and has the ability to metabolize aflatoxin B(1) (AFB(1)). However, the role of CYP2A13-mediated AFB(1) metabolism and its consequences in human lung epithelial cell is not clear. Therefore, the objectives of this study were to investigate the significance of CYP2A13 in AFB(1)-induced cytotoxicity, DNA adducts, and apoptosis. To achieve these objectives, CYP2A13 was stably over-expressed in immortalized human bronchial epithelial BEAS-2B cells (B-2A13) and its significance in AFB(1)-induced cytotoxicity, DNA adducts, and apoptosis was compared to cells with stably expression of CYP1A2 (B-1A2), the predominant AFB(1) metabolizing enzyme in liver, as well as CYP2A6 (B-2A6) as controls. AFB(1) induced B-2A13 cytotoxicity and apoptosis in a dose- and time-dependent manner. The cytotoxic and apoptotic effects of AFB(1) were significantly remarkable in B-2A13 cells than those of B-1A2 and B-2A6 cells. The increased expression of pro-apoptotic proteins, such as C-PARP, C-caspase-3, and Bax, and decreased expression of anti-apoptotic proteins, such as caspase-3, Bcl-2, and p-Bad further confirmed the data of AFB(1)-induced cytotoxicity and apoptosis. Furthermore, increased DNA adduct was observed in B-2A13 after AFB(1) treatment as compared to B-1A2 cells and B-2A6 cells. Finally, treatment with nicotine, a competitor of AFB(1), and 8-methoxypsoralen (8-MOP), an inhibitor of CYP enzyme, further confirm the critical role of CYP2A13 in AFB(1)-induced cytotoxicity and apoptosis. Collectively, these findings suggest adverse effects of AFB(1) in respiratory diseases mediated by CYP2A13.  相似文献   
7.
目的比较治疗用皮卡乙型肝炎疫苗(CliO细胞)及疫苗组分(重组乙型肝炎疫苗(CliO细胞)、皮卡佐剂)对小鼠的急性毒性反应。方法ICR小鼠按体重随机分为溶媒对照组,皮卡佐剂高剂量组(原液)和低剂量组(2倍稀释液),重组乙型肝炎疫苗(CHO细胞)组(原液),治疗用皮卡乙型肝炎疫苗(CliO细胞)高剂量组(原液)和低剂量组(2倍稀释液),每组小鼠后肢im0.2mL受试物,给药后连续14天观察其状态及毒性反应。结果各组小鼠全部存活,摄食和体重指标正常,注射部位肌肉、外观体征、行为活动、呼吸、排泄、各组织脏器肉眼观察及组织病理学检查均未见异常。结论在本实验条件下,治疗用皮卡乙型肝炎疫苗(CliO细胞)及疫苗组份对小鼠无明显毒性反应。  相似文献   
8.
Spider venoms are replete with peptidic ion channel modulators, often with novel subtype selectivity, making them a rich source of pharmacological tools and drug leads. In a search for subtype-selective blockers of voltage-gated calcium (CaV) channels, we isolated and characterized a novel 39-residue peptide, ω-TRTX-Cc1a (Cc1a), from the venom of the tarantula Citharischius crawshayi (now Pelinobius muticus). Cc1a is 67% identical to the spider toxin ω-TRTX-Hg1a, an inhibitor of CaV2.3 channels. We assembled Cc1a using a combination of Boc solid-phase peptide synthesis and native chemical ligation. Oxidative folding yielded two stable, slowly interconverting isomers. Cc1a preferentially inhibited Ba2+ currents (IBa) mediated by L-type (CaV1.2 and CaV1.3) CaV channels heterologously expressed in Xenopus oocytes, with half-maximal inhibitory concentration (IC50) values of 825 nM and 2.24 μM, respectively. In rat dorsal root ganglion neurons, Cc1a inhibited IBa mediated by high voltage-activated CaV channels but did not affect low voltage-activated T-type CaV channels. Cc1a exhibited weak activity at NaV1.5 and NaV1.7 voltage-gated sodium (NaV) channels stably expressed in mammalian HEK or CHO cells, respectively. Experiments with modified Cc1a peptides, truncated at the N-terminus (ΔG1–E5) or C-terminus (ΔW35–V39), demonstrated that the N- and C-termini are important for voltage-gated ion channel modulation. We conclude that Cc1a represents a novel pharmacological tool for probing the structure and function of L-type CaV channels.  相似文献   
9.
目的:构建新的具有趋化作用的人类细胞因子PSMP的真核表达载体,在仓鼠卵巢细胞(Chinese hamster ovary,CHO)中表达并纯化,为PSMP的功能机制研究奠定基础.方法:从pcDNA3.1-PSMP-myc/His中切下PSMP-myc/His片段,插入pMH3表达载体.利用电穿孔法将该表达载体转染CHO细胞,G418抗性筛选稳定克隆株.以Dot blot及Western blot法检测上清液中PSMP蛋白的表达,利用有限稀释法对抗性筛选出的混合克隆单克隆化,悬浮无血清大批培养工程细胞,通过镍亲和层析法纯化蛋白,SDS-PAGE电泳分析蛋白纯度,Boyden小室体外趋化实验分析蛋白功能活性.结果:PSMP-myc/His基因插入pMH3载体后成功构建真核表达载体pMH3-PSMP,转染CHO细胞后经2次克隆化获得稳定表达PSMP的基因工程细胞株.镍亲和层析纯化的重组蛋白PSMP纯度达95%以上且具有生物学活性.结论:成功构建了PSMP蛋白的真核表达载体,并获得其稳定表达的CHO细胞株,获得了较高纯度的、具有生物学活性的重组蛋白,为下一步PSMP功能和机制研究提供有用工具.  相似文献   
10.
Magnetic resonance (MR) reporter genes have the potential for tracking the biodistribution and fate of cells in vivo, thus allowing the safety, efficacy and mechanisms of action of cell‐based therapies to be comprehensively assessed. In this study, we evaluate the effectiveness of the iron importer transferrin receptor‐1 (TfR1) as an MR reporter gene in the model cell line CHO‐K1. Overexpression of the TfR1 transgene led to a reduction in the levels of endogenous TfR1 mRNA, but to a 60‐fold increase in total TfR1 protein levels. Although the mRNA levels of ferritin heavy chain‐1 (Fth1) did not change, Fth1 protein levels increased 13‐fold. The concentration of intracellular iron increased significantly, even when cells were cultured in medium that was not supplemented with iron and the amount of iron in the extracellular environment was thus at physiological levels. However, we found that, by supplementing the cell culture medium with ferric citrate, a comparable degree of iron uptake and MR contrast could be achieved in control cells that did not express the TfR1 transgene. Sufficient MR contrast to enable the cells to be detected in vivo following their administration into the midbrain of chick embryos was obtained irrespective of the reporter gene. We conclude that TfR1 is not an effective reporter and that, to track the biodistribution of cells with MR imaging in the short term, it is sufficient to simply culture cells in the presence of ferric citrate. Copyright © 2016 The Authors Contrast Media & Molecular Imaging Published by John Wiley & Sons Ltd.  相似文献   
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