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41.
低剂量他克莫司治疗大鼠急性脊髓损伤的实验研究 总被引:2,自引:1,他引:1
目的:探讨低剂量他克莫司(tacrolimus,又名FK506)对大鼠急性脊髓损伤是否具有神经保护作用。方法:雄性Wistar大鼠72只,随机分为假手术组(12只)、损伤组(30只)和FK506治疗组(30只)。采用Allen’s打击法致伤大鼠T10脊髓,假手术组仅做椎板切除术。FK506治疗组在脊髓损伤后5min一次性经尾静脉注射FK5060.3mg/kg,其余两组以相同方法给予等量生理盐水。致伤后30min、6h、24h、48h、72h取伤段脊髓组织行病理观察及原位末端标记法(TUNEL)检测神经细胞凋亡,伤后1、3、7、14、21d行脊髓功能BBB评分和斜板实验。结果:伤后3、7、14、21d,FK506治疗组斜板实验和BBB评分明显优于损伤组,两组间比较差异有显著性(P〈0.05);伤后各时间点FK506治疗组脊髓损伤区出血坏死较损伤组轻;伤后6、24、48、72h神经细胞凋亡FK506治疗组较损伤组明显减少,两组间比较差异有显著性(P〈0.05)。结论:在大鼠急性脊髓损伤后早期应用低剂量他克莫司(0.3mg/kg)治疗对神经具有保护作用,可减少神经细胞凋亡,减轻脊髓继发性损伤,促进脊髓功能恢复。 相似文献
42.
Controversial issues in the treatment of hyperkalaemia. 总被引:2,自引:2,他引:0
43.
A. C. T. Huizinga R. H. G. Vandenbrom J. M. K. H. Wierda M.D. Ph.D. F. D. M. Hommes P. J. Hennis 《Acta anaesthesiologica Scandinavica》1992,36(5):463-468
The intubating conditions and neuromuscular blocking profile following 600 micrograms.kg-1 rocuronium (Org 9426) have been investigated in patients under various experimental conditions. They were compared with conditions following 1.5 mg.kg-1 suxamethonium, preceded by a precurarising dose (10 mg) of gallamine, and with those in a control group in the absence of a muscle relaxant. Rocuronium produced good to excellent intubating conditions at 60 as well as at 90 s after administration, even though there was only a partial blockade of the adductor pollicis muscle. Intubating conditions following suxamethonium were comparable with those after rocuronium. Half of the control patients could be intubated. The clinical duration and the recovery time of 600 micrograms.kg-1 of rocuronium were 24(4) and 9(3) min (mean(s.d.)), respectively. Rocuronium may have a major advantage over existing non-depolarising muscle relaxants due to the early presence of excellent intubating conditions. The results indicate that rocuronium may replace suxamethonium in procedures in which rapid sequence induction is required. 相似文献
44.
Martin Ungerer Michael Böhm Robert H. G. Schwinger Erland Erdmann 《Naunyn-Schmiedeberg's archives of pharmacology》1990,341(6):577-585
Summary The effects of the new inotropic agents saterinone, sulmazole, UD-CG 212.C1 and milrinone at A1 adenosine receptors and m-cholinoceptors were evaluated in human myocardium from patients with heart failure. At A1 adenosine receptors, all compounds inhibited 3H-DPCPX-binding to ventricular membrane preparations at micromolar concentrations. As judged from the Ki-values, the rank order of potency was saterinone > sulmazole > UD-CG 212.C1 > milrinone. The new inotropic agents also displaced the binding of 3H-QNB at m-cholinoceptors. Except for saterinone, the concentration ranges of mean Ki-values were considerably higher at m-cholinoceptors than at A1 adenosine receptors. The rank order of potency was saterinone > sulmazole > UD-CG 212.Cl > milrinone. Competition of the A1 adenosine receptor agonist R-PIA to 3H-DPCPX-binding showed a biphasic curve with a shallow slope (Hill coefficient nH = 0.63) and revealed two affinity states of the A1 adenosine