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91.
Aim: To investigate the effect of balsalazine treatment on intestinal mucosal permeability in dextran sulfate sodium (DSS)-induced colitis and to determine the mechanism of the balsalazine-induced changes.
Methods: Experimental colitis was induced in C57BL/6J mice by the administration of 5% DSS. Balsalazine was administered intragastrically at doses of 42, 141, and 423 mg/kg. The disease activity index (DAI) score was evaluated and colon tissue was collected for the assessment of histological changes. The amount of malondialdehyde (MDA) in the colon was determined, along with the activity of myeloperoxidase (MPO), superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px). Mucosa from the small intestine was collected to determine the levels of tumor necrosis factor (TNF)-α and interferon (IFN)-γ. The mucosa was ultrastructurally examined with transmission electron microscopy and intestinal permeability was assayed using Evans blue.
Results: Balsalazine was found to reduce the DAI score and the histological index (HI) score, decrease the MDA content and the activity of MPO, and increase the activity of SOD and GSH-Px in colitis mice. At the same time, balsalazine ameliorated microvillus and tight junction structure, resulting in a decrease in the amount of Evans blue permeating into the intestinal wall and the levels of TNF-α and IFN-γ in colitis mice.
Conclusion: In colitis mice, the anti-colitis effect of balsalazine results in a decrease in intestinal mucosal permeability. The mechanism of this effect is partly associated with balsalazine's antioxidative and anti-inflammatory effects.  相似文献   
92.
Delta-atracotoxins (delta-ACTX), isolated from the venom of Australian funnel-web spiders, are responsible for the potentially lethal envenomation syndrome seen following funnel-web spider envenomation. They are 42-residue polypeptides with four disulfides and an "inhibitor cystine-knot" motif with structural but not sequence homology to a variety of other spider and marine snail toxins. Delta-atracotoxins induce spontaneous repetitive firing and prolongation of action potentials resulting in neurotransmitter release from somatic and autonomic nerve endings. This results from a slowing of voltage-gated sodium channel inactivation and a hyperpolarizing shift of the voltage-dependence of activation. This action is due to voltage-dependent binding to neurotoxin receptor site-3 in a similar, but not identical, fashion to scorpion alpha-toxins and sea anemone toxins. Unlike other site-3 neurotoxins, however, delta-ACTX bind with high affinity to both cockroach and mammalian sodium channels but low affinity to locust sodium channels. At present the pharmacophore of delta-ACTX is unknown but is believed to involve a number of basic residues distributed in a topologically similar manner to scorpion alpha-toxins and sea anemone toxins despite distinctly different protein scaffolds. As such, delta-ACTX provide us with specific tools with which to study sodium channel structure and function and determinants for phyla- and tissue-specific actions of neurotoxins interacting with site-3.  相似文献   
93.
丹参和透明质酸钠注射液对骨性关节炎治疗作用的实验研究   总被引:22,自引:0,他引:22  
采取家兔膝关节制动方法建立骨性关节炎动物模型,用丹参注射液和透明质酸钠注射液关节腔内注射进行治疗,分别在制动后3、6、9周测量关节活动度,取关节软骨制成标本经光镜和透射电镜观察。结果显示,与单纯制动组比较,丹参治疗组和透明质酸钠治疗组的关节活动度明显改善,关节病变出现晚,程度轻,以早期最明显。表明丹参和透明质酸钠具有延缓和减轻关节退变的作用,对骨性关节炎早期有一定的治疗作用。  相似文献   
94.
低分子肝素联合奥扎格雷钠治疗急性脑梗死疗效评价   总被引:4,自引:2,他引:4  
目的评价低分子肝素联合奥扎格雷钠治疗急性脑梗死的有效性及安全性。方法将96例符合诊断标准的急性脑梗死患者随机分成3组,每组32例,分别给予低分子肝素联合奥扎格雷钠(联合组)治疗,并与单纯应用低分子肝素(低分子肝素组)和单纯应用奥扎格雷钠(奥扎格雷钠组)治疗的患者进行临床疗效、治疗前后神经功能缺损程度评分(NDS)的比较。结果治疗后联合组显效率(75%)明显优于低分子肝素组(31.3%)及奥扎格雷钠组(34.4%),NDS减分程度与低分子肝素组及奥扎格雷钠组相比,差异均有统计学意义(P<0.05,P<0.01)。结论低分子肝素联合奥扎格雷钠治疗急性脑梗死疗效显著并且安全可靠。  相似文献   
95.
An efficient method for the quantitative determination of acetaminophen (AAP) and diclofenac sodium (DS) in commercial suppositories based on partial least squares (PLS) treatment of FT‐Raman spectra is described. The relative standard errors of prediction (RSEP) were calculated for calibration and validation data sets to evaluate the quality of the constructed models. In the case of DS determination, RSEP error values of 1.9 % and 2.3 % for the calibration and validation data sets, respectively, were found. For AAP these errors amounted to 1.6–2.3 % and 1.8–2.8 %, respectively, for the different calibration models. Four commercial preparations containing 5, 12.5, 16.7 and 33.3 % (w/w) AAP and one containing 5 % (w/w) DS were successfully quantified using the developed models. Concentrations derived from the developed models correlated strongly with the declared values and yielded recoveries of 99.4–100.2 % and 99.6 % for AAP and DS, respectively. The proposed procedure can be used as a fast, economic and reliable method for quantification of the active pharmaceutical ingredients in suppositories. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
96.
