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91.
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93.
Little DM; Farrell JG; Cunningham PM; Hickey DP 《QJM : monthly journal of the Association of Physicians》1997,90(10):641-642
Systemic donor infection is regarded as being an absolute contraindication
to cadaveric organ donation for transplantation. This is largely due to
fear of transmitting pathogenic organisms to the immunosuppressed
recipient. However, due to the current shortage of organs available for
transplantation, clinicians are faced with the option of using organs from
'non-ideal' donors, such as those patients with documented evidence of
infection. We report the successful outcome of six orthotopic liver
transplants, 11 renal transplants, one combined heart lung transplant and
one simultaneous kidney and pancreas transplant with organs from eight
donors in whom bacterial meningitis (n = 7) and acute bacterial
epiglottitis (n = 1) were the antecedent causes of death.
相似文献
94.
B7-1与B7-2对调节人IL-2基因的转录因子NF-κB和AP-1的相同作用 总被引:1,自引:0,他引:1
为了解B7共刺激对细胞因子,特别是对IL-2 mRNA及转录因子NF-κB出和AP-1的影响,探讨B7介导的IL-2调节的分子机制,在异基因混合淋巴细胞反应(MLR)体系中分别或联合加入抗B7-1、抗B7-2单克隆抗体和CTLA-4 Ig以阻断B7/CD28信号传导,通过竞争性PCR定量检测其对IL-2和IL-4 mRNA的影响,并初步测定IFN-γ mRNA的改变,同时用转染MHCⅡ类分子及联合转染等量B7-1或B7-2的NIH3T3转基因细胞tDR7,tDR7/B7-1和tDR7/B7-2刺激CD28+T细胞,通过DNA-蛋白结合实验观察B7对IL-2转录因子NF-出和AP-1的影响.结果表明:抗B7-2单抗和CTLA-4 Ig可明显抑制B7介导的IL-2和IL-4 mRNA合成,而抗B7-1单抗仅有轻度抑制作用,2种或3种抗体联合应用时抑制作用相加.MLR 1-6小时,单独tDR7即可诱导NF-κB的表达,联合转染B7早期对其结合活力无明显影响,6小时后tDR7诱导作用减弱,B7却可显著延长tDR7的诱导作用至72小时.tDR7早期同样可诱导AP-1的表达,联合转染B7分子在24小时内对其有一定的抑制作用,而在反应后期可延长tDR7对AP-1的上调作用,B7-1与B7-2间作用未见明显不同.结论:B7通过减少IL-2 mRNA降解和影响基因转录而上调IL-2分泌,并可同时影响多种细胞因子分泌;在转录水平B7-1与B7-2作用未见明显不同,提示两者的功能差异可能与细胞表达和时间动力学不同有关.详细了解B7介导的T细胞免疫耐受的分子机制有助于设计更好的临床方案预防移植排斥和GVHD. 相似文献
95.
Normal and diseased isolated lungs: high-resolution CT 总被引:8,自引:0,他引:8
96.
97.
