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81.
目的:血管内皮生长因子是一种广泛存在于机体组织的细胞因子,与运动密切相关,是近来运动人体科学界和运动医学界研究的焦点。对近来血管内皮生长因子与运动的相关研究进行综述,以能够找到提高训练质量乃至运动水平的方法。资料来源:应用计算机检索Medscape.net1996-01/2006-12的相关文章,并根据相关的参考文献检索了部分文章,检索词“vascular endothelial growth factor,exercise”,限定语言种类为English;同时计算机检索中国知识资源总库1996-01/2006-12的相关文献,限定语言种类为中文,检索词“血管内皮生长因子,运动”。资料选择:纳入条件:①随机对照试验研究。②试验包括对照组和干预组。同时排除综述和重复的研究。资料提炼:共找到相关研究47篇,排除17篇,30篇符合标准。通过30个实验对运动中血管内皮生长因子在机体中的表达、作用及含量和动态变化进行了相关的分析和研究。资料综合:①血管内皮生长因子与运动的关系密切相关,现在仍然是运动医学界的研究焦点之一,研究的方向为运动对机体血管内皮生长因子的影响,目的是发现运动对机体的影响。②不同的运动方式对机体的血管内皮生长因子的表达不同,目前采用的训练方式多为极限运动或运动与其他因素相结合,如低压强 运动。③观察部位多集中在大脑、肌肉、心血管、血液等,不同部位的表达不同。④运动对血管内皮生长因子表达有动态变化的规律。结论:血管内皮生长因子与运动的关系密切相关,不同的运动方式会造成血管内皮生长因子在机体不同部位不同表达。运动对血管内皮生长因子表达的影响呈现出规律性。  相似文献   
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Background

The long-term survival in hepatocellular carcinoma (HCC) patients with portal vein tumor thrombosis (PVTT) who received surgical resection (SR) or transarterial chemoembolization (TACE) remains unclear. We compared the efficacy of SR and TACE by using a propensity score analysis.

Methods

A total of 247 and 181 HCC patients with PVTT undergoing SR and TACE, respectively, were evaluated. One hundred eight pairs of matched patients were selected from each treatment arm by using a propensity score analysis.

Results

Of all patients, the estimated 1-, 3-, and 5-year survival rates of patients receiving SR and TACE were 85 versus 60 %, 68 versus 42 %, and 61 versus 33 %, respectively (p < 0.001). Patients selected for SR were significantly younger and had better liver functional reserve, performance status, and smaller tumor burden. In the propensity model, the survival benefit of SR remained significant. The estimated 1-, 3-, and 5-year survival rates of patients receiving SR and TACE were 84 versus 71 %, 69 versus 50 %, and 59 versus 35 %, respectively (p = 0.004). The two groups of patients in the propensity score analysis were similar in baseline characteristics. In the Cox proportional hazards model, patients receiving TACE had a 2.044-fold increased risk of mortality compared with patients receiving SR (95 % confidence interval: 1.284–3.252, p = 0.003).

Conclusions

For either unselected patients or patients in the propensity model, SR provides significantly better long-term survival than TACE. SR should be considered as a priority treatment in this subgroup of HCC patients.  相似文献   
84.
The present study aimed to investigate whether facial electromyography (EMG) recordings reflect the perception of effort and primary active lower limb muscle activity during incremental workload cycling. The effects of exercise intensity on EMG activity of the corrugator supercilii (CS), masseter and vastus lateralis (VL) muscles, heart rate (HR) and the rating of perceived exertion (RPE) were investigated, and the correlations among these parameters were determined. Eighteen males and 15 females performed continuous incremental workload cycling exercise until exhaustion. CS, masseter and VL muscle activities were continuously recorded using EMG during exercise. HR was also continuously monitored during the test. During the final 30 s of each stage of cycle ergometer exercise, participants were asked to report their feeling of exertion on the adult OMNI-Cycle RPE. HR and EMG activity of the facial muscles and the primary active lower limb muscle were strongly correlated with RPE; they increased with power output. Furthermore, facial muscle activity increased significantly during high-intensity exercise. Masseter muscle activity was strongly and positively correlated with HR, RPE and VL activity. The present investigation supports the view that facial EMG activity reflects the perception of effort. The jaw clenching facial expression can be considered an important factor for improving the reporting of perceived effort during high-intensity exercise in males and females.

Key points

  • Frowning and jaw clenching muscle activity reflects the perception of effort during incremental workload cycling.
  • EMG activity of the masseter muscle was strongly and positively correlated with RPE, HR and lower limb EMG activity during incremental workload cycling.
  • The jaw clenching facial expression can be considered an important factor for estimating the intensity of effort.
Key words: Perceived exertion, facial electromyography, masseter muscle, corrugator supercilii muscle, incremental exercise testing  相似文献   
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Hepatic arterial pseudoaneurysm is a rare but potentially fatal condition that requires prompt management. We report a case of hepatic arterial pseudoaneurysm developed after radiofrequency ablation of a hepatocellular carcinoma. The patient was successfully treated with percutaneous absolute ethanol injection under ultrasound guidance. Follow-up studies with ultrasound and computed tomography for 2 years after treatment revealed no evidence of local recurrence of hepatocellular carcinoma and of the pseudoaneurysm.  相似文献   
87.
A heat-labile Epstein-Barr virus-specific DNA polymerase stimulatory protein having a molecular mass of 45 kDa was purified from phorbol 12-myristate 13-acetate-treated P3HR-1 cells by column chromatography. The virus DNA polymerase stimulatory protein was precipitated by sera from patients with nasopharyngeal carcinoma but not by sera from healthy donors. The interaction of the stimulatory protein with DNA polymerase was stoichiometric. Furthermore, this protein stimulated Epstein-Barr virus DNA polymerase but not herpes simplex virus type 1 or type 2 or human DNA polymerase alpha. The stimulatory protein did not alter the Km value of dTTP or DNA but did increase the Vmax of DNA polymerase. Salt concentrations between 100 mM and 150 mM KCl were optimal for this protein-induced stimulation of Epstein-Barr virus DNA polymerase activity. The presence of the stimulatory protein in the reaction mixture enhanced the sensitivity of virus DNA polymerase to phosphonoformate.  相似文献   
88.
巨噬细胞迁移抑制因子最初是由于能抑制体外巨噬细胞随机迁移而被发现,现在它作为一种重要的调节因子参与一系列炎症性疾病过程.我们最近发现,巨噬细胞迁移抑制因子的缺失使一些由炎症介质诱发的白细胞-内皮细胞相互作用减弱,提示巨噬细胞迁移抑制因子在炎症反应中起作用的机制之一是促进白细胞聚集.……  相似文献   
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Herpes simplex virus (HSV) encodes a DNA polymerase that is similar in several respects to the replicative mammalian DNA polymerase alpha. Recently, these and other DNA polymerases have been shown to share several regions of protein sequence similarity. Despite these similarities, antiviral drugs that mimic natural polymerase substrates specifically inhibit herpesvirus DNA polymerases. To study amino acids involved in substrate and drug recognition, we have characterized and mapped altered drug sensitivity markers of nine HSV pol mutants and sequenced the relevant portions of these mutants. The mutations were found to occur within four relatively small regions. One such region, which we designate region A, has sequence similarity only to DNA polymerases that are sensitive to certain antiviral drugs. The other three regions contain sequences that are similar among various DNA polymerases. The multiple mutations occurring within two of these regions make it likely that the regions interact directly with drugs and substrates. Our results lead us to favor a model in which protein folding allows interactions among the four regions to form the substrate and drug binding sites.  相似文献   
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