The aim of this ex vivo study was to evaluate the infiltration capability and rate of microleakage of a low-viscous resin infiltrant combined with a flowable composite resin (RI/CR) when used with deproteinised and etched occlusal subsurface lesions (International Caries Detection and Assessment System code 2). This combined treatment procedure was compared with the exclusive use of flowable composite resin (CR) for fissure sealing. Twenty premolars and 20 molars revealing non-cavitated occlusal carious lesions were randomly divided into two groups and were meticulously cleaned and deproteinised using NaOCl (2%). After etching with HCl (15%), 10 premolar and 10 molar lesions were infiltrated (Icon/DMG; rhodamine B isothiocyanate (RITC)-labelled) followed by fissure sealing (G-?nial Flo/GC; experimental group, RI/CR). In the control group (CR), the carious fissures were only sealed. Specimens were cut perpendicular to the occlusal surface and through the area of the highest demineralisation (DIAGNOdent pen, KaVo). Using confocal laser-scanning microscopy, the specimens were assessed with regard to the percentage of caries infiltration, marginal adaption and internal integrity. Within the CR group, the carious lesions were not infiltrated. Both premolar (57.9%± 23.1%) and molar lesions (35.3%± 22.1%) of the RI/CR group were uniformly infiltrated to a substantial extent, albeit with significant differences (P=0.034). Moreover, microleakage (n=1) and the occurrence of voids (n=2) were reduced in the RI/CR group compared with the CR group (5 and 17 specimens, respectively). The RI/CR approach increases the initial quality of fissure sealing and is recommended for the clinical control of occlusal caries.  相似文献   
97.
目的 探讨高氧对新生大鼠肺泡Ⅱ型上皮(alveolar epithelial typeⅡ,ATⅡ)细胞钠转运功能的影响.方法 分离提取新生大鼠ATⅡ细胞,随机分成高氧组和对照组,分别在氧浓度为85%和21%的细胞培养箱中原代培养.应用Western blot方法和全细胞膜片钳技术检测高氧暴露后上皮钠通道(epithelial sodium channel,ENaC)蛋白表达变化及高氧对阿米洛利敏感性钠电流的影响.结果 高氧使新生大鼠ATⅡ细胞中β-ENaC和γ-ENaC表达增加[β-ENaC:(1 d:0.43±0.06 vs0.32 ±0.04,P=0.047;2 d:0.73 ±0.06 vs 0.50±0.08,P=0.019;3 d:0.72±0.08 vs 0.52±0.06,P=0.027);γ-ENaC:(1 d:0.64 ±0.05 vs 0.53 ±0.05,P =0.044;2 d:0.76 ±0.03 vs 0.52 ±0.04,P =0.001;3 d:0.77±0.06 vs 0.61 ±0.05,P=0.025)],同时使阿米洛利敏感性钠电流增强(1 d:13.71±2.77 vs 8.92±1.38,P<0.001;2 d:29.12±11.03 vs 10.41±1.80,P<0.001),面对α-ENaC表达表现出一定的抑制作用(1 d:0.31 ±0.05 vs 0.46 ±0.05,P =0.025;2 d:0.30 ±0.01 vs 0.38 ±0.02,P =0.002;3 d:0.37 ±0.06vs 0.37 ±0.08,P=0.983).结论 高氧促进了 ATⅡ细胞ENaC钠转运功能,ENaC功能障碍并非高氧暴露后肺水肿发生的主要原因.  相似文献   
98.
99.
鱼腥草抗炎药理作用机制的研究进展   总被引:1,自引:0,他引:1  
鱼腥草为传统的清热解毒中药,临床应用多年,被卫生部列为药食两用、极具开发潜力的资源。药理研究表明,鱼腥草在炎症性疾病方面表现出较好的疗效。综述国内外关于鱼腥草抗炎的药理作用机制的研究进展,并分析了今后研究的方向和思路,为研究与开发以鱼腥草为原料的抗炎新药提供参考。  相似文献   
100.
Terminalia arjuna has been marked as a potential cardioprotective agent since vedic period. The present study was aimed to investigate the effects of butanolic fraction of Terminalia arjuna bark (TA-05) on Doxorubicin (Dox)-induced cardiotoxicity. Male wistar rats were used as in vivo model for the study. TA-05 was administered orally to Wistar rats at different doses (0.42 mg/kg, 0.85 mg/kg, 1.7 mg/kg, 3.4 mg/kg and 6.8 mg/kg) for 6 days/week for 4 weeks. Thereafter, all the animals except saline and TA-05-treated controls were administered 20 mg/kg Dox intraperitonially. There was a significant decrease in myocardial superoxide dismutase (38.94%) and reduced glutathione (23.84%) in animals treated with Dox. Concurrently marked increase in serum creatine kinase-MB (CKMB) activity (48.11%) as well as increase in extent of lipid peroxidation (2.55-fold) was reported. Co-treatment of TA-05 and Dox resulted in an increase in the cardiac antioxidant enzymes, decrease in serum CKMB levels and reduction in lipid peroxidation as compared to Dox-treated animals. Electron microscopic studies in Dox-treated animals revealed mitochondrial swelling, Z-band disarray, focal dilatation of smooth endoplasmic reticulum (SER) and lipid inclusions, whereas the concurrent administration of TA-05 led to a lesser degree of Dox-induced histological alterations. These findings suggest that butanolic fraction of Terminalia arjuna bark has protective effects against Dox-induced cardiotoxicity and may have potential as a cardioprotective agent.  相似文献   
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