M. Arborati D. Benchorba I. Lesieur JG Bizot-Espiard B. Guardiola-Lemaitre MJ Chapman and E. Ninio 《Fundamental & clinical pharmacology》1997,11(1):68-77
Summary— Cholesteryl esters in the hydrophobic core of low-density lipoprotein (LDL) particles constitute a major molecular target during copper-mediated oxidation. To facilitate the rapid analysis and quantitation of the oxidative degradation of LDL cholesteryl esters, we describe a new approach based on light scattering detection following separation by HPLC. We have applied this approach to the evaluation of the protective capacity of a new synthetic antioxidant, S20478, during oxidation of LDL in the presence of copper ions. HPLC separation of cholesterol and the four major molecular species of cholesteryl esters (C16:0, C18:1, C18:2 and C20:4) of LDL was achieved in a single run of 20 min with high sensitivity (50 ng) and low background. Time course studies of the oxidative modification of LDL (ratio LDL protein: copper, 100 μg/mL: 1μM) revealed that the content of unsaturated cholesteryl esters (C20:4 and C18:2) decreased (–30% and –15%, respectively) within 90 min of copper-mediated oxidation, while only minor degradation (up to 15%) of monounsaturated (C18:1) and saturated (C16:0) esters occurred. At 24 hours of oxidation, only traces (< 5%) of the C20:4 and C18:2 esters were detectable; whereas 52% of the C18:1 ester remained (P < 0.01). Of the saturated esters, only minor proportions (35% or less) underwent oxidative modification. In addition, some 81% of free cholesterol was conserved as the native sterol. The synthetic antioxidant, S20478 (50 μM) was capable of inhibiting the initiation and the propagation of copper-mediated LDL oxidation as determined by the time- and dose-dependant inhibition of the formation of conjugated dienes and thiobarbituric acid-reactive substances, as well as the conservation of the net electrical charge of LDL; indeed S20478 conserved cholesteryl esters in their native form up to 24 hours. However, after prolonged exposure to copper ions (48 hours), only 47% of the unsaturated esters remained (C18:2, P < 0.05). Nonetheless, S20478 (10 μM) was more efficient in inhibiting copper-mediated LDL oxidation as compared to probucol at the same concentration. These findings suggest that S20478 may be of potential interest in a new antioxidant approach to therapeutic stabilisation and regression of atherosclerotic plaques. Moreover, this method should prove useful in the assessment of the integrity of native LDL, and provides a new chemical marker of the degree of LDL oxidation. 相似文献
98.
1. Ouabain is known to have natriuretic effects only at high doses, and therefore if endogenously produced ouabain has a role in the regulation of sodium excretion, the renal response to ouabain must be increased substantially in certain physiological situations. The aim of this study is to determine whether treatment with the mineralocorticoid, aldosterone, potentiates that natriuretic response to ouabain. 2. Six conscious sheep received renal arterial infusion of either vehicle or aldosterone (3 μg/h). Forty hours after commencement of infusion ouabain was infused into the renal artery at 400 μg/h for 60min. A second infusion of ouabain was administered on the 6th day of aldosterone treatment. 3. In the absence of aldosterone, the effects on sodium excretion produced by ouabain infusion at 400 μg/h into the renal artery were variable and not statistically significant. Ouabain infusion after 40 h of aldosterone treatment increased sodium excretion from 40 ± 14 to 676 ± 69 μmol/min in the second hour following cessation of ouabain infusion (P< 0.001). Ouabain infusion after 6 days of aldosterone treatment increased sodium excretion similarly. Ouabain-stimulated sodium excretion was significantly greater during aldosterone treatment compared to vehicle treatment (P<0.05). In contrast, no enhancement of effect was observed after acute treatment with aldosterone. 4. These results demonstrate potentiation of the natriuretic response to ouabain infusion by chronic mineralocorticoid treatment and suggest a potential role of endogenous digitalislike factor in the physiological control of sodium homeo stasisaldo sterone, endogenous digitalis-like factor, ouabain, sodium excretion. 相似文献
99.
100.
庆大霉素在小鼠的时辰毒性及时辰药代动力学 总被引:1,自引:0,他引:1
本文研究了庆大霉素对小鼠的毒性及其药代动力学的昼夜节律性变化。雄性ICR小鼠自实验前两周置于标准的明期和暗期下饲养,自由进食进水。毒性实验剂量为庆大霉素290mg/kg,Sc:药代动力学实验剂量为45 mg/kg,Sc。结果表明,庆大霉素毒性及药代动力学因用药时间不同呈明显的昼夜节律性变化。明期中点用药毒性最大,血药浓度最高,AUC值最大:暗期用药毒性小,血药浓度低,AUC值小。提示了庆大霉素毒性的昼夜节律变化与其药代动力学的的昼夜节律变化有密切关系。 相似文献