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排序方式: 共有1209条查询结果,搜索用时 23 毫秒
1.
Emerging evidence has shown that the therapy-induced senescent growth arrest in cancer cells is of durable nature whereby a subset of cells can reinstate proliferative capacity. Promising new drugs named senolytics selectively target senescent cells and commit them into apoptosis. Accordingly, senolytics have been proposed as adjuvant cancer treatment to cull senescent tumor cells, and thus, screening for agents that exhibit senolytic properties is highly warranted. Our study aimed to investigate three agents, sorafenib, rapamycin, and venetoclax for their senolytic potential in doxorubicin-induced senescence in HCT116 cells. HCT116 cells were treated with one of the three agents, sorafenib (5 µM), rapamycin (100 nM), or venetoclax (10 µM), in the absence or presence of doxorubicin (1 µM). Senescence was evaluated using microscopy-based and flow cytometry-based Senescence-associated-β-galactosidase staining (SA-β-gal), while apoptosis was assessed using annexin V-FITC/PI, and Muse caspase-3/-7 activity assays. We screened for potential genes through which the three drugs exerted senolytic-like action using the Human Cancer Pathway Finder PCR array. The three agents reduced doxorubicin-induced senescent cell subpopulations and significantly enhanced the apoptotic effect of doxorubicin compared with those treated only with doxorubicin. The senescence genes IGFBP5 and BMI1 and the apoptosis genes CASP7 and CASP9 emerged as candidate genes through which the three drugs exhibited senolytic-like properties. These results suggest that the attenuation of doxorubicin-induced senescence might have shifted HCT116 cells to apoptosis by exposure to the tested pharmacological agents. Our work argues for the use of senolytics to reduce senescence-mediated resistance in tumor cells and to enhance chemotherapy efficacy.  相似文献   
2.
目的研究利用经聚乙烯亚胺(PEI)钝化的荧光碳点(CD)装载阿霉素(DOX)进行药物递送,旨在增加DOX对非小细胞肺癌的治疗作用,减少DOX的心肌毒性。 方法通过一步微波加热法将甘油和PEI的混合物制备成CD-PEI,并通过静电效应将DOX装载至CD-PEI。采用CCK8实验检测CD-PEI-DOX对非小细胞肺癌细胞A549的增殖能力的影响;Transwell实验评估CD-PEI-DOX对A549细胞迁移侵袭能力的影响;最后通过体内动物实验评估CD-PEI-DOX的心肌毒性以及对非小细胞肺癌皮下肿瘤生长的抑制效果。 结果体外细胞实验证实,对比单纯的DOX处理组,CD-PEI-DOX对非小细胞肺癌A549细胞增殖、迁移侵袭能力的抑制作用更为显著。体内实验证实,CD-PEI-DOX纳米复合物治疗组小鼠心肌细胞结构完整,并且能有效抑制小鼠皮下肺癌肿瘤的生长。 结论经PEI钝化的荧光碳点负载阿霉素能显著提高DOX对非小细胞肺癌的治疗效果,并减少DOX对心脏的毒性作用。运用CD-PEI纳米颗粒改善化疗药物递送的治疗方案取得了初步证实,这可为肺癌化学治疗提供新思路,具有广大的临床应用前景。  相似文献   
3.
Bioreducible heparin (HEP)-based nanogels were prepared by derivatizing HEP with vinyl group followed by copolymerizing with cystamine bisacrylamide in aqueous medium in the absence of surfactant. The hydrodynamic diameter of the HEP nanogels could be tuned in the range from 80 to 200 nm. Doxorubicin (DOX) was loaded into the HEP nanogels, and high drug loading content (30%) and efficiency (90%) were achieved. In vitro drug release test revealed that this drug delivery system exhibited strongly redox-sensitive drug release behavior that would greatly favor the in vivo drug delivery performance of the nanogels. After injected into tumor-bearing mice through tail vein, the DOX-loaded HEP nanogels showed remarkable accumulation in tumors as demonstrated by in vivo near infared fluorescence imaging and ex vivo DOX concentration measurements. The doxorubicin accumulation at tumor site goes beyond 9% injected dose per gram of tumor through such delivery system, making that DOX-loaded HEP nanogels have significantly superior in vivo antitumor activity.  相似文献   
4.
