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991.
黄芪多糖硫酸酯的合成及其抗病毒活性研究   总被引:15,自引:0,他引:15  
目的:制备黄芪多糖(PAM)硫酸酯,寻找具有优良抗病毒活性的物质。方法:将纯化得到的PAM,用硫酸化试剂氯磺酸-吡啶合成PAM硫酸酯(PAMS),采用体外抗病毒试验测定了PAMS对I型单纯疱疹病毒HSV-1的活怀。结果:制备了PAMS,在抑制HSV-1活性的试验中给药组与对照组(阿昔洛韦,ACV)之间有非常显著的差异。结论:PAMS有很强的抑制I型单纯疱疹病毒的活性,在相同浓度下,优于ACV。  相似文献   
992.
喘康颗粒抗炎作用研究   总被引:3,自引:0,他引:3  
目的 :研究喘康颗粒抗炎作用 ;方法 :采用二甲苯致小鼠耳廓肿胀、角叉菜胶致小鼠足跖肿胀、蛋清致大鼠足跖肿胀、醋酸致小鼠腹腔毛细血管通透性增加、小鼠棉球肉芽肿 ,对小鼠炎症组织炎症介质丙二醛及肝组织LPO含量的测定 ,进行抗炎作用试验 ,并对结果进行统计学检验 ;结果 :喘康颗粒较显著抑制二甲苯小鼠耳廓肿胀、非常显著抑制角叉菜胶致小鼠足跖肿胀、对蛋清性大鼠足跖肿胀有一定抑制 ,极显著抑制HAC致小鼠腹腔毛细血管通透性增高、显著抑制小鼠棉球肉芽肿。显著降低小鼠炎症组织炎症介质His、PGE、MDA含量 ;结论 :喘康颗粒具有较强的抗炎作用 ,显著降低炎症组织PGE和His含量 ,揭示喘康颗粒抗炎作用是其平喘作用机理之一。  相似文献   
993.
目的:观察颅痛安颗粒对实验动物家兔血液流变学指标的影响。方法:采用全自动血流变快仪(FASCO-303型)观察不同剂量颅痛安颗粒对肾上腺素所致血瘀家兔模型的血液流变学指标的影响。同时设置空白对照组,模型组,正天丸对照组以作对比,并将结果进行统计学检验。结果:颅安颗粒能明显降低血瘀家兔模型的血粘度(高切、中切、低切)、血浆粘度,红细胞压积,血沉、红细胞聚集指数,红细胞电泳时间、卡松屈服应力。结论:颅痛安颗粒能明显改善实验动物家兔的血液流变学指标,药物作用随药物剂量增加而增强。  相似文献   
994.
995.
PURPOSE: Recent advances in the diagnosis and treatment of influenza, such as rapid testing and neuraminidase inhibitor therapy, are available, but their place in clinical practice and their cost-effectiveness have not been determined. MATERIALS AND METHODS: To estimate the cost-effectiveness of these newer interventions, we used a decision model that compared several influenza management strategies: no testing or treatment, amantadine or rimantadine treatment without testing, testing then amantadine or rimantadine treatment, neuraminidase inhibitor treatment without testing, or testing then neuraminidase inhibitor treatment. Antiviral therapy began within 48 hours in febrile patients with characteristic symptoms of influenza. We assumed that antiviral treatment did not change rates of influenza complication or mortality, and chose parameter values in the baseline analysis to bias slightly against antiviral treatment and toward testing strategies. RESULTS: In the baseline analysis, testing strategies are more expensive and less effective than treatment strategies. Amantadine costs $9.06 per illness day avoided or $11.60 per quality-adjusted day gained. Compared with amantadine, zanamivir costs $198 per illness day avoided or $185 per quality-adjusted day gained, whereas oseltamivir costs $252 per illness day avoided or $235 per quality-adjusted day gained. In elderly patients who require reduced dosage, rimantadine costs $128 per quality-adjusted day gained compared with amantadine. In younger patients, amantadine is favored if the likelihood of influenza A is >67%; otherwise, neuraminidase inhibitors are favored. Testing strategies are more costly and less effective when the influenza probability is >30%. No testing or treatment is favored if the influenza probability is <32% and the influenza utility is >0.77. In elderly patients, amantadine is favored over rimantadine if the utility of medication side effects is >0.94. CONCLUSIONS: Antiviral treatment of influenza without rapid testing is reasonable economically in febrile patients with typical symptoms during influenza season. The choice of antiviral agent depends on age, the likelihood of influenza A, and the willingness to pay per quality-adjusted day gained.  相似文献   
996.
目的 :观察胃肠舒泰颗粒对阿托品引起的小鼠胃排空及小肠推进功能抑制作用的影响 ,对正常大鼠血清胃泌素 (GAS)含量的影响。方法 :ICR小鼠 12 0只 ,胃排空实验、小肠推进实验各选 6 0只 ,分别随机分为 6组 ,即阴性对照组、模型对照组、胃肠舒泰颗粒小、中、大剂量组与普瑞博思组 ,以阿托品为抑制剂 ,观察各组胃排空及小肠推进率。SD大鼠 5 0只 ,分 5组 ,观察胃肠舒泰颗粒对大鼠血清 GAS含量的影响。结果 :胃肠舒泰颗粒可促进阿托品抑制的小鼠胃排空率及小肠推进率 ,并可增加正常大鼠血清 GAS的相对含量。结论 :胃肠舒泰颗粒对阿托品引起的小鼠胃排空及小肠推进功能抑制有良好的拮抗作用 ,同时具有升高动物血清 GAS含量的作用 ,这可能是其治疗胃肠动力障碍性疾病的药理学基础。  相似文献   
997.
