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1.
王锋  张超  郑栓 《中草药》2021,52(24):7473-7483
目的 成功制备雷公藤甲素(3-丙羧基)三苯基溴化膦(TPP)-聚乙二醇-b-聚己内脂(PEG-PCL)脂质体(Tr@TPP/Lip),评价其靶向性及促肝肿瘤细胞凋亡效果。方法 采用正交试验优选Tr@TPP/Lip的制备工艺,再研究该载药系统的粒径、Zeta电位、载药量、包封率和多分散系数及透射电镜微观形态,评价Tr@TPP/Lip的稳定性、溶血性、释放情况;采用荧光试验,研究脂质体与肝肿瘤细胞的融合情况、线粒体靶向性和肝脏靶向性;在等剂量给药条件下,评价Tr@TPP/Lip促肝癌细胞凋亡效果。结果 正交试验优选的Tr@TPP/Lip粒径为(113.5±17.6)nm,Zeta电位(12.6±0.7)mV,包封率为(71.3±3.2)%,载药量为(3.9±1.1)%,多分散系数为0.12±0.04;透射电子显微镜图片显示Tr@TPP/Lip呈规则圆球形,该脂质体稳定性良好,具有较小的溶血率和良好的缓释药物性能;荧光试验结果显示,TPP阳离子能促进脂质体与肿瘤细胞的融合,并靶向线粒体,还能提高药物在肝肿瘤部位的靶向和滞留效果;细胞药效结果显示,Tr@TPP/Lip具有良好的促肝肿瘤细胞凋亡效果,能明显降低线粒体膜Zeta电位、增加细胞内活性氧水平和Caspase-3的释放,显著增加促凋亡蛋白Bcl-2、减少抗凋亡Bax蛋白的表达,这些细胞凋亡试验结果均明显优于雷公藤甲素普通脂质体和雷公藤甲素。结论 Tr@TPP/Lip具有较好的线粒体靶向功能,能增强药物促肝肿瘤细胞凋亡效果。  相似文献   
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目的:探讨抑制半乳糖凝集素3(galectin-3)的表达对人胃癌MGC-803细胞凋亡的影响,为基因靶向治疗提供潜在靶点。方法:人胃癌MGC-803细胞分为siRNA干扰组、空白对照组和阴性对照组,siRNA干扰组MGC-803细胞转染靶向galectin-3的siRNA,空白对照组MGC-803细胞只加转染试剂,阴性对照组MGC-803细胞转染阴性对照的siRNA。采用流式细胞术和碘化丙啶(PI)染色法检测各组细胞凋亡率和细胞凋亡情况,Western blotting法检测各组细胞中galectin-3、Bcl-2和Bax蛋白表达情况。结果:与阴性对照组和空白对照组比较,siRNA干扰组细胞中galectin-3蛋白表达水平明显降低(P<0.05)。PI染色,siRNA干扰组凋亡细胞数量明显增加,凋亡细胞出现细胞核固缩、染色质浓集、新月形和凋亡小体等细胞凋亡特征,阴性对照组仅有少量散在的凋亡细胞。流式细胞术和Western blotting法检测,与阴性对照组和空白对照组比较,siRNA干扰组细胞凋亡率明显升高(P<0.05),Bcl-2蛋白表达水平明显降低(P<0.05),Bax蛋白表达水平未发生明显变化(P>0.05)。结论:抑制galectin-3表达可促进MGC-803细胞的凋亡,提示galectin-3对胃癌细胞发挥癌基因作用,具有成为靶向治疗靶点的可能性。  相似文献   
4.
目的:探讨黄连素对人胃癌细胞SGC7901凋亡的影响。方法:MTS法检测不同浓度的黄连素(100、150、200μmol/L)对胃癌细胞的抑制作用,Hoechst 33258染色检测不同浓度的黄连素(100、150、200μmol/L)对细胞凋亡的影响;Real Time Q-PCR检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的mRNA表达;Western blot检测胃癌细胞中Cleaved Caspase-3、Bcl-2、Bax的蛋白表达。结果:不同浓度的黄连素能显著降低人胃癌细胞SGC701活性(P<0.05,P<0.01),促进其凋亡,升高Cleaved Caspase-3、Bax的mRNA和蛋白表达水平(P<0.05,P<0.01),降低Bcl-2的mRNA和蛋白表达水平(P<0.05,P<0.01)。结论:不同浓度的黄连素可诱导胃癌细胞凋亡,其机制可能与升高Cleaved Caspase-3、Bax的表达,降低Bcl-2的表达有关。  相似文献   
5.