BackgroundPeritoneal surfaces are a common site for the dissemination of gastrointestinal and gynecologic malignancy. Often, the surgeon can achieve a complete response. Unfortunately, current perioperative chemotherapy regimens fail to maintain control of cancer nodules within the abdomen and pelvis. More effective perioperative chemotherapy is needed.Materials and methodsThe nanoparticle pegylated liposomal doxorubicin (PLD) was instilled directly into the peritoneal space in peritoneal metastases patients following maximal efforts of cytoreductive surgery to resect abdominal and pelvic disease. Pharmacokinetics were determined intraoperatively during hyperthermic intraperitoneal chemotherapy (HIPEC) conditions and postoperatively during early postoperative intraperitoneal chemotherapy (EPIC) at normothermic conditions.ResultsThe retention of PLD within the peritoneal tissues over a 90-min HIPEC was only approximately 20% and 180 min of HIPEC 40%. The median area under the curve ratio of peritoneal fluid concentration times time as compared to plasma concentration times was over 1000 and increased with dose escalation from 50 to 100 mg/m2. When PLD was instilled for EPIC, the area under the curve ratios were very similar to the HIPEC but retention of drug within the peritoneal tissues with access to cancer nodules was maintained for 24 h with approximately 80% drug utilization. Adverse events were tabulated and found to be absent. No evidence of peritoneal dysfunction from sclerosis was evident with a 1 year of follow-up.ConclusionsThe nanoparticle PLD is slowly absorbed into the intraperitoneal tissues and not appropriate for HIPEC. EPIC is the preferred methodology for administration.  相似文献   
5.
目的 探讨端粒酶和端粒结合蛋白(TRF)在细胞凋亡过程中的作用机制。方法 甲基噻唑四唑法(MTT)检测阿霉素对舌鳞癌Tca8113细胞的抑制作用。通过姬姆萨染色和流式细胞仪观察和检测5mg/L阿霉素诱导凋亡情况;利用酶联免疫吸附实验分析端粒酶活性;采用免疫组化和免疫荧光标记法观察和检测TRF表达及其水平。结果 5mg/L阿霉素处理Tca8113细胞5d和7d后,出现明显凋亡;端粒酶活性降低呈时间依赖性;TRF在细胞核内表达,其表达水平无统计学意义(P〉0.05)。结论 阿霉素诱导Tca8113细胞凋亡可降低端粒酶活性,但不改变TRF表达水平。  相似文献   
6.
《药学学报(英文版)》2023,13(1):425-439
Immunoscenescence plays a key role in the initiation and development of tumors. Furthermore, immunoscenescence also impacts drug delivery and cancer therapeutic efficacy. To reduce the impact of immunosenescence on anti-tumor therapy, this experimental plan aimed to use neutrophils with tumor tropism properties to deliver sialic acid (SA)-modified liposomes into the tumor, kill tumor cells via SA-mediated photochemotherapy, enhance infiltration of neutrophils into the tumor, induce immunogenic death of tumor cells with chemotherapy, enhance infiltration of CD8+ T cells into the tumor-draining lymph nodes and tumors of immunosenescent mice, and achieve SA-mediated photochemotherapy. We found that CD8+ T cell and neutrophil levels in 16-month-old mice were significantly lower than those in 2- and 8-month-old mice; 16-month-old mice exhibited immunosenescence. The anti-tumor efficacy of SA-mediated non-photochemotherapy declined in 16-month-old mice, and tumors recurred after scabbing. SA-mediated photochemotherapy enhanced tumor infiltration by CD8+ T cells and neutrophils, induced crusting and regression of tumors in 8-month-old mice, inhibited metastasis and recurrence of tumors and eliminated the immunosenescence-induced decline in antitumor therapeutic efficacy in 16-month-old mice via the light-heat-chemical-immunity conversion.  相似文献   
7.
