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31.
J.Martinez Calatayud C.Gomez Benito D.Gaspar Gimenez 《Journal of pharmaceutical and biomedical analysis》1990,8(8-12):667-670
A flow injection-fluorimetric determination of thiamine is reported. The procedure is based on the oxidation of the analyte with potassium hexacyanoferrate(III) immobilized on an anionic exchange resin; the fluorescence is monitored in aqueous basic solution. Concentrations of the vitamin of 0.1–4 ppm have been determined; the relative standard deviation was 1.8%. The injection rate was 28 samples/h. The influence of other substances and the determination of the drug in a pharmaceutical formulation are also reported. 相似文献
32.
采用高效液相色谱法测定了异丙酚在不同温度下及其甲醇 水(V∶V=70∶30)混合溶液在不同pH值下的反应速率常数,并求出了异丙酚氧化反应的活化能,结果表明pH值与温度对异丙酚的氧化动力学均有影响 相似文献
33.
陈建萍 《江苏大学学报(医学版)》1996,(3)
本文通过对38例危重新生儿血糖、胰岛素及皮质醇的研究,发现在危重新生儿组血糖与皮质醇的均植高于对照组(分别为P<0.05与P<0.01),且危重新生儿组高血糖的发生率(34.2%)也明显高于对照组(6%),而血胰岛素在各组之间无显著差异(P>0.05),研究表明危重新生儿易发生高血糖,其发生的机理与血皮质醇的升高及新生儿胰β细胞功能不良有关。 相似文献
34.
The greater potency of morphine-6-glucuronide (M6G) as well as the inactivity of morphine-3-glucuronide (M3G) with respect to the antinociceptive effects of the parent molecule, morphine (MOR), have been well established. It has been suggested that M3G is an antagonist of MOR's antinociceptive and respiratory depressive effects. The present study addressed the central nervous system (CNS) interaction of these opiate metabolites on their metabolic and hormonal effects. Whole body glucose kinetics were assessed on conscious, chronically catheterized, unrestrained rats. M3G (5 μg) or H2O (5 μl) was injected intracerebroventricularly (i.c.v.) 15 min prior to the bolus administration of H2O (5 μl), M6G (1 μg), or MOR (80 μg). i.c.v. M3G (5 μg) resulted in behavioral excitation, hyperglycemia (+50%), stimulation of glucose rate of appearance (Ra; +100%), glucose rate of disappeaance (Rd; +70%), and metabolic clearance rate (MCR; +33%) within 30 min after injection with no alterations in hormone concentrations. i.c.v. M6G and MOR produced progressive hyperglycemia with significantly high catecholamine and corticosterone levels. M3G pretreatment resulted in enhanced elevations in plasma glucose levels (+52% and +18%), plasma lactate (+138% and +108%), norepinephrine (+96% and +30%), and epinephrine (+62% and +67%) in response to both i.c.v. MOR and M6G administration. These findings suggest a non-opiate and non-hormonal mechanism for M3G-induced hyperglycemia. In contrast, the metabolic and hormonal responses to i.c.v. M6G and MOR are associated with elevations in catecholamine and corticosterone levels, which are remarkably enhanced by M3G pretreatment, most likely through accelerated catecholamine release. Our findings suggest a modulatory role for MOR glucuronidation, not only by rendering it inactive, as in the case of M3G, but by an interplay of the metabolic effects of the parent molecule and its metabolite 相似文献
35.
目的观察深圳宝安3~7岁健康幼儿血清糖、离子、非蛋白含氮类化合物表达水平。方法采用OLRPUSAU-640全自动生化仪及OLRPUS诊断试剂、东欧生物诊断试荆,检测316例体检健康幼儿血清中Ca^++、Mg^++、P^+++、GLU、BUN、Cr、UA的含量。结果①.1组与4组及2组与3、4组Ca^++组间方差分析,差异有统计学意义,P〈0.05。②.1组与2、3、4组Cr组间方差分析,差异有统计学意义P〈0.05。而Mg^++、P^+++、GLU、BUN、UA组间方差分析差异无统计学意义,P〉0.05。结论笔者证实了3~4岁健康幼儿与6~7岁健康幼儿及4~5岁健康幼儿与5~7岁健康幼儿血清Ca^++表达水平有差异。也证实了3~4岁健康幼儿与4~7健康幼儿Cr含量存在差异。由此可见,3~7岁健康幼儿建立自己的参考值是必要的。 相似文献
36.
P. M. Grasby T. Sharp T. Allen P. A. T. Kelly D. G. Grahame-Smith 《Psychopharmacology》1992,106(1):97-101
The azospirones gepirone (10 mg/kg), ipsapirone (10 mg/kg) and buspirone (10 mg/kg) were examined for their effect on regional cerebral glucose utilization in conscious rats using quantitative 2-deoxyglucose autoradiography. All three 5-HT1A partial agonists reduced glucose utilization in the hippocampus and dentate gyrus by 20–25% and increased glucose utilization by 38–65% in the lateral habenular nucleus; an important relay between striatal/limbic areas and the mid-brain raphe nuclei. The findings emphasize the potential importance of the hippocampus as a site of action for 5-HT1A receptor active drugs in vivo and also suggest that functional activity in the striatal/limbichabenular-raphe pathway may be influenced by gepirone, ipsapirone and buspirone. 相似文献
37.
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39.
KLEOMENIS BARLOS DIMITRIOS GATOS OLGA HATZI NICOLE KOCH SOFIA KOUTSOGIANNI 《Chemical biology & drug design》1996,47(3):148-153
S-4-methoxytrityl cysteine was synthesized and converted into the corresponding Fmoc-Cys(Mmt)-OH by its reaction with Fmoc-OSu. As compared to the corresponding Fmoc-Cys(Trt)-OH, the S-Mmt-function was found to be considerably more acid labile. Quantitative S-Mmt-removal occurs selectively in the presence of groups of the tert butyl type and S-Trt by treatment with 0.5–1.0% TFA. The new derivative was successfully utilized in the SPPS of Tyr1-somatostatin on 2-chlorotrityl resin. In this synthesis groups of the Trt-type were exclusively used for amino acid side-chain protection. Quantitative cleavage from the resin and complete deprotection was performed by treatment with 3% TFA in DCM–TES (95:5) for 30 min at RT. We observed no reduction of tryptophan under these conditions. © Munksgaard 1996. 相似文献
40.
Effect of Combined Norethisterone Enantate 50mg Monthly Injectable ContraceptiveonCarbohydrateMetabolismSunDan-li(孙丹利);ShengK... 相似文献