Apoptosis is an important factor during the early stage of intracerebral hemorrhage.MiR-181 c plays a key regulatory role in apoptosis.However,whether miR-181 c is involved in apoptosis of prophase cells after intracerebral hemorrhage remains unclear.Therefore,in vitro and in vivo experiments were conducted to test this hypothesis.In vivo experiments:collagenase type VII was injected into the basal ganglia of adult Sprague-Dawley rats to establish an intracerebral hemorrhage model.MiR-181 c mimic or inhibitor was injected in situ 4 hours after intracerebral hemorrhage.Neurological functional defects(neurological severity scores)were assessed 1,7,and 14 days after model establishment.Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling and western blot assay were conducted 14 days after model establishment.In vitro experiments:PC12 cells were cultured under oxygen-glucose deprivation,and hemins were added to simulate intracerebral hemorrhage in vitro.MiR-181 c mimic or inhibitor was added to regulate miR-181 c expression.3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay,luciferase reporter system,and western blot assay were performed.Experimental results revealed differences in miR-181 c expression in brain tissues of both patients and rats with cerebral hemorrhage.In addition,in vitro experiments found that miR-181 c overexpression could upregulate the Bcl-2/Bax ratio to inhibit apoptosis,while inhibition of miR-181 c expression could reduce the Bcl-2/Bax ratio and aggravate apoptosis of cells.Regulation of apoptosis occurred through the phosphoinositide 3 kinase(PI3 K)/Akt pathway by targeting of phosphatase and tensin homolog deleted on chromosome ten(PTEN).Higher miR-181 c overexpression correlated with lower neurological severity scores,indicating better recovery of neurological function.In conclusion,miR-181 c affects the prognosis of intracerebral hemorrhage by regulating apoptosis,and these effects might be directly mediated and regulated by targeting of the PTEN\PI3 K/Akt pathway and Bcl-2/Bax ratio.Furthermore,these results indicated that miR-181 c played a neuroprotective role in intracerebral hemorrhage by regulating apoptosis of nerve cells,thus providing a potential target for the prevention and treatment of intracerebral hemorrhage.Testing of human serum was authorized by the Ethics Committee of China Medical University(No.2012-38-1)on February 20,2012.The protocol was registered with the Chinese Clinical Trial Registry(Registration No.ChiCTR-COC-17013559).The animal study was approved by the Institutional Animal Care and Use Committee of China Medical University(approval No.2017008)on March 8,2017.  相似文献   
6.
黄海潮  何欣  周捷  聂阳  赵晋  徐单单 《中成药》2020,(5):1163-1168
目的 研究甘木通乙酸乙酯提取物对低糖缺氧诱导神经细胞凋亡的保护作用.方法 PC12细胞结合物理缺氧方式建立缺血性中风的细胞模型,CCK-8检测细胞活性,测定乳酸脱氢酶(LDH)漏出分析细胞膜完整性,流式细胞术和Hoechst 33258染色检测细胞凋亡,JC-1法测定细胞内线粒体膜电位,Western blot检测凋亡相关蛋白Bcl-2、Bax、cleaved caspase-3蛋白表达,检测SOD、MDA水平分析甘木通乙酸乙酯提取物的抗氧化能力.结果 与模型组比较,甘木通乙酸乙酯提取物可以有效提高缺氧PC12细胞的存活率(P<0.01),降低LDH漏出量(P<0.01),提高线粒体膜电位,增加细胞内SOD水平,降低MDA水平,增加Bcl-2蛋白表达,减少Bax,cleaved caspase-3蛋白的表达(P<0.05,P<0.01),降低细胞凋亡率.结论 甘木通乙酸乙酯提取物可抑制低糖缺氧诱导PC12细胞凋亡,该神经保护作用可能与细胞的线粒体凋亡途径有关.  相似文献   
7.
目的探讨富氢生理盐水腹腔注射对家兔脊髓损伤神经细胞凋亡及凋亡相关蛋白表达的影响。方法选用30只雄性家兔,随机分为3组,即健康组、对照组和治疗组,每组10只。对照组采用对生理盐水对脊髓损伤家兔进行治疗,治疗组采用富氢生理盐水治疗对脊髓损伤家兔。采用Allen脊髓重物打击损伤法造模,并对家兔脊髓损伤后后肢行为功能评定。治疗结束后对比健康组、对照组和治疗组脊髓神经细胞凋亡情况,并检测治疗1 d、3 d、6 d、10 d后Bcl-2、Bax和caspase-3蛋白表达情况。结果 Basso分级评分结果显示,家兔脊髓损伤模型造模成功。造模后家兔脊髓神经细胞大量凋亡。与治疗前和对照组相比,给药富氢生理盐水后家兔神经细胞凋亡数明显减少。同时,对照组caspase-3蛋白表达高于健康组(P0.001)和治疗组(P0.001);与健康组相比,治疗组caspase-3蛋白表达水平较高(P0.01)。此外,治疗10 d后,治疗组Bax蛋白表达量低于对照组(t=2.263,P=0.035),但高于健康组(t=1.975,P=0.042);治疗组Bcl-2蛋白表达量高于对照组(t=0.463,P0.05),显著高于健康组(t=2.486,P=0.028);治疗组Bax/Bcl-2蛋白表达低于对照组,差异具有统计学意义(t=2.354,P=0.031)。结论腹腔注射富氢生理盐水显著降低了家兔脊髓损伤神经细胞凋亡及Bax/Bcl-2水平和caspase-3蛋白的表达。  相似文献   
8.