目的:研究离子交换型阿霉素载药透明质酸栓塞微球(DHAMs)的制备方法及性能表征。方法:采用油包水(W/O)乳化交联法,以改性透明质酸(HA)为载药基质,通过离子交换原理制备载阿霉素的透明质酸栓塞微球。采用光学显微镜、扫描电子显微镜观察表面形态,考察粒径和溶胀率;采用恒温摇床模拟体内环境初步测定透明质酸微球降解率;采用紫外分光光度法测定DHAMs载药量、包封率和体外释放率;采用傅里叶变换红外光谱(FT-IR)和粉末X射线衍射法(PXRD)对DHAMs进行表征。结果:透明质酸微球形态圆整、表面光滑,平均粒径为(111.83 ± 12.21)μm,溶胀率为201.81%;微球56 d体外降解率为34.31%;微球载药量和包封率分别为(22.09% ± 0.05%)和(99.41% ± 0.21%),且72 h累计释放量可达50%;FT-IR和PXRD分析显示,阿霉素在微球中以无定形形式存在。结论:阿霉素透明质酸微球有较好的载药性能,理化性能良好,具有动脉化疗栓塞的应用前景。  相似文献   
8.
Clinically, the efficacy of chemotherapeutic agents can be dramatically reduced in cancer cells with multiple drug resistance (MDR). In doxorubicin-resistant breast cancer cells, drugs accumulate only within discrete cytosolic organelles that abrogate their therapeutic effects in vitro and in vivo. Photochemical internalization (PCI), a specific branch of photodynamic therapy (PDT), is a novel strategy utilized for the site-specific triggered drug/gene release. The objective of this study was to evaluate the nanoparticle-based PDT/PCI effects on the reversal of drug resistance. Dendrimer phthalocyanine-encapsulated polymeric micelle (DPc/m)-mediated PCI, combined with doxorubicin, was studied in drug-resistant MCF-7 cells and a xenograft model. Our results show that the internalized DPc/m showed unique PCI properties inside the cells and thereby facilitating doxorubicin release from the endo-lysosomes to nuclei after photoirradiation. Moreover, ‘light before’ PCI showed the highest antitumor efficacy and the depth of the proliferating cell nuclear antigen-negative area in tumor sections after DPc/m-mediated PDT was obviously increased by combination therapy with doxorubicin; this indicates the limitation of depth of light penetration in PDT, which may be improved by PCI. We conclude that nanotechnology-based PCI possesses several clinical benefits, such as overcoming drug resistance and treating deeper lesions that are intractable by PDT alone.  相似文献   
9.
The potential of poly(propylene fumarate) (PPF) scaffolds as drug carriers was investigated and the kinetics of the drug release quantified using magnetic resonance imaging (MRI) and optical imaging. Three different MR contrast agents were used for coating PPF scaffolds. Initially, iron oxide (IONP) or manganese oxide nanoparticles (MONP) carrying the anti-cancer drug doxorubicin were absorbed or mixed with the scaffold and their release into solution at physiological conditions was measured with MRI and optical imaging. A slow (hours to days) and functional release of the drug molecules into the surrounding solution was observed. In order to examine the release properties of proteins and polypeptides, protamine sulfate, a chemical exchange saturation transfer (CEST) MR contrast agent, was attached to the scaffold. Protamine sulfate showed a steady release rate for the first 24 h. Due to its biocompatibility, versatile drug-loading capability and constant release rate, the porous PPF scaffold has potential in various biomedical applications, including MR-guided implantation of drug-dispensing materials, development of drug carrying vehicles, and drug delivery for tumor treatment.  相似文献   
10.
DNA is a type of potential biomaterials for drug delivery due to its nanoscale geometry, loading capacity of therapeutics, biocompatibility, and biodegradability. Unfortunately, DNA is easily degraded by DNases in the body circulation and has low intracellular uptake. In the present study, we selected three cationic polymers polyethylenimine (PEI), hexadecyl trimethyl ammonium bromide (CTAB), and low-density lipoprotein (LDL) receptor targeted peptide (RLT), to modify DNA and improve the issues. A potent anti-tumor anthracycline-doxorubicin (DOX) was intercalated into DNA non-covalently and the DOX/DNA was then combined with PEI, CTAB, and RLT, respectively. Compact nanocomplexes were formed by electrostatic interaction and could potentially protect DNA from DNases. More importantly, RLT had the potential to enhance intracellular uptake by LDL receptor mediated endocytosis. In a series of in vitro experiments, RLT complexed DNA enhanced intracellular delivery of DOX, increased tumor cell death and intracellular ROS production, and reduced intracellular elimination of DOX. All results suggested that the easily prepared and targeted RLT/DNA nanocomplexes had great potential to be developed into a formulation for doxorubicin with enhanced anti-tumor activity.  相似文献   
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