receptor. In the presence of guanine nucleotides [Gpp(NH)p], the competition curve showed one low affinity class of binding sites and was shifted to the right. In contrast, the competition curves of the new inotropic agents were characterized by a monophasic, steeper slope (mean Hill coefficient nH = 0.98). Guanine nucleotides had no effect. Similar results were obtained with saterinone and carbachol at m-cholinoceptors. Competition with carbachol revealed three affinity states of the m-cholinoceptor, the superhigh affinity binding was reversed by Gpp(NH)p. Competition with saterinone revealed one class of binding sites which was not influenced by Gpp(NH)p. Accordingly, in isolated, electrically driven human atrial trabeculae, the negative inotropic effect of adenosine was antagonized concentration-dependently by saterinone, sulmazole and UD-CG 212.Cl. Similarly the negative inotropic effect of carbachol was antagonized concentration-dependently by saterinone. It is concluded that the new inotropic agents bind to A1 adenosine receptors and that their interaction is of antagonist nature. This mechanism might contribute to their capacity to enhance force of contraction by stimulation of cAMP-formation in addition to phosphodiesterase inhibition. The effects of saterinone may be partially due to antagonism at m-cholinoceptors. This is presumably not the case with the other inotropic agents studied given their low affinity for this receptor.Send offprint requests to M. Böhm at the above addressSupported by the Deutsche Forschungsgemeinschaft 相似文献
45.
46.
系统地研究了肟类药物对塔崩抑制的大鼠脑AChE的体外重活化作用,并与梭曼、沙林和VX进行了比较。结果表明,沙林和VX抑制的AChE较易被药物重活化,而塔崩和梭曼抑制的AChE则较难。37℃、pH7.2条件下,塔崩抑制的大鼠脑AChE可浓度依赖性地被TMB_r和LuH_6重活化,2-PAM在高浓度下也有一定作用,但HI-6在所用3个浓度下均无重活化。通过降低抑制温度成功地建立了未老化的梭曼膦酰化AChE模型。药物试验表明,未老化的梭曼膦酰化大鼠脑AChE可被高浓度(1mmol/L)HI-6重活化,而不被2-PAM、TMB_4及LuH_6重活化。提示药物自身内在活性在重活化作用中的重要性。TMB_4和LuH_6对塔崩磷酸化AChE有较强重活化,而对未老化梭曼膦酸化AChE无重活化,HI-6则相反,对未老化梭曼膦酰化AChE重活化效果好,而对塔崩磷酰化AChE无重活化作用。塔崩和梭曼膦酰化AChE在未老化以前对药物的响应就有所不同,毒剂残基的空间效应可能起重要作用。 相似文献
47.
以中药验方胃久灵对大白鼠的两种急性溃疡模型、一种慢性溃疡模型及两种胃炎模型用药治疗,证明胃久灵确有抗溃疡抗胃炎作用.其中对慢性溃疡的治疗作用较为突出.经急、慢性毒性实验,未见对重要脏器有任何毒性损害. 相似文献
48.
N. D. Edwards MB BS FRCAnaes M. Hartley MB P. Clyburn MB BS FRCAnaes M. Harmer MB BS FRCAnaes 《Anaesthesia》1992,47(5):435-437
A double-blind randomised study was performed to assess the value of the addition of pethidine 50 mg to the initial dose of bupivacaine given for epidural analgesia in labour. Forty-nine patients received either 1 ml of saline (n = 24), or 50 mg of pethidine (n = 25), added to 9 ml of 0.25% bupivacaine as an initial injection for intrapartum epidural analgesia. There was a significant increase in the mean duration of analgesia in the pethidine group. However, pethidine did not increase the speed of onset of analgesia, or improve the quality of analgesia. 相似文献
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50.
本文报道用杂交瘤技术建立了2株分泌抗人精浆蛋白单克隆抗体的细胞株D1和C12。D1株分泌的抗体为IgM,C12株为IgG3。这两株均能与正常人精浆和无精子症患者的精浆产生特异性免疫反应。D1株单抗具有补体依赖性制动人精子的作用,间接免疫荧光试验表明,它能结合到人精子颈部和顶体后区。这充分说明2株单抗是特异性抗人精浆的,D1是精子制动抗体,其相应的精子抗原属于精子外套抗原成分之一。 相似文献