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21.
目的探索鲍曼不动杆菌生物膜的形成与耐药的相关性。方法采用96孔板培养法模拟体内生物膜形成,结晶紫染色法鉴定各菌株生物膜生长情况。将鲍曼不动杆菌于黑色聚碳酸酯膜上形成生物膜,其上覆盖药敏纸片,然后将此结构置于涂有大肠埃希菌ATCC25922菌株的M-H平板上,通过测量抑菌圈直径观察生物膜对氯霉素和氧氟沙星的渗透限制作用。结果结晶紫染色测定各菌株均能于体外形成生物膜。除85号菌株外,各菌株与对照组相比,对氯霉素均有明显渗透限制作用,而对氧氟沙星无明显作用。结论生物膜对某些药物的渗透限制作用是细菌耐药的重要机制之一。  相似文献   
22.
DNA甲基化是调节基因表达而不改变DNA碱基序列的表观遗传修饰,通过沉默肿瘤抑制基因在癌症发展中发挥关键作用。DNA去甲基化药物在临床上已经显示出疗效,然而,高效性和特异性的DNA去甲基化药物尚未出现。目前,在市场上已有2种药物阿扎胞苷和地西他滨用于治疗骨髓增生异常综合征。寻找直接结合靶点新的抑制剂是未来的方向。从抗肿瘤活性和临床研究方面介绍了DNA去甲基化药物的研究进展。  相似文献   
23.
任洁  周慧  王晨 《中草药》2019,50(4):808-813
目的研究蒺藜科植物蒺藜Tribulus terrester的干燥成熟果实的化学成分。方法利用硅胶柱色谱、Sephadex LH-20凝胶柱色谱、制备HPLC和薄层色谱等方法进行分离、纯化,并结合HR-ESI-MS与现代波谱学技术鉴定化合物结构。结果从蒺藜果实中分离得到14个化合物,分别鉴定为N-p-阿魏酰酪胺(1)、N-trans-p-coumaroyl-3-O-methyldopamine(2)、甲基阿魏酸(3)、咖啡酸甲酯(4)、原儿茶酸甲酯(5)、trifilines A(6)、5β-spirost-25(27)-en-3β-ol-12-one 3-O-{β-D-glucopyranosyl-(1→2)-O-[β-D-glucopyranosyl-(1→3)]-β-D-glucopyranoside}(7)、tribulosaponin B(8)、isoterrestrosin B(9)、25(R)-螺甾烷-3,5-二烯-12-酮(10)、25(R)-螺甾烷-24β-羟基-4-烯-3,12-酮(11)、26-O-β-D-glucopyranosyl-(25S)-5α-furostane-20(22)-en-12-one-3β,26-diol-3-O-α-L-rhamnopyranosyl-(1→2)-[β-D-glucopyranosyl-(1→4)]-β-D-galactopyranoside(12)、terrestrinone A1(13)和terrestrinone A2(14)。结论化合物1~7为首次从蒺藜科植物中分离得到。  相似文献   
24.
Myocardial perfusion imaging (MPI) is valuable for the diagnosis, prognosis, and management of coronary artery disease (CAD). The most commonly used pharmacologic stress agents at present are vasodilators and adrenergic agents. However, these agents have contraindications and may cause adverse effects in some patients. Thus, other stress agents feasible for more patients are required. Higenamine (HG) is a β-adrenergic receptor agonist currently approved for clinical trials as a stress agent for myocardial infarction. It also has a promising value in MPI for the detection of CAD in preclinical and clinical studies. This review summarizes the application of HG on MPI, including its mechanism of action, stress protocol, efficacy, and safety.  相似文献   
25.
牛连杰  张雅敏 《天津医药》2018,46(7):755-757
无功能胰腺神经内分泌瘤(NF-PNETs)临床罕见,本文回顾性分析天津市第一中心医院 2012 年 7 月— 2017年2月收治的3例病理诊断明确的典型NF-PNETs患者的相关资料,探讨NF-PNETs的临床表现、病理及免疫组 化特点、诊疗及预后情况。  相似文献   
26.
Paraquat (PQ) poisoning, with the lung as a primary target organ, is a devastating disease which irreversibly progresses to diffuse alveolitis followed by extensive lung fibrosis. In the present study, we aimed to investigate the effect of FTY720, an immune modulator, on PQ-induced lung injury in mice. C57BL/6 mice were randomized into four groups: 1) PQ group (n = 12): mice was instilled with PQ (30 mg/kg, ip); 2) PQ + FTY720 group (n = 12): animals received FTY720 (0.1 mg/kg, ip) solution 2 h after PQ exposure and twice a week for 4 consecutive weeks; 3) FTY720 group (n = 5): FTY720 (0.1 mg/kg, ip) was administrated twice a week for 4 consecutive weeks; and 4) Control group (n = 10): same volumes of saline were injected. Mice were sacrificed on either day 3 or day 28 for histopathological, biochemical and immunohistochemical analyses of lung damage indicators. We found that FTY720 treatment attenuated PQ-induced acute lung injury and lung fibrosis as evaluated by histopathological changes and Ashcroft score. On day 3, FTY720 administration reduced PQ-induced increases in lung wet weight/body weight (LW/BW), total protein and cytokine levels including interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in bronchoalceolar lavage fluid (BALF). On day 28, the expressions of alpha-smooth muscle actin (α-SMA), transforming growth factor-beta (TGF-β) and vascular endothelial growth factor (VEGF) detected by immunohistochemistry, as well as the mRNA levels of α-SMA, Type-I Collagen and Type-III Collagen examined by Real-time PCR were down-regulated after FTY720 treatment. These results indicate that FTY720 could attenuate PQ-induced lung injury, but further investigation is necessary.  相似文献   
27.

