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61.
62.
本文研究指出,Line10肝癌腹水上清具有一定的免疫抑制作用,可致巨噬细胞形态改变并降低其吞噬功能,还可使BALB/c小鼠的白细胞数量下降。应用Ouchterlony法证明Line10肝癌腹水上清中存在line10肝癌细胞的抗原成分。 相似文献
63.
白细胞介素—2新的功能位点及其中枢镇痛作用 总被引:2,自引:0,他引:2
白细胞介素-2(IL-2)不仅是重要的免疫调节因子,而且还具有重要的中枢调节作用。本实验以钾离子透入引起大鼠甩尾反应为指标,发现侧脑室注射IL—2能显著提高动物痛阈,并能被纳洛酮所阻断,表示IL-2的中枢镇痛作用可能与阿片受体有关。利用基因定位突变技术获得的无免疫活性IL-2实查体仍具有中枢镇痛作用,表明IL—2分子上发挥镇痛和免疫调节作用的功能位点是相互独立的。纳洛酮能够阻断IL—2的中枢镇痛作用,而不能影响IL—2增殖CTLL-2细胞的作用,提示IL-2发挥镇痛和免疫调节作用可能通过不同的受体途径。IL-2分子中第45位Tyr残基突变为Val后,虽仍保留了免疫活性,但丧失了镇痛功能,表示45位Tyr残基是IL—2发挥中枢镇痛功能的关键残基之一。我们推测IL—2的镇痛功能位点可能在IL—2分子中第45位Tyr残基附近区域。 相似文献
64.
以辣根过氧化物酶(PO)和抗-PO作为免疫沉淀中的抗原和抗体,用光电比色法,对78例小儿肾脏疾病血清补体对免疫沉淀的抑制作用(IIPC)进行了研究,并同时检测补体成分C3、C4。结果,正常对照IIPCOD值为0.505±0.085,急性肾小球肾炎(0.137±0.108)显著降低(P<0.001);慢性肾小球肾炎(0.470±0.053)改变不明显(P>0.05);肾病综合征(0.401±0.038)明显低下(P<0.05)。IIPC低下的发生率依次为急性肾小球肾炎(83%)、肾病综合征(43%)、慢性肾小球肾炎(32%)。表明小儿肾小球疾病时IIPC大多降低并与疾病的活动性有关。因此认为IIPC低下在肾脏病的发生和发展中起一定作用。 相似文献
65.
34例高血压病患者服国产吲达帕胺后,血压持续缓慢下降,TPR显著下降,血浆肾素活性(RA)、血管紧张素Ⅱ(AT-Ⅱ)和醛固酮(ADS)浓度显著增高,而心率及血儿茶酚爱(CA)水平无显著变化。治疗4周对全轿Cd,Pb,红细胞(RBC)及血浆Zn,Cu,Na,K,Mg浓度无显著影响。其总疗效为88.24%,表明国产吲达帕胺是一种疗效显著而副作用低的降压药物。 相似文献
66.
T.-H. ZHOU X.-H. REN D.-L. YIN Y.-L. WU M. Li C.-Z. Lu D.-C. Wu Y.-Q. Wu Y.-Q. PENG Y.-P. WANG L. MA G. PEI 《Acta anaesthesiologica Scandinavica》1997,41(8):1077-1079
Congenital analgesia is a rare genetic disorder. We report here that a 12-year-old boy was able to recover from congenital insensitivity to pain. Neurological examinations revealed that there was a 'stocking' distribution of pain decrement on the lower extremities under the patient's knee joints. Magnetic Resonance Imaging (MRI) of his brain showed gyrus thinning with sulcus widening at both sides of the parietal lobe. Southern blot hybridization probed with cDNAs of various opioid receptors did not detect any significant abnormality. Our results suggest that this rare case may not be genetically determined. 相似文献
67.
68.
乌贼墨诱生小鼠细胞毒因子活性的检测 总被引:11,自引:2,他引:9
吕昌龙 《中国医科大学学报》1994,23(4):322-323
用乌贼墨处理小鼠后,采集血清。经体外细胞毒实验证明:乌贼墨诱生的血清对人和鼠的肿瘤细胞株均有不同程度的杀伤作用。这一结果提示:乌贼墨可能具有诱生内源性细胞毒因子产生的活性。 相似文献
69.
Several types of chronic pain syndromes are effectively treated with sodium channel blockers such as lignocaine. Further investigation of this therapeutic modality would be facilitated by refinement of the parameters describing lignocaine distribution and elimination. This would allow precise lignocaine infusion by a computer-controlled infusion to attain and maintain stable target lignocaine concentrations. Arterial blood samples were obtained at frequent intervals during a computer-controlled infusion of lignocaine in 12 adult human volunteers. Plasma lignocaine concentrations of 1, 2, 3, 4 and 5 microg/ml were targeted for 15 min at each concentration. A three-compartment mammillary pharmacokinetic model best described the resulting concentration vs time profile. A population pharmacokinetic analysis was performed using three different techniques; the two-stage, pooled and mixed effects modelling. There was marked overshoot of the plasma concentration above the target prior to refinement of the pharmacokinetic parameters. The best parameters of a three-compartment mammillary model fit to the measured concentration using the pooled data approach were: V(1) = 7.44, V(2) =11.5 and V(3) = 97.71; Cl(1) = 0.585, Cl(2) = 2.23 and Cl(3) =1.64 l/min. Similarly calculated parameters using NONMEM were V(1) = 6.99, V(2) =12.2 and V(3) =1341; Cl(1) = 0.703, Cl(2) =1.24 and Cl(3) =1.49 l/min. The addition of age as a covariate of the pharmacokinetic parameters improved the model in both cases. Height, lean body mass and body surface area as covariates of the pharmacokinetic parameters did not improve the predicted value of the model. Prospective testing of the pharmacokinetic parameters will be required to define whether they function well. The refinement of pharmacokinetic parameters for the computer-controlled intravenous infusion of lignocaine will facilitate further research in pain therapy. Published lignocaine pharmacokinetic values have a relatively large central volume of distribution, and hence, when implemented as a computer-controlled infusion, result in dramatic overshoot shortly after targeting a higher plasma concentration. In light of the long-lasting pain relief provided by sodium channel blockade in neuropathic pain states, overshoot of plasma concentrations must be avoided if the concentration vs effect relationship is to be defined. 相似文献
70.
Miguel Cordeiro Pedro Monteiro Dinis Vieira Francisco Parente Nuno Devesa José Moura Luís Providência 《Revista portuguesa de cardiologia》2004,23(3):399-441
Pulmonary embolism (PE) is an important health problem and often a major clinical challenge, not only because of the low specificity of its clinical manifestations but also because of the increasing number of medical circumstances that are risk factors for this illness and the importance of early identification, since prompt and appropriate treatment can decrease mortality from this disease by about 25%. In recent years research on PE has been extensive, directed mainly at trying to determine and characterize its risk factors, establish new clinical probability algorithms, develop new diagnostic methods and put existing ones into perspective, seek new therapeutic approaches (pharmacological and non-pharmacological), and above all establish protocols that can guide the clinician from the stage of clinical suspicion to measures to prevent recurrence. It was the authors' aim to review the most significant literature on this subject, in order to produce a text that reflects the state of the art concerning PE and that can be used as a guide in the clinical approach to this pathology. 相似文献