The induction of apoptosis in vivo is a useful tool for investigating the functions and importance of particular tissues. B‐cell leukaemia/lymphoma 2‐associated X protein (Bax) functions as a pro‐apoptotic factor and induces apoptosis in several organisms. The Bax‐mediated apoptotic system is widely conserved from Caenorhabditis elegans to humans. In order to establish a tissue‐specific cell death system in the domestic silkworm, Bombyx mori, we constructed a transgenic silkworm that overexpressed mouse Bax (mBax) in particular tissues by the Gal4‐upstream activation sequence system. We found that the expression of mBax induced specific cell death in the silk gland, fat body and sensory cells. Fragmentation of genomic DNA was observed in the fat body, which expressed mBax, thereby supporting apoptotic cell death in this tissue. Using this system, we also demonstrated that specific cell death in sensory cells attenuated the response to the sex pheromone bombykol. These results show that we successfully established a tissue‐specific cell death system in vivo that enabled specific deficiencies in particular tissues. The inducible cell death system may provide useful means for industrial applications of the silkworm and possible utilization for other species.  相似文献   
9.
Deltamethrin (DLM) is a well‐known pyrethroid insecticide used extensively in pest control. Exposure to DLM has been demonstrated to cause apoptosis in various cells. However, the immunotoxic effects of DLM on mammalian system and its mechanism is still an open question to be explored. To explore these effects, this study has been designed to first observe the interactions of DLM to immune cell receptors and its effects on the immune system. The docking score revealed that DLM has strong binding affinity toward the CD45 and CD28 receptors. In vitro study revealed that DLM induces apoptosis in murine splenocytes in a concentration‐dependent manner. The earliest markers of apoptosis such as enhanced reactive oxygen species and caspase 3 activation are evident as early as 1 h by 25 and 50 µM DLM. Western blot analysis demonstrated that p38 MAP kinase and Bax expression is increased in a concentration‐dependent manner, whereas Bcl 2 expression is significantly reduced after 3 h of DLM treatment. Glutathione depletion has been also observed at 3 and 6 h by 25 and 50 µM concentration of DLM. Flow cytometry results imply that the fraction of hypodiploid cells has gradually increased with all the concentrations of DLM at 18 h. N‐acetyl cysteine effectively reduces the percentage of apoptotic cells, which is increased by DLM. In contrast, buthionine sulfoxamine causes an elevation in the percentage of apoptotic cells. Phenotyping data imply the effect of DLM toxicity in murine splenocytes. In brief, the study demonstrates that DLM causes apoptosis through its interaction with CD45 and CD28 receptors, leading to oxidative stress and activation of the mitochondrial caspase‐dependent pathways which ultimately affects the immune functions. This study provides mechanistic information by which DLM causes toxicity in murine splenocytes. © 2014 Wiley Periodicals, Inc. Environ Toxicol 31: 808–819, 2016.  相似文献   
10.
目的:观察不同压力高压氧(hyperbaric oxygen,HBO)对脑出血(intracerebral hemorrhage,ICH)大鼠出血灶周围组织Bcl-2/Bax比值的影响。方法:应用胶原酶诱导法建立大鼠脑出血模型,将90只雄性脑出血SD大鼠随机分为对照组、高压氧治疗组:1.0ATA组、1.8ATA组、2.0ATA组、2.2ATA组,每组18只,按不同治疗压力于造模后24h进行治疗,1次/d,各组分别于造模成功后第1、3、5天断头取脑,每个时间点各6只。免疫组织化学染色法测定Bcl-2与Bax的表达,对Bcl-2/Bax比值进行统计分析。结果:Bcl-2/Bax比值:第1天时,高压氧治疗组较对照组升高,差异有显著性意义(P0.05),1.8ATA组、2.0ATA组、2.2ATA组较1.0ATA组升高,差异有显著性意义(P0.05),2.2ATA组、2.0ATA组、1.8ATA组依次升高,1.8ATA组、2.0ATA组与2.2ATA组比较差异有显著性意义(P0.05),1.8ATA组与2.0ATA组比较差异无显著性意义(P0.05);第3天时,高压氧治疗组较对照组升高,1.0ATA组与对照组比较差异无显著性意义(P0.05),1.8ATA组、2.0ATA组、2.2ATA组与对照组比较差异有显著性意义(P0.05),2.2ATA组、2.0ATA组、1.8ATA组依次升高,各组之间比较差异均有显著性意义(P0.05);第5天时,高压氧治疗组较对照组升高,差异均有显著性意义(P0.05),2.0ATA组、2.2ATA组低于1.0ATA组,差异无显著性意义(P0.05),1.8ATA组高于1.0ATA组、2.0ATA组、2.2ATA组,差异有显著性意义(P0.05)。结论:HBO治疗可提高出血灶周围脑组织Bcl-2/Bax的比值,抑制出血灶周围组织细胞凋亡,且1.8ATA在提高Bcl-2/Bax的比值上较优。  相似文献   
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