Purpose

A novel PEGylated and heparinized magnetic iron oxide nano-platform (DNPH) was synthesized for simultaneous magnetic resonance imaging (MRI) and tumor targeting.

Methods

Starch-coated magnetic iron oxide nanoparticles (“D”) were crosslinked, aminated (DN) and then simultaneously PEGylated and heparinized with different feed ratios of PEG and heparin (DNPH1-4). DNPH products were characterized by Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and superconducting quantum interference device (SQUID). The magentic targeting of DNPH3, with appropriate amounts of conjugated PEG and heparin, in a mouse 9L-glioma subcutaneous tumor model was confirmed by magnetic resonance imaging (MRI)/electron spin resonance (ESR).

Results

DNPH3 showed long circulating properties in vivo (half-life >8 h, more than 60-fold longer than that of parent D) and low reticuloendothelial system (RES) recognition in liver and spleen. Protamine, a model cationic protein, was efficiently loaded onto DNPH3 with a maximum loading content of 26.4 μg/mg Fe. Magnetic capture of DNPH3 in tumor site with optimized conditions (I.D. of 12 mg/kg, targeting time of 45 min) was up to 29.42 μg Fe/g tissue (12.26% I.D./g tissue).

Conclusion

DNPH3 showed the potential to be used as a platform for cationic proteins for simultaneous tumor targeting and imaging.  相似文献   
28.
目的探讨中国北方结肠憩室发病趋势的变化。方法选择2011年1月-2015年12月在天津医科大学宝坻临床学院及天津医科大学总医院的消化内镜中心进行肠镜检查的26 463例患者,分析患者年龄、年患病率及年代增长情况。结果共确诊为结肠憩室患者951例(3.59%),其中72.87%为右半结肠憩室,11.88%为左半结肠憩室,15.25%为两侧结肠憩室。憩室的患病率从2011年的2.78%(112/4 028)增长至2015年的4.98%(309/6 208)(P 0.01,趋势分析)。右半结肠憩室好发年龄60岁,左半结肠憩室好发年龄≥60岁。男性和年龄增长均是发生结肠憩室的独立危险因素。结论随着人口老龄化、生活方式的西方化及城市工业化,中国北方的憩室患病率正在逐步增加。  相似文献   
29.

Purpose

To evaluate the effectiveness comparing the combination of TACE with local ablative therapy and monotherapy on the treatment of HCC using meta-analytical techniques.

Methods

Randomized controlled trials and clinical studies comparing TACE plus local ablative therapy with monotherapy for HCC were included in this meta-analysis. Response rate, 1-, 2-, 3-, and 5-year survival rate, and overall survival (OS) were analyzed and compared.

Results

Eighteen studies included a total of 2,120 patients with HCC 1,071 and 1,049 patients for treatment with combination therapy and monotherapy, respectively. The combination therapy group had a significantly better survival in terms of 1-, 2-, 3-, and 5-year survival rate (RR 1.10, 95 % CI 1.03–1.18, P = 0.005; RR 1.20, 95 % CI 1.10–1.30, P < 0.0001; RR 1.43, 95 % CI 1.18–1.73, P < 0.0001; RR 1.40, 95 % CI 1.22–1.61, P < 0.0001, respectively), OS (HR 0.66, 95 % CI 0.51–0.85, P = 0.001), and response rate (RR 1.54, 95 % CI 1.09–2.18, P = 0.013) than that monotherapy group in patients with HCC.

Conclusions

The meta-analysis indicates that the combination of TACE with local ablative therapy was superior to monotherapy in the treatment for patients with HCC.  相似文献   
30.
目的 优化羧甲基壳聚糖/氧化海藻酸钠(CMCS/OSA)复合水凝胶制备工艺,并应用于软骨组织工程。方法 制备氨基与醛基比例分别为2:1、1:1、1:2的CMCS/OSA复合水凝胶,并通过扫描电子显微镜观察、流变学检测、黏附拉力测试、溶胀率分析及细胞实验等方法评价复合水凝胶的微观形态、物理特性以及生物相容性,以制备满足软骨再生领域需求的水凝胶。结果 氨基与醛基比为1:1时,制备出的水凝胶具有良好的孔隙率、适宜的成胶时间、较强的黏附力及稳定的溶胀率等性质,对细胞有良好的生物相容性。结论 氨基与醛基比为1:1时制备出的CMCS/OSA复合水凝胶是软骨组织工程优异的支架材料。  相似文献   
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