Despite high anti-HBV efficacies, while the nucleoside analogs (e.g., lamivudine) lead to the emergence of drug-resistance, interferons (e.g., IFN-α causes adverse side-effects. Comparatively, various natural or plant products have shown similar or even better efficacy. Hence, new antiviral strategies must focus not only on synthetic molecules but also on potential natural compounds. In this report, we have combined the in vitro cell culture and in silico molecular docking methods to assess the novel anti-HBV activity and delineate the inhibitory mechanism of selected plant-derived pure compounds of different classes. Of the tested (2.5-50?μg/ml) twelve non-cytotoxic compounds, ten (10?μg/ml) were found to maximally inhibit HBsAg production at day 5. Compared to quercetin (73%), baccatin III (71%), psoralen (67%), embelin (65%), menisdaurin (64%) and azadirachtin (62%) that showed high inhibition of HBeAg synthesis, lupeol (52%), rutin (47%), β-sitosterol (43%) and hesperidin (41%) had moderate efficacies against HBV replication. Further assessment of quercetin in combination with the highly active compounds, enhanced its anti-HBV activity up to 10%. Being the most important drug target, a 3-D structure of HBV polymerase (Pol/RT) was modeled and docked with the active compounds, including lamivudine as standard. Docking of lamivudine indicated strong interaction with the modeled HBV Pol active-site residues that formed stable complex (?G?=??5.2?kcal/mol). Similarly, all the docked antiviral compounds formed very stable complexes with HBV Pol (?G?=??6.1 to ?9.3?kcal/mol). Taken together, our data suggest the anti-HBV potential of the tested natural compounds as novel viral Pol/RT inhibitors.  相似文献   
998.
Chronic hepatitis C infection is a major cause of liver disease and hepatocellular carcinoma worldwide. While hepatitis C has been treated for decades with some success, the introduction of direct acting antiviral agents has revolutionized the treatment of hepatitis C with finite, highly effective, well-tolerated therapy and there are few populations that cannot be successfully treated now or are complicated to manage. The World Health Organization has released elimination targets in an effort to eliminate viral hepatitis and reduce dramatically the morbidity and mortality caused by both viral hepatitis. While hepatitis C is straightforward to treat, it remains problematic to eliminate on a global scale. Diagnosis of hepatitis C remains the major gap in the cascade of care and numerous screening strategies will be required to reduce this gap. While historically, treatment of hepatitis C has been centralized, decentralized approaches will be required to diagnose, evaluate, and link to care the large population of individuals worldwide with hepatitis C across low-, middle-, and high-income countries. With the introduction of multiple pangenotypic treatment options and reduced cost for these therapies, assessment and treatment for those with hepatitis C has been simplified and made more accessible worldwide. There are multiple populations for whom care models are being developed and refined, including those when inject drugs, those who are incarcerated, those who present with sexually transmitted disease including the men who have sex with men population, amongst many others. While a vaccine for hepatitis C remains elusive these efforts continue. Multiple successful elimination efforts have been reported.  相似文献   
999.
Coronaviruses belong to the family Coronaviridae, which primarily cause infection of the upper respiratory and gastrointestinal tract of hosts. Transmissible gastroenteritis virus (TGEV) is an economically significant coronavirus that can cause severe diarrhea in pigs. Silver nanomaterials (Ag NMs) have attracted great interests in recent years due to their excellent anti-microorganism properties. Herein, four representative Ag NMs including spherical Ag nanoparticles (Ag NPs, NM-300), two kinds of silver nanowires (XFJ011) and silver colloids (XFJ04) were selected to study their inhibitory effect on TGEV-induced host cell infection in vitro. Ag NPs were uniformly distributed, with particle sizes less than 20 nm by characterization of environmental scanning electron microscope and transmission electron microscope. Two types of silver nanowires were 60 nm and 400 nm in diameter, respectively. The average diameter of the silver colloids was approximately 10 nm. TGEV infection induced the occurring of apoptosis in swine testicle (ST) cells, down-regulated the expression of Bcl-2, up-regulated the expression of Bax, altered mitochondrial membrane potential, activated p38 MAPK signal pathway, and increased expression of p53 as evidenced by immunofluorescence assays, real-time PCR, flow cytometry and Western blot. Under non-toxic concentrations, Ag NPs and silver nanowires significantly diminished the infectivity of TGEV in ST cells. Moreover, further results showed that Ag NPs and silver nanowires decreased the number of apoptotic cells induced by TGEV through regulating p38/mitochondria-caspase-3 signaling pathway. Our data indicate that Ag NMs are effective in prevention of TGEV-mediated cell infection as a virucidal agent or as an inhibitor of viral entry and the present findings may provide new insights into antiviral therapy of coronaviruses.  相似文献   
1000.
We cloned and sequenced 2C I-IFN, a two-cysteine containing type I interferon (I-IFN) gene, in orange-spotted grouper (Epinephelus coioides). The cDNA has 769 base pairs, the protein has 172 amino acids, and the predicted signal peptide has 18 amino acids with two cysteines. This gene is similar to I-FNs from sea bass and other teleosts. 2C I-IFN has 5 exons and 4 introns, also similar to other teleost I-IFNs. Immunohistochemical (IHC) analysis indicated that expression is predominantly membrane-localized in healthy grouper, but has a zonal distribution in nodavirus-infected grouper. Grouper infected with nodavirus had elevated levels of 2C I-IFN at 72 h and Mx at days 6–7. Recombinant 2C I-IFN activated grouper Mx, leading to upregulated antiviral activity. The grouper Mx promoter was highly induced after treatment with recombinant 2C I-IFN. The present results suggest that expression of grouper 2C I-IFN may participate in the immunologic barrier function against nodavirus.  